Patent Publication Number: US-2005124060-A1

Title: Enzyme activity measuring apparatus, enzyme activity measuring method, sample transcription apparatus and color measuring apparatus

Description:
CROSS REFERENCE TO RELATED APPLICATIONS  
      This application is based upon and claims the benefit of priority from the prior Japanese Patent Applications No. P2003-359911, filed on Oct. 20, 2003; the entire contents of which are incorporated herein by reference.  
     BACKGROUND OF THE INVENTION  
      1. Field of the Invention  
      The present invention relates to an enzyme activity measuring apparatus and an enzyme activity measuring method, a sample transcription apparatus and a color measuring apparatus used for measuring activity of enzyme. More particularly, the invention relates to an enzyme activity measuring apparatus and an enzyme activity measuring method, a sample transcription apparatus and a color measuring apparatus which measure activity of enzyme included in a sample by measuring color of on test paper which changes depending upon a transcribed sample.  
      2. Description of the Related Art  
      It is known that it is possible to determine a degree of stress of a subject person or whether the subject person has illness by measuring activity of amylase (a kind of enzyme) included in saliva.  
      Since amylase is included not only in saliva but also in a sample such as blood, it is possible to measure the degree of stress of a subject personal so by measuring activity of amylase included in blood. However, since it is usually painful to extract blood, it is not easy to extract blood as compared with saliva.  
      On the other hand, it is easy to extract saliva. However, the activity of amylase included in saliva is higher than activity of amylase included in blood. Therefore, if a reagent paper (reagent containing member) which measures the activity of amylase (amylase activity, hereinafter) is directly impregnated with saliva, the reaction of reagent included in the reagent paper immediately proceeds and completed. Thus, the reagent paper is also changed in color, and it becomes difficult to measure a difference of activity of amylase.  
      Thereupon, there is proposed a method for measuring the amylase activity included in saliva by holding a sample containing member such as nonwoven fabric impregnated with saliva (sample) and a reagent containing member such as a reagent paper using fingers. The saliva transcribed into the reagent containing member for predetermined time and depth of color (color depth) of the reagent containing member to which the saliva is transcribed is detected (for example, Japanese Patent Application Laid-open No. 2004-121214).  
     SUMMARY OF THE INVENTION  
      However, the discoloration of the reagent paper is largely varied depending upon the volume of amylase (saliva), i.e., the volume of saliva transcribed to the reagent paper including substrate that reacts with saliva, and time elapsed from the transcription. Especially, the color of the reagent paper is largely varied depending upon the difference of time elapsed from the transcription.  
      As described above, in the conventional technique, since the saliva is transcribed to the reagent paper by holding the reagent paper and the nonwoven fabric including saliva using user&#39;s fingers, there is a problem that the pushing force of the nonwoven fabric against the reagent paper is varied, and the volume of saliva transcribed to the test paper is not constant.  
      Further, in the conventional technique, after saliva is transcribed to the reagent paper, the reagent paper is inserted into the measuring apparatus and the color depth of the reagent paper is detected. However, there is a problem that time interval from the instant when the transcription of the saliva is started to the instant when the color of the reagent paper is measured is not constant.  
      That is, in the conventional technique, there is a problem that the amylase activity can not be measured precisely. This problem is also generated in enzyme other than amylase and in sample other than saliva.  
      The present invention has been accomplished in view of these problems, and it is an object of the present invention to provide an enzyme activity measuring apparatus, an enzyme activity measuring method, a sample transcription apparatus and a color measuring apparatus capable of more precisely measuring an activity of enzyme when the activity of enzyme is measured using an enzyme activity measuring reagent which measures activity of enzyme.  
      To solve the above problems, the present invention has the following features. According to a first aspect of the invention, an enzyme activity measuring apparatus (enzyme activity measuring apparatus  1  or enzyme activity measuring apparatus  200 ) comprises a reagent/sample disposing unit (reagent/sample disposing unit  5 ) configured to dispose a sample (for example, saliva) and a reagent containing member (reagent containing member  13 ) including an enzyme activity measuring reagent which measures an activity of an enzyme (for example, amylase) at a distance from each other, a sample transcription unit (sample transcription unit  7 , sample transcription unit  230 ) configured to bring the sample and the reagent containing member disposed by the reagent/sample disposing unit into contact with each other, and to transcribe a predetermined volume of the sample to the reagent containing member, a color depth measuring unit (color depth measuring unit  9 ) configured to measure a color depth of reagent included in the reagent containing member when predetermined time is elapsed after the sample is transcribed, and an enzyme activity detector (CPU  101 ) configured to detect the activity of enzyme included in the sample based on the color depth measured by the color depth measuring unit.  
      According to a second aspect of the invention, in the first feature, the reagent containing member is a sheet member, the sample is included in a sample containing member (saliva extracting sheet  15 ) which is a sheet member, the reagent/sample disposing unit disposes a reagent containing member flat surface (flat surface portion  13 A) which is a flat surface portion of the reagent containing member and a sample containing member flat surface (flat surface portion  15 A) which is a flat surface portion of the sample containing member such that these flat surfaces are opposed to each other in substantially parallel to each other, the sample transcription unit brings the reagent containing member flat surface and the sample containing member flat surface into contact with each other for predetermined time under predetermined pressure.  
      According to a third aspect of the invention, in the second feature, the reagent/sample disposing unit disposes the reagent containing member and the sample containing member at a distance from each other using a holder (holder  17 ) which holds the reagent containing member and the sample containing member, the sample transcription unit pushes the holder to bring the reagent containing member flat surface and the sample containing member flat surface into contact with each other.  
      According to a fourth aspect of the invention, in the third feature, the enzyme activity measuring apparatus further comprises a cover (cover  3 , cover  210 ) which covers the color depth measuring unit and which opens and closes around a turning shaft (hinge  3 G, hinge  215 ), the sample transcription unit is provided on the cover.  
      According to a fifth aspect of the invention, in the fourth feature, the enzyme activity measuring apparatus further comprises a projecting member (hook  257 ) which moves in a direction substantially perpendicular to a pushing direction in which the sample transcription unit pushes the holder, the cover is provided with an insertion hole (insertion hole  210   a ) into which the projecting member is inserted in a state in which the cover is closed.  
      According to a sixth aspect of the invention, in the fifth feature, the projecting member is biased in an insertion direction into the insertion hole, the enzyme activity measuring apparatus further comprises a projecting member moving lever (lever  253 ) which is engaged with the projecting member and which moves the projecting member in a direction opposite from the insertion direction by turning the projecting member moving lever around the turning shaft (turning shaft  254 ), and a cover opening button portion (cover opening button  250  and push rod  252 ) which pushes the projecting member moving lever and which turns the projecting member moving lever when the cover opening button portion is pushed down.  
      According to a seventh aspect of the invention, in the fourth feature, the sample transcription unit comprises a movable member (movable member  237 ) which has a pushing surface (pushing surface  237   pp ) for pushing the holder and a cam abutment surface (cam abutment surface  237   cp ) which is opposed to the pushing surface, and which can move around the pushing direction in which the holder is pushed, a cam having a flat surface portion (flat surface portion  231   p ) on a portion of its outer peripheral surface in which a distance from the turning shaft (turning shaft  234 ) to the outer peripheral surface is longer than that of other portion, a transcription lever (transcription lever  232 ) which brings the flat surface portion into abutment against the cam abutment surface by turning the transcription lever into a first direction, a first biasing member (coil spring  233 ) configured to bias the cam such as to turn the cam in a second direction which is opposite from the first direction, and a second biasing member (coil spring  239 ) configured to bias the movable member toward the cam.  
      According to an eighth aspect of the invention, in the seventh feature, the enzyme activity measuring apparatus further comprises a third biasing member (coil spring  235 ) configured to bias the transcription lever such as to turn the transcription lever in the second direction.  
      According to a ninth aspect of the invention, in the first feature, the enzyme activity measuring apparatus further comprises a temperature detector (photodiode  26  and temperature detector  129 ) configured to detect a sample temperature which is a temperature of the sample, a sample temperature correcting data storing unit (storing unit  109 ) configured to store sample temperature correcting data in which the sample temperature and correcting rate for correcting the activity detected by the enzyme activity detector are associated with each other, and an activity correcting unit (CPU  101 ) configured to correct the activity based on the sample temperature and the sample temperature correcting data.  
      According to a tenth aspect of the invention, in the ninth feature, the enzyme activity measuring apparatus further comprises a heater (heater  260 ) configured to heat the sample to predetermined temperature, and a heater controller (CPU  101 ) configured to stop the operation of the heater when the temperature detector detects that the sample temperature reaches the predetermined temperature.  
      According to an eleventh aspect of the invention, in the first feature, the color depth measuring unit irradiates the reagent containing member flat surface with light substantially at right angles, the color depth is measured by measuring reflected intensity of light from the reagent containing member flat surface from a direction which is diagonal with respect to the reagent containing member flat surface.  
      According to a twelfth aspect of the invention, in the eleventh feature, the color depth measuring unit measures the reflected intensity of light by receiving the same through optical fiber (optical fiber  25 ).  
      According to a thirteenth aspect, in the first feature, the enzyme is amylase, and the sample is saliva.  
      According to a fourteenth aspect of the invention, an enzyme activity measuring method comprises a reagent/sample disposing step for disposing a sample and a reagent containing member including an enzyme activity measuring reagent which measures an activity of an enzyme at a distance from each other, a sample transcription step for bringing the sample and the reagent containing member disposed by the reagent/sample disposing unit into contact with each other, and for transcribing a predetermined volume of the sample to the reagent containing member, a color depth measuring step for measuring depth of color of reagent included in the reagent containing member when predetermined time is elapsed after the sample is transcribed, and an enzyme activity detecting step for detecting the activity of enzyme included in the sample based on the color depth measured by the color depth measuring unit, and in the reagent/sample disposing step, a reagent containing member flat surface which is a flat surface portion of the reagent containing member and a sample containing member flat surface which is a flat surface portion of the sample containing member are disposed such that these flat surfaces are opposed to each other in substantially parallel to each other, and in the sample transcription step, the reagent containing member flat surface and the sample containing member flat surface are brought into contact with each other for predetermined time under predetermined pressure.  
      According to a fifteenth aspect of the invention, a sample transcription apparatus comprises a reagent/sample disposing unit configured to dispose a sheet reagent containing member including enzyme activity measuring reagent which measures activity of enzyme and a sheet sample containing member including sample at a distance from each other, and a sample transcription unit which bring the reagent containing member and the sample disposed by the reagent/sample disposing unit and which transcribes a predetermined volume of sample to the reagent containing member, and the reagent/sample disposing unit disposes a reagent containing member flat surface which is a flat surface portion of the reagent containing member and a sample containing member flat surface which is a flat surface portion of the sample containing member such that these flat surfaces are opposed to each other in substantially parallel to each other, and the sample transcription unit brings the reagent containing member flat surface and the sample containing member flat surface into contact with each other for predetermined time under predetermined pressure.  
      According to a sixteenth aspect of the invention, a color measuring apparatus comprises a color depth measuring unit which irradiates a reagent containing member flat surface which is a flat surface portion of a sheet reagent containing member including an enzyme activity measuring reagent which measures activity of enzyme with light substantially at right angles, and which measures the light reflected from the reagent containing member flat surface from a direction which is diagonal with respect to the reagent containing member flat surface, thereby measuring the depth of color of the reagent containing member.  
      According to a seventeenth aspect of the invention, in the sixteenth feature, the color depth measuring unit measures the reflected intensity of light by receiving the same through optical fiber.  
      According to these aspects of the present invention, it is possible to provide an enzyme activity measuring apparatus, an enzyme activity measuring method, a sample transcription apparatus and a color measuring apparatus capable of more precisely measuring an activity of enzyme when the activity of enzyme is measured using an enzyme activity measuring reagent which measures activity of enzyme. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       FIG. 1  is a perspective view showing an outline structure of an enzyme activity measuring apparatus according to a first embodiment of the present invention;  
       FIG. 2  is a perspective view of the enzyme activity measuring apparatus as viewed from the direction F 2  shown in  FIG. 1 ;  
       FIG. 3  is a sectional view taken along the direction F 3 -F 3  shown in  FIG. 2 ;  
       FIG. 4  is a sectional view taken along the direction F 4  shown in  FIG. 3 ;  
       FIG. 5  is a schematic sectional view of a color depth measuring unit of the enzyme activity measuring apparatus according to the first embodiment of the invention;  
       FIG. 6  is a graph showing the relation between a reaction degree of enzyme and elapsed time when a substrate and an amylase come into contact with each other;  
       FIG. 7  is a graph showing the relation between output voltage which is converted based on reflection light and elapsed time;  
       FIG. 8  is a graph showing the relation between color depth of a substrate and elapsed time when a substrate and an amylase come into contact with each other;  
       FIG. 9  is a block diagram of a CPU substrate provided in the enzyme activity measuring apparatus of the embodiment of the invention;  
       FIG. 10  is a block diagram of a sensor substrate provided in the enzyme activity measuring apparatus of the embodiment of the invention;  
       FIG. 11  is a flowchart showing the operation for measuring an amylase activity using the enzyme activity measuring apparatus;  
       FIG. 12  is a flowchart showing the operation for measuring the amylase activity using the enzyme activity measuring apparatus;  
       FIG. 13  is a flowchart showing the operation for measuring the amylase activity using the enzyme activity measuring apparatus;  
       FIG. 14  is a perspective view of an enzyme activity measuring apparatus according to a second embodiment of the invention;  
       FIG. 15  is a plan view of the enzyme activity measuring apparatus of the second embodiment of the invention;  
       FIG. 16  is a plan view (cover is opened) of the enzyme activity measuring apparatus of the second embodiment of the invention;  
       FIG. 17  is a sectional view taken along the direction F 17 -F 17  shown in  FIG. 15 ;  
       FIG. 18  is an explanatory view for explaining the operation of a cover opening/closing mechanism provided in the enzyme activity measuring apparatus of the second embodiment of the invention;  
       FIG. 19  is a side view of a sample transcription unit as viewed from the direction F 19  shown in  FIG. 15 ;  
       FIG. 20  is an explanatory view for explaining the operation of the sample transcription unit provided in the enzyme activity measuring apparatus according to the second embodiment of the invention;  
       FIG. 21  is a schematic block diagram of a color depth measuring unit provided in the enzyme activity measuring apparatus according to the second embodiment of the invention;  
       FIG. 22A  is a graph showing the relation (temperature characteristics) between a sample temperature and an activity rate of amylase included in the sample;  
       FIG. 22B  is a graph showing a correcting curve of the sample temperature determined based on the temperature characteristics;  
       FIG. 23  is a flowchart showing a portion of operation carried out in the enzyme activity measuring apparatus according to the second embodiment of the invention; and  
       FIG. 24  is a schematic block diagram of a base and a heater according to the second embodiment of the invention.  
    
    
     DESCRIPTION OF THE PREFFERED EMBODIMENTS  
     First Embodiment  
      A first embodiment of an enzyme activity measuring apparatus according to the present invention will be explained.  FIG. 1  is a schematic perspective view of a structure of the enzyme activity measuring apparatus  1  of the first embodiment of the invention.  FIG. 2  is a perspective view of the enzyme activity measuring apparatus  1  as viewed from a direction F 2  shown in  FIG. 1 .  
      In  FIG. 1 , a cover  3  is opened. In  FIG. 2 , the cover  3  is closed.  
      The enzyme activity measuring apparatus  1  measures activity using an enzyme activity measuring reagent. The following explanation, saliva (human&#39;s saliva) is used as an example of a sample and amylase is used as an example of enzyme, but the present invention is not limited to saliva and amylase.  
      The enzyme activity measuring apparatus  1  includes a reagent/sample disposing unit  5 . The reagent/sample disposing unit  5  disposes a reagent containing member  13  including an amylase activity measuring reagent which is one of enzyme activity measuring reagents and a saliva extracting sheet  15  including saliva at a distance from each other.  
      The enzyme activity measuring apparatus  1  includes a sample transcription unit  7 . The sample transcription unit  7  brings the disposed reagent containing member  13  and saliva (saliva extracting sheet  15 ) into contact with each other to transcribe a predetermined volume of saliva to the reagent containing member  13 .  
      The enzyme activity measuring apparatus  1  also includes a color depth measuring unit  9  which measures depth of color of the reagent included in the reagent containing member  13  when predetermined time is elapsed after the saliva is transcribed. The activity of the detected amylase is displayed on a LCD panel  117 A (see  FIG. 2 ).  
      Here, amylase will be explained. As a typical amylase, there is α-amylase is secreted from human&#39;s salivary gland or pancreatic gland. The amylase is digestive enzyme having molecular weight of 54,000 to 62,000 which is hydrolytic degradation polysaccharide such as starch and amylase.  
      It is known that the amylase activity in saliva is largely varied depending upon physical condition or individuals. A normal activity is about tens of thousands, but the activity may exceed hundreds of thousands depending upon physical condition or physical predisposition, or even in a healthy person in some cases.  
      As the substrate of the reagent for measuring the amylase activity used in this embodiment, modified oligosaccharide is used. The term “modified” means that a compound for labeling is bound to an end, reducing end of oligosaccharide, and the end can be liberated by amylase or conjugated enzyme. The number of sugar of the modified oligosaccharide is in a range of G2 to G7, and preferably in a range of G2 to G5.  
      As the compound for labeling, chromogenic compound can generally be used. As preferable groups are 4-nitrophenyl (PNP), 2-chloro-4-nitrophenyl (CNP) and 2,4-dichlorophenyl (Cl2P).  
      Concrete examples of modified oligosaccharide which is modified with chromagenic are 2-chloro-4-nitrophenyl-4-O-β-D-Galacto pyranose sylmalto side (GAL-G2-CNP, hereinafter), GAL-G-4-CNP, GAL-G5-CNP, G5-CNP(2-chloro-4-nitrophenyl maltopentaose), G7-CNP, G5-PNP(p-nitrophenyl maltopentaose), G6-CNP(2-chloro-p-nitrophenyl maltotetraose) and G7-PNP.  
      Among these modified oligosaccharide, preferable examples are GAL2-G2-CNP and GAL-G4-CNP in which the number of cut portions generated when hydrolysis is carried out by amylase is limited to one. Such modified oligosaccharide can be expressed using general formula as shown below.  
                 
 
      In the formula, R1 and R2 means hydrogen atoms or protective groups. The protective group is not especially limited, but examples thereof are non-substituted or substituted low grade alkyl, low grade alkoxyl or phenyl, azido group, halide atom, N-monoalkyl monoalkyl carbamoyl oxy group, alkyl or aryl sulfonyl oxy group or alkyl oxy group, α-glucosyl, α-maltosyl and β-galaxytol. Further, R1 and R2 may be cross linked with each other, or the cross-link group may further have substituent.  
      In the formula, R3 means a signal generating group, for example, group capable of optically detecting a signal (preferably, color forming aromatic group), and n is in a range of 0 to 5. In the above formula, —OR3 means that β- is bound to a portion of a reducing end glucose, but α- may be bound to the portion.  
      In the amylase activity measuring reagent (reagent containing member  13 ) of this embodiment, a substrate is carried on a support body (reagent paper such as filter paper).  
      Here, the expression “carried on support body” means that substrate and competitive enzyme inhibiting agent are fixed to or trapped in water-insoluble organic or inorganic carrier. It is preferable that the support body is in a form of a thin film, and a thickness of the support body is in a range of 100 μm to 500 μm, preferably in a range of 150 μm to 400 μm.  
      It is preferable that the thin film is white in color. Preferable materials of the thin film are nitrocellulose, porous glass or paper, but the material is not limited to them, and any material may be used only if it can efficiently carry the substrate. In this embodiment, even if a reagent is carried on a support body other than paper (such as nitrocellulose), it is called “reagent paper” but “reagent paper” also includes other material other than paper.  
      It is preferable that the amount of modified oligosaccharide carried on the support body is adjusted to a constant value. As a simple method, there is a method in which support body is immerse into solution including 2 to 500 mmol/L of modified oligosaccharide substrate for about 1 to 5 minutes, and the support body is dried.  
      In measurement of amylase activity in this embodiment, the amylase activity is determined based on change in absorbance by means of disengagement of chromagenic such as CNP and PNP which are modified materials of substrate or by color forming of reagent support body. For example, CNP is measured by absorbance of 405 nm.  
      Usually, the chromogenic can be liberated only by action of largely excessive amylase. If necessary, there is used a conjugated enzyme method including reaction for liberating the chromagenic by amylase, α-glucosidase, β-glucosidase and the like after hydrolytic reaction of amylase. In this case, it is necessary to introduce means for adding the additional enzyme as a reagent. To facilitate the reaction, known activator of α-amylase may be used.  
      The reaction temperature in this measurement is not especially limited, but preferable temperature is in a range of 25 to 40° C. The reaction time is 1 to 10 minutes, but the time is varied depends on kinds of substrate and conjugated enzyme.  
      To measure the change caused by color forming, later-described LED  21 , photodiode  23  and the like are used. The change of absorbance caused by color forming of support body can be measured by reflected intensity of light or trans illumination.  
      As a light source for measurement, it is possible to use laser, a halogen lamp, tungsten lamp and the like in addition to the light-emitting diode (LED  21  shown in  FIG. 5 ). The light source is not limited to them.  
      The reagent containing member  13  is a sheet member. The saliva extracting sheet  15  is also made of sheet member (for example, nonwoven fabric).  
      The reagent/sample disposing unit  5  disposes a flat surface portion  13 A (reagent containing member flat surface) which is a flat surface portion of the reagent containing member  13  and a flat surface portion  15 A (sample containing member flat surface) which is a flat surface portion of the saliva extracting sheet  15  including saliva such that both the flat surface portions are opposed to each other substantially in parallel to each other.  
      The reagent/sample disposing unit  5  disposes the reagent containing member  13  and the saliva extracting sheet  15  including sample using a holder  17 . The holder  17  holds the reagent containing member  13  and the saliva extracting sheet  15  including sample (saliva).  
      The sample transcription unit  7  brings the flat surface portion  13 A of the reagent containing member  13  and the flat surface portion  15 A of the saliva extracting sheet  15  into contact with each other for predetermined time under predetermined pressure.  
      Specifically, the sample transcription unit  7  pushes the holder  17  by means of a later-described cam  41 , and brings the flat surface portion  13 A and the flat surface portion  15 A into contact with each other. More specifically, the sample transcription unit  7  deforms the reagent holding portion  17 A which holds the reagent containing member  13  and a portion in the vicinity of the reagent holding portion  17 A by predetermined amount, and brings the flat surface portion  13 A and the flat surface portion  15 A into contact with each other.  
      Instead of the reagent holding portion  17 A which holds the reagent containing member  13  and the portion in the vicinity of the reagent holding portion  17 A, a portion where the saliva extracting sheet  15  is held and a portion in the vicinity of this portion may be deformed. That is, at least one of the reagent holding portion  17 A where the reagent containing member  13  is held and a portion (including a portion in the vicinity thereof) where the saliva extracting sheet  15  is held may be deformed by a predetermined amount, and the flat surface portion  13 A and the flat surface portion  15 A may be brought into contact with each other.  
      As described above, the color depth measuring unit  9  measures the depth of color of reagent included in the reagent containing member  13 .  
      More specifically, as shown in  FIG. 5 , the color depth measuring unit  9  irradiates the flat surface portion  13 A with light substantially at right angles by means of the LED  21 , the color depth measuring unit  9  measures the light reflected from the flat surface portion  13 A from a direction diagonal with respect to the flat surface portion  13 A using the photodiode  23  (PD  23 , hereinafter), thereby measuring the depth of color of the reagent containing member  13  (flat surface portion  13 A).  
      The PD  23  receives reflection light from the flat surface portion  13 A through an optical fiber  25 . The enzyme activity measuring apparatus  1  includes a cover  3  which restrains disturbance light from entering into the color depth measuring unit  9 . If the cover  3  is closed, the holder  17  is fixed to a base  29 .  
      The sample transcription unit  7  is provided on the cover  3 . If the cover  3  is closed, a reagent holding portion  17 A of the holder  17  is deformed so that the flat surface portion  13 A and the flat surface portion  15 A can be brought into contact with each other.  
      The reagent/sample disposing unit  5  and the sample transcription unit  7  will be explained in detail.  FIG. 3  is a sectional view taken along the direction F 3 -F 3  shown in  FIG. 2 . In  FIG. 3 , the reagent containing member  13  and the saliva extracting sheet  15  are disposed by the reagent/sample disposing unit  5 .  FIG. 3  shows that the reagent containing member  13  and the saliva extracting sheet  15  are in contact with each other by means of the sample transcription unit  7 .  
       FIG. 4  is a sectional view taken along the direction F 4  shown in  FIG. 3 .  FIG. 4  shows a portion of each of the reagent containing member  13 , the reagent holding portion  17 A holding the reagent containing member  13 , the saliva extracting sheet  15  and the sample transcription unit  7  so that the invention can be understood easily. The reagent holding portion  17 A is provided on the side of the inner surface side of the holder  17 .  
      As shown in  FIG. 1 , the saliva extracting sheet  15  is provided on one surface of one end of a long plate-like base material  27  (for example, white synthetic resin). The holder  17  is of rectangular solid shape, and the base material  27  can be inserted into the holder  17 .  
      The reagent holding portion  17 A where the reagent containing member  13  is held is located on the upper surface of the holder  17 . The reagent holding portion  17 A functions as a leaf spring by a notch  17 B extending substantially in parallel to a longitudinal direction of the holder  17 .  
      As shown in  FIG. 4 , arc portions  17 C is formed at opposite ends in longitudinal direction of the reagent holding portion  17 A so that the reagent holding portion  17 A can easily be bent.  
      If the base material  27  provided with the saliva extracting sheet  15  is inserted into the holder  17  from the direction of AR 1  (see  FIG. 1 ) and the holder  17  is set to the base  29  such that the saliva extracting sheet  15  is located at the position P shown with broken line, the reagent containing member  13  (flat surface portion  13 A) and the saliva extracting sheet  15  (flat surface portion  15 A) are disposed at a distance from each other.  
      The base  29  is provided on the upper surface of the enzyme activity measuring apparatus  1 , extends in the longitudinal direction of the enzyme activity measuring apparatus  1  and has a groove shape. A casing  1 A of the enzyme activity measuring apparatus  1  including the base  29  is made of black synthetic resin.  
      When the holder  17  is set on the base  29 , a bottom surface  17 D of the holder  17  opposed to the reagent holding portion  17 A and a bottom surface  29 A of the base  29  come into contact with each other in a surface-to-surface manner. Further, an end surface  17 E of the holder  17  and an end surface  29 B of the base  29  come into contact with each other in a surface-to-surface manner, and a side surface  17 F of the holder  17  and a side surface  29 C of the base  29  come into contact with each other in a surface-to-surface manner.  
      A projection  17 G provided on the side surface of the holder  17  and a notch  29 D provided in the side surface  29 C of the base  29  come into contact with each other. Since the holder  17  is set on the base  29  in this manner, the holder  17  can move only in a direction other than upper direction of the enzyme activity measuring apparatus  1 .  
      Since an upper surface, a lower surface and side surfaces of the holder  17  have different shapes, it is possible to easily and precisely set the holder  17  on the base  29 . Further, the holder  17  can be set on the base  29  only in the correct direction, and operation mistake of a user can be prevented.  
      Next, the sample transcription unit  7  will be explained. As shown in  FIG. 3 , the sample transcription unit  7  includes a plate-like movable portion  33 . The movable portion  33  engages with a columnar guide portion  31  which vertically stands on the inner surface  3 A of the box-like cover  3 . The movable portion  33  moves toward and away from the inner surface  3 A. Flat surface portions  33 A and  33 B and an inner surface  3 A of the inner surface  3 A are substantially in parallel to one another. In this embodiment, the cover  3  and the movable portion  33  are made of black synthetic resin.  
      The inner surface  3 A is provided with a columnar guide portion  35  which vertically stands on the inner surface  3 A. The guide portion  35  is provided at its tip end  35 A with a spring holding portion  37  having an outer diameter greater than that of the guide portion  35 .  
      A coil spring  39  is provided between the spring holding portion  37  and the movable portion  33 . That is, the movable portion  33  is biased toward the inner surface  3 A by the coil spring  39 .  
      A cam  41  abuts against the flat surface portion  33 B (inner surface  3 A), and the movable portion  33  moves in response to the turning motion of the cam  41 . The cam  41  can turn around a turning shaft  41   r , and one end of the cam  41  is provided with a transcription lever  41 A through which a user can turn the cam  41 .  
       FIGS. 3 and 4  show the reagent containing member  13  and the saliva extracting sheet  15  which are in contact with each other. In  FIG. 4 , as shown with phantom lines (a state as shown with phantom lines in  FIG. 2  and to a state shown with solid line in  FIG. 2 ), if the cam  41  is turned, the movable portion  33  moves in the direction of AR 3  (see  FIG. 3 ), i.e., toward the inner surface  3 A by the coil spring  39 , and the reagent containing member  13  and the saliva extracting sheet  15  are separated from each other.  
      The cam  41  is manually operated by the user of the enzyme activity measuring apparatus  1 . Instead of the cam  41 , a solenoid which pushes the holder  17  may be operated under control of a later-described CPU  101 . In a state in which the reagent containing member  13  and the saliva extracting sheet  15  are in contact with each other by the cam  41 , the position of the cam  41  is held, and the cam  41  is not turned unintentionally.  
      The flat surface portion  33 A of the movable portion  33  is provided with a rectangular solid transcription pad  43  (pushing member) which pushes the reagent holding portion  17 A. The transcription pad  43  is made of hard member such as metal.  
      The cover  3  turns around a hinge  3 G (turning shaft, see  FIG. 1 ). As shown in  FIG. 2 , the cover  3  can be closed by turning the cover  3  around the hinge  3 G. If the cover  3  is closed, the cover  3  can be fixed using a hook  45  so that the cover  3  is not opened.  
      If the transcription lever  41 A is turned to move the movable portion  33  toward the holder  17 , the reagent holding portion  17 A is pushed by the transcription pad  43  and deformed, and the reagent containing member  13  and the saliva extracting sheet  15  are brought into contact with each other under predetermined pressure.  
      As shown in  FIG. 1 , the inner surface  3 A is provided with a rib  3 B. If the cover  3  is closed, an end surface  3 C of the rib  3 B comes into contact with an upper portion  17 H of the holder  17  and slightly biases the upper portion  17 H. Thus, the holder  17  is fixed such that the holder  17  can not move upward.  
      The inner surface  3 A is provided with a projection  3 D. If the cover  3  is closed, the projection  3 D is inserted into a hole  1 B formed in the casing  1 A.  
      The projection  3 D inserted into the hole  1 B operates a limit switch (not shown) provided in the casing  1 A, and the closed state of the cover  3  is detected.  
      As described above, if the cover  3  is closed, light toward the base  29  is blocked. If the cover  3  is closed, an end surface  3 E around the opening of the cover  3  and a flat surface portion  1 C around the base  29  come into contact with each other. A bottom surface  29 A (concretely, upper surface  47 A of the substrate  47  provided with the PD  23 , see  FIG. 5 ) is located higher than the position of the contacted portion in the vertical direction.  
      This is because that adverse influence on the measurement using the disturbance light is prevented. That is, the disturbance light (sunlight or electric light) pours from downward from above. Thus, as described above, if the bottom surface  29 A is disposed higher than the contacted portion, the adverse influence on the measurement using the disturbance light can be prevented.  
      The movable portion  33  is provided with a projection  33 C. If the cover  3  is closed, the projection  33 C is inserted into a hole  1 D formed in the casing  1 A.  
      If the movable portion  33  is moved into a state in which the movable portion  33  pushes the holder  17  (states shown in  FIGS. 3 and 4 ), a limit switch (not shown) provided in the casing  1 A is operated, and the transcription of the saliva to the reagent containing member  13  is detected.  
      According to the sample transcription unit  7 , since the movable portion  33  and the transcription pad  43  move in parallel to each other, uniform load can be applied to the holder  17 . Thus, uniform transcription of saliva can be realized. Since the transcription lever  41 A is used, it is possible to prevent excessive load from being applied to the holder  17 .  
      Since the cover  3  is provided with the sample transcription unit  7 , the enzyme activity measuring apparatus  1  can be reduced in size. A darkroom can easily be formed by the cover  3 , and the disturbance light which causes an adverse influence on the measurement can effectively blocked.  
      When change of color of the reagent containing member  13  is to be measured, it is necessary to precisely manage the time during which the reagent containing member  13  and the saliva extracting sheet  15  are brought into contact with each other. According to the sample transcription unit  7 , since the limit switch which is operated in accordance with operation of the movable portion  33  is provided, the time during which the reagent containing member  13  and the saliva extracting sheet  15  are brought into contact with each other, i.e., the transcription time of saliva can precisely detected.  
      Since the transcription pad  43  is made of hard member such as metal, it is possible to prevent the transcription pad  43  from being worn. Since the transcription pad  43  is made of different member from that of the movable portion  33 , various specification changes such as shape, material and hardness of the transcription pad  43  can easily be accepted.  
      Since the saliva can be transcribed only by turning the transcription lever  41 A, the saliva can easily and reliably be transcribed as compared with the conventional technique.  
      Next, the color depth measuring unit  9  will be explained in detail.  FIG. 5  is a schematic sectional view of the color depth measuring unit  9 .  
      As described above, the color depth measuring unit  9  measures the depth of color of the flat surface portion  13 A of the reagent containing member  13 .  
      The color depth measuring unit  9  measures the depth of color of the reagent containing member  13  (flat surface portion  13 A) when predetermined time is elapsed after the sample transcription unit  7  starts transcription of the saliva.  
      When the depth of color is to be measured by the color depth measuring unit  9 , the base material  27  is removed from the holder  17 . That is, nothing is interposed between the LED  21  (optical fiber  25 ) and the reagent containing member  13  (flat surface portion  13 A). Also, nothing is interposed between the PD  23  and the reagent containing member  13  (flat surface portion  13 A). As shown in  FIG. 2 , even if the cover  3  is closed, the base material  27  can be removed through a notch portion  3 F provided in the cover  3 .  
      The LED  21 , the PD  23  and the optical fiber  25  are provided on the substrate  47  made of black synthetic resin. The upper surface  47 A of the substrate  47  is located substantially at the same height as the bottom surface  29 A of the base  29 . The upper surface  47 A and the flat surface portion  13 A are disposed substantially in parallel to each other.  
      A straight line CL 1  connecting the LED  21  and a center of the flat surface portion  13 A forms a right angle with respect to the flat surface portion  13 A. A straight line CL 3  connecting the PD  23  and the center of the flat surface portion  13 A is inclined with respect to the flat surface portion  13 A.  
      When light reflected from the flat surface portion  13 A is measured by the PD  23 , an angle formed between the flat surface portion  13 A and a color forming portion (flat surface portion  13 A) of the reagent containing member  13  (test paper) is 0 to 50°, preferably 10 to 45°, and more preferably 10 to 30°.  
      A distance between the flat surface portion  13 A and the PD  23  is 10 to 30 mm, preferably 15 to 25 mm, and more preferably 18 to 22 mm. A spot diameter of reagent (diameter of portion irradiated with light) is 1 to 5 mm, preferably 2 to 4 mm, and more preferably 2.5 to 3.5 mm.  
      Although the depth of color of the reagent containing member  13  is measured in the color depth measuring unit  9 , if a degree of reaction of reagent included in the reagent containing member  13  (color depth of reagent) can be detected, another method may be used.  
      Next, decomposition of substrate of reagent by amylase will be explained.  FIG. 6  is a graph showing the relation between the enzyme reaction degree and elapsed time when the substrate and amylase come into contact with each other. Here, graph G 1  shown in  FIG. 6  shows a case in which the activity of amylase is low, graph G 3  shows a case in which the activity of amylase is intermediate degree, and graph G 5  shows a case in which the activity of amylase is high.  
      As shown in  FIG. 6 , as the activity of amylase is higher, the enzyme reaction proceeds faster. The enzyme reaction is carried out until the substrate is decomposed and disappears. As the enzyme reaction proceeds, the reagent containing member  13  colors such that yellow is deep.  
       FIG. 7  is a graph showing the relation between elapsed time and output voltage converted based on the reflection light detected by the PD  23 . In  FIG. 7 , the graph G 7  shows a case in which the activity of amylase is low, graph G 9  shows a case in which the activity of amylase is intermediate degree, and graph G 11  shows a case in which the activity of amylase is high.  
       FIG. 8  is a graph showing the relation between the elapsed time and density of substrate when the substrate and amylase come into contact with each other. In  FIG. 8 , the graph G 13  shows a case in which the activity of amylase is low, graph G 15  shows a case in which the activity of amylase is intermediate degree, and graph G 17  shows a case in which the activity of amylase is high.  
      As shown in  FIG. 8 , as the activity of amylase is higher, reaction of more enzymes occurs in short time, and the density of substrate is lowered.  
      As described above, the enzyme reaction (decomposition reaction of substrate by amylase) is started from the instant when the saliva extracting sheet  15  including saliva and the reagent containing member  13  (test paper) come into contact with each other. Also while the saliva is immersed from the saliva extracting sheet  15  into the entire reagent containing member  13  (test paper), the reaction proceeds at the contact surface portion. The instant when the enzyme reaction is started is a reference for measuring the depth of color of the reagent containing member  13 . Thus, it is possible to precisely detect this instant as described above.  
      The time required for transcribing the saliva may be time during which saliva can be impregnated into the entire reagent containing member  13  (test paper). However, if the transcription is continued more than necessary, the melted substrate is reversely transcribed to the saliva extracting sheet  15  and this causes error in measurement. Thus, it is preferable complete the transcription at appropriate time.  
      The transcription of saliva is completed by turning the transcription lever  41 A from the position shown with phantom line to the position shown with solid line (see  FIG. 2 ). In other words, the transcription of the saliva is completed by a simple operation, i.e., by returning the transcription lever  41 A.  
      By returning the transcription lever  41 A, the flat surface portion  13 A and the flat surface portion  15 A are separated from each other, and the transcription of the saliva is completed.  
      A user manually returns the transcription lever  41 A, but the user is informed of the returning timing of the transcription lever  41 A by allowing a buzzer on the enzyme activity measuring apparatus  1  to sound. The timing of allowing the buzzer to sound is set to the instant when predetermined time (for example, 10 seconds) is elapsed after the limit switch is operated by the projection  33 C.  
      If the transcription of saliva is completed, the user removes the base material  27  from the enzyme activity measuring apparatus  1 , and measurement by the color depth measuring unit  9  is carried out without delay.  
      It is necessary to measure the amylase activity before the reaction of enzyme is completed as described above. The measurement value is varied depending upon time elapsed after the enzyme reaction is started. Thus, time elapsed after the transcription of saliva is started is measured by a real time clock IC (CPU  101  shown in  FIG. 9 ), and if the preset time is elapsed, the measurement is carried out automatically.  
      According to the enzyme activity measuring apparatus  1  of this embodiment explained above, the following working effect can be obtained.  
      The transcription operation and the transcription-releasing operation which do not require high precision are carried out manually. Thus, the number of parts of the sample transcription unit  7  can be reduced, and its structure can be simplified.  
      Since the CPU  101  measures the transcription time of saliva, it is possible to precisely manage the time elapsed after the trnasfer of saliva is started. When the predetermined time is elapsed, since the buzzer sounds, it is possible to prevent the transcription of saliva from being continued more than necessary.  
      Next, color forming of reagent included in the reagent containing member  13  will be explained in detail. The color forming of reagent means incensement of depth of color forming material, but it is difficult to quantitatively grasp the degree of color forming by the unaided eye.  
      Thereupon, the color forming degree is grasped quantitatively, the LED  21  irradiates the reagent containing member  13  (test paper) with light having wavelength in accordance with the wavelength of formed color, and the luminance of reflection light or scattered light of the irradiated light is measured by the PD  23 .  
      As described above, all of the LED  21 , PD  23  and optical fiber  25  are mounted on the substrate  47 . In this embodiment, a diode having a peak wavelength of 430 nm is used as the LED  21 , and a photodiode having sensitivity at wavelength of 430 to 450 nm is used as the PD  23 .  
      A single core type sensor optical fiber is used as the optical fiber  25 . The bottom surface  29 A of the base  29  and the substrate  47  are colored with matte black.  
      Light irradiated from the LED  21  is reduced in diameter to a predetermined spot diameter by a diaphragm (not shown), and the diameter-reduced light is emitted to the reagent containing member  13  (flat surface portion  13 A). The emitted light passes through, is scattered or is reflected, and a portion of the light reaches the PD  23  through the optical fiber  25 . The PD  23  outputs voltage in accordance with the illumination of the light which reached through the optical fiber  25  (concretely, voltage value converted based on current value which is output from the PD  23 ) as shown in  FIG. 7 .  
      Since the bottom surface  29 A and the substrate  47  are colored with matte black, light leaked from the LED  21  or entering light is prevented from being reflected irregularly. By setting the spot diameter to the size of the reagent containing member  13  (flat surface portion  13 A), it is possible to prevent the light from being emitted to the direction other than the flat surface portion  13 A, and to reduce the irregular reflection which may cause error.  
      It is possible to uniformly irradiate the flat surface portion  13 A with light by throwing the light emitted from the LED  21  out of focus, and it is possible to stably measure the color depth of the flat surface portion  13 A (reagent).  
      The absorbance of the color forming reagent is varied most remarkably in the wavelength band region of 420 to 450 nm. Thus, if LED  21  suitable of this wavelength is used, it is possible to detect the color depth of reagent which emits color with excellent sensitivity.  
      By using the PD  23  having sensitivity at 430 to 450 nm, it is possible to reduce the influence on excessive disturbance light, and to obtain output voltage having excellent S/N ratio.  
      Since the optical fiber  25  is used, it is possible to suppress the attenuation of reflection light, and illumination can be detected with high sensitivity. Since the reagent containing member  13  and the PD  23  are not in the same atmosphere (i.e., they are separated from each other), it is possible to reduce the influence of moisture (moisture caused by saliva) with respect to an interference filter (not shown) of the PD  23 .  
      Since the LED  21  and the PD  23  are mounted on the same surface of the substrate  47 , it is possible to efficiently assemble the substrate  47  (color depth measuring unit  9 ).  
      Next, operation for displaying a result of measurement of the amylase activity will be explained. The illumination of light measured by the color depth measuring unit  9  is output as a current value of the PD  23 . Thus, it is necessary to convert the current value into an amylase activity.  
      An electronic circuit substrate mounted on the enzyme activity measuring apparatus  1  has a function for storing a calibration curve and for converting the same into an activity of the amylase or into a target index.  
      The electronic circuit substrate also has a function for guiding the measuring procedure and a function as a real time clock.  
       FIG. 9  is a block diagram of a CPU substrate  100 .  FIG. 10  is a block diagram of a sensor substrate  121 . The CPU  101  includes a 256 kB flush ROM therein so that a program can be rewritten. An oscillator  103  supplies a clock signal to the CPU  101 . In this embodiment, the CPU  101  constitutes an enzyme activity detector which detects an amylase activity included in saliva.  
      A communicating unit  105  comprises an RS232C driver, and is used for outputting measurement data and for downloading a rewritable program. A clock unit  107  comprises a real time clock IC and produces a precise timing signal.  
      A storing unit  109  can store data concerning the measurement time and measurement result, and can output the data in response to request. A buzzer outputting unit  111  is a circuit which outputs sound when an error is generated and when it is necessary to encourage a user to carry out operation (for example, operation for completing the transcription of saliva).  
      A power supply  113  converts voltage of a battery mounted in the casing  1 A to required voltage, and comprises a circuit which supplies to the CPU  101 . A backup power supply  115  is used to back up data stored in the storing unit  109  and the clock unit  107 .  
      A liquid crystal display  117  displays thereon the operation menu, operation guidance, measurement result and the like. A switch  119  comprises a power supply switch, a cursor switch and a circuit which detects the operation of the switch.  
      As shown in  FIG. 10 , a sensor substrate  121  comprises a reference voltage generator  123  which produces reference voltage used for A-D conversion, an LED driver  125  for supplying constant current to the LED  21 , a PD amplifier  127  which converts the current value supplied from the PD  23  into a voltage value and amplifies the same, and a temperature detector  129 .  
      The sensor substrate  121  is provided with a switch operation detector  131  which detects the operation of a cover switch (limit switch operated by the projection  3 D) and the operation of a transcription-starting switch (limit switch operated by the projection  33 C).  
      Next, the operation for measuring the amylase activity using the enzyme activity measuring apparatus  1  will be explained.  
      As described above, the enzyme activity measuring apparatus  1  disposed the reagent containing member  13  and the saliva extracting sheet  15  including the saliva at a distance from each other. Next, the enzyme activity measuring apparatus  1  brings the reagent containing member  13  and the saliva extracting sheet  15  into contact with each other, and allows the reagent containing member  13  to transcribe a predetermined volume of saliva.  
      The enzyme activity measuring apparatus  1  measures color depth of the reagent in the reagent containing member  13  when predetermined time is elapsed after the transcription of saliva is started, and calculates the amylase activity included in saliva based on the measured color depth.  
      FIGS.  11  to  13  show the operation for measuring the amylase activity using the enzyme activity measuring apparatus  1 .  
      First, in step S 1 , a user turns on the power supply switch of the enzyme activity measuring apparatus  1 .  
      If the power supply switch is turned on, in step S 3 , the LED  21  provided on the substrate  47  is lit. In step S 5 , the CPU  101  is initialized. In step S 7 , error of backed up data is checked.  
      In step S 9 , a title is displayed on the LCD panel  117 A, and in step S 11 , the operation menu is displayed.  
      Next, in step S 13 , the operation state of the cover switch is detected. In step S 15 , it is determined whether the cover  3  is opened. If it is detected that the cover  3  is closed (Yes in step S 15 ), “OPEN COVER” is displayed on the LCD panel  117 A, and the procedure is returned to step S 13 .  
      If it is detected that the cover  3  is opened (No in step S 15 ), “SET UNIT COVER CLOSE” is displayed on the LCD panel  117 A in step S 19 , and it is detected in step S 21  whether the cover  3  is closed.  
      In reply to the display of “SET UNIT COVER CLOSE”, the user inserts the base material  27  having the saliva extracting sheet  15  into the holder  17 , and sets the holder  17  into which the base material  27  is inserted to a predetermined position of the base  29 . Then, the user closes the cover  3  and fixes the cover  3  using the hook  45 .  
      When the cover  3  is closed (Yes in step S 21 ), “CALIBRATING” is displayed on the LCD panel  117 A in steps S 23  and S 25 , and the enzyme activity measuring apparatus  1  is brought into its standby state until the output is stabilized (for example, 3 seconds).  
      In step S 27 , the enzyme activity measuring apparatus  1  irradiates the white portion of the base material  27  (back side of a portion of the base material  27  where the saliva extracting sheet  15  is provided) with light from the LED  21 , measures the output current value of the PD  23 , and converts the current value to the voltage value.  
      When the voltage value is higher than 4V (No in step S 29 ). “ERROR” is displayed on the LCD panel  117 A in step S 31 , and buzzer sounds.  
      On the other hand, if the output voltage is less than 4V (Yes in step S 29 ), the enzyme activity measuring apparatus  1  stores the measured voltage value in the storing unit  109  as reference voltage in step S 33 . In step S 35 , “PULL UP THE LEVER” is displayed on the LCD panel  117 A.  
      Based on the display in step S  35 , the user turns the transcription lever  41 A (to the position shown with phantom line in  FIG. 2 ). With this, the transcription of saliva is started.  
      In steps S 37  and S 39 , the enzyme activity measuring apparatus  1  determines whether the transcription of saliva is started (and or whether the transcription of saliva is being carried out) by means of the limit switch operated by the projection  33 C.  
      If the transcription lever  41 A is not turned, i.e., if the start of transcription of saliva is not detected (No in step S 39 ), the enzyme activity measuring apparatus  1  repeats the procedure from step S 35 .  
      On the other hand, if it is detected that the transcription of saliva is started (Yes in step S 39 ), in step S 41 , the enzyme activity measuring apparatus  1  starts the measurement of the transcription time (set T 0 ). In step S 43 , “TRANSCRIPTING” is displayed on the LCD panel  117 A.  
      In step S 45 , the enzyme activity measuring apparatus  1  detects whether 10 seconds (T 1 ) is elapsed after the start of transcription.  
      If 10 seconds are not elapsed from the start of transcription (No in step S 45 ), the enzyme activity measuring apparatus  1  repeats the procedure from step S 43 .  
      On the other hand, if 10 seconds are elapsed from the start of transcription (Yes in step S 45 ), the buzzer sounds in step S 47 . In step S 49 , “PUSH RELEASE BUTTON SLIDE THE SHEET” is displayed on the LCD panel  117 A in step S 49 .  
      In response to the beep in step S 47  or the display in step S 49 , the user turns the transcription lever  41 A, and removes the base material  27  from the holder  17  (enzyme activity measuring apparatus  1 ) and completes the transcription of saliva.  
      In steps S 51  and S 53 , the enzyme activity measuring apparatus  1  starts the measurement. That is, the enzyme activity measuring apparatus  1  allows the LED  21  to light, and irradiates the reagent containing member  13  with light and measures the reflection light by the PD  23 .  
      In step S 55 , the enzyme activity measuring apparatus  1  stores data concerning the measured reflection light in the storing unit  109 .  
      In step S 57 , the enzyme activity measuring apparatus  1  detects whether the transcription lever  41 A has returned to the position shown with solid line in  FIG. 2 . If the transcription lever  41 A has not yet returned to the position (No in step S 57 ), “PUSH RELEASE BUTTON SLIDE THE SHEET” is displayed on the LCD panel  117 A in step S 61 .  
      On the other hand, if it is detected that the transcription lever  41 A has returned to the position shown with solid line in  FIG. 2  (Yes in step S 57 ), in step S 59 , the measured value (amylase activity) and the voltage value based on measurement by the PD  23  are displayed on the LCD panel  117 A.  
      In step S 63 , the enzyme activity measuring apparatus  1  determines whether predetermined time (T 2 ) is elapsed from the time (time T 0 ) when the transcription of saliva is started.  
      If the predetermined time is not elapsed (No in step S 63 ), the enzyme activity measuring apparatus  1  repeats the procedure from step S 53 .  
      If the predetermined time is elapsed (Yes in step S 63 ), in step S 65 , the buzzer sounds and in step S 67 , “MEASURE COMPLETE” is displayed on the LCD panel  117 A.  
      In step S 69 , a list of measurement data is displayed on the LCD panel  117 A. The measurement data is data concerning the amylase activity, and is data concerning the voltage value measured in step S 27  and density of reagent (depth of formed color) calculated based on the voltage value measured in step S 53 .  
      In step S 71 , the enzyme activity measuring apparatus  1  detects whether the MODE button (not shown) is pushed. If the MODE button is pushed, the operation menu is again displayed on the LCD panel  117 A in step S 73 .  
      (Working Effect)  
      According to the enzyme activity measuring apparatus  1  of the first embodiment of the present invention described above, it is possible to precisely transcribe the predetermined volume of saliva to the reagent containing member  13 . Since the density of reagent (degree of formed color) in the reagent containing member  13  is measured when the predetermined time is elapsed after the saliva is transcribed, the amylase activity included in saliva can precisely be detected.  
      According to the enzyme activity measuring apparatus  1 , the flat surface portion  13 A of the reagent containing member  13  and the flat surface portion  15 A of the saliva extracting sheet  15  are disposed such as to be opposed to each other in parallel to each other, and the flat surface portion  13 A and the flat surface portion  15 A are brought into contact with each other for the predetermined time under the predetermined pressure. Therefore, it is possible to substantially constantly determine the transcription volume of saliva to the reagent containing member  13 .  
      According to the enzyme activity measuring apparatus  1 , the reagent containing member  13  and the saliva extracting sheet  15  are separated from each other using the holder  17 . Further, since the saliva is transcribed by deforming the holder  17  by a predetermined amount, the transcription operation of saliva, i.e., the measuring operation of the activity of the amylase is simplified.  
      Further, according to the enzyme activity measuring apparatus  1 , since the density of reagent included in the reagent containing member  13  can be detected by measuring the depth of color of the reagent, the density of reagent can easily be measured.  
      According to the enzyme activity measuring apparatus  1 , the cover  3  capable of opening and closing is provided for preventing the disturbance light from entering the color depth measuring unit  9 . Therefore, when the cover  3  is opened, it is easy to set the reagent containing member  13  and the holder  17  to the enzyme activity measuring apparatus  1 .  
      When the cover  3  is closed, the disturbance light can be blocked and the color of the reagent containing member  13  can precisely be detected. Since the cover  3  fixes the holder  17 , the structure of the enzyme activity measuring apparatus  1  is simple.  
      According to the color depth measuring unit  9  of the enzyme activity measuring apparatus  1 , the LED  21  irradiates the reagent containing member  13  with light uniformly, and the PD  23  receives the reflection light from diagonal direction with respect to the reagent containing member  13 . Therefore, it is possible to receive the uniform and stable reflection light, and the color of the reagent containing member  13  can precisely be measured.  
      According to the color depth measuring unit  9  of the enzyme activity measuring apparatus  1 , the PD  23  receives and measures the reflection light through the optical fiber  25 . Thus, the layout of the PD  23  can flexibly be designed. The filter (not shown) provided on the tip end of the PD  23  can be separated from the reagent containing member  13 , it is possible to prevent the filter which is vulnerable to water from being damaged.  
      According to the enzyme activity measuring apparatus  1 , since the saliva is used as sample, sample can be extracted easily (a subject person does not feel pain for example) with compared with a case in which blood or urine is used as the sample.  
      Further, according to the enzyme activity measuring apparatus  1  capable of easily measuring the amylase activity included in human&#39;s saliva, it is possible to provide simple and effective means which detects the stress level of a subject person.  
      Concretely, a subject person (user) measures the amylase activity included in the saliva which is extracted in the rest state, and the measured activity is stored in the enzyme activity measuring apparatus  1  as a reference value.  
      Then, the subject person measures the amylase activity in a predetermined state (state in which the subject person receives stress), and compares the measured activity and the reference value. If the measured activity is greater than the reference value, it can be determined that the subject person receives distress, and if the measured activity is smaller than the reference value, it can be determined that the subject person receives eustress.  
      As the difference between the reference value and the measured activity is greater, it can be determined that the received stress is also greater, and the degree of stress that the subject person is mentally receiving can also be determined.  
      By continuously measuring the amylase activity, it is possible to grasp the variation of stress with time. When a user receives distress, the amylase activity included in saliva is increased. In this case, it is possible to determine the degree of distress by the magnitude of positive time gradient.  
      When the user receives eustress, since the amylase activity is reduced, it is possible to determine the degree of stress by the magnitude of positive time gradient.  
      By continuously measuring the amylase activity, it is possible to grasp the variation in amylase activity before and after a specific stress is applied to a subject person, and it is possible to determine the magnitude of stress by the time and magnitude required until the activity is returned to the previous activity (reference value) before the stress is applied.  
     Second Embodiment  
      (Outline Structure of Enzyme Activity Measuring Apparatus)  
      Next, a second embodiment of the enzyme activity measuring apparatus according to the present invention will be explained.  FIG. 14  is a perspective view of an enzyme activity measuring apparatus  200  of the second embodiment of the invention. The enzyme activity measuring apparatus  200  is an improvement of the enzyme activity measuring apparatus  1  of the first embodiment of the invention.  
      A different portion of the enzyme activity measuring apparatus  200  as compared with the enzyme activity measuring apparatus  1  will mainly be explained, and explanation of the same structure and function as those of the enzyme activity measuring apparatus  1  will appropriately be omitted.  
      As shown in  FIG. 14 , the enzyme activity measuring apparatus  200  has a casing  220 . The casing  220  is provided at its surface with a cover opening button  250 , a LCD panel  270  and a switch  280 . The enzyme activity measuring apparatus  200  is operated by connecting four AAA batteries or AC power supply incorporated therein.  
      The LCD panel  270  has the same function as that of the LCD panel  117 A (see  FIG. 2 ) of the enzyme activity measuring apparatus  1 . The switch  280  is connected to the CPU  101  like the switch  119  (see  FIG. 9 ) of the enzyme activity measuring apparatus  1 .  
      A cover  210  of the enzyme activity measuring apparatus  200  is provided with a sample transcription unit  230  which pushes the holder  17  (see  FIG. 1 ). The holder  17  can be set on a base  229  (not shown in  FIG. 14 , see  FIG. 16 ) provided in the casing  220 .  
       FIG. 15  is a plan view of the enzyme activity measuring apparatus  200 . As shown in  FIG. 15 , the cover  210  can open and close around a hinge  215  (turning shaft).  FIG. 16  shows the cover  210  which is turned and opened around the hinge  215 .  
      As shown in  FIG. 16 , the sample transcription unit  230  of this embodiment is provided on the cover  210 . The sample transcription unit  230  is provided with a metal transcription pad  240  (pushing member) which pushes the holder  17  set on the base  229 . The base  229  constitutes the reagent/sample disposing unit of this embodiment. The base  229  has the same shape as that of the base  29  of the enzyme activity measuring apparatus  1 . In this embodiment, a heater  260  is provided below the base  229 . The heater  260  heats a sample held by the holder  17  set on the base  229  to a predetermined temperature (for example, 20° C.).  
      The enzyme activity measuring apparatus  200  (casing  220 ) is provided with a pair of hooks  257  (ends  257   e ). The cover  210  is provided with a pair of insertion holes  210   a  into which the hooks  257  are inserted in a state in which the cover  210  is closed.  
      The hooks  257  are biased in the insertion direction into the insertion holes  210   a . If the cover opening button  250  is pushed, the hooks  257  are pulled in toward the inside of the casing  220 . That is, the cover  210  is fixed in its closed state by the hooks  257 .  
      If the cover  210  is closed, an upper end  210   te  of the cover  210  abuts against an upper end  225   te  of an inner cover  225 . Similarly, a lower end  210   be  of the cover  210  abuts against a lower end  225   be  of the inner cover  225 .  
      (Cover Opening/Closing Mechanism)  
      Next, referring to  FIGS. 17 and 18 , a cover opening/closing mechanism of the enzyme activity measuring apparatus  200  will be explained.  FIG. 17  is a sectional view taken along the direction F 17 -F 17  shown in  FIG. 15 .  FIG. 18  is an explanatory view for explaining the operation of the cover opening/closing mechanism.  
      As shown in the drawings, the casing  220  is provided with a cover opening button  250 , a coil spring  251 , a push rod  252 , a lever  253 , a turning shaft  254 , a connecting pin  255 , a support shaft  256 , and hooks  257 .  
      The cover opening button  250  is pushed when the cover  210  is to be opened. That is, when the holder  17  into which the saliva extracting sheet  15  is inserted is to be set on the base  229  or when the measured holder  17  is to be removed from the base  229 , the cover opening button  250  is pushed.  
      The cover opening button  250  is connected to the push rod  252  inserted into the coil spring  251 . If the cover opening button  250  is pushed, the lever  253  is pushed to turn the lever  253 . In this embodiment, the cover opening button  250  and the push rod  252  constitute the cover opening button portion.  
      As shown in these drawings, the upper end  210   te  of the cover  210  is a convex end, and the upper end  225   te  of the inner cover  225  is concave end. That is, the convex upper end  210   te  is fitted into the concave upper end  225   te.    
      The lower end  225   be  of the inner cover  225  is slightly swells as compared with the casing  220 , and the lower end  225   be  abuts against the lower end  210   be  of the cover  210 .  
      The lever  253  is engaged with the hook  257 , and turns around the turning shaft  254 . The lever  253  moves the hook  257  in the insertion direction of the insertion hole  210   a  and in a direction opposite from the insertion direction. In this embodiment, the lever  253  constitutes the projecting member moving lever.  
      The connecting pin  255  connecting the lever  253  and the hooks  257  to each other is inserted into an upper edge of the lever  253 . The lever  253  biases the hooks  257  in the insertion direction of the insertion hole  210   a  by a spring provided in the lever  253 . In this embodiment, the turning shaft  254 , the support shaft  256  and the hooks  257  are made of metal to secure the strength.  
      The hooks  257  are supported by the support shaft  256 , and in a state in which the cover  210  is closed, the sample transcription unit  230  can move in a direction substantially perpendicular to the direction AR 10  (pushing direction) in which the sample transcription unit  230  pushes the holder  17 .  
      More concretely, as shown in  FIG. 18 , if the cover opening button  250  is pushed down in the direction AR 11 , the lever  253  turns around the turning shaft  254  in the direction AR 12 . The hooks  257  connected to the lever  253  through the connecting pin  255  are moved in the direction AR 13  (opposite from the insertion direction of the insertion hole  210   a ).  
      If the hooks  257  are moved in the direction AR 13 , the ends  257   e  of the hooks  257  are pulled out from the insertion hole  210   a . If the hooks  257  are pulled out from the insertion hole  210   a , the cover  210  turns in the direction AR 14  by the spring provided in the hinge  215 .  
      (Sample Transcription Unit)  
      Next, referring to  FIGS. 19 and 20 , the sample transcription unit  230  of the enzyme activity measuring apparatus  200  will be explained.  FIG. 19  is a side view of the sample transcription unit  230  as viewed from the direction F 19  shown in  FIG. 15 , and  FIG. 20  is an explanatory view for explaining the operation of the sample transcription unit  230 .  
      As shown in the drawings, the sample transcription unit  230  includes a cam  231 , a transcription lever  232 , a movable member  237 , a transcription pad  240  and a base plate  241 . The sample transcription unit  230  is assembled as a unit, and the assembled sample transcription unit  230  is mounted on the cover  210  using a screw.  
      The movable member  237  includes a pushing surface  237   pp  and a cam abutment surface  237   cp . The pushing surface  237   pp  is connected to the transcription pad  240  which pushes the holder  17 . The holder  17  holds the reagent containing member  13  and the saliva extracting sheet  15 . The cam abutment surface  237   cp  is opposed to the pushing surface  237   pp . The movable member  237  can move along the pushing direction into which the holder  17  is pushed.  
      The cam  231  turns around a turning shaft  234 . The cam  231  has a flat surface portion  231   p  on a portion of the outer peripheral surface thereof having a distance from the turning shaft  234  which is longer than other portion.  
      As shown in  FIG. 20 , the transcription lever  232  turns in the direction AR 15  (first direction), thereby bringing the flat surface portion  231   p  of the cam  231  and the cam abutment surface  237   cp  of the movable member  237  into abutment against each other.  
      More concretely, like the cam  231 , the transcription lever  232  can turn around the turning shaft  234 . If the transcription lever  232  turns in the direction AR 15 , the cam  231  which is adjacent to the transcription lever  232  turns around the turning shaft  234 , and the flat surface portion  231   p  abuts against the cam abutment surface  237   cp  of the movable member  237 .  
      A guide rod  238  is mounted on the base plate  241  so that the movable member  237  can move. The guide rod  238  is inserted into a coil spring  239  (second biasing member) which biases the movable member  237  toward the cam  231 .  
      The base plate  241  includes a retaining projection  241   a , a retaining projection  241   c  and a turning shaft support portion  241   e.    
      The retaining projection  241   a  is provided with a retaining hole  241   b . A coil spring  233  (first biasing member) for biasing the cam  231  such as to turn the cam  231  in the direction AR 17  (second direction) which is opposite from the direction AR 15  (first direction) is mounted to the retaining hole  241   b  and a retaining hole  231   a  provided in the cam  231 .  
      The retaining projection  241   c  is provided with a retaining hole  241   d . A coil spring  235  (third biasing member) for biasing the transcription lever  232  such that the transcription lever  232  turns in the direction AR 17  is mounted to the retaining hole  241   d  and a retaining hole  232   a  provided in the transcription lever  232 .  
      The turning shaft support portion  241   e  supports the both ends of the turning shaft  234  such that the turning shaft  234  can turn.  
      Next, referring to  FIG. 20 , the operation of the sample transcription unit  230  will be explained. If the user turns the transcription lever  232  in the direction AR 15 , the cam  231  turns around the turning shaft  234 , and the flat surface portion  231   p  abuts against the cam abutment surface  237   cp.    
      Since the flat surface portion  231   p  is provided on the outer peripheral surface having the longer distance from the turning shaft  234  than other portions, the movable member  237  is moved downward.  
      If the movable member  237  is moved downward, the transcription pad  240  which is connected to the pushing surface  237   pp  of the movable member  237  pushes the holder  17  to deform the same. If the holder  17  is deformed, the reagent containing member  13  (flat surface portion  13 A) and the saliva extracting sheet  15  (flat surface portion  15 A) held by the holder  17  come into contact with each other, and the transcription of saliva included in the saliva extracting sheet  15  is started.  
      Here, a load is applied to the movable member  237  (and transcription pad  240 ) in the direction of the cam  231  by reaction forces of the pushed and deformed holder  17  and the coil spring  239 . Thus, the flat surface portion  231   p  and the pushing surface  237   pp  are held in their abutted state, and the contact state between the reagent containing member  13  and the saliva extracting sheet  15 , i.e., the “transcription state of saliva” is held.  
      That is, the transcription lever  232  is held at the position P 2 . The transcription lever  232  can freely turn between a position P 1  and a position P 3  where the end  232   e  of the transcription lever  232  come into contact with the movable member  237 .  
      The “transcription state of saliva” is released if the user lightly pushes the transcription lever  232  located at the position P 2  downward (direction P 1 ). More specifically, the transcription lever  232  is biased by the coil spring  235  such that the transcription lever  232  turns in the direction AR 17 . The cam  231  is biased such as to turn in the AR 17  by the coil spring  233 .  
      Thus, if the transcription lever  232  is lightly pushed, the transcription lever  232  and the cam  231  are turned in the direction AR 17 , and the “transcription state of saliva” is released.  
      When the cover  210  (see  FIG. 16 ) is not closed, the movable member  237  (and transcription pad  240 ) can not obtain the reaction force from the holder  17 . The cam  231  is biased by the coil spring  233  such as to turn in the direction AR 17 . That is, the sample transcription unit  230  is constituted such that when the cover  210  is not closed, the flat surface portion  231   p  and the pushing surface  237   pp  are prevented from being held in a state in which they abut against each other.  
      (Sample Temperature Compensating Mechanism)  
      Next, a sample temperature compensating mechanism of the enzyme activity measuring apparatus  200  will be explained. The enzyme activity measuring apparatus  200  has substantially the same CPU substrate  100  and sensor substrate  121  (see  FIGS. 9 and 10 ) as those of the enzyme activity measuring apparatus  1  of the first embodiment.  
      The sample temperature compensating mechanism of the enzyme activity measuring apparatus  200  has (1) a function for correcting activity of detected amylase, and (2) a function for keeping sample warm.  
      (1) Correction of Amylase Activity  
      The temperature detector  129  of the enzyme activity measuring apparatus  200  (see  FIG. 10 ) detects the temperature of sample which is the temperature of the reagent containing member  13  to which the sample, i.e., the saliva is transcribed.  
      More specifically, a photodiode  26  (PD  26 , hereinafter) for detecting infrared rays is connected to the temperature detector  129 .  
       FIG. 21  is a schematic block diagram of a color depth measuring unit  9 ′ provided on the enzyme activity measuring apparatus  200 . The color depth measuring unit  9 ′ comprises the color depth measuring unit  9  ( FIG. 5 ) of the enzyme activity measuring apparatus  1  to which the PD  26  is added.  
      The PD  26  detects the intensity of the infrared rays emitted from the reagent containing member  13 . The temperature detector  129  connected to the PD  26  detects the temperature of the sample by calculating the temperature emitted from the reagent containing member  13  based on the intensity of the detected infrared rays.  
      The storing unit  109  (see  FIG. 9 ) of the enzyme activity measuring apparatus  200  also can store sample temperature correcting data in which the sample temperature detected by the temperature detector  129  and a correcting rate for correcting the amylase activity detected by the CPU substrate  100  are associated with each other. In this embodiment, the storing unit  109  constitutes a sample temperature correcting data storing unit.  
       FIG. 22A  is a graph showing the relation (temperature characteristics) between the sample temperature and the activity rate of the amylase included in the sample. In  FIG. 22A , the the amylase activity at 37° C. (human&#39;s body temperature) is indicated with 100%.  
      As shown in  FIG. 22A , if the sample temperature is lowered to 10° C. for example, the amylase activity is reduced (actually measured value) by about 20% of the amylase activity at 37° C. That is, the activity of amylase included in sample (saliva) largely relies upon the temperature.  
      That is, an error in measurement becomes greater depending upon the temperature at the time of measurement. Therefore, in this embodiment, sample temperature correcting data shown in  FIG. 22B  is used.  
       FIG. 22B  shows a correcting curve of sample temperature determined based on the temperature characteristics. The correcting curve is determined as being 25° C. as a reference because a general room temperature and the calibration curve are set to 25° C. The reference temperature may be other than 25° C.  
      The CPU  101  (see  FIG. 9 ) of the enzyme activity measuring apparatus  200  can correct the activity of the detected amylase based on the sample temperature detected by the temperature detector  129  and the sample temperature correcting data stored in the storing unit  109 . In this embodiment, the CPU  101  constitutes an activity correcting unit.  
      More specifically, activity of detected amylase is corrected by processing flow shown in  FIG. 23 .  FIG. 23  is a flowchart of operation to be carried out between steps S 53  and S 55  in the operation flow of the enzyme activity measuring apparatus  1 .  
      As shown in  FIG. 23 , in step S 54   a , the enzyme activity measuring apparatus  200  converts, into amylase activity, a value of output voltage which is a voltage value from which a current value output by the PD  23  is converted. As described, the PD  23  measures light reflected from the reagent containing member  13 .  
      In step S 54   b , the enzyme activity measuring apparatus  200  detects the temperature (sample temperature) of the reagent containing member  13  to which the saliva is transcribed. More specifically, the enzyme activity measuring apparatus  200  detects the intensity of infrared rays emitted from the reagent containing member  13  (test paper) by the PD  26 .  
      In step S 54   c , the enzyme activity measuring apparatus  200  calculates a correcting rate of amylase activity based on the sample temperature detected in step S 54   b  and the stored sample temperature correcting data (see  FIG. 22B ).  
      The procedure in steps S 54   b  and S 54   c  can be carried out concurrently with the procedure in step S 54   a , or before the procedure in step S 54   a.    
      In step S 54   d , the enzyme activity measuring apparatus  200  corrects the amylase activity converted in step S 54   a  using the correcting rate calculated in step S 54   c.    
      In step S 54   e , the enzyme activity measuring apparatus  200  displays the activity of the corrected amylase on the LCD panel  270 .  
      (2) Keeping of Temperature of Sample  
      By correcting the amylase activity, an error in the measurement caused by the temperature at the time of measurement can be suppressed. However, when the temperature at the time of measurement is low (lower than 10° C.), the activity of amylase is largely lowered as shown in  FIG. 22A .  
      If the activity of amylase is largely lowered, although amylase is included, reagent included in the reagent containing member  13  does not react in some cases. In this case, the above-described correction can not be used.  
      Thus, the enzyme activity measuring apparatus  200  is provided with a heater  260  which heats the sample (saliva) set in the base  229  to a predetermined temperature (for example, 20° C.).  
      More specifically, as shown in  FIG. 24 , the heater  260  comprising a heating wire is provided below the base  229 . In order to efficiently transfer the heat generated by the heater  260  to the reagent containing member  13 , the base  229  is made of aluminum alloy having excellent thermal conductivity.  
      When the CPU  101  (see  FIGS. 9 and 10 ) of the enzyme activity measuring apparatus  200  detects that the sample temperature reaches the predetermined temperature, the CPU  101  can stop the operation of the heater  260 . In this embodiment, the CPU  101  constitutes a heater controller.  
      Since the enzyme activity measuring apparatus  200  has the heater  260 , the power consumption of the enzyme activity measuring apparatus  200  is increased. Thus, a separate battery pack can be connected to the enzyme activity measuring apparatus  200 .  
      (Working Effect)  
      According to the cover opening/closing mechanism provided in the enzyme activity measuring apparatus  200 , the hooks  257  are constituted such that the sample transcription unit  230  can move in the direction substantially perpendicular to the direction AR 10  (pushing direction) in which the sample transcription unit  230  pushes the holder  17 .  
      Thus, even when a load caused when the holder  17  is pushed is applied to the hooks  257 , it is possible to prevent the hooks  257  from coming out from the cover  210  (insertion hole  210   a ) and prevent the cover  210  from opening.  
      That is, according to the enzyme activity measuring apparatus  1 , since the pushing direction in which the holder  17  is pushed and the direction in which the load is applied to the hook  45  are the same, if the transcription lever  41 A is turned to push the holder  17 , the hook  45  comes out and the cover  3  is opened in some cases. According to the enzyme activity measuring apparatus  200 , it is possible to reliably prevent the cover  210  from opening when the holder  17  is pushed.  
      According to the cover opening/closing mechanism, since the cover opening button  250  is provided, the user can easily open the cover  210  only by pushing the cover opening button  250 .  
      According to the cover opening/closing mechanism, since the disturbance light is prevented from entering by the shapes of the cover  210  (upper end  210   te , the lower end  210   be ) and the inner cover  225  (upper end  225   te , the lower end  225   be ), the change in color of the reagent containing member  13  can precisely be measured.  
      According to the sample transcription unit  230  provided in the enzyme activity measuring apparatus  200 , even if the transcription lever  232  is turned, the cam  231  and the transcription pad  240  (and movable member  237 ) are pulled back to the position before the transcription lever  232  is turned as long as the holder  17  is not set on the base  229  and the cover  210  is not closed.  
      Therefore, as the holder  17  is not set on the base  229  and the cover  210  is not closed (as long as the cover  210  is not opened), it is possible to prevent the holder  17  from being pushed and from the transcription of saliva from being started.  
      That is, according to the enzyme activity measuring apparatus  1 , the transcription lever  41 A can be turned to push the holder  17  even if the cover  3  is not closed, the transcription of saliva is started at unintentional timing in some cases. According to the enzyme activity measuring apparatus  200 , it is possible to reliably prevent the transcription of saliva from being started at unintentional timing.  
      The sample transcription unit  230  is assembled as a unit and the assembled sample transcription unit  230  is mounted on the cover  210  using a screw, the sample transcription unit  230  can be assembled and the cover  210  can be mounted efficiently as compared with the enzyme activity measuring apparatus  1  in which various members are individually mounted on the cover  3 .  
      According to the sample transcription unit  230 , the user can turn the transcription lever  232  and the cam  231  in the direction AR 17  only by lightly pushing the transcription lever  232 , and the “transcription state of saliva” is released. Thus, the returning operation of the transcription lever  232  is extremely simple.  
      According to the sample temperature compensating mechanism provided in the enzyme activity measuring apparatus  200 , since the activity of the detected amylase is corrected by the sample temperature correcting data, it is possible to obtain an activity having small measurement error irrespective of the temperature at the time of measurement.  
      According to the sample temperature compensating mechanism, since the heater  260  is provided, the enzyme activity measuring apparatus  200  can be utilized in various situations irrespective of measuring environment (for example, outdoor).  
      Although the contents of the present invention have been disclosed based on the first and second embodiments, it should not be understood that the description and drawings forming a portion of the disclosure limit the present invention. Various modifications will be apparent for a person skilled in the art from this disclosure.  
      For example, the sample transcription unit  7  and the sample transcription unit  230  can be provided as a single sample transcription apparatus. The color depth measuring unit  9  and the color depth measuring unit  9 ′ can be provided as a single color measuring apparatus.  
      The present invention includes various modes of carrying out the invention which are not described here of course. Therefore, the technical scope of the present invention is determined only by the invention specifying matters according to patent claims from the above explanation.