bluuebunny/crossref_metadata_2025_split huggingface dataset:
EXPERIMENTAL PNEUMONIA IN MICE FOLLOWING THE INHALATION OF STREPTOCOCCUS HÆMOLYTICUS AND OF FRIEDLÄNDER'S BACILLUS
Authors: Stillman Ernest G. , Branch Arnold 
Published: June 2004

The results of these experiments support the previous observations that mice react in different ways to the inhalation of different bacteria. If normal mice are sprayed with hemolytic streptococci or Friedländer's bacillus, these organisms may be recovered from the lungs and heart's blood for a number of days after exposure. A large number of mice so exposed die of a septicemia during the 30 days following spraying. Consolidation of one or more lobes is not rare. If normal mice are exposed to an atmosphere of pneumococci, however, the organisms rapidly disappear from the lungs and only an occasional mouse succumbs to pneumococcus septicemia. In order to cause the pneumococcus to invade, the mice must first be alcoholized. If mice are first alcoholized and then exposed to a pneumococcus atmosphere, the pneumococci persist for a longer time in the lungs and a number will die of septicemia, a state of affairs which resembles that seen after the administration to normal mice of the other two organisms studied. In order to produce pneumococcus lobar consolidation, however, the mice must be first partially immunized and then allowed to inhale the organisms while under the influence of alcohol. A large percentage of both the normal and immune mice so alcoholized die within 5 days of exposure.
There also appears to be a definite relation between the mortality and the length of time inspired bacteria persist in the lungs. Whether this lag in removal allows multiplication of the bacteria and massive infection to occur has not been determined. Following inhalation of pneumococcus, the organisms were either removed rapidly and without apparent detriment to the animal, or, as in the case of the alcoholized mice, invasion occurred, in which event the mouse usually succumbed rapidly, localization in the lung only occurring in partially immune animals. In the case of the hemolytic streptococci and Bacillus friedlænderi, however, the whole process of removal and infection seems to be slower. Infection and pneumonia occurred more often. These organisms seem to possess much greater invasive power when inhaled than the pneumococcus, though on intraperitoneal or subcutaneous inoculation, pneumococcus is highly virulent for normal mice.
PATHOLOGY OF THE EXPERIMENTAL PNEUMONIAS IN MICE FOLLOWING INHALATION OF STREPTOCOCCUS HÆMOLYTICUS, OF FRIEDLÄNDER'S BACILLUS, AND OF PNEUMOCOCCUS
Authors: Branch Arnold , Stillman Ernest G. 
Published: June 2004

1. Pulmonary consolidation may be produced in normal mice by the inhalation of Friedländer's bacillus or Streptococcus hæmolylicus.
2. The initial lesion is in both instances interstitial in character and the spread is by way of the interstitial tissue, though the ultimate consolidation may come to resemble in the gross a lobar pneumonia.
3. The lesions grossly and microscopically may be distinguished from the lobar consolidation associated with pneumococcus infection of the lung.
4. Friedländer's bacillus and Streptococcus hæmolyticus give rise to pneumonia in mice previously normal, whereas the pneumococcus produces pulmonary lesions only under special circumstances, as when the animals are alcoholized after partial immunization.
DISTINCTIVE CHARACTERISTICS OF INFECTIONS PRODUCED BY TREPONEMA PERTENUE IN THE RABBIT
Authors: Pearce Louise , Brown Wade H. 
Published: June 2004

From a study of rabbits inoculated intratesticularly with two strains of treponemata derived from patients suffering from clinical yaws, it was found that a characteristic feature of the reaction to the infection was a well marked periorchitis of a granular or finely nodular type with or without a diffuse involvement of the tunic. While lesions of the testicular parenchyma also occurred they were relatively inconspicuous and consisted either of a minor diffuse orchitis which was usually followed by atrophy and fibrosis of the organ, or of small nodules; or there might be a combination of diffuse and nodular lesions. The granular periorchitis could be recognized clinically almost as soon as any change could be detected in the testicle, that is, about 3 weeks after inoculation; in the following month the covering of the testicle became studded with numerous tiny indurated nodules. Subsequently regression and healing took place and in the majority of animals no lesions were found 3 months after inoculation. In some animals residual lesions persisted for as long as 6 months. The granular periorchitis was a practically constant feature of the infection and was unlike any lesion of the tunic observed in experimental syphilis of the rabbit. Treponemata were numerous in the lesions of the tunic and somewhat less so in the testicle itself.
Dissemination of organisms to the uninoculated testicle and to the inguinal lymph nodes was demonstrated by animal inoculation although the clinical signs of a metastatic orchitis and periorchitis were slight and a lymph adenitis was an inconstant feature of the infection. Generalized lesions in remote parts of the body, similar to those occurring in experimental syphilis of the rabbit, were not observed.
THE RELATIONSHIP BETWEEN THE GROWTH CAPACITY OF PRIMARY TUMORS AND THE DISTRIBUTION OF METASTASES OF A TRANSPLANTED TUMOR OF THE RABBIT
Authors: Van Allen Chester M. 
Published: June 2004

As an adjunct to the study of a transplantable malignant tumor of the rabbit an index of malignancy has been developed which has proven useful in evaluating the severity of the disease for the purpose of statistical investigations.
The index consists of two figures, one of which expresses the growth capacity of the primary lesion on a volume basis, and the other the extent of the metastatic lesions according to the distribution of peripheral tumors. In the present communication these two values for each animal are utilized for the study of the relationship existing between the size of the primary tumor and the distribution of metastases in this experimental tumor. The data from a group of 128 rabbits form the basis of the analysis. These animals represent three entire series that had been used for the purposes of other experiments at various times, all, however, conducted under carefully controlled uniform conditions. The indices of malignancy of these animals were analyzed by means of graphs, in which individual values are preserved while at the same time investigation of mass behavior is permitted.
From this analysis it is concluded (1) that the severity of the disease as a whole is very irregular among individuals of a series and from series to series, and (2) that the relationship between the extent of the primary lesions and that of the secondary lesions is inconstant among individuals but assumes definite proportions when the data are viewed in the mass. For the mass proportion between the two phases of the disease is predominatingly a direct one, but in certain small groups of seriously affected rabbits the proportion shows a tendency to reversal, while, in addition, there occurs a reduction in the rate of growth of the primary tumor, which reduction, together with the reversal in relationship, appears to be more pronounced from series to series as malignancy increases.
An attempt has been made to account for these results in the light of what has been ascertained of the modes of defense of the rabbit host against the inroads of the cells of this transplanted tumor.
EXPERIMENTAL OBSTRUCTION OF THE JEJUNUM
Authors: Haden Russell L. , Orr Thomas G. 
Published: June 2004

Chemical changes are reported occurring in the blood of animals with obstruction of the jejunum, in which distilled water or sodium chloride solutions were introduced directly into the lumen of the intestine below the point of obstruction.
Distilled water given daily from the beginning of the obstruction, had no influence on the development or course of the toxemia.
1 and 2 per cent salt solutions prevented a toxemia in uncomplicated cases. One animal so treated lived 30 days.
Distilled water, given after the onset of toxemia, did not alter the progress or outcome of the toxemia.
10 per cent sodium chloride solution, administered after the onset of toxemia, controlled it in most cases for a long period.
Hydrochloric acid had no effect on the course of the toxemia.
SURFACE TENSION OF SERUM
Authors: du Noüy P. Lecomte 
Published: June 2004

1. The injection of antigen into an animal determines a gradual change in the blood fluid which finds expression in two physicochemical manifestations that can readily be followed, namely a decrease in the static value of the surface tension of serum solutions, and a special form of crystallization when serum diluted with isotonic sodium chloride solution is allowed to evaporate under certain conditions.
2. The change in the blood is at a maximum around the 13th day after the first antigen injection, and decreases progressively thereafter until it can no longer be observed, which is usually around the 30th day.
3. The change follows the same course, whether a single large injection of antigen is made, or many smaller ones. It begins at the same time in either case, it comes to a maximum after the same period, and in its subsequent course it is not affected by the reinjection of antigen. The manifestations of the change would appear to be independent of the presence of antigen in the circulation.
4. The mean length of the protein molecules of the immune serum obtained after the injection of the antigen dealt with is little if at all different from that of the protein molecules of normal serum.
5. It is possible that this reaction is independent of the antibody formation.
MICROBIC VIRULENCE AND HOST SUSCEPTIBILITY IN PARATYPHOID-ENTERITIDIS INFECTION OF WHITE MICE
Authors: Webster Leslie T. 
Published: June 2004

1. Survivors of an experimental mouse typhoid infection, selected and bred for a number of consecutive generations, give birth to offspring which are more resistant to the disease than a random group of the same inbred race.
2. Offspring of females most susceptible to this infection give birth to individuals which are more susceptible than a group of similar unselected mice.
STUDIES IN EXPERIMENTAL SYPHILIS
Authors: Chesney Alan M. , Kemp Jarold E. 
Published: June 2004

Syphilitic rabbits can be treated with arsphenamine in such a manner as to render the lymph nodes incapable of transmitting the infection to normal rabbits. This can be accomplished if treatment is begun either early or comparatively late in the course of the disease. If treatment is begun early, the animals are almost uniformly susceptible to a second infection, whereas, if it is begun late, they are almost uniformly refractory to a second infection. It is suggested that this refractory state in rabbits may be explained by the existence of an acquired immunity which persists after the abolition of the disease, rather than to the persistence of the first infection.
It would appear that it is possible under certain conditions to reinoculate rabbits and produce generalized infection without producing any lesion at the portal of entry.
STUDIES IN EXPERIMENTAL SYPHILIS
Authors: Chesney Alan M. , Kemp Jarold E. ,   With the Assistance of Allan K. Poole, M.D.
Published: June 2004

Simultaneous transfers to the testes of normal rabbits of circulating blood, heart muscle, liver, brain, spleen and bone marrow (mixed), inoculated testicle, and popliteal lymph nodes from a series of untreated syphilitic rabbits, demonstrated the persistence of the original infection unifomnly in the lymph nodes and less regularly in the liver, mixed spleen and bone marrow, and testis originally inoculated. In one instance the circulating blood was found to be infectious. Transfer of similar tissues from syphilitic rabbits treated with arsphenamine late in the course of the disease failed to disclose syphilitic infection of any of these tissues. In one animal, in which keratitis developed both before and after treatment, the blood, internal organs, and lymph nodes were found to be non-infectious in spite of the fact that the cornea was shown to be the site of a syphilitic inflammation. Transfer of lymph nodes or internal organs of treated syphilitic rabbits is probably the best method of evaluating an antisyphilitic agent, but it must be supplemented by careful observation of treated animals over an appreciable interval of time following treatment.
The results of this study support the idea that failure to reinoculate a treated syphilitic animal does not necessarily mean the existence of the first infection but might beinterpreted as indicating the presence of an acquired resistance which persists in rabbits in which no trace of the first infection can be demonstrated.
ORGAN WEIGHTS OF NORMAL RABBITS
Authors: Brown Wade H. , Pearce Louise , Van Allen Chester M. 
Published: June 2004

In November, 1921, a systematic study of normal rabbits was undertaken as a part of a more general investigation dealing with the subject of the animal organism in relation to disease. The present paper on organ weights is based on results obtained from a study of 350 male rabbits killed and examined between January 1, 1922, and July 1, 1924. Methods of conducting the experiments are described and the results are summarized in the form of a table and a series of text-figures.
The organs studied were the heart, liver, kidneys, spleen, thymus, testicles, brain, thyroid, parathyroids, suprarenals, hypophysis, pineal gland, and representative groups of lymph nodes.
The results recorded include maximum, minimum, and average weights, the median, the mode, the standard deviation, the probable error, the coefficient of variation, and the percentage distribution of organs of different weights.
No final conclusions are drawn but it is pointed out that the results obtained are comparable to those that have been reported from similar studies of organ weight in man. Attention is also directed to the tendency to the occurrence of wide variations in the weights of nearly all organs, and to an apparent difference in the degree of correlation that exists between organ weight and body weight in the case of certain organs. In this connection it is pointed out that within certain limits the weight of the brain, in particular, and of other organs to a lesser degree appears to be independent of body weight.
The results recorded in this paper are regarded as representing approximate values which are affected by numerous conditions for which correction should be made. These conditions will be considered in subsequent papers.
STUDIES ON UROBILIN PHYSIOLOGY AND PATHOLOGY
Authors: Elman Robert , McMaster Philip D. 
Published: June 2004

A variety of evidence is presented, all of which supports the view that in the uninfected animal the intestinal tract is the only place of origin of urobilin, not merely under normal circumstances, but when there is biliary obstruction. Animals rendered urobilin-free by collection of all of the bile from the intubated common duct remain urobilin-free even after severe hepatic injury.
In our experiments urobilinuria was never found after liver damage except when bile pigment was present in the intestine. Thus, for example, it appeared during the first days after Ugation of the common duct, but disappeared as the stools became acholic. When this had happened a small amount of urobilin-free bile, given by mouth, precipitated a prompt urobilinuria. After obstruction of the duct from one-third of the liver, mild urobilinuria was found, but no bilirubinuria. In animals intubated for the collection of a part of the bile only, while the rest flowed to the duodenum through the ordinary channels, liver injury caused urobilinuria, unless indeed it was so severe as to lead to bile suppression, when almost at once the urobilinuria ceased, though the organism became jaundiced.
The evidence here presented, when taken with that of our previous papers, clearly proves that urobilinuria is an expression of the inability of the liver cells to remove from circulation the urobilin brought by the portal stream, with result that the pigment passes on to kidney and urine. Urobilinuria occurs with a far less degree of liver injury than does bilirubinuria.
Our work has, for the most part, been carried out with animals having uninfected livers and bile passages. But the influence of cholangitis with infection has been briefly discussed in the light of some preliminary observations. The influence of infection on the place of formation of urobilin and on the occurrence of urobilinuria will form the subject of another communication.
THE INFLUENCE OF THE AUTONOMIC NERVOUS SYSTEM ON THE FUNCTION OF THE THYROID GLAND
Authors: Crawford J. Hamilton , Hartley J. N. J. 
Published: June 2004

1. There is a marked individual variation in the histological structure of the thyroid gland of rabbits examined at the same season under standard conditions. Although the microscopic appearance varies in different rabbits, the structure of the two lobes in the same animal does not differ. The variations are seen principally in the size and shape of the vesicles and in the quantity and character of the colloid.
2. With one lobe as a control no histological changes in the other lobe have been observed following section or stimulation of either the cervical sympathetic or the vagus and its branches.
THE HISTOLOGICAL CHANGES IN THE THYROID GLAND OF THE RABBIT FOLLOWING LOBECTOMY
Authors: Crawford J. Hamilton , Hartley J. N. J. 
Published: June 2004

1. In a series of rabbits the changes which took place in the histology of the left lobe of the thyroid gland after excision of the right lobe have been studied at varied intervals of time. 2 days after the removal of one lobe the other lobe showed a slightly increased colloid content, an increased vacuolation of the colloid, and a slight increase in the size of the epithelial cells. At the end of a week the vesicles were greatly increased in size, distended with colloid, and the epithelial cells were flattened, while after 3 to 4 months signs of compensatory hypertrophy were present.
2. The changes observed were uninfluenced by division of the vagus or cervical sympathetic.
AN EXPERIMENTAL STUDY OF THE RELATION OF THE OVARY TO FAT METABOLISM
Authors: Burrows Montrose T. , Johnston Charles G. 
Published: June 2004

From these observations there seemed to be little doubt that the follicular fluid of the ovary contains an active growth-stimulating substance and one capable of initiating an active digestion of a foreign fat, which might otherwise remain unabsorbed for an indefinite time in the tissues of these animals (2).
We have not attempted to ascertain whether this substance exciting growth and a digestion of the oil is the same or in any way related to the substance exciting estrus in these animals. That it may be a different substance from the estrus-exciting substance is suggested, however, by the fact that a similar excitant of growth and fat digestion has recently been extracted by the same method from the corpus luteum of pigs. These extracts of corpora lutea have not excited estrus in spayed rats.
In the one rat in which the pure oil was absorbed, the cells did not invade the oil, but the capsule remained cellular and the oil gradually disappeared from the space. In these experiments in which the active substance was added to the oil the cells have always invaded the oil.
PHYSIOLOGICAL ONTOGENY
Authors: Cohn Alfred E. , Murray Henry A. ,   With the Assistance of Alma Rosenthal.
Published: June 2004

1. Observations on tissue cultures of heart muscle from chicken embryos indicate that in general the growth rate of the individual cells decreases with age. The negative acceleration of growth is greatest at the beginning of life as in the intact embryo.
2. The latent period before growth commences increases with the age of the implanted tissue, but in a different fashion. The acceleration of the latent period is greatest near the end of the incubation period, thus demonstrating that the factors determining the initiation of growth and those determining the extent of growth are not similar.
PHYSIOLOGICAL ONTOGENY
Authors: Cohn Alfred E. ,   With the Assistance of Edith L. Wile.
Published: June 2004

These experiments show, then, that there are changes in rate which take place during the incubation period and that the direction of the curve expressing them changes in an orderly fashion. No attempt has yet been made to ascertain the influences operative in bringing about these alterations. It is our intention, however, to attempt to correlate them with such processes as changes in the rate of the general metabolism of the body, changes in structure of the heart muscle, and if possible with changes in the inherent dynamics of the muscle.
It will be seen that the number of experiments at a given age is relatively speaking small. The temperature in spite of the precaution mentioned has likewise not been uniform, the range in the greatest number (38) of experiments having been 38°C. ± 1°. A few (four) counts have been made when the temperature was as low as 33.6°C. and a few (two) also at a temperature as high as 40°C.
Although a curve as smooth as the one which has been drawn in all probability represents the general course of heart rate change, an explanation of the deviations which have been found is desirable. At least two influences which may be operative suggest themselves. First may be considered the effect of the unavoidable injury incident to cutting a window in the shell and removing so much of the shell membrane as to make the object visible. It has been a uniform practise to discard those eggs in which hemorrhage took place, so that if opening the egg has a share in the difficulty, this operation may be thought of as exerting a mechanical stimulus on a nervous or other controlling mechanism. But whether, especially at the early ages, a mechanism of such a nature exists within the embryo, we do not know. The search for one lies for the present beyond the range of our interest.
A second influence responsible for the relatively large deviation in rate from the average may be that of fluctuations in temperature. The air of the room in which the observations were made was, in a given situation, fairly uniform at 38°C. ± 1.0°. as the temperature records show. In the earlier experiments the temperature was read at a distance about 1 foot away from the egg. Between this point and the egg a difference unknown to us may well have existed. It is improbable, however, that it can have been more than 2°C., that is to say, 38° ± 2°. Roughly if the change in rate is approximately 15 beats per degree a maximum deviation of 30 beats may be expected. In point of fact a deviation as great as this did not take place. In later experiments the temperature was read in the immediate vicinity of the eggs, so that a correction can be made more accurately.
There is in all probability a high degree of uniformity in the rate of the heart of the chicken embryo at each stage of development, although variation is also found. What the extent of the deviation is that may properly be encountered we do not yet know. It is desirable to pursue this subject further. Observations will accordingly be made and will be reported later.