bluuebunny/crossref_metadata_2025_split huggingface dataset:
EXTRACTION OF ACID‐SOLUBLE COLLAGEN FROM GRASS CARP (CTENOPHARYNGODON IDELLA) SKIN
Authors: WANG LINGZHAO , YANG BAO , DU XIUQIAO 
Published: December 2008

ABSTRACT Grass carp is a freshwater fish species widely known by consumers over the world. Its skin has abundant collagen which has many healthy effects. Four variables (acetic acid concentration, temperature, time, solvent to material ratio) were taken to investigate their effects on the extraction efficiency of collagen from grass carp skin. From the results obtained, each of them showed a significant role in the extraction. The yield of collagen increased with the increase of acetic acid concentration to 0.5 M, and thereafter decreased. Elevation of temperature during extraction could also lead to the increase of collagen yield. However, when the temperature was above 20C, a negative effect was observed. The yield of collagen increased with the extension of time, especially when the time was shorter than 24 h. A positive relation was also observed between solvent to material ratio and yield of collagen. PRACTICAL APPLICATIONSGrass carp is widely consumed over the world for its delicious taste and healthy effect. A large amount of collagen exists in the skin tissues. Development of collagen from grass carp skin can bring added value for the fish processing industry. In this work, extraction of collagen from grass carp skin was investigated and effects of acetic acid concentration, temperature, time and solvent to material ratio on the extraction efficiency were determined. The results indicated that the above variables were influential for the extraction process. It is important to define the level of these variables in practical application so that the extraction efficiency can be improved, and a time‐saving, cost‐efficient process can be obtained.
ISOLATION AND SELECTION OF ETHANOL‐RESISTANT AND OSMOTOLERANT YEASTS FROM REGIONAL AGRICULTURAL SOURCES IN MEXICO
Authors: ORTIZ‐ZAMORA O. , CORTÉS‐GARCÍA R. , RAMÍREZ‐LEPE M. , GÓMEZ‐RODRÍGUEZ J. , AGUILAR‐USCANGA M.G. 
Published: December 2008

ABSTRACT In Mexican alcohol distilleries using sugarcane molasses, one reason for low alcoholic fermentation efficiency is the use of inferior yeast cultures. The objective of the present study was to isolate and select yeast strains from alcoholic fermentations of natural sources (sugarcane molasses, grape juice, cane juice and pineapple) from Veracruz city market and Mexican distilleries, and to evaluate their performance under laboratory conditions in an effort to select superior strains for industrial fermentations. Ethanol production, glucose composition, growth rate, “Killer” activity, ethanol and glucose tolerance of the most promising strains were monitored on synthetic and molasses media. A total of 112 yeast strains were isolated by their capacity to produce ethanol, and from these, only 58 were selected on the basis of best ethanol theoretical yields (88–96%). These strains were exposed several times to high concentrations of glucose and ethanol in order to select ethanol‐ and glucose‐tolerant yeast; 10 were obtained that adapted best to these conditions and that showed “Killer” activity. Of these strains, U3‐11, M11, JC10 and U2‐10 (obtained from grape juice, sugarcane molasses and cane juice) demonstrated the highest adaptation to both ethanol (5–7% w/v) and glucose (20% w/v). The maximum yield obtained was 0.46 g/g (90% theoretical yield) in a 20‐L bioreactor with cane molasses under nonsterile conditions. PRACTICAL APPLICATIONSThe selected yeasts could be introduced into industrial processes in Mexican distilleries using sugarcane molasses in order to improve productivity and diminish contamination problems.
The Nature of the Growth‐Promoting Substances in the Embryonic Tissue Juice.
Authors: FISCHER ALBERT 
Published: December 2008

Summary.

Twenty years of investigations (hitherto not published) on the chemical and physical nature of the growth‐promoting substance in the embryonic tissue juice are summarized by the author.
The use of various methods for determination of the activity of the substances is discussed.
Fractionation experiments on genuine chick‐embryo juice are described.
On account of the extreme lability of the active substances, special methods were devised for obtaining sterile, active fractions. In spite of all precautions a purification was not obtained.
It meant a great progress of the work, when it was found ‘that the carefully desiccated tissue juice Was resistant to extraction with chloroform, benzene a. o., whereby inactive fats and lipoids were removed and the extract rendered sterile.
Purification experiments Were undertaken with large quantities of dried, fat‐free beef‐embryo extract. The nucleoproteins, isolated according to the method of Hammarsten, were found to be more active than the whole extract.
Contrary to the genuine extract the solution of the nucleoproteins passes readily through a Berkefeld filter maintaining its full activity. The solution is rendered inactive by heating to 5°C for 15 min., likewise after a short digestion with trypsin or pepsin. It is more resistant towards acids than towards alkali. The activity of the solutions is maintained after dialysis. The activity seem to be linked to a protein. A purification could not be obtained by the high‐speed centrifuging.
The ratio P/N of the nucleoproteins is rather low, about 12 per cent. The active substances contain thymonucleic acid as well as ribosenucleotides. Neither the nucleic acids nor the protein compound alone were active. Finally reprecipitations of the nucleoproteins led to inactive products, whereby proteins are denatured. The characteristics of various fractions are described.
The chemical analysis of the products, whether active or inactive, have so far given no directive facts for further purifications. The activity of the substances depend probably on the intactness of an extremely labile component system, a special phosphoprotein or a nucleoprotein.
The active substance did not show any dipeptidase or polypeptidase activity. Nor was there any evidence of activity due to a cathepsin.
Die Wirkung Yon Carfoaminoylcholin und Ace‐tyl‐β‐Methylcholin auf Herzminutenvolumen und Atmung des gesunden Menschen.
Authors: GOLDBERG L. , LILJESTRAND G. 
Published: December 2008

Zusammenfassung.Bei drei Versuchspersonen wurde eine massige Zunahme des Herzminutenvolumens nach Zufuhr von Doryl beobachtet. Bei zwei Versuchspersonen ergab auoh Mecholyl Vergrosserung des Herzminutenvolumens.Sowohl Doryl wie Mecholyl fiihrten zu einer Erregung der Atmung, die sich in einer primaren Zunahme und sekundaren Abnahme des respiratorischen Quotienten zeigte.
Die Einwirkung von Blutdrucksänderungen im Carotissinus auf die Atmung bei der Katze
Authors: H. BJURSTEDT  , HESSER. C. M. 
Published: December 2008

Zusammenfassung.Mit Hilfe der beschriebenen Versuchsanordnungen sind die folgenden Beobachtungen an Atmungsreflexen bei endosinualen Druckvariationen bei der Katze gemacht worden:

Endosinuale Druckänderungen brauchen keinerlei Veränderung der Atmung herbeizuführen, selbst wenn typische Blutdrucksreflexe auftreten.
Unter gewissen Bedingungen können endosinuale Druckänderungen Atmungsvariationen herbeiführen, auch wenn keine Blutdrucksreflexe auslösbar sind.
Die obengenannten Versuchsergebnisse liefern keine Stütze für die Annahme, dass Atmungsreaktionen bei endosinualen Druckänderungen bei der Katze über die Barorezeptoren unter normalen Bedingungen erfolgen, sondern stehen vielmehr im Einklang mit der Auffassung, dass die Atmungsveränderungen über die Chemorezeptoren ausgelöst werden.
The Distribution of the Blood between the Lower Extremities and the Rest of Body
Authors: ASMUSSEN ERLING 
Published: December 2008

Summary.The amount of blood present in the legs under different conditions of work and rest is determined by means of the CO‐method on two subjects. During rest in the horizontal position it was 12 and 15 pCt of the total blood volume. On tilting the subjects 60° to a head‐up position it increased to 22 and 19 pCt, and on tilting the subjects 60° to a head‐down position it was 13 and 11 pCt, respectively. In free standing it was 17 and 15 pCt of the total blood volume. During work (410 and 820 mkg/min.) it was but slightly changed (17 and 11 pCt in one subject, 17 and 18 the other subject) whereas after work it was markedly increased in both subjects (to 26 pCt and 25 pCt).
Die Wirkung von Pervitin auf den Kreislauf und die Atmung beim Menschen.
Authors: BERSÉUS S. 
Published: December 2008

Summary.In 11 Versuchen an 7 gesunden Versuchspersonen wurde die Wirkung von Pervitin auf Kreislauf und Atmung untersucht. Pervitin wurde in intrainuskulärer Injektion in einer Dosis von 15 mg. per 70 kg. Körpergewicht gegeben. Das Herzminutenvolumen wurde mittels der Acetylenmethode von GROLLMAN bestimrnt.Eine halbe Stunde nach der Injektion wurde eine Steigerung des Herzminutenvolumens von 39 % des Normalwertes festgestellt, die nach 1 und l½ Stunde immer noch etwa 20 % ausmachte. Der Sauerstoffverbrauch stieg mässig. Die Ventilation und der respiratorische Quotient wurden in den meisten Fällen nicht beeinflusst, aber zwei der Versuchspersonen reagierten mit einer kräftigen Hyperventilation und einer Steigerung des Quotienten bis über 1.
The Excitability of the Respiratory Centre daring Sleep and during Evipan Anaesthesia.
Authors: ØSTERGAARD TORSTEN 
Published: December 2008

Summary.Determinations are described of the excitability of the respiratory centre during a waking state during spontaneous sleep and evipan sleep and during evipan anaesthesia by studying the reactions to the breathing of CO2 mixtures (Lindhard 1933).2 experiments with spontaneous sleep show in both cases reduced excitability in the respiratory centre during sleep. 3 experiments with sleep after giving of evipan in hypnotic doses show a larger reduction in the excitability which is solely due to deeper sleep, as it can be proved, that the evipan in hypnotic doses does not affect the centre depressively. From this the conclusion is drawn, that the reduction in excitability during sleep increases in proportion to the depth of the sleep.Finally 8 experiments with evipan anaesthesia show that the excitability of the respiratory centre, even during light anaesthesia, is affected far more in a depressive direction than during sleep. The results of the experiments further show thak this depression is increasing with the depth of the anaesthesia — i.e. with the concentration of evipan in the blood. At a certain concentration ‐ as a rule this occurs by a sudden overdosing ‐ the centre as the first of the vital ones will be put out of function, and the respiration paralysed.During sleep ventilation was decreased 20–38 %, during anaesthesia falls of 48–80 % appeared. While during deep the percentage fall occasionally was about the same with atmospheric and CO2 breathing, a proportionally larger fall was caused by CO2 during anaesthesia.The tension of carbon dioxide in alveolar air rose during sleep 3–6 mm, during anaesthesia up to 8–9 mm. The fall in ventilation during sleep was first and foremost due to a reduction in frequency, during anaesthesia on the other hand both to reduction in frequency and in depth of respiration.
The Localization of Rlineral Salts in Striated Muscle‐Fibres.
Authors: ENGSTRÖM ARNE 
Published: December 2008

Summary.Comparative ultraviolet and micro‐incineration studies of striated muscles have been made by the author. In order to obtain a distinct correlation between ultraviolet absorption and ash content, a material was used in which the muscle partitions are of considerable height (the leg muscles from Drosophila funebris and the subcutaneous muscles from larvae of Chironomus Thummi). One and the same section was used for ultraviolet microphoto‐graphy (wave‐length 2570 Å) and microincineration, which made it possible to obtain an exact localization of the ash. The result of the comparison was the finding that ash was regularly yielded by the intensely absorbing isotropic segments, which, on absorption measurement, were found to contain nucleotides (adenylic acids), whereas the anisotropic, weakly absorbing segments were practically devoid of ash. On account of these experimental findings it seems probable that the major part of the phosphagene is situated in the isotropic segments.
Studies on Nucleic Acid Metabolism in Plasma Cells
Authors: BING JENS , FAGRÆUS ASTRID , THORELL BO 
Published: December 2008

Summary.In order to study the endocellular formation of antibodies, plasma cells produced by injection of polyvalent pneumococcal vaccine or horse serum in rabbits, have been analysed with microspectrographical and microchemical methods. The successive examination of plasma cells after the injection showed that during the first stage of immunization the most frequently occuring type of plasma cell in cytochemical organization corresponds to the rapidly growing blood stemcell. During the latter stage of the immunization, with the constantly high titre level, a type of cell, identical with the mature plasma cell predominated. The transition from the rapidly growing cell to the mature cell is similar to the maturation of the blood‐cell, but with the difference that the ribose‐polynucleotide concentration in the cytoplasm remains unchanged. Together with the immunological data, this seems to indicate, that the formation of antibody protein proceeds essentially in a similar way as the protein synthesis in cells in general, namely in the presence of nucleic acids.
Further Investigations on the Effect of Adenosine Triphosphate and Related Phosphorus Compounds on Isolated Striated Muscle Fibres
Authors: BUCHTHAL FRITZ , DEUTSCH ADAM , KNAPPEIS G. G. 
Published: December 2008

Summary.

In agreement with previous results it was found that ATP prepared in different ways initiates contraction and changes birefrigence when applied in minute amounts to isolated striated muscle fibres of the frog. ATP is evenly distributed in the muscle and not localized specially in the region of the motor end plate.
Lack or excess of calcium just as excess of magnesium increase the threshold value for ATP.
While adenosine alone is without effect, it changes the contracture‐like effect of pyrophospate to a normal tetanus‐like contraction.
Inosine triphosphate, thrice as active as ATP in initiating contraction is without effect on birefringence.
Creatine phosphate has no effect on striated muscle, thus establishing the breakdown of ATP as the reaction nearest in time to contraction. Creatine phosphate + adenylic acid can replace ATP in the release of contraction and causes a reversible fall in birefringence. The time of restitution, however, is considerably longer than with ATP.
Acetyl phosphate is without effect.
Acetylcholine abolishes the effect of ATP on birefringence while it does not affect release of contraction. In denervated muscle previous application of acetylcholine prevents release of contraction by ATP. Contraction in denervated muscle is not accompanied by the slow changes in birefringence.
Intestinal Pain: An Electrophysiological Investigation on Mesenteric Nerves
Authors: GERNANDT B. , ZOTTERMAN Y. 
Published: December 2008

Summary.Afferent impulses from the abdominal viscera have been recorded from the splanchnic nerve and from fine strands of mesenteric nerves of the cat. The Pacinian corpuscles of the exposed mesentery were found to be extremely sensitive to the most gentle pressure, such as faint puff of air.The small intestine very rarely receives any large medullated fibres, and light mechanical stimuli such as slight pressure or touch do not give rise to any inflow of impulses. Fast impulses can be elicited only from those parts of the mesentery possessing Pacinian corpuscles.Injurious stimuli such as pinching applied to the intestinal wall as well as to the mesentery produce δ‐ and C‐potentials. In addition to this, intense stimulation gives rise to large potentials waves apparently built up by slow C‐potentials.It is thus concluded that nociceptive reactions from the intestine are not produced by afferent fibers belonging to the α‐or β‐group but by δ‐ and C‐fibers only.Support is given for the view that the intestinal wall is supplied by afferent fibers able to produce nociceptive reactions in response to such mechanical stimuli which if applied to the skin, would elicit nociceptive reflexes. The sensibility of the intestine itself is thus to be looked upon as very much the same as that of the skin deprived of its fast‐conducting afferent fibers, which respond to vibratory and light mechanical stimuli as well as to stronger pressure.
Some Perfusion Experiments on Horse's Brain.
Authors: ASTRUP P. , STEENSHOLT G. , WAMBERG K. 
Published: December 2008

Summary.The paper gives a report on some perfusion experiments on horse's brain. Results are given for the consumption of oxygen and glucose and for the respiratory quotient. Some anomalies and technical difficulties encountered in the experiments are briefly discussed.The authors are glad to express their thanks to P. Carl Petersens Fond, for generous financial support of our work. We are likewise greatly indebted to Dr. E. Jorpes, Stockholm, and to Løvens Kemiske Fabrik, Copenhagen, for valuable gifts of heparin.
On the Correlation between Hyaluronidase Content, and Spermiogenesis in the Testes
Authors: KULONEN EINO 
Published: December 2008

Summary.Investigations on the relation between morphological factors and the presence of hyaluronidase in bull testes are described. A very close correlation has been found to exist between the activity of the spermiogenesis and the hyaluronidase content. It would seem, however, that complete spermiogenesis is not required for the production of hyaluronidase. Thus the presence of hyaluronidase probably is a condition for fertility, but its occurrence is not per se an indication of the capacity to fertilize.The size and the dry substance content of the testis possess a certain correlation with the hyaluronidase content.The formation of hyaluronidase in cells in general is discussed.
The Sympathetic Vasomotor Innervation of the Skin of the Dog
Authors: FOLKOW BJÖRN , FROST JØRGEN , HÆGER KNUT , UVNÄS BÖRJE 
Published: December 2008

Summary.No evidence was found for the existence of a sympathetic vasodilator innervation to the skin of the hind limbs or the ear of the dog.Nor‐adrenaline has a pronounced vasoconstrictor action on cutaneous vessels. The observation agrees with the idea that the substance might be the transmitter at vasoconstrictor nerve endings.Adrenaline has a pure vasoconstrictor action on cutaneous vessels, even in low concentrations.Acetylcholine has a pronounced vasodilator action on cutaneous vessels. Thus it cannot be excluded as a possible transmitter at cutaneous vasodilator nerve enclings.
Intravascular Pressure as a Factor Regulating the Tone of the Small Vessels.1
Authors: FOLKOW BJÖRN 
Published: December 2008

Summary.Observations are described which indicate that the permanent stretching of the vascular smooth muscles, effected by the blood pressure, constitutes a stimulus which elicits increased tone in the small blood vessels. Reduction, respectively elimination of this stimulus is thought to be a major factor in the vasodilatation oc‐curing in the first stage of reactive hyperaemia.
Experiments on the Oxydation of Propyl Alcohol in Rabbits
Authors: ØRSKOV SØREN L. 
Published: December 2008

Summary.It is shown that injection of propyl alcohol gives rise to the formation of acid, which is ethersoluble, volatile and is extracted by toluene at the same rate as propionic acid, so that it is made very probable that this acid is formed.At the same time the concentration of another ethersoluble but not toluenesoluble acid increases. Probably it is an accumulation of lactic acid. Propionic acid seems to be formed and eliminated at a constant rate partly independent of the concentration of propyl alcohol.
The Effect of Acute Hypoxia on the Motor Cells of the Spinal Cord
Authors: KROGH ERIK 
Published: December 2008

Summary.The main problems of this study were:

Which nerve cells are responsible for the hyperactivity that occurs in the muscles of the lower extremities after hypoxia of the lower part of the medulla?
Which cytological changes or signs of degeneration can be found in these cells?

It was tried to elucidate the problem by correlating the clinical cytological and electromyographical findings in rabbits with experimentally introduced anoxia in the lumbar marrow.54 rabbits were used as experimental animals. The aorta was compressed by means of HAGGQVIST'S clamp for varying periods of time. The spasticity was examined electromyographically. EINAKSON'S specific staining method (gallocyanin‐chromalum) was used for the histological preparations. By means of this method a fairly accurate estimation of the nucleic acid content of the nerve cells can be obtained.The results showed a good agreement between the histological findings and the clinical and electromyographical picture.
Die Wirkung der Sympnthomimetica und Dihydroergotnmin auf Dnphnien
Authors: FLÜCKIGCER EDW. 
Published: December 2008

Zusammenfassung.

Es werden einige Beobachtungen iiber den Sauerstoffverbrauch der in den nachfolgenden Versuchen verwendeten reinen Linie von D. magna Straus mitgeteilt
1‐Adrenalin, d‐Adrenalin und 1‐Noradrenalin erhohen den Sauerstoffverbrauch; die Beziehung Konzentration‐Wirkung ist logarithmisch. 1‐Adrenalin und d‐Adrenalin unterscheiden sich fast nicht in der Wirkung, 1‐Noradrenalin ist nur etwa 3 ma1 weniger wirksam als 1‐Adrenalin
p‐Oxyphenyl‐aethanolmethylamintartrat (Sympatol) bewirkt eine maximal 20 % Steigerung dea 02,‐Verbrauchs, welche wahrscheinlich durch die allgemeine Aktivitatssteigerung der Tiere zustande kommt. Bei 1‐Ephedrin liegen wahrscheinlich ahnliche Verhaltnisse vor
Dihydroergotamin‐methansulphonat vermindert den Sauerstoffverbrauch der Daphnien nicht und bewirkt auch keine Verminderung der Stoffwechselwirkung von Adrenalin
1(+)Milchsaure steigert den Sauerstoffverbrauch, aber erst bei etwa 10 ma1 hoheren Konzentrationen als 1‐Adrenalin
Karbaminoyl‐cholinchlorid, ein Parasympathomimeticum, steigert den Sauerstoffverbrauch in ahnlichem Ausmass wie 1‐Adrenalin
Rabbit Red Cell Haemolysing Property of Human Plasma
Authors: HIRSJÄRVI EVA 
Published: December 2008

Summary.The rabbit red cell haemolysing property of human plasma was investigated in vivo and in vitro. Human plasma caused. in most cases, a decrease in the red cell count of rabbit blood in vitro as well as in vivo, though the reaction was stronger in vivo. Repeated injections of human plasma into rabbits decreased the susceptibility for haeniolvsis in vivo in vitro. Incubation with rabbit cells diminished the activity of human plasma to haemolyse rabbit cells in vitro.
The Effect of Certain Choline Esters on the Chemoceptor Activity in the Carotid Body
Authors: LILJESTRAND G. , ZOTTERMAN. Y. 
Published: December 2008

Summary.Minute amounts of a number of choline esters, injected into the carotid artery, elicited increased chemoceptor activity of the sinus nerve. The effect was especially pronounced for acetyl‐, acetylthio‐ and butyrylthiocholine; propionyl‐ and butyrylcholine were slightly less active, whereas for benzoyl‐, acetyl‐β‐methyl‐and succinyl‐choline somewhat larger doses were required.After local treatment of the carotid body with the anticholinesterase mintacol the responses to acetyl‐, propionyl‐, butyryl‐and benzoyl‐choline were greatly increased, but the sensitivity to the thiocholines was lowered. Oxygen lack led to a stronger stimulation after mintacol than before.DFP, applied locally, also led to a sensitization of the cheinoceptors to acetyl‐, butyryl‐, propionyl‐ and benzoylcholine as well as for oxygen lack. Acetylcholine was again an exception.The results support the view that acetylcholine or related substances are involved in the initiation of the chemoceptive discharge from the carotid body.