ISSN:0001-6772    

DOI:10.1111/j.1748-1716.1947.tb00465.x

出版商:Blackwell Publishing Ltd    

年代:1947

数据来源: WILEY

摘要:

Summary.The influence of drugs on retina1 rivalry between a horizontal and a vertical bar was studied with the aim of finding pharmaco‐logical agents which might become useful in the treatment of suppression and amblyopia in squint,Amytal, bromural, chloral, ethyl alcohol, phenobarbital and trional can weaken or abolish retinal rivalry. Under the influence of these drugs, completely simultaneous perception of the two dis‐parate objects may occur. I n less pronounced cases only a decrease in depth of suppression of the momentarily subjugated image is observed. Together with the decrease in intensity of rivalry the drugs cause a decrease in the frequency of alternation. If, in the normal state, there is an imbalance between the two competing pictures, one of them being dominant more than half of the time, the degree of imbalance usually increases when rivalry is weakened under the influence of the drugs.Morphine in one case caused a marked increase, in two other cases uncertain decreases in rivalry. 3‐methyl‐5.5‐diphenyl‐hydan‐toin (one case) had no effe

ISSN:0001-6772    

DOI:10.1111/j.1748-1716.1947.tb00466.x

出版商:Blackwell Publishing Ltd    

年代:1947

数据来源: WILEY

摘要:

Summary.The aim of this investigation has been t o study the variation of the intermediate oxidative metabolism during insect metab‐olism as reflected in the activity of the dehydrogenase systems. Pupae and praepupoe of %he fly Calliphora erythrocephala Meig, were used and proved to be excellent experimental material for this purpose.The gas metabolism, oxygen consumption, and carbondioxide production, determined by means of the Thunberg‐microspirometer, described a U‐shaped curve during metamor‐phosis. It was shown by the application of Thunbergs' methylene blue method that the experimental animals were carriers of hydro‐gen‐activating enzyme systems. Variations in the hydrogen‐activating capacity of the dehydrogenase systems or their spon‐taneous activity are likewise U‐shaped and of the same order of magnitude as that of the gas metabolism. For this reason i t is assumed that the U‐shaped course of the respiration is, t o a cer‐tain degree, connected with variations in the activity of the de‐hydrogenase systems. There is, however, no absolute agreement between the variations in the gas metabolism and the dehydro‐genase activity. Variations in pH in the serum also give a U‐shaped curve.About 30 organic compounds have been found capable of in‐creasing the hydrogen‐activating capacity of the experimental animals in vitro. There is reason to assume that corresponding dehydrogenases are active during metamorphosis. Also inhibiting substances are observed.Changes in the hydrogen‐activating capacity due t o the ef‐fect of 16 different substances have been followed during the entire metamorphosis. The results obtained show systematic, periodically occurring variations in activity, which are considered an indication of the change in the potential activity of the respec‐tive dehydrogenase systems.The fluctuations in the potential activity seem to occur at definite time intervals and for this reason it is thought that they represent generally critical periods in the intermediary oxidative metabolism during metamorphosis.The changes in the activity of the succino dehydrogenase has been studied during the entire metamorphosis, as well as the inhibitory effect of malonate and the influence of succinate on the spontaneous activity during the same period. The results obtained give reason to assume the existence of a “succinic cycle” during the period of mi

ISSN:0001-6772    

DOI:10.1111/j.1748-1716.1947.tb00467.x

出版商:Blackwell Publishing Ltd    

年代:1947

数据来源: WILEY

摘要:

Summary.It is found that the copper complex forming compound sodium diethyl‐dithio carbamate has no, or only an extremely small effect on cytochrome oxidase activity. The interpretation of this result and its bearing on previous work are briefly discusse

ISSN:0001-6772    

DOI:10.1111/j.1748-1716.1947.tb00468.x

出版商:Blackwell Publishing Ltd    

年代:1947

数据来源: WILEY

摘要:

Summary.By means of the colorimetric method of MCCARTHY and SULLI‐VAN for the determination of methionine in biological mixtures, an investigation is made of the methylation of ethanol arnine, dimethyl ethanol amine, glycocyamine and homocysteine. The results extend and corroborate those of previous investigation

ISSN:0001-6772    

DOI:10.1111/j.1748-1716.1947.tb00469.x

出版商:Blackwell Publishing Ltd    

年代:1947

数据来源: WILEY

摘要:

Summary.A brief review is given of certain current ideas on the rble of glycollic acid as a methylating agent. Next the results are reported of some in vitro experiments in which guanidine acetic acid and glycollic acid or glycine, and some other substances as well, wereincubated with suspensions of various animal tissues. The de‐terminations of creatine in the reaction mixtures were carried out both by the picric acid and by the dinitro‐benzoate methods. The results were negative: in no case could any trace of a creatine synthesis be demonstrated. Finally some perfusion experiments on the excised rabbit's heart were carried out. The results were in substantial agreement with the in vitro experiments. We may therefore be justified in concluding that glycollic acid is incapable of methylating guanidine acetic acid to creatine. The relation of these results to some previous investigations by other workers is discus

ISSN:0001-6772    

DOI:10.1111/j.1748-1716.1947.tb00470.x

出版商:Blackwell Publishing Ltd    

年代:1947

数据来源: WILEY

摘要:

Summary.The paper reports the results of an investigation of the enzyme in rabbit's liver that catalyzes the oxidation of mescaline. Another substrate for this enzyme is found. By inhibition experiments it is shown that the enzyme is in all probability structurally different from the mono amine oxidase. The experiments indicate that copper, iron, manganese and magnesium are probably of no importance for the enzymatic process. The r61e of metals is further discussed, and i t is shown that a suggestion about the nature of the mescaline oxidizing enzyme put forward by BERN‐HEIM and BERNHEIM is probably untenabl

ISSN:0001-6772    

DOI:10.1111/j.1748-1716.1947.tb00471.x

出版商:Blackwell Publishing Ltd    

年代:1947

数据来源: WILEY

摘要:

Summary.The elicitation of viscero‐motor reflex especially from the small intestine has been studied on the cat under light barbituric anesthesia or after decapitation.On animals with good reflex irritability, the reflex can be elicited from the intestinal wall by mechanical, electrical, chemical and thermal stimuli without the involvement of the mesentery or of its connection with the intestine.The effect of a stimulation of the intestinal wall is stronger the nearer the stimulus is placed to the mesenterial connection. This is explained by the fact that the densityof the nerve fibres must be greater here.A cutano‐motor reflex is much stronger than a viscero‐motor reflex elicited by the same stimulus on an equal area of skin resp. intestinal wall.No basis has appeared for the assumption that the intestinal wall should be supplied with pain nerve end‐organs, especially adapted for stretching or pulling, or which in any way should differ from the pain nerve end‐organs in the somatic innervated tissues. The principle difference between the visceral and somatic innervated organs probably is a quantitative, the density of riociceptive nerve fibres with e

ISSN:0001-6772    

DOI:10.1111/j.1748-1716.1947.tb00472.x

出版商:Blackwell Publishing Ltd    

年代:1947

数据来源: WILEY

摘要:

Summary.Experiments were performed in which the increase in rectal temperature was measured during ergometer exercise with the arms and with the legs.It was found that at a given output of energy, and at a given production of heat, the increase in temperature was larger with leg‐work than with arm‐work.Temperature measurements in the stomach showed that this difference was not due to the proximity during leg‐work of the working muscles to the measuring thermocouple.Experiments with leg‐work a t sea level and a t a simulated alti‐tude of 4,000 m showed no difference in the temperature increase, indicating that a more anaerobic condition and a more pronounced subjective feeling of strain have no effect on the thermoregulatingcentre during work.It is concluded that the different “setting” of the heat dissi‐pating centre during work with the arms and with the legs possibly is due to a different set of nervous impulses, efferent and reflex, reaching the centre during the tw

ISSN:0001-6772    

DOI:10.1111/j.1748-1716.1947.tb00473.x

出版商:Blackwell Publishing Ltd    

年代:1947

数据来源: WILEY

摘要:

Summary.Experiments have been performed on human sternal marrow kept alive in vitro in Locke's solution with and without the addi‐tion of different antipernicious anemia preparationsor of serum from either the same or from another person. These materials have been shown to maintain erythropoietic activity a t various levels.The slight formation of red cells which takes place in Locke's solution comes to a standstill after 8–10 hours, but is resumed later when red cells are hemolyzed and presumably liberate nutri‐tive materials. Folk acid (0.1 yo) will increase the formation of red cells considerably and liver extract even more so. “Foreign” serum has about the same effect, but the subject's own serum causes most rapid erythropoiesis, thus pointing to the existence of a factor peculiar to each individual. A number of pathological cases were, investigated. The “spontaneous” production of the red cells was diminished in untreated pernicious anemia and leukemia, but was normal in various other conditions studied. I n most of the cases, the pathological inarrow responded quite as a normal marrow does when liver of folk acid is added to the nutrient fluid. Only in lymphogranulomatosis benigna was a significant decrease decrease below normal found in the product:on of red cells when these materials were used. Tyrosine increased the effect of liver extract in untreated pernicious anemia and in leukemia but had no added effect, on normal bone‐marrow.The production of red cells from the pathological marrow nour‐ ished by normal serum is slightly decreased below normal in some of the pathological cases, especially in leukemia. I n this disease and in pernicious anemia there was a decreased total function of bone‐marrow plus “native” serum. All pathological marrows, however, were considerably activated by the addition of normal serum to the nutrient fluid. The use of pathological serum with normal marrow results in a significant decrease in red cell produc‐tion over that found when normal marrow is activated by “foreign” normal serum.In patients in whom a decrease was observed in the activity of the bone marrow cells and of the serum, i. e. in pernicious anemia, effective therapy resulted in an increase in the amount of those substances n both cells and serum which activate the formation of red blood cells in the marrow cultures.These results considered together with the results found in investigations of the ripening of the reticulocytes in vitro show that there are certain active principles in the serum, some being necessary for the production of red cells and some for the ripening of the reticulocytes. It appears that certain of these principles are necessary for both processes.I extend my deep gratitude to the Carlsberg Foundation and to the King Christian the Tenth Pund for sup

ISSN:0001-6772    

DOI:10.1111/j.1748-1716.1947.tb00474.x

出版商:Blackwell Publishing Ltd    

年代:1947

数据来源: WILEY