摘要:

Summary.1. A unit for prothrombin (P. T. U.) is defined as the amount of prothrombin which by total activation yields one unit of thrombin.2. Prothrombin is prepared from ox plasma. It seems to be a protein of globulin character.3. The transformation of prothrombin into thrombin seems to be a conversion of a globulin into an albumin.

ISSN:0001-6772    

DOI:10.1111/j.1748-1716.1943.tb02036.x

出版商:Blackwell Publishing Ltd    

年代:1943

数据来源: WILEY

摘要:

Summary.An investigation is made of the hydrolysis by liver esterase of the ethyl esters of fumaric and maleic acid, and of oleic and elaidic acid. It is found that in the former case the reaction velocity is considerably higher for ethyl fumar ate than for ethyl maleate. In the latter case no appreciable difference in reaction velocity is found. The possible interpretation of the phenomenon is briefly discussed.

ISSN:0001-6772    

DOI:10.1111/j.1748-1716.1943.tb02037.x

出版商:Blackwell Publishing Ltd    

年代:1943

数据来源: WILEY

摘要:

Summary.Micro‐electrode, amplifier and cathode ray oscillograph have been used for the recording of “spikes” from restricted units in the retina of anaesthetized snakes in response to monochromatic light of known energy content. The problem has been to study the distribution of sensitivity to monochromatic light of more or less restricted discharges in this cone eye.There is a broad dominator band of sensitivity with maximum in 0.560 μ, similar to the dominator found in the frog's eye.There are further two narrow modulator bands of sensitivity with maxima in respectively 0.600 and 0.520 μ.The “red” modulator is sometimes obtained in the practically isolated state but generally the “green” modulator appears coupled to it so that a secondary hump of variable size is found with max

ISSN:0001-6772    

DOI:10.1111/j.1748-1716.1943.tb02038.x

出版商:Blackwell Publishing Ltd    

年代:1943

数据来源: WILEY

摘要:

Zusammenfassung.Frühere Untersuchungen haben ergeben, dass Leberextrakt und getrockneter Magen beim normalen Menschen eine langsamere Permeierung von Glukose durch die Membran der roten Blutkörperchen bedingen.Die vorliegenden Versuche haben ergeben, dass viele andere Präparate die gleiche Wirkung haben und gleichzeitig wurde in vielen Versuchen eine Verlangsamung der Permeierung von Thiobarnstoff beobachtet.Eine Wirkung wurde nach Eingabe folgender Stoffe gefunden: verschiedene Leberpräparate, Magenpräparate, Bierhefe und deren Extrakte, Fleischextrakt und Eisen und nach einer Reihe von Vitaminen: Vitamin C, Vitamin B1, Vitamin B2, Vitamin E, Weizenkeimöl, sowie ein wässriger Extrakt dieses Präparates, nach Nikotinsäureaniid und eine schwaehe Wirkung auch nach Lebertran.In Weizenkeimöl kann ein Stoff vorkommen, der eine schnellere Permeierung von Thiohrnstoff bedingt.Die wirksamen Bestandteile in diesen Stoffen wirken wahrscheinlich in kleinen Mengen. Ein Einfluss auf die Permeabilität wurde nach 25 mg Vitamin C, 1.25 mg Vitamin B1, 1.25 mg Vitamin B2, 1.5 mg Vitamin E, 50 mg Nikotinsäureamid und nach 1 mg wässrigem Extrakt von Weizenkeimöl beobachtet. In den meisten Fällen wurden geringere Dosen als die hier angeführten nicht untersucht.Eine Wirkung von Leberextrakt trat 6 Stunden nach der Eingabe auf.Die wirksamen Bestandteile in der Leber und in Hefe sind teilweise hitzeunbeständig und die Sicherheit dieser Beobachtung wird diskutiert.Es wird weiterhin erörtert, wie die Beeinflussung der Permeabilität der roten Blutkörperchen vorsichgeht und sowohl mit einer direkten als einer indirekten Wirkung gerechnet. Als Grundlage hierfür dienen bisher nicht veröffentlichte Beobachtungen über die Beeinflussung der Penneabilität der roten Blutkörperchen nach Zusatz der genannten Stoffe in vitro und einige Versuche mit Vitamin C Injektionen, die schnellere Permeierung von Glukose bedingten, d. h. eine umgekehrte Wirkung hatten wie nach peroraler Eingabe des Stoffes.andere Präparate hatten nach intramuskulärer Zufuhr die g

ISSN:0001-6772    

DOI:10.1111/j.1748-1716.1943.tb02039.x

出版商:Blackwell Publishing Ltd    

年代:1943

数据来源: WILEY

摘要:

Summary.The resistance to direct current (voltage 0–12 V) of a 7 cm2skin area on the volar side of the forearm has been determined under different conditions, using polarization‐free silver‐silver chloride electrodes.The skin resistance is almost exclusively located in the stratum corneum and decreases very markedly with increasing electrolyte content of this layer. The conductivity of the stratum germinativum corresponds to that of the internal tissue which is rich in electrolyte, and behaves like a low ohmic resistance to d. c.On 7 cm2of skin area, the stratum corneum shows polarity to d. c. at currents below 1 mA, since the resistance to anodic conduction increases with increasing e. m. f. up to 2–4 volts, while the resistance to cathodic conduction decreases. At voltages above 2–4 volts, the resistance to both directions of current decreases to a value which corresponds to the resistance of the internal tissue. This decrease in resistance is presumably due to a short‐circuiting of the stratum corneum. The polarity of the stratum corneum, which is highest when voltages around 2 volts are applied, is brought into relation to a possible electric charge of the stratum corneum and to the type and the concentration of the contact electrolyte.The pH of the contact electrolyte (4 cc I per cent KCl‐solution) decreased after standing on the skin for 20–45 min to a mean value of 4,97, determined on 4 persons in 14 experiments. In contradistinction to REIN'S investigations, no change in the pH of the contact electrolyte after anodic and cathodic conduction of d. c. through the skin co

ISSN:0001-6772    

DOI:10.1111/j.1748-1716.1943.tb02040.x

出版商:Blackwell Publishing Ltd    

年代:1943

数据来源: WILEY

摘要:

Summary.1) We have performed local leading off by means of ADRIAN and BRONK'S concentric needle electrode from the extensors of the forearm of rabbits during direct electric and chemical stimulation of the motor area of the cortex partly in the waking animal and partly under anaesthesia.2) By electrical stimulation of the cortical motor area agreement between the frequency of the muscle action potential and the frequency of the stimulation is only seen when the latter is below 10 cycles.3) In electrical as well as in chemical stimulation of the motor area of the cortex a pronounced after‐activity was found, often persisting for several minutes. This after‐activity is of central origin.4) The frequency of the muscle action potentials varies during electric and chemical stimulation of the cortex between 2–3 per second and c. 80–90 per second. During strychnine action a frequency of up to 125 per second was found.5) Quinine has an inhibitory effect on the muscle action potentials (the motor end‐plate) produced by the action of strychnine on the cortex. Calcium has no effect on the strychnine contractions.6) Picrotoxin acts much the same as strychnine on the motor area of the cortex, while cardiazol in a 10 % solution has only a very slight centr

ISSN:0001-6772    

DOI:10.1111/j.1748-1716.1943.tb02041.x

出版商:Blackwell Publishing Ltd    

年代:1943

数据来源: WILEY

摘要:

Summary.The amount of ripening substances in plasma is considerably reduced when whole blood is stored. The reduction seems to be larger, the more reticulocytes were found in the blood sample. When the blood clots about frac12; of the ripening substances disappear.When plasma is stored only a slight decrease in the quantity of ripening substances occurs. Plasma incubated for 24 hours at 4° remains practically unchanged.The quantity of ripening substances in the plasma of various mammals shows a certain correlation between the number of reticulocytes in the circulating blood and the concentration of the substances that determine the ripening of the reticulocytes, so that a high percentage of reticulocytes goes with a low ripening index and vice versa. This applies both from individual to individual and from species to species. In blood in which no reticulocytes are found there is the highest concentration of ripening substances. This being the case with oxen I chose to their plasma as the unit for the concentration of ripening substances

ISSN:0001-6772    

DOI:10.1111/j.1748-1716.1943.tb02042.x

出版商:Blackwell Publishing Ltd    

年代:1943

数据来源: WILEY

摘要:

Summary.The quantity of ripening substances in young rats is large at birth and afterwards decreases with the fall in the number of reticulocytes in percentage of erythrocytes, and when figure sare reached that accord with those found in mature rats, the rest of the blood picture also resembles that in mature rats.During chronic hemorrhagic anemia a rise in the number of reticulocytes may be seen in rabbits. The reticulocytes do not change in character as regards the time they take to ripen when they are subjected to the same concentration of ripening substances, but on the other hand an increase in the quantity of ripening substances in plasma is found in anemized rabbits. This increase shows that under the conditions here described the reticulocytes in the vascular system must ripen about 20 ‐ 30 % more rapidly than those in normal rabbits.In the two cases investigated an increased erythropoiesis then is followed by an increased amount of reticulocytes ripening substances in the plasm

ISSN:0001-6772    

DOI:10.1111/j.1748-1716.1943.tb02043.x

出版商:Blackwell Publishing Ltd    

年代:1943

数据来源: WILEY

摘要:

Summary.A convenient method for the preparation of renin from pig's kidney is described.Purification of crude renin preparations has been accomplished by fractionate precipitation with acetone or by adsorption to kaolin.A dialysable, heat‐stable pressor substance may appear spontaneously in dialyzed renin solutions. The new substance has not the properties of hypertensin (angiotonin

ISSN:0001-6772    

DOI:10.1111/j.1748-1716.1943.tb02044.x

出版商:Blackwell Publishing Ltd    

年代:1943

数据来源: WILEY

摘要:

Summary.A series of experiiiients on rabbits has shown that1) Ether anaesthesia does not alter the citric‐acid content of the blood serum (Ci/s) in a nephrectomized animal. just as little as it does in a normal animal;2) Ci‐elimination in a nephrectomized animal proceeds with the same intensity both before and after an ether anaesthesia;3) After nephrectomy without anaesthesia the Ci/s rises, as it also does after nephrectomy under anaesthesia;4) After nephrectomy without anaesthesia the elimination of administered Ci is considerably slowed up as compared with the elimination before the nephrectcmy.The experiments show that the anaesthesia administered in the Writer's earlier animal experiments did not influence the results of the investigation, which have accordingly been confir

ISSN:0001-6772    

DOI:10.1111/j.1748-1716.1943.tb02045.x

出版商:Blackwell Publishing Ltd    

年代:1943

数据来源: WILEY