摘要:

Summary.Complete generalized inhibition of individual retinal elements was observed in response to flickering light of increasing intensity in the darkadapted rabbit's eye. As soon as stimulus intensity had been lowered, the elements again began to respond to flicker.The inhibition was confined to frequencies of intermittent light above the ‘kink’ in the Ferry‐Porter curve. Within the upper part of this curve the energy required for inhibition gradually decreased with increase of flicker frequency.Lasting inhibition was only seen in the eyes that had been darkadapted for over 1½ hour. With shorter times of dark adaptation there was only a transient non‐flickering phase of the response to intermittent light depending upon duration of dark adaptation and flicker frequency. Immediate return of the flickering response was produced by light adaptation.Simultaneous determinations of energy necessary in each wave‐length for the excitatory or threshold fusion on one hand and the inhibitory fusion point on the other reveals two different sensitivity curves. Whereas the low‐energy curve for excitation practically agrees with the spectral distribution of sensitivity at the absolute threshold, the high‐energy curve for inhibition shows greatly increased sensitivity to blue light and humps occur in the green and the violet parts of the spectrum.The results would seem to be of some general interest also from the point of v

ISSN:0001-6772    

DOI:10.1111/j.1748-1716.1956.tb01319.x

出版商:Blackwell Publishing Ltd    

年代:1956

数据来源: WILEY

摘要:

Summary.In isolated mouse stomachs filled with Krebs solution to a pressure of 75 cm H., O and incubated in 37° C and 4.2 atm. oxygen pressure (technique of Davenport) no net transport of water takes place in spite of a fairly high acid secretion. In such preparations it was found by the simultaneous use of HDO and H2O13that the stomach wall is readily permeable to water. The permeability coefficients were 1.49‐105cm sec‐1for HDO and 1.91. 10‐5cm sec2for H2O18. The difference in the two figures is dependent on inherent physical differences in the two water molecules. It was thought that the normal volume secretion could be explained from these permeability figures and that the transportation of H+or Cl‐would exert sufficient osmotic forces for the normal water transport during s

ISSN:0001-6772    

DOI:10.1111/j.1748-1716.1956.tb01320.x

出版商:Blackwell Publishing Ltd    

年代:1956

数据来源: WILEY

摘要:

Summary.The effect of changes in oxygen tension upon the permeability of the placenta to d(+)xylose and sorbose was studied in situ. D(+)xylose or sorbose was injected into the foetal circulation and the fall in the foetal blood sugar was studied.It was observed that a maternal hypoxia or hyperoxia had no clearcut effect upon the placental transfer of these sugars.

ISSN:0001-6772    

DOI:10.1111/j.1748-1716.1956.tb01321.x

出版商:Blackwell Publishing Ltd    

年代:1956

数据来源: WILEY

摘要:

Summary.1. The plasminogen activator in pig heart tissue and pig lung tissue has been isolated in soluble form and partially purified.2. The tissue activator is a fairly thermostable substance especially at acid reaction.3. The tissue activator represents a type of plasminogen activator different from the activator found in urine or produced in blood, milk, and a number of other fluids in the organism.

ISSN:0001-6772    

DOI:10.1111/j.1748-1716.1956.tb01322.x

出版商:Blackwell Publishing Ltd    

年代:1956

数据来源: WILEY

摘要:

SummaryA closed circuit with a CO, filter, 95 % O2, (approximately) and minute CO concentrations were used for rebreathing experiments in a group of healthy individuals. The CO concentrations appearing in the system were attributable to either endogenous formation of CO or tobacco smoking. The CO concentration in the system was found t o vary with the position of the subject. Less CO accumulated in the system when the subject stood than when he sat or lay in the supine position.A hypothesis was proposed concerning the nature of the equilibrium between CO in the alveolar spaces and the COHb concentration of the blood.

ISSN:0001-6772    

DOI:10.1111/j.1748-1716.1956.tb01323.x

出版商:Blackwell Publishing Ltd    

年代:1956

数据来源: WILEY

摘要:

Summary.Intracisternal or intraventricular injections of small closes of highly purified Substance P elicit stimulation of respiratory frequency and amplitude in cats and rabbits.The effects on the blood pressure of injections of Substance P into the III:rd ventricle were usually small and variable.No consistent effects of moderately large doses administered intravenously were observed on the carotid occlusion test or on the effect of preganglionic stimulation on the nictitating membrane.Intraventricular injection of Substance P had no definite effect on diuresis.Substance P injected into a lateral ventricle caused a variety of symptoms of which a general inhibition of spontaneity was the most marked.

ISSN:0001-6772    

DOI:10.1111/j.1748-1716.1956.tb01324.x

出版商:Blackwell Publishing Ltd    

年代:1956

数据来源: WILEY

摘要:

Summary.A modification of the thiocholine method of Koelle (1951) has been used for the demonstration of the AChE activity in single nerve cells isolated from the surrounding tissue by means of microdissection technique.In neurons in the spinal, sympathetic and parasympathetic ganglions, as well as in the anterior and lateral horns of the spinal cord, large concentrations of AChE could be demonstrated inside the cytoplasm and neurite after a very short incubation time. By using this method the relative amount of such AChE bearing cells was found to be considerably higher than in previous investigations.

ISSN:0001-6772    

DOI:10.1111/j.1748-1716.1956.tb01325.x

出版商:Blackwell Publishing Ltd    

年代:1956

数据来源: WILEY