摘要:

Summary.The incorporation of P32into nucleotides, phosphoproteins and RNA from rat kidney has been investigated in normal and parathyroidectomized animals and the effect of parathyroid extract has been studied. The rats were killed 1.5 hours after the hormone injection and 1 hour after the parenteral administration of radioactive phosphate. The renal nucleotide pattern is characterized by a relatively high concentration of a substance which is most likely uridine diphosphate or a derivative of it. The parathyroid hormone seems to specially stimulate the incorporation of radiophosphate into this compound and into the phosphoproteins.

ISSN:0001-6772    

DOI:10.1111/j.1748-1716.1957.tb01403.x

出版商:Blackwell Publishing Ltd    

年代:1957

数据来源: WILEY

摘要:

Summary.Six healthy dogs and ten dogs with mastocytoma were studied. Of the latter, seven were treated with compound 48/80 intravenously. The blood pressure, plasma histamine and/or histamine content of the tumour was studied, and the results discussed in relation to the pertinent literature.

ISSN:0001-6772    

DOI:10.1111/j.1748-1716.1957.tb01404.x

出版商:Blackwell Publishing Ltd    

年代:1957

数据来源: WILEY

摘要:

Summary.The daily food intake has been measured in five pigeons while they were kept for 2‐4 weeks at ‐10° C, +18° C, and ‐24° C. At the end of each period the oxygen consumption was measured at various temperatures between ‐35° C and +20C. It was found that the food intake was closely correlated with the oxygen consumption, both of them indicating nearly the same critical temperature. Below this temperature both oxygen consumption and food intake increased linearly with the body‐to

ISSN:0001-6772    

DOI:10.1111/j.1748-1716.1957.tb01405.x

出版商:Blackwell Publishing Ltd    

年代:1957

数据来源: WILEY

摘要:

Summary.The sensitivity of the respiratory center to CO2during muscular work at normal and at low oxygen tensions has been studied in three human subjects.It was found that the rectilinear part of the stimulus‐response curves in normal air was displaced to the left of the resting curve and the more so the higher the work intensity. The steepness of the curves was in the majority of cases about the same. In low oxygen the stimulus‐response curves were displaced more to the left and were much steeper than for the same work intensity in normal air. The flattening of the stimulus‐response curves found at higher CO2concentrations is assumed to be due mainly to a special depressant effect of high CO2tensions on the respiratory c

ISSN:0001-6772    

DOI:10.1111/j.1748-1716.1957.tb01406.x

出版商:Blackwell Publishing Ltd    

年代:1957

数据来源: WILEY

摘要:

Summary.Standard ox heparin, dog mast cell tumour heparin, heparin monosulphuric acid and β‐heparin from ox lung were compared with respect to anticoagulant effect on human, bovine and dog plasma in one‐stage prothrombin, recalcification and thrombin systems, and on whole ox blood. Different values for the anti‐coagulant activity of a certain heparin was observed when using the various assay methods, which is in conformity with the results of previous authors. In addition it was demonstrated that one and the same assay method for a certain heparin may give different results depending on the species of plasma used as clotting sub

ISSN:0001-6772    

DOI:10.1111/j.1748-1716.1957.tb01407.x

出版商:Blackwell Publishing Ltd    

年代:1957

数据来源: WILEY

摘要:

Summary.Based upon works by Russian authors and upon own clearance studies the Hungarian authors Földiand Szabóin 1951 conclude that urea loading promotes tubular secretion of urea. In an attempt at reinvestigating the problem we made 18 clearance experiments in 5 dogs with altogether 87 clearance periods. Intravenous urea loads was performed in 14 experiments with 76 clearance periods. We never succeeded in raising urea clearance significantly above creatinine clearance. It is emphasized that true creatinine which shows the same values as inulin, not total chromogen determination has to be done for obtaining correct ratio

ISSN:0001-6772    

DOI:10.1111/j.1748-1716.1957.tb01408.x

出版商:Blackwell Publishing Ltd    

年代:1957

数据来源: WILEY

摘要:

Summary.1. The electroencephalogram (EEG) has been recorded in the cod (Gadus callarias) both in the awake state and under narcosis. The effects on the EEG of photic and acoustic stimulation have been observed.2. In the awake resting state, when the fish was in the dark, the dominating rhythm recorded was 8–13 c/sec. — especially from the optic lobes (fig. 3 B, fig. 4). When the fish was unsettled or in the light, the EEG was chiefly dominated by higher frequencies, 14‐32 c/sec. (fig. 3 A). Slow rhythms (less than 7 c/sec.) were most pronounced in the telencephalon and were relatively unaffected by surrounding circumstances.3. The arousal reaction, as it occurs in mammals,i. e.a substitution of the dominating 8‐13 c/sec. activity by a faster rhythm of lower amplitude, has been recorded in the cod EEG on sudden illumination of the fish (fig. 5). During acoustic stimulation no arousal reaction was recorded.4. Evoked potentials on photic and acoustic stimulation were recorded from the visual area of the mesencephalon and the acoustic area of the medulla oblongata respectively. On photic stimulation up to a stimulating frequency of 40 c/sec. and on acoustic stimulation up to 100‐140 c/sec., the evoked potentials followed each stimulus.5. It is concluded that the 8‐13 c/sec. activity in the cod corresponds to alpha rhythm of mammals and man, and that in the dorsal thalamus of cod there are parts that are homologous, as regards function, with the midline nuclei and intralaminar system

ISSN:0001-6772    

DOI:10.1111/j.1748-1716.1957.tb01409.x

出版商:Blackwell Publishing Ltd    

年代:1957

数据来源: WILEY

摘要:

Summary.A technique of catheterization of the renal arteries from a femoral artery in dogs and cats is described.The catheter did not influence the renal blood flow as measured on the venous side.The insertion of the catheter was not followed by any changes in the clearance of phenol red as measured for each kidney separately.We are greatly indebted to Miss Karen Nilsson for help with the photometry and to Mr. Olle Jönsson, who prepared the gold tubes

ISSN:0001-6772    

DOI:10.1111/j.1748-1716.1957.tb01410.x

出版商:Blackwell Publishing Ltd    

年代:1957

数据来源: WILEY

摘要:

Summary.By means of multielectrodes containing twelve leads along a 25 mm distance (Fig. 1) the spread of action potentials from a motor unit was studied over a cross section of the brachial biceps in man. The territory of the motor unit could be determined from the analysis of a single cross section of the muscle, since its fibres pass uninterrupted from tendon to tendon.The mutual position of two multielectrodes inserted perpendicularly to each other into the muscle was determined with an accuracy of 0.2 mm by recording with one multielectrode subthreshold pulses sent through successive leads of the other multielectrode (Fig. 2).The action potentials of a motor unit spread over an approximately circular area as evidenced by experiments in which the two multielectrodes traversed the centre of the motor unit (Fig. 4) and other experiments in which one of the multielectrodes was situated at the periphery of the motor unit (Fig. 5).Potentials with spike components exceeding 50 μV were confined to an average area four to six mm in diameter (Fig. 6 A). These potentials had a protracted terminal component of low amplitude and if they were recorded outside the site of innervation an initial positive component as well. Outside the area in which spike potentials occurred the potentials had a low amplitude, a short duration and a negative sign (Figs. 3, 4, 5).On account of volume conduction the action potentials were picked up in a larger area than occupied by the fibres of the motor unit. By means of the relationship between spike amplitude and distance from the potential source (Fig. 1 C) the average territory of the motor unit was determined to be four to six mm (minimum two and maximum ten mm) (Fig. 6 B). This area allows space for the fibres of ten overlapping motor units.On the same lead of the multielectrode action potentials from maximally six different motor units were recorded. Their potentials were often similar in shape so that they could be identified only by their discharge frequency (Fig. 9). The muscle fibres of as many as three of the intermingling motor units overlapped entirely (Fig. 8). The temporal dispersion of the spikes recorded on the different leads of the multielectrode was identical for these overlapping motor units (Fig. 7).The results are discussed with respect to their bearing on the parameters of the motor unit potential: The action potential of the motor unit arises from the summation of temporally dispersed potentials originating from fibre groups at a mutual distance of 0.3 to 1 mm. The amplitude of the motor unit potential is largely determined by the distance of the recording electrode from the fibre group closest to the electrode. The shape of the potential derives from the way in which the action potentials of two to three of these fibre groups summate. The duration of the potential is determined by the temporal dispersion of the component potentials due to the spatial dispersion of the end plates in the innervation zone

ISSN:0001-6772    

DOI:10.1111/j.1748-1716.1957.tb01411.x

出版商:Blackwell Publishing Ltd    

年代:1957

数据来源: WILEY