Using metal‐filled micropipette electrodes we have recorded responses from single units in the optic tectum and optic chiasma of the goldfish. Responses were evoked by visual stimulation with spots of light and with black discs of various sizes. In many cases, after recording from a unit, the position of the electrode tip was marked by making an electrolytic lesion 10‐50 µ in diameter. The...... hiện toàn bộ
Lung irritant receptors in anaesthetized rabbits are stimulated by deflations and large inflations of the lungs, with irregular and rather rapidly adapting discharges. After deflation the spontaneous discharge of the receptors is increased, and dynamic compliance is decreased. After inflation the spontaneous discharge is decreased, and compliance is increased. The responses of the receptor...... hiện toàn bộ
1. A new technique has been developed for the preparation of a permanent parotid fistula in the sheep. The advantage over the Pavlov‐Glinski operation is that the saliva drips from the dependent point of a skin teat. The secretion rate may be unobtrusively observed without fixation of any apparatus to the animal. Thirty‐seven sheep with parotid fistulæ have been studied.2....... hiện toàn bộ
The results of the commonly accepted in vitro tests, made upon samples of stored blood, are fallacious indicators of the state of preservation of biological activity, as judged by the subsequent in vivo survival of the erythrocytes. In the selection of preservative solutions, however, in vitro tests may have a...... hiện toàn bộ
1. Observations made on dogs show that morphine sulphate administered during the course of a water diuresis is antidiuretic, whether it is given intravenously (0·08 mg./ kg.) to the unanæsthetized animal, or injected into the supraoptic nuclei (4‐32 ug.) under chloralose ancesthesia.2. After section of the supraoptic tracts the injection of morphine sulphate intravenously ...... hiện toàn bộ
Marjorie J. Dobson, W. Duane Brown, A. Dobson, A. T. Phillipson
1. The papillæ of the surface of the rumen of sheep have been shown to have a rich blood and lymphatic supply in intimate contact with the basal layer of the stratified squamous epithelium.2. The basal layer of the epithelium consists of columnar cells which in the papillary bodies are arranged round the capillaries, the long axis of the cells being perpendicular to the le...... hiện toàn bộ
1. The influence of large doses of cortisone on the mitotic activity which normally occurs after partial hepatectomy in mice was studied. At the same time the changes in liver protein, fat, glycogen and nucleic acids were followed.2. In the mice given cortisone, mitoses were rarely seen 2 days after operation, whereas at that time the mitotic rate in controls was very high...... hiện toàn bộ
In cats anæsthetized with chloralose it was found that below about 18° C. the rhythmic pattern of discharge in low‐threshold pulmonary stretch fibres is reversed in relation to the respiratory cycle. This reversed pattern is apparently responsible for the reversal of the Hering Breuer inflation reflex (Head's paradoxical reflex). Evidence favouring this is that reflex inhibition of respira...... hiện toàn bộ
An isolated kidney obtained from a donor dog was perfused at constant pressure with blood from the femoral artery of a recipient dog. The left atrial pressure of the recipient dog was increased by approximately 20 cm H20 by inflating a balloon in the left atrium. Left atrial distension caused an increase in urine flow and sodium excretion from the isolated perfused kid...... hiện toàn bộ
1. Evidence is produced that the vagus controls the secretion of the cardiac and pyloric mucous glands and the mucous neck cells of the fundal glands.2. A histological procedure is described for staining these cells selectively and intensely.3. No effect of vagal nerve stimulation on the surface epithelial cells of the stomach has been seen.... hiện toàn bộ
Các tạp chí khác
Tạp chí Khoa học Kiến trúc và Xây dựng
Tạp chí Khoa học - Công nghệ trong lĩnh vực An toàn thông tin