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The effect of ageing on adrenergic neurons was studied in the hypogastric ganglion of the male rat using the formaldehyde-induced fluorescence method. With age, two changes were obvious. Firstly, the fluorescence intensity of the neurons decreased throughout postnatal life and the number of completely non-fluorescent adrenergic neurons increased. Secondly, the amount of non-specific fluorescence due to lipofuscin pigment increased. The pigment fluorescence was also found around the neurons in satellite cells. 相似文献
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Fourteen-day-old, mouse-derived Schistosoma japonicum schistosomula survived, matured, and deposited viable eggs following surgical transfer to the hepatic portal system of rabbits. The survival of such schistosomula is essentially eliminated in rabbits immunized with either mouse erythrocytes or mouse gamma globulin. Sera from rabbits immunized with either mouse erthrocytes or mouse gamma globulin in the presence of normal leukocytes is lethal for mouse-derived schistosomula 14 days of age or older. These sera have no significant effect on newly transformed schistosomula or those derived from rabbits. It is suggested that these results give additional evidence that immunological enhancement is one of the mechanisms involved in parasite survival. 相似文献
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An electromyographic study of nonmimetic skeletal muscles was carried out in 8 normal adults and 4 patients with spastic hemiparesis during all stages of sleep for a total of 21 nights. All normal subjects showed absence of tonic electromyographic activity in all nonmimetic skeletal muscles in all stages of sleep. Also, during quiet, relaxed wakefulness, tonic muscle discharges disappeared in the normal subjects. Three patients with upper motor neuron spasticity demonstrated results during sleep similar to those obtained in the normal subjects. In the fourth patient, tonic muscle discharges persisted into stage 2 non-REM sleep, disappeared within 30 to 240 seconds following the onset of stage 2 sleep, and were absent during stages 3 and 4 sleep and REM sleep. 相似文献
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An analysis is made of 24 cases of primitive lithiasis of the biliary tracts, viz; 10 of diffuse intrahepatic lithiasis, 9 of intrahepatic lithiasis localized in one of the ducts; and 5 of extrahepatic lithiasis. The most common cause were stenosis (14 cases) generally of idiopathic or congenital nature, followed by those of iatrogenic or tumoral origin. There were also cases of isolated or diffuse anomalus dilatation of the biliary ducts. A lithogenetic bile as well as infectious processes are rather considered secondary factors. The diagnosis of the real nature of the condiction was usually established in the postoperative period, this being an explanation why repeated surgery was so common (75%). There was a high postoperative mortality in the diffuse forms owing to severe manifestations of biliary sepsis perpetuated by the stones. Depending upon the individual cases the following procedures are proposed: 1) Biliodigestive anastomosis 2) Sphinteropapilloplasty 3) Dilatation and calibration of the stenosis 4) Postoperative instrumental extraction of calculi. The last-named procedure was carried out in 58% of the cases and result in an improvement in the serious prognosis. Primitive lithiasis should always be borne in mind when undertaking surgery of the biliary tracts in order to avoid additional surgery. 相似文献
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It is established that the adsorption of gases and vapours on the surface of thin gallium films causes an increase or decrease in the resistance depending on the structure of the film. The resistance of a film which is comparatively homogeneous in thickness does not change during adsorption. In other cases the observed effects are either due to diminution of the thickness of the metal bridges between metal grains or are related to the emission mechanism of the conductivity. It is impossible to draw any conclusions about the nature of the chemisorption bond from the effects of adsorption on the cinductivity of thin metal films. 相似文献