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排序方式: 共有666条查询结果,搜索用时 46 毫秒
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Zusammenfassung Die Vorteile der aufgeschobenen Spalthauttransplantation gegenüber der prim?ren Spalthautdeckung werden diskutiert, die Technik
und unsere Erfahrungen aus einj?hriger Anwendungszeit der Methode werden berichtet. Bei besonderen. F?llen erm?glicht die
Anwendung des Fibrinklebers ein gutes Ergebnis.
Summary The advantages of the delayed skin grafting compared with primary skin grafting are discussed, the technique and our experiences in this method having been used clinically for one year are reported. In special cases the results improve by the use of the fibrin adhesive system.相似文献
94.
G Mandl 《Vision research》1985,25(2):267-281
Are there visual cells in the cat superior colliculus, selectively sensitive to relative pattern movement? Based on extracellular recordings from paralyzed pretrigeminal preparations, a sample of 76 collicular units could be divided into two main types according to relative movement sensitivity: those that responded optimally and selectively to one specific relative velocity between a small disk and a full-field grating; and those that discharged maximally whenever the grating shifted relative to a disk moving at one specific “absolute” speed, regardless of the precise relative velocity between the two. It was hypothesized that the latter group, in conjunction with extraretinal “calibration” cues, may be part of a neural mechanism encoding spatial depth in terms of motion parallax. 相似文献
95.
Extracellular records from 54 single cells in cat optic tract (14), visual cortex (18) and superior colliculus (22), have shown that ventilation of acute animals with a 70%: 30% mixture of N2O/O2 can modify unit responses to visual stimuli. Results indicate that, under nitrous oxide, (a) responses to flashed or moving stimuli may be severely reduced, and frequently abolished. This may be accompanied by either a sharp decrease; or, conversely, by a dramatic increase, in the resting discharge rate; (b) the degree of directional preference of a given unit, in response to a moving visual stimulus, may be substantially modified; (c) the temporal distribution of unit firing may be modified. While about half (57%) of the units in the optic tract were affected by N2O, only 28% of cortical cells showed any N2O-related response modification. The largest effect was observed in the superior colliculus, where 86% of cells were influenced by the anaesthetic. It is suggested that these results might be explained by a selective interference of N2O with serotonergic transmitter mechanisms. 相似文献
96.
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Cigarette smoke impairs elastin resynthesis in lungs of hamsters with elastase-induced emphysema 总被引:2,自引:0,他引:2
M Osman J O Cantor S Roffman S Keller G M Turino I Mandl 《The American review of respiratory disease》1985,132(3):640-643
The severity of pulmonary emphysema can be affected by exposure to cigarette smoke in several ways. Inactivation of alpha-1-antitrypsin and recruitment of leukocytes to lung airways shifts the protease-antiprotease balance towards increased elastolytic activity. The present study demonstrates an additional effect of cigarette smoke inhalation and retardation of the repair process and of the neosynthesis of cross-linked elastin. Hamsters with elastase-induced emphysema, exposed to cigarette smoke for 1 wk immediately after elastase administration, showed a 40% reduction of 14C-lysine incorporation into the elastin-specific cross-links, desmosine, and isodesmosine. Concomitantly, there was a decrease in the level of lung lysyl oxidase to that observed in uninjured control animals, in sharp contrast to the sevenfold increase in lysyl oxidase activity in hamsters with elastase-induced emphysema recovering under atmospheric conditions. These findings suggest that impairment of the production of lysyl oxidase and the resynthesis of cross-linked elastin by smoke inhalation exacerbates alveolar destruction. 相似文献
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