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81.
Endoscopic retrograde biliary drainage 总被引:1,自引:0,他引:1
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Kim WM; Merskey C; Deming QB; Adel HN; Wolinsky H; Clarkson TB; Lofland HB 《Blood》1976,47(2):275-286
Inbred Carworth Farms Nelson (CFN) congenitally hyperlipidemic rats had significantly shorter coagulation and prothrombin times and higher levels of coagulation factors, II, V, VII, VIII, and X than did controls. Conversely, congenitally hypolipidemic rats of the same strain had significantly longer coagulation and prothrombin times and lower levels of factors II, V, VII, X and XII and of blood platelets than did controls. A loop-shaped polyethylene cannula was inserted into the aorta to assess the potential for thrombosis. The hyperlipidemic group obstructed this significantly faster and the hypolipidemic group slower than did the controls. Normal CFN rats made hypertensive by unilateral renal artery clip developed hypertension together with significantly elevated serum cholesterol and factor VII and X levels. Rhesus monkeys with diet-induced hyperlipidemia showed shorter prothrombin times and higher factor X levels than did controls on normal diet. By selective breeding, two groups of squirrel monkeys were obtained. Both groups had similar serum cholesterol levels on a normal diet but one group (hyperresponders) showed higher serum cholesterol levels on a cholesterol-containing diet than did the other (hyporesponder) group. Both groups showed significantly elevated levels of factors II, V, VII, IX and X on a cholesterol-containing diet. There was good correlation between the levels of many coagulation factors and serum cholesterol in both rats and monkeys. If thrombosis is important in the genesis of atherosclerosis, these findings could indicate that elevation of plasma lipids may play a role, via the coagulation pathway, in the production of human vascular disease. 相似文献
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Maturo VG; Zusmer NR; Gilson AJ; Smoak WM; Janowitz WR; Bear BE; Goddard J; Dick DE 《Radiology》1980,137(2):457-463
Innovations in design of a dedicated breast scanner resulted in automation of the scanning process, the production of high resolution images of the whole breast and an efficient mode of image review. The results of clinical evaluation of the prototype of this breast scanner investigating normal breasts as well as benign and malignant breast lesions are presented. 相似文献
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Linda WM van Kerkhof Ruth Damsteegt Viviana Trezza Pieter Voorn Louk JMJ Vanderschuren 《Neuropsychopharmacology》2013,38(10):1899-1909
Social play behavior is a characteristic, vigorous form of social interaction in young mammals. It is highly rewarding and thought to be of major importance for social and cognitive development. The neural substrates of social play are incompletely understood, but there is evidence to support a role for the prefrontal cortex (PFC) and striatum in this behavior. Using pharmacological inactivation methods, ie, infusions of GABA receptor agonists (baclofen and muscimol; B&M) or the AMPA/kainate receptor antagonist 6,7-dinitroquinoxaline-2,3(1H,4H)-dione (DNQX), we investigated the involvement of several subregions of the medial PFC and striatum in social play. Inactivation of the prelimbic cortex, infralimbic cortex, and medial/ventral orbitofrontal cortex using B&M markedly reduced frequency and duration of social play behavior. Local administration of DNQX into the dorsomedial striatum increased the frequency and duration of social play, whereas infusion of B&M tended to have the same effect. Inactivation of the nucleus accumbens (NAcc) core using B&M increased duration but not frequency of social play, whereas B&M infusion into the NAcc shell did not influence social play behavior. Thus, functional integrity of the medial PFC is important for the expression of social play behavior. Glutamatergic inputs into the dorsomedial striatum exert an inhibitory influence on social play, and functional activity in the NAcc core acts to limit the length of playful interactions. These results highlight the importance of prefrontal and striatal circuits implicated in cognitive control, decision making, behavioral inhibition, and reward-associated processes in social play behavior. 相似文献