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991.
Polymorphonuclear leukocyte (PMN) migration was assessed in vitro using the agarose plate method in patients with psoriasis vulgaris, and compared with an age- and sex-matched control group. No significant difference was found between the two groups in the PMN response to the chemotactic substances F-Met-Leu-Phe (FMLP) or zymosan activated serum (ZAS). Equally, the chemokinetic or chemotactic potential of psoriatic serum did not differ from control serum. Our results do not support a primary abnormality of PMN function in psoriasis.  相似文献   
992.
The results of a national survey of trauma centers concerning their assessment and response to the problem of alcohol and trauma are reported. Surveys were returned from 154 trauma centers located in 43 states and the District of Columbia. The profile of the 125,000 patients treated at the centers is a 30-year-old man sustaining blunt trauma, usually in a vehicular crash. Two-thirds of centers estimated that the majority of their patients had abused alcohol. While acknowledging alcohol as a significant cause of trauma, only 55.2% of centers routinely obtain admitting blood alcohol levels. Less than a third of the centers employ alcoholism counselors. Most trauma centers are not providing services that allow them to fulfill their responsibility to detect and initiate treatment of alcohol abuse, a major cause of traumatic injury.  相似文献   
993.
The vascular endothelium plays an important and complex role in vascular allograft rejection. Antigens expressed by the endothelium can act to promote and be the target of rejection reactions, which often lead to thrombosis and ischemic necrosis of the allograft. In this study, segments of femoral artery and femoral vein with or without endothelium were grafted between allogenic or autologous control rats. Immunocompetent Lewis (RT1(1] recipient rats were randomly selected for groups (N = 14 for each) receiving the following: ACI- (RT1a) allografts with intact endothelium, allografts with endothelium removed before operation, autografts with endothelium, and autografts with endothelium removed. Rejection was assessed by graft patency as well as morphologic and ultrastructural changes. At 5 days, the allografts with intact endothelium were totally occluded, whereas allografts without endothelium remained patent, as did autologous control grafts with or without endothelium. Two additional groups (N = 14 each) receiving the de-endothelialized allografts or autografts were examined at 120 days after operation, revealing that grafts in both groups were still patent and had been re-endothelialized. These findings indicate that physical removal of vascular endothelium may depress vessel allograft rejection without immunosuppressive therapy.  相似文献   
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Since the role of cutaneous nerves in the pathogenesis of cutaneous diseases associated with diabetes mellitus is not well defined, cutaneous nerves in ten patients with severe diabetic neuropathy were electron microscopically investigated as a preliminary study. The specimens were taken from normal-appearing skin of their lower extremities. Cutaneous nerves were seen as axon-Schwann cell complexes in which variously degenerated axons and Schwann cells coexisted with normal ones. The degenerative changes were not, however, specific for diabetes mellitus.  相似文献   
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Changes in the height, weight, body mass index, triceps skinfold, and arm and estimated midarm muscle circumferences in lower socioeconomic Mexican American children, 6 through 17 years of age, from Brownsville, Texas, were documented on the basis of surveys done in 1972 and 1983. With the exception of height in youths ages 14-17, all parameters show gains at most ages, and in particular an increase in fatness. Brownsville Mexican American youth are similar in height, weight, and the body mass index to Mexican American youth in other areas of Texas. These trends confirm the large proportion of relatively short but heavy children among Mexican Americans.  相似文献   
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