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51.
Kupffer cells are exposed directly to a number of factors in the portal circulation that can modify or regulate their responses to septic stimuli. The gut represents a potential source of a number of these factors including endotoxin, lymphokines, and prostaglandins. We examined Kupffer cells from germfree rats and germfree rats exposed to endotoxin or bacteria via their GI tracts to determine the importance of the intestinal flora in maintaining or modulating Kupffer cell responses. Kupffer cells from germfree animals were reduced in numbers and failed to respond to LPS in Kupffer cell: hepatocyte coculture. When germfree rats were exposed to bacterial endotoxin or bacteria via the gastrointestinal tract their Kupffer cells increased in numbers to normal and the cells responded to LPS in culture. Intestinal overgrowth with Escherichia coli for 2 days activated the Kupffer cells and significantly increased Kupffer cell sensitivity to LPS. These data suggest that the environment of the gastrointestinal tract is important for normal Kupffer cell responses and that intestinal bacterial overgrowth can modify Kupffer cell responses to septic stimuli.  相似文献   
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全身麻醉插管术后院内获得性肺部感染探讨   总被引:17,自引:3,他引:14  
全身麻醉气管插管术后下呼吸道感染具有较高发生率。分析526例手术时间超过4小时普外科病例,经u检验发现全身麻醉气管插管术后患者肺部感染率明显高于持续性硬膜外麻醉术后患者,影响因素主要与全麻插管用具及麻醉机消毒情况有关,也与术前存在慢性阻塞性肺部疾患和术后保留气管插管有关。降低全麻术后肺部感染应重视无菌操作,尽可能对麻醉机管道进行常规消毒。  相似文献   
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A double-blind, placebo controlled trial was undertaken to examine the effect of the 5-HT3 antagonist, ondansetron .25 mg bd on cigarette withdrawal symptoms and on proportion of individuals maintaining continuous abstinence for 4 weeks in a smoking treatment programme. A total of 111 smokers were allocated to active or placebo conditions and began taking their study medication 2 weeks before the quit date. They attended the smokers clinic for weekly group treatment sessions. The results showed no evidence for less severe withdrawal symptoms or improved abstinence rates in the active medication group. They suggest that inhibiting 5-HT3 activity is not an effective method of controlling nicotine withdrawal or helping smokers to stop.  相似文献   
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Are there any successful men from criminogenic backgrounds?   总被引:4,自引:0,他引:4  
In the Cambridge Study in Delinquent Development, a prospective longitudinal survey of 411 London males, a vulnerable group of 63 boys from criminogenic backgrounds was defined on the basis of the best nonbehavioral predictors of delinquency at age 8-10 (low family income, large family size, convicted parents, low intelligence, and poor parental child-rearing behavior). These males were followed up to age 32, and the more successful men were defined according to criteria such as the absence of convictions and of other deviant behavior, good relationships with wives and children, and good accommodation and employment histories. Hence, "success" here refers to satisfactory social adjustment. The more successful men were those who had been neurotic at age 10, those who had few or no friends at age 8, those without convicted parents or behavior problem siblings, those with mothers who had a high opinion of their sons, and those who did not spend their leisure time with their fathers. At age 8-10 they were already better behaved and less daring than those later judged as the unsuccessful men. There was some tendency for shyness to act as a protective factor against delinquency for non-aggressive boys but as an aggravating factor for aggressive boys.  相似文献   
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Ordinary plastic buttons may be used as bolster devices to relieve tension across wounds. This article describes the method of placement of those "button bolsters" and suggests two methods of closing the wound once they are in place. This simple technique is easily mastered and gives additional wound closure security in the initial phase of wound healing.  相似文献   
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