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41.
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The effects of amphetamine on the extinction of intracranial self-stimulation (ICSS) and on postextinction ICSS performance were examined in rats implanted with electrodes either in medial prefrontal cortex (mPFC) or in the posterior hypothalamus-ventral tegmental area (PH-VTA). Lever-pressing for ICSS was allowed to stabilize in daily 15-minute sessions before each animal was exposed to 5 minutes of extinction (responding without reward). Animals were administered either 0.25 mg/kg d-amphetamine or saline before baseline, extinction and postextinction sessions. After amphetamine treatment, the number of lever presses during extinction was higher in mPFC animals and lower in PH-VTA animals compared with saline-treated controls. Rates did not change immediately after extinction but, one day later, rates had increased in all saline-treated animals (both PH-VTA and mPFC animals) and had decreased in all amphetamine-treated animals. These findings demonstrated that the effects of amphetamine on the extinction of ICSS were different in cortical and hypothalamic sites, possibly because of regional differences in stimulus-evoked reinforcement and inhibitory processes. 相似文献
43.
D. Bakish C. L. Hooper D. L. West C. Miller A. Blanchard F. Bashir 《Human psychopharmacology》1995,10(2):105-109
This retrospective study was undertaken with the objective of determining how effective and safe moclobemide, a specific and reversible inhibitor of monoamine oxidase-A (RIMA), is when used in combination with specific serotonin re-uptake inhibitors (SSRIs), in a clinical setting. A thorough chart review was done of all patients with affective and anxiety disorders seen at our centre who received combination treatment with moclobemide and an SSRI. Combination moclobemide-SSRI treatment demonstrated good efficacy in treating treatment-resistant patients. The combination treatment was well tolerated with very few drug interactions. Dosages should be started low, titrated slowly and carefully, and patients should be monitored closely. 相似文献
44.
The role of intestinal flora on the interactions between nonparenchymal cells and hepatocytes in coculture 总被引:2,自引:0,他引:2
T R Billiar M A Maddaus M A West D L Dunn R L Simmons 《The Journal of surgical research》1988,44(4):397-403
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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K West 《Histopathology》2004,44(3):296-296
47.
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
48.
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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