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991.
992.
Surprisingly little is known regarding the human mixing patterns relevant to the spread of close-contact infections, such as measles, influenza and meningococcal disease. This study aims to estimate the number of partnerships that individuals make, their stability and the degree to which mixing is assortative with respect to age. We defined four levels of putative at-risk events from casual (physical contact without conversation) to intimate (contact of a sexual nature), and asked university student volunteers to record details on those they contacted at these levels on three separate days. We found that intimate contacts are stable over short time periods whereas there was no evidence of repeat casual contacts with the same individuals. The contacts were increasingly assortative as intimacy increased. Such information will aid the development and parameterisation of models of close contact diseases, and may have direct use in outbreak investigations.  相似文献   
993.
紫外分光光度法测定平阳霉素霜的含量   总被引:2,自引:0,他引:2  
目的:用紫外分光光度法测定平阳霉素霜的含量,为该药提供质量控制方法。方法:紫外分光光度法。结果:平阳霉素甲醇液在293.5nm处有最大吸收,在30-70μg/ml范围内吸收度与浓度有良好线性关系,其回归方程为A=0.01066C-0.008(r=0.9998),平均回收率(n=5)为100.05%,RSD=0.98%。结论:该法作为平阳霉素霜剂的含量测定方法、快捷准确、简便易行,适用于医院快检。  相似文献   
994.
CYP2J2 is abundant in human heart and its arachidonic acid metabolites, the epoxyeicosatrienoic acids (EETs), have potent vasodilatory, antiinflammatory and cardioprotective properties. This study was designed to examine the role of CYP2J2 in hypoxia-reoxygenation-induced injury in cultured bovine aortic endothelial cells (BAECs). Early passage BAECs were exposed to 24-h hypoxia followed by 4-h reoxygenation (HR). HR resulted in cell injury, as indicated by significant increases in lactate dehydrogenase (LDH) release and trypan blue stained cells (p < 0.01) and was associated with a decrease in CYP2J2 protein expression. Transfection of BAECs with the CYP2J2 cDNA resulted in increased CYP2J2 expression and arachidonic acid epoxygenase activity, compared with cells transfected with an irrelevant green fluorescent protein (GFP) cDNA. HR induced significant injury in GFP-transfected BAECs, as indicated by increases in LDH release and trypan blue-stained cells (p < 0.01); however, the HR-induced injury was markedly attenuated in CYP2J2-transfected cells (p < 0.01). HR increased cellular 8-iso-prostaglandin F(2alpha) (p < 0.05), and decreased eNOS expression, L-arginine uptake and conversion, and nitrite production (p < 0.01) in GFP-transfected BAECs. CYP2J2 transfection attenuated the HR-induced increase in 8-iso-prostaglandin F(2alpha) (p < 0.05) and decreased the amount of extracellular superoxide detected by cytochrome c reduction under normoxic conditions (p < 0.05) but did not significantly affect HR-induced decreases in eNOS expression, L-arginine uptake and conversion, and nitrite production. Treatment of BAECs with synthetic EETs and/or epoxide hydrolase inhibitors also showed protective effects against HR injury (p < 0.05). These observations suggest: (1) HR results in endothelial injury and decreased CYP2J2 expression; (2) transfection with the CYP2J2 cDNA protects against HR injury; and (3) the cytoprotective effects of CYP2J2 may be mediated, at least in part, by antioxidant effects.  相似文献   
995.
996.
Hereditary Neuralgic Amyotrophy (HNA) is genetically heterogeneous   总被引:1,自引:1,他引:0  
Hereditary Neuralgic Amyotrophy (HNA) is an autosomal dominantly inherited recurrent focal neuropathy affecting mainly the brachial plexus. Linkage to markers on chromosome 17q25 was found in 1996 and subsequent reports confirmed linkage of HNA to this locus. Recently a family with a chronic undulating rather than remitting-relapsing clinical course of HNA was described by a Dutch group. This family did not have linkage to the 17q25 locus. Here we describe for the first time clinically and genetically two families with classic remitting-relapsing HNA that are not linked to the previously described HNA locus on chromosome 17q25. These results demonstrate that clinically homogeneous classical HNA is genetically heterogeneous. Received: 24 January 2001, Received in revised form: 19 March 2001, Accepted: 4 April 2001  相似文献   
997.
998.
BACKGROUND: In this prospective, cohort study of 15 children (median age 7.7 years, range 4.9-16.5 years) undergoing atrial septal defect repair, we evaluated changes in the Bispectral index (BIS) as a potential monitor of level of consciousness during cardiac anaesthesia. METHODS: Identical cardiac surgery, cardiopulmonary bypass (CPB) and anaesthetic techniques were used, including mild hypothermia and an early extubation protocol. BIS, mean arterial pressure, heart rate and tympanic temperature were recorded at baseline postinduction (Tbaseline), skin incision (Tincis), sternotomy (Tsternot), aortic cannulation (Tcann), nadir temperature (Tnadir), rewarmed (Trewarmed), immediate post-CPB (TpostCPB), chest drain insertion (Tdrains), sternal wires (Twire), skin closure (Tclosed) and spontaneous movement (Tmove). As a measure of stress response, serum lactate, glucose, norepinephrine and epinephrine levels were measured at Tbaseline, Tsternot, Tcann, Tnadir, Trewarmed and Tdrains. Explicit memory testing was undertaken prior to hospital discharge. RESULTS: BIS increased significantly during the rewarming phase (Trewarmed versus Tbaseline and Tnadir, P<0.001). Lactate, epinephrine and glucose levels were also significantly elevated at Trewarmed. There were no correlations between BIS and the increase in epinephrine, lactate and glucose during rewarming, nor with changes in heart rate or mean arterial pressure during surgery. All patients had an uneventful recovery without evidence for explicit recall. CONCLUSIONS: The increase in BIS during the rewarming phase could reflect an increase in conscious level, and is consistent with the reported risk for awareness during this phase of cardiac surgery.  相似文献   
999.
COMPLICATIONS OF URETEROSCOPY: ANALYSIS OF PREDICTIVE FACTORS   总被引:23,自引:0,他引:23  
PURPOSE: Although overall and major complication rates of 10% to 20% and 0% to 6%, respectively, have been observed in large series of ureteroscopy, to our knowledge no systemic analysis to determine factors predictive of these complications has been reported. MATERIALS AND METHODS: We retrospectively reviewed all ureteroscopies performed at our institution for calculous disease from January 1997 through September 1999. A total of 322 procedures were performed by 5 attending surgeons. Intraoperative and immediate postoperative complications were identified. Bivariate and multivariate analysis was performed to identify associated factors with ureteral perforation and postoperative complications as the dependent variables. RESULTS: Bivariate analysis showed a significant association of ureteral perforation with increased operative time (p = 0.0001). In addition, we noted a significant association of postoperative complications with stones in the kidney (p = 0.0004), operative time (p = 0.05) and decreased surgeon experience (p = 0.0035) as well as a trend toward significance for the type of ureteroscope used (p = 0.0609). In multivariate logistic regression models ureteral perforation remained highly associated with operative time (p = 0.0005) when controlling for the other factors. Similarly decreased surgeon experience and a stone in the kidney were predictive of postoperative complications when controlling for the other factors (p = 0.004). CONCLUSIONS: Longer duration of the ureteroscopic procedure is strongly associated with ureteral perforation. The likelihood of immediate postoperative complications is greater when renal calculi are treated and less when the surgeon is more experienced.  相似文献   
1000.
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