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991.
Sepsis syndrome and septic shock remain significant causes of morbidity and mortality. To date, clinical trials of novel agents to treat sepsis have failed to demonstrate clinical efficacy despite considerable animal data to suggest a positive therapeutic benefit. This article reviews the recent major clinical trials on sepsis and discusses the hypotheses on which these therapies are based and the critical issues associated with clinical sepsis. Recommendations for future clinical trials on sepsis are made.  相似文献   
992.
Three fecal egg count reduction assays (FECR) and one critical trial were performed to determine the efficacy of pyrantel pamoate (PP) at 6.6 mg base kg-1 on a well managed stud farm in Louisiana where a loss of efficacy was suspected. Efficacy of PP based on FECR varied from 25% in mares to 83% in yearlings. Second treatments with PP 2 weeks following an initial treatment failed to reduce eggs per gram (EPG). A critical trial was performed to determine the cyathostome species resistant to PP. Three strongyle-naive ponies which acquired infections on the farm were used for this purpose. Following treatment with PP at the recommended dose, 11 species of cyathostomes remained in the intestine of the tracer ponies. Reduced efficacies (62%-88%) were noted for seven species. Resistance to oxibendazole (OBZ), which was > 90% effective on this farm in 1982, was also evaluated by FECR and found to exist. The results of one experiment indicate that dual resistance of parasites to PP and OBZ also exists.  相似文献   
993.
During the period of 1977 to 1990, 960 Carpentier-Edwards standard prostheses (Baxter Healthcare Corp., Santa Ana, Calif.) were placed in 875 operations. Freedom from reoperation at 10 years was 57% +/- 4%, 76% +/- 3%, and 95% +/- 5% for mitral, aortic, and tricuspid valve replacement, respectively. Age was the only independent determinant of reoperation for both aortic and mitral valves. Likelihood of reoperation decreased with age, with freedom from reoperation after 10 years in patients aged less than 60 years versus 60 or more years being 65% +/- 5% versus 90% +/- 4% after aortic valve replacement and 48% +/- 5% versus 75% +/- 6% after mitral valve replacement. For mitral valve replacement, larger valve size made reoperation more likely, with freedom from reoperation at 10 years being 71% +/- 6% for sizes median less than 31 mm and 57% +/- 5% for sizes 31 mm or larger. For aortic valve replacement, prior median sternotomy reduced freedom from reoperation at 10 years from 80% +/- 3% to 25% +/- 5%. The low prevalence of reoperation affirms the suitability of the Carpentier-Edwards prosthesis for selected elderly patients and for tricuspid valve replacement. Because of their influence on the probability of reoperation, valve size and prior cardiac procedures also merit consideration in the choice of valvular prosthesis.  相似文献   
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Resistance to insulin-mediated glucose disposal is a common finding in patients with non-insulin-dependent diabetes mellitus (NIDDM), as well as in nondiabetic individuals with hypertension. In an effort to identify the generic loci responsible for variations in blood pressure in individuals at increased risk of insulin resistance, we studied the distribution of blood pressure in 48 Taiwanese families with NIDDM and conducted quantitative sib-pair linkage analysis with candidate loci for insulin resistance, lipid metabolism, and blood pressure control. We found no evidence for linkage of the angiotensin converting enzyme locus on chromosome 17, nor the angiotensinogen and renin loci on chromosome 1, with either systolic or diastolic blood pressures. In contrast, we obtained significant evidence for linkage or systolic blood pressure, but not diastolic blood pressure, to a genetic region at or near the lipoprotein lipase (LPL) locus on the short arm of chromosome 8 (P = 0.002, n = 125 sib-pairs, for the haplotype generated from two simple sequence repeat markers within the LPL gene). Further strengthening this linkage observation, two flanking marker loci for LPL locus, D8S261 (9 cM telomeric to LPL locus) and D8S282 (3 cM centromeric to LPL locus), also showed evidence for linkage with systolic blood pressure (P = 0.02 and 0.0002 for D8S261 and D8S282, respectively). Two additional centromeric markers (D8S133, 5 cM from LPL locus, and NEFL, 11 cM from LPL locus) yielded significant P values of 0.01 and 0.001, respectively. Allelic variation around the LPL gene locus accounted for as much as 52-73% of the total interindividual variation in systolic blood pressure levels in this data set. Thus, we have identified a genetic locus at or near the LPL gene locus which contributes to the variation of systolic blood pressure levels in nondiabetic family members at high risk for insulin resistance and NIDDM.  相似文献   
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The authors examined 1) effects of nortriptyline (NT) on electroencephalographic (EEG) sleep measures in elderly patients with bereavement-related depression in remission under randomized, double-blind, placebo-controlled conditions, and 2) the effects of clinical remission on sleep after discontinuation of medication. Subjects were classified as responders to placebo (n = 9) or NT (n = 18) and had EEG sleep studies at three time-points: before treatment (T1), remitted on medication or placebo (T2), and remitted off medication or placebo (T3). As compared with placebo, NT was differentially associated with decreases in REM sleep time and percent and increases in REM sleep density (T2). No changes in EEG sleep measures occurred in placebo responders. REM sleep measures in NT responders reverted to T1 levels after T3, with persistence of robust clinical remission and normal subjective sleep quality. These data suggest that NT alters REM sleep, but that EEG sleep characteristics in bereavement-related depression persist into remission.  相似文献   
999.
研究了Si和Si尖上纳米金刚石场电子发射性质。纳米金刚石是利用热灯丝CVD法合成的,反应气体是CH4、N2和H2的混合物。实验结果表明Si衬底上的纳米金刚石特别是Si尖上的金刚石与多晶金刚石相比,前者极大地改善了场发射性质。场发射电场阈值和电流与金刚石晶粒度密切相关。文中对其结果进行了讨论。  相似文献   
1000.
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