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91.
Hypertension is usually managed on a case-finding basis, and yet continued blood pressure control can be inadequate. Furthermore, hypertension is often a ‘silent’ condition until comorbid events, target organ damage and subsequent heart failure become manifest, leading to a reactive rather than a proactive approach. Management of the hypertension syndrome becomes complex, because blood pressure control may not be just an isolated concern. This review considers the various options, in addition to existing guidelines, that can help to reduce hypertension-related morbidity and mortality. 相似文献
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93.
Obstruction of the small intestine: accuracy and role of CT in diagnosis 总被引:17,自引:0,他引:17
Maglinte DD; Gage SN; Harmon BH; Kelvin FM; Hage JP; Chua GT; Ng AC; Graffis RF; Chernish SM 《Radiology》1993,188(1):61
94.
我们成功地建立了一个新的层析等电点聚焦的三步程序.细菌培养液首先以CG-50吸附,洗脱出的粗毒素溶液在PBE_(94)柱上进行层析等电点聚焦.分别用5mMTris-Base pH9.4和Buffalyte_(8-4) pH5.4缓冲液洗脱,出现多个洗脱峰,即刻测定pH值.收集pH6.8~7.1的洗脱液,混合、浓缩,最后通过Sephacryl s-200过滤,以0.05M PBS pH6.8洗脱,出现3个峰,毒素在第1峰.毒素纯度为98%,回收率89%,p17.6,MW28500,SDS-PAGE上1条带.以~(125)I标记SED作探针的电泳转移和放射自显影均证明了提纯SED的免疫学特异性.免疫扩散试验,即使200μg/ml SED与不产毒素的FRI-184抗血清,也未有可见沉淀线. 相似文献
95.
We investigated whether cigarette smoking, measured by follicular fluid
concentrations of cotinine (a major metabolite of nicotine), affects the
maturity of oocytes from women undergoing in-vitro fertilization (IVF) and
embryo transfer. In 234 women, follicular fluid samples were assessed for
cotinine and their 2020 oocytes were assessed for maturity stage. Data on
individual proportions of oocytes which were mature (OM) and were
fertilized (OF) were analysed by regression in relation to age and
follicular fluid cotinine. OF gave an independent assessment of oocyte
maturity. Both age and follicular fluid cotinine entered the OM and OF
regressions and were significant. The age-adjusted regression coefficients
for log cotinine were positive; greater cotinine concentrations usually
accompanied greater OM and OF. The cotinine effect on OM was positive in
younger women, but it became negative (decreased OM with increasing
cotinine concentrations) in older women (> or = 40 years). We further
found in older women an average reduction of approximately 50% in the
number of mature oocytes; this reduced number was lower than the number of
embryos usually transferred. Smoking can reduce the number of mature
oocytes even further, therefore risking a negative IVF-embryo transfer
outcome. This may be the reason why the negative effects of smoking become
clinically detectable in older women.
相似文献
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Papillary endolymphatic sac tumors: CT, MR imaging, and angiographic findings in 20 patients 总被引:6,自引:0,他引:6
99.
100.
To quantitatively map and compare patterns of regional cardiac metabolism with greater spatial resolution than is possible with positron emission tomography (PET), the authors developed autoradiographic techniques for use with combinations of radiolabeled fluorodeoxyglucose (FDG), glucose (GLU), and acetate (ACE) and applied the techniques to normal rats. Kinetic models were developed to compare GLU-based oxidative glucose metabolism with FDG-based total glucose metabolism (oxidative plus anaerobic) and to compare ACE-based overall oxidative metabolism with FDG-based total glucose metabolism. GLU-based metabolism generally paralleled FDG-based metabolism, but divergence occurred in certain structures such as the papillary muscles, where FDG-based metabolism was much greater. ACE-based metabolism also generally paralleled FDG-based metabolism, but again, the papillary muscles had relatively greater FDG-based metabolism. These discrepancies between FDG-based metabolism and GLU- or ACE-based metabolism suggest the presence of high levels of anaerobic glycolysis. Thus, the study indicates that anaerobic glycolysis, in addition to occurring in ischemic or "stunned" myocardium (as has been shown in recent PET studies), occurs normally in specific cardiac regions, despite the presence of abundant oxygen. 相似文献