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Endoscopic retrograde cholangiopancreatography has been part of clinical practice for over 35 years. The procedure itself carries risks. Most complications associated with the procedure have been described in the literature. Splenic injury is an extremely rare complication after endoscopic retrograde cholangiopancreatography and only nine such cases have been reported to our knowledge since 1988. We report on a patient who presented with abdominal pain and was found to have abnormal liver function and a dilated pancreatic duct. An endoscopic retrograde cholangiopancreatography was performed and a splenic laceration was noted subsequently. As this operation is an increasingly important diagnostic and therapeutic modality for pancreatico-biliary disease, clinicians must be aware of this complication in order to make an early diagnosis and begin appropriate management. 相似文献
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This article will outline a pragmatic approach directed to incorporating key elements of a scientific review of the literature and derive a proposal for an occupational exposure standard for coal tar, coal tar pitch, creosote, petroleum pitch, bitumen and asphalt, six substances which contain polynuclear aromatic hydrocarbons. Five approaches to the standard setting process are reviewed and their strengths and weaknesses discussed. Unfortunately there does not exist an acceptable epidemiological data set, other than the coke oven emission studies, on which to base a valid and reliable risk assessment model. Based on comparative potency experiments of complex mixtures, consideration of the state-of-the-art sampling and analytical methods, prevention of acute human health effects, and current existing standards for these substances throughout the world, a set of recommended exposure standards are derived for health policy makers. 相似文献
997.
R H Peters D F Crowe M Tanabe M A Avery W K Chong 《Journal of medicinal chemistry》1987,30(4):646-652
A number of silicon-substituted analogues of ethynylestradiol that exhibit modified and enhanced biological activities have been synthesized. Particularly noteworthy are a group of [(trialkylsilyl)ethynyl]estradiol analogues that exhibit high antifertility potency and markedly reduced estrogenic activity. The best compounds synthesized are 17 alpha-[(triethylsilyl)ethynyl]estradiol (5) and 17 alpha-[(tert-butyldimethylsilyl)ethynyl]estradiol (33), which show a separation of antifertility from estrogenic activity in the rat. The results of structure-activity studies indicate a good correlation between the observed biological activities and the calculated van der Waals volumes of the three variable silicon substituents. 相似文献
998.
目的:应用抑制性消减杂交(SSH)方法构建膀胱移行细胞癌(BTCC)患者与正常人尿脱落细胞差异表达基因cDNA消减文库。方法:分别从BTCC患者与正常人尿液中提取总mRNA,用SMART技术反转录成cDNA,经过HaeⅢ酶切后将BTCC尿脱落细胞cDNA分为两组并接上接头,再与过量正常膀胱尿脱落细胞cD-NA进行两轮消减杂交及两轮抑制性聚合酶链反应(PCR),使得差异表达的DNA片段得以富集。PCR产物与T/A载体连接并转化大肠杆菌JM109构建成差异表达基因的cDNA消减文库。文库扩增后,随机挑取克隆进行酶切、测序及同源性分析。结果:PCR鉴定有317个克隆载有主要在200~900bp之间呈随机分布的插入片段,片段插入率达82.6%,证实建库成功。对20个质粒测序结果经同源性比对分析,其中20个片段源于17个已知基因,1个克隆在GenBank中未检索到与其有相似性的基因序列,表明它们可能为BTCC差异表达的新基因。结论:该消减杂交文库质量可靠,其成功构建为进一步筛选、克隆BTCC差异表达基因提供了依据。 相似文献
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Gary S. Chong PhD Dennis Cogan PhD Patrick Randolph PhD Gabor Racz MD 《Pain practice》2001,1(4):338-343
Abstract: Higher self-efficacy (SE) is associated with lower pain ratings in chronic pain patients, although longer experience with chronic pain leads to lower SE scores. Self-efficacy in pain patients does not appear to be clearly related to sex or age, however. This study investigated the effects of gender, age, length of pain experience (chronicity) on SE and pain ratings.
Archival data from the records of 187 patient's charts were evaluated for demographic information, chronicity, pain ratings and SE. Analyses found a significant inverse relationship between SE and pain ratings (r = −.22) and lower SE for young adult patients. Results support the conclusion that enhanced SE is an important psychosocial intervention in the treatment of chronic pain patients. 相似文献
Archival data from the records of 187 patient's charts were evaluated for demographic information, chronicity, pain ratings and SE. Analyses found a significant inverse relationship between SE and pain ratings (r = −.22) and lower SE for young adult patients. Results support the conclusion that enhanced SE is an important psychosocial intervention in the treatment of chronic pain patients. 相似文献