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排序方式: 共有1937条查询结果,搜索用时 125 毫秒
1.
Jennifer Wang Jonathan G. Stine Scott L. Cornella Curtis K. Argo Steven M. Cohn 《临床与转化肝病杂志(英文版)》2015,3(4):254-259
Background and Aims: Gastric antral vascular ectasia (GAVE) is commonly found in patients with cirrhosis, but it is also associated with other diseases in the absence of cirrhosis. Whether GAVE confers a different severity of gastrointestinal (GI) bleeding between patients with and without cirrhosis remains unknown. We aim to examine whether there is a difference in clinically significant GI bleeding due to GAVE in patients with or without cirrhosis. Methods: This is a retrospective case-control study of patients who were diagnosed with GAVE between January 2000 and June 2014. Patients were categorized into cirrhosis and noncirrhosis groups, and those with an additional GI bleeding source were excluded. Univariate comparisons and multivariable models were constructed using logistic regression. Results: In total, 110 patients diagnosed with GAVE on esophagogastroduodenoscopy (EGD) were included in our analysis; 84 patients had cirrhosis (76.4%) and 26 (23.6%) did not. Active GI bleeding was more prevalent in patients without cirrhosis (63.4% vs. 32.1%, p=0.003) despite similar indications for EGD, and endoscopic treatment with argon plasma coagulation (APC) was required more often in this group, approaching statistical significance (27% vs. 10.7%, p=0.056). There was no difference in bleeding severity, as evidenced by similar re-bleeding rates, surgery, or death attributed to uncontrolled bleeding. The strongest independent risk factor for GI bleeding was the absence of cirrhosis (odds ratio (OR): 5.151 (95% confidence interval (CI): 1.08-24.48, p=0.039). Conclusions: Patients with GAVE in the absence of cirrhosis are at higher risk for active GI bleeding and require more frequent endoscopic treatment than similar patients with cirrhosis. It may be worthwhile to treat GAVE in this population even in the absence of active bleeding. 相似文献
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Background: We evaluated the endoscopic microvascular architecture of the gastric mucosa in portal hypertension patients using the prototype of narrow band imaging (NBI). Material and Methods: The study included 103 Helicobacter pylori‐negative patients with chronic liver disease (22 without portal hypertension (group 1), 81 with portal hypertension (group 2)). Results: (i) Abnormality of collecting venules, reddening mucosa, red spots, a mosaic‐like pattern, and gastric antral vascular ectasia (GAVE) were observed on the gastric mucosa, and an obscure change in collecting venules (73% vs 14%; P < 0.001), reddening mucosa (49% vs 5%; P < 0.001), red spots (36% vs 5%; P < 0.01) and a mosaic‐like pattern (40% vs 5%; P < 0.01) were more frequently observed in group 2 than in group 1. (ii) On magnifying endoscopy with NBI, the mucosa with an obscure change in collecting venules was demonstrated as dilation of the capillaries surrounding the gastric pits in various degrees, and reddening mucosa was observed as extended and swollen gastric pits and various degrees of dilated and convoluted capillaries surrounding the gastric pits. Red spots were demonstrated as extended and swollen gastric pits, dilated and convoluted capillaries surrounding the gastric pits, and intramucosal hemorrhage around these capillaries. GAVE was recognized as partial and marked dilatation of the capillaries surrounding the gastric pits. Conclusion: Abnormality of collecting venules, swelling of gastric pits, dilatation of capillaries surrounding the gastric pits, intramucosal hemorrhage around capillaries, and partial and marked dilatation of the capillaries were observed on the gastric mucosa in portal hypertension patients. 相似文献
3.
NICOLAY GENOV BRUNO FILIPPI PAVLINA DOLASHKA KEITH S. WILSON CHRISTIAN BETZEL 《Chemical biology & drug design》1995,45(4):391-400
The stability towards thermal and chemical (guanidine hydrochloride, GnHCl) denaturation of six inhibited subtilases (mesentericopeptidase, subtilisins BPN′, Carlsberg and DY, proteinase K and thermitase) has been investigated by kinetic and equilibrium studies. The unfolding processes were monitored by circular dichroic and fluorescence spectroscopy. Experiments in the absence and presence of extraneous calcium in the concentration range 2×10?3-10?1 M were performed. The presence of calcium in the weak calcium binding site changes the denaturation drastically. The heat- (or GnHCl-) induced unfolding curves obtained using CD spectroscopy show two independent transitions which seem not to have been resolved before. The presence of Ca2+ in the second (third in the case of thermitase) binding site increases the Tm, values by 11-21 °C and the δGD(H2O) values obtained from denaturation experiments in GnHCl by 6.7-7.2 kcal/mol when an extraneous Ca2+ concentration of 2 × 10?2 M was used. One interpretation is that the initial step of denaturation in the presence of added calcium is the formation of a partially unfolded intermediate form, retaining a highly ordered structure with 60-85% of the a-helix structure of the native enzyme. This intermediate then unfolds at a temperature considerably higher than that of the same proteinases in the absence of added Ca2+. The free energy of stabilization of the intermediates is increased by 1.8-2.8 times in comparison with that for the unfolding reactions of the subtilases with empty Ca2/Ca3 binding sites. A second interpretation is that the two steps in the unfolding curves correspond to enzyme without and with calcium in the weak binding site. Fluorescence experiments confirm the mechanism involving the formation of intermediate states. The results are discussed in relation to the X-ray models of the six subtilases. 相似文献
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以往以乳头为圆心的同心圆剥离法常形成假体的移位,使假体的体表轮廓与前方的自然乳房分离,产生“双重乳房”现象。在研究了女性不同体位下不同的乳房形态及总结了以前的经验后,提出了偏心圆剥离的概念。偏心圆手术设计方法:以乳头为圆心,按其内侧、下侧为直径3/5的比例,以外侧、上侧为直径2/5的比例,形成一偏心圆的剥离范围。偏心圆的直径因考虑到假体的不同形态、大小及底面直径,以经中心假体纵截面的周长的1/2再放大2cm,作为剥离范围的直径。自1991年10月以来已应用了176例,无一术后移位现象,也没有固较多地剥离胸大肌内、下侧止点纤维而影响上肢活动。自然乳房并不是静态的圆锥形或半球形,它具有伸缩的组织学特点,又有随体位变动而变化的特点。用偏心圆法剥离,可使置入的假体与前方的自然乳房融为一体,消除“双重乳房”现象,而成为“真实”的乳房。同时也应积极寻找一种与身体组织相容性好的,弹性、比重与女性乳腺较为一致的,假体容量相对恒定的生物性材料。这样隆乳术才可以更广泛地开展。 相似文献
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理气类中药对大鼠离体胃平滑肌条的作用 总被引:9,自引:0,他引:9
目的:观察理气类中药对大鼠离体胃平滑肌条运动的影响。方法:将肌条放置在灌流肌槽中,用生理记录仪记录肌条的收缩活动。结果:陈皮、枳实对胃各部位平滑肌条均为抑制效应,香附、薤白、木香、柿蒂、乌药对胃底肌条为兴奋效应,但对其他部位肌条则表现为兴奋或抑制不同的效应,沉香仅降低胃窦环行肌收缩波平均振幅,对其他肌条无影响。结论:理气类中药对大鼠离体胃平滑肌条既有兴奋作用,也有抑制作用。 相似文献
9.
Circular stereotactic callosotomy: A preliminary report 总被引:1,自引:0,他引:1
P. Nádvornik P. Krupa J. Chrastina V. Smrčka Z. Novák E. Zbofřilová 《Acta neurochirurgica》1997,139(4):359-360
Summary The authors propose a new method for performing Stereotactic callosotomy, which they have named circular callosotomy. The operating device is the original Riechert-Mundinger's string electrode, which can be protruded through a side window and by rotating the probe it is possible to cut the commisural pathways to the extent required. The anatomical results of the operation can be checked using MRI scanning. 相似文献
10.
目的确定蝇类季节消长的高峰日和高峰时段,为制定蝇类防制措施提供科学依据。方法用圆形分布法统计分析绍兴市区2003-2004年蝇类密度监测数据。结果绍兴市区2003-2004年蝇类平均密度高峰日为8月4日,高峰时段为6月8日至9月30日。其中2003年蝇类密度高峰日为8月11日,高峰时段为6月17日至10月5日;2004年蝇类密度高峰日为7月29日,高峰时段为6月1日至9月26日。结论绍兴市区2年中蝇类消长有明显的季节性规律。 相似文献