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排序方式: 共有1310条查询结果,搜索用时 62 毫秒
101.
Ventral hernia repair: a study of current practice   总被引:5,自引:5,他引:0  
Ventral wall hernias are common; despite this, there are no guidelines on the best surgical management. The aim of this study was to examine the types of repair in use for abdominal wall hernias in the West of Scotland over a 3-month period. Data were gathered on 120 patients. There were 60 incisional, 32 umbilical, and 28 epigastric hernias. The main indication for repair was pain (78%), while 12 patients (10%), presented acutely with incarceration or strangulation. The most common method of repair was sutured (55%), followed by mesh (29%) and Mayo repair (16%). There was no correlation between use of mesh and hernia size or whether repair was for a recurrent hernia. Surgical practice varies widely in the repair of ventral wall hernias. Clinical trials are required to establish the best method of repair for this common condition. Electronic Publication  相似文献   
102.
A comparison of cycle control, efficacy and tolerability of two oral contraceptive preparations containing 20 microg ethinylestradiol combined with either 100 microg levonorgestrel (EE/LNG 20/100) or 500 microg norethisterone (EE/NET 20/500) was conducted. These results were compared to a standard reference preparation, containing 30 microg ethinylestradiol combined with 150 microg levonorgestrel (EE/LNG 30/150). Efficacy data from 8,544 treatment cycles were obtained from 767 women. Good cycle control and effective contraception was achieved with the two LNG preparations, however, the cycle control results were less favorable with EE/NET 20/500. The cumulative incidence of women with at least one episode of intermenstrual bleeding from cycles 2 to 7 (primary target variable) was 43.9% for EE/LNG 20/100, 72.7% for EE/NET 20/500, and 15.7% for the standard EE/LNG 30/150. The difference between the 2 20 microg of EE preparations, which favored EE/LNG 20/100, was statistically significant (p = 0.001). The overall spotting rates (cycles 1-13) were 9.3% for EE/LNG 20/100, 21.7% for EE/NET 20/500, and 3.3% for the standard EE/LNG 30/150. Amenorrhea was reported in 7.1% (EE/LNG 20/100), 20.6% (EE/NET 20/500), and 0.9% (standard EE/LNG 30/150), respectively. Intermenstrual bleeding episodes were shorter with EE/LNG 20/100 and EE/LNG 30/150 of the 13 treatment cycles. The study Pearl indices were 0.9 for EE/LNG 20/100, 1.9 for EE/NET 20/500, and 0.0 for EE/LNG 30/150. All three treatments were well tolerated. However, tolerability was somewhat less favorable with EE/NET 20/500. A total of 160 women prematurely discontinued the study for various reasons (EE/LNG 20/100: 7%; EE/NET 20/500: 18%; EE/LNG 30/150: 4%). The overall adverse event incidence rate during the trial was low in all groups. Blood pressure remained largely unaffected. Thirteen serious adverse events were recorded for all treatment groups, all but one were assessed as not related to the treatments. There were no remarkable treatment related differences in mean body weight throughout the study and the laboratory values were largely unaffected in all three treatments groups.  相似文献   
103.
目的构建人端粒酶逆转录酶(hTERT)片段的真核表达质粒。方法用RT-PCR方法从肝癌组织中提取总RNA扩增出hTERT基因片段,将其连接pGEM-TEasy质粒上,将重组质粒pGEM-T-hTERT和pEGFP-C3真核绿色荧光蛋白表达载体同时用HindⅢ和BamHⅠ双酶切后进行连接,再将重组的pEGFP-C3-hTERT基因片段转染NIH3T3细胞,经G418筛选获得稳定转染的细胞系,荧光倒置显微镜观察并检测转染细胞的hTERTmRNA表达水平。结果DNA序列分析证实了重组载体pGEM-T-hTERT和pEGFP-C3-hTERT内插入片段的碱基组成与公开发表的hTERT序列一致。转染pEGFP-C3-hTERT的NIH3T3细胞可见绿色荧光,并检出高水平表达的hTERT。结论成功构建高效表达hTERT的真核表达载体,为以hTERT为靶点的肿瘤治疗打下实验基础。  相似文献   
104.
目的:该实验旨在研究急性肺损伤(ALI)时肺泡Ⅱ型上皮细胞(AEC-Ⅱ)超微结构变化和肺组织表面活性蛋白SP-A含量的变化关系,从而探讨ALI的发病机制。方法:48只Sprague-Dawley幼鼠被随机分为正常对照组和ALI组。 腹腔注射脂多糖(LPS,4 mg/kg)建立ALI模型,正常对照组注射等量生理盐水。 LPS注射后24,48,72 h每亚组各处死8只大鼠。 取左肺下肺组织待透射电镜检查。 用Western blot方法测定肺组织SP-A的相对含量。结果:ALI 24 h时,AEC-Ⅱ微绒毛消失。24 h及48 h时板层小体(lamellar body, Lb)数量增加,体积增大,密度减低,排空明显增强,呈指环状绕核排列,细胞增生活跃,代谢旺盛。48 h时Lb呈巨大空泡样变性。肺组织SP-A含量明显高于对照组(24 h时ALI组为6.52±0.62,对照组为5.02±0.35, P< 0.01;48 h时ALI组为6.65±0.62,对照组为5.01±0.36,P< 0.01)。72 h时Lb破溃,数目明显减少,细胞核形态不规则,部分核边界不清,肺组织SP-A含量下降(ALI组为3.87±0.50,对照组为5.22±0.36,P<0.01)。结论: LPS致幼鼠ALI时AEC-Ⅱ和肺组织SP-A的变化为时间依赖性,随AEC-Ⅱ损伤程度的加重肺组织SP-A由代偿转为失代偿,可能是发生ARDS的重要机制之一。  相似文献   
105.
通过探讨细化药品采购环节:包括建立和完善采购制度,优选药品配送企业,制定合理的采购时间、合理采购价格和合理的库存结构及库存水平。以便及时、准确地为临床用药提供安全、有效、经济的药品以及全方位保障药品供应。  相似文献   
106.
107.
108.
Digital beam attenuator technique for compensated chest radiography   总被引:1,自引:0,他引:1  
The feasibility of producing patient-specific beam attenuators for chest radiography has been investigated using an anthropomorphic phantom and a human volunteer. A low-dose test exposure is digitized, processed, and used to print a small cerium filter, which is placed in the x-ray beam near the collimator. The final radiograph is recorded on film. The technique results in relatively uniform film exposure, so that structures in all regions of the chest are simultaneously displayed with optimal film contrast. The equalized exposure improves image quality in the normally underpenetrated regions and reduces the role of cross-scatter from the lungs. The image is analogous to optical or computer-processed unsharp masking techniques, but the processing is accomplished in the x-ray beam and results in an improved exposure distribution, giving advantages that cannot be achieved with image processing techniques alone.  相似文献   
109.
110.
Helms  CA; Sims  R 《Radiology》1986,160(1):153-154
A normal variant, the foraminal spur, is described in five patients. It was seen on computed tomographic studies as a bony process extending from either the pars or the pedicle into the neuroforamen dorsal to the nerve root. In four of the cases it was seen bilaterally. None of the patients had any symptoms related to these spurs. No associated disease of the neuroforamen or facet was present. These spurs most likely represent ossification of the ligamentum flavum at its point of insertion and should not be mistaken for osteophytes, free disk fragments that have calcified, or fracture fragments. Sagittal reformations are helpful in visualizing the extent of the foraminal spurs.  相似文献   
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