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1.
目的:研究Visumax飞秒激光辅助的准分子激光原位角膜磨镶术(LASIK)术中不透明气泡层(OBL)产生的类型、相关影响因素及其临床意义。方法:回顾性分析。收集2016 年7 月1 日至8 月20 日在南京医科大学附属眼科医院行飞秒LASIK的患者154 例(300 眼)的临床资料,等效球镜度为(-5.88±1.51)D。飞秒激光采用Zeiss公司 Visumax飞秒激光仪,将术中产生的OBL分为瓣外OBL、瓣内快速OBL和瓣内慢速OBL。300 眼按角膜曲率平均K值分为A组(<42 D)、B组(42~46 D)和C组(>46 D);按角膜瓣的厚度分为D组(100 μm)、E组(110 μm)和F组(120 μm);按角膜厚度分为G组(<500 μm)、H组(500~540 μm)和I组(>540 μm)。统计不同角膜曲率、角膜瓣厚度、角膜厚度情况下3 种OBL产生的比例,并采用多元Logistic回归模型进行统计分析。结果:300 眼均发生OBL。以瓣外OBL作为参照,角膜瓣越薄,越容易出现瓣内快速OBL(r=-0.719,P=0.034)和瓣内慢速OBL(r=-0.875,P=0.044)。以瓣内慢速OBL作为参照,角膜曲率越高,越容易出现瓣内快速OBL(r=0.923,P=0.046);角膜瓣越厚,越容易出现瓣外OBL(r=0.897,P=0.044)。结论:OBL的产生与角膜曲率、角膜瓣厚度、角膜厚度均存在一定的相关性,但瓣外OBL、瓣内快速OBL和瓣内慢速OBL对Visumax飞秒激光辅助的LASIK术后视觉质量的影响及远期疗效仍有待进一步观察研究。 相似文献
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By injecting small amounts of CO2 through a needle, one can move bowel or bladder from the intended path of instruments during interventional procedures. The technique worked well in six of seven cases in the pelvis and retroperitoneum; it was not effective in the mediastinum or midabdomen (n = 6). 相似文献
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In Vivo Molecular Imaging Characterizes Pulmonary Gene Expression During Experimental Lung Transplantation 总被引:2,自引:0,他引:2
Sekhar Dharmarajan Makio Hayama James Kozlowski Takaaki Ishiyama Mikio Okazaki Phillip Factor G. Alexander Patterson Daniel P. Schuster 《American journal of transplantation》2005,5(6):1216-1225
Experimental gene therapy is a promising strategy to prevent ischemia-reperfusion (I/R) injury and allograft rejection after lung transplantation, and methods will eventually be needed to characterize pulmonary transgene expression in vivo in humans. Therefore, we studied positron emission tomography (PET) as a means of performing in vivo molecular imaging in rodent models of lung transplantation. Rats were transfected endotracheally with adenovirus encoding a fusion gene of a mutant Herpes simplex virus-1 thymidine kinase and the green fluorescent protein gene (the former serving as an imaging reporter gene). Twenty-four hours after transfection, lungs were transplanted in groups representing normal transplantation, I/R injury and acute allograft rejection. Imaging was obtained either 24 h after transplantation to study reperfusion injury or 4 days after transplantation to study graft rejection. After imaging, lungs were excised and analyzed for thymidine kinase activity. Imaging detected transgene expression in transplanted lungs even in the presence of acute rejection or I/R injury. The PET imaging signal correlated with in vitro lung tissue assays of thymidine kinase activity (r(2) = 0.534). Thus, noninvasive molecular imaging with PET is a feasible, sensitive and quantitative method for characterizing pulmonary transgene expression in experimental lung transplantation. 相似文献
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外科医生和手术室人员经常接触手术设备产生的烟气,病人也会暴露于烟气中,特别是腹腔镜手术中产生的烟气滞留于腹腔内这一密闭空间并被吸收.这些烟气是一种与香烟烟气相似的毒性物质,然而对这种毒性物质的影响还未引起足够重视.应该采取必要措施尽可能减少手术中烟气的不良影响. 相似文献
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Different morphologic and density classes of sickle cells (SS) may play distinct roles in the generation of vasoocclusion, explaining the complexity of this phenomena. The densest SS red blood cells (RBCs) (SS4) can induce vasoocculsion in ex vivo microcirculatory preparations as well as in an intact animal model. Previous studies of the interaction of SS deformable discocytes with endothelial monolayers or the rat ex vivo mesocecum preparation have shown adhesion that is desmopressin (dDAVP)-stimulated, von Willebrand factor (vWF)-mediated, and limited to the small venules. However, in vivo adhesion of SS RBCs to the endothelium has neither been demonstrated nor characterized; and, in particular, the relation of adhesion to vasoocclusion is unknown. Using an intact animal model that involves injecting saline-washed, density-defined SS RBCs into the femoral artery of a rat, we find that: (1) Quantitative studies of RBCs retained in the rat thigh using 99mTc-labeled RBCs and gamma camera imaging showed that dDAVP induces a threefold increase in retention of normal (AA) cells and deformable SS discocytes (SS2). (2) electron microscopy and Microfil injection show that the retention of SS2 cells is due to adhesion to the vascular endothelium with no evidence of obstruction. (3) H-1 magnetic resonance imaging showed that retention of SS4 cells induced a dose-dependent increase in tissue edema (presumable secondary to tissue hypoxia), while retention of AA or SS2 cells produced no change. We conclude that endothelial adhesion of deformable SS discocytes can be demonstrated in an in vivo animal model, that this adhesion is enhanced by dDAVP (presumably related to, but not necessarily limited to the release of vWF), and that this phenomenon per se does not lead to vasoocclusion. Nevertheless, adhesion of deformable SS discocytes may have consequences. We hypothesize that adhesion of SS discocytes could narrow the lumen of postcapillary venules and facilitate secondary trapping of SS4 cells and lead to subsequent vasoocclusion. 相似文献
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