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51.
强利敏  法卫玲  陈黎  蔡秋霞 《癌症进展》2021,19(13):1349-1351,1355
目的 探究食管支架置入术(ESP)和内镜下切开术(EIM)在难治性食管癌术后吻合口狭窄治疗中的应用效果.方法 将70例难治性食管癌术后吻合口狭窄患者按照手术方式不同分为ESP组(n=41)与EIM组(n=29).对比两组患者临床疗效、吞咽困难评分及并发症发生情况.结果 两组患者总有效率比较,差异无统计学意义(P>0.05).术前,两组患者Stooler评分比较,差异无统计学意义(P>0.05);术后1个月,两组患者Stooler评分均较术前降低(P<0.05),且EIM组患者Stooler评分明显低于ESP组(P<0.01).ESP组患者术后并发症总发生率高于EIM组(P<0.05).结论 EIM和ESP治疗难治性食管癌吻合口狭窄的临床疗效相当,EIM短期内对患者吞咽困难症状改善作用明显,且具有术后并发症少等优点.  相似文献   
52.
Urban renewal efforts are a priority for many American cities. As efforts to reconstitute urban centers increase, the demolition of old, deteriorated structures has accelerated. Recent studies have identified demolitions as a potential source of environmental lead exposure. We conducted a study examining the relationship between demolition activity and blood lead levels of children residing in neighborhoods where demolition activity occurred. A retrospective cohort study was conducted in St. Louis City, Missouri. The study period was January 1, 2002 to December 31, 2002. Data were obtained from the Missouri Childhood Lead Poisoning Prevention Program's (CLPPP) lead surveillance system and St. Louis Demolition Permit Database. Children were considered exposed to a demolition if they had a blood lead test within 45 days of any demolition on a census block. Exposure was classified as both a dichotomous (yes/no) and a categorical (none/one/multiple) variable and was analyzed separately. Linear regression models were developed to determine effects of demolitions on blood lead levels. A total of 1196 children 6-72 months of age living in 395 census blocks were included. 314 (26.3%) were exposed and 882 (73.7%) were unexposed to a demolition. In an adjusted model, exposure to multiple demolitions was found to have significant effects on children blood lead levels (coefficient=0.281; 95% CI=0.069, 0.493; P-value=0.010). Age of the child, race, and age of housing where children's resided were also significant predictors. This study suggests that multiple demolitions within a census block may significantly increase children's blood lead levels. The findings may be useful to municipal planners in older cities where demolitions are being used as an urban renewal tool.  相似文献   
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目的总结在体外循环辅助下,经右房切口治疗合并下腔静脉血栓形成的布-加氏综合征的治疗经验。方法回顾我院自2002年9月至2010年7月共计49例在体外循环辅助下,经右心房切口治疗合并下腔静脉血栓的布加氏综合征的临床病例和随访资料。结果全组病人均成功的在体外循环辅助下完成经右房切口下腔静脉狭窄段扩张及血栓取出术。术中在手指破膜后再使用3.0×4.0cm球囊进行扩张。围手术期病人无死亡,无急性肺栓塞等严重并发症的发生。术后随访0~36个月,所有病人术后症状明显缓解,腹水及下肢水肿减轻至消失。1例病人术后1年后出现再狭窄,经股静脉行下腔静脉球囊扩张后好转。全组病人术后随访未见有血栓形成。结论在体外循环下,经右房切口对于合并下腔静脉血栓的布-加氏综合征是一种安全有效的治疗方法。  相似文献   
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56.
Scott  MD; Eaton  JW; Kuypers  FA; Chiu  DT; Lubin  BH 《Blood》1989,74(7):2542-2549
To delineate further the role of superoxide dismutase (SOD) in red blood cell (RBC) oxidant defense, normal human erythrocytes were osmotically lysed and resealed in the presence of varying concentrations of exogenous SOD. This resulted in a dose-dependent increase in SOD activity in the resealed erythrocytes while maintaining nearly normal RBC hemoglobin concentration (less than 10% decrease from the control value), cell volume, and cellular deformability. Surprisingly, a five- or ninefold increase in SOD activity yielded no additional protection against superoxide-generating drugs (phenazine methosulfate or menadione sodium bisulfite). No significant differences were observed between the control and SOD-loaded RBCs in O2-driven methemoglobin formation or generation of thiobarbituric acid-reactive substances. In contrast, RBCs with elevated SOD activity pretreated with sodium azide (to block catalase activity) or 1-chloro-2,4- dinitrobenzene (to deplete reduced glutathione, GSH) showed significantly enhanced methemoglobin generation in response to superoxide generating drugs. No differential response was noted between the control, control-resealed, and SOD-loaded RBCs to oxidants other than superoxide. Based on our results and other data, we conclude that elevated SOD activity may imbalance cellular oxidant defense, resulting in enhanced oxidation due to the accelerated generation of H2O2, the product of O2- dismutation. This effect is significantly exacerbated under conditions in which H2O2 catabolism is altered.  相似文献   
57.
Myelinated and nonmyelinated nerves: comparison of proton MR properties   总被引:1,自引:0,他引:1  
Jolesz  FA; Polak  JF; Adams  DF; Ruenzel  PW 《Radiology》1987,164(1):89-91
The magnetic resonance (MR) relaxation rates of protons were compared in the myelinated and nonmyelinated nerves of the garfish. The long, large olfactory nerve of the garfish, as an easily accessible source of nonmyelinated axons, is uniquely suited for such a comparison. The T1 and T2 measurements revealed distinct and consistent differences between nonmyelinated olfactory nerves and myelinated optic and oculomotor nerves. Comparisons between water content, lipid content, and relaxation rates indicated that the differences in MR properties represent complex differences in the distribution and physical environment of the constituent lipid and water protons.  相似文献   
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Recent progress in oculomotor research has enabled new insights into the functional neuroanatomy of the human premotor oculomotor brainstem network. In the present review, we provide an overview of its functional neuroanatomy and summarize the broad range of oculomotor dysfunctions that may occur in Huntington's disease (HD) patients. Although some of these oculomotor symptoms point to an involvement of the premotor oculomotor brainstem network in HD, no systematic analysis of this functional system has yet been performed in brains of HD patients. Therefore, its exact contribution to oculomotor symptoms in HD remains unclear. A possible strategy to clarify this issue is the use of unconventional 100-µm-thick serial tissue sections stained for Nissl substance and lipofuscin pigment (Nissl-pigment stain according to Braak). This technique makes it possible to identify the known nuclei of the premotor oculomotor brainstem network and to study their possible involvement in the neurodegenerative process. Studies applying this morphological approach and using the current knowledge regarding the functional neuroanatomy of this human premotor oculomotor brainstem network will help to elucidate the anatomical basis of the large spectrum of oculomotor dysfunctions that are observed in HD patients. This knowledge may aid clinicians in the diagnosis and monitoring of the disease.  相似文献   
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