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41.
李明秋  童荣原 《肿瘤》1995,15(6):435-437
作者对15例贲门癌患者行根治术同时,采用食管残胃间插入带蒂空肠并附加贲门再造术,通过SPECT胃食管返流指数测定、食管下端pH检测及返流症状评定方法,并与单纯食管胃套叠吻合术进行随机对比分析,证明该术式具有单向住屏障作用,能有效地预防返流性食管炎的发生。  相似文献   
42.
During liver transplantation for hepatocellular carcinoma (HCC) patients, HCC could theoretically be introduced into the systemic circulation when salvaged blood is used with an autotransfusion device. Several reports have shown that some types of leukocyte depletion filters (LDFs) could completely reduce the risk for reintroducing some types of tumor cells. In this study, we tested the ability of the LDF (RCEZ1T, Pall Biomedical Co, NY, USA) to reduce the risk for reintroducing HCC cells in vitro by using a very sensitive detection method. We divided the test group into 6 groups: group I was 10 cells, group II was 20 cells, group III was 2 x 10(3) cells, group IV was 2 x 10(5) cells, group V was 2 x 10(6) cells, and group VI was 2 x 10(7) cells. The counted cells in 200 mL saline were passed through the RCEZ1T using the force of gravity. To identify the presence of cells, the pellet was resuspended, and polymerase chain reaction (PCR) was performed. Glyceraldehyde-3-phosphate dehydrogenase (GAPDH), a housekeeping gene, was used as a primer. In groups I and II, the HCC cells were completely filtered in all experiments. However, in groups III, IV, and V, the HCC cells were not completely filtered in a few of the repeated experiments, with the unfiltered rate of tumor cells being between 8% and 20%. In group VI, the HCC cells were not completely filtered in all the repeated experiments. In conclusion, the RCEZ1T filter markedly reduced the risk for reintroduction of HCC cells. However, at high HCC cell load the filter cannot completely remove all the tumor cells. Further studies are required to assess the impact in clinical settings.  相似文献   
43.
观察了以内毒素作为致病原在支气管高反应性形成中的作用。结果:豚鼠腹腔注射内毒素后,其气道对组织胺引起哮喘潜伏期明显缩短,组织胺收缩离体气管平滑肌的PD2值明显增高,异丙肾上腺素松弛作用的PD2值显著降低,同时血浆及肺组织中组织胺含量显著增高。提示内毒素可能是呼吸道感染诱发支气管高反应性形成的重要因素,其机制与β受体功能改变及组织胺含量升高有关。  相似文献   
44.
自锁式防旋自动滑动加压钉板的研制与生物力学研究   总被引:1,自引:1,他引:0  
目的研制自锁式防旋自动滑动加压钉板(self—locking type pro-rotary auto-sliding&compression nail plate,LPSC—NP)用于股骨颈骨折内固定,对其进行生物力学性能测试,为临床应用提供依据。方法采集18具新鲜成年股骨近端标本,制成股骨颈骨折,分别用LPSC—NP、3枚空心钉、双头中空加压螺纹钉、动力髋螺钉内固定,并进行生物力学测试,用SPSS统计软件对实验数据进行分析。结果LPSC—NP的承载能力和抗扭转强度、刚度均明显大于后三者。结论LPSC—NP固定股骨颈骨折牢固可靠,符合生物力学要求。该器械结构合理,简单适用,有一定的临床价值。  相似文献   
45.
Purpose: The aim of the study was to provide information about the characteristics of three main types of orthokeratology (ortho‐k) lenses used in Hong Kong and to report on their performance based on the clinical impressions of a group of ortho‐k practitioners. Method: Twelve ortho‐k practitioners were interviewed between 1 March and 30 June 2001. Results: Most ortho‐k lenses were ordered from three manufacturers: DreimLens, Fargo and Contex. The median maximum myopia reduction reported for DreimLens, Contex and Fargo lenses were 6.25 D, 6.00 D and 4.50 D respectively. The time to reduce myopia by up to 4.00 D could be up to three weeks for Contex and DreimLens and up to four weeks for Fargo. For reduction of myopia by up to 4.00 D, the treatment usually required only one or two lenses per eye for all three types of lenses. The incidence of lens binding and lens tightening after achieving the optimal reduction was reported to be higher with the DreimLens design. Good centration, less lens binding, relatively lower incidence of complications and lens tightening after achieving the optimal reduction were reported with the Fargo lenses. Conclusions: DreimLens tended to be more effective for myopia reduction. However, some practitioners were concerned with the aggressiveness of myopia reduction using this lens design and the higher potential for ocular complications. Selection of the lens design is dependent on various factors, in particular, practitioners need to be comfortable with the design they choose and to consider the needs of their patients and the final goal of the treatment.  相似文献   
46.
探讨人的增强子结合蛋白(C/EBP)相关基因。方法以大鼠C/EBPcDNA为探针,筛选人胎盘cDNA文库。结果得到一个含有1975碱基命名为HP8的cDNA克隆,其中1~604位碱基属编码区。经基因数据库查对未发现同源基因。该基因编码的蛋白C-末端含有亮氨酸拉链结构(leucine zipper struceure)和C/EBP功能区(C-末端60个氨基酸)同源性高达97%,而上游编码区则与C/EBP及其已知家族同源性很低,表明该基因属C/EBP基因家族新成员。基因组Southern杂交证实该基因为单拷贝基因。在14种胎儿组织中显示小肠、皮肤高表达,肾上腺中度表达,肝、肺、肾、甲状腺、胆囊低表达。在3例正常成人肝组织中仅1例低表达,而在5对肝癌及癌旁肝组织中显示2例癌组织及1例癌旁组织高表达。结论以上结果提示该基因可能与细胞增殖有关。  相似文献   
47.
为开展脐门静脉造影的介入放射学,弥补肝动脉化疗的不足,探讨肝脏内恶性肿瘤化疗的新途径。本文对8例男性肝脏左叶占位性病变患者作脐静脉穿刺造影测得肝圆韧带内脐静脉自肝门静脉左支囊都至腹壁脐切迹全长为19.4±4.3 cm。讨论了脐门静脉造影的优点及其临床意义。  相似文献   
48.
49.
云南省卫生资源配置标准的弹性系数研究   总被引:2,自引:1,他引:1  
目的 在进行云南省区域分类基础上制定云南省区域卫生资源配置标准标志值后 ,根据云南省各个地区的特点增加不同弹性系数。方法 采用流行病学研究方法 ,收集和分析云南省不同地州市 1990~ 1999年有关人口、社会经济状况及卫生经费的投入、居民健康状况、居民文化、生活水平、少数民族状况、旅游地区、边境线长短及贫困状况等资料。结果 研究结果表明曲靖地区、玉溪市、保山地区增加弹性系数最少 ,分别为 0 67%、 1 5 8%和1 68% ,怒江州、迪庆州和西双版纳州增加弹性系数最多 ,分别为 11 15 %、 10 2 5 %和 9 84 %。其它地区的弹性系数分别为昆明市 5 88% ,昭通地区 2 3 1% ,楚雄州 2 3 0 % ,红河州 7 0 3 % ,文山州 5 5 3 % ,思茅地区 7 4 3 % ,大理州4 94 % ,德宏州 6 78% ,丽江地区 4 3 5 % ,临沧地区 6 13 %。结论 云南省区域卫生配置标准的弹性系数研究为云南省卫生资源区域分类配置标准提供了科学依据 ,不同弹性系数体现了云南省不同地区的卫生资源区域分类配置标准的公平性、合理性及实用性  相似文献   
50.
A 12-year-old girl with a history of fast myopia progression underwent advanced orthokeratology (ortho-k) treatment and suffered from recurrent lens binding and central corneal staining. The problem could not be fixed by lens fenestration and refitting with a less aggressive lens (three-zone ortho-k) design. After refitting with a lower target advanced ortho-k lens, these complications were no longer occurring, and the amount of power reduction was greater than expected considering the target designed for the refitted lenses. During the following 15 months of ortho-k lens wear, there was no clinically significant change to her refractive error. The patient and her parents were happy with the outcome, although the refractive error was not totally eliminated and she still needed to wear spectacles for clear vision. Possible etiologies of the complications are discussed.  相似文献   
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