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61.
扩大经额硬膜外入路切除巨大侵袭性垂体瘤 总被引:1,自引:0,他引:1
目的:探讨采用扩大的经额硬膜外入路切除巨大侵袭性垂体瘤的临床应用.方法:1997年6月至2002年3月采用该入路显微外科切除巨大侵袭性垂体瘤10例,肿瘤主要累及于鞍上、蝶筛窦及上斜坡区.结果:本组10例中,肿瘤全切6例,次全切除3例,大部分切除1例.术后发生颅神经麻痹4例,其中动眼神经障碍3例,外展神经障碍1例.全组无手术死亡.术后影像学随访6~24个月,全切除肿瘤病例未见肿瘤复发,次全切除者无明显增大.结论:该入路可充分显露鞍区肿瘤,术野开阔,对脑组织损伤小,适用于已侵犯蝶筛窦区及上斜坡的侵袭性垂体瘤. 相似文献
62.
目的探讨血清腹水蛋白梯度(SAAG)在腹水定性诊断上的价值。方法选择2001~2004年收治的病因明确的152例腹水患者的血清及腹水标本,分为门脉高压性和非门脉高压性。腹水呈混合型表现有5例(肝硬化合并结核1例、肿瘤4例,其中合并肝癌3例)。腹水总蛋白(AFTP)≥25gL,腹水密度≥1.1018为渗出液,反之为漏出液。SAAG≥11gL诊断为门脉高压相关性腹水,SAAG<11gL为非门脉高压相关性腹水。结果以SAAG<11gL为诊断标准判断腹水为非门脉高压性的准确率为91.3%,而AFTP为62.2%,P<0.01;混合性腹水5例肝硬化合并结核或肿瘤患者(应属于门脉高压性腹水、渗出液),SAAG的诊断准确率为100%(55),而AFTP的诊断准确率为20%(15)。结论SAAG直接反映了门脉压,建议在腹水的定性分类中用SAAG取代既往的渗出-漏出系统。 相似文献
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65.
Michael D Seidman Mumtaz J Khan Wen Xue Tang Wayne S Quirk 《Otolaryngology--head and neck surgery》2002,127(3):138-144
OBJECTIVES: Lecithin is a polyunsaturated phosphatidylcholine (PPC), which are high energy functional and structural elements of all biologic membranes. PPC play a rate-limiting role in the activation of numerous membrane-located enzymes, including superoxide dismutase and glutathione, which are important antioxidants protecting cell membranes from damage by reactive oxygen species (ROS). ROS-induced damage to mitochondrial DNA may lead to reduced mitochondrial function in the cochlea and resultant hearing loss. STUDY DESIGN AND SETTING: The effects of lecithin on aging and age-associated hearing loss were studied in rats by measuring hearing sensitivities using auditory brainstem responses (ABR). In addition, mitochondrial function as a measure of aging was assessed by determining mitochondrial membrane potentials using flow cytometry and by amplifying mitochondrial DNA deletions associated with aging. Harlan-Fischer rats aged 18 to 20 months (n = 14) were divided into 2 groups. The experimental group was supplemented orally for 6 months with lecithin, a purified extract of soybean phospholipid (Nutritional Therapeutics, Allendale, NJ). RESULTS: The data obtained were compared with the control group. ABRs were recorded at 2-month intervals and showed significant preservation of hearing sensitivities in the treated subjects. Flow cytometry revealed significantly higher mitochondrial membrane potentials in the treated subjects, suggesting preserved mitochondrial function. Finally, the common aging mitochondrial DNA deletion (mtDNA(4834)) were amplified from brain and cochlear tissue including stria vascularis and auditory nerve. This specific deletion was found significantly less frequent in all tissues in the treated group compared with the controls. CONCLUSION: These experiments support our hypothesis and provide evidence that lecithin may preserve cochlear mitochondrial function and protect hearing loss associated with aging. 相似文献
66.
Glyceraldehyde-3-phosphate dehydrogenase: Nuclear translocation participates in neuronal and nonneuronal cell death
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Akira Sawa Adil A. Khan Lynda D. Hester Solomon H. Snyder 《Proceedings of the National Academy of Sciences of the United States of America》1997,94(21):11669-11674
Glyceraldehyde-3-phosphate dehydrogenase (GAPDH) protein levels increase in particulate fractions in association with cell death in HEK293 cells, S49 cells, primary thymocytes, PC12 cells, and primary cerebral cortical neuronal cultures. Subcellular fractionation and immunocytochemistry reveal that this increase primarily reflects nuclear translocation. Nuclear GAPDH is tightly bound, resisting extraction by DNase or salt treatment. Treating primary thymocytes, PC12 cells, and primary cortical neurons with antisense but not sense oligonucleotides to GAPDH prevents cell death. Because cell-death-associated nuclear translocation of GAPDH and antisense protection occur in multiple neuronal and nonneuronal systems, we propose that GAPDH is a general mediator of cell death and uses nuclear translocation as a signaling mechanism. 相似文献
67.
Computer-derived equations for predicting survival postoperatively. Their usefulness and limitations
E B Rypins F Khan D Collins-Irby I J Sarfeh J T Ashurst E A Stemmer 《Archives of surgery (Chicago, Ill. : 1960)》1988,123(3):354-357
We used multivariate analysis to determine whether survival following perforations of the gastrointestinal tract could be accurately predicted from preoperative data. Of 12 variables tested, four were found to have predictive value. These were age, pulmonary disease, preoperative shock, and the attending surgeon. When these four variables were employed in a logistic regression equation on 42 patients, it correctly predicted which 21 patients died before leaving the hospital. To produce an equation useful for other hospitals, we recalculated it without the attending surgeon variable. Again, the equation was used to predict survival. The correlation of predicted vs observed outcome remained high, and, using a 2 x 2 chi 2 test, the correlation was significant. We then cross validated the three-variable model on data from a second hospital. The model accurately predicted the new data equally well. We believe that predictive models can identify risk factors in a variety of patient populations and can determine who is likely to benefit from specific treatment modalities. 相似文献
68.
人脐血中血管内皮祖细胞体外扩增和鉴定的实验研究 总被引:7,自引:0,他引:7
目的:探讨从人脐血中分离、培养、体外扩增血管内皮祖细胞(EPC)的方法及体外进行EPC的鉴定。方法:采用密度梯度离心法从脐血中分离EPC,体外分别培养在包被有FN和不包被FN的培养皿中,采用免疫组织化学技术(SABC法)鉴定培养贴壁细胞表面标志CD31、CD34及KDR的表达;流式细胞仪检测细胞表面标志CD133及表达CD133细胞比例。结果:包被FN的培养皿中细胞贴壁及增殖均比未包被的多,免疫组化染色CD31、CD34及KDR均呈阳性,培养第4天流式细胞仪检测CD133^ 占21.3%。结论:密度梯度离心法可用于体外分离脐血中EPC进行实验研究,FN对于体外培养EPC有非常重要的作用。 相似文献
69.
Gall bladder hydatid cyst is a rare entity. Concurrent occurrence of gall blader hydatid cysts along with liver cysts, especially with the biliary channels clear of cysts, is very rare. We report a 27-year-old man with a gall bladder hydatid cyst that was diagnosed only after opening the resected specimen of the gall bladder. 相似文献
70.
腹腔镜下造口旁疝补片修补术可行性、安全性探讨 总被引:4,自引:2,他引:2
目的:就所开展的腹腔镜下造口旁疝补片修补术的临床资料,进行该手术可行性和安全性的探讨。方法:自2004年9月至2006年4月,我院为10例造口旁疝病人进行了腹腔镜下补片修补术。结果:10例造口旁疝病人中9例修补成功,1例因腹腔内广泛致密粘连而中转为开腹缝合修补;手术时间平均113(45~180)min:疝环大小平均5.6(4~6)cm;术后2例出现暂时性腹胀;7例修补区域腹壁疼痛,持续2周后均明显缓解:1例出现呼吸功能减退,经使用无创呼吸机辅助治疗后缓解;5例出现浆液肿,经2~4次穿刺抽液并加压包扎后治愈,无血肿发生.也未发生与手术相关的感染。术后住院时间平均5.7(3-9)d;术后随访平均9.1(2~19)个月,未见早期复发。结论:腹腔镜造口旁疝补片修补术从技术上讲是安全、可行的,从早期的临床结果来看.效果较理想。 相似文献