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11.
推广规范化的胃癌淋巴结清扫术   总被引:5,自引:1,他引:4  
胃癌外科治疗的历史始自Billroth1881年在维也纳为胃癌患者成功施行世界上第1例胃切除,距今已近120a.本世纪初,胃癌是癌肿的头号杀手(theleadingcancerkiller).最近几十年,全球的胃癌病死率有所下降,但我国农村幅员广阔,农村人口比例高,目前胃癌的病死率仍居各种肿瘤的首位.最近20a~30a,以日本为代表的胃癌的外科治疗已经获得长足的进步.我国胃癌的外科诊治水平也有明显的提高[1],根治性切除率、早期胃癌比率以及5年生存率均有明显提高,手术死亡率及并发症发生率明显下降…  相似文献   
12.
目的:分析不同载荷对C4~5椎间孔孔径变化的影响。方法:实验于2006-01/2006-05在湘南学院附属医院进行。成人新鲜尸体颈椎标本10具(自愿捐献或家属同意),节段包括C3~T1,剔除肌肉组织,保留椎间盘、韧带和关节囊结构的完整。分别测量椎间盘完整、椎间盘髓核摘除、颈人工椎间盘置换和前路钢板植骨内固定4种状态下,加压速度为5mm/min时,25,50,75,100,125和150N的分级轴向载荷加载于标本时C4~5上下径、上前后径、下前后径以及椎间孔面积的变化。结果:①轴向加载25N时,C4~5椎间孔面积椎间盘髓核摘除标本小于完整椎间盘、颈人工椎间盘置换和前路钢板植骨内固定标本[(57.26±17.65),(65.81±16.83),(75.37±17.75),(66.21±16.50)mm2,P<0.05];颈人工椎间盘置换标本大于颈椎植骨融合钢板内固定标本(P<0.05)。②轴向加载50N时,C4~5椎间孔面积椎间盘髓核摘除标本小于其他3组[(57.13±17.64),(65.72±16.85),(75.35±17.75),(66.11±16.46)mm2,P<0.05];颈人工椎间盘置换标本大于颈椎植骨融合钢板内固定标本(P<0.05)。③轴向加载75N时,上下径:C4~5椎间孔面积椎间盘髓核摘除标本小于其他3组[(55.26±17.66),(64.80±16.85),(73.32±17.74),(65.21±16.48)mm2,P<0.05];颈人工椎间盘置换标本大于颈椎植骨融合钢板内固定标本(P<0.05)。④轴向加载100N时,上下径:C4~5椎间孔面积椎间盘髓核摘除标本小于其他3组[(53.22±17.66),(63.81±16.83),(71.35±17.76),(65.27±16.46)mm2,P<0.05]。⑤轴向加载125N时,C4~5椎间孔面积椎间盘髓核摘除标本小于其他3组[(51.25±17.64),(62.82±16.83),(69.25±17.74),(65.25±16.43)mm2,P<0.05]。⑥椎间孔面积:轴向加载150N时,C4~5椎间孔面积椎间盘髓核摘除标本小于其他3组[(49.16±17.65),(61.84±16.86),(67.15±17.73),(65.24±16.42)mm2,P<0.05]结论:颈椎间盘髓核摘除后C4~5椎间孔有效空间明显减少。  相似文献   
13.
人羊膜间充质细胞具有分化成软骨及成骨细胞的潜能   总被引:1,自引:0,他引:1  
目的:人羊膜间充质细胞具有比骨髓间充质干细胞更强的扩增能力和免疫原性低等优势。建立体外适宜的诱导培养条件,观察人羊膜间充质细胞定向分化为软骨细胞和成骨细胞的能力。方法:实验于2005-09/2006-12在贵州省细胞工程重点实验室完成。①材料来源:经产妇知情同意,无菌采集健康足月分娩新生儿胎盘6份,实验经医院医学伦理委员会批准。②实验方法:采用机械法剥离羊膜组织,二步酶消化法分离收获人羊膜间充质细胞,按2.2×10~8L~(-1)密度接种,传至第1~2代用于诱导分化实验。向软骨细胞诱导分化时,人羊膜间充质细胞按3×10~8L~(-1)密度接种,诱导培养液为含体积分数0.01的胎牛血清、10 mg/L转化生长因β1、100 nmol/L地塞米松、50 mg/L抗坏血酸、1%培养基添加物。向成骨细胞诱导分化时,人羊膜间充质细胞按6×10~7L~(-1)密度接种,诱导培养液为含体积分数0.1的胎牛血清、100 nmol/L地塞米松、50 mg/L抗坏血酸、5 mmol/Lβ-甘油磷酸。③实验评估:原代细胞用流式细胞仪分析表型,免疫细胞化学染色进行波形蛋白表达鉴定。分别于体外诱导第7,14,21,28天采用免疫细胞化学法检测软骨特异性Ⅱ型胶原的表达,细胞化学法检测蛋白聚糖的表达,钙-钴法检测成骨细胞特异性碱性磷酸酶的表达,茜素红S检测钙盐沉积情况。结果:①免疫组化与表型特征:人羊膜间充质细胞高表达间充质干细胞表面标志CD29、CD44和间充质细胞标志波形蛋白。②向软骨细胞诱导分化:诱导14 d后,人羊膜间充质细胞由长梭型逐渐变为多角形,可检测到Ⅱ型胶原蛋白表达及软骨细胞特异性细胞外基质蛋白聚糖。③向成骨细胞诱导分化:诱导21 d后,可观察到人羊膜间充质细胞的胞浆内有碱性磷酸酶表达,且可见钙盐沉积。结论:人羊膜间充质细胞具有分化成软骨细胞和成骨细胞的特性,可作为骨及软骨组织工程种子细胞的新来源。  相似文献   
14.
Splenectomy in myeloid metaplasia   总被引:3,自引:0,他引:3  
Silverstein  MN; ReMine  WH 《Blood》1979,53(3):515-518
Between 1960 and 1977, 50 patients with agnogenic myeloid metaplasia were splenectomized. Twenty-five of 26 patients with painful splenomegaly, 4 of 9 patients with refractory hemolytic anemia, 4 of 10 patients with refractory thrombocytopenia, and 4 of 4 patients with portal hypertension showed significant benefit from the procedure. There were five immediate postoperative deaths. Four of these deaths occurred early in our series of splectomies for myeloid metaplasia before 1970. Only one death has occurred in the last 21 patients operated on. Survival following splenectomy averaged 25.5 mo.  相似文献   
15.
AIM: To evaluate existing evidence for the association between different type of brassiere exposures and the risk of breast cancer. METHODS: Ovid Medline, CINAHL, Cochrane Data Base of Systematic Reviews, Pubmed, Scopus, Proquest, Sciencedirect, Wiley Online Library, WanFang Data, Hong Kong Index to Chinese Periodicals, China Journal Net, Chinese Medical Current Contents, Chinese Biomedical Literature Database, China Academic Journals Full-Text database, Taiwan Electronic Periodical Services and HyRead; reference lists of published studies; original research studies published in English or Chinese examining the association between type and duration of brassiere-wearing and breast cancer risk. Data were abstracted by a first reviewer and verified by a second. Study quality was rated according to predefined criteria. “Fair” or “good” quality studies were included. Results were summarised by meta-analysis whenever adequate material was available. RESULTS: Twelve case-control studies were included in the review. Meta-analysis showed brassiere wearing during sleep was associated with a two times of increased odds. CONCLUSION: The present review demonstrates insufficient evidence to establish a positive association between the duration and type of brassiere wearing and breast cancer. Further research is essential; specifically, a large-scale epidemiological study of a better design is needed to examine the association between various forms of brassiere exposure in detail and breast cancer risk, with adequate control of confounding variables.  相似文献   
16.
Radiation-induced red cell damage: role of reactive oxygen species   总被引:1,自引:1,他引:1  
BACKGROUND: Cellular blood components are irradiated to prevent graft- versus-host disease in transfusion recipients at risk for this syndrome. Because gamma radiation can result in the production of reactive oxygen species, the role of reactive oxygen species was investigated in radiation-induced red cell damage. STUDY DESIGN AND METHODS: Whole blood from normal donors was exposed to various doses of t-butyl hydroperoxide (0-1 mM) and/or to gamma-radiation (0-50 Gy). Oxidative damage was assessed by the extent of lipid peroxidation (measured by thiobarbituric acid-reactive substances [TBARS]) and hemoglobin oxidation. Fresh blood was divided into three parts-one initially irradiated and stored, another stored with portions irradiated weekly, and a third stored without irradiation. TBARS and hemoglobin oxidation were measured weekly. RESULTS: As expected, t- butyl hydroperoxide induced TBARS formation and hemoglobin oxidation in a dose-dependent fashion. The gamma-radiation not only increased hemoglobin oxidation and TBARS formation, but also enhanced the t-butyl hydroperoxide effect on red cells. Red cell storage increased TBARS generation and hemoglobin oxidation in a time-dependent fashion. When radiation was administered either initially or after weekly storage, TBARS production and hemoglobin oxidation were increased over that measured in unirradiated paired controls. CONCLUSION: Gamma radiation at clinically used doses increases lipid peroxidation and hemoglobin oxidation in human red cells. The effect of gamma-radiation is accentuated by blood storage and induces damage independent of time of storage.  相似文献   
17.
18.
WH Visser  MD  ; RHM de  Vriend  MSc ; NHWM Jaspers  MSc  ; MD Ferrari  MD  PhD 《Headache》1996,36(8):471-475
Sumatriptan, notably after subcutaneous administration, is highly effective in the acute treatment of migraine in the majority of patients. The response is consistent within patients and over time. To determine risk factors for nonresponse to sumatriptan, we compared clinical characteristics. In responders and nonresponders and, within patients, between attacks with and without response. We found no differences at the strict level of significance (P<0.001 because of multiple comparisons), but only tendencies for differences (0.001相似文献   
19.
Background Heart failure (HF) is a physically and socially debilitating disease that carries the burden of hospital re-admission and mortality. As an aging society, Hong Kong urgently needs to find ways to reduce the hospital readmission of HF patients. This study evaluates the effects of a nurse-led HF clinic on the hospital readmission and mortality rates among older HF patients in Hong Kong. Methods This study is a retrospective data analysis that compares HF patient in a nurse-led HF clinic in Hong Kong compared with HF patients who did not attend the clinic. The nurses of this clinic provide education on lifestyle modification and symptom monitoring, as well as titrate the medications and measure biochemical markers by following established protocols. This analysis used the socio-demographic and clinical data of HF patients who were aged ≥ 65 years old and stayed in the clinic over a six-month period. Results The data of a total of 78 HF patients were included in this data analysis. The mean age of the patients was 77.38 ± 6.80 years. Approximately half of the HF patients were male (51.3%), almost half were smokers (46.2%), and the majority received ≤ six years of formal education. Most of the HF patients (87.2%) belonged to classes II and III of the New York Heart Association Functional Classification, with a mean ejection fraction of 47.15 ± 20.31 mL. The HF patients who attended the clinic (n = 38, 75.13 ± 5.89 yrs) were significantly younger than those who did not attend the clinic (n = 40, 79.53 ± 6.96 yrs) (P = 0.04), and had lower recorded blood pressure. No other statistically significant difference existed between the socio-demographic and clinical characteristics of the two groups. The HF patients who did not attend the nurse-led HF clinic demonstrated a significantly higher risk of hospital readmission [odd ratio (OR): 7.40; P < 0.01] than those who attended after adjusting for the effect of age and blood pressure. In addition, HF patients who attended the clinic had lower mortality (n = 4) than those who did not attend (n = 14). However, such a difference did not reach statistical significance when the effects of age and blood pressure were adjusted. A significant reduction in systolic blood pressure [F (2, 94) = 3.39, P = 0.04] and diastolic blood pressure [F (2, 94) = 8.48, P < 0.01] was observed among the HF patients who attended the clinic during the six-month period. Conclusions The finding of this study suggests the important role of nurse-led HF clinics in reducing healthcare burden and improving patient outcomes among HF patients in Hong Kong.  相似文献   
20.
目的:对比观察骨髓间充质干细胞移植前后脑梗死大鼠脑电图的变化。方法:实验于2002-09/12在解放军第三军医大学中心实验室及西南医院神经内科肌电图室完成。①实验分组:选取清洁级健康成年Wistar大鼠15只,随机数字表法分为干细胞移植组、模型对照组、假手术组,5只/组。②实验方法:另取2只健康幼年Wistar大鼠用于骨髓间充质干细胞的提取,联合采用密度梯度离心及贴壁法分离培养大鼠骨髓间充质干细胞,选取生长良好的1~3代细胞用于移植实验。干细胞移植组、模型对照组大鼠建立大脑中动脉栓塞模型。假手术组仅分离颈总动脉、颈外动脉和颈内动脉,不予结扎和放置线栓。造模后1周,干细胞移植组、假手术组大鼠行细胞移植,在立体定向仪定位下于脑梗死区(壳核)直接注射骨髓间充质干细胞悬液5μL,细胞浓度1×104μL-1,移植坐标为前囟前1.0mm,右旁开3.0mm,硬膜下5.0mm。模型对照组大鼠于相同部位注射等量不含细胞的磷酸盐缓冲液。③实验评估:采用脑电图机分别于造模前、造模后1周(移植前)、细胞移植后4周对各组大鼠进行脑电图检测。结果:15只大鼠均进入结果分析。①造模前基本节律为8~11Hz、15~30μV的α波,间或少量θ波,双侧对称。②造模后1周,假手术组异常率为0;模型对照组20%(1/5)轻度异常,80%(4/5)中度异常;干细胞移植组20%(1/5)轻度异常,60%(3/5)中度异常,20%(1/5)重度异常。③细胞移植后4周,假手术组脑电图恢复正常;模型对照组随术后时间的延长慢波有所减少,但仍可见到δ波、棘波、棘慢波的发放,至细胞移植后4周60%(3/5)轻度异常,40%(2/5)中度异常;干细胞移植组术后局限性慢波逐渐减少,基本节律全部恢复为α波,不对称的情况明显好转,至细胞移植后4周60%(3/5)轻度异常,以病灶侧局限性θ波较多为主,另外40%(2/5)基本正常。结论:动物实验显示骨髓间充质干细胞移植对脑梗死大鼠的脑电图背景节律有改善作用,一定程度上促进了神经系统功能的恢复。  相似文献   
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