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991.
为了探讨肺类癌的临床特点、诊疗方法与预后的影响因素,对12例肺类癌病例进行回顾性研究。12例患者中2例伴有类癌综合征,2例术前经纤支镜确诊。术式包括肺叶切除9例,开胸探查1例,全肺切除2例,无手术期死亡和并发症。全组5年生存率为72.65%,类癌5年生存率为84.23%,不典型类癌为66.68%。初步研究结果提示,肺类癌属低度恶性肿瘤;影像学及纤维支气管镜检查对诊断具有重要价值;光镜HE染色常可诊断,但嗜银染色及电镜确定特征性嗜银性神经内分泌颗粒是确诊的可靠标准;治疗应以保守性外科手术切除为主,尽量保留肺功能为手术原则;手术切除后预后良好,远期疗效明显优于肺癌。 相似文献
992.
冠心病病人氧化修饰低密度脂蛋白的测定及临床意义 总被引:1,自引:0,他引:1
目的 :探讨氧化修饰低密度脂蛋白 (Ox LDL)对冠心病 (CHD)形成和发展的影响。方法 :CHD组 6 0例 ,对照组 5 3例。用酶标多克隆抗体夹心的方法检测血清Ox LDL含量。结果 :CHD组血清Ox LDL含量为 ( 48.6± 32 .8) μg dl。对照组( 2 5 .9± 2 2 .5 ) μg dl,两组之间Ox LDL含量存在显著性差异 (P <0 .0 0 1)。 结论 :Ox LDL和CHD有密切的关系 ,故可作为CHD病人特异性的辅助诊断指标。 相似文献
993.
大鼠骨髓间质干细胞体外分离培养及生物学特性研究 总被引:6,自引:5,他引:1
目的:建立大鼠骨髓间质干细胞(mesenchymal stem cells,MSCs)体外分离培养方法,并对大鼠MSCs的生物学特性进行研究。方法:分离5~8周龄的大鼠股骨骨髓进行体外培养,取5代以后的MSCs观察形态特征,绘制生长曲线,进行细胞化学染色,并用流式细胞仪检测其表面标志和进行细胞周期分析。结果:大鼠MSCs细胞形态呈长梭形或多边形,细胞生长曲线呈S形,群体倍增时间为30h,细胞化学染色显示碱性磷酸酶(ALP)、过氧化物酶(POX)、苏丹黑B(SB)阴性,而*醋酸萘酚醋酶(α-NAE)与糖原(PAS)阳性,流式细胞仪检测结果显示CD29、CD44、CD90表达阳性,而CD34、CD38、CD45表达阴性;细胞周期分析显示,G0/G1期:79.48%,G2/M期:6.10%,S期:14.42%。结论:本方法分离纯化出的是MSCs,其在体外具有生长稳定,增殖较快的特点,是组织工程研究中良好的细胞来源,也是转基因研究优良的载体细胞。 相似文献
994.
复方肾华治疗大鼠改良慢性血清病肾炎的实验研究 总被引:2,自引:0,他引:2
目的 观察复方肾华胶囊对改良大鼠慢性血清病肾炎模型的治疗作用。方法 采取传统大鼠慢性血清病肾炎模型制作方法加上切除大鼠一侧肾脏、隔日饮饲牛血清白蛋白 (BSA)酸化水、腹腔注射大肠杆菌内毒素 (LPS)等措施 ,制作肾炎模型 ,与西药蒙诺作对照 ,观察中药肾华对肾炎大鼠尿蛋白、血生化、凝血指标、肾功能、病理、免疫荧光以及增殖细胞核抗原 (PCNA)表达的作用。结果 肾华胶囊能够显著减轻肾炎大鼠肾脏重量及肾重指数、降低肾炎大鼠尿蛋白、升高血清蛋白、降低胆固醇、甘油三酯、改善肾功能、纠正凝血功能紊乱、减轻肾脏病理改变、减轻免疫荧光变化、减弱PCNA的表达。结论 中药肾华胶囊对大鼠慢性血清病肾炎模型有较好的治疗作用 相似文献
995.
S O Kim C T Lim S C Lam S E Hall D Komiotis D L Venton G C Le Breton 《Biochemical pharmacology》1992,43(2):313-322
The human platelet thromboxane A2/prostaglandin H2 receptor has been purified 6100-fold to apparent homogeneity by a three-step chromatographic procedure with an overall yield of 6%. A 6-fold purification of the receptor was first achieved by chromatography of 3-[(3-cholamidopropyl)dimethyl-ammonio]-1-propanesulfonate (CHAPS)-solubilized membrane proteins from human platelets on a diethylaminoethyl (DEAE)-Sepharose column. The DEAE eluate fractions containing receptor activity were then applied to a newly developed affinity column using the cyclohexyl derivative of SQ30,741 (SQ31,491) as the immobilized ligand. Elution of the receptor from the affinity column with BM13.177 yielded a further purification of 1700-fold. An additional 4-fold receptor purification from the affinity column eluate was achieved by HPLC using GPC 500 and GPC 100 columns connected in tandem. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis and silver staining of the HPLC eluate containing purified receptor revealed a single, distinct band with a molecular weight of 55,000. The receptor binding activity was detected with [3H]SQ29,548 using a newly developed binding assay which involved immobilization of the receptor on polyethyleneimine-treated glass fiber filters. The binding of [3H]SQ29,548 to the purified receptor was time dependent, saturable, reversible and highly specific. Unlabeled SQ29,548, BM13.505, and U46619 (but not thromboxane B2 or 6-keto prostaglandin F1 alpha) competed for [3H]SQ29,548 binding to the purified receptor in a concentration-dependent manner. Scatchard analysis of [3H]SQ29,548 binding to the purified receptor revealed the presence of a single class of high-affinity binding sites, with a Kd of 4 nM and a Bmax of 17 nmol/mg protein. 相似文献
996.
Sara Jo Nixon Austin L. Errico Oscar A. Parsons William R. Leber Cynthia J. Kelley 《Alcoholism, clinical and experimental research》1992,16(5):949-954
This study was conducted to determine whether alcoholic and control subjects respond differently to manipulations that either enhance personal involvement (PI) or reduce negative affect (R, relaxation) on tests of neuropsychological function. In Phase 1, 48 male alcoholics and 36 male control subjects completed neuropsychological tasks under standard instructional sets. In Phase 2, subjects completed equivalent forms of these tests under one of three randomly assigned conditions; the PI condition in which subjects were encouraged to identify specific ways of improving their performance, the R condition in which subjects participated in a short relaxation exercise designed to reduce anxiety, or a No Treatment (NT) condition in which no attempt to manipulate the subjects' involvement or affect was made. Alcoholics were inferior to controls in both Phase 1 and Phase 2 [Fs (1,82) > 5.03, ps < 0.03]. The experimental manipulation differentially affected measures of negative affect and effort in the predicted direction. There were no group x condition interactions. Alcoholic and control subjects responded comparably to the experimental manipulations. This investigation, in combination with others using related manipulations, reinforces the hypothesis that alcohol-related cognitives dysfunction reflects an underlying deficit in brain states. 相似文献
997.
William J Doyle Cuneyt M Alper Juliane M Banks J Douglas Swarts 《Otolaryngology--head and neck surgery》2003,128(5):732-741
OBJECTIVES: We tested the hypothesis that mastoid volume buffers the rate of change in middle ear pressure caused by transmucosal, inert gas exchange. STUDY DESIGN: Twelve monkeys were randomly assigned to group 1 or group 2. Right ears of group 1 had sham surgery and of group 2 had obstruction of the mastoid antrum. Before and after surgery, the time constant for transmucosal N(2)O exchange was estimated from N(2)O breathing experiments. The hypothesis predicts that the postoperative time constant measured for right ears of group 2 but not group 1 is greater than that measured before surgery. RESULTS: Mastoid antrum block significantly decreased right middle ear volume but did not affect the time constant for transmucosal N(2)O exchange. CONCLUSION: A mastoid gas-reserve function is not supported by the experimental data. SIGNIFICANCE: These results for monkeys and the theory developed to explain the effect of mastoid volume on transmucosal inert gas exchange suggest that the results for previous experiments in humans interpreted as evidencing a mastoid gas-reserve function are consistent with alternative explanations. 相似文献
998.
William L. Maxwell 《Clinical anatomy (New York, N.Y.)》1994,7(1):52-53
999.
组织工程颅骨缺损修复过程中超微结构观察 总被引:2,自引:0,他引:2
目的 用组织工程骨修复SD大鼠颅骨极量骨缺损,并在透射电镜下观察骨修复过程中成骨细胞、血管内皮细胞与陶瓷支架的关系。方法 14只雄性SD大鼠,随机分成实验组和对照组,每组7只。取左侧腔、股骨骨髓,体外诱导培养骨髓基质细胞。实验组将已分化的成骨细胞与含孔磷酸钙陶瓷复合用于修复大鼠自体颅骨极量骨缺损;对照组颅骨缺损处仅置入无细胞的陶瓷材料。分别于术后4、8、12、16、20、24及28周每组各处死1只动物取材,制成脱钙超薄切片,透射电镜下观察成骨细胞、血管内皮细胞与陶瓷残余支架的关系。结果 实验组动物颅骨修复12周前成骨细胞或成骨细胞样细胞毗邻新生小血管、血管内皮细胞存在,16周后成骨细胞转变为骨细胞,并围绕血管被包埋于骨基质及胶原纤维中;陶瓷残余与新生骨间有一条明显的钙化沉积带,大量胶原纤维已伸入到陶瓷支架的纳米级结构中。对照组陶瓷中央部位有大量小血管及血管内皮细胞增生,其周围多为幼稚成纤维细胞,无成骨细胞与血管内皮细胞的依附关系。结论 新型含孔磷酸钙陶瓷作为组织工程细胞支架,其间的纳米级结构有利于骨的再生和血管形成;未见来源于植骨床血管的内皮细胞衍变为成骨细胞。 相似文献
1000.
Drinking History Is Related to Persistent Blood Pressure Dysregulation in Postwithdrawal Alcoholics 总被引:1,自引:1,他引:0
Andrea C. King Oscar A. Parsons Nancy C. Bernardy William R. Lovallo 《Alcoholism, clinical and experimental research》1994,18(5):1172-1176
We have previously demonstrated that alcoholics with transitory (< 72 hr) elevations in blood pressure (BP) during withdrawal continue to show residual cardiovascular dysregulation up to 4 weeks of abstinence. The present study replicates and extends these findings. Alcoholic inpatients were divided into three subgroups ( ns = 14) based on BP during the first 72 hr of withdrawal: transitory hypertensives (tHTs; BP > 160/95 mm Hg), transitory borderline hypertensives (tBHs; 140/90 BP < 160/95), and normotensives (NTs; all BPs < 140/90). All patients had normal resting pressures after 72 hr of withdrawal. At 3–4 weeks postadmission, the alcoholics and 14 nonalcoholic controls (CONTs) were tested at rest and during a 5-min handgrip task. The tHTs showed an exaggerated systolic and diastolic BP response to handgrip compared with NTs and CONTs, with tBHs intermediate ( ps < 0.05). Drinking history showed the tHTs had the highest reported level of alcohol consumption and severity of withdrawal symptoms ( ps < 0.05). Regression analyses indicated that consumption of hard liquor was the variable most predictive of admission BPs; further, parental history of hypertension potentiated this relationship for systolic BP. Age and consumption of nicotine and caffeine were not significant predictors of admission BP. The results suggest a persistent cardiovascular dysregulation in alcoholics showing transient hypertensive withdrawal BPs. These alcoholics may be at increased risk for future alcohol-related cardiovascular disorder. 相似文献