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131.
目的 观察巯基化合物对内毒素诱导大鼠枯否细胞(KC)NF-kB活性和肿瘤坏死因子-a(TNF-a)释放的影响。方法采用胶原酶灌注和percoll密度梯度离心法分离得到高纯度大鼠KC,在过夜培养后冲洗两遍(不含血清),加入内毒素(LPS)10ng/ml刺激原代培养的KC,观察不同浓度谷胱甘肽乙基酯(GSHEE)及N-乙酰半胱氨酸(NAC)对大鼠KCTNF-a释放和KC内谷胱甘肽(GSH)及NF-kB活性的影响。并观察使用谷胱甘肽合成抑制剂BSO后,对NAC抑制炎症因子的影响,采用凝胶滞留电泳法测NF-kB活性,采用高效液相色谱分析法测GSH水平。结果 LPS诱导KC中GSH水平无变化;GSHEE和NAC可提高KC中GSH水平(P〈0.05),降低NF-kB活性和TNF-a释放(P〈0.05)。NAC与BSO合用时KC中GSH水平无变化,TNF-a释放降低(P〈0.05)。结论 NAC通过抑制KC中NF-kB的激活和TNF-a的释放调节KC功能,但这种抑制作用并非通过增加GSH介导。 相似文献
132.
IIEF-5与NEVA检测在阴茎勃起功能障碍诊断中的意义 总被引:2,自引:2,他引:0
目的探讨应用国际勃起功能评分5(IIEF-5)问卷表结合夜间阴茎勃起测定系统(NEVA)筛选勃起功能障碍(ED)的可行性及意义。方法148例门诊ED病人,应用IIEF-5问卷表评分,再通过NEVA测定仪监测夜间阴茎勃起情况,次日数据输入主机回放并分析。结果93例为心理性ED;在19~69岁的5个年龄组中,重度ED的比例由11.8%到55.0%,NEVA中度异常者IIEF积分(12.98±2.58)分,NEVA重度异常者IIEF积分(7.32±1.04)分。结论NEVA能有效地鉴别心理性与器质性ED,IIEF-5评分值与NEVA检测阴茎勃起时血容量变化值有相关性。IIEF-5与NEVA检测结合,能提高诊断和评估ED的可靠性。 相似文献
133.
C.A. AMEZCUA H.R. MACDONALD† C.A. LUM W. YI‡ L.I. MUDERSPACH† L.D. ROMAN† & J.C. FELIX† 《International journal of gynecological cancer》2006,16(3):1336-1341
In this study, we examine the prevalence of finding isolated tumor cells (ITCs) in negative lymph nodes of endometrial cancer patients using immunohistochemistry. Seventy-six endometrial cancer patients with lymph nodes histologically negative for metastatic disease were examined. Nodal tissue sections were stained with anticytokeratin antibodies AE-1 and CAM 5.2. Nodes with single or groups of cells (two to four cells) < or =0.2 mm and showing cytokeratin reactivity were positive for ITCs. Findings were compared to features of the primary tumor and patient outcome. ITCs were present in 31 of 1712 lymph nodes. Fifteen (19.7%) patients had ITC-positive nodes. ITCs involved only pelvic nodes in nine cases, only para-aortic nodes in five cases, and pelvic and para-aortic in one case. Tumor in adnexa was the only pathologic feature associated with nodal ITCs (P= 0.0485). All 15 patients with nodal ITCs were alive at follow-up. One (6.7%) patient suffered recurrent disease but was alive at last encounter. Disease recurred in 5 (8.8%) of 57 patients without nodal ITCs. Two are alive without disease, two alive with disease, and one died from her cancer. In summary, a significant proportion of endometrial cancer patients have ITCs detected by immunohistochemistry in histologically negative regional lymph nodes. 相似文献
134.
庆大霉素对豚鼠前庭上皮IGF-1及其受体表达的影响 总被引:1,自引:0,他引:1
目的:研究庆大霉素对豚鼠前庭上皮胰岛素样生长因子-1(insulin-like growth factor-1,IGF-1)及其受体(insulin-like growth factor-1 receptor,EGF-1R)表达的影响,并探讨其生物学特性。方法:采用免疫组织细胞化学方法,以抗IGF-1及IGF-1R抗体为标记物,检测庆大霉素损伤后豚鼠前庭上皮自发修复期IGF-1及IGF-1R的表达变化和分布特点;采用Brdu体内标记和抗Brdu抗体免疫组化染色,检测庆大霉素损伤后豚鼠前庭上皮增殖的变化。结果:IGF-1及IGF-1R在正常成年豚鼠前庭上皮细胞中有低水平表达,庆大霉素损伤后,其表达增多。在1d组IGF-1及IGF-1R表达最强,其后逐渐减少。在正常对照组中无Brdu阳性细胞。各实验组均观察到Brdu阳性细胞,7d组最多。结论:庆大霉素损伤后,豚鼠前庭上皮IGF-1及IGF-1R表达增强,其时程变化与细胞增殖活动密切相关。IGF-1在豚鼠前庭上皮损伤后的细胞增殖中可能起重要信号转导作用。 相似文献
135.
鸡抗内毒素卵黄抗体IgY的制备 总被引:2,自引:1,他引:1
目的:研究分别应用内毒素(LPS)、类脂A(LipidA)和大肠杆菌突变株15免疫鸡后其蛋黄中抗内毒素抗体IgY的产量、纯度、效价并筛选最佳免疫抗原。方法:分别应用内毒素(LPS)、类脂A(LipidA)和大肠杆菌J5突变株作为抗原免疫25周龄Leghom鸡,水溶法(WD)提取蛋黄中抗体IgY,双紫外光测定抗体含量,SDS-PSGE电泳检测抗体纯度,细胞酶联染色和ELISA检测抗体特异性、效价及筛选最佳免疫抗原。结果:3种抗内毒素IgY含量和效价分别为14.4mg/ml和1:12 800(J5)、10.61mg/ml和1:12 800(LPS)、9.26mg/ml和1:3200(LipidA),抗体纯度均为95%左右。结论:大肠杆菌突变株J5和内毒素(LPS)为最佳免疫抗原,免疫鸡后其蛋黄中抗内毒素抗体IgY的产量和效价最高。 相似文献
136.
目的:观察离体心脏左心室三层心肌的单相动作电位的改变,以探讨扩张型心肌病易发心室颤动与三层心肌跨室壁复极不均一性的关系。方法:用阿霉素制作扩张型心肌病家兔模型,测定其室颤阈值(VFT)以及心外膜、中层心肌和心内膜心肌细胞的单相动作电位复极90%时程(APD90)、跨室壁复极离散度(TDR)。结果:扩张型心肌病VFT明显降低(P<0.001),三层心肌细胞APD90均明显延长(P<0.001),中层心肌细胞较心外膜、心内膜下心肌细胞延长更为显著(P<0.05);扩张型心肌病跨室壁复极离散度增加(P<0.01)。结论:中层心肌细胞APD90明显延长、跨室壁复极离散度增加、三层心肌复极不均一性增加可能是扩张型心肌病容易发生心室颤动的重要原因。 相似文献
137.
Cytologic evaluation of the CSF is often difficult when trying to distinguish between truly neoplastic and reactive cells. Several non-neoplastic conditions may be associated with atypical cells in the CSF, a fact the clinician has to consider to avoid inadequate aggressive theraphies. We report here three patients with infectious meningitis (due to Herpes zoster virus in two, and neuroborreliosis in one) and cytologically atypical cerebrospinal fluid lymphocytes. Further characterization showed that the pleocyrosis in these patients was of reactive origin. Cytomorphology is frequently insufficient and histochemical, immuncytochemical and cellular genome analysis techniques may help differentiate atypical reactive cells from neoplastic cells. 相似文献
138.
氟苯咪唑(Fludendazole)由Gelder于1969年合成,直到最近几年才受到各国重视,我国于1983年也合成了该化合物。该药经临床应用疗效显著,抗虫效力高,抗虫谱 相似文献
139.
J. Kralovanszky N. Prajda S. Kerpel-Fronius T. Bagrij E. Kiss G. J. Peters 《Cancer chemotherapy and pharmacology》1993,32(3):243-248
Selective protection of the normal host tissues from the toxic effects of anticancer agents would allow the use of higher, probably more effective, doses of the drugs. It has been demonstrated that delayed high-dose uridine administration after 5-fluorouracil decreases the extent of myelosuppression and causes faster regeneration of the bone marrow. We studied the biochemical consequences of the gastrointestinal toxicity caused by 5-fluorouracil and the potential of high-dose uridine treatment to influence these adverse effects. 5-Fluorouracil caused dose-related decreases in the biochemical parameters (thymidine kinase, sucrase, maltase, alkaline phosphatase) selected as early markers of the impaired metabolic activity of the intestinal mucosa. The nadir of the biochemical changes was reached between 24 h and 72 h after 5-fluorouracil treatment, and complete regeneration of the mucosa took 6–7 days. Delayed high-dose uridine administration failed to mitigate the severity of the gastrointestinal damage that ensued after 5-fluorouracil treatment, but caused significantly earlier regeneration of the mucosa. 相似文献
140.
B. A. Johnson Donald R. Jasinski Gantt P. Galloway Henry Kranzler Robert Weinreib Raymond F. Anton Barbara J. Mason Michael J. Bohn Helen M. Pettinati Richard Rawson Christopher Clyde 《Psychopharmacology》1996,128(2):206-215
Four hundred and twenty-three alcohol dependent subjects were enrolled into a 12-week randomized, double-blind, placebo-controlled
study to determine the safety and efficacy of the 5-HT2 receptor antagonist, ritanserin (2.5 mg/day or 5 mg/day), in reducing alcohol intake and craving. All subjects received 1
week of single-blind placebo prior to randomization into the 11-week double-blind phase. Additionally, all subjects received
weekly individual sessions of manual-guided cognitive-behavioral therapy. Comparing the single-blind period with endpoint,
there was approximately a 23% reduction in drinks/day; 34% fall in the total number of drinking days/week; 22% decrease in
drinks/drinking day; and a 37% diminution in alcohol craving for all treatment groups. All treatment groups experienced a
beneficial clinical outcome as assessed by the Clinical Global Impression Scale. There was, however, no significant difference
between treatment groups on any of these measures of alcohol drinking, craving, or clinical outcome. Subjects were of relatively
high social functioning at baseline, and this did not change significantly during treatment. Treatment groups did not differ
significantly on either medication compliance or reported adverse events. Ritanserin treatment was associated with a dose-related
prolongation of subjects’ QTc interval recording on the electrocardiogram. These results suggest that alcohol dependent subjects
can show marked clinical improvement within a structured alcohol treatment program. These findings do not support an important
role for ritanserin in the treatment of alcohol dependence.
Received: 30 April 1996/Final version: 3 July 1996 相似文献