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101.
目的 :为了开发西洋参在临床医学方面的应用 ,提高CPHD病人的各项免疫指标。方法 :选择 4 0例CPHD病人 ,分成用药组 2 0例 ,对照组 (非用药组 ) 2 0例 ,通过流式细胞术检测病人外周血中T淋巴细胞亚群中各亚群所占的比例来反映机体的细胞免疫状态。结果 :通过两组临床研究观察 ,用药组疗效优于对照组 (P <0 0 5 )。西洋参茎叶皂甙可直接作用于淋巴细胞分化成熟过程 ,具有增强和调节CPHD病人机体免疫功能的作用。结论 :合理应用西洋参茎叶茎叶皂甙对改善CPHD病人免疫功能低下和紊乱状态 ,具有重要临床意义。  相似文献   
102.
A newly developed severe acute respiratory syndrome (SARS)-specific enzyme-linked immunosorbent assay (ELISA) was further validated to confirm cutoff values and evaluate its diagnostic performance with clinical samples. In parallel, an immunochromatographic test was also evaluated. A total of 227 clinical serum specimens collected from SARS patients were used in the study, together with 385 samples from healthy donors. By use of an immunofluorescent (IF) test as the “gold standard, ” both the ELISA and the immunochromatographic test were able to detect immunoglobulin G antibodies to SARS not only from late-convalescent-stage samples (>21 days from the onset of clinical symptoms), as previously established, but also from early-acute-phase samples (1 to 10 days from onset). The ELISA, using an optical density (OD) of 0.25 as its cutoff value, produced the best sensitivity while maintaining high specificity. It detected SARS-specific antibodies in 58, 70, 75, and 95%, respectively, of the four groups of samples collected from patients 1 to 10 days, 11 to 20 days, 21 to 30 days, and more than 30 days after the onset of clinical symptoms. Similarly, the immunochromatographic test detected SARS-specific antibodies in 55, 68, 81, and 79% of the four groups, respectively. The overall specificities for the ELISA and the rapid test were 99.5 and 97.7%, respectively. Although the positive correlation observed between the ELISA OD values and the IF titers was moderate (r = 0.6915; P < 0.001), the detection rates of both the ELISA and the rapid test were found well in agreement with the IF titers.  相似文献   
103.
Adhesion of yeasts and bacteria to silicone rubber is one of the first steps in the biodeterioration of indwelling, silicone rubber voice prostheses. In this paper, silicone rubber, so-called "Groningen button," voice prostheses were treated with a colloidal palladium/tin solution to form a thin metal coat intended to discourage biofilm formation. First it was demonstrated that this treatment did not negatively affect the airflow resistance of the prostheses or induce any cytotoxicity. Subsequently, palladium/tin-treated voice prostheses were placed in a modified Robbins device together with untreated control prostheses to evaluate biofilm formation. Biofilms were formed by inoculating the device for 3 days with the total cultivable microflora obtained from an explanted, malfunctioning voice prosthesis supplemented with separately isolated yeasts (Candida albicans and Candida tropicalis). After 3 days the device was perfused three times daily with growth medium and phosphate-buffered saline. The device was allowed to drain between perfusions to better mimic the conditions in the oropharynx (moist but not always fully wetted). After 9 days the total number of bacterial and fungal colony-forming units on the prostheses were determined microbiologically, and scanning electron micrographs were taken of the valve sides. Biofilm formation was significantly less on the heavily treated palladium/tin prostheses than it was on the untreated prostheses although some ingrowing microcolonies also were observed on the treated prostheses. The spread of the biofilms was smaller on the treated prostheses than on the untreated ones.  相似文献   
104.
105.
广东汉族人β2-肾上腺素能受体基因Gln27Glu多态性   总被引:2,自引:0,他引:2  
目的 探讨β2-AR 16位点基因多态性在广东汉族人群中的分布.方法 应用聚合酶链反应技术对122例正常人β2-肾上腺素能受体基因Gln27Glu进行扩增并进行图谱分析.并结合文献进行了不同种族间的分析比较.结果 广东汉族人群β2-AR基因27位点多态性分布频率:Gln/Gln基因型占36.88%,Gln/Glu基因型占52.46%,Glu/Glu基因型占10.66%.结论 广东汉族人群存在出β2-AR Gln27Glu基因多态性,其分布频率与英美高加索人群有一定差异.  相似文献   
106.
目的观察CT导向下125I粒子植入治疗肺转移癌的临床疗效。方法15例肺转移癌患者,男8例,女7例,15例病灶数为58个,平均每人3.9个病灶,病灶平均直径为2.5cm。在CT导向下将125I粒子植入肺转移瘤灶内,采用治疗计划系统计算布源;对残留厚度≤1.0cm的肿瘤选择平面植入方法,采用18.5~29.6MBq活度的125I粒子相隔1.0~1.5cm平面播植。结果15例58个病灶,完全缓解31个;部分缓解14个;无变化8个;进展5个。总有效率77.6%。结论放射性粒子植入治疗肺部转移癌临床疗效好,创伤小,并发症发生率低。  相似文献   
107.
The present study investigated the age-related alterations in responses of the nucleus basalis magnocellularis (nbM) neurons to frontal cortex (FCX) stimulation. Single unit extracellular recording from the nbM neurons were obtained with glass micropipettes in urethane-anesthetized rats. A total of 137 units were located within the nbM in the three age groups (young, 3 months; adult, 12 months; old, 24 months). FCX stimulation elicited responses in 91% of the 137 neurons. Most of them were excited. The frequency of occurrence of excitatory responses in the nbM neurons was decreased with aging. The thresholds and latencies of excitatory responses evoked by FCX stimulation were increased in old rats. The mean peak-firing rate of exciting phase was gradually reduced with aging. These findings indicate that there might be some functional changes in the nbM neurons with aging.  相似文献   
108.
肝毒清颗粒对大鼠实验性肝纤维化的防治作用   总被引:3,自引:0,他引:3  
目的 :观察肝毒清颗粒的抗纤维化作用。方法 :将Wistar雄性大鼠随机分成 6组 ,即正常对照组、模型组、肝毒清大、中、小剂量组和乙肝宁阳性组 ,采用四氯化碳诱导肝纤维化模型。于造模第 2个月始给予治疗药物。实验持续 3月后将大鼠处死取血作肝功检查及取肝组织做病理检查。结果 :肝毒清能降低AST ,升高TP、ALB ,与模型组比较 (P <0 .0 5 ) ;减轻肝脂肪变性、减少纤维组织增生、促进肝细胞再生。结论 :肝毒清对大鼠肝纤维化有明显防治作用  相似文献   
109.
The biologic characteristics of the two human giant-cell lung carcinoma strains with high (strain D) and low metastatic potential (strain C) were studied, including karyotype of chromosome, intracellular free calcium ([Ca2+]i), morphologic changes of cell surface and the expression of nm23-H1, p53, ras, c-myc, c-erbB2, bcl-2 genes and PCNA. The correlation between different biologic features and the metastatic potential of the two strains was analyzed. We found: 1) Both strains had the karyotypic abnormality of -13, -14, -15, +20, +21 with seven same marker chromosomes. Only strain D had the karyotypic abnormality of +7, -17, -18, +X, 7p+; 2) [Ca2+]i of the strain C (984.7 +/- 573.8) and D (517.6 +/- 216.6) was significantly different (p < 0.05). The amplitude of intracellular calcium oscillations of strain C was lower than the one of strain D; 3) strain C had more villous-like protrusions on the cell surface, whereas strain D had more bubble-like protrusions; 4) The expression of nm23-H1 and p53 protein of strain C was all higher than that of strain D. The expression of PCNA of strain C was lower than strain D; 5) nm23-H1 mRNA levels of strain C was lower than that of strain D. We consider that the karyotype of chromosomes, intracellular free calcium, the structure of cell membrane and the expression of nm23-H1 gene, p53 gene, PCNA could be closely related to the metastatic potential of human giant-cell lung carcinoma. They could be used as the sign for judging whether the tumor will metastasize in clinical practice as well as in judging the prognoses of patients.  相似文献   
110.
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