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71.
卡介苗对哮喘豚鼠的影响   总被引:3,自引:2,他引:1  
目的 研究卡介苗对哮喘豚鼠的防治作用。方法 24只豚鼠随机分为阳性对照组、地塞米松组、卡介苗组及阴性对照组,每组6只,除阴性对照组用生理盐水外,其余三组每只腹腔内注射鸡卵蛋白100mg,2周后用1%鸡卵蛋白激发致敏,每次30min,每日1次,持续3d,地塞米松组每次激发前肌注地塞米松2mg/kg,卡介苗组每次激发前肌往卡介苗30mg/kg,阳性对照组每次激发前30min肌注生理盐水2ml,最后用乌拉坦麻醉,检验动脉血气分析参数,嗜酸粒细胞(EOS)计数等参数,所有参数用t检验或卡方检验分析。结果 阳性对照组与其它三组比较,在豚鼠的发病程度、动脉血气分析、外周血EOS计数、支气管肺泡灌洗液中EOS计数、支气管病理切片每20个高倍视野EOS计数均有明显差异(P<0.05或P<0.01)。结论 卡介苗能够抑制动物模型中的哮喘反应。  相似文献   
72.
白花前胡甲素对心肌缺血再灌注大鼠血清IL-6水平的影响   总被引:1,自引:0,他引:1  
目的 探讨白花前胡甲素 (Pd Ia)抗缺血再灌注损伤的机制 ,为寻找高效、低毒及安全的防治缺血再灌注损伤的药物提供理论基础。方法 采用放射免疫分析测定血清IL— 6水平 ,并通过常规HE染色比较中性粒细胞等炎性细胞的心肌浸润情况。结果 Pd Ia低、中、高三个剂量组IL— 6水平分别由对照组的 (15 2 88±15 2 5 ) pg/ml降至 (12 8 45± 18 37)pg/ml、 (119 6 6± 15 72 ) pg/ml和 (116 13± 10 45 )pg/ml (P <0 0 1) ,其作用强度与硝苯地平相近 (12 3 5 5± 18 6 2 )pg/ml。 结论 Pd Ia明显抑制缺血再灌注大鼠血清IL— 6水平 ,提示Pd Ia可能通过抑制NF—kB途径实现再灌注性损伤的防治  相似文献   
73.
The cytotoxicity of extracts from rice cultures of five Fusarium avenaceum strains against the porcine epithelial kidney cell-line PK-15 was investigated using the Alamar Blue™ assay. After the identification of known fungal metabolites, cytotoxic extracts were fractionated using semi-preparative reversed-phase HPLC and normal phase LC, and the fractions were tested for cytotoxicity. In this way, two different groups of metabolites were identified as the major cytotoxic principles of the extracts. High concentrations of enniatins, especially enniatins B and B1, inhibited the metabolic activity of PK-15 cells. Furthermore, an unidentified metabolite, produced in high amounts by a strain that produced relatively small amounts of enniatins, was also found to be cytotoxic to PK-15 cells. This study shows that enniatins, a group of cyclic depsipeptides, which have been ignored as significant contributors to the toxicity of fungal extracts, may account for most of the observed effect for F. avenaceum.  相似文献   
74.
The analogues [Glu(OBzl)11]SP6–11 and [Glu(OBzl)11]SP5–11 of the C-terminal hexapeptide and heptapeptide of Substance P have been synthesized by conventional solution methods. In each analogue the SCH3 group of Met11 is replaced by the COOCH2C6H5 group. The in vitro activity of both analogues has been determined on three biological preparations: guinea pig ileum (GPI), rat vas deferens (RVD), and rat portal vein (RPV). The selectivity for the different receptors has been studied by utilizing atropine-treated guinea pig ileum (GPI + At). The results showed that both analogues are mainly active on GPI through the NK-1 receptor and that both analogues are equipotent to Substance P.  相似文献   
75.
76.
Summary. The study was conducted to evaluate the diverse effect and clinical significance of TEST yolk buffer treatment on sperm samples of 128 infertile men. Sperm samples were incubated with TEST yolk buffer and control medium (Ham's F-10) at room temperature for 2 h. The hemizona indices (mean ± SE) of the TEST yolk buffer and medium-treated sperm samples were 29 ± 2.3% and 22 ± 1.6%, respectively. Inspection of the individual response of each sperm sample to TEST yolk buffer revealed that 63 samples (49%) improved (double the interassay variation = 28%) their binding to zona pellucida, 36 (28%) remained unchanged, whereas the binding capacity of 29 samples (23%) decreased. Furthermore, TEST yolk buffer treatment of 24 samples (19%) resulted in an increased binding beyond the hemizona index threshold set up at 23%. This level was previously shown to be the cut-off point between fertile and infertile sperm samples. It was concluded that when applied to an unselected group of infertile men, TEST yolk buffer significantly increased sperm binding capacity to the zona pellucida. However, only 19% of the sperm samples showed improvement with clinical significance. The other sperm samples may have improved, remained unchanged or even deteriorated independently on basic sperm variables. Thus, the effect of TEST yolk buffer treatment on sperm binding should be tested prior to its clinical use to avoid possible damage to certain sperm samples.  相似文献   
77.
黄芪多糖对LAK细胞毒的增强作用   总被引:7,自引:0,他引:7  
王光  娄丹 《中国公共卫生学报》1992,11(4):233-234,244
本文采用乳酸脱氢酶(LDH释放法研究了黄芪多糖(APS)对淋巴因子活化的杀伤细胞(LAK)的增强作用。结果表明:APS具有明显的增强LAK细胞毒作用,有效剂量范围为0.001mg/ml~0.01mg/ml,在0.01mg/ml呈最大的增强作用,为原LAK细胞毒性的3倍。同时也证实黄芪水煎剂本身也具有一定的增强作用。  相似文献   
78.
Genotyping of platelet alloantigens with the possibility of using any type of cellular material as a source of DNA has become a preferred procedure, particularly in thrombocytopenic patients when platelet counts are too low for phenotyping. Recently human platelet antigen 1 (HPA-1) has been identified as an inherited risk factor for coronary thrombosis. The different detection methods currently used have disadvantages for large-scale DNA diagnosis, including the need for electrophoresis (allele-specific restriction enzyme analysis, amplification with sequence-specific primers) or the potential risk of reduced specificity (allele-specific oligonucleotide hybridization). In this report we describe the adaptation of an automated oligonucleotide ligation assay to genotype HPA-1 in polymerase chain reaction (PCR)-amplified DNA samples. HPA-1a and HPA-1b phenotypes corresponded to the results of the different genotyping assays. The genotypes determined with the ELISA-based PCR-oligonucleotide ligation assay were in 100% concordance with the results obtained by conventional allele-specific restriction enzyme site analysis and PCR amplification with sequence-specific primers. The automated oligonucleotide ligation assay provides a rapid, reliable, nonisotopic method to genotype human platelet antigens that can rapidly be applied to large population screening.  相似文献   
79.
为探讨用ELISA法(酶联免疫吸附试验)检测血清抗PPD(结核菌素纯蛋白衍生物)IgG抗体对儿童结核的诊断意义,对42例儿童结核、30例儿童肺炎及16例健康对照者进行了检测,阳性率分别为92.85%、6.66%、6.25%。结核病例经六个月正规化疗后,阳性率明显降低,说明此项检测可做为一项诊断儿童结核及评价疗效的指标。  相似文献   
80.
Swabbing the urethrae of men has been the traditional approach for collecting specimens for detection of Chlamydia trachomatis . Recently, however, urine testing using enzyme immunoassay has yielded promising results. A total of 105 patients attending the Andrology Clinic at Ga Rankuwa Hospital, Medunsa were included in the study. These patients were asymptomatic and had no urethral discharge. Three endo-urethral swabs and first-catch urine were collected fiom each patient. The urethral swabs were used for enzyme immunoassay (EIA) (IDEIA 111), tissue culture and direct immonufluorescent antibody (DFA) test (IMAGEN) to detect C. trachomatis . In addition about 15–30 ml of first-catch urine, or urine collected at least 2h after the previous micturition, was collected for each patient for EIA testing. Fifteen (14.3%) of 105 patients were positive on urethral swab EIA, in comparison with the DFA test in which 14 (13.3%) were positive. Eight (7.8%) were positive in tissue culture. Urine EIA was positive in 17 (16.2%) patients, of whom five (4.8%) were positive in urine EIA only. All EIA positive urines were confirmed by DFA. We recommend that first-catch urine or urine collected at least 2h after the previous micturition in infertile males may be considered a suitable alternative to urethral swab for chlamydial diagnosis because it is noninvasive and nontraumatic.  相似文献   
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