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101.
102.
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   
103.
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   
104.
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   
105.
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   
106.
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   
107.
We describe an ELISA for trophozoite-specific IgA in the intestinal secretions of mice infected with Giardia muris. Using this method, trophozoite-specific IgA was demonstrated in intestinal secretions of Giardia-infected immunocompetent BALB/c mice. Such antibody was undetectable in the intestinal secretions of Giardia-infected athymic (nude) mice. Immunocompetent BALB/c mice are able to clear G. muris infection whereas nude mice are not. The study provides evidence that the chronicity of G. muris infection in nude mice results from lack of intestinal trophozoite-specific IgA in these animals. By means of the ELISA, trophozoite-specific IgA was demonstrated in intestinal secretions from immunocompetent mice in the absence of protease inhibitors.  相似文献   
108.
目的 为了解氯喹敏感和抗性株恶性疟原虫对青蒿琥酯、克林霉素及其二联用的敏感性。方法 运用Rieckmann体外微量法测定原虫对药物的敏感性。结果 氯喹敏感株恶性疟原虫对青蒿琥酯、克林霉素及青/克联用的ID50分别为2.8、3784.7及6.4/2046.6nmol/L;抗性株原虫对上述药物的ID50分别为8.1、1652.1及2.35/1409.4nmol/L。结论 抗氯喹恶性疟原虫对克林霉素无交叉抗性。青蒿琥酯与克林霉素联用在体外测定中,其抗疟作用对抗性株明显优于敏感株。  相似文献   
109.
用ELISA检测肺癌患者血清中Endostatin的变化   总被引:2,自引:0,他引:2  
目的建立快速敏感的ELISA方法检测肺癌患者血清内皮抑素(Endostatin)。方法对41例肺癌患者及22例良性肺病患者进行血清Endostatin测定并与20例正常人进行比较。结果肺癌患者体内Endostatin水平高于良性肺病患者和正常人。结论快捷的ELISA检测法可以成为人们在临床及基础研究Endostatin的新方法。  相似文献   
110.
吲哚美辛对人结肠癌HCT116和SW480细胞的影响   总被引:3,自引:0,他引:3  
目的:探讨吲哚美辛对人结肠癌HCT116和SW480细胞的影响。方法:体外培养细胞,采用MTT法分别检测吲哚美辛作用后两系细胞的生长情况,计算半抑浓度(IC50);体内建立裸鼠皮下移植瘤模型,喂服吲哚美辛3 mg/(kg·d)共4周,隔日测瘤结节体积及鼠重,评价吲哚美辛的抑瘤效果。结果:吲哚美辛作用于结肠癌HCT116和SW480细胞48 h后,细胞的生长均受到明显抑制,呈剂量依赖效应,IC50分别为 (318.2±12.7) μmol/L和 (701.4±29.5) μmol/L;吲哚美辛显著减慢裸鼠皮下移植瘤的生长,用药4周后抑瘤率达44.6%,未见明显毒性反应。结论:吲哚美辛能抑制不表达环氧合酶的人结肠癌细胞(HCT116和SW480)生长,间接说明其抗癌作用不完全依赖环氧合酶途径,还存在其它的可能机制。  相似文献   
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