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11.
The effects of co-culture of human spermatozoa with human immortalized endometrial cells - epithelial or stromal - on sperm movement characteristics, including hyperactivation, were studied using computer- assisted sperm analysis (CASA). Epithelial and stromal cell types could be separated following 8-10 days of culture of endometrial cells originating from human biopsies. Both cell types were immortalized by the SV 40 large T antigen. Co-incubation of sperm with epithelial and stromal monolayers enhanced the rate of hyperactivation: 24.9% (P <0.05) and 17.8% (P = 0.05) versus 9.5% as control, respectively, whereas the majority of motility parameters remained unchanged. Conditioned media had no effect upon sperm parameters, including hyperactivation. Co-incubation with either monolayer was able to maintain sperm motility over a longer period than incubation in control medium alone. In four patients whose spermatozoa did not exhibit hyperactivation, co-incubation with epithelial cells, but not conditioned medium, allowed normal rates of hyperactivation (range: 6.9- 15.6%).   相似文献   
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Superoxide, an agent which attenuates the half-life of nitric oxide, is metabolized and synthesized by superoxide dismutase (SOD) and xanthine oxidase, respectively. Over the last few years much work has focused on the role of nitric oxide in human parturition. The aim of this study was to determine whether the onset of human parturition is associated with a change in the expression of copper/zinc superoxide dismutase (Cu/Zn SOD), manganese superoxide dismutase (Mn SOD) or xanthine oxidase within the uterus. Samples of myometrium, placenta, decidua and fetal membranes were obtained from women before and after the onset of labour at term. Immunocytochemistry was used to localize Cu/Zn SOD, Mn SOD and xanthine oxidase and measure SOD enzyme activity. Cu/Zn and Mn SOD-like immunoreactivity was detected in syncytiotrophoblast cells, villous stromal cells and endothelial cells of blood vessels in the placenta. In the myometrium Cu/Zn and Mn SOD were localized to myocytes and endothelial cells and to some vascular smooth muscle cells. In the fetal membranes we observed staining for Cu/Zn SOD and Mn SOD in the amnion, chorion, extravillous trophoblast and decidua. There was no difference in SOD enzyme activity or staining intensity for SOD between different cell types before and during labour. Xanthine oxidase immunoreactivity was identified in each of the tissues examined and again there was no difference in immunostaining in tissues obtained from women delivered before or after the onset of labour. These results show that the pregnant uterus is capable of both synthesizing and degrading superoxide and suggest that superoxide dismutase and xanthine oxidase may play a role in the maintenance of uterine quiescence during pregnancy, but not in the initiation of parturition.   相似文献   
14.
A multiplex PCR toxigenic culture approach was designed for simultaneous identification and toxigenic type characterization of Clostridium difficile isolates. Three pairs of primers were designed for the amplification of (i) a species-specific internal fragment of the tpi (triose phosphate isomerase) gene, (ii) an internal fragment of the tcdB (toxin B) gene, and (iii) an internal fragment of the tcdA (toxin A) gene allowing distinction between toxin A-positive, toxin B-positive (A+B+) strains and toxin A-negative, toxin B-positive (A−B+) variant strains. The reliability of the multiplex PCR was established by using a panel of 72 C. difficile strains including A+B+, A−B−, and A−B+ toxigenic types and 11 other Clostridium species type strains. The multiplex PCR assay was then included in a toxigenic culture approach for the detection, identification, and toxigenic type characterization of C. difficile in 1,343 consecutive human and animal stool samples. Overall, 111 (15.4%) of 721 human samples were positive for C. difficile; 67 (60.4%) of these samples contained A+B+ toxigenic isolates, and none of them contained A−B+ variant strains. Fifty (8%) of 622 animal samples contained C. difficile strains, which were toxigenic in 27 (54%) cases, including 1 A−B+ variant isolate. Eighty of the 721 human stool samples (37 positive and 43 negative for C. difficile culture) were comparatively tested by Premier Toxins A&B (Meridian Bioscience) and Triage C. difficile Panel (Biosite) immunoassays, the results of which were found concordant with toxigenic culture for 82.5 and 92.5% of the samples, respectively. The multiplex PCR toxigenic culture scheme described here allows combined diagnosis and toxigenic type characterization for human and animal C. difficile intestinal infections.  相似文献   
15.
Detecting pre-ovulatory luteinizing hormone surges in urine   总被引:2,自引:1,他引:2  
The study objectives were to determine (i) if pre-ovulatory luteinizing hormone (LH) surges, undetected in urine by two immunoradiometric assays (IRMA), were detectable by an ultrasensitive immunofluorometric assay (IFMA) and (ii) the influence of creatinine adjustment on the detection and timing of the urinary LH surges. Daily urine specimens were contributed by healthy 25-36 year old volunteers during 14 ovulatory menstrual cycles for an epidemiological study conducted in 1983-1985. Specimens were selected as having been previously assayed by two IRMA without consistently detecting LH surges. These urine specimens were remeasured using an IFMA and adjusted for creatinine concentration. IFMA measurements revealed unambiguous LH surges in all cycles. Adjusting IRMA urinary LH values for creatinine concentrations revealed previously undetected LH surges in four of eight cycles. Creatinine adjustment also altered the timing of IRMA and IFMA LH surges by 1-5 days. These results demonstrate an IFMA that detects pre- ovulatory LH surges in unpreserved, frozen urine from cycles where such surges were previously undetectable. Further, creatinine adjustment can markedly affect detection and timing of the onset and peak of the urinary LH surge. While our analysis suggests that this adjustment improves the validity of the LH measure, this requires further investigation.   相似文献   
16.
The aim of this study was to compare the efficacy of pure follicle stimulating hormone (FSH) with that of FSH/human menopausal gonadotrophin (HMG) combination in downregulated cycles. A total of 357 patients was evaluated retrospectively. Sixty percent of patients in the FSH group and 55% in the FSH/HMG group were new; the others were repeat patients. Ovulation was suppressed with leuprolide acetate in all patients, followed by either FSH (n = 218) or FSH/HMG (n = 119). There was no difference in patients' age, infertility factors, number of ampoules used, length of stimulation, oestradiol levels on day of human chorionic gonadotrophin (HCG) administration, number of oocytes recovered or the number of embryos transferred. Also, nuclear maturity at aspiration and fertilization rates were not different between the two groups. FSH stimulation resulted in a significantly higher percentage of mature oocytes that showed the typical 'mature' morphological characteristics (P < 0.0001). The clinical pregnancy rates per transfer were 40 and 28% in patients stimulated with pure FSH and FSH/HMG respectively (P < 0.05). The significantly higher number of immature oocytes matured in vitro in the FSH/HMG group (P = 0.001) suggests a possible effect on in-vitro maturation, due to luteinizing hormone present in HMG. The difference in mature oocyte quality may be an important determinant in the higher pregnancy rates for the FSH- stimulated patients.   相似文献   
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傅菊芳  戴月娥  李蕊 《医学争鸣》2000,21(10):1199-1199
1 临床资料 患者 ,女 ,6 1岁 ,1999- 0 6 - 0 3日确诊为急性红白血病 (M6 ) .先后 4次住院 ,鉴定血型均为 O型 . 2 0 0 0 - 0 1- 2 2日复诊 ,正反鉴定表明 ,患者红细胞与抗 - B不凝集 ,与抗 - A凝集 ,血清中有抗 - B抗体 (表 1) ,吸收释放试验证实为 A型 (表2 ) .输 A型浓缩红细胞 2 μ,无不良反应 .表 1 血型正反鉴定试剂血清试剂红细胞标本抗 A 抗 B 抗 A+ B Ac Bc Oc被检红细胞 2 + -3+ ---自身血清 -3+ -表 2 吸收、放散试验被检 RBC吸收抗血清后上清被检 RBC吸收抗血清后释放液试剂细胞抗 A修正液抗 B修正液抗 A修正液抗…  相似文献   
19.
综合疗法治愈狼疮性急性肾衰1例   总被引:3,自引:2,他引:1  
杨洁  孙脊峰 《医学争鸣》2000,21(4):398-398
1 病例报告 患者 ,女 ,6 0岁 ,因反复发热 2 5 a、全身性关节疼痛 2 3 a,双下肢水肿 2 mo,腹胀、尿少 1mo,于 1998- 10 - 2 0入院 .1975年患者出现发热 ,全身关节疼痛 ,四肢关节周围皮肤出现结节性红斑 ,触之疼痛 ,多次化验血沉 115 mm· h- 1 ,抗核抗体阴性 ,类风湿因子阳性 ,未找到狼疮细胞 ,诊断为“类风湿性关节炎”.1986年因上述症状复发再次入我院 ,多次检查后发现血抗核抗体 ( ) ,抗双链 DNA抗体 ( ) ,临床确诊为系统性红斑狼疮 (SL E) ,狼疮性肝炎 ,狼疮性胸膜炎 ,狼疮性肺炎 .经治疗好转 ,但上述症状反复发作 .此次上述症状复…  相似文献   
20.
During a 2-week period, three infants with a cough lasting at least 8 days with whoops, were admitted to the pediatric unit; Bordetella pertussis was isolated from nasopharyngeal aspirates collected from the three infants. Approximately 1 week later, a nurse working on the same unit developed influenza-like symptoms followed by whooping cough; B pertussis was isolated. Isolates from the nurse and from one of the infants were shown to be indistinguishable by pulsed-field gel electrophoresis. These data demonstrate that B pertussis transmission to healthcare workers is possible and emphasize the need to use respiratory protection devices (Droplet Precautions) for healthcare workers having close contact with infected children.  相似文献   
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