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11.
Glutathione (GSH), GSH peroxidase (GPX), GSH reductase (GRD), superoxide dismutase (SOD) and catalase-like enzyme activity were quantified in seminal plasma from normozoospermic patients, men with known distal ductal occlusion, proven fathers and male partners of couples receiving in-vitro fertilization (IVF) treatment for both male and female causes. Glutathione was non-detectable (< 2.5 microM) in seminal plasma. None of the enzyme activities per unit volume were lower in semen from vasectomized men, suggesting that they did not originate substantially from the testis or epididymis. The strongest relationships between enzyme activities and accessory gland markers were between zinc and GRD (r = 0.678), SOD (r = 0.602) and GPX (r = 0.548), suggesting a largely prostatic origin of these enzymes. Only weak relationships between accessory gland markers and catalase-like activity suggested a multi-glandular source of this enzyme. There was no relationship between the activity of any of the enzymes in the IVF patients with their fertilization rates in vitro or the establishment of pregnancy after IVF. Nor was there any correlation of enzyme activity with the morphology and percentage of motile spermatozoa in semen or with the percentage motility of spermatozoa immediately after swim-up or after overnight incubation. These findings suggest that the protective enzymes in the seminal plasma are contributed largely by the prostate and little by the epididymis, and that in most cases of IVF, they have no major influence on the outcome.   相似文献   
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We have recently reported isolation of the gene responsible for X- linked Opitz G/BBB syndrome, a defect of midline development. MID1 is located on the distal short arm of the human X chromosome (Xp22. 3) and encodes a novel member of the B box family of zinc finger proteins. We have now cloned the murine homolog of MID1 and performed preliminary expression studies during development. Mid1 expression in undifferentiated cells in the central nervous, gastrointestinal and urogenital systems suggests that abnormal cell proliferation may underlie the defect in midline development characteristic of Opitz syndrome. We have also found that Mid1 is located within the mouse pseudoautosomal region (PAR) in Mus musculus , while it seems to be X- specific in Mus spretus. Therefore, Mid1 is likely to be a recent acquisition of the M. musculus PAR. Genetic and FISH analyses also demonstrated a high frequency of unequal crossovers in the murine PAR, creating spontaneous deletion/duplication events involving Mid1. These data provide evidence for the first time that genetic instability of the PAR may affect functionally important genes. In addition, we show that MID1 is the first example of a gene subject to X-inactivation in man while escaping it in mouse. These data contribute to a better understanding of the molecular content and evolution of the rodent PAR.   相似文献   
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The localisation of the principal blood group antigens has been studied in human liver. These blood group antigens included the erythrocyte antigens and the antigen of the major histocompatibility complex. This study was performed by the indirect immunofluorescence technique using polyclonal antibodies of human or animal origin and monoclonal antibodies from hybridomas. This study has shown that the normal hepatocyte is lacking in blood group antigens. On the contrary, the biliary cell was rich in antigenic markers: the main antigens expressed were Lewis, Pr, HLA-A and B antigens. In Kupffer cells, only i and HLA-DR antigens were clearly expressed. The endothelial cells of blood vessels mainly show A, B, H, HLA-A and B antigens; HLA-DR and Pr are slightly expressed. HLA-DR antigens were more strongly expressed on veins than on arteries. Dendritic cells have been identified in the portal space of human liver. They bore i and HLA-DR antigens.  相似文献   
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In this study we evaluated efficacy and toxicity of a neoadjuvant chemotherapy regimen before radiation therapy or surgery in high-risk cevical cancer patients. Between January 1988 and July 1993, 37 out of 40 consecutive patients with bulky cervical carcinoma (>40 mm) received chemotherapy consisting of six (range 4-9) weekly courses of cisplatin (1 mg/kg), followed by radical surgery and/or radiotherapy. Thirty-six patients completed the planned sequence of treatment. Overall response rate was 65% after induction chemotherapy (complete 0% and partial 65%) and 73% (complete 57% and partial 16%) after definitive treatment. After a median follow-up of 23 (range 4-61) months the median duration of response was 29, 19 and 11 months for complete partial and non-responders respectively. Toxicities from induction chemotherapy were mild to moderate, reversible and tolerable and did not affect the subsequent application of the definitive treatment. The proposed cisplatin neoadjuvant chemotherapy regimen gave positive results in a good number of cases with low toxicity and without interfering with the definitive radio-surgical treatment of this group of high-risk patients. The number of cisplatin courses for best effect remains to be established.  相似文献   
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异一枝蒿酮酸的结构   总被引:3,自引:0,他引:3  
从新疆一枝蒿(Artemisia rupestris L.)中分得一个新成分,命名为异一枝蒿酮酸(isorupestonic acid),根据光谱(IR,UV,MS.NMR),X-ray晶体衍射及CD谱分析,确定其结构及绝对构型。并经X-ray晶体衍射及CD谱分析修正了一枝蒿酮酸的绝对构型。  相似文献   
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