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21.
Previous studies have suggested that human follicular fluid contains factors that reduce the zona-binding capacity of spermatozoa. The present study provides further evidence of the existence of such factors. Using the hemizona binding assay (HZA), we have shown that the inhibitory effect of human follicular fluid on the zona-binding capacity of spermatozoa is concentration-dependent, an inhibitory effect being detected when the concentration of human follicular fluid was > or = 10%. A 1% concentration of human follicular fluid did not possess this inhibitory activity. Heating human follicular fluid at 56 degrees C for 30 min did not affect its inhibitory properties; treatment with proteinase-K abolished such inhibition. Human follicular fluid was fractionated sequentially by concanavalin-A affinity chromatography, Mono Q ion-exchange chromatography and Superose-12 gel filtration. The zona binding inhibitory activity resided in the fraction which bound to the lectin and Mono Q column and contained molecules with native molecular weights of 32 and 192 kDa. Sodium dodecyl sulphate-polyacrylamide gel electrophoresis analysis suggested that the 192 kDa glycoprotein was a tetramer, while the 32 kDa glycoprotein remained as a single molecular species under denaturing conditions. We conclude that two glycoproteins were responsible for the zona binding inhibitory activity of human follicular fluid. The physiological role of these factors remains unclear.   相似文献   
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Fifty women with polycystic ovaries took part in a prospective randomized study. All women required treatment by in-vitro fertilization (IVF) for reasons other than anovulation. They had all previously undergone ovarian stimulation with gonadotrophin therapy which had failed to result in pregnancy or had been abandoned due to high risk of developing ovarian hyperstimulation syndrome (OHSS). Twenty-five women were treated by long-term pituitary desensitization followed by gonadotrophin therapy, oocyte retrieval and embryo transfer (group 1). Twenty-five women underwent laparoscopic ovarian electrocautery after pituitary desensitization followed by gonadotrophin therapy, oocyte retrieval and embryo transfer (group 2). A significantly higher number of women in group 1 had to have the treatment cycle abandoned due to impending or actual OHSS, determined by endocrine and clinical findings. In addition, the development of moderate or severe OHSS in completed cycles was higher in group 1. The pregnancy rate and miscarriage rates in the two treatment groups were similar. The authors propose that laparoscopic ovarian electrocautery is a potentially useful treatment for women who have previously had an IVF treatment cycle cancelled due to risk of OHSS or who have suffered OHSS in a previous treatment cycle.   相似文献   
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重度肥胖患者胃肠分流术后低氧血症机制的分析   总被引:2,自引:0,他引:2  
目的 研究重度肥胖对胃肠分流术后动脉血氧分压的影响。方法 对 6 1例进行胃肠分流术的重度肥胖患者及 5 5例择期腹部手术的正常体重患者进行术前肺功能、术前及术后 1~ 5d的血气分析检测。结果 肥胖组术后1~ 5d、对照组术后 1~ 2d的动脉血氧分压较术前显著下降 (P <0 .0 5 ) ;肥胖组术后 1~ 2d动脉血氧分压与其最大分钟通气量及腰臀比显著相关 (P <0 .0 0 0 1)。结论 重度肥胖者较正常体重患者在腹部手术后发生低氧血症的程度较严重且持续时间长。  相似文献   
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Formal retrospective case review and sudden infant death   总被引:2,自引:0,他引:2  
A review of 24 consecutive sudden infant deaths was undertaken to evaluate the importance of the various stages in the postmortem assessment of such cases. Death in three cases was caused by obvious trauma. Of the remainder, 16 were attributed to sudden infant death syndrome (SIDS), 4 to accidental asphyxia (identified by death scene examination and/or formal case review) and 1 to a lingual thyroglossal duct cyst. Three (14%) of 21 deaths thought to be SIDS after postmortem examination were attributed to asphyxia following subsequent formal case review.  相似文献   
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Chronic illness in adolescents: Transfer or transition to adult services?   总被引:2,自引:0,他引:2  
It is widely believed that the improved survival of young people with chronic diseases will be associated with the development of appropriate services within the adult healthcare domain. There is, however, little evidence to suggest that this is happening at a rate commensurate with clinical requirements. This paper highlights the multiplicity of barriers that impede the development of transition services to facilitate the transfer of medical care from the paediatric to the adult domain. Different models of transition care are described, and the terms 'transfer' and 'transition' are differentiated. The clinical demand for service development is highlighted, as well as the need for specific research in this area of healthcare delivery.  相似文献   
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