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The purpose of this study was to investigate any influence of maternal and/or paternal age on gamete characteristics and pregnancy outcomes in intracytoplasmic sperm injection (ICSI) cycles. In all, 821 consecutive ICSI cases were analysed retrospectively. While a significant linear decline in semen volume was detected, no significant differences in the concentration, motility or morphology of the spermatozoa were found with paternal ageing. A significant decline in the number of oocytes retrieved and the number of mature oocytes obtained was found with advancing maternal age. An increase in the occurrence of digyny was noted with parental ageing, while no difference in single or bipronuclear fertilization was found. Older women had a decreased incidence of single pronucleus formation and an increase in digyny, but no significant difference in the percentage of oocytes that underwent two-pronuclear fertilization was detected with regard to maternal ageing. Pregnancy outcomes were not influenced by the age of the male partner, while a strong negative correlation was found with maternal ageing. To better analyse male partner ageing as a factor affecting pregnancy outcome, we analysed a subgroup of patients with a female partner aged <35 years who underwent ICSI. No paternal influence on ICSI pregnancy outcome was found in this subgroup of patients. We conclude that the influence on pregnancy outcome after ICSI is related mostly to maternal and not paternal age.   相似文献   
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1-溴-2-甲氧基萘与0-对在苯磺酰乳酸乙酯(1)在无水氯化铝催化下化Friedel-Crafts反应,还原脱溴直接合成dl-1a萘普生(3),以上反应均在“一锅”内完成,收率达95。  相似文献   
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适当使用时,LABAs利大于弊,可继续用于治疗哮喘。FDA建议仅用于哮喘控制药物如吸入性皮质激素不能有效缓解病情的患者。  相似文献   
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Iron overload disorders have been the focus of several quantification studies involving non-invasive imaging modalities. Neutron spectroscopic techniques have demonstrated great potential in detecting iron concentrations within biological tissue. We are developing a neutron spectroscopic technique called neutron stimulated emission computed tomography (NSECT), which has the potential to diagnose iron overload in the liver at clinically acceptable patient dose levels through a non-invasive scan. The technique uses inelastic scatter interactions between atomic nuclei in the sample and incoming fast neutrons to non-invasively determine the concentration of elements in the sample. This paper discusses a non-tomographic application of NSECT investigating the feasibility of detecting elevated iron concentrations in the liver. A model of iron overload in the human body was created using bovine liver tissue housed inside a human torso phantom and was scanned with a 5 MeV pulsed beam using single-position spectroscopy. Spectra were reconstructed and analyzed with algorithms designed specifically for NSECT. Results from spectroscopic quantification indicate that NSECT can currently detect liver iron concentrations of 6 mg g(-1) or higher and has the potential to detect lower concentrations by optimizing the acquisition geometry to scan a larger volume of tissue. The experiment described in this paper has two important outcomes: (i) it demonstrates that NSECT has the potential to detect clinically relevant concentrations of iron in the human body through a non-invasive scan and (ii) it provides a comparative standard to guide the design of iron overload phantoms for future NSECT liver iron quantification studies.  相似文献   
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