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排序方式: 共有406条查询结果,搜索用时 31 毫秒
61.
J Domitrz S Wo?czyński M Syrewicz J Szamatowicz W Kuczyński D Grochowski M Józwik M Szamatowicz 《Ginekologia polska》1999,70(1):13-19
OBJECTIVES: It has been suggested that monozygotic pregnancies occur more frequently after in vitro fertilisation. This phenomenon is attributed to a number of factors including in vitro culture conditions, malformation of the zona pellucida due to manipulation on the oocytes and artificial opening of the zona pellucida. DESIGN: Retrospective analysis of monozygotic pregnancies in an IVF-ET procedures and obstetrical these pregnancies outcome. MATERIALS AND METHODS: A total of 2254 IVF-ET procedures were analysed. Three protocols were used for ovarian stimulation: short or long protocols with gonadotropins releasing hormone analogue or clomiphene citrate with hMG. In 811 cases male factor was diagnosed and intracitoplasmatic sperm injections were performed. RESULTS: 549 clinical pregnancies were achieved in analysed group. In six cases ultrasound examination 5 weeks after embryo transfer showed a greater number of foetus than the number of embryo transferred. In three of those cases the embryos were obtained after ICSI. Age and average thickness of zona pellucida were similar in group of patients with monozygotic pregnancies when compared with all pregnant patients after IVF treatment. CONCLUSIONS: The incidence of monozygotic pregnancy is increased in group pregnancies resulting from IVF ET. No single risk factor can explain this phenomena. This type of pregnancy needs special obstetrical attention. 相似文献
62.
The outcome of intracytoplasmic injection of fresh and cryopreserved ejaculated spermatozoa--a prospective randomized study 总被引:1,自引:0,他引:1
Kuczyński W Dhont M Grygoruk C Grochowski D Wołczyński S Szamatowicz M 《Human reproduction (Oxford, England)》2001,16(10):2109-2113
BACKGROUND: The overall aim of this prospective, randomized study was to compare the reproductive potential of fresh and frozen-thawed ejaculated spermatozoa from oligoasthenoteratozoospermic patients in an intracytoplasmic sperm injection (ICSI) procedure. METHODS: All patients consenting to participate in this study had a sperm sample frozen prior to the start of a cycle. Patients were randomized using a random number table to undergo ICSI with either fresh (group A, n = 118) or frozen-thawed (group B, n = 122) spermatozoa. All prognostic variables were equally distributed among the two groups. RESULTS: The pregnancy rate per started cycle was 29.7% in group A and 38.5% in group B, P > 0.05. A significant difference was observed in the rate of ongoing pregnancies between group A (23.7%) and group B (35.2%), P < 0.05. CONCLUSION: From our data we can conclude that cryopreservation of spermatozoa from men with poor sperm quality does not negatively affect fertilization and pregnancy rates after ICSI. A larger study will be needed to investigate whether the use of cryopreserved spermatozoa can be helpful in selecting the most vital spermatozoa for ICSI. 相似文献
63.
Management of small‐bowel fistulas which are in an open abdomen and have no soft tissue overlay or a fistula tract involves many complications and challenges. Controlling the local leakage of enteric contents has a central role in the success of medical treatment. There are several methods to deal with fistula discharge but unfortunately, the technical solutions only partially address such problems and a definitive management of fistula discharge still remains an insoluble challenge. We describe a simple and cheap method to control fistula leakage by using a percutaneous endoscopic gastrostomy tube. 相似文献
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OBJECTIVE: To prospectively document the prevalence of otitis media with effusion (OME) in 86 African-American children between ages 2 and 5 years. STUDY DESIGN: Eighty-six children in center-based child care whose ear status had been followed from infancy continued to be observed. Middle ear status was assessed by pneumatic otoscopy and tympanometry biweekly. RESULTS: The prevalence of OME decreased as children became older. The mean proportion of examinations demonstrating bilateral OME (BOME) ranged from 12% between 24 to 30 months to 4% between 54 to 60 months of age. The mean proportion of exams revealing bilateral normal ears increased from 77% at 24 to 30 months to 88% at 54 to 60 months of age. Although 60 children had experienced BOME that lasted 4 months or longer in the 6- to 24-month age period, only 8 of these children experienced at least 4 months of continuous BOME between 24 to 60 months. CONCLUSIONS: The proportion of time with BOME decreased progressively with increasing age in this population. Only 8 of 60 children who had experienced more than 4 consecutive months of BOME before 2 years of age continued to manifest persistent effusion or experience recurrences of prolonged BOME after 2 years of age. 相似文献
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血小板冷藏会使血管假性血友病因子受体复合物(von Willebrand factor receptor complex)聚集成簇。巨噬细胞αMβ2 整合素结合在成簇复合物的GPIbα亚基,导致输注的冷藏血小板被快速清除。因此输注用血小板不能冷藏,但现在的室温保存方式也存在很大缺点。我们已证明αMβ2是一种凝集素,它能识别GPIbα的N-连接葡聚糖上暴露的β-N-乙酰葡萄胺。冷藏血小板的酶促半乳糖苷化阻止了αMβ2的这种识别,延长了有 相似文献
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