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991.
992.
Impact of elective single embryo transfer on the twin pregnancy rate   总被引:9,自引:0,他引:9  
BACKGROUND: It is unclear how the implementation of elective single embryo transfer in clinical practice would affect clinical pregnancy and delivery rates and multiple birth rates. METHODS: This retrospective study analysed 1871 IVF/ICSI cycles carried out from 1997 to 2001 in the IVF programme of a single university infertility clinic. RESULTS: The number of elective single embryo transfers increased from 11 to 56%. At the same time the clinical pregnancy rate was relatively stable; mean 34.0% (range 28-42). The number of embryos per embryo transfer decreased from 1.8 to 1.3. The multiple pregnancy and delivery rates dropped markedly from 25 to 7.5% and from 25 to 5% respectively. CONCLUSIONS: An elective single embryo transfer programme can be adopted in daily practice that decreases the twinning rate to <10% and does not affect the overall pregnancy rate.  相似文献   
993.
BACKGROUND: Specific subgroups of people planning IVF might be at risk of having more psychological or health-related problems. Identification of subgroups at risk may better enable allocation of appropriate counselling. METHODS: A group of 425 men and 447 women planning to undergo IVF treatment filled out a questionnaire. Four domains of health-related quality of life were measured, namely perceived emotional, physical, cognitive and social functioning. RESULTS: Young men and women (aged 21-30 years) planning IVF had more short-term social and emotional problems than people of the same age group in the general population. No substantial differences were found in cognitive and physical functioning for all age groups of men nor women planning IVF compared with the general population. A high level of irrational parenthood cognitions substantially accounted for a less optimal score on all the different domains of quality of life. These cognitions ('needing a child in order to live a happy life') were especially prevalent among younger women. CONCLUSIONS: Patients with high levels of irrational parenthood cognitions are at risk of a less optimal quality of life. A short cognitive counselling therapy is advised for patients with high levels of these cognitions.  相似文献   
994.
目的探讨不孕不育及自发流产与染色体核型异常的关系,指导临床对这些疾病的诊断。方法采集922例生殖异常患者外周静脉血,进行淋巴细胞培养,常规方法收获细胞,低渗、固定、制片、经G显带处理、镜检,进行观察研究。结果922例患者共检出异常核型66例,总检出率7.16%。其中,易位21例,倒位21例,克氏综合征18例,X-三体综合征2例,Turner综合征伴X染色体缺失1例,Y染色体缺失1例,环状21号染色体1例,额外标记染色体1例,及常见染色体多态性大Y染色体63例,发生率13.35%。结论染色体异常是导致不孕不育及自发流产的重要原因之一,对生殖异常患者进行染色体检查可为临床诊断和优生优育提供依据。  相似文献   
995.
Sildenafil is a specific inhibitor of phosphodiesterase (PDE) type 5 and represents a powerful therapy for male erectile dysfunction (ED) of different aetiology. Recently, sildenafil has been shown to restore erections in temporary ED related to the need of semen collection for assisted reproductive techniques. In this study, we investigated whether sildenafil administration modifies seminal parameters and/or erectile function in normal healthy volunteers. In a double-blind, randomized, placebo-controlled, cross-over two period investigation we enrolled 20 healthy male volunteers (mean +/- SE age 32 +/- 0.5 years). Subjects were not using any medication for the 3 month period prior to the study and were engaged in a stable relationship with proven fertility. The effects of sildenafil (100 mg) on seminal parameters and erectile function after audiovisual sexual stimulation were evaluated by semen analysis and by colour-Duplex ultrasound (the Resistive Index) respectively. In all subjects, sildenafil caused no changes in seminal and erection parameters when compared to placebo. Interestingly, sildenafil administration led to a marked reduction of the post-ejaculatory refractory time (10.8 +/- 0.9 min versus 2.6 +/- 0.7 min for placebo and sildenafil respectively; P < 0.0001). These results indicate that in normal subjects acute sildenafil treatment does not modify semen characteristics and has a positive influence over the resumption of erections following ejaculation in the presence of a continuous erotic stimulus.  相似文献   
996.
A scoring system specific for day 3 embryos has not been extensively explored. Most IVF laboratories continue to grade embryos solely on the basis of cell number and percentage fragmentation as was traditionally done for day 2 embryos. Additional morphological features, some unique to day 3 embryos, may be useful in selecting embryos most likely to blastulate and implant. The objective of this study was to derive an embryo scoring system for day 3 transfers which is predictive of positive pregnancy outcomes. A total of 316 transferred embryos from 93 patients was recorded on videotape and evaluated. The following parameters were used to grade the embryos: cell number, fragmentation pattern (FP), cytoplasmic pitting, compaction, equal sized blastomeres, blastomere expansion and absence of vacuoles. The clinical pregnancy rate was 41.9%, with an implantation rate of 18% per embryo transferred. The mean number of embryos transferred per patient was 3.4. Three formulae were derived to score embryo quality in each transfer based on the average score of individual embryos transferred. In the first scoring system, cell number alone was used to predict pregnancy outcome. The second scoring system was based on blastomere number and the observed FP. The third scoring system utilized both blastomere number and FP but also combined this with five morphological criteria to yield a final day 3 embryo quality (D3EQ) score. We found the D3EQ score to be prognostic of pregnancy outcome. This study suggests that although cell number and FP are certainly predictors of positive pregnancy outcomes, additional parameters specific to day 3 embryos should be used to stratify a cohort of embryos further.  相似文献   
997.
BACKGROUND: Data on the effect of elective single embryo transfer (eSET) on the total and multiple pregnancy rates of an IVF/ICSI programme are reported. METHODS AND RESULTS: A retrospective cohort analysis of eSET was carried out over a 4 year period. A total of 1559 cycles resulted in 1464 transfers; 299 transfers of one top quality embryo (20.4%) and 86 of one non-top quality embryo (5.9%) yielded 149 conceptions (49.8%) with 105 ongoing pregnancies (35.1%) and 26 conceptions (30.2%) with 19 ongoing implantations (22.1%) respectively; 1079 transfers of two (n = 853; 58.3%) or more than two (n = 226; 15.4%) embryos yielded 366 ongoing pregnancies (33.9%). The ongoing pregnancy rates for the years between 1998 and 2001 were 35.9, 27.9, 31.9 and 31.0% per oocyte retrieval and 38.5, 29.4, 34.1 and 33.2% per transfer. There were no differences in pregnancy rates between any of the years. The average ongoing pregnancy rate (>12 weeks) over the 4 years was 31.5% per started cycle and 33.5% per transfer; the average number of embryos transferred decreased from 2.26 (1998) to 1.79 (2001); the multiple pregnancy and twinning rates dropped from 33.6 and 29.5% (1998) to 18.6 and 16.3% (2001) respectively. CONCLUSIONS: Judicious application of eSET can halve the twinning rate while maintaining the overall pregnancy rate.  相似文献   
998.
BACKGROUND: Mutations of the androgen receptor (AR) gene give rise to a wide array of phenotypic abnormalities. A systematic analysis of the AR gene in patients with 47,XXY has not previously been performed. METHODS: Mutations of the AR gene and expansion of the CAG repeats in exon 1 of the AR gene were studied in 13 patients with Klinefelter's syndrome either with (n = 1) or without (n = 12) spermatogenesis. RESULTS: No abnormalities in the AR gene were detected by single strand conformational polymorphism analysis. The CAG lengths ranged from 17 to 27 (mean +/- SD 22.8 +/- 3.3, median 23) for Klinefelter patients or from 17 to 28 (mean +/- SD 23.2 +/- 2.6, median 23) for control subjects. X-inactivation analysis for the methylation status of the AR gene was performed in seven patients who were heterozygous for CAG repeats of different length, showing that the longer CAG repeat alleles underwent random but more frequent inactivation in five patients and skewed inactivation in two. CONCLUSIONS: An AR gene abnormality does not constitute an important factor for impaired spermatogenesis in patients with Klinefelter's syndrome.  相似文献   
999.
应用FISH、FCM检测APL PML/RARA融合基因及临床应用的研究   总被引:2,自引:0,他引:2  
目的 研究应用荧光原位杂交技术 (FISH)、流式细胞技术 (FCM)检测急性早幼粒细胞白血病 (APL)PML/RARa融合基因及残留白血病细胞的意义。方法 应用CG、M -FISH、FCM对 30例APL患者初发和缓解期的骨髓标本进行分析 ,分别检测t(15 ;17)易位和PML/RARa融合基因及残留白血病细胞的存在。结果 对初发期骨髓标本进行CG和FISH分析发现 ,10 0 %具有t(15 ;17)易位 ,阳性核型占 6 8%~ 10 0 % ,其中有 8例还伴有其他异常 ;10 0 %具有PML/RARa融合基因 ,且阳性中期相的比例高达 96 %~ 10 0 % ;结果具有显著差异 (P <0 0 0 1)。对CR期的骨髓标本进行CG、FISH分析 ,CG为正常核型 ,FISH仍可检出 0 %~ 4 5 %的PML/RARa融合基因。对CR后 12个月的标本进行CG、FISH分析 ,CG均为正常核型 ;FISH仍可检出 0 %~ 37%的PML/RARa融合基因 ,较CR期有所降低。对这 30例APL患者初发期、完全缓解期及完全缓解后 12个月时进行了FCM检测 ,并得出定性结果。完全缓解期检测结果与M -FISH分析一致 ;对完全缓解后 12个月时M -FISH结果进行定性分析发现 30例患者中有 6例为融合基因阴性 ,相应的FCM定性分析结果却发现只有其中的 2例呈现阴性 ,其余 4例仍然为阳性。随访至CR后 2年 ,发现 7例PML/RARa融合基因阳性中期相比例较高 (CG分  相似文献   
1000.
The presence of areas exhibiting a solid/trabecular pattern of growth within an otherwise differentiated thyroid carcinoma represents a source of controversy as regards its proper classification and biologic and prognostic significance. The aim of the current study was to investigate the ultrastructural features of solid/trabecular areas in differentiated thyroid carcinoma and to compare those features with the submicroscopic profile of differentiated, poorly differentiated (insular), and undifferentiated (anaplastic) variants of thyroid cancer. The study series included differentiated carcinoma with solid/trabecular areas (3 cases), conventional papillary carcinoma (4 cases), follicular variant of papillary carcinoma (4 cases), poorly differentiated (insular) carcinoma (3 cases), and undifferentiated (anaplastic) carcinoma (3 cases). It was found that the solid/trabecular areas in differentiated carcinoma and poorly differentiated (insular) carcinoma share similar ultrastructural features and overall retain, even if attenuated, many of the submicroscopic attributes of differentiated carcinomas. In particular, nests of neoplastic cells were observed showing a highly developed cytosecretory apparatus and the presence of numerous abortive/rudimentary follicles, and intercellular and intracellular (intracytoplasmic) lumina/canaliculi of variable morphology. The study supports the hypothesis that the solid/trabecular areas do not merely represent an architectural pattern but rather should be regarded as the expression of a process of reduced differentiation similar to that of poorly differentiated (insular) carcinoma.  相似文献   
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