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991.
Integrin expression in normal and out-of-phase endometria   总被引:7,自引:6,他引:7  
Integrins have recently been proposed as having a major role in endometrial receptivity. Different patterns of integrin expression have been described during the normal endometrial cycle, and the co- expression of several integrins, mainly alpha1, alpha4 and beta3 has been considered as specific to the 'window of implantation'. In the present study 55 infertile patients underwent two endometrial biopsies during a single menstrual cycle. An early biopsy was done on postovulatory days 6-8, and a late biopsy was performed on postovulatory days 10 to 12. Histological dating as well as immunohistochemical evaluation of alpha1, alpha4, beta1, beta3, beta5, alpha(v)beta3 integrin expression and oestrogen and progesterone receptors were determined in all endometrial biopsies. Oestradiol and progesterone serum concentrations in serum were evaluated on the same days of the endometrial samplings. Nine out of the 55 midluteal biopsies (16.4%) showed out-of-phase endometria, but all biopsies were in phase in the late luteal phase. Differences in integrin expression between in- and out-of-phase biopsies were observed only for alpha(v)beta3 integrin glandular expression during the midluteal phase. Alpha(v)beta3 integrin glandular expression was found in all late luteal phase biopsies. Alpha(v)beta3 expression was closely correlated with histological maturation of the endometrium appearing suddenly at postovulatory day 6-7 and being expressed by all endometria dated as postovulatory day > or = 8, irrespective of midluteal endometrial biopsies being in phase or out of phase. No differences in integrin expression were detected between patients with or without endometriosis or between patients who became spontaneously pregnant and those who did not. In conclusion, further studies are necessary before patterns of integrin expression may offer an alternative to predict uterine receptivity and implantation potential.   相似文献   
992.
This randomized controlled trial assessed which of three low-intensity ovulation induction protocols was associated with the highest rate of cycle completion among infertile women undergoing intrauterine insemination (IUI) with their husband's spermatozoa. Sixty-three women aged < or = 42 years with normospermic partners participated in the study. The primary diagnosis of infertility was unexplained in 89% of subjects, endometriosis in 6% and tubal factor in 5%. Women were assigned to three groups according to recombinant FSH dosage: group A received two ampoules (75 IU FSH per ampoule) on cycle day 4, and one ampoule on days 6 and 8 (total four ampoules); group B received two ampoules on days 4, 6 and 8 (total six ampoules); group C received two ampoules on days 4, 6, 8 and 10 (total eight ampoules). Daily ultrasound investigations began on cycle day 9-12 and human chorionic gonadotrophin (HCG) 5000 IU was administered when one or two follicles > or = 18 mm were seen. IUI was scheduled for the next day. HCG was given and/or ovulation shown to have occurred in 88 of 109 cycles attempted (81%) with no differences among the three dose groups. Two singleton pregnancies occurred (2.3% per ovulatory cycle and 1.8% per cycle start). There were no significant differences among the three regimes in terms of cycle parameters, suggesting that an individualized and more intensive approach to ovarian stimulation is necessary for many women with unexplained infertility.   相似文献   
993.
Previous studies have shown that severe ovarian hyperstimulation syndrome (OHSS) is secondary to circulatory dysfunction due to the simultaneous occurrence of increased vascular permeability and marked arteriolar vasodilation which lead to an intense homeostatic stimulation of the renin-aldosterone and sympathetic nervous systems and antidiuretic hormone (ADH). In the present report, we have investigated the correlation between changes in haematocrit concentration, and white blood cell (WBC) and platelet counts and the severity of OHSS, as assessed by these markers of effective intra- arterial blood volume, in a series of 50 patients. In comparison with recovery values (4-5 weeks after hospital discharge), OHSS patients showed arterial hypotension, tachycardia, oliguria, very high plasma concentrations of renin, aldosterone, norepinephrine and ADH, and increased mean haematocrit values and WBC and platelet counts. The haematocrit concentration values were directly related to the plasma concentrations of vasoactive substances (plasma renin activity, aldosterone, norepinephrine and ADH) during OHSS (P < 0.001). In contrast, no correlation was evident between WBC or platelet counts and neurohormonal measurements during the syndrome. It is concluded that haematocrit, but not WBC or platelet counts, can act as a biological marker of the severity of OHSS as indicated by plasma measurement of volume-dependent endogenous vasoactive substances.   相似文献   
994.
A simple and objective approach to identifying human round spermatids   总被引:2,自引:9,他引:2  
Although round spermatids have been studied extensively using staining techniques and electron microscopy, little information is available about their appearance in living conditions. We describe a method of collecting and identifying round spermatids from ejaculates and testicular biopsies. The validity of the selection procedure was confirmed by fluorescence in-situ hybridization. Based on cell size, morphological characteristics of nucleus and cytoplasm, and on the nucleus/cytoplasm ratio, we harvested a population of cells that was 84% haploid. This procedure can be applied to select spermatids for clinical or research purposes.   相似文献   
995.
996.
A simplified method for the preparation and long-term cultivation of granulosa-luteal cells in serum-free medium is described. The cells were harvested from women undergoing in-vitro fertilization, enriched by sedimentation and dissociated by enzymatic treatment. We demonstrated, by introducing a synthetic serum replacement (SSR2), that these primary cell cultures cultivated in monolayers on an extracellular matrix may be used in experiments exceeding 7 days with low cell loss and cell death. No adverse effect on progesterone production was found. There was a high diversity in progesterone production between cells from individual patients. After several days in culture, the cells were challenged with human chorionic gonadotrophin which revived the rapidly decreasing progesterone production. We were unable to demonstrate an increase in cell number after 7 days of cultivation when the cells were grown in medium supplemented with either serum or SSR2. The mitogens epidermal growth factor and basic fibroblast growth factor had no influence on proliferation. We also found that the present method prevents leukocyte contamination in the granulosa-luteal cell cultures. Compared with the common method based on the enrichment of granulosa-luteal cells on a density gradient (Ficoll/Percoll), this method saves time, labour and expense, in addition to augmenting purity.   相似文献   
997.
HPRT-APRT-deficient mice are not a model for lesch-nyhan syndrome   总被引:4,自引:0,他引:4  
Complete hypoxanthine-guanine phosphoribosyl-transferase (HPRT) deficiency in humans results in the Lesch-Nyhan syndrome which is characterized, among other features, by compulsive self-injurious behavior. HPRT-deficient mice generated using mouse embryonic stem cells exhibit none of the behavioral symptoms associated with the Lesch- Nyhan syndrome. Administration of drugs that inhibit adenine phosphoribosyltransferase (APRT) in HPRT-deficient mice has produced the suggestion that deficiency of APRT in combination with HPRT- deficiency in mice may lead to self-mutilation behavior [C.L. Wu and D.W. Melton (1993) Nature Genet. 3, 235-240]. To test this proposition, we bred HPRT-APRT-deficient mice. Although the doubly-deficient mice excrete adenine and its highly insoluble derivative, 2,8- dihydroxyadenine, which are also associated with human APRT deficiency, additional abnormalities or any self-injurious behavior were not detected. Thus, APRT-HPRT-deficient mice, which are devoid of any purine salvage pathways, show no novel phenotype and are not a model for the behavioral abnormalities associated with the Lesch-Nyhan syndrome as previously suggested.   相似文献   
998.
999.
The performance of hysterosalpingo contrast sonography (Hy Co Sy) as a first-line, outpatient investigation of tubal patency was examined in 500 consecutive, infertile women, at one centre. Hy Co Sy was completed in 463 (92.6%) cases, using a galactose microbubble contrast agent (Echovist-200) and transvaginal sonography. Initial plain scanning identified adnexal pathology in 198 women (39.6%). Examination with Echovist was attempted for 905 tubes and only 67 (7.4%) were not assessable; after the first 100 women this decreased to 35 tubes (4.8%). A sonographic appearance compatible with blocked tubes was found on 118 (14.1%) occasions but it was also possible to identify variations in the appearance/filling/spilling patterns of individual tubes which increased the number assessed as abnormal to 193 (23.0%). Comparison with laparoscopy and dye chromopertubation findings from the past three years was possible for 185 (37%) women, representing 282 tubes, which gave Hy Co Sy an overall concordance rate of 85.8%, sensitivity of 90.4%, specificity of 70.3%, positive predictive value of 91.2% and negative predictive value of 68.2%. Some 51.0% of women described only mild discomfort and there were no significant postprocedure complications. Hy Co Sy appears to be an acceptable first- line screen and may select out women in whom more invasive investigations are likely to reveal pathology.   相似文献   
1000.
Linkage analysis of candidate regions for coeliac disease genes   总被引:5,自引:0,他引:5  
A strong HLA association is seen in coeliac disease [specifically to the DQ(alpha1*0501,beta1*0201 heterodimer], but this cannot entirely account for the increased risk seen in relatives of affected cases. One or more genes at HLA-unlinked loci also predispose to coeliac disease and are probably stronger determinants of disease susceptibility than HLA. A recent study has proposed a number of candidate regions on chromosomes 6p23 (distinct from HLA), 6p12, 3q27, 5q33.3, 7q31.3, 11p11, 15q26, 19p13.3, 19q13.1, 19q13.4 and 22cen for the location of a non-HLA linked susceptibility gene. We have examined these regions in 28 coeliac disease families by linkage analysis. There was excess sharing of chromosome 6p markers, but no support for a predisposition locus telomeric to HLA. No significant evidence in favour of linkage to coeliac disease was obtained for chromosomes 3q27, 5q33.3, 7q31.3, 11p11, 19p13.3, 19q13.1, 19q13.4 or 22cen. There was, however, excess sharing close to D15S642. The maximum non-parametric linkage score was 1.99 (P = 0.03). Although the evidence for linkage of coeliac disease to chromosome 15q26 is not strong, the well established association between coeliac disease and insulin dependent diabetes mellitus, together with the mapping of an IDDM susceptibility locus (IDDM3) to chromosome 15q26, provide indirect support for this as a candidate locus conferring susceptibility to coeliac disease in some families.   相似文献   
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