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81.
To assess the risk of miscarriage after in-vitro fertilization(IVF) with respect to age, cause of infertility, ovarian morphologyand treatment regimen, a retrospective analysis was performedof the first 1060 pregnancies conceived between June 1984 andJuly 1990 as a result of 7623 IVF cycles. Superovulation inductionwas achieved with human menopausal gonadotrophin (HMG) and/orpurified follicle stimulating hormone (FSH) together with eitherclomiphene citrate or the gonadotrophin hormone-releasing hormone(GnRH) agonist buserelin, the latter either as a short ‘flare’regimen or as a ‘long’ regimen to induce pituitarydesensitization. There were 282 spontaneous abortions (26.6%)and 54 ectopic pregnancies (5.1%). The mean age of women withongoing pregnancies was 32.2 (SD 3.9) years compared with 33.2(SD 4.1) years in those who miscarried, which were significantlydifferent (P = 0.008). There was no relation between the miscarriagerate and the indication for IVF. The miscarriage rate was 23.6%in women with normal ovaries compared with 35.8% in those withpolycystic ovaries [P = 0.0038, 95% confidence interval (CI)4.68–23.10%]. There was no difference in the miscarriagerate between treatment with HMG or FSH. Women whose ovarieswere normal on ultrasound were just as likely to miscarry ifthey were treated with clomiphene or with the long buserelinprotocol. Those with polycystic ovaries, however, had a significantreduction in the rate of miscarriage when treated with the longbuserelin protocol, 20.3% (15/74), compared with clomiphenecitrate, 47.2% (51/108) (P = 0.0003, 95% CI 13.82–40.09%).  相似文献   
82.
Population studies of the fragile X: a molecular approach.   总被引:11,自引:1,他引:11       下载免费PDF全文
The fragile X mutation can now be recognised by a variety of molecular techniques. We report a pilot screening survey of a population of children with mental impairment in which we used Southern blotting methods to detect the fragile X mutation, augmented by cytogenetic studies on children whose phenotype suggested a possible chromosome abnormality. There were 873 children with special educational needs in our survey and 310 fulfilled our criteria for testing. A sample was obtained from 254, of whom four were found to have a full fra(X) mutation (delta L) and none to have a premutation. The number of CGG repeats in our population of X chromosomes was measured by PCR analysis and the genotype at the closely linked polymorphic locus FRAXAC1 established. The distribution of CGG repeat numbers was very similar to that of the control population reported by Fu et al and the distribution of FRAXAC1 alleles almost identical to that of the control population reported by Richards et al. Among the non-fragile X chromosomes, we found a very significant correlation between the size of the CGG repeat and the FRAXAC1 genotype. There was a dearth of A and D genotypes in subjects with a small number of CGG repeats and an excess of the A genotype in those with a large number of CGG repeats. These observations are considered in the light of the reported disequilibrium between the A (and possibly also the D) genotype and the fra(X) mutation.  相似文献   
83.
The mechanism underlying the chronic and intermittent course of rheumatoid arthritis is not elucidated. In the present study, the role of interleukin 1 (IL-1) was investigated in exacerbations of antigen-induced arthritis in mice. A flare-up of smoldering inflammation (weeks 3 to 4 of antigen-induced arthritis) was inducible by injection of a small amount of methylated bovine serum albumin into the hypersensitive knee joint. Immunohistochemistry showed IL-1 expression in the synovial lining layer and in focal areas of the inflamed synovium during the flare-up. IL-1 was also measured in 1-hour culture supernatant of synovial tissue taken during the flare-up by a bioassay. The expression of both immunoreactive and bioactive IL-1 in the hypersensitive joint peaked around 6 hours after antigen (2 micrograms of methylated bovine serum albumin) injection and declined thereafter. Antigen rechallenge induced an acute joint swelling of the arthritic joint but not in the naive joint of the sensitized mouse, yet synovia of both joints produced IL-1 after antigen injection. Remarkably, a single intravenous injection of rabbit anti-IL-1 alpha and -beta antibodies 1 hour before antigen rechallenge neutralized IL-1 in the joint. Anti-IL-1 treatment significantly reduced the antigen-induced joint swelling (30 to 40%) but did not affect the profound influx of polymorphonuclear cells in the onset of the exacerbation. However, a profound relief of the inflammation (synovitis) was obtained by IL-1 blockade on day 4 of the exacerbation. Chondrocyte proteoglycan synthesis was markedly suppressed in the antigen-challenged naive knee joints suggesting that this was a direct IL-1 effect as the inflammation was insignificant. Anti-IL-1 treatment was able to maintain chondrocyte proteoglycan synthesis in the antigen-rechallenged joint, which was highly suppressed in the control group. Furthermore, the enhanced proteoglycan breakdown in the antigen-rechallenged joints was significantly decreased in the anti-IL-1 group. We concluded that IL-1 is an important mediator in exacerbations of murine arthritis, and amelioration of cartilage pathology was obtained with anti-IL-1 antibody treatment.  相似文献   
84.
The frequency of non-clonal structural and numerical chromosome aberrations in peripheral blood lymphocytes of 51 patients with MDS and 37 age-matched hematologically normal subjects is assessed. The frequency of aneuploid cells (p less than 0.001) and of structural aberrations (p less than 0.005) was significantly higher in MDS patients than in normal subjects, but showed no relationship with FAB type or with the presence of clonal karyotype abnormalities in the bone marrow. Exchange configurations were only observed in MDS patients (27.5%). The data also suggest that there may be an association between high peripheral blood aberration levels and rapidly progressive disease. This may indicate increased mutagen sensitivity and have implications for treatment.  相似文献   
85.

Background  

The Internet has been increasingly utilized in biomedical research. From online searching for literature to data sharing, the Internet has emerged as a primary means of research for many physicians and scientists. As a result, Web-based surveys have been employed as an alternative to traditional, paper-based surveys. We describe DADOS-Survey, an open-source Web-survey application developed at our institution that, to the best of our knowledge, is the first to be compliant with the Checklist for Reporting Results of Internet E-Surveys (CHERRIES). DADOS-Survey was designed with usability as a priority, allowing investigators to design and execute their own studies with minimal technical difficulties in doing so.  相似文献   
86.
The CA 125 tumour-associated antigen: a review of the literature   总被引:11,自引:1,他引:11  
CA 125 is an antigenic determinant on a high-molecular-weight glycoprotein recognized by a monoclonal antibody which was raised using an ovarian cancer cell line as an immunogen. During the last 5 years the studies reviewed in this paper have provided information concerning the nature, distribution and clinical significance of CA 125. The CA 125 determinant is expressed by epithelial ovarian tumours and various other pathological and normal tissues of Müllerian origin. The function of the glycoprotein expressing CA 125 remains unclear but the distribution of the antigen suggests that it may have a physiological role. The highest serum levels of CA 125 are found in ovarian cancer patients, but elevation of serum CA 125 may also be associated with other malignancies and benign and physiological states, including pregnancy, endometriosis and menstruation. Despite limitations of sensitivity and specificity serum CA 125 estimation is of clinical value in the pre-operative diagnosis and monitoring of ovarian malignancy and may be a prognostic indicator for this disease. The role of CA 125 in screening for early-stage ovarian cancer is currently under investigation. Recent reports suggest that serum CA 125 measurement may also be of value as a prognostic indicator in endometrial cancer and as a reflection of disease status in advanced endometriosis.  相似文献   
87.
Cyclin B3 has been conserved during higher eukaryote evolution as evidenced by its identification in chicken, nematodes, and insects. We demonstrate that Cyclin B3 is present in addition to Cyclins A and B in mitotically proliferating cells and not detectable in endoreduplicating tissues of Drosophila embryos. Cyclin B3 is coimmunoprecipitated with Cdk1(Cdc2) but not with Cdk2(Cdc2c). It is degraded abruptly during mitosis like Cyclins A and B. In contrast to these latter cyclins, which accumulate predominantly in the cytoplasm during interphase, Cyclin B3 is a nuclear protein. Genetic analyses indicate functional redundancies. Double and triple mutant analyses demonstrate that Cyclins A, B, and B3 cooperate to regulate mitosis, but surprisingly single mutants reveal that neither Cyclin B3 nor Cyclin B is required for mitosis. However, both are required for female fertility and Cyclin B also for male fertility.  相似文献   
88.
To determine whether donated blood samples in African countries could be pooled, then tested for the presence of human immunodeficiency virus (HIV) antibodies with a single test without loss of accuracy, a single test on five pooled samples was used, followed by individual testing of positive pools. This resulted in no loss of either sensitivity or specificity. Pooling 10 samples resulted in a loss of sensitivity for low antibody titre specimens. Pooling reduced the costs of screening by 70% and time needed for analysis. It is concluded that pooling of five samples for HIV screening may result in a substantial reduction in costs; in countries where the prevalence of HIV is higher than the 2-3% found in Zimbabwean donors, however, savings may not be as great.  相似文献   
89.
Chlamydial pneumonitis induced in newborn guinea pigs.   总被引:1,自引:0,他引:1       下载免费PDF全文
One- to three-day-old guinea pigs were inoculated intranasally with the chlamydial agent of guinea pig inclusion conjunctivitis. Physical signs of infection included a marked increase in respiration rate on days 5 to 10 of infection and radiographic evidence of pneumonia on day 6. When animals were killed at various times after infection and lung tissue was examined by histopathology, evidence of pneumonia was found beginning on day 4 and lasting as long as day 12, with maximal pathological changes on days 6 to 8. The pneumonia was generally unilateral and consisted of an acute inflammatory component in the bronchioles with granulocytes in both the lumen and the wall of the bronchioles and an interstitial and intra-alveolar mononuclear infiltrate in the parenchyma of the lung. Chlamydial antigen was detected in the bronchial epithelial cells by immunoperoxidase staining, and the guinea pig inclusion conjunctivitis organism was isolated from lung tissue on days 6 to 9. No other significant bacteria were isolated from lung tissue or seen on gram stains of lung sections. Both immunoglobulin M and immunoglobulin G serum antibodies to the guinea pig inclusion conjunctivitis agent were detected as early as day 8 and reached peak levels on day 12. The infection was apparently self-limiting. This model presents the opportunity to investigate pathophysiological and immunological aspects of chlamydial respiratory infections in a neonatal animal.  相似文献   
90.
BACKGROUND: The etiology of IgA nephropathy (IgAN), the most common form of glomerulonephritis in the world, remains an enigma. Episodes of nephritis are frequently preceded by acute viral respiratory syndromes, but few experimental models associated with acute viral infection exist. EXPERIMENTAL DESIGN: An animal model of IgAN involving Sendai virus, a rodent parainfluenza virus similar to many human respiratory viruses, is described. Mice were either naturally infected or chronically mucosally immunized with virus. Immunized mice were then challenged intravenously with various physical forms of antigen to simulate viremia or antigenemia secondary to acute viral exposure. Twenty-four hours after challenge of immunized mice or 10 days after natural infection, mice were sacrificed. Anti-viral antibody titers, glomerular immune deposits, and glomerular function were evaluated. RESULTS: Chronic mucosal immunization of mice with Sendai virus resulted in a vigorous serum IgA (and IgG) anti-viral immune response, associated with comparable degrees of IgA, IgG, IgM, and antigen deposits in the glomeruli of both challenged and unchallenged mice. Only immunized, challenged mice developed significant proteinuria and hematuria. Neither deposits nor glomerular dysfunction was seen in controls. The physical form of antigen was important for altered glomerular function; although immunized mice challenged with either live or dead virions had a high incidence of hematuria, mice challenged with purified viral glycoproteins did not, even though all mice exhibited comparable immune deposits. Significant deposits of C3 were not present and were not required for glomerular injury. Finally, naturally infected mice exhibited a milder form of IgAN without hematuria. CONCLUSIONS: The experimental conditions for acute exposure to a natural viral respiratory pathogen of mice leading to IgAN are described. This model may be useful both to probe infection-related IgAN, and to facilitate the understanding of the various mechanisms responsible for IgAN.  相似文献   
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