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41.
Uterine myomata and outcome of assisted reproduction   总被引:5,自引:8,他引:5  
The aim of this work was to study the effect of uterine myomata on the implantation rate and outcome in in-vitro fertilization (IVF) and intracytoplasmic sperm injection (ICSI). Among 406 patients, 51 (12.6%) were found to have uterine corporeal myomata. Twelve patients were excluded from the study as they had large myomata, submucous myomata or intramural myomata encroaching on the cavity. These patients were advised to have myomectomy before being enrolled in the IVF/ICSI programme. The remaining patients (n = 39) were sorted according to the number, site and size of the myomata as assessed by transvaginal sonography. Three patients had more than one myoma. Most of the myomata were subserous (72.7%) and the mean diameter of the myomata was 3.5 +/- 0.9 cm. A control group (n = 367) was chosen with normal uteri and no history of uterine reconstruction surgery. The mean age of myoma patients was 34.7 +/- 3.6 years as compared to 34.0 +/- 4.4 years in the control group. The age, period of infertility, body mass index, duration and number of human menopausal gonadotrophin ampoules needed for stimulation, oestradiol levels, number of oocytes retrieved and the fertilization rate were not significantly different in the myoma patients compared to the control group. Fifteen myoma patients (38.5%) subsequently showed one or more pregnancy sacs on ultrasonography of which three (20%) spontaneously aborted during the first trimester and two (13.3%) had preterm labour, as compared to 123 (33.5%), 19 (15.5%) and nine (7.3%) respectively, among the control group (P = 0.27, 0.33 and 0.21). In conclusion, uterine corporeal myomata, not encroaching on the cavity and <7 cm in mean diameter, do not affect the implantation or miscarriage rates in IVF or ICSI.   相似文献   
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The objective of this work was to study the effects of plyometric training on the mechanical properties of the ankle joint in humans. Changes in the mechanical parameters of this musculo-articular structure were quantified with the aid of a sinusoidal perturbation technique. This technique allowed the expression of the mechanical impedance of the musculo-articular system in terms of stiffness, viscosity and inertia. Measurements were performed under passive conditions and when the subject performed plantar flexion. A 7-week period of training induced a decrease in the slope of the relationship between stiffness and plantar flexion torque, whereas passive stiffness was increased. A slight decrease in viscosity and an invariability in inertia were also found. These results are interpreted in terms of the possible adaptations of the musculo-articular structure and ultrastructure involved in the performance of plantar flexion. Accepted: 11 April 1997  相似文献   
44.
Germline mutations of the CDKN2 gene in UK melanoma families   总被引:4,自引:1,他引:4  
Germline mutations in CDKN2 on chromosome 9p21, which codes for the cyclin D kinase inhibitor p16, and more rarely, mutations in the gene coding for CDK4, the protein to which p16 binds, underlie susceptibility in some melanoma families. We have sequenced all exons of CDKN2 and analysed the CDK4 gene for mutations in 27 UK families showing evidence of predisposition to melanoma. Five different germline mutations in CDKN2 were found in six families. Three of the mutations (Met53Ile, Arg24Pro and 23ins24) have been reported previously. We have identified two novel CDKN2 mutations (88delG and Ala118Thr) which are likely to be associated with the development of melanoma, because of their co-segregation with the disease and their likely functional effect on the CDKN2 protein. In binding assays the protein expressed from the previously described mutation, Met53Ile, did not bind to CDK4/CDK6, confirming its role as a causal mutation in the development of melanoma. Ala118Thr appeared to be functional in this assay. Arg24Pro appeared to bind to CDK6, but not to CDK4. No mutations were detected in exon 2 of CDK4, suggesting that causal mutations in this gene are uncommon. The penetrance of these mutant CDKN2 genes is not yet established, nor is the risk of non-melanoma cancer to gene carriers.   相似文献   
45.
Prenatal cytogenetic analysis of 71 fetuses conceived by intracytoplasmic sperm injection (ICSI) resulted in the detection of nine (12.7%) chromosome aberrations including two cases of 47,XXY, four cases involving a 45,X cell line and three autosomal trisomies. Molecular analysis of the parental origin of the deleted or supernumerary chromosome was performed by using polymorphic microsatellite markers. Six cases involving a sex chromosome abnormality were found to be of paternal origin while the two trisomic cases that could be analysed were of maternal origin. Two cases involved the same infertile couple who had two consecutive ICSI pregnancies terminated because of a chromosome abnormality. The replaced embryos in both cases originated from a single batch of ICSI fertilized oocytes of which part was used to initiate the first pregnancy and part was cryopreserved and used to initiate the second pregnancy.   相似文献   
46.
47.
Summary The early responses of cat retinal ganglion cells to axotomy have been examined using neurofibrillar and Nissl-stained wholemounts. We were interested to learn whether the enhanced neurofilament expression, seen in a number of neuronal systems, was also present in different neuronal populations of the cat retina and could be used to study the distribution of these cells. We found that beta ganglion cells degenerate very rapidly after axotomy with the nuclei becoming pyknotic within a few days. Few beta cells showed increased neurofibrillar staining of the dendrites. The cell body degenerated prior to any visible degenerative changes in the axon. A proportion of the alpha and gamma ganglion cells degenerated in the first two to three weeks after axotomy. The alpha cells underwent markedly enhanced neurofibrillar staining of their dendrites prior to degeneration. The Nissl material of the cell bodies diminished as the cells degenerated but we have not observed pyknotic nuclei. The dendritic trees of some axotomised gamma cells were also revealed by the neurofibrillar stain three weeks after axotomy. These results show that retinal ganglion cells do not degenerate by a dying back process. We suggest that the rapid degeneration of the beta ganglion cell population comes about by excitotoxic cell death, a consequence of their large glutamatergic input from bipolar cells. The degenerating beta ganglion cells have the morphological appearance of cells undergoing apoptosis.  相似文献   
48.
49.
Monoclonal antibodies directed against sheep erythrocytes of the isotypes IgG1, IgG2b and IgG2a were used to analyze the specificity of antibody-induced suppression of the immune response. It was first shown that all monoclonals reacted against different antigenic determinants and they all suppressed the immune response to sheep erythrocytes when given shortly after the antigen to more than 50% as compared to 90-96% inhibition obtained with a polyclonal antiserum. Increasing the doses of monoclonals did not increase suppression. However, two different monoclonals administered together caused an additive, but not a synergistic inhibitory effect. No enhancement of the immune response was observed with any of the Ig classes tested. These findings show that four different antigenic determinants on sheep erythrocytes induced the synthesis of corresponding antibodies, with little or no signs of a dominant determinant. Passively administered monoclonal antibodies, even at supraoptimal doses, never suppressed the immune response to the same extent as a polyclonal antiserum, suggesting that each monoclonal only suppressed the synthesis of the corresponding antibody and did not affect antibody synthesis to other determinants.  相似文献   
50.
The aims of this work were to measure the accuracy of one continuous speech recognition product and dependence on the speaker's gender and status as a native or nonnative English speaker, and evaluate the product's potential for routine use in transcribing radiology reports. IBM MedSpeak/Radiology software, version 1.1 was evaluated by 6 speakers. Two were nonnative English speakers, and 3 were men. Each speaker dictated a set of 12 reports. The reports included neurologic and body imaging examinations performed with 6 different modalities. The dictated and original report texts were compared, and error rates for overall, significant, and subtle significant errors were computed. Error rate dependence on modality, native English speaker status, and gender were evaluated by performing ttests. The overall error rate was 10.3 +/- 3.3%. No difference in accuracy between men and women was found; however, significant differences were seen for overall and significant errors when comparing native and nonnative English speakers (P = .009 and P = .008, respectively). The speech recognition software is approximately 90% accurate, and while practical implementation issues (rather than accuracy) currently limit routine use of this product throughout a radiology practice, application in niche areas such as the emergency room currently is being pursued. This methodology provides a convenient way to compare the initial accuracy of different speech recognition products, and changes in accuracy over time, in a detailed and sensitive manner.  相似文献   
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