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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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Ramakrishnan P  Wang W  Wallach D 《Immunity》2004,21(4):477-489
The NF-kappaB-inducing kinase (NIK) induces proteolytic processing of NF-kappaB2/p100 and, hence, the generation of NF-kappaB dimers such as p52:RelB but was suggested not to signal for the processing of IkappaB. Here, we show that although the induction of IkappaB degradation in lymphocytes by TNF is independent of NIK, its induction by CD70, CD40 ligand, and BLyS/BAFF, which all also induce NF-kappaB2/p100 processing, does depend on NIK function. Both CD70 and TNF induce recruitment of the IKK kinase complex to their receptors. In the case of CD70, but not TNF, this process is associated with NIK recruitment and is followed by prolonged receptor association of just IKK1 and NIK. Recruitment of the IKK complex to CD27, but not that of NIK, depends on NIK kinase function. Our findings indicate that NIK participates in a unique set of proximal signaling events initiated by specific inducers, which activate both canonical and noncanonical NF-kappaB dimers.  相似文献   
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OBJECTIVE: To explore the relationship between urinary sodium (the best measure of salt intake), urinary calcium, urinary deoxypyridinoline (DPYR) and bone mass. DESIGN: Cross-sectional study. SETTING: Population based sample of healthy Hobart residents. SUBJECTS: One hundred and fifty-four (M = 34, F = 120) subjects invited to take part from a systematic sample of the electoral roll and a single newspaper advertisement. RESULTS: In both sexes, urinary sodium correlated moderately with urinary DPYR (r = 0.32, P < 0.0001) and urinary calcium (r = 0.37, P < 0.0001). In multivariate analysis, the combination of urinary sodium, total body bone area, age and sex explained 22% of the variation in log-transformed DPYR (P < 0.00001). In univariate analysis, both urinary sodium and urinary DPYR were strongly associated with bone mineral content and bone mineral density at all sites but this association disappeared after adjustment for confounders particularly body weight. CONCLUSIONS: This study has shown that salt intake is associated with markers of bone resorption in a population-based sample of males and females and appears likely to be a risk factor for osteoporosis despite the lack of a demonstrable association between bone mass and a single measure of urinary sodium excretion. Further studies are needed to define the effect of salt intake on bone mass and fractures more clearly. These studies will need to be either longitudinal or interventional in design with repeated measures of urinary sodium so that habitual sodium intake can be accurately assessed and regression dilution bias can be minimised.  相似文献   
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四氯偶氮苯(3,3’,4,4’tetrachloroazobenzene,TCAB)和四氯氧化偶氮苯(3,3’,4,4’tetrachloroazoxybenzene,TCAOB)是在合成氯代或二氯代苯胺类除草剂时生成的污染废弃物。此类除草剂经...  相似文献   
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There are no established guidelines for judging equivalence between inhaled medications. The principles of establishing bioequivalence on the basis of bioavailability and pharmacokinetics may not be applicable to inhaled medications with predominantly topical and minimal systemic effects. For inhaled beta(2)-agonists, the most practical method of showing in vivo therapeutic equivalence is by comparing relative potencies (RPs) of pharmacodynamic effects (bronchodilation and bronchoprotection). A range of doses that includes placebo should be studied in an appropriate design with adequate sample size, and relative potency should be estimated. Hydrofluoroalkane and chlorofluorocarbon salbutamol are bioequivalent for both their bronchodilator (RP, 1.08; 90% confidence interval, 0.95%, 1.23%) and bronchoprotective effects (RP, 1.08; 90% confidence interval, 0.81%, 1.46%) with similar safety profile. Eighteen subjects are required in a cross-over design to demonstrate bronchoprotective bioequivalence with a confidence interval of 67% to 150% for the relative potency (80% power). For salbutamol, this can be achieved with a comparison of 100 and 200 microgram doses. Twelve subjects would suffice for a cumulative dose-response study for bronchodilator bioequivalence. For both outcomes, repeatability and quality control of measurements have to be ensured for an accurate interpretation of the results.  相似文献   
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Adrenomedullin is a recently discovered vasodilatory peptide that has been shown to be a potent activator of adenylate cyclase in a variety of cell systems, including rat mesangial cells. The major aim of the present study was to determine the regulation of rat mesangial cell proliferation (using [3H]thymidine incorporation as an index), apoptosis (using nucleosome-associated cytoplasmic DNA fragmentation as an index) and mitogen-activated protein kinase (MAPK) cascade, specifically extracellular signal-regulated kinase (ERK), jun-amino terminal kinase (JNK) and P38 mitogen-activated protein kinase (P38 MAPK) activities, by adrenomedullin-stimulated cyclic AMP-protein kinase-A pathway. Adrenomedullin increased cAMP levels significantly above basal and the response was inhibited by the adrenomedullin receptor antagonist, adrenomedullin-(22-52). Adrenomedullin also decreased [3H]thymidine incorporation and increased nucleosome-associated cytoplasmic DNA fragmentation, in a concentration-dependent fashion. Both these responses were receptor mediated as, adrenomedullin-(22-52) inhibited these effects. The decrease in proliferation and increase in apoptosis were both mimicked by forskolin, a direct adenylate cyclase activator. Adrenomedullin-mediated decrease in proliferation and increase in apoptosis were inhibited by H89 [[N-[2-((p-bromocinnamyl)amino)ethyl]-5-isoquinolinesulfonamide, hydrochloride]], a potent protein kinase-A inhibitor. Associated with the changes in proliferation and apoptosis, adrenomedullin decreased ERK2 activity, and increased JNK1 and P38 MAPK activities. All these kinase activities, except the increase in JNK1 activity could be simulated using forskolin. In addition, only adrenomedullin-mediated changes in ERK2 and P38 MAPK activities were inhibited by H89 while, adrenomedullin-stimulated JNK1 was not consistently inhibited by the protein kinase-A inhibitor. These results suggest that adrenomedullin might play an important role in mesangial cell turnover and that although adrenomedullin-mediated responses are primarily cAMP-dependent, it does not preclude the involvement of cAMP-independent pathways.  相似文献   
9.
Osteoporosis is a common finding in Turner's syndrome. To test the hypothesis that calcitonin deficiency may contribute to bone mineral loss in Turner's syndrome, we studied basal and calcium-stimulated (2 mg/kg body weight in 5 min) levels of total calcitonin, extractable calcitonin and katacalcin in 15 girls with Turner's syndrome and osteoporosis. Fifteen age-matched healthy girls were studied as controls. Both basal calcitonin (total and extractable) and katacalcin values were not significantly different in patients with Turner's syndrome in comparison with those of the controls. The calcium stimulation test showed a similar "C" cell secretory reserve in both groups. The calculation of delta CT/delta iCa of total and extractable calcitonin and delta KC/delta iCa, which accounts for individual variations in serum ionized calcium increases, did not show any significant difference between girls with Turner's syndrome and controls. We conclude that calcitonin deficiency is not a causative factor of osteoporosis in girls with Turner's syndrome and that in this syndrome long-life estrogen deficiency does not impair "C" cell secretory activity.  相似文献   
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