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Chaoui R Heling KS Sarioglu N Schwabe M Dankof A Bollmann R 《American journal of obstetrics and gynecology》2005,192(1):257-263
OBJECTIVE: The right subclavian artery arises normally as the first vessel from the brachiocephalic artery of the aortic arch. An aberrant right subclavian artery arises as a separate vessel from the aortic isthmus and crosses to the right, behind the trachea. This variant is present in <1% of the normal population; however, in subjects with Down syndrome, an incidence between 19% and 36% was reported. The purpose of this study was to assess the possibility of the detection of an aberrant right subclavian artery in fetuses with Down syndrome. STUDY DESIGN: Fourteen consecutive fetuses with prenatally detected Down syndrome were examined between 18 and 33 weeks of gestation. The presence of an aberrant right subclavian artery was determined by visualization of the transverse 3-vessel trachea view of the upper thorax with color Doppler ultrasonography. RESULTS: The right subclavian artery was visualized in 100% of fetuses (14/14) with Down syndrome. An aberrant right subclavian artery was identified in 35.7% of trisomy 21 fetuses (5/14). In 1 fetus, the aberrant right subclavian artery was the only abnormal ultrasound finding. In 3 fetuses, an aberrant right subclavian artery was associated with an intracardiac echogenic focus plus additional extracardiac markers. In the fourth fetus, an aberrant right subclavian artery was associated with an atrioventricular septal defect. All 9 fetuses with Down syndrome with a normal origin of the right subclavian artery had additional cardiac and/or extracardiac abnormalities. In 12 cases, pregnancy was terminated; 2 fetuses were live born. CONCLUSION: This preliminary study suggests that the in utero identification of an aberrant right subclavian artery may be a new ultrasound marker to be found in fetuses with Down syndrome. Further studies are required to assess the incidence of aberrant right subclavian artery in normal fetuses. 相似文献
45.
Dimeric inhibins, activins, and follistatin (FS) were all initially characterized as reproductive endocrine hormones that regulate follicle-stimulating hormone (FSH) secretion. This model, however, has expanded under the weight of current medical evidence. Activin appears to play a central auto/paracrine role in reproductive and nonreproductive tissues. Inhibin and FS each have important counterregulatory functions in activin signaling. With reproductive aging, inhibin B declines along with the follicular pool and disturbs the dynamics of the normal menstrual cycle of midreproductive age. The loss of inhibin restraint of FSH secretion appears to be the initiating endocrine event that leads to menstrual cycle shortening and some of the hormonal unpredictability of the late reproductive years. It may also be related to the decline in fertility that occurs in reproductive aging. In men, inhibin B is an excellent marker for gonadal competence, and the decline of inhibin B with age reflects decreased gonadal reserve in both sexes. Circulating activin increases with aging, but its effect on reproduction in women and men is not clear. FS does not appear to change greatly with aging in men or women. The age-related fluctuations in this delicately balanced regulatory triad influence reproductive capacity and the sequelae of chronological aging. Elucidation of the molecular pathways responsible for the action of these hormones may allow closer integration with their current conceptual roles in aging. 相似文献
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Canadian Journal of Anesthesia/Journal canadien d'anesthésie - 相似文献
47.
Naik RG Beckers C Wentwoord R Frenken A Duinkerken G Brooks-Worrell B Schloot NC Palmer JP Roep BO 《Journal of autoimmunity》2004,23(1):55-61
T-cell mediated autoimmune beta-cell destruction is an important component of type 1 diabetes (T1D) and insulin is a critical antigen recognized by autoreactive T-cells. The aim of this study was to investigate the precursor frequency of insulin reactive T-cells in type 1 diabetes. We studied 19 T1D patients, 12 age-matching non-diabetic healthy siblings and 12 non-diabetic healthy parents. Limiting dilution analysis (LDA) was performed to insulin and tetanus toxoid (TT). A progressive decrease in the number of negative cultures at increasing cell concentrations that is represented by a low goodness-of-fit (GoF, low Chi-square), was seen with the TT response in all three groups; precursor frequencies and GoF were similar in patients, siblings, and parents. Reactivity to insulin, however, showed low precursor frequencies in patients and siblings and the LDA to insulin demonstrated dramatic decreases in the number of positive cultures at higher cell concentrations leading to a high GoF in patients and siblings compared to parents. This saw-toothed pattern of reactivity to insulin is indicative of multiple hit kinetics and implies that the response is regulated. Consequently the precursor frequency of insulin autoreactive cells in patients and their siblings is probably much higher than calculated. 相似文献
48.
Magnetic resonance imaging of the breast prior to biopsy 总被引:15,自引:0,他引:15
Bluemke DA Gatsonis CA Chen MH DeAngelis GA DeBruhl N Harms S Heywang-Köbrunner SH Hylton N Kuhl CK Lehman C Pisano ED Causer P Schnitt SJ Smazal SF Stelling CB Weatherall PT Schnall MD 《JAMA》2004,292(22):2735-2742
Context Breast magnetic resonance imaging (MRI) has been shown to have high sensitivity for cancer detection and is increasingly used following mammography to evaluate suspicious breast lesions. Objective To determine the accuracy of breast MRI in conjunction with mammography for the detection of breast cancer in patients with suspicious mammographic or clinical findings. Design, Setting, and Patients Prospective multicenter investigation of the International Breast MR Consortium conducted at 14 university hospitals in North America and Europe from June 2, 1998, through October 31, 2001, of 821 patients referred for breast biopsy for American College of Radiology category 4 or 5 mammographic assessment or suspicious clinical or ultrasound finding. Interventions MRI examinations performed prior to breast biopsy; MRI results were interpreted at each site, which were blinded to pathological results. Main Outcome Measures Area under the receiver operating characteristic curve (AUC), sensitivity, and specificity of breast MRI. Results Among the 821 patients, there were 404 malignant index lesions, of which 63 were ductal carcinoma in situ (DCIS) and 341 were invasive carcinoma. Of the 417 nonmalignant index lesions, 366 were benign, 47 showed atypical histology, and 4 were lobular carcinoma in situ. The AUC pooled over all institutions was 0.88 (95% confidence interval [CI], 0.86-0.91). MRI correctly detected cancer in 356 of 404 cancer cases (DCIS or invasive cancer), resulting in a sensitivity of 88.1% (95% CI, 84.6%-91.1%), and correctly identified as negative for cancer 281 of 417 cases without cancer, resulting in a specificity of 67.7% (95% CI, 62.7%-71.9%). MRI performance was not significantly affected by mammographic breast density, tumor histology, or menopausal status. The positive predictive values for 356 of 492 patients was 72.4% (95% CI, 68.2%-76.3%) and of mammography for 367 of 695 patients was 52.8% (95% CI, 49.0%-56.6%) (P<.005). Dynamic MRI did not improve the AUC compared with 3-dimensional MRI alone, but the specificity of a washout pattern for 123 of 136 patients without cancer was 90.4% (95% CI, 84%-95%). Conclusions Breast MRI has high sensitivity but only moderate specificity independent of breast density, tumor type, and menopausal status. Although the positive predictive value of MRI is greater than mammography, MRI does not obviate the need for subsequent tissue sampling in this setting. 相似文献
49.
Preauricular sinuses (ear pits) are common congenital abnormalities. Usually asymptomatic, they manifest as small dells adjacent to the external ear near the anterior margin of the ascending limb of the helix, most frequently on the right side. Preauricular sinuses can be either inherited or sporadic. When inherited, they show an incomplete autosomal dominant pattern with reduced penetrance and variable expression. They may be bilateral, increasing the likelihood of being inherited, in 25-50% of cases. Preauricular sinuses are features of other conditions or syndromes in 3-10% of cases, primarily in association with deafness and branchio-oto-renal (BOR) syndrome. When other congenital anomalies coexist with these sinuses, auditory testing and renal ultrasound should be considered. Sinuses may become infected, most commonly with gram-positive bacteria, in which case their exudates should be cultured and appropriate antibiotics administered. Recurrent infection is a clear indication for complete excision and provides the only definitive cure. Recurrence rates after surgery range from 9% to 42%. Meticulous excision by an experienced head and neck surgeon minimizes the risk of recurrence. 相似文献
50.
Exercise therapy in women who have had breast cancer: design of the Sheffield women's exercise and well-being project 总被引:4,自引:0,他引:4
Recovering from cancer treatment can be a difficult experience, both physically and psychologically. This paper describes a randomized controlled trial that evaluates the effects of exercise therapy upon quality of life in 120 women who have had breast cancer. To facilitate behaviour change, exercise counselling is also included as an integral component in the exercise therapy intervention. Participants are randomized to one of three groups: exercise therapy, body conditioning (placebo control) or a normal care control group. The supervised exercise therapy and body conditioning sessions take place 3 times per week for 8 weeks. Outcome measures include quality of life, physical self-perceptions, depression, satisfaction with life, exercise behaviour, aerobic capacity and percentage body fat. All outcomes are assessed at baseline, 4 weeks during the intervention and at the end of the 8-week intervention. Follow-up assessments of outcomes take place at 3 and 6 months post-intervention. As the number of women surviving breast cancer is increasing and cancer treatment is linked to reduced quality of life, it is critical to evaluate treatments that improve the quality of life of this population or hasten recovery following treatment. 相似文献