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We examined androgen responses in hyperandrogenic (polycystic ovarian disease [PCOD]) and normal women after an acute endogenous insulin elevation. Standard intravenous glucose tolerance tests (IVGTTs), modified to include a tolbutamide injection 20 minutes after IVGTTs, were performed. Polycystic ovarian disease patients were studied in the untreated state, after 6 weeks of ovarian androgen suppression with leuprolide acetate, after a 6-week rest period, and after 6 weeks of antiandrogen therapy with spironolactone. Normal menstruating women were studied during the early follicular, midcycle, and luteal phases of a single cycle. An acute rise in insulin did not alter serum testosterone or androstenedione levels in PCOD or normal women. A significant rise in dehydroepiandrosterone sulfate after modified IVGTTs was found in both hyperandrogenic and normal cycling women. Although these results are not supportive of the theory that insulin acts on the ovary to stimulate androgen production, they may be because of the short time course of insulin elevation that occurs during an IVGTT.  相似文献   
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Summary High resolution spectral methods are explored as an alternative to broad band spectral parameters (BBSP) in quantitative EEG analysis. In a previous paper (Valdes et al. 1990b) regression equations (Developmental surfaces) were introduced to characterize the age-frequency distribution of the mean and standard deviation of the log spectral EEG power in a normative sample. These normative surfaces allow the calculation of z transformed spectra for all derivations of the 10/20 system and z maps for each frequency. Clinical material is presented that illustrates how these procedures may pinpoint frequencies of abnormal brain activity and their topographic distribution, avoiding the frequency and spatial smearing that may occur using BBSP. The increased diagnostic accuracy of high resolution spectral methods is demonstrated by means of receiver operator characteristic (ROC) curve analysis. Procedures are introduced to avoid type I error inflation due to the use of more variables in this type of procedure.  相似文献   
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Summary Telomere length decreases with age and is associated with osteoblast senescence. In 2,150 unselected women, leukocyte telomere length was significantly correlated with bone mineral density. Clinical osteoporosis was associated with shorter telomeres, suggesting that telomere length can be used as a marker of bone aging. Introduction The length of telomeres in proliferative cells diminishes with age. Telomere shortening and telomerase activity have been linked to in vitro osteoblast senescence and to increased secretion of pro-inflammatory cytokines. We explored whether bone mineral density correlates with telomere length in leukocytes. Materials and methods The relationship between leukocyte telomere length, bone mineral density (BMD) and osteoporosis (as defined by the World Health Organization) was examined in a cohort of 2,150 women from a population-based twin cohort aged 18–79. Results After adjusting for age, body mass index, menopausal status, smoking, hormone replacement therapy status, telomere length was positively correlated with BMD of the spine (p < 0.005), forearm (p < 0.013), but not the femoral neck (p < 0.06). Longer telomeres were associated with reduced the risk of clinical OP at two or more sites (odds ratio = 0.594 95% CI 0.42–0.84 p < 0.003) and in women over the age of 50, clinical osteoporosis was associated with 117 bp shorter telomere length (p < 0.02) equivalent to 5.2 years of telomeric aging. Conclusions Shortened leukocyte telomere length is independently associated with a decrease in BMD and the presence of osteoporosis in women. Our data provide evidence that leukocyte telomere length could be a marker of biological aging of bone.  相似文献   
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Background Breast carcinoma is the most frequently diagnosed malignancy in women of the North America. The combination of breast-conservation surgery and radiotherapy has become a standard of treatment for most breast cancers. It is critical to obtain clear margins to minimize local recurrence. The literature suggests that intraoperative touch preparation cytology (IOTPC) can be useful in evaluation of margins. Invasive lobular carcinoma (ILC) accounts for 10% to 15% of all breast cancers. Obtaining clear margins in ILC can be more challenging. Literature shows the positive margin rate for ILC to be as high as 60%. This report describes our experience with IOTPC for margin assessment in ILC by a single surgeon at Beth Israel Medical Center. The purpose of this study is to determine whether IOTPC is reliable for ILC. Methods A prospective review of 73 patients who underwent breast-conservation surgery with the use of IOTPC for margin assessment at Beth Israel Medical Center was performed. Pathology revealed ILC in 12 of these patients (16.4%), who are the subjects of this study. The lumpectomy specimens were oriented by the surgeon intraoperatively and were submitted fresh to pathology for cytologic assessment. IOTPC consisted of touching the corresponding margin onto the glass slide. The principle of this technique is that if cancer cells are present, they will stick to the slide, whereas fat cells will not. Six slides were prepared for each lumpectomy specimen. Air-dried samples were stained immediately by the Diff-Quik method and examined under the microscope by a cytopathologist. Results Twelve patients with ILC underwent breast-conservation surgery with IOTPC for assessment of 72 margins. Ten patients had lobular carcinoma only, and the remaining two patients had a combination of lobular and ductal carcinoma. There was a correlation between IOTPC and final pathology in 60 of 72 margins, which accounted for 83.3% of the cases. IOTPC for assessment of margins in patients undergoing breast-conservation surgery for ILC has a sensitivity of 8.3%, specificity of 98.3%, positive predictive value of 50%, and negative predictive value of 84.3%. Conclusions On the basis of our experience, IOTPC is of limited value for intraoperative assessment of margins for ILC. Poster presentation at the Sixth Annual Meeting of the American Society of Breast Surgeons, March 16–20, 2005, Los Angeles, California.  相似文献   
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The wound environment is a fertile ground for biofilm forming pathogens. Once biofilms form within the wound, they can be very challenging to eradicate. The purpose of this study was to examine the effect of a gelling fiber dressing with silver using a well‐established porcine wound biofilm model. Deep partial thickness wounds were inoculated with Pseudomonas aeruginosa ATCC 27312 and covered with a polyurethane film dressing to promote biofilm formation. Wounds were then divided into treatment groups: gelling fiber dressing with silver, gelling fiber dressing without silver, hydrofiber dressing with silver, benzethonium chloride and ethylenediaminetetraacetic acid and compared to untreated control. Microbiological, biofilm, and histological wound assessments were performed on days 3, 5, and 7 postinfection. Treatment with gelling fiber dressing with silver resulted in significant reduction of P. aeruginosa biofilm when compared to all other treatment groups on every assessment time point. In addition, gelling fiber dressing with silver treatment resulted in detachment of biofilm from the wound, while wounds treated with gelling fiber dressing with and without silver showed more granulation tissue formation on day 3. Our data show that a new gelling fiber dressing with silver was effective in reducing biofilm associated P. aeruginosa in vivo. This study may have important clinical implications especially for wounds heavily colonized with gram‐negative biofilm‐forming bacteria.  相似文献   
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