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Objectives: To compare the effect of a soy rich diet and hormone replacement therapy (HRT) on the main biomarkers of bone turnover and bone mineral density (BMD) at postmenopausal age. Methods: 187 healthy asymptomatic postmenopausal women, aged 39–60, were recruited and randomized into a soy rich diet group, a HRT group, and a control group. Bone biomarkers and BMD were evaluated at baseline and after 6 months at the end of the study. Results: Diet is not as effective as HRT in reducing the postmenopausal turnover; however diet stimulates bone osteoblastic activity, as evidenced by significant increase in osteocalcin concentrations. BMD decreases significantly only in the control group, but not in the intervention groups. Conclusions: Our data suggest that soy products could be effective in reducing the risk of osteoporosis in asymptomatic postmenopausal women, but our findings should be confirmed before recommending the diet as a valid alternative to HRT.  相似文献   
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Interleukin‐2 (IL‐2) is a mainstay for current immunotherapeutic protocols but its usefulness in patients is reduced by severe toxicities and because IL‐2 facilitates regulatory T (Treg) cell development. IL‐21 is a type I cytokine acting as a potent T‐cell co‐mitogen but less efficient than IL‐2 in sustaining T‐cell proliferation. Using various in vitro models for T‐cell receptor (TCR)‐dependent human T‐cell proliferation, we found that IL‐21 synergized with IL‐2 to make CD4+ and CD8+ T cells attain a level of expansion that was impossible to obtain with IL‐2 alone. Synergy was mostly evident in naive CD4+ cells. IL‐2 and tumour‐released transforming growth factor‐β (TGF‐β) are the main environmental cues that cooperate in Treg cell induction in tumour patients. Interleukin‐21 hampered Treg cell expansion induced by IL‐2/TGF‐β combination in naive CD4+ cells by facilitating non‐Treg over Treg cell proliferation from the early phases of cell activation. Conversely, IL‐21 did not modulate the conversion of naive activated CD4+ cells into Treg cells in the absence of cell division. Treg cell reduction was related to persistent activation of Stat3, a negative regulator of Treg cells associated with down‐modulation of IL‐2/TGF‐β‐induced phosphorylation of Smad2/3, a positive regulator of Treg cells. In contrast to previous studies, IL‐21 was completely ineffective in counteracting the suppressive activity of Treg cells on naive and memory, CD4+ and CD8+ T cells. Present data provide proof‐of‐concept for evaluating a combinatorial approach that would reduce the IL‐2 needed to sustain T‐cell proliferation efficiently, thereby reducing toxicity and controlling a tolerizing mechanism responsible for the contraction of the T‐cell response.  相似文献   
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Infected pancreatic fluid collections: percutaneous catheter drainage   总被引:5,自引:0,他引:5  
Freeny  PC; Lewis  GP; Traverso  LW; Ryan  JA 《Radiology》1988,167(2):435-441
Thirty-eight infected pancreatic fluid collections in 23 patients with acute or chronic pancreatitis were drained percutaneously following initial diagnosis with computed tomography and fine-needle aspiration. Fifteen (65.2%) patients were cured completely without surgery. Eight (34.8%) patients required some type of surgery despite successful treatment of the fluid collection, and in two (6.5%) the collection recurred after catheter removal. Complications occurred in three (13%) patients, but only one complication (4%), empyema, was a direct result of catheter drainage. Catheter drainage time averaged 29 days for 16 patients with isolated collections and 96 days and 104 days for patients with collections with pancreatic duct fistulas (nine patients) or gastrointestinal fistulas (14 patients), respectively. This study confirms that infected pancreatic fluid collections can be safely and effectively treated with percutaneous catheter techniques in most patients.  相似文献   
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We have sequenced and compared DNA from the ends of three human chromosomes: 4p, 16p and 22q. In all cases the pro-terminal regions are subdivided by degenerate (TTAGGG)n repeats into distal and proximal sub- domains with entirely different patterns of homology to other chromosome ends. The distal regions contain numerous, short (<2 kb) segments of interrupted homology to many other human telomeric regions. The proximal regions show much longer (approximately 10-40 kb) uninterrupted homology to a few chromosome ends. A comparison of all yeast subtelomeric regions indicates that they too are subdivided by degenerate TTAGGG repeats into distal and proximal sub-domains with similarly different patterns of identity to other non-homologous chromosome ends. Sequence comparisons indicate that the distal and proximal sub-domains do not interact with each other and that they interact quite differently with the corresponding regions on other, non- homologous, chromosomes. These findings suggest that the degenerate TTAGGG repeats identify a previously unrecognized, evolutionarily conserved boundary between remarkably different subtelomeric domains.   相似文献   
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PurposeTo examine effects of race and predictors of socioeconomic status (SES) on nutrient-based diet quality and their contribution to health disparities in an urban population of low SES.DesignData were analyzed from a sample of the Healthy Aging in Neighborhoods of Diversity Across the Life Span (HANDLS) Study participants examining effects of age, sex, race, income, poverty income ratio, education, employment, and smoking status on nutrient-based diet quality as measured by a micronutrient composite index of nutrient adequacy ratios and a mean adequacy ratio. Regression models were used to examine associations and t tests were used to look at racial differences.SubjectsAfrican American and white adults ages 30 to 64 years residing in 12 predefined census tracts in Baltimore, Maryland.ResultsSex, age, education, poverty income ratio, and income were statistically significant predictors of diet quality for African Americans, while sex, education, and smoking status were statistically significant for whites. African Americans had lower mean adequacy ratio scores than whites (76.4 vs 79.1). Whites had significantly higher nutrient adequacy ratios scores for thiamin, riboflavin, folate, B12, vitamins A and E, magnesium, copper, zinc, and calcium, while African Americans had higher vitamin C scores.ConclusionEducation significantly impacted diet quality in the HANDLS sample, but race cannot be discounted. Whether the racial differences in diet quality are indicative of cultural differences in food preferences, selection, preparation, and availability, or disparities in socioeconomic status remains unclear.  相似文献   
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Progesterone administration by nasal spray   总被引:1,自引:0,他引:1  
The bioavailability and the clinical usefulness of the P administered by nasal spray were investigated. Ten healthy menopausal women received an IN spray administration (4 doses of an oleic P solution 20 mg/mL, corresponding to nearly 11.2 mg of P) and the circulating P levels were calculated. Sixty minutes after administration, the maximum concentration (CMax, 3.75 +/- 0.214 ng/mL) was reached. High P levels (greater than 2 ng/mL) lasted until 360 minutes, and the AUC 0 to 720 was 1,481.6 +/- 343 ng.h/mL. Progesterone administration by spray formulation has proven to be effective in reaching therapeutic levels and to be acceptable to patients and, probably, clinically safe.  相似文献   
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