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111.
Early life sexual factors, including histories of sexually transmitted infections, young-onset prostatitis, and frequency of ejaculation, were investigated in relation to lower urinary tract symptoms (LUTS) in a large case-control study nested within the Health Professionals Follow-up Study. In 1992, study participants were asked to provide information on their histories of sexually transmitted infections, prostatitis, ejaculation frequency, surgery for an enlarged prostate, and LUTS. Information on prostate surgery and LUTS was updated every 2 years. LUTS cases were defined as men who reported surgery for an enlarged prostate or high-moderate to severe LUTS (> or = 15 points on the American Urological Association symptom index) on any study questionnaires (n = 4,608). Controls were men who did not report surgery for an enlarged prostate and who scored 0-7 points on the American Urological Association symptom index on all questionnaires (n = 17,967). History of gonorrhea (adjusted odds ratio = 1.76, 95% confidence interval: 1.43, 2.15) or young-onset prostatitis (adjusted OR = 1.55, 95% confidence interval: 1.22, 1.96) was positively associated with LUTS. No association was observed between ejaculation frequency in early adulthood and LUTS. These results suggest that early genitourinary infections may contribute to later development of LUTS, although confirmation in additional population settings is warranted.  相似文献   
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OBJECTIVE: Coffee consumption is associated with reduced risk of type 2 diabetes, but the mechanism is not clearly understood. Elevated C-peptide, as a marker of insulin secretion, has been linked to insulin-resistant type 2 diabetes. In this study, we examined consumption of caffeinated and decaffeinated coffee and total caffeine in relation to concentrations of plasma C-peptide. RESEARCH DESIGN AND METHODS: Plasma C-peptide concentrations were measured in a cross-sectional setting among 2,112 healthy women from the Nurses' Health Study I who provided blood samples in 1989-1990. Consumption of caffeinated and decaffeinated coffee and total caffeine was assessed using a semiquantitative food-frequency questionnaire in 1990. RESULTS: Intakes of caffeinated and decaffeinated coffee and caffeine in 1990 were each inversely associated with C-peptide concentration in age-adjusted, BMI-adjusted, and multivariable-adjusted analyses. In multivariable analysis, concentrations of C-peptide were 16% less in women who drank >4 cups/day of caffeinated or decaffeinated coffee compared with nondrinkers (P < 0.005 for each). Women in the highest quintile compared with the lowest quintile of caffeine intake had 10% lower C-peptide levels (P = 0.02). We did not find any association between tea and C-peptide. The inverse association between caffeinated coffee and C-peptide was considerably stronger in obese (27% reduction) and overweight women (20% reduction) than in normal weight women (11% reduction) (P = 0.005). CONCLUSIONS: Our findings suggest a potential reduction of insulin secretion by coffee in women. This reduction may be related to other components in coffee rather than caffeine.  相似文献   
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Summary: The effects of monomer/starch feed ratios and moisture content during reactive extrusion of starch‐polyacrylamide graft copolymers were investigated. Acrylamide/starch ratios ranged from 0.20 to 1.87 at 50% moisture content, while moisture content was increased from 45 to 75% with an acrylamide/starch ratio of 0.33. Average conversion was 86.6% (±3.5%), independent of monomer content, at acrylamide/starch ratios of 0.77 and less. Conversion increased to approximately 95% when the acrylamide/starch ratio exceeded unity. Molecular weight of grafted polyacrylamide increased as the acrylamide/starch ratio increased. Graft efficiency was constant at approximately 75% for monomer/starch ratios of 0.77 or less, and decreased to 52.3% as the monomer/starch ratio increased to 1.87. Higher acrylamide/starch ratios gave more frequent grafts of higher molecular weight. As moisture content decreased from 75 to 45%, conversion and graft content increased from 78 and 14% to 97 and 23%, respectively. Lower moisture content gave fewer grafts of higher molecular weight. Ungrafted polyacrylamide homopolymer increased with monomer/starch ratio and moisture content. These results indicate that graft copolymer properties can be controlled through the monomer/starch ratio and moisture content during reactive extrusion.

Molecular weight distributions of grafted polyacrylamide at different moisture contents during extrusion: A) 75%; B) 65%; C) 55%; D) 45%.  相似文献   

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In the event of unexpectedly finding an ovarian cyst at the time of laparoscopy, serum CA 125 assay is helpful in deciding the subsequent management of the cyst. It is unclear, however, when the CA 125 should be checked. There has been some debate as to the effect of laparoscopy on the level of CA 125 and whilst it is widely accepted that laparotomy will increase the level of CA 125 the effects of laparoscopy have not been investigated until now. Pre and post operative CA 125 levels were measured in 20 patients undergoing simple laparoscopic surgery. Analysis of the results indicate that simple laparoscopic procedures have an insignificant effect on serum CA 125 levels checked in the immediate post operative period.  相似文献   
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Bloomer R  Willett K  Pallister I 《Injury》2004,35(5):490-493
The stove-in chest is a rare form of flail chest in which there is collapse of a segment of the chest wall, associated with a high immediate mortality. A 65-year-old male pedestrian was admitted with severe chest pain and dyspnoea, after being struck by a car. The initial chest radiograph demonstrated multiple right-sided rib fractures and pulmonary contusion. His gas exchange was good, and after pain relief via an epidural catheter was achieved, an intercostal drain was inserted into the right hemi-thorax. Clinically apparent deformation of the chest then occurred. A further chest radiograph confirmed the stove-in chest. The patient remained well initially, but on day 5 he deteriorated precipitously with respiratory failure, and signs of systemic sepsis. He died despite maximal ventilatory and inotropic support on the Intensive Care Unit (ICU). Post-mortem examination demonstrated congested, oedematous lungs with a right-sided empyema. The management of complex flail chest injuries requires treatment to be tailored to the individual patient. Early ventilatory support, despite good gas exchange, may have closed down the pleural space prevented the empyema. Prophylactic ventilation and possibly surgical stabilisation of the chest wall should be considered early in the course of admission, even when the conventional parameters to indicate ventilation are not met.  相似文献   
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