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61.
Rohrmann S Shiels MS Lopez DS Rifai N Nelson WG Kanarek N Guallar E Menke A Joshu CE Feinleib M Sutcliffe S Platz EA 《Cancer causes & control : CCC》2011,22(8):1141-1151
Objective
Obesity is associated with a variety of chronic diseases, including cancer, which may partly be explained by its influence on sex steroid hormone concentrations. Whether different measures of obesity, i.e., body mass index (BMI), waist circumference, and percent body fat were differentially associated with circulating levels of sex steroid hormones was examined in 1,265 men, aged 20?C90+ years old, attending the morning examination session of the Third National Health and Nutrition Examination Survey (NHANES III).Materials and methods
Serum hormones were measured by immunoassay. Weight, height, and waist circumference were measured by trained staff. Percent body fat was estimated from bioelectrical impedance. Multivariate linear regression was used to estimate associations between body fatness measures and hormone levels.Results
Total and free testosterone and sex hormone binding globulin concentrations decreased, whereas total and free estradiol increased with increasing BMI, waist circumference, and percent body fat (all p trend < 0.05). The magnitude of change in these hormones was similar for a one-quartile increase in each body fatness measure.Conclusion
Measured BMI, waist circumference, and percent body fat led to similar inferences about their association with hormone levels in men. 相似文献62.
63.
[目的]了解大连市乙肝疫苗漏种的情况及其影响因素。[方法]2006年10月至2007年5月开展了大连市2002年7月1日至2006年9月3013出生儿童的乙肝疫苗查漏补种工作,对于在补种过程中新发现的漏种儿童,按照“随时发现,随时补种”的原则进行补种。[结果]本次“查漏补种”工作共摸底调查263727名儿童,查出漏种儿童2017人,漏种率为0.76%,应补种针次4198针次;实补种1933人,补种率为95.84%。大连市乙肝疫苗近5年平均接种率为99.9%,漏种率较低;流动儿童较本地常住儿童漏种率高(P〈0.05),补种率低(P〈0.05)。[结论]流动儿童中仍存在免疫空白现象。 相似文献
64.
Phosphoinositide 3-kinase is involved in the induction of the human sperm acrosome reaction downstream of tyrosine phosphorylation 总被引:7,自引:4,他引:3
Fisher HM; Brewis IA; Barratt CL; Cooke ID; Moore HD 《Molecular human reproduction》1998,4(9):849-855
In somatic cells phosphoinositide 3-kinase (PI 3-kinase) is activated upon
interaction with both receptor tyrosine kinases (RTK) and G- proteins
resulting in the production of moieties involved in the inositol
phospholipid signalling pathway. As G proteins, RTK and the inositol
phospholipids have all been implicated in the human sperm acrosome
reaction, experiments were carried out to determine whether PI 3-kinase was
also involved in this phenomenon. Wortmannin is a selective inhibitor of PI
3-kinase and was shown to significantly inhibit the acrosome reaction
induced by both mannose-bovine serum albumin (mannose-BSA) (10, 50 and 100
nM) and a polyclonal antibody raised against an extracellular region of the
sperm zona receptor kinase (ZRK, at 100 nM only). Wortmannin did not
inhibit the A23187- or progesterone-induced acrosome reaction. These
results suggest that PI 3- kinase is involved in the human sperm acrosome
reaction. The levels of tyrosine phosphorylation of sperm proteins as
detected by Western blotting using antiphosphotyrosine antibodies was not
affected by wortmannin in agonist (A23187 and mannose-BSA)-stimulated
spermatozoa. This indicated that PI 3-kinase operates downstream of
tyrosine phosphorylation in the signal transduction cascade which leads to
the human sperm acrosome reaction.
相似文献
65.
Randomised controlled trial of the impact of guidelines, prioritized review criteria and feedback on implementation of recommendations for angina and asthma.
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Richard Baker Robin C Fraser Margaret Stone Paul Lambert Keith Stevenson Chris Shiels 《The British journal of general practice》2003,53(489):284-291
BACKGROUND: Guidelines are frequently used in an attempt to influence the performance of health professionals, and a national agency has been established in England and Wales to develop and disseminate guidelines. Professionals prefer short guidelines that highlight key recommendations, but whether such guidelines are more likely to be implemented is unknown. AIM: To determine the relative impact of the dissemination of full guidelines, reduced guidelines in the form of prioritized review criteria, and review criteria supplemented by feedback. DESIGN OF STUDY: Cluster randomised controlled trial, with an incomplete block design. SETTING: Eighty-one general practices in Leicestershire, Lincolnshire, Northamptonshire, North Derbyshire, and Nottinghamshire. METHOD: The practices received one of the study interventions, either for care of adults with asthma or for care of people with angina. Data were collected before and after the interventions, the process measures being adherence to ten recommendations about asthma and 14 about angina, and outcome measures being scores in response to an asthma symptom questionnaire or the Seattle Angina Questionnaire, and levels of patient satisfaction. RESULTS: There were no consistent differences between the interventions in stimulating improvements in performance as indicated by adherence to the recommendations for asthma or angina. Patients with angina in practices that had received criteria or criteria plus feedback reported better symptom control. CONCLUSION: The dissemination of guidelines in the format of prioritized review criteria does not increase adherence to recommendations in comparison with the traditional guideline format, and the further provision of feedback has minimal additional effect. 相似文献
66.
Air enema for diagnosis and reduction of intussusception: clinical experience and pressure correlates 总被引:3,自引:0,他引:3
Air enema was used for exclusion, diagnosis, initial movement, and complete reduction of intussusception in 186 pediatric patients. Average pressure needed for initial movement of intussusception was 56.5 mm Hg; average maximum pressure of 97.8 mm Hg was required for complete reduction. Average fluoroscopy time required for intussusception reduction was 94.8 seconds; an average of 41.8 seconds was required to exclude intussusception. Intussusception was diagnosed in 75 patients, and reduction was accomplished in 65 (87%). Of 100 consecutive patients that underwent hydrostatic reduction of intussusception at the authors' institution, reduction was successful in 55. Compared with hydrostatic enema, air enema involves shorter fluoroscopy time and lower radiation dose to the patient. Air enema is safe and effective for diagnosis and treatment of intussusception in infants and children and has replaced hydrostatic enema for such procedures at the authors' institution. 相似文献
67.
The effect of salt on blood pressure (BP) is controversial. A more important question is whether salt can produce cardiac target-organ damage, irrespective of its effect on BP. We assessed the effect of salt with fludrocortisone on QT dispersion and echocardiographic left ventricular diastolic function in a prospective interventional study involving 29 hypertensive subjects with a raised aldosterone/renin ratio who were hospitalized for investigation of possible primary aldosteronism. Each subject over 4 days was given a total of 28.8 g (480 mmol) of sodium chloride and 1.5 mg of fludrocortisone with potassium supplementation. Baseline and posttreatment 12-lead ECGs and echocardiograms were obtained. There were no significant changes in body weight, pulse rate, or BP after treatment with salt and fludrocortisone. Plasma sodium was significantly increased from 141.4 (SD 2.1) to 142.6 (SD 2.4) mmol/L (P:=0.001). QT and QTc dispersion both significantly increased: +19.6 (SD 16.5) ms (95% CI, 13.4 to 25.9) (P:<0.001) and +19.8 (SD 20.9) ms (95% CI, 11.8 to 27.7) (P:<0.001), respectively. There were no significant changes in (n=15) left ventricular dimensions or systolic function, but all diastolic filling indexes, including the preload-independent index, flow propagation velocity (55.49 [SD 10.91] to 48.96 [SD 11.40] cm/s, P:=0.018) worsened, suggesting significant deterioration of left ventricular diastolic function with salt and fludrocortisone. In conclusion, a combination of salt with fludrocortisone increased QT dispersion and impaired left ventricular diastolic relaxation in hypertensive patients with high aldosterone/renin ratios. This raises the possibility that salt may have BP-independent adverse cardiac effects in susceptible hypertensive subjects. 相似文献
68.
69.
Frequency and significance of concurrent hepatitis B surface antigen and antibody in acute and chronic hepatitis B 总被引:3,自引:0,他引:3
Of 228 consecutive hepatitis B surface antigen (HBsAg)-positive patients who had simultaneous hepatitis B surface antibody (anti-HBs) determinations, HBsAg and anti-HBs were found concurrently in 73 (32%). Concurrence was found with greater frequency in patients with chronic active hepatitis than in those with acute hepatitis (36/57 vs 13/38, p less than 0.02). Patients with chronic active hepatitis had concurrent markers more commonly than those with chronic persistent hepatitis or asymptomatic carrier state (36/57 vs. 24/133, p less than 0.001). No major risk factors were identified. Hepatitis B e antigen was detected more frequently in patients with concurrence (68% vs. 42%, p less than 0.01). Subtyping was possible in 30 patients with chronic infection, including 18 with chronic active hepatitis, 7 with chronic persistent hepatitis, and 5 with a carrier state. In 25 patients, HBsAg subtype ad was found with antibody to subdeterminant y and in four instances, HBsAg subtype ay was found with antibody to subdeterminant d. Only 1 patient had homotypic HBsAg and anti-HBs. Of 38 patients who had successive determinations, concurrence was constant in 29. In 9 others, anti-HBs was detected intermittently and the heterotypia of the recurrent antibody remained constant. Antibody to hepatitis delta-virus was not detected. We conclude that concurrent HBsAg and anti-HBs are found frequently in acute and chronic hepatitis B. The markers are commonly heterotypic in chronic disease. The presence of heterotypic markers is not associated with specific risk factors or delta-infection. Concurrence is associated with evidence of viral replication and features of active inflammation. 相似文献
70.
The binding of the cardiac glycoside, ouabain, to cells had been used to quantify the number of active cation pumps. In this study, lymphocytes were incubated with 3H-ouabain and the equilibrium binding analyzed for the maximal number of specific binding sites. Lymphocytes from normal peripheral blood bound 44,200 +/- 9920 molecules/cell, compared with 29,200 +/- 8370 molecules/cell for the lymphocytes of chronic lymphocytic leukemia (CLL) subjects. This difference was significant (p less than 0.01) and did not reflect a lower number of sites on B cells than T cells, since B-cell-enriched lymphocytes from normal peripheral blood showed the same ouabain binding characteristics as the standard T-cell-rich preparation. Although monocytes bind threefold more ouabain than lymphocytes, the small monocyte contamination (3.0%) in normal lymphocyte preparations could not account for the difference between normal and CLL. The fewer ouabain binding sites on CLL lymphocytes may reflect both their smaller size (by 10%) and lower mitotic activity compared with lymphocytes from normal peripheral blood. 相似文献