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91.
92.
Hsia J Wu L Allen C Oberman A Lawson WE Torréns J Safford M Limacher MC Howard BV;Women's Health Initiative Research Group 《American journal of preventive medicine》2005,28(1):19-25
BACKGROUND: To evaluate the hypothesis that physical activity independently predicts type 2 diabetes risk in postmenopausal African-American, Hispanic, Asian, and Caucasian women. METHODS: We prospectively evaluated the relationship between incident type 2 diabetes, walking, and total physical activity at baseline in the Women's Health Initiative Observational Study. Baseline data were collected between September 1994 and December 1998; incident diabetes was identified through August 2002. Hazard ratios for self-reported diabetes adjusted for body mass index (BMI) and other variables were evaluated across categories of physical activity in Caucasian, African-American, Hispanic, and Asian/Pacific Islander women. RESULTS: Incident diabetes was reported by 2.2% of Caucasian, 6.2% of African-American, 4.5% of Hispanic, 3% of Asian, and 5.7% of American Indian women (p <0.0001 across ethnic groups) during 458,018 woman-years of follow-up. Among Caucasian women, walking (multivariate-adjusted hazard ratios 1.00, 0.85, 0.87, 0.75, 0.74; p <0.001 for trend across exercise quintiles) and total physical activity score (hazard ratios 1.00, 0.88, 0.74, 0.80, 0.67; p =0.002) demonstrated a strong inverse relationship with diabetes risk. In BMI-adjusted models, African-American women in higher physical activity categories were less likely to develop diabetes than women in the lowest physical activity category. After adjusting for age and multiple risk factors, however, no significant association between physical activity and diabetes risk was apparent for African-American, Hispanic, or Asian women. CONCLUSIONS: These findings suggest a stronger and more independent association of physical inactivity with development of diabetes in Caucasian women than in minority women, but could also be explained by less precise risk estimates in minority women or the role of chance. 相似文献
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Streptococcal toxic shock syndrome in children without skin and soft tissue infection: report of four cases 总被引:2,自引:0,他引:2
Streptococcal toxic shock syndrome is a fulminant, highly fatal disease characterized by evidence of group A beta-haemolytic streptococcus infection and early shock with consecutive organ failure. In adults, affected individuals usually have preceding skin or soft tissue infection. However, in paediatric patients, except for varicella, the background focus is usually respiratory tract infection, and early diagnosis of streptococcal toxic shock syndrome in such patients is difficult. We report four previously healthy children with streptococcal toxic shock syndrome. Pharyngitis was identified in three cases. All of them had constitutional symptoms such as fever, vomiting, diarrhoea, abdominal pain and physical findings of tachycardia and diffuse abdominal tenderness, but no concomitant skin infection. CONCLUSION: Streptococcal toxic shock syndrome should be considered in paediatric patients with fever, vomiting, diarrhoea, abdominal pain and early shock. Early diagnosis, prompt initiation of antibiotics and aggressive fluid therapy are lifesaving for such patients. 相似文献
96.
Effects of conjugated equine estrogen in postmenopausal women with hysterectomy: the Women's Health Initiative randomized controlled trial 总被引:55,自引:12,他引:43
Anderson GL Limacher M Assaf AR Bassford T Beresford SA Black H Bonds D Brunner R Brzyski R Caan B Chlebowski R Curb D Gass M Hays J Heiss G Hendrix S Howard BV Hsia J Hubbell A Jackson R Johnson KC Judd H Kotchen JM Kuller L LaCroix AZ Lane D Langer RD Lasser N Lewis CE Manson J Margolis K Ockene J O'Sullivan MJ Phillips L Prentice RL Ritenbaugh C Robbins J Rossouw JE Sarto G Stefanick ML Van Horn L Wactawski-Wende J Wallace R Wassertheil-Smoller S;Women's Health Initiative Steering Committee 《JAMA》2004,291(14):1701-1712
Context Despite decades of use and considerable research, the role of estrogen alone in preventing chronic diseases in postmenopausal women remains uncertain. Objective To assess the effects on major disease incidence rates of the most commonly used postmenopausal hormone therapy in the United States. Design, Setting, and Participants A randomized, double-blind, placebo-controlled disease prevention trial (the estrogen-alone component of the Women's Health Initiative [WHI]) conducted in 40 US clinical centers beginning in 1993. Enrolled were 10 739 postmenopausal women, aged 50-79 years, with prior hysterectomy, including 23% of minority race/ethnicity. Intervention Women were randomly assigned to receive either 0.625 mg/d of conjugated equine estrogen (CEE) or placebo. Main Outcome Measures The primary outcome was coronary heart disease (CHD) incidence (nonfatal myocardial infarction or CHD death). Invasive breast cancer incidence was the primary safety outcome. A global index of risks and benefits, including these primary outcomes plus stroke, pulmonary embolism (PE), colorectal cancer, hip fracture, and deaths from other causes, was used for summarizing overall effects. Results In February 2004, after reviewing data through November 30, 2003, the National Institutes of Health (NIH) decided to end the intervention phase of the trial early. Estimated hazard ratios (HRs) (95% confidence intervals [CIs]) for CEE vs placebo for the major clinical outcomes available through February 29, 2004 (average follow-up 6.8 years), were: CHD, 0.91 (0.75-1.12) with 376 cases; breast cancer, 0.77 (0.59-1.01) with 218 cases; stroke, 1.39 (1.10-1.77) with 276 cases; PE, 1.34 (0.87-2.06) with 85 cases; colorectal cancer, 1.08 (0.75-1.55) with 119 cases; and hip fracture, 0.61 (0.41-0.91) with 102 cases. Corresponding results for composite outcomes were: total cardiovascular disease, 1.12 (1.01-1.24); total cancer, 0.93 (0.81-1.07); total fractures, 0.70 (0.63-0.79); total mortality, 1.04 (0.88-1.22), and the global index, 1.01 (0.91-1.12). For the outcomes significantly affected by CEE, there was an absolute excess risk of 12 additional strokes per 10 000 person-years and an absolute risk reduction of 6 fewer hip fractures per 10 000 person-years. The estimated excess risk for all monitored events in the global index was a nonsignificant 2 events per 10 000 person-years. Conclusions The use of CEE increases the risk of stroke, decreases the risk of hip fracture, and does not affect CHD incidence in postmenopausal women with prior hysterectomy over an average of 6.8 years. A possible reduction in breast cancer risk requires further investigation. The burden of incident disease events was equivalent in the CEE and placebo groups, indicating no overall benefit. Thus, CEE should not be recommended for chronic disease prevention in postmenopausal women. 相似文献
97.
Transmission and clinical features of enterovirus 71 infections in household contacts in Taiwan 总被引:6,自引:0,他引:6
Chang LY Tsao KC Hsia SH Shih SR Huang CG Chan WK Hsu KH Fang TY Huang YC Lin TY 《JAMA》2004,291(2):222-227
Context Although enterovirus 71 has caused epidemics associated with significant morbidity and mortality, its transmission has not been thoroughly investigated. Objectives To investigate enterovirus 71 transmission and determine clinical outcomes within households. Design, Setting, and Participants Prospective family cohort study to investigate patients at a children's hospital in Taiwan and family members of these patients who had signs and symptoms suggestive of enterovirus 71 between February 2001 and August 2002. Patients and household members underwent clinical evaluations, virological studies, questionnaire-based interviews, and were followed up for 6 months. Main Outcome Measures Enterovirus 71 infection, defined as a positive viral culture from a throat or rectal swab, or the presence of IgM or a 4-fold increase in neutralizing antibody in serum; and clinical syndromes, defined as asymptomatic; uncomplicated symptomatic; and complicated; with unfavorable outcomes of sequelae or death. Results Ninety-four families (433 family members) had at least 1 family member with evidence of enterovirus 71 infection. The overall enterovirus 71 transmission rate to household contacts was 52% (176/339 household contacts). Transmission rates were 84% for siblings (70/83); 83%, cousins (19/23); 41%, parents (72/175); 28%, grandparents (10/36); and 26%, uncles and aunts (5/19). Of 183 infected children, 11 (6%) were asymptomatic and 133 (73%) had uncomplicated illnesses (hand, foot, and mouth disease, herpangina, nonspecific febrile illness, upper respiratory tract infection, enteritis, or viral exanthema). Twenty-one percent (39/183) experienced complicated syndromes including the central nervous system or cardiopulmonary failure. During the 6-month follow-up, 10 died and 13 had long-term sequelae consisting of dysfunction in swallowing, cranial nerve palsies, central hypoventilation, or limb weakness and atrophy. Age younger than 3 years was the most significant factor associated with an unfavorable outcome in children (P = .004). Among 87 infected adults, 46 (53%) were asymptomatic, 34 (39%) had nonspecific illnesses of fever, sore throat, or gastrointestinal discomfort, and 7 (8%) had hand, foot, and mouth disease. There were no complicated cases in adults. Conclusions Enterovirus 71 household transmission rates were high for children in Taiwan and severe disease with serious complications, sequelae, and death occurred frequently. In contrast, adults had a much lower rate of acquisition of the infection and much less adverse sequelae. 相似文献
98.
Yu YH Hsu WH Hsu NY Lin TY Hsia TC Sun SS Kao CH 《Japanese journal of clinical oncology》2004,34(8):445-451
BACKGROUND: This study examines the usefulness of thallium-201 single photon emission computed tomography ((201)Tl SPECT) in differentiating pulmonary malignancies from benign lesions by using dual phase (201)Tl scintigraphy. METHODS: One hundred and six patients with thoracic lesions and confirmed diagnoses were assessed by (201)Tl chest SPECT examinations; of these 106 enrolled thoracic lesions, 59 were malignancies and 47 were benign lesions. Dual phase (201)Tl SPECT was performed with an early image acquired at 10-20 min and a delayed image at 2-3 h after intravenous injection of 2-3 mCi of (201)Tl. The results of (201)Tl SPECT images were classified as either malignant or benign lesions by visual interpretation: the lesion was interpreted as positive for malignancy if the uptake of (201)Tl in the lung lesion in the delayed phase was increased or persistent as compared with that in the early phase image; otherwise, it was considered as a benign lesion. Simultaneously, the traditional method of retention index (RI) was also calculated to help in the differential diagnosis of pulmonary lesions. Then, both methods of dual phase (201)Tl SPECT, visual reading and traditional RI, were compared to differentiate pulmonary malignancies from benign lesions. RESULTS: Analyzing the image results, we found that dual phase (201)Tl SPECT could differentiate pulmonary malignancies from benign lesions with a sensitivity of 83%, a specificity of 91% and an accuracy of 87%. Moreover, by using the traditional RI method of (201)Tl SPECT, it could differentiate pulmonary malignancy from benign lesions with a sensitivity of 79.3%, a specificity of 80.8% and an accuracy of 80%. CONCLUSIONS: We conclude that using dual phase (201)Tl SPECT with visual interpretation is a simpler and potentially more effective method for differentiating pulmonary malignancies from benign lesions, with results compatible with the traditional RI method of (201)Tl SPECT. 相似文献
99.
Association of ocular dominance and anisometropic myopia 总被引:7,自引:0,他引:7
Cheng CY Yen MY Lin HY Hsia WW Hsu WM 《Investigative ophthalmology & visual science》2004,45(8):2856-2860
PURPOSE: To determine the association between ocular dominance and degree of myopia in patients with anisometropia. METHODS: Fifty-five subjects with anisometropic myopia were recruited. None of them had amblyopia. Refractive error and axial length were measured in each subject. Ocular dominance was determined using the hole-in-the-card test and convergence near-point test. RESULTS: There was a threshold level of anisometropia (1.75 D) beyond which the dominant eye was always more myopic than the nondominant eye. Of the 33 subjects with anisometropia of < or =1.75 D, the dominant eye was more myopic in 17 (51.5%) subjects. Dominant eyes, determined by the hole-in-the-card test, had a significantly greater myopic spherical equivalent (-5.27 +/- 2.45 D) than nondominant eyes (-3.94 +/- 3.10 D; P < 0.001). Dominant eyes also had a longer axial length than nondominant eyes (25.15 +/- 0.96 mm vs. 24.69 +/- 1.17 mm, respectively; P < 0.001). The difference was more evident in those subjects with higher anisometropia (>1.75 D), but was not significant in those with lower anisometropia (< or =1.75 D). Similar results were obtained using the convergence near-point test. CONCLUSIONS: The present study shows that the dominant eye has a greater degree of myopia than the nondominant eye in subjects with anisometropic myopia. Taking ocular dominance into account in the design of randomized clinical trails to assess the efficacy of myopia interventions may provide useful information. 相似文献
100.
This is the first report that a Fusarium toxin nivalenol (NIV) naturally existing at high levels in dietary food in high-risk areas of cancer of esophagus and gastric cardia in China induced benign and malignant tumors in mice. The levels of two Fusarium toxins, nivalenol and deoxynivalenol (DON) were quantitated using high performance liquid chromatography (HPLC) in a total of 97 samples of dietary wheat flour, barley and corn collected from families in two areas with high mortality rate of cancer of esophagus and gastric cardia (132/100,000), Linxian, Henan province and Cixiang, Hepei province, China. The mean level of NIV and DON in three dietary foods was 830+/-927 microg/kg (range 584-1,780 microg/kg) and 4,281+/-6,114 microg/kg (range 732-10,980 microg/kg) respectively. The highest mean level of NIV was 1,780+/-1,705 microg/kg found in barley from Linxian, that of DON was 10,980+/-10,139 microg/kg found in corn from Cixiang. NIV was undetectable in 2 samples of rice from USA. The mean levels of NIV in three main dietary foods in those two high-risk areas were estimated at 400 to 800-fold higher than that in the USA, where NIV was undetectable in dietary food, and the mortality rate of esophageal cancer is <5/100,000 in white Caucasians in the USA, (odds ratio was estimated at 17-34, p<0.000005). These data suggest that Linxian and Cixiang peasants who consumed a diet with high NIV had significantly higher risk for developing esophageal cancer than the US residents who consumed food without or with negligible amounts of NIV. Three repeated experiments were performed using Balb/C mice with inter-mittent application of NIV, alternate with 12-Tetradeconoyl-phorbol-13-acetate (TPA) application on skin. Papillomas and carcinomas developed in a total of 23/49 (47%) mice that survived 11-60 weeks of experiments. Among all the tumors, 4 carcinomas in 3 mice were identified. No tumors were found in the 60 control mice applying either TPA or acetone (solvent) only on skin. 相似文献