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601.
OBJECTIVE: There are few data to guide the choice between colonoscopy and flexible sigmoidoscopy in patients with nonacute rectal bleeding, especially in younger age groups. Our aim was to determine the yield of colonoscopy for significant proximal large bowel disease in the absence of significant distal disease, with special reference to young patients. METHODS: This was a retrospective study of data collected prospectively in 1766 patients (median age 57 yr, 711 women). The endoscopic database (GI-Trac) contained 152 discrete fields for data input. Multiple logistic regression analysis was performed to identify variables independently associated with the presence of isolated significant proximal disease. RESULTS: Young patients had a higher percentage of normal examinations than did older patients. The incidence of diverticular disease, small polyps, large polyps, and cancer rose with increasing age. No patient aged <40 yr had an isolated proximal cancer, but 7% had other significant isolated proximal disease. There was no overall association between age and significant proximal disease in the absence of significant distal disease (p = 0.66). The only variable associated with isolated proximal disease was anemia (odds ratio = 1.81; 95% CI = 1.11-2.93; p = 0.02). CONCLUSION: The yield of colonoscopy (beyond the range of sigmoidoscopy) for neoplasia is low in patients aged <40 yr, but other significant disease may be missed if age is the only criterion determining colonoscopy use.  相似文献   
602.
OBJECTIVE: To determine reference values for fat-free mass index (FFMI) and fat mass index (FMI) in a large Caucasian group of apparently healthy subjects, as a function of age and gender and to develop percentile distribution for these two parameters. DESIGN: Cross-sectional study in which bioelectrical impedance analysis (50 kHz) was measured (using tetrapolar electrodes and cross-validated formulae by dual-energy X-ray absorptiometry in order to calculate FFMI (fat-free mass/height squared) and FMI (fat mass/height squared). SUBJECTS: A total of 5635 apparently healthy adults from a mixed non-randomly selected Caucasian population in Switzerland (2986 men and 2649 women), varying in age from 24 to 98 y. RESULTS: The median FFMI (18-34 y) were 18.9 kg/m(2) in young males and 15.4 kg/m(2) in young females. No difference with age in males and a modest increase in females were observed. The median FMI was 4.0 kg/m(2) in males and 5.5 kg/m(2) in females. From young to elderly age categories, FMI progressively rose by an average of 55% in males and 62% in females, compared to an increase in body mass index (BMI) of 9 and 19% respectively. CONCLUSIONS: Reference intervals for FFMI and FMI could be of practical value for the clinical evaluation of a deficit in fat-free mass with or without excess fat mass (sarcopenic obesity) for a given age category, complementing the classical concept of body mass index (BMI) in a more qualitative manner. In contrast to BMI, similar reference ranges seems to be utilizable for FFMI with advancing age, in particular in men.  相似文献   
603.
604.
The magnitude of variability in resting energy expenditure (REE) during the day was assessed in nine healthy young subjects under two nutritional conditions: 1) mixed nutrient (53% carbohydrate, 30% fat, 17% protein) enteral feeding at an energy level corresponding to 1.44 REE; and 2) enteral fasting, with only water allowed. In each subject, six 30-min measurements of REE were performed using indirect calorimetry (hood system) at 90-min intervals from 9 AM to 5 PM. The mean REE and respiratory quotient were significantly (p less than .01) greater during feeding than during fasting (1.08 +/- 0.07 [SEM] vs. 1.00 +/- 0.06 kcal/min and 0.874 +/- 0.007 vs. 0.829 +/- 0.008 kcal/min, respectively). Mean postprandial thermogenesis was 4.9 +/- 0.4% of metabolizable energy administered. The intraindividual variability of REE throughout the day, expressed as the coefficient of variation, ranged from 0.7% to 2.0% in the fasting condition and from 1.2% to 4.1% in the feeding condition. There was no significant difference between the REE measured in the morning and that determined in the afternoon.  相似文献   
605.
606.
高密度脂蛋白胆固醇的检测方法及标准化研究进展鄢盛恺林其燧众多流行病学研究证实,高密度脂蛋白胆固醇(HDL-C)水平与动脉粥样硬化(AS)呈负相关。美国Framingham的研究显示,HDL-C每减少0.026mmol/L(1mg/dl),冠心病(CH...  相似文献   
607.
011 PCI应用药物洗脱支架与CABG术后生活质量改善的比较[Cohen DJ,van Hout B,Serruys PW,et al.N Engl J Med,2011,364(11):1016-1026(英文)]经皮冠状动脉介入治疗(PCI)和冠状动脉旁路移植术(CABG)都可选择用于治疗多支血管冠状动脉病变;以往研究显示:多支血管冠状动脉病变实施CABG或PCI实施气囊血管成形术或金属裸支架后,心绞痛发作频率和生活质量均明显改  相似文献   
608.
The ability of particles with a 50% cut-off aerodynamic diameter of 10 microm (PM10) to cause respiratory health effects possibly depends on their composition. This study evaluated whether the soluble elemental concentrations in PM10 were related to acute respiratory health effects. The Pollution Effects on Asthmatic Children in Europe (PEACE) study is a multicentre study of the acute effects of PM10 and other air pollution components on the respiratory health of children with chronic respiratory symptoms in urban and suburban panels. Children, 1208, divided among 17 panels were followed for > or =2 months. Exposure to air pollution was monitored on a daily basis. Health status was monitored by twice daily peak expiratory flow (PEF) measurements and a symptom diary. Median concentrations of iron ranged 105-1,110 ng x m(-3) in the urban and 32-517 ng x m(-3) in the suburban locations. The daily concentrations of most elements were not associated with daily variation in PEF, prevalence of respiratory symptoms or bronchodilator use. Silicon and iron concentrations tended to be negatively associated with PEF, and positively associated with the prevalence of phlegm. In two pollutant models, PM10 effect-estimates on phlegm prevalence were reduced and lost significance, whereas the effect-estimates of iron or silicon remained essentially unchanged. The effects of silicon and iron could not be separated. In conclusion, this study provides only weak support for the hypothesis that daily fluctuations in soluble elemental concentrations in ambient particulate matter are responsible for acute health effects.  相似文献   
609.
Why is Warfarin Underutilized in Patients with Atrial Fibrillation?   总被引:3,自引:0,他引:3  
BACKGROUND: Identification of patients at risk for PAF recurrence after AP ablation is important because of the necessity for additional therapies. OBJECTIVES: To determine whether Maximum P-wave duration (Pmax) and P-wave dispersion (Pd ) detected on surface ECG after successful accessory pathway (AP) ablation can predict the recurrence of paroxysmal atrial fibrillation (PAF). METHODS: Seventy-eight patients with Wolff-Parkinson-White (WPW) syndrome who had at least one documented PAF episode and underwent catheter ablation were enrolled. Pmax, minimum P-wave duration (Pmin) and Pd were determined on a surface ECG recorded on a high resolution computer screen on day 2 after ablation of the AP. RESULTS: There was no significant difference in terms of basic clinical data and electrophysiological findings between patients with (Group-1, n = 19) and without (Group-2, n = 59) recurrence of PAF during follow-up of 21 +/- 10 months. Pmax and Pd were significantly higher in Group-1 than Group-2 (120 +/- 15 vs. 96 +/- 10 ms and 47 +/- 12 vs. 25 +/- 7 ms, respectively; p < 0.001 for both). Pmin didn't differ significantly. A Pmax value of > or = 103 ms separated Group-1 from Group-2 with a sensitivity of 84.2%, specificity of 72.9%, positive predictive value of 50%, and negative predictive value of 93.5%. A Pd value of > or = 32.5 ms separated Group-1 from Group-2 with a sensitivity of 89.5%, specificity of 84.7%, positive predictive value of 65.4%, and negative predictive value of 96.2%. Pmax (p < 0.010) and Pd (p < 0.001) were found to be significant univariate predictors of PAF, whereas only Pd remained significant in multivariate analysis (p = 0.037). CONCLUSION: Pd > or = 32.5 ms and Pmax > or = 103.0 ms predict the recurrence of PAF after ablation with acceptable positive and negative predictive values. Pd > or = 32.5 ms is an independent predictor of recurrence of PAF after catheter ablation in patients with WPW syndrome.  相似文献   
610.
The use of complementary and alternative medicine (CAM) therapies is widespread in many chronic illnesses, including human immunodeficiency virus (HIV) infection. The objective of this study was to determine the impact of increasingly effective antiretroviral therapy on the use of CAM in an HIV-positive patient population. A written survey was given to 191 HIV-positive outpatients. Participation was voluntary and anonymous. One hundred twenty-eight patients (67%) used CAM at some time to control HIV and 76 (40%) of the patients were currently using CAM. The major forms of CAM used were exercise (43%), lifestyle changes (38%), dietary supplements (37%), counseling (27%), herbal medications (26%), megavitamins (24%), and prayer therapy (24%). One hundred forty-one patients (74%) used a protease inhibitor medication, 28 (15%) used a protease inhibitor sparing regime, and 22 (11%) had no current or prior antiretroviral use. Eighty-two (43%) patients indicated that their doctor knew they used CAM and 56 patients (29%) received their information about CAM from a doctor or other health care professional. Of 128 patients who used CAM, 90 (70%) felt CAM improved their quality of life. Income of $15,000 or more per year and discontinuation of medications by patients for any reason in the past were the best predicators of CAM use for patients in general and also those on protease inhibitor therapy. CD(4) count, educational status, year of HIV diagnosis, and martial status were not effective predictors of CAM use. Use of CAM remains widespread among patients with HIV infection even with the availability of effective, yet noncurative antiretroviral therapy and does not correlate with type of antiretroviral therapy used or clinical status.  相似文献   
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