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101.
AR Weinstein HD Sesso IM Lee NR Cook JE Manson JE Buring JM Gaziano 《JAMA : the journal of the American Medical Association》2004,292(10):1188-1194
CONTEXT: Physical inactivity and body mass index (BMI) are established independent risk factors in the development of type 2 diabetes; however, their comparative importance and joint relationship with diabetes are unclear. OBJECTIVE: To examine the relative contributions and joint association of physical activity and BMI with diabetes. DESIGN, SETTING, AND PARTICIPANTS: Prospective cohort study of 37 878 women free of cardiovascular disease, cancer, and diabetes with 6.9 years of mean follow-up. Weight, height, and recreational activities were reported at study entry. Normal weight was defined as a BMI of less than 25; overweight, 25 to less than 30; and obese, 30 or higher. Active was defined as expending more than 1000 kcal on recreational activities per week. MAIN OUTCOME MEASURE: Incident type 2 diabetes, defined as a new self-reported diagnosis of diabetes. RESULTS: During the follow-up, 1361 cases of incident diabetes occurred. Individually, BMI and physical activity were significant predictors of incident diabetes. Compared with normal-weight individuals, the multivariate-adjusted hazard ratio (HR) was 3.22 (95% confidence interval [CI], 2.69-3.87) for overweight individuals and 9.09 (95% CI, 7.62-10.8) for obese individuals. For overall activity (kilocalories expended per week), compared with the least active first quartile, the multivariate-adjusted HRs were 0.91 (95% CI, 0.79-1.06) for the second quartile, 0.86 (95% CI, 0.74-1.01) for the third, and 0.82 (95% CI, 0.70-0.97) for the fourth (P for trend =.01). In the combined analyses, overweight and obese participants, whether active or inactive, had significantly elevated risks, compared with normal-weight active individuals. The multivariate-adjusted HRs were 1.15 (95% CI, 0.83-1.59) for normal-weight inactive, 3.68 (95% CI, 2.63-5.15) for overweight active, 4.16 (95% CI, 3.05-5.66) for overweight inactive, 11.5 (95% CI, 8.34-15.9) for obese active, and 11.8 (95% CI, 8.75-16.0) for obese inactive participants. CONCLUSIONS: Although BMI and physical inactivity are independent predictors of incident diabetes, the magnitude of the association with BMI was greater than with physical activity in combined analyses. These findings underscore the critical importance of adiposity as a determinant of diabetes. 相似文献
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Percutaneous dilation of benign biliary strictures 总被引:1,自引:0,他引:1
Moore AV Jr; Illescas FF; Mills SR; Wertman DE; Heaston DK; Newman GE; Zuger JH; Salmon RB; Dunnick NR 《Radiology》1987,163(3):625-628
Percutaneous balloon dilation of benign biliary strictures was successful in 15 of 18 patients in whom the procedure was attempted. Successful dilation was achieved in nine of 11 patients who had biliary enteric strictures, with follow-up of 22-55 months (mean, 35.4 months) after catheter removal in seven patients. Five of six strictures in the biliary tree that developed after surgery were successfully dilated, with long-term follow-up available in two patients (58 and 42 months). A patient with an inflammatory common bile duct stricture that was successfully dilated was followed up for 18 months. Percutaneous dilation of biliary tract strictures is a promising technique with good long-term results and may be the initial treatment of choice in biliary stricture management. 相似文献
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To determine the value of the initial phase of the Tc-99m DTPA renogram in the direct estimation of relative renal blood flow in dogs, the ratios of the slopes of renal time-activity curves were compared with the ratios of measured blood flow. Radionuclide results were dependent on region-of-interest (ROI) and background ROI assignment, and correlated well with measured relative flow only with a maximum renal outline region. Curve slope ratios correlated well with measured flow ratios with and without background correction, while 1- to 2-minute uptake ratios correlated well only when corrected for background. 相似文献
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Jenna D. Strickland William R. Lefew James Crooks Diana Hall Jayna NR Ortenzio Kevin Dreher 《Nanotoxicology》2016,10(5):619-628
Nanoparticles (NPs) may translocate to the brain following inhalation or oral exposures, yet higher throughput methods to screen NPs for potential neurotoxicity are lacking. The present study examined effects of 5 CeO2 (5– 1288?nm), and 4 TiO2 (6–142?nm) NPs and microparticles (MP) on network function in primary cultures of rat cortex on 12 well microelectrode array (MEA) plates. Particles were without cytotoxicity at concentrations ≤50?µg/ml. After recording 1?h of baseline activity prior to particle (3–50?µg/ml) exposure, changes in the total number of spikes (TS) and # of active electrodes (#AEs) were assessed 1, 24, and 48?h later. Following the 48?h recording, the response to a challenge with the GABAA antagonist bicuculline (BIC; 25?µM) was assessed. In all, particles effects were subtle, but 69?nm CeO2 and 25?nm TiO2 NPs caused concentration-related decreases in TS following 1?h exposure. At 48?h, 5 and 69?nm CeO2 and 25 and 31?nm TiO2 decreased #AE, while the two MPs increased #AEs. Following BIC, only 31?nm TiO2 produced concentration-related decreases in #AEs, while 1288?nm CeO2 caused concentration-related increases in both TS and #AE. The results indicate that some metal oxide particles cause subtle concentration-related changes in spontaneous and/or GABAA receptor-mediated neuronal activity in vitro at times when cytotoxicity is absent, and that MEAs can be used to screen and prioritize nanoparticles for neurotoxicity hazard. 相似文献
110.
Heidenreich JW Higdon TA Kern KB Sanders AB Berg RA Niebler R Hendrickson J Ewy GA 《Resuscitation》2004,62(3):283-289
The Guidelines 2000 for CPR and ECC recommend for single lay-rescuers performing basic life support, "two quick breaths followed by 15 chest compressions", repeated until professional help arrives. It is uncertain that this can actually be accomplished by the majority of lay rescuers. We evaluated 53 first-year medical students after completing BLS CPR training to determine if they could deliver the goal of 80 compressions per minute when following this AHA BLS recommendation. Alternatively, a simplified technique of uninterrupted chest compression (UCC) BLS CPR was also taught and compared with standard BLS CPR (STD). The mean number of chest compressions/minute delivered with AHA BLS CPR was only 43 +/- 1 immediately after initial training and 49 +/- 2 when tested 6 months later. Uninterrupted chest compression BLS resulted in 113 +/- 2 compressions/min delivered immediately after training and 91 +/- 4 six months later (STD versus UCC; P < 0.0001). The mean length of time needed to provide the two breaths during STD-CPR was 14 +/- 1 and 12 +/- 1s (immediately after first training and six months after training). For STD-CPR, the mean minute ventilation was poor immediately after initial training (3.3 +/- 0.3 l/min) and further declined (1.9 +/- 0.4 l/min) at 6 months (P = 0.003). For single rescuer basic cardiopulmonary resuscitation, motivated BLS CPR-trained medical students take nearly as long as previously reported for middle-aged lay individuals to deliver these "two quick breaths". The "Guidelines 2000" recommendation for "two quick breaths" is an oxymoron, as it averages more than 13s. New recommendations for single-rescuer CPR should be considered that emphasize uninterrupted chest compressions. 相似文献