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31.
PURPOSE: Aerobic exercise may influence gallstone disease pathogenesis through its effect on gallbladder motility. The purpose of this investigation was to examine the effects of exercise training on gallbladder emptying in obese women. METHODS: Twenty-seven obese subjects were randomized into one of two groups: exercise (E) (five 45-min brisk walking sessions per week at 75.2 +/- 0.5% of maximum heart rate) and controls (C). Gallbladder function via cholescintigraphy, cardiorespiratory fitness, and body composition were measured in all subjects before and after a 12-wk intervention period. In each cholescintigraphy trial subjects ingested an 8-oz liquid meal 45 min after injection of 99mTc disofenin to promote gallbladder emptying. Gallbladder areas were then scanned for 60 s and then every 5 min for 60 min. RESULTS: VO2max increased significantly by 9% for E when compared with that for C (P < 0.001). Within E postprandial gallbladder ejection fraction (EF) increased significantly after training (39.5 +/- 4.9% to 54.7 +/- 6.5%, P < 0.05); however, this 15.2% increase in EF was not significantly greater than the change reported in the controls. CONCLUSIONS: Results indicate that 12 wk of moderate exercise training does improve cardiorespiratory fitness but does not significantly effect gallbladder emptying in obese women.  相似文献   
32.
In a combined (cross-sectional and longitudinal) study, the serum concentration of laminin P1 was measured by radioimmunoassay in 16 patients with benign inflammatory bladder disorders and 47 patients with transitional cell carcinoma of the bladder. The results were compared with the serum laminin P1 values in 50 healthy control subjects. In the cross-sectional study, the mean value of serum laminin P1 was significantly higher in bladder cancer patients than either the controls (p < 0.0001) or patients with benign inflammatory bladder disorders (p < 0.001). Similarly, the mean values of all different stages of grades of the tumor were significantly higher than either the controls or patients with benign inflammatory disorders. Progressive increase in the mean values of serum laminin P1 could also be found with deterioration of the stage or grade of the tumor. However, the difference between the mean values of the different cancer stages or grades did not reach statistical significance. In the longitudinal study, no significant difference could be detected between the mean values of patients with superficial tumor recurrence and those with remission of the disease (p > 0.5). Nevertheless, in the invasive cancer group, the levels of serum laminin P1 were directly proportional with progression of the disease (Z = 2.94; p < 0.01).  相似文献   
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Muscle damage and perceived soreness following the 160-km Western States Endurance Run were related to changes in plasma cytokines and use of nonsteroidal anti-inflammatory drugs (NSAIDS). Subjects included 60 ultramarathoners (mean+/-SE, age 45.3 +/- 1.1 years) who finished the race in under 30 h (26.3 +/- 0.4 h). Blood samples were collected the morning prior to and immediately following the race, and subjects recorded muscle soreness during the week following the race using a 10-point Likert scale (DOMS). Seven plasma cytokines were measured including IL-6, IL-10, IL-8, IL-1ra, granulocyte colony-stimulating factor (G-CSF), monocyte chemotactic protein 1 (MCP-1), and macrophage inflammatory protein 1beta (MIP-1beta). Cytokine changes were compared between NSAID users and nonusers, and correlated with creatine phosphokinase (CPK) and DOMS. Significant increases were measured for all seven cytokines, with the greatest fold increases seen for IL-6 (125x), IL-10 (24x), and G-CSF (12x). CPK was correlated with changes in IL-6, G-CSF, IL-10, IL-1ra, and MCP-1 (r = .49-.68), (P < .001), but not IL-8 or MIP-1beta. DOMS averaged 7.1 +/- 0.3 the day after the race, and 5.0 +/- 0.3, 2.5 +/- 0.2, and 1.6 +/- 0.1 3 days, 5 days, and 7 days post-race, respectively, and each was correlated with CPK (r = .40-.63, P < .001) and changes in IL-6, G-CSF, IL-10, and MCP-1 (r = .28-.77, P < .05). A comparison of NSAID users (72% of athletes) and nonusers showed no differences in CPK or DOMS, but did reveal greater increases in five of seven cytokines in the NSAID users (P < .05). In conclusion, muscle damage in athletes competing in a 160-km race was significantly correlated with post-race DOMS and increases in five of seven cytokines. NSAID users did not experience a reduction in muscle damage or DOMS, but did have higher post-race plasma levels in five of seven cytokines.  相似文献   
35.
PURPOSE: To evaluate the accuracy of leg-to-leg bioelectrical impedance analysis (BIA) in assessing fat-free mass (FFM) using the TBF-300WA in comparison with hydrostatic weighing (HW) and skinfolds (SK) in high-school (HS) wrestlers in a hydrated state. METHODS: Body composition was determined by BIA, HW, and three-site SK in 129 HS wrestlers (mean +/- SD, age: 15.5 +/- 1.3, height 1.70 +/- 0.08 m, body mass 65.6 +/- 13.1 kg). For all methods, body density (Db) was converted to percent body fat (%BF) using the Brozek equation. Hydration state was quantified by evaluating urine specific gravity. RESULTS: There were no significant differences for estimated FFM between BIA (56.9 +/- 8.4 kg) and HW (56.2 +/- 9.9 kg) or between SK (56.1 +/- 8.9 kg) and HW. The standard errors of estimate for FFM with HW as the reference method were 3.64 kg for BIA and 1.97 kg for SK. Significant correlations were found for FFM between HW and BIA (r = 0.93, P < 0.001), and between HW and SK (r = 0.98, P < 0.001). The FFM difference between BIA and HW was significantly correlated with the FFM average of the two methods (r = -0.39, P < 0.001). The FFM difference between SK and HW was also significantly correlated with the FFM average (r = -0.44, P < 0.001). CONCLUSIONS: This study demonstrates that SK should be considered as the preferred field method of estimating the FFM of HS wrestlers because of its greater individual precision than the leg-to-leg BIA method. Although the BIA is an attractive assessment tool and easy to use, it should be recommended as an alternative to the SK method only when trained skinfold technicians are not available.  相似文献   
36.
OBJECTIVE: To determine whether urine VEGF is elevated in women with endometriosis. DESIGN: Prospective observational study. SETTING: Tertiary care government and private hospitals. PATIENT(S): During laparoscopy for pelvic pain or infertility, urine was collected and possible endometriosis lesions were excised. Of 62 women, 40 had histology-proven endometriosis and 22 had no histological proof of the disease. INTERVENTION: None. MAIN OUTCOME MEASURE(S): Urine VEGF-A(121, 165) was measured and compared in women with and without biopsy-proven endometriosis. RESULT(S): Urine VEGF levels corrected for creatinine excretion were similar in women with (83.6 +/- 11.3 pg/mg Cr) and without (88.5 +/- 10.4 pg/mg Cr) endometriosis (P =.77). The frequency distribution of urine VEGF measurements for women with and without endometriosis was similar. No significant difference was noted in urine VEGF levels when comparing endometriosis stages or in those with endometriomas compared to controls. Urine VEGF did not vary significantly over the menstrual cycle or between groups by cycle phase. No cutoff point discriminated individuals with and without the condition. CONCLUSION(S): It is unlikely that urine VEGF-A(121, 165), as measured in this study, will be a useful non-invasive marker for endometriosis.  相似文献   
37.
The influence of 6% carbohydrate ingestion and age on PHA-induced lymphocyte proliferation and in vitro cytokine production was studied in 48 runners following a competitive marathon. Runners were randomly assigned to carbohydrate (C; n = 23) and placebo (P; n= 25) groups, with blood samples taken before, immediately after, and 1.5 hr post-race. C versus P ingestion resulted in higher plasma glucose, lower plasma cortisol, reduced neutrophilia, and monocytosis during recovery, but had no effect on the post-exercise reduction in T-lymphocytes or NK cells, or on race times. No group differences were observed for PHA-induced lymphocyte proliferation or cytokine production. However, for all subjects combined, lymphocyte proliferation and IFN-gamma secretion decreased significantly below pre-race values by 1.5 hr of recovery, and these were negatively correlated with plasma cortisol. Young (<50 years; n = 36) and old (>or=50 years; n = 12) runners exhibited parallel post-race declines in lymphocyte proliferation and IFN-gamma secretion, with the older group exhibiting a 33-59% lower proliferation at each time point. In conclusion, PHA-induced lymphocyte proliferation and cytokine production decreased significantly following a marathon, and this decrease was strongly linked to cortisol and only partially linked to T-cell changes. This decrease occurred in both younger and older runners and was not influenced by carbohydrate.  相似文献   
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Aim of this paper is to describe the technical main features that characterize Spiral Computed Tomography (CT) angiography. In particular, the technical features of the three main generations of single, four, and sixteen multislice scanners have been analised. Particular attention have been addressed to scan and reconstruction parameters, and to the geometry of contrast material related to angiographic scan. Guidelines for the different generations of CT scanner have been extracted to give the radiologist a platform for diagnostic questions.  相似文献   
40.
PURPOSE: To learn whether preclinical primary care preceptorships resulted in demonstrable clinical performance benefits to medical students. METHOD: This was a retrospective cohort study of 267 medical students who elected and 310 students who did not elect to take a four-week primary care preceptorship following the first year of training at the University of Texas Medical School at Houston in 2001-2003. Outcome variables were the students' performances on a written examination testing their integration of basic science and fundamentals of clinical medicine and performances on a comprehensive objective structured clinical examination (OSCE). After adjusting for factors that might have explained differences in the students' performances, logistic regression models were used to assess the association of the outcome variables with participation in a preceptorship. RESULTS: Students who participated in any one of the preceptorships performed better on the OSCE and on the fundamentals of clinical medicine examination than students who did not participate (p < .01). Students who participated in the family medicine or pediatric preceptorship scored higher on an OSCE (odds ratio [OR], 1.67; 95% confidence interval [CI], 1.01-2.78 and OR, 2.26; 95% CI, 1.18-4.36, respectively) than those students who did not participate in a preceptorship. Students who participated in the internal medicine preceptorship scored higher on the fundamentals of clinical medicine examination (OR, 3.18; 95% CI, 1.92-5.23). CONCLUSIONS: Preliminary evidence indicates that a short preclinical primary care preceptorship can help medical students to consolidate and integrate the fundamental cognitive and clinical skills they will apply during the clinical years of medical training.  相似文献   
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