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G J Pucak N D Lehner T B Clarkson B C Bullock H B Lofland 《Experimental and molecular pathology》1973,18(1):32-49
Spider monkeys (Ateles sp.) were evaluated for their usefulness in research on atherosclerosis. These animals became only slightly hypercholesterolemic (increase from control serum cholesterol concentrations of about 200 mg/100 ml to about 290 mg/100 ml) when fed diets containing 1 mg of cholesterol/kcal (diets shown previously to produce marked hypercholesterolemia in most species of nonhuman primates).Both control and experimental monkeys had aortic fatty streaks and occasional lesions of the major branches of the coronary arteries. Cholesterol feeding for up to 48 months exacrebated the lesions only slightly.Biochemically, the atherosclerotic lesions of spider monkeys, as compared with other primates, have relatively less cholesterol ester and markedly more phospholipid. 相似文献
125.
Precision and accuracy of an ankle-worn accelerometer-based pedometer in step counting and energy expenditure 总被引:1,自引:0,他引:1
Foster RC Lanningham-Foster LM Manohar C McCrady SK Nysse LJ Kaufman KR Padgett DJ Levine JA 《Preventive medicine》2005,41(3-4):778-783
BACKGROUND: Walking is a widely used approach to increase physical activity levels in obese patients. In this paper, we investigate the precision and accuracy of an ankle-worn dual-axis accelerometer (Stepwatch) and investigate its potential application as a predictor of energy expenditure. METHODS: Twenty healthy subjects (10 lean, 10 obese) wore spring-levered (Accusplit), piezoelectric (Omron HF-100), and Stepwatch pedometers. Subjects walked on a treadmill at 1, 2, and 3 mph and in a hallway at 1 and 1.85 mph, during which energy expenditure was measured. RESULTS: The Stepwatch counted 99.7 +/- 0.67% (mean +/- SEM) of the manual counts. In comparison, the Omron pedometer counted 61 +/- 3.3% and the Accusplit counted 26 +/- 2.8% of the manual counts at 1 mph although all pedometers were accurate (> 98% of counts) at 3 mph. In repeated measures, the Stepwatch produced negligible variance (SD = 0.36) over all speed whereas the other pedometers showed a large amount of variance at all speed (SD = 4-13). Stepwatch counts were predictive of walking energy expenditure corrected by weight (r2 > 0.8). CONCLUSION: The counts from the Stepwatch were virtually identical to the manual counts from a trained investigator and provided a reliable predictor of walking energy expenditure. 相似文献
126.
Cell proliferation and neuronal differentiation in the dentate gyrus in juvenile and adult rats following traumatic brain injury 总被引:3,自引:0,他引:3
Sun D Colello RJ Daugherty WP Kwon TH McGinn MJ Harvey HB Bullock MR 《Journal of neurotrauma》2005,22(1):95-105
It is well known that the cognitive functions of juveniles recover to a greater extent than adult patients following traumatic brain injury (TBI). The exact mechanisms underlying this age-related disparity are unknown; however, we speculate that this improved recovery in juveniles following TBI may be associated with an endogenous neurogenic response in the hippocampus. We, therefore, examined the effects of TBI on cellular proliferation and differentiation in the dentate gyrus (DG) of the hippocampus in juvenile and adult rats following lateral fluid percussion injury (FPI). The temporal profile of the injury-induced proliferative response was determined using BrdU labeling at varying survival times. The differentiation of these newly generated cells was investigated using cell-type specific markers. We found that, following injury, there was a significant increase in cell proliferation in the DG in both injured juveniles and adults at 2 days post injury when compared to shams. When comparing the extent of cell proliferation between juveniles and adults following TBI, the absolute number of cells generated in the subgranular zone (SGZ) was far greater in the juveniles. Moreover, the percentage of newly generated cells in the SGZ that differentiated into neurons was nearly two times higher in the juveniles as compared to adults. Conversely, more glial differentiation was observed in the DG of adult rats. These findings provide compelling evidence that age-related differences in the neurogenic response to injury may underlie the differences observed in cognitive recovery in juvenile mammals as compared to adults following TBI. 相似文献
127.
Blumenthal JA Sherwood A Babyak MA Watkins LL Waugh R Georgiades A Bacon SL Hayano J Coleman RE Hinderliter A 《JAMA》2005,293(13):1626-1634
Context Observational studies have shown that psychosocial factors are associated with increased risk for cardiovascular morbidity and mortality, but the effects of behavioral interventions on psychosocial and medical end points remain uncertain. Objective To determine the effect of 2 behavioral programs, aerobic exercise training and stress management training, with routine medical care on psychosocial functioning and markers of cardiovascular risk. Design, Setting, and Patients Randomized controlled trial of 134 patients (92 male and 42 female; aged 40-84 years) with stable ischemic heart disease (IHD) and exercise-induced myocardial ischemia. Conducted from January 1999 to February 2003. Interventions Routine medical care (usual care); usual care plus supervised aerobic exercise training for 35 minutes 3 times per week for 16 weeks; usual care plus weekly 1.5-hour stress management training for 16 weeks. Main Outcome Measures Self-reported measures of general distress (General Health Questionnaire [GHQ]) and depression (Beck Depression Inventory [BDI]); left ventricular ejection fraction (LVEF) and wall motion abnormalities (WMA); flow-mediated dilation; and cardiac autonomic control (heart rate variability during deep breathing and baroreflex sensitivity). Results Patients in the exercise and stress management groups had lower mean (SE) BDI scores (exercise: 8.2 [0.6]; stress management: 8.2 [0.6]) vs usual care (10.1 [0.6]; P = .02); reduced distress by GHQ scores (exercise: 56.3 [0.9]; stress management: 56.8 [0.9]) vs usual care (53.6 [0.9]; P = .02); and smaller reductions in LVEF during mental stress testing (exercise: 0.54% [0.44%]; stress management: 0.34% [0.45%]) vs usual care (1.69% [0.46%]; P = .03). Exercise and stress management were associated with lower mean (SE) WMA rating scores (exercise: 0.20 [0.07]; stress management: 0.10 [0.07]) in a subset of patients with significant stress-induced WMA at baseline vs usual care (0.36 [0.07]; P = .02). Patients in the exercise and stress management groups had greater mean (SE) improvements in flow-mediated dilation (exercise: mean [SD], 5.6% [0.45%]; stress management: 5.2% [0.47%]) vs usual care patients (4.1% [0.48%]; P = .03). In a subgroup, those receiving stress management showed improved mean (SE) baroreflex sensitivity (8.2 [0.8] ms/mm Hg) vs usual care (5.1 [0.9] ms/mm Hg; P = .02) and significant increases in heart rate variability (193.7 [19.6] ms) vs usual care (132.1 [21.5] ms; P = .04). Conclusion For patients with stable IHD, exercise and stress management training reduced emotional distress and improved markers of cardiovascular risk more than usual medical care alone. 相似文献
128.
K. N. Bullock 《Postgraduate medical journal》1982,58(675):35-36
A case is reported of chronic calculous parotitis beginning in a 12-month-old child. Further questioning revealed a history of parotid calculi in her mother and submandibular calculi in her maternal grandmother. The features which indicate the diagnosis of parotid calculous disease are discussed and, from a review of the literature, some observations are made on management. 相似文献
129.