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排序方式: 共有548条查询结果,搜索用时 31 毫秒
81.
82.
Twenty-three apparently normal untrained men aged 20--55 participated in a 4-month self-regulated training programme ending in a marathon run. Fasting plasma and lipoprotein lipid concentrations, adipose tissue lipoprotein lipase activity, anthropometric data, alcohol consumption, smoking habits, weekly mileage run and performance on a bicycle ergometer were recorded before and after the training period. Training induced an increase in high density lipoprotein cholesterol (HDL-C) concentration which was not directly related to concomitant decreases in mean very low density lipoprotein cholesterol (VLDL-C) concentration or mean total skinfold thickness. The degree of the changes in VLDL lipids and HDL-C levels were related to pretraining values, and changes in HDL-C and VLDL triglycerides (VLDL-TG) were also associated. Initial total skinfold thickness correlated inversely with the change in VLDL-TG levels during training. The pretaining concentration of VLDL-C was related to the corresponding value for HDL-C after training. The magnitude of exercise-induced changes in VLDL-C and HDL-C levels are more related to pre-training levels than to changes in measured exercise parameters, indices of obesity or adipose tissue lipoprotein lipase activity. However, the level of adiposity of subjects at the beginning of the study influenced the response of VLDL-TG levels to increased physical activity. The data suggest that VLDL contributes to the increase in HDL-C levels with exercise but is not the major source of the increment. 相似文献
83.
Pathological personality item responses have been shown to relate to the social desirability scale values of test items. It was hypothesized that both social desirability and pathological item-response frequency might vary as a function of the time permitted to answer test items. Two groups of Ss were administered the items of the Maslow, Birch, Honigman, McGrath, Plason, and Stein Security-Insecurity Inventory. Social desirability scale values for the items were established. Maximal reading time required for each item was also determined, and both groups were permitted to view each item for the same established length of time. 1 group was allowed 2 sec., the other group 10 sec. for each response. It was observed that time pressure reduced the number of pathological item responses, and that items scaled either high or low in social desirability tended to be answered in the socially desirable direction under time pressure. Females generally provided more critical or pathological item responses than did males. (24 ref.) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
84.
HA Liebman N Kashani D Sutherland W McGehee AL Kam 《Canadian Metallurgical Quarterly》1998,115(4):830-834
BACKGROUND & AIMS: Thromboembolic disease is a significant cause of morbidity and mortality in patients with inflammatory bowel disease (IBD). The aim of this study was to determine the incidence and possible association of the factor V Leiden mutation with the development of thrombosis in patients with IBD. METHODS: This retrospective study included 11 patients with IBD and arterial or venous thrombosis and 51 patients with IBD and no history of thrombosis who were matched for age, sex, ethnic/racial origin, and type of IBD (controls). The presence of the factor V Leiden mutation was determined by coagulation assay and confirmed by a polymerase chain reaction method. RESULTS: Four of 11 IBD patients (36%) with thrombosis and 2 of 51 IBD controls (4%) were heterozygotes for the factor V Leiden mutation (relative risk, 14.00; 95% confidence interval, 1.55-169.25; P = 0.009, Fisher exact test). All thrombotic events in the patients with activated protein C resistance were venous with a calculated prevalence of 50% (4 of 8 patients) and a relative risk of venous thrombosis in IBD patients with factor V Leiden of 23 (95% confidence interval, 2-294; P = 0.005). CONCLUSIONS: In patients with IBD, inheritance of the factor V Leiden mutation results in a significant increased risk of venous thrombosis. 相似文献
85.
Reinjection of a second dose of Tl-201 before redistribution imaging has significantly improved the ability of myocardial perfusion imaging to detect jeopardized myocardium. However, PET studies and the results from coronary artery angioplasty and bypass surgery indicate that Tl-201 studies still underestimate the number of ischemic areas at stress that represent viable myocardium. To determine whether an imaging protocol using an early reinjection of Tl-201 immediately after acquisition of the stress images would improve the detection of jeopardized myocardium, 138 patients were studied with an early reinjection protocol and the incidence and magnitude of reversible defects were compared by SPECT to a second group of 143 patients who underwent the standard late reinjection protocol. Two observers independently evaluated 19 standard myocardial segments by visual examination in each patient. They determined the presence or absence of reversible defects, and, when present, their magnitude. The frequency of reversible defects always was less with early reinjection compared to the standard late reinjection; the difference reached statistical significance for one of the two observers (P < 0.05). It is concluded that early reinjection of Tl-201 in myocardial perfusion imaging does not increase and may decrease the sensitivity of the study for jeopardized myocardium. 相似文献
86.
87.
A.J. Bates M.A. Sutherland F. Chapple S.K. Dowling A.P. Johnson B. Saldias J. Singh 《Journal of dairy science》2019,102(3):2492-2506
Anesthesia of the horn bud for calf disbudding commonly is attained by injection of local anesthetic over branches of the cornual nerve, with anesthesia achieved in 3 to 20 min. With experienced and trained staff, this method is effective in 88 to 100% of calves. Variability in response and time of onset can compromise calf welfare if calves are disbudded before anesthesia is attained. Proposed legislative reliance on effective local anesthetic as the minimal method of pain relief for calves at disbudding means that administration of local anesthetic must achieve a repeatable level and rapid onset of analgesia. We describe an alternative method of local anesthesia administration that uses local site infiltration of anesthetic over the horn bud. However, this method has not yet been scientifically validated. This study assessed differences between disbudding using the cornual nerve block and disbudding with local anesthesia administered by local site infiltration. Efficacy of local anesthesia was assessed at 30-s intervals after administration by absence of reaction to 3 consecutive needle pricks over the horn buds. Behavior indicating pain was assessed during disbudding and scored from 0 to 3. Calf behavior was also recorded for 3 h after disbudding. Accelerometer data loggers were fitted to each calf for 24 h before and after disbudding to assess lying and standing times. Median time to cutaneous desensitization for local infiltration was 60 s compared with 225 s for cornual nerve block, and the variance in time to desensitization was less with local infiltration. Calves disbudded under cornual block had a larger behavioral response (indicated by a graded aversive body reaction) than calves disbudded under local infiltration. A multivariable model predicted that the mean body reaction score would be 0.6 for calves disbudded under local infiltration and 1.2 for calves disbudded under cornual block. There was no difference in any behaviors between the treatment groups in the 3 h after disbudding. Method of analgesia had no effect on lying time over the 24 h after disbudding. In this study, local infiltration was at least as effective in providing analgesia for disbudding as the cornual nerve block. Our results suggest that a more consistent, effective level of analgesia during disbudding was achieved using local infiltration and that there was no difference in postoperative expressions of pain. 相似文献
88.
Dylan Sutherland John Anderson Peter Hertenstein 《Management International Review》2018,58(6):911-933
Do emerging market MNEs acquire strategic assets in psychically distant developed markets to augment the firm-specific advantages they lack? This question is central to current conceptual discussion of their FDI strategies. To date, however, empirical testing has focused on emerging market MNE FDI location choices in isolation to indirectly infer facts about strategic asset seeking orientation. There are two weaknesses with this approach. First, comparative analysis with developed market MNEs is limited. Second, the focus on geographical location choices does not account for important direct, firm-level evidence on the strategic assets found in foreign subsidiaries. To address these gaps, we first undertake a comparative location choice study of Chinese MNE and developed market MNE FDI in the US. Second, we test corresponding firm-level US subsidiary data using logit modelling to explore whether there are differences between Chinese and developed market MNEs. Our results indicate similarities, rather than differences, in the strategic asset seeking behavior of Chinese and developed market MNEs. This calls into question whether theoretical extension is necessary to explain the behavior of emerging market MNEs as well as the value of indirect, location choice approaches to the analysis of strategic asset seeking FDI. 相似文献
89.
D. P. Adler W. W.-S. Hii D. J. Michalek J. W. Sutherland 《Machining Science and Technology》2013,17(1):23-58
ABSTRACT Cutting fluids have seen extensive use and have commonly been viewed as a required addition to high productivity and high quality machining operations. Cutting fluid related costs and health concerns associated with exposure to cutting fluid mist and a growing desire to achieve environmental sustainability in manufacturing have caused industry and academia to re-examine the role of these fluids and quantify their benefits. This work summarizes the traditional purposes of cutting fluids and reports on recent analytical and experimental research to critically examine these functions. To minimize or even eliminate the concerns associated with cutting fluid usage, several recent and novel approaches have been proposed and are examined. 相似文献
90.
Tinnion E Jowitt F Clarke-O'Neill S Cottenden AM Fader M Sutherland I 《Proceedings of the Institution of Mechanical Engineers. Part H, Journal of engineering in medicine》2003,217(4):291-296
Continence difficulties affect the lives of a substantial minority of the population. Women are far more likely than men to be affected by urinary incontinence but the range of management options for them is limited. There has been considerable interest in developing an external urine collection system for women but without success to date. This paper describes the development and preliminary clinical testing of an active urine collection device (AUCD), which could provide a solution for sufferers. The device uses stored vacuum, protected by a high bubble point filter, to remove urine as quickly as it is produced. This allows a small battery-operated pump to provide the required vacuum, enabling the device to be portable. Two different types of non-invasive patient/device interface were developed, and tested by volunteers: urinal and small pad. The slimline urinal was popular with users although liquid noise was a problem. The pad interface was successful on occasions but further work is necessary to produce a reliable pad. This study has successfully demonstrated that a prototype AUCD liquid handling system can remove urine at clinically relevant flowrates. While further development is required, volunteer tests have shown that the AUCD could be a useful advance in continence management. 相似文献