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61.
This study utilizes a psychophysical approach to examine the effects on
carrying capacity for bi-manual carrying tasks involving different handle positions and
carrying ranges. A total of 16 female subjects participated in the experiment in groups of
two people, and each group of subjects performed the tasks in a random order with 12
different combinations of carrying task. The independent variables are handle position
(upper, middle, lower) and carrying range (F–F: floor height carried to floor height, F–W:
floor height carried to waist height, W–W: waist height carried to waist height, W–F:
waist height carried to floor height), the dependent variable is the maximum acceptable
carried weight (MAWC), heart rate (HR), and the rating of perceived exertion (RPE). The
results show that the handle position has a significant effect on MAWC and overall RPE but
no significant effect on HR. Carrying range has a significant effect on the MAWC and HR,
but no significant effect on overall HR. The handle position and carrying range have a
significant interaction on the MAWC and HR. The RPE for different body parts shows
significant differences, and the hands feel the most tired. Overall, this study confirms
that the lower handle position with the W–W carrying range is the best combination for a
two-person carrying task. 相似文献
62.
This meta-analysis examined whether early decompressive craniectomy (DC) can improve control of intracranial pressure (ICP) and mortality in patients with traumatic brain injury (TBI).Medline, Cochrane, EMBASE, and Google Scholar databases were searched until May 14, 2015, using the following terms: traumatic brain injury, refractory intracranial hypertension, high intracranial pressure, craniectomy, standard care, and medical management. Randomized controlled trials in which patients with TBI received DC and non-DC medical treatments were included.Of the 84 articles identified, 8 studies were selected for review, with 3 randomized controlled trials s having a total of 256 patients (123 DCs, 133 non-DCs) included in the meta-analysis. Patients receiving DC had a significantly greater reduction of ICP and shorter hospital stay. They also seemed to have lower odds of death than patients receiving only medical management, but the P value did not reach significance (pooled odds ratio 0.531, 95% confidence interval 0.209–1.350, Z = 1.95, P = 0.183) with respect to the effect on overall mortality; a separate analysis of 3 retrospective studies yielded a similar result.Whereas DC might effectively reduce ICP and shorten hospital stay in patients with TBI, its effect in decreasing mortality has not reached statistical significance. 相似文献
63.
Guowei Zhang Fenger Sun Heping Liu Xiaoyan Ren Hong Xu Mingjie Wang Yizheng Fu 《Materials》2021,14(9)
The structural properties, elastic anisotropy, electronic structures and work function of D022-type Al3TM (TM = Sc, Ti, V, Y, Zr, Nb, La, Hf, Ta) are studied using the first-principles calculations. The results indicate that the obtained formation enthalpy and cohesive energy of these compounds are in accordance with the other calculated values. It is found that the Al3Zr is the most thermodynamic stable compound. The mechanical property indexes, such as elastic constants, bulk modulus, shear modulus, Young’s modulus, Poisson’s ratio, and Vickers hardness are systematically explored. Moreover, the calculated universal anisotropic index, percent anisotropy and shear anisotropic factors of D022-type Al3TM are analyzed carefully. It demonstrates that the shear modulus anisotropy of Al3La is the strongest, while that of Al3Ta is the weakest. In particular, the density of states at Fermi level is not zero, suggesting that these phases have metal properties and electrical conductivity. More importantly, the mechanisms of correlation between hardness and Young’s modulus are further explained by the work function. Finally, the experimental design proves that D022-Al3Ta has an excellent strengthening effect. 相似文献
64.
65.
目的:探讨肛肠疾病手术前后肛管直肠压力测定的应用。方法:将2018年5月-2019年5月在上海市松江区方塔中医医院及上海中医药大学附属曙光医院肛肠科行手术治疗的826例肛肠疾病患者作为研究对象,其中,选择性痔上黏膜吻合术246例、单纯外剥内扎术115例、外剥内扎结合内痔套扎术(Automatic Ligation of Hemorrhoids,RPH)153例、低位肛瘘切除术177例、高位肛瘘切开挂线术135例,分别于术前及术后1个月测定肛管直肠压力。结果:选择性痔上黏膜吻合术后直肠静息压、肛管静息压明显低于术前,肛管舒张压高于术前(P<0.05),但肛管最大收缩压与术前相比无明显差异(P>0.05);单纯外剥内扎术术后直肠静息压、肛管静息压明显低于术前,肛管舒张压、肛管最大收缩压明显高于术前(P<0.05);外剥内扎结合内痔套扎术术后直肠静息压、肛管静息压明显低于术前,肛管舒张压、肛管最大收缩压明显高于术前(P<0.05);低位肛瘘切除术术后直肠静息压、肛管静息压、肛管舒张压均高于术前(P<0.05),而肛管最大收缩压与术前相比无明显差异(P>0.05);高位肛瘘切开挂线术术后直肠静息压高于术前,肛管静息压、肛管舒张压低于术前(P<0.05),而与肛管最大收缩压术前相比无明显差异(P>0.05)。结论:肛肠疾病手术前后肛管直肠压力测定的应用效果显著,能准确判断手术效果及患者恢复情况,为医师的进一步诊治奠定了良好基础。 相似文献
66.
67.
目的 探讨膝骨美节炎(KOA)患者美节滑液中IL 17的水平与疾病严重程度的相关性,为临床诊治KOA 提供新思路及新方法。方法 选取2017年1月?2018年12月南充市中心医院康复科收治的15。例膝骨美节炎患者作 为实验组,同时纳入30例健康志愿者作为对照组。实验组釆用视觉模拟量表(VAS)评价膝关节的疼痛程度,采用膝关 节学会评分系统(KSS)评价膝关节的功能及采用Kellgren Lawrence (KL)分级系统评价膝关节X线严重程度,通过 ELISA试验检测两组膝关节滑液中IL17的水平。采用Spearman相关分析KOA患者关节滑液中IL 17水平与膝关节 疼痛程度、膝关节功能及X线严重程度的相关性。结果 实验组关节滑液中IL17的水平明显高于对照组(P <0. 05). IL 17水平在滕美节炎KL分级之间比较,差异无统计学差异(P>0. 05)。IL 17的水平与膝关节VAS评分呈正相关 (P=0. 914,P<0.01),IL 17的水平与KSS呈负相关(P=—0. 847,P<0. 01), IL 17的水平与KL分级无相关性(r = 0.050,P= 0.545)。结论 IL 17可反应膝骨关节炎患者疼痛程度及功能损伤程度,但不能反映疾病的X线严重程度。 IL 17可作为一个生化指标反应膝关节炎疼痛程度及膝关节功能,临床通过减少关节滑液中IL 17,可能会减轻膝骨关 节炎患者的临床症状。 相似文献
68.
Yi Su Suey S.Y. Yeung Yu-Ming Chen Jason C.S. Leung Timothy C.Y. Kwok 《Journal of bone and mineral research》2022,37(6):1179-1187
Inflammation, an important contributory factor of muscle and bone aging, is potentially modulated by diet. This study examined the associations of dietary inflammatory index (DII) score with musculoskeletal parameters and related disease outcomes in 3995 community-dwelling Chinese men and women aged ≥65 years in Hong Kong. DII score at baseline was estimated from a food frequency questionnaire. Bone mineral density (BMD) and muscle mass estimated by dual-energy X-ray absorptiometry (DXA), hand grip strength, gait speed, and chair stand test were measured at baseline, year 4, and year 14. The associations of DII score with the longitudinal changes of musculoskeletal parameters, and incidence of osteoporosis, sarcopenia, and fractures were examined by using general linear model, multinomial logistic regression model, and Cox proportional hazards regression model, respectively. After multiple adjustments, each tertile increase in DII score in men was associated with 0.37 (95% confidence interval [CI], 0.10–0.64) kg loss in grip strength and 0.02 (95% CI, 0.01–0.03) m/s loss in gait speed over 4 years. In men, the highest tertile of DII was associated with a higher risk of incident fractures, with adjusted and competing death adjusted hazard ratio (HR) (95% CI) of 1.56 (1.14–2.14) and 1.40 (1.02–1.91), respectively. In women, DII score was not significantly associated with any muscle-related outcomes or incidence of fracture, but a significant association between higher DII score and risk of osteoporosis at year 14 was observed, with the highest tertile of DII score having adjusted odds ratio (OR) (95% CI) of 1.90 (1.03–3.52). In conclusion, pro-inflammatory diet consumption promoted loss of muscle strength and physical function, and increased risk of fractures in older Chinese men. Pro-inflammatory diets had no significant association with muscle related outcomes but increased the long-term risk of osteoporosis in older Chinese women. © 2022 American Society for Bone and Mineral Research (ASBMR). 相似文献
69.
70.
OBJECTIVES: To assess the effectiveness and safety of additional bedtime H2‐receptor antagonists (H2RAs) in suppressing nocturnal gastric acid breakthrough (NAB) via a systematic review. METHODS: Eligible trials were identified by searching the Cochrane Central Register of Controlled Trials (CENTRAL) (Cochrane Library Issue 2, 2004), MEDLINE (January 1966–June 2004), EMBASE (January 1980–June 2004) and CINAHL (January 1982–June 2004). Additional hand‐searching was conducted on the proceedings of correlated conferences, eight important Chinese journals and references of all included trials. All randomized controlled trials evaluating H2RAs for the control of NAB were eligible for inclusion. The systematic review was conducted using methods recommended by The Cochrane Collaboration. RESULTS: Only two randomized crossover studies, comprising 32 participants, met the inclusion criteria. Because the design, dosage and duration of the treatments were different between the studies, it was not possible to conduct meta‐analysis. There were no consistent conclusions found between the two included studies in evaluating H2RAs for the control of NAB. CONCLUSIONS: No implications for practice at this stage can be concluded. Appropriately designed large‐scale randomized controlled trials with long‐term follow up are needed to determine the effects of additional bedtime H2RAs in suppressing NAB. 相似文献