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1.
Objective: Lipoprotein lipase (LPL) and hepatic lipase (HL) are essential in hydrolysis of triglyceride‐rich lipoproteins. LPL activity is negatively, whereas HL activity is positively, associated with total body fat. We determined the associations of trunk and leg fat mass with plasma LPL and HL activities in a cross‐sectional study. Research Methods and Procedures: LPL and HL activities were determined in post‐heparin plasma in a sample of 197 men and 209 women, 60 to 87 years of age. A total body DXA scan was performed to determine trunk and leg fat mass. Results: In women, but not in men, trunk fat mass was negatively associated with LPL activity, whereas leg fat mass was positively associated, after mutual adjustment and adjustment for age. Standardized βs (95% confidence interval) for trunk and leg fat mass were ?0.24 (?0.41; ?0.08) and 0.14 (?0.02; 0.31), respectively (interaction by sex, p = 0.03). Larger trunk fat mass was associated with higher HL activity in men [0.48 (0.28; 0.68)] and women [0.40 (0.24; 0.56)]. A negative association of leg fat mass and HL activity was observed in men, although not statistically significant [?0.13 (?0.33; 0.06)], and in women [?0.28 (?0.38; ?0.18)]. Discussion: Abdominal fat is associated with unfavorable and femoral fat with favorable LPL and HL activities in plasma.  相似文献   
2.
《Endocrine practice》2021,27(12):1225-1231
ObjectiveBone health in older individuals with HIV infection has not been well studied. This study aimed to compare bone mineral density (BMD), trabecular bone score (TBS), and bone markers between HIV-infected men and age- and body mass index (BMI)-matched HIV-uninfected men aged ≥60 years. We investigated the associations of risk factors related to fracture with BMD, TBS, and bone markers in HIV-infected men.MethodsThis cross-sectional study included 45 HIV-infected men receiving antiretroviral therapy and 42 HIV-uninfected men. Medical history, BMD and TBS measurements, and laboratory tests related to bone health were assessed in all the participants. HIV-related factors known to be associated with bone loss were assessed in the HIV-infected men.ResultsThe mean BMD, TBS, and osteopenia or osteoporosis prevalence were similar among the cases and controls. The HIV-infected men had significantly higher mean N-terminal propeptide of type 1 procollagen and C-terminal cross-linking telopeptide of type I collagen levels. Stepwise multiple linear regression analysis demonstrated that low BMI (lumbar spine, P = .015; femoral neck, P = .018; and total hip, P = .005), high C-terminal cross-linking telopeptide of type I collagen concentration (total hip, P = .042; and TBS, P = .010), and low vitamin D supplementation (TBS, P = .035) were independently associated with low BMD and TBS.ConclusionIn older HIV-infected men with a low fracture risk, the mean BMD and TBS were similar to those of the age- and BMI-matched controls. The mean bone marker levels were higher in the HIV group. Traditional risk factors for fracture, including low BMI, high C-terminal cross-linking telopeptide of type I collagen level, and low vitamin D supplementation, were significant predictors of low BMD and TBS.  相似文献   
3.
目的:探讨关节镜下逆行交锁髓内钉治疗股骨远端骨折的疗效、特点及其必要性.方法:采用关节镜下逆行交锁髓内钉进行手术治疗36例股骨远端骨折.结果:36例中膝关节内病损17例,经随访6个月至2年,平均10月,膝关节活动度90°~140°,平均125°.骨折愈合时间3~9个月,平均6个月.结论:关节镜引导下逆行交锁髓内钉治疗股骨远端骨折,同时对膝关节内损伤或病变明确诊断并进行相应处理,避免漏诊,手术时间短,最大限度地保留了膝关节的解剖与功能的完整性,对膝关节损伤小,值得推广.  相似文献   
4.
目的:探讨连续股神经阻滞(CFNB)联合帕瑞昔布对全膝关节置换术(TKA)患者术后镇痛效果。方法:选择2015年1月至2016年12月间我院行择期单侧TKA治疗的患者100例,按照随机数字表法分为对照组和研究组,每组各50例。两组患者术后分别接受CFNB和CFNB联合帕瑞昔布镇痛,镇痛时间2 d。观察两组患者术后6 h、12 h、24 h、48 h静息状态和运动状态视觉模拟疼痛评分(VAS)以及术后不良反应发生率。并于术前1 d、术后1 d、2 d、3 d应用美国特种外科医院膝关节评分表(HSS)评定两组患者膝关节功能。结果:术后6 h、12 h、24 h、48 h研究组患者静息状态VAS评分和运动状态VAS评分显著低于对照组患者(P0.05)。两组恶心/呕吐、呼吸抑制、导管相关问题、尿潴留发生率比较无统计学差异(P0.05)。两组患者术前1d HSS评分比较无统计学差异(P0.05),术后1 d、术后2 d、术后3 d两组患者HSS评分均较术前1 d显著升高,且研究组患者HSS评分显著高于对照组(P0.05)。结论:CFNB联合帕瑞昔布具有镇痛效果好、安全可靠的优点,应用TKA术后镇痛有利于患者早期进行膝关节功能锻炼,值得临床推广。  相似文献   
5.
Simple repetitive DNA sequences from primates: Compilation and analysis   总被引:25,自引:0,他引:25  
Simple repeats composed of tandemly repeated units 1–6 nucleotides (nt) long have been extracted from a selected set of primate genomic DNA sequences. Of the 501 theoretically possible, different types of repeats only 67 were present in the analyzed database in at least two different size ranges over 12 nt. They include all simple repeats known to be polymorphic in the primate genome. A list of moderately expanding and nonexpanding oligonucleotide patterns has also been included. Furthermore, we have compiled statistical data with emphasis on the overall variability of the most abundant 67 types of repeats. We have demonstrated that the expandability of at least some simple repeats may be affected by the overall base composition and by flanking sequences. In particular, the occurrence of tandemly repeated CAG and GCC triplets in exons positively correlates with their G+C content. We also noted that in the vicinity of Alu sequences tetrameric repeats are more abundant than in the total genomic DNA. This paper can be used as a comprehensive guide in identification of the most abundant and potentially polymorphic simple repeats. It is also of broader significance as a step toward understanding the contribution of flanking sequences and the overall sequence composition to variability of simple repeats. Correspondence to: J. Jurka  相似文献   
6.
目的:研究人工髋关节置换术中股骨假体周围骨折的影响因素及其相关性,为人工髋关节置换术中股骨假体周围骨折的预防和诊治提供科学依据。方法:选取本院2012年11月至2013年9月施行髋关节置换手术的患者780例,搜集各研究对象的一般资料(年龄、性别等)以及随访观察其髋关节置换手术后股骨假体周围骨折的发生情况,把股骨假体周围骨折的发生情况与性别、年龄、固定类型等因素进行Logistic回归分析。结果:780例施行髋关节置换手术的患者中,有52例患者术后出现股骨假体周围骨折,总发生率为6.7%;其中A型31例,B型18例(B1型6例,B2型7例,B3型5例),C型3例。女性的发生率(8.5%)高于男性(4.7%),老年患者中股骨假体周围骨折的发生率最高(10.1%),生物型假体固定者的发生率(8.7%)高于骨水泥型假体固定者(3.8%),人工髋关节翻修术中股骨假体周围骨折的发生率最高(11.4%),股骨假体周围骨折发生的危险因素为女性、高龄、使用生物型假体固定,OR值分别为5.301、3.675和2.336。结论:人工髋关节置换术中的危险因素为女性、高龄、使用生物型假体固定,临床医生应在术前对行人工髋关节置换术手术者进行充分的评估,制定合理的手术方案及选择合适的固定方式。  相似文献   
7.
目的:比较连续股神经阻滞(CFNB)与静脉自控镇痛(PCIA)在全膝关节置换术中的应用效果及对患者凝血功能的影响。方法:选取2014年1月至2015年12月间我院行单侧全膝关节置换术的患者80例,按照随机数字表法分为CFNB组和PCIA组,每组各40例,两组患者分别接受CFNB和PCIA治疗。观察两组患者术后6 h、12 h、24 h、48 h视觉模拟疼痛评分(VAS),两组患者分别于麻醉前(T1)、术毕(T2)、术后1 d(T3)、术后2 d(T4)进行血栓弹力图检查,观察两组凝血功能变化。并于术后随访1年,比较两组患者膝关节功能。结果:术后6 h、12 h、24 h、48 h CFNB组患者VAS评分显著低于PCIA组患者(P0.05)。T2、T3、T4时点CFNB组患者凝血反应时间(R)、血凝块形成时间(K)较T1升高,血凝块聚合形成速率(α角)、血凝块最大振幅(MA)较T1降低,PCIA组患者R、K较T1降低,α角、MA较T1升高,T2、T3、T4时点CFNB组患者R、K高于PCIA组患者,α角、MA低于PCIA组患者,差异均有统计学意义(P0.05)。两组患者术后均完成1年的随访,两组患者KSS评分、膝关节最大屈曲度、膝关节最大伸直度比较无统计学差异(P0.05)。结论:CFNB对于全膝关节置换术术后患者镇痛效果优于PCIA,有利于改善患者凝血功能,不影响术后患者膝关节功能的恢复。  相似文献   
8.
The therapeutic effects of electric and magnetic fields have been studied largely for their promotion of connective tissue repair. The most widely studied application concerns bone repair and deals with acceleration of the healing of fresh fractures, delayed and non-unions, incorporation of bone grafts, osteoporosis, and osteonecrosis. More recently the effects of these fields upon the repair of cartilage and soft fibrous tissues have been described. In all these experimental systems and clinical applications an acceleration of extracellular matrix synthesis and tissue healing has been observed. A degree of specificity, in terms of the parameters of applied energy and biological response, is hypothesized.  相似文献   
9.
The stabilization of the human standing posture was originally attributed to the stiffness of the ankle muscles but direct measurements of the ankle stiffness ruled out this hypothesis, leaving open the possibility for a feedback stabilization strategy driven by proprioceptive signals. This solution, however, could be implemented with two different kinds of control mechanisms, namely continuous or intermittent feedback. The debate is now settled and the latter solution seems to be the most plausible one. Moreover, stabilization of unstable dynamics is not limited to bipedal standing. Indeed many manipulation tasks can be described in the same framework and thus a very general protocol for addressing this kind of problems is the use of haptic virtual reality where instability is generated by some kind of divergent or saddle-like force field. Several studies demonstrated that human subjects can choose to adopt a stiffness or feedback strategy as a combination of biomechanical and task constraints and can learn to switch from one strategy to the other if it is feasible or to use one or the other is infeasible. Understanding such mechanisms is relevant, for example, for the design of novel ergonomic man-machine interfaces in difficult, unstable tasks.  相似文献   
10.
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