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101.
目的:为健美运动员补充蛋白质提供科学的饮食方法,以期增加其肌肉体积,达到发展肌肉力量的同时健美体形,对健美运动员补充蛋白质研究作一综述。资料来源:应用计算机检索http://www.chkd.cnki.net/index.htm/,http://www.highwire.org/1994/2007有关补充蛋白质和增加肌肉力量相关的论文,英文检索词为"protein,strength",并限定语种为English;中文检索词为"补充蛋白质,肌肉力量",并限定语种为中文;另外手工查找与补充蛋白质和增加肌肉力量有关的资料和书籍。资料选择:对资料进行初审,选取与补充蛋白质和增加肌肉力量相关的文献,所选择的文献为研究原著,排除重复研究。资料提炼:共收集到200篇补充蛋白质和增加肌肉力量的文献,在选择、分析的基础上,排除重复或类似研究,最终提炼出29篇文献进行分类整理用于综述。资料综合:①运动与蛋白质关系非常密切。当运动强度加大时,使运动员尿氮排出增加并出现尿负氮平衡,因此要适当的补充蛋白质。②补充蛋白质,可以增加肌肉生理横断面,肌纤维增粗,增加肌红蛋白、血红蛋白、酶和蛋白类激素的合成,有利于增加肌肉力量。结论:健美运动员高强度训练期间,为了恢复运动中的消耗、修复损伤的组织、提高健美训练效果,应给予高蛋白类膳食。同时,还需要保持均衡膳食,适当增加矿物质和维他命以及其他营养补剂的补充。  相似文献   
102.
Bruce J  Drury N  Poobalan AS  Jeffrey RR  Smith WC  Chambers WA 《Pain》2003,104(1-2):265-273
Chronic pain after surgery is recognised as an important post-operative complication; recent studies have shown up to 30% of patients reporting persistent pain following mastectomy and inguinal hernia repair. No large-scale studies have investigated the epidemiology of chronic pain at two operative sites following coronary artery bypass grafting (CABG). This paper reports the follow-up of a cohort of 1348 patients who underwent cardiac surgery between 1996 and 2000 at one cardiothoracic unit in northeast Scotland. Chronic pain was defined as pain in the location of surgery, different from that suffered pre-operatively, arising post-operatively and persisting beyond 3 months. The survey questionnaire consisted of the short-form-36 (SF-36), Rose angina questionnaire, McGill pain questionnaire and the University of California and San Francisco (UCSF) pain service questionnaire. Of the 1080 responders, 130 reported chronic chest pain, 100 chronic post-saphenectomy pain and 194 reported pain at both surgical sites. The cumulative prevalence of post-cardiac surgery pain was 39.3% (CI(95) 36.4-42.2%) and mean time of 28 months since surgery (SD 15.3 months). Patients who reported pain at both sites had lower quality of life scores across all eight health domains compared to patients with pain at one site only and those who were pain-free. Prevalence of chronic pain decreased with age, from 55% in those aged under 60 years to 34% in patients over 70 years. Patients with pre-operative angina and those who were overweight or obese (BMI>/=25) at the time of surgery were more likely to report chronic pain. Chronic pain following median sternotomy and saphenous vein harvesting is more common than hitherto reported and that patients undergoing CABG should be warned of this possibility.  相似文献   
103.
新复合纤维蛋白胶可注射性磷酸钙人工骨的理学特性   总被引:2,自引:0,他引:2  
目的:检测纤维蛋白胶复合β-磷酸三钙/磷酸二氢钙复合人工骨材料的物理学性能,评价纤维蛋白胶对β-磷酸三钙/磷酸二氢钙骨水泥性能的影响,以及其作为注射型复合人工骨用于修复骨缺损的可行性。方法:实验于2006-12/2007-06在南方医科大学珠江医院中心实验室和华南理工大学生物材料实验室完成。①材料:β-磷酸三钙由上海瑞邦生物材料有限公司提供,磷酸二氢钙为东泰化工赠,纤维蛋白胶购自广州倍绣生物技术有限公司。②复合材料制备:将β-磷酸三钙/磷酸二氢钙骨水泥按3∶1的比例充分混合后,与纤维蛋白胶按凝固后的体积2∶1体积比混合,制成复合人工骨材料。③观察指标:测定复合材料的凝固时间,抗压强度,抗稀散性能,并用扫描电镜观察其煅烧前后的显微结构特征,以未加纤维蛋白胶的磷酸钙水泥为对照(CPC组)。结果:复合人工骨材料的平均初凝时间长于CPC组(P<0.004),终凝时间在初凝时间后2~4 min;复合材料的抗压强度为(14.72±1.81)MPa。复合材料较CPC组有良好的抗稀散性能,扫描电镜发现,纤维蛋白胶贯穿于磷酸钙水泥晶体间,并将磷酸钙水泥晶体紧密连接。煅烧后复合材料的孔径有增大,空隙率为57.28%,并且微孔之间有空隙互相贯通。结论:该骨水泥复合材料凝固时间符合临床操作的需要;抗压强度达到松质骨强度的要求;煅烧后磷酸钙水泥的空隙率明显提高,有利于材料的降解。  相似文献   
104.
目的:缝隙连接蛋白43对维持心肌细胞的连接通讯功能、电信号传导和正常的节律性收缩起重要作用,其表达和分布的异常是多种室性心律失常的解剖学基础,建立小型猪急性心肌梗死模型.观察自体骨髓间充质干细胞移植后室性心动过速的发生及心肌缝隙连接蛋白43的表达方法:实验于2006-01/2007-01在河北省人民医院导管室完成。①材料:选取8~12月龄小型猪22头,由河北医科大学实验动物中心提供,体质量20~30 kg,随机数字表法分为细胞移植组12头、模型对照组10头.实验过程中对动物的处置符合动物伦理学际准②实验方法:无菌条件下抽取猪双侧股骨骨髓20 mL,percoll法 贴壁法分离培养骨髓间充质干细胞,待细胞生长达75%融合时用胰酶消化传代。将传至第2代细胞加入终浓度为10μmol/L的5-氮胞苷进行诱导,用胶体金标记12 h后继续培养20 d用于移植:两组小型猪均采用球囊堵闭法建立急性心肌梗死模型.心电图监测示相关至少2个导联ST段抬高大于0.2 mV、术后血肌钙蛋白和肌酸磷酸激酶同工酶升高超过正常的两倍为建模成功标准:细胞移植组于造模成功后经OTW球囊于第一对角支远端1 cm处再次阻断血流,注入经胶体金标记的10×10~7个骨髓间充质干细胞。③实验评估:于细胞移植后2 h及4周行电生理程序刺激.观察室性心动过速的发生情况。末次电生理检查后、采用免疫组化染色法检测心肌缝隙连接蛋白43的表达.计算其积分吸光度值。结果:①模型建立指标检测:与术前比较.造模后所有小型猪血肌钙蛋白含量和肌酸磷酸激酶同工酶活性均增高,峰值浓度分别为(21.3±3.6)μg/L和(178.3×41.4)IU/L,术中心电图ST段平均抬高(10.67±1.43)mm.证明急性心肌梗死模型成功建立。②骨髓间充质干细胞移植后室性心动过速的发生情况:与模型对照组诱发出室性心动过速的动物数量比较,术后2 h细胞移植组无明显变化(X~2=0.201,P=0.650),术后4周细胞移植组明显降低(X~2=4.455.P=0.035)。②骨髓间充质干细胞移植后梗死心肌缝隙连接蛋白43的表达:术后4周移植到梗死心肌的骨髓间充质干细胞与宿主心肌生长为一体,移植部位颜色变黑,苏木精-伊红染色示移植细胞的胞浆呈紫红色。细胞移植组心肌梗死区缝隙连接蛋白43积分吸光度值明显高于模型对照组(t=16,82.P=0.00),细胞移植组中未发生室性心动过速小型猪的梗死心肌缝隙连接蛋白43的表达明显高于发生室性心动过速小型猪(t=5.06,P=0.00)。结论:自体骨髓间充质干细胞移植可促进急性心肌梗死猪心肌缝隙连接蛋白43的表达,其表达程度可能与急性心肌梗死室性心动过速的发生有关。  相似文献   
105.
The uptake of evidence into practice may be impeded or facilitated by individual and organizational factors within the local context. This study investigated Nurse Managers of New South Wales, Australia, stroke units (n = 19) in their views on: leadership ability (measured by the Leadership Practices Inventory), organizational learning (measured by the Organizational Learning Survey), attitudes and beliefs towards evidence‐based practice (EBP) and readiness for change. Overall Nurse Managers reported high‐level leadership skills and a culture of learning. Nurse Managers' attitude towards EBP was positive, although nursing colleague's attitudes were perceived as less positive. Nurse Managers agreed that implementing evidence in practice places additional demands on staff; and almost half (n = 9, 47%) reported that resources were not available for evidence implementation. The findings indicate that key persons responsible for evidence implementation are not allocated sufficient time to coordinate and implement guidelines into practice. The findings suggest that barriers to evidence uptake, including insufficient resources and time constraints, identified by Nurse Managers in this study are not likely to be unique to stroke units. Furthermore, Nurse Managers may be unable to address these organizational barriers (i.e. lack of resources) and thus provide all the components necessary to implement EBP.  相似文献   
106.
107.
Drury J A, Nik H, van Oppenraaij R H F, Tang A‐W, Turner M A & Quenby S
(2011 Histopathology  59 , 1156–1162
Endometrial cell counts in recurrent miscarriage: a comparison of counting methods Aims: Studies of uterine natural killer (uNK) cells require reliable measurements of uNK cell density among diverse endometrial tissue. The aim of this study was to compare cell counting manually with two computer‐aided methods based on a public domain software package, ImageJ. Methods and results: Immunohistochemistry (IHC) of CD56+ uNK cells was performed on endometrium from recurrent miscarriage patients. Numbers of stromal cells per high‐power field (HPF) were counted by two observers using: (i) manual tally counter and graticule; (ii) ImageJ ‘point picker’ tool; and (iii) ImageJ ‘particle analysis’ tool. Coefficients of variation (CV) and Bland–Altman plots were used to evaluate interobserver differences. Evaluation of %uNK using ImageJ particle analysis for stromal cell counts and point picker tool for uNK counts was undertaken. Point picker and particle analysis were significantly better than manual counting [interobserver CVs mean (standard deviation) 6.1% (3.3%); 4.7% (3.9%), 8.2% (6.5%), respectively]. Mean inter‐ and intra‐observer CVs for %uNK were 10.3% (6.6%), 8.5% (4.9%) and 6.8% (4.3%), respectively. Bland–Altman analysis revealed no systematic differences in cell counts with the number of cells in the image for each method. Conclusions: Compared to manual cell counting, computer‐aided image analysis yields more reproducible results for the assessment of uNK cells density using IHC.  相似文献   
108.
109.
Congenital defects of the pericardium are rare, but when they are reported they are frequently associated with other cardiac lesions. We describe a case of partial pericardial defect found incidentally at surgery for closure of an ostium primum atrial septal defect. Proposed mechanisms of pericardial defect development are discussed and we suggest that associations with congenital and acquired heart disease are mostly circumstantial.  相似文献   
110.
Platelets have a central role in the development of arterial thrombosis and subsequent cardiovascular events. An appreciation of this complex process has made antiplatelet therapy the cornerstone of cardiovascular disease management. However, numerous patients will experience a recurrent atherothrombotic vascular event despite adequate antiplatelet therapy. Individual differences in the rate of platelet activation and reactivity markedly influence normal hemostasis and the pathological outcome of thrombosis. Such an individual variability is largely determined by environmental and genetic factors. These are known to either hamper platelets' response to agonists, and thereby mimic the pharmacological modulation of platelet function or mask therapy effect and sensitize platelets. In this article, we reviewed the antiplatelet mechanisms of aspirin and clopidogrel and the possible role of different polymorphisms, which may affect the efficacy of antiplatelet therapy. Heterogeneity in the way patients respond to aspirin and clopidogrel may in part reflect variation in cyclooxygenase (COX)-1, COX-2, glycoprotein (GP) Ib alpha, GP Ia/IIa, GP IIb/IIIa, UGT1A6*2, P2Y1, P2Y12, CYP2C9, CYP3A4 and CYP3A5 genotypes.  相似文献   
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