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131.
132.
"技术的社会形成"(SST)理论主要是通过大量的案例来分析具体的技术或技术制品在社会因素作用下的形成过程.考察作为中国原创技术的杂交水稻技术发明的经济、政治、文化等社会动力,理解中国的技术国情对中国本土技术形成的正向作用.  相似文献   
133.
Cardiovascular autonomic neuropathy (CAN) is one of the most clinically significant complications of diabetes mellitus. Even though many ethological factors have been attributed for the pathogenesis of this disease no attempts were made to correlate DNA damage as a causative factor. Hence the present study was undertaken to asses the extent of somatic DNA damages by cytokinesis-block micronuclei assay (CBMN). An attempt is also being made to correlate the habits and/or risk factors and socioeconomic status with CAN. The CBMN frequency of 46 patients suffering from autonomic neuropathy was compared with that of 25 healthy age and sex matched controls. All the subjects were suffering from type 2 diabetes for at least 8 years and have varying degrees of coronary artery diseases. The mean CBMN frequency of the patients was statistically higher than that of the healthy control subjects (P < 0.05). The CBMN frequency was found to be significantly altered in CAN patients who where physical inactivity and smoking. A significant correlation could also be observed between CAN and smoking, diabetes mellitus, hypertension, dyslipidemia, abdominal obesity, and physical activity.  相似文献   
134.
运动性猝死、过劳死41例统计分析及对策研究   总被引:1,自引:0,他引:1  
近年来,在体育运动、劳动、工作和生活等各种场合、连续发生运动性猝死和过劳死的不幸事件,引起社会各界惊恐及关注。结合41例运动性猝死和过劳死的病例资料统计分析,论述运动性猝死和过劳死的定义、流行病学、病因、诱因、预防和急救,有针对性对此问题加以研究综述。  相似文献   
135.
在网球比赛中取胜,需要有天赋的运动员、优秀的教练员、适合的器材,以及对这个运动项目相关的体育科学的有关方面的理解。本文从体育科学和运动医学角度阐述了生物力学在运动员发展中的作用。生物力学在运动员发展中起着关键性的作用,因为所有的击球都具有一个基本的力学结构,运动损伤都是由于力学因素引起的。这篇发表在《英国运动医学杂志》上的研究综述从不同角度论述了网球运动中的生物力学问题。文章全面涵盖了网球运动所涉及的生物力学一般理论、网球运动技术和网球运动损伤生物力学。文章作者Bruce Elliott教授长期从事网球等运动的生物力学研究,是国际著名的运动生物力学专家,曾为国际运动生物力学学会(International Society of Biomechanics in Sports,ISBS)主席。  相似文献   
136.
The aims of this study were: (i) to determine kinematic, kinetic, and electromyographic characteristics of Junzuki karate punch in professional karate athletes; (ii) to identify biomechanical parameters that correlate with punch force and lead to a higher punching performance; (iii) to verify the presence of muscle co-activation in the upper limb, trunk, and lower limb muscles. Data were collected from nine experienced karatekas from the Accademia Italiana Karate e Arti Marziali during the execution of the specific punch. Mean punch forces (181.2?N) delivered to the target, the range of motion of both right and left knees (1.13 and 0.82?rad) and right elbow (1.49?rad) joints, and the angles at impact (knee: 0.81 and 0.91?rad; elbow: 1.19?rad) in the sagittal plane were computed. Furthermore, the trunk rotational angular acceleration (63.1?rad?s?2), force related to the lower limbs (550.2 and 425.1?N), and co-activation index for the upper limb (36.1% and 34.7%), trunk (24.5% and 16%), and lower limbs (16.0% and 16.1%) muscles were evaluated bilaterally. Significant positive correlations were found between the punch force and both right and left knee flexion at the instant of impact and right and left leg force. Significant negative correlation was found between the punch force and maximum trunk angular acceleration. Significant differences (p?=?.03) in the co-activation index among the upper limb, trunk, and lower limbs muscles highlighted a rostro-caudal gradient on both body sides. This research could be of use to performers and coaches when considering training preparations.  相似文献   
137.
The objective of the present study was to investigate the antioxidant status and the extent of oxidative DNA damage in lymphocytes and their relation with essential hypertension (EHT). A total of 100 South Indian subjects aged 30–65 were included for the study. Of these 50 were normotensive controls (group-1) with blood pressure ≥120/80 mm Hg, 50 were newly diagnosed (group-2) and were not on any antihypertensive drugs, but had systolic blood pressure ranging between 140 and 160 mmHg and diastolic blood pressure 95–100 mmHg and 50 newly diagnosed essential hypertensive patients underwent drug therapy for 1 year was considered as group-3. Enzymatic and non-enzymatic antioxidants significantly decreased and lymphocyte DNA damage was significantly increased in newly diagnosed hypertensive patients compared with control group. The major decrease in DNA damage and significant improvement in enzymatic and non-enzymatic antioxidants were observed after 1 year of antihypertensive therapy in treated group compared with newly diagnosed hypertensive patients. Total antioxidant status and lymphocyte DNA damage showed a strong negative correlation in all the three groups. Essential hypertension associated with oxidative stress which in turn causes genotoxic susceptibility to variety of disease including cancer. In the absence of DNA repair process and DNA checkpoint mechanisms, the genomic integrity is susceptible to extensive damage. In our study, increased oxidative DNA damage and decreased antioxidant levels were frequently observed in the newly diagnosed essential hypertensive patients, suggesting that oxidative stress is important in the pathogenesis of EHT. Therefore, the present study has additional clinical implication. Further investigations with large number of patients along with antioxidant supplement are highly warranted.  相似文献   
138.
A rapid and inexpensive plasma glucose estimation by two-point kinetic method based on glucose oxidase and peroxidase enzymes has been developed it takes only 11/2 minutes of time and validity of the method has been discussed.  相似文献   
139.
Development and evaluation of immunoassay for zeranol in bovine urine   总被引:1,自引:0,他引:1  
A high affinity polyclonal antibody-based enzyme linked immunosorbent assay (ELISA) was developed for the quantification of zeranol in bovine urine. On the basis of urine matrix studies, the optimized dilution factors producing insignificant matrix interference were selected as 1:5 in pretreatment. In the improved ELISA, the linear response range was between 0.02 and 1 μg/ml, and the detection limit was 0.02 μg/ml for the assay. The overall recoveries and the coefficients of variation (CVs) were in the range of 82%-127% and 3.5%-8.8%, respectively. Thirty-six bovine urine samples spiked with zeranol (ranging from 0.2 to 10 μg/ml) were detected by the ELISA and liquid chromatography (LC) method, and good correlations were obtained between the two methods (R^2=0.9643). We conclude that this improved ELISA is suitable tool for a mass zeranol screening and can be an altemative for the conventional LC method for zeranol in bovine urine.  相似文献   
140.
在日益复杂化的市场竞争环境中,影响企业经营成果水平的因素越来越多。使用何种方法对企业经营成果进行测定才更为合理准确,一直是广大学者和企业战略家们探讨的热门话题。本文分析了传统企业成果测定方法的局限性,从战略角度出发,以企业竞争优势为中心,介绍了3M经营成果测定法;剖析了其与企业竞争优势之间的关系,并设定了3M经营成果测定模型。希望能够为以Concordance Process理论为代表的关于企业竞争优势的各种研究提供一种准确可行的成果测定方法,使今后的实证研究更加严谨科学。  相似文献   
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