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111.
研究生一年级学生运动等级与其健康状况的相关性   总被引:2,自引:0,他引:2  
目的:调查研究生一年级学生的体育锻炼和健康状况,并分析其相关性。方法:调查于2005-09/10完成。选取西南大学和重庆大学2005级研究生一年级学生作为调查对象,共发放问卷190份,男90份,女100份。进行问卷调查,当场收回问卷。问卷内容:①自测健康评定量表:由48个条目构成,1~17为自测生理健康评定子量表(170~0分),19~34为自测心理健康子量表(150~0分),35~47为自测社会健康子量表(120~0分),分数越高代表越健康。②体育活动等级量表:主要调查调查对象上1个月参加体育锻炼的运动量,运动量=强度×时间×频率,强度与频率从1~5等级分别计1~5分,时间从1~5等级分别计0~4分,故运动量最高分为100分,最低分为0分。结果:有效回收176份问卷进入结果分析。①不同性别调查对象在运动等级上的分布情况:研究生一年级男女新生的运动量水平都偏低(男生:31.80±23.19,女生:15.57±15.39),且性别对运动量有显著的主效应(P<0.01),女生在运动量上的得分显著偏低。②调查对象健康状况各维度与运动量的相关性:运动量与总体健康、生理健康、心理健康和社会健康都存在显著相关性(r=0.150~0.238,P<0.05~0.01),生理健康对运动量有显著的预测作用(P<0.05)。③不同运动量等级调查对象的健康量表得分:运动等级对生理健康有显著的主效应(P<0.01),随着运动量的增加,研究生一年级学生的生理健康水平不断提高。结论:研究生一年级学生的体育锻炼运动量与健康水平存在着明显的正相关,随着运动量的增加,生理健康、心理健康及社会健康水平均不断增加。  相似文献   
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113.
This study developed a predictive model for fires and burns among parents and children in Jefferson County, Kentucky. Eight risk factors for pediatric burns with census tract level data available were identified. Risk factors were synthesized to develop a cartographic model with risk levels low, medium, high, and severe. Validation was performed with fire dispatch data. At-risk areas were concentrated in the county’s northwest. Risk was correlated with fire incidence rate (ρ = 0.67, p < 0.001). Significant risk factors were race (β = 0.54, p < 0.001), education (β = 0.38, p < 0.001), and year home built (β = ?0.17, p = 0.005). Cartographic modeling is a underutilized tool to identify at-risk areas.  相似文献   
114.
We have developed a murine model of wasting by injecting intracerebrally cells which continuously secrete h-cachectin/TNF (CHO-TNF) to: (a) determine the effects of cachectin/TNF produced continuously in the central nervous system (CNS), and (b) compare the metabolic effects of cachectin/TNF-secreting tumor in the brain to the cachexia caused by CHO-TNF tumor in peripheral tissue (IM). Intracerebral CHO-TNF tumors produced increased serum h-cachectin/TNF levels with lethal hypophagia and weight loss (mean survival time of 11 d); these changes were not observed in association with nonsecretory control brain tumors. The metabolic consequences of intracerebral cachectin/TNF production were indistinguishable from acute, lethal starvation: whole-body lipid content was decreased significantly but protein was conserved. Although intramuscular cachectin/TNF-secreting tumors caused similar increases of serum h-cachectin/TNF levels, profound anorexia did not develop; wasting developed after a longer period of tumor burden (50 d) with classical signs of cachexia (i.e., anemia and depletion of both protein and lipid). These studies provide a reproducible animal model of site-specific cytokine production and suggest that, regardless of serum levels, cachectin/TNF produced locally in brain influences both the rate of development of wasting and its net metabolic effects.  相似文献   
115.
Antisense hTERT inhibits thyroid cancer cell growth   总被引:10,自引:0,他引:10  
Activation of telomerase represents an early step in carcinogenesis. Increased telomerase expression in malignant thyroid tumors suggests that inactivation of telomerase may represent a potential chemotherapeutic target. The purpose of this study was to inhibit the protein component of telomerase, hTERT, in a human thyroid cancer cell line in vitro and in vivo using an antisense strategy. A 235-bp fragment of hTERT cDNA was subcloned, and sense and antisense hTERT expression vectors were constructed. These vectors were transfected into a human thyroid carcinoma cell line (FRO). Tumorigenic potential was determined by cellular growth assay, rate of apoptosis, anchorage-independent growth, and tumor growth in a nude mouse model. Significant down-regulation of hTERT expression was seen in the antisense transfected cells, compared with control and those transfected with the sense vector. A decrease in telomerase activity by TRAP assay was observed in the antisense hTERT cells but not in cells transfected with the sense hTERT construct. Inhibition of cell growth was observed after approximately 20 population doublings in the antisense-hTERT clones and was associated with an increase in the rate of apoptosis and a change in cellular morphology. Moreover, anchorage-independent growth was reduced in vitro, and tumor growth rate was diminished in vivo in the antisense hTERT clones. Inhibition of telomerase activity with antisense hTERT in human thyroid cancer cells is achievable and may represent a novel target to inhibit tumor growth.  相似文献   
116.
A multilaboratory study was conducted to develop a system for standardizing alanine aminotransferase (ALT) acceptability criteria ("cutoffs") for donated blood. Without standardized cutoffs, each laboratory must develop its own cutoff, and this may not make optimal use of ALT testing to reduce transmission of non-A, non-B hepatitis (NANB). Defining an ALT acceptability criterion in absolute terms is necessary because relative cutoffs based on local donor populations may be affected by the prevalence of NANB in each community. This study involved 16 laboratories using 23 different analytic systems. The ALT results of the analysis of a plasma reference sample could be used to translate mathematically a single, absolute cutoff to units applicable to each analytic system. The distribution of ALT results in 1.4 million donations from across the country was established; basing the cutoff on this sample avoids the problems inherent in using a local donor base to establish a cutoff. We propose the implementation of a system to standardize ALT acceptability criteria to an activity level defined by analysis of a nationwide donor sample.  相似文献   
117.
Concept mapping, a learning strategy used to understand key concepts and relationships between concepts, has been suggested as a method to plan and evaluate nursing care. The purpose of this study was to empirically test the effectiveness of concept mapping for student learning and the students' satisfaction with the strategy. A quasi-experimental pre- and posttest design was used to examine the content of concept maps of care plans constructed by junior-level baccalaureate students (n = 23) at the beginning and end of a community-based mental health course. Additionally, students completed a questionnaire to self-evaluate their learning and report their satisfaction with concept mapping. Findings indicated that concept mapping significantly improved students' abilities to see patterns and relationships to plan and evaluate nursing care, and most students (21/23) expressed satisfaction in using the strategy. This study supported concept mapping as an additional learning strategy and has extended knowledge in community-based nursing education.  相似文献   
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119.
Maternal obesity increases the risk of numerous complications of pregnancy, labor, and birth for both mother and neonate, including diabetes and hypertensive disorders. As more women enter pregnancy with a body mass index (BMI) indicative of overweight or obesity, providers of obstetric care should be aware of the implications of this increased BMI on perinatal outcomes as well as become familiar with management options.  相似文献   
120.
PURPOSE: To evaluate the dose from the computed tomographic (CT) portion of positron emission tomography (PET)/CT to determine minimum CT acquisition parameters that provide adequate attenuation correction. MATERIALS AND METHODS: Measurements were made with a PET/CT scanner or a PET scanner, five anthropomorphic phantoms (newborn to medium adult), and an ionization chamber. The CT dose was evaluated for acquisition parameters (10, 20, 40, 80, 160 mA; 80, 100, 120, 140 kVp; 0.5 and 0.8 second per rotation; 1.5:1 pitch). Thermoluminescent dosimetry was used to evaluate the germanium 68/gallium 68 rod sources. A phantom study was performed to evaluate CT image noise and the adequacy of PET attenuation correction as a function of CT acquisition parameters and patient size. RESULTS: The volumetric anthropomorphic CT dose index varied by two orders of magnitude for each phantom over the range of acquisition parameters (0.30 and 21.0 mGy for a 10-year-old with 80 kVp, 10 mAs, and 0.8 second and with 140 kVp, 160 mAs, and 0.8 second, respectively). The volumetric anthropomorphic CT dose index for newborn phantoms was twice that for adult phantoms acquired similarly. The rod source dose was 0.03 mGy (3-minute scan). Although CT noise varied substantially among acquisition parameters, its contribution to PET noise was minimal and yielded only a 2% variation in PET noise. In a pediatric phantom, PET images generated by using CT performed with 80 kVp and 5 mAs for attenuation correction were visually indistinguishable from those generated by using CT performed with 140 kVp and 128 mAs. With very-low-dose CT (80 kVp, 5 mAs) for the adult phantom, undercorrection of the PET data resulted. CONCLUSION: For pediatric patients, adequate attenuation correction can be obtained with very-low-dose CT (80 kVp, 5 mAs, 1.5:1 pitch), and such correction leads to a 100-fold dose reduction relative to diagnostic CT. For adults undergoing CT with 5 mAs and 1.5:1 pitch, the tube voltage needs to be increased to 120 kVp to prevent undercorrection.  相似文献   
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