胸部气道的CT研究

作者采用自己设计的两种扫描方法与常规扫描方法对照对６７例患者的正常气道的ＣＴ表现进行分析，比较不同扫描方法在显示气道方面的优劣。结果显示：常规ＣＴ扫描方法能显示大部分支气管分枝，最远可分辨亚段支气管，但对右侧Ｂ４、Ｂ５，左侧Ｂ２、ＬＢ、Ｂ４、Ｂ５及两侧Ｂ７、Ｂ８显示差；扫描架向头侧倾斜２５°能明显改善右侧Ｂ４、Ｂ５，左侧ＬＢ、Ｂ４、Ｂ５的显示情况。     

有机药物化学中不对称合成手性产率及其随温度变化规律的研究

本文首次用分子力学计算产物或过渡态分子内张力能来估算热力学或动力学,控制不对称合成反应生成的立体异构体的相对比例,并从热力学上推导了这一比例随温度变化公式,而且从实验上得到证明,在有机或药物化学最富有挑战性的领域——不对称合成中具有重要的理论和实际意义。     

Nutrition, Exercise, and Healthy Aging

Advancing age is associated with a remarkable number of changes in body composition, including reduction in lean body mass and increase in body fat, which have been well documented. Decreased lean body mass occurs primarily as a result of losses in skeletal muscle mass. This age-related loss in muscle mass has been termed “sarcopenia”. Loss in muscle mass accounts for the age-associated decreases in basal metabolic rate, muscle strength, and activity levels, which, in turn are the cause of the decreased energy requirements of the elderly. In sedentary persons, the main determinant of energy expenditure is fat-free mass, which declines by about 15% between the third and eighth decade of life. It also appears that declining energy needs are not matched by an appropriate decline in energy intake, with the ultimate result being increased body fat content. Increased body fatness and increased abdominal obesity are thought to be directly linked to the greatly increased incidence of non-insulin-dependent diabetes mellitus among the elderly. In this review we will discuss the extent to which regularly performed exercise can affect nutrition needs and functional capacity in the elderly. We will also discuss a variety of concerns when prescribing exercise in the elderly, such as planning for a wide variability in functional status, medical status, and training intensity and duration. Finally, we will attempt to provide some basic guidelines for beginning an exercise program for older men and women and establishing community-based programs.     

Body Fat Percentage of Children Varies According to Their Diet Composition

Objective To ascertain the association between diet composition and body fat percentage in 9- and 10-year-old children. Also, to examine the influence of gender, total energy intake, fitness, physical activity, and parental body mass on the relationship between diet composition and adiposity.Design Diet composition was assessed using the National Cancer Institute food frequency questionnaire, and adiposity was measured using the average of results determined using two skinfold equations. Fitness levels and physical activity were ascertained using the 1-mile run/walk test and a self-report 15-item scale, respectively.Subjects A sample of 262 children (162 boys and 100 girls, mean age=9.8±0.5 years) participated.Statistical analysis Regression analysis was used to determine the extent to which diet composition contributed to adiposity without statistical control for any potentially confounding variables. Partial correlations were calculated to assess the relationship between macronutrient intake and adiposity after potential confounders (gender, total energy intake, physical fitness, and parental body mass) were controlled statistically.Results Energy intake was positively related to adiposity. Fat intake, calculated as a percentage of total energy, was also positively related to adiposity, before and after control for potential confounding variables. Percentage of energy derived from carbohydrate was inversely related to adiposity, before and after controlling for potential confounders.Applications These findings indicate that the macronutrient intake of children, particularly dietary fat and carbohydrate intake, may play a role in adiposity, independent of the influence of total energy intake, gender, physical fitness, and parental body mass index.