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161.
社会工作作为一种综合性专业性的助人活动,其理念应用于医疗实践能以专业的价值观和科学的方法,通过提供各种辅导和服务,协助患者及其家属与医方进行有效的沟通,促使医疗技术和服务更人性化地满足患者的需要,从而构建和谐的医患关系。在此过程中,社会工作者针对医患关系发展的不同阶段,分别拓展出不同的工作策略,扮演不同的服务角色。 相似文献
162.
A. Magdalena Hurtado Carol A. Lambourne Kim R. Hill Karen Kessler 《Human nature (Hawthorne, N.Y.)》2006,17(2):129-154
The socioeconomic and ethnic characteristics of parents are some of the most important correlates of adverse health outcomes
in childhood. However, the relationships between ethnic, economic, and behavioral factors and the health outcomes responsible
for this pervasive finding have not been specified in child health epidemiology. The general objective of this paper is to
propose a theoretical approach to the study of maternal behaviors and child health in diverse ethnic and socioeconomic environments.
The specific aims are: (a) to describe a causal pathway between the utility that women obtain through work outside the home and through child care
and disease hazard rates in childhood using an optimization model; (b) to specify the influence of ethnic and socioeconomic factors on model constraints; (c) to use the model as a tool to learn about how different combinations of maternal wage labor and child care time might influence
child health outcomes in diverse social contexts; (d) to identify parameters that will require measurement in future research; (e) to discuss research strategies that will enable us to obtain these measurements; and (f) to discuss the implications of the model for biostatistical modeling and public health intervention. Optimization models
are powerful heuristic tools for understanding how ethnic, environmental, family, and personal characteristics can place important
constraints on both the quality and quantity of care that women can provide to their children. They provide a quantitative
appreciation for the difficult trade-offs that most women face between working in order to purchase basic goods that children
cannot do without (e.g., food, clothing, shelter, health insurance), and increasing offspring well-being through child care
(e.g., training in social skills, affection, protection from environmental hazards, help with homework).
The research was funded by a Faculty Scholars Award from the William T. Grant Foundation to A. Magdalena Hurtado.
A. Magdalena Hurtado, Ph.D., is an associate professor in the Department of Anthropology, University of New Mexico. Her research
interests include the origins of the sexual division of labor, epidemiology of indigenous peoples, disease susceptibility,
the development and intergenerational transmission of antigens and immune defense, immune function and allergic sensitization,
and trauma. She also works on public health interventions, biological capital and poverty, and land tenure and human rights
in native communities of South America.
Carol Lambourne, M.Sc., is a doctoral candidate in the Department of Anthropology, University of New Mexico. Her research
interests are evolutionary models of child and adolescent development, life history theory, family composition and investment
patterns, pubertal timing and psychosexual maturation, juvenile stress, and infanticide.
Kim Hill, Ph.D., is a professor in the Department of Anthropology, University of New Mexico. His research interests are modern
hunter-gatherers, including extensive fieldwork in lowland South America. Current topics of interest include human evolution,
economic strategies, life history theory, the evolution of cooperation, and the emergence of social norms enforced by punishment.
He is also involved in economic development, health and education projects with lowland South American native populations.
Karen Kessler received her M.S. in Anthropology from the University of New Mexico in 1996. Her research interests are the
application of mathematical modeling to the prevention of diabetes and other causes of morbidity and mortality in historical
populations. 相似文献
163.
A. E. Melchinger H. H. Geiger F. W. Schnell 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1986,72(2):231-239
Summary Three flint and three dent maize (Zea mays L.) inbred lines, their possible F1 crosses, F2 and backcross progenies, and all possible three-way crosses were evaluated in a three-year experiment for yield, ear moisture, and plant height. The purpose was to estimate genetic parameters in European breeding materials from (i) generation means analysis, (ii) diallel analysis of generation means, and (iii) analysis of F1 and three-way cross hybrids. Method (i) was based on the F-metric model and methods (ii) and (iii) on the Eberhart-Gardner (1966) genetic model; both models extended for heterotic maternal effects.Differences among generation means for yield and plant height were mainly attributable to dominance effects. Epistatic effects were significantly different from zero in a few crosses and considerably reduced heterosis in both traits. Additive x additive and domiance x dominance effects for yield were consistently positive and negative, respectively. Significant maternal effects were established to the advantage of generations with a heterozygous seed parent. In the diallel analysis, mean squares for dominance effects were greater than for additive effects for yield and plant height but smaller for ear moisture. Though significant for yield and plant height, epistatic variation was small compared to additive and dominance variation. Estimates of additive x additive epistasis for yield were significantly negative in 11 of 15 crosses, suggesting that advantageous gene combinations in the lines had been disrupted by recombination in the segregating generations. The analysis of hybrids supported the above findings regarding the analysis of variance. However, the estimates of additive x additive epistasis for yield were considerably smaller and only minimally correlated with those from the diallel analysis. Use of noninbred materials as opposed to materials with different levels of inbreeding is considered the main reason for the discrepancies in the results. 相似文献
164.
165.
Dawn B. Neill 《Human nature (Hawthorne, N.Y.)》2007,18(3):209-224
Health research has shown that overweight and obesity in children and adults are becoming significant public health problems
in the developing world. Evidence suggests that this phenomenon is more marked in urban than rural areas and may be associated
with modernization. However, the underlying reasons for this nutrition transition remain unclear. Dietary shifts, often in
conjunction with income and time constraints in urban environments, may entail a greater reliance on more convenient sugar
and fat-dense food. Also, the necessity of labor-intensive agricultural work to meet rural subsistence needs is supplanted
in urban environments by sedentary work. This paper extends the application of human behavioral ecology theory into the realm
of international development and policy by applying Kaplan’s embodied capital theory to explore differences in food habits
and nutritional status of Indo-Fijian children within the context of urbanization. Urban high-embodied-capital women demonstrate
higher rates of wage-earning employment than urban low-embodied-capital or rural women. Findings indicate that urban high-embodied-capital
households spend significantly more on food purchases, purchase a greater proportion of processed foods, and have children
with higher body mass indexes (BMI) than do urban low-embodied-capital or rural households. This suggests that urban high-embodied-capital
mothers, who tend to be employed, may be making trade-offs between income and food choices.
相似文献
Dawn B. NeillEmail: |
166.
Doenst Torsten Guthrie Patrick H. Taegtmeyer Heinrich 《Molecular and cellular biochemistry》1998,180(1-2):153-161
We tested the hypothesis that glycogen levels at the beginning of ischemia affect lactate production during ischemia and postischemic contractile function.Isolated working rat hearts were perfused at physiological workload with bicarbonate buffer containing glucose (10 mmol/L). Hearts were subjected to four different preconditioning protocols, and cardiac function was assessed on reperfusion. Ischemic preconditioning was induced by either one cycle of 5 min ischemia followed by 5, 10, or 20 min of reperfusion (PC5/5, PC5/10, PC5/20), or three cycles of 5 min ischemia followed by 5 min of reperfusion (PC3 × 5/5). All hearts were subjected to 15 min total, global ischemia, followed by 30 min of reperfusion. We measured lactate release, timed the return of aortic flow, compared postischemic to preischemic power, and determined tissue metabolites at selected time points.Compared with preischemic function, cardiac power during reperfusion improved in groups PC5/10 and PC5/20, but was not different from control in groups PC5/5 and PC3 × 5/5. There was no correlation between preischemic glycogen levels and recovery of function during reperfusion. There was also no correlation between glycogen breakdown (or resynthesis) and recovery of function. Lactate accumulation during ischemia was lowest in group PC5/20 and highest in the group with three cycles of preconditioning (PC3 × 5/5). Lactate release during reperfusion was significantly higher in the groups with low recovery of power than in the groups with high recovery of power.In glucose-perfused rat heart recovery of function is independent from both pre- and postischemic myocardial glycogen content over a wide range of glycogen levels. The ability to utilize lactate during reperfusion is an indicator for postischemic return of contractile function. 相似文献
167.
Shili Miao 《植被学杂志》1995,6(5):697-700
Abstract. In order to explore whether seed size affects plant response to elevated CO2, plants grown from red oak (Quercus rubra L.) acorns were studied for differences in their first year response to CO2 concentrations of 350 and 700 μl/l. Overall, at final harvest, total biomass of plants grown in elevated CO2 were 47 % larger than that of plants grown in ambient CO2. There were significant interactions between CO2 treatments and initial acorn mass for total biomass, as well as for root, leaf, and stem biomass. Although total biomass increased with increasing initial acorn mass for both high and ambient CO2 plants, high CO2 plants exhibited a greater increase than ambient CO2 plants, as indicated by a steeper slope in high CO2 plants. However, CO2 levels did not affect biomass partitioning traits, such as root/shoot ratio, leaf, stem, and root weight ratios, and leaf area ratio. These results suggest that variation in seed size or initial plant size can cause intraspecific variation in response to elevated CO2. 相似文献
168.
The active site metal in horse liver alcohol dehydrogenase has been studied by metal-directed affinity labeling of the native zinc(II) enzyme and that substituted with cobalt(II) or cadmium(II). Reversible binding of bromoimidazolyl propionic acid to the cobalt enzyme blueshifts the visible absorption band originating from the catalytic cobalt atom at 655 to 630 nm. Binding of imidazole to the cobalt(II) enzyme redshifts the 655 nm band to 667 nm. Addition of bromoimidazolyl propionic acid blueshifts this 667 nm band back to 630 nm. This proves direct binding of the label to the active site metal in competition with imidazole. The affinity of the label for the reversible binding site in the three enzymes follows the order Zn ? Cd ? Co. After reversible complex formation, bromoimidazolyl propionic acid alkylates cysteine-46, one of the protein ligands to the active site metal. The nucleophilic reactivity of this metal-mercaptide bond in each reversible complex follows the order Co ? Zn ? Cd. 相似文献
169.
Ogura Y Iemitsu M Naito H Kakigi R Kakehashi C Maeda S Akema T 《Biochemical and biophysical research communications》2011,(4):756-760
Macroautophagy (autophagy) is an intracellular catalytic process. We examined the effect of running exercise, which stimulates cardiac work physiologically, on the expression of microtubule-associated protein 1 light chain 3 (LC3)-II, an indicator of autophagy, as well as some autophagy-related proteins in rat cardiac muscle. The left ventricles were taken from rats immediately (0 h), and at 0.5 h, 1 h or 3 h after a single bout of running exercise on a treadmill for 30 min and also from rats in a rest condition. In these samples, we evaluated the level of LC3-II and p62, and the phosphorylation level of mammalian target of rapamycin (mTOR), Akt and AMP-activated protein kinase alpha (AMPKα) by Western blotting. The exercise produced a biphasic change in LC3-II, with an initial decrease observed immediately after the exercise and a subsequent increase 1 h thereafter. LC3-II then returned to the rest level at 3 h after the exercise. A negative correlation was found between the LC3-II expression and mTOR phosphorylation, which plays a role in inhibiting autophagy. The exercise increased phosphorylation of AMPKα, which stimulates autophagy via suppression of mTOR phosphorylation, immediately after exercise. The level of p62 and phosphorylated Akt was not altered significantly by the exercise. These results suggest for the first time that a single bout of running exercise induces a biphasic change in autophagy in the cardiac muscle. The exercise-induced change in autophagy might be partially mediated by mTOR in the cardiac muscle. 相似文献
170.