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71.
The normal hematological values in various phases of the rat life provide a valuable guide to researchers and could be useful for experimental works. However, database information available on the literature are incomplete. Aim: This study aimed to present normal hematological parameters of young and aged rats.

Methods: Male and female rats were distributed into seven experimental groups with 1, 2, 3, 6, 12, 18, and 24 months of age. Blood samples taken from the tails were analyzed. Normal hematological values were determined for each age group.

Results: Rats showed a progressive weight gain with advancing age, predominantly after 3 months of life. With advancing age, differences were found on hematological parameters: some of them showed a progressive rise with age and others did not. Hemoglobin levels and hematocrit did not change while the number of circulating red blood cells suffered slight increase.

Conclusion: The present study determined the normal values for absolute and relative hematological parameters in Wistar rats from 2 to 24 months for male and female rats. The results can be used in studies of effects of aging, feeding, and medications on growing and aging rats.  相似文献   

72.
The Sustainable Development Goals (SDG) list the objectives and targets that should be addressed to solve the global issues regarding sustainable development. They encompass the social, economic and environmental dimensions and search for solutions that are able not only to monitor but also to control the operational indicators attributed to each objective. It is expected that many of these indicators are associated to each other and the accurate understanding of these correlations allows to build predictive statistical models that can improve the monitoring and controlling of variables. It would increase the rate of success in achieving the SDG. This study tested a linear multivariate model able to predict the human development index based on environmental variables which are related to SDG 3 (health), 4 (education), 8 (sustainable economic growth and decent work) and 15 (protect, restore and promote sustainable use of terrestrial ecosystems). We fitted the models using the Linear Discriminant Analysis and Best Subset Selection applied to a Linear Multivariate Regression. The model predictive ability was assessed by R2 and cross-validation (CV). The results showed that exposure to unsafe sanitation, access to drinking water, tree cover loss, unsafe water quality, wastewater treatment level, and household air pollution are excellent predictors of human development index of a population, with R2 = 0.94 and 10-fold CV Mean Squared Error equal to 0.0014. This tool can help stakeholders to monitor and control indicators attributed to good health and well-being, quality education, clean water and sanitation, decent work and economic growth, sustainable cities and communities and life on land sustainable development goals.  相似文献   
73.
This study aims to describe the painfulness applied to situations of teaching-learning of a Big Band in a School of Music of a Brazilian Federal University. Moreover, the concept of what painful noise is will be developed, applied to this context. After Ergonomic Work Analysis [2], the following variables were selected to characterize the painful noise: volume, height, frequency, sound confluence and reverberation. To relate the influence of painful noise on modes operatives, were explained the operative strategies used by teacher and students during the performance in group of this Big Band.  相似文献   
74.
Green roofs have been described as technical solutions to overcome urban environmental problems, such as decrease of vegetation and stormwater management. In the present study, two pilot 20 m2 extensive green roofs were implemented in an urban Mediterranean region, at a 1st storey on a warehouse building structure, in order to test the adequacy of different substrates for supporting aromatic plants (Lavandula dentata, Helichrysum italicum, Satureja montana, Thymus caespititius and Thymus pseudolanuginosus). Experimental substrates included expanded clay and granulated cork as main components, supplemented with organic matter and crushed egg shell. A commercial substrate that obeys to FLL guidelines was also tested. Plant growth was assessed and compared within each platform. All experimental substrates proved to be adequate for vegetation growth, with the combination of 70% expanded clay, 15% organic matter and 15% crushed egg shell showing the best results regarding plant establishment and growth over time. Water runoff quality parameters - turbidity, pH, conductivity, NH4 +, NO3 ?, PO4 3? - met standard values required for water reuse for non-potable purposes, such as toilet flushing or irrigation. Preliminary qualitative thermographic measurements comparing surface temperature of different plant species and the substrate showed that temperature of vegetation surface was lower than substrate, reinforcing green roofs benefits of lowering air temperature in their surroundings. The present research shows that aromatic vegetation combined with clay substrates are suitable for green roofs located in countries of the Mediterranean region.  相似文献   
75.
The literature on women in STEM areas displays the barriers that women face at scientific workplaces, showing important interaction where they do and undo gender. However, there is a lack of research about the extent men and women do and undo gender in networking environments. This is a participant observation at Human-Computer Interactions annual conferences in a mainly male-dominated environment. It explored how researchers are ‘doing’ and ‘undoing’ gender focusing on two main dimensions: the gender roles adopted by men and women during the presentations and social activities, and the gender contents exposed in their research talks. A first result shows that sex and gender issues are trivialized in research contents by both men and women researchers. A second result reveals that men and women unintentionally and successively ‘do’ and ‘undo’ gender as a strategy to fit into a neutral and accepted identity of engineering and computer scientists.  相似文献   
76.
Cet article étudie de quelle façon et à quel moment les journaux, les ONG environnementales, les entreprises privées et le gouvernement convergent autour des événements environnementaux. En utilisant les données sur le déversement de pétrole BP en 2010 tirées des journaux aux États‐Unis, au Canada et en Grande‐Bretagne et des communiqués de presses de Greenpeace, du Club Sierra, de Halliburton, de Transocean, d’Exxon/Mobil et les annonce de presse de la secrétaire de presse pour le Maison Blanche, nous étudions la capacité d'un événement à faire converger des actions sociales et politiques. En concevant les événements comme des actants, nous vérifions les arguments tirés des publications sur les mouvements sociaux et sur la définition de l'agenda politique à propos du timing, de la simplicité et de la visualité afin de comprendre comment les acteurs politiques convergent. Nous observons que l'effet de convergence est lié au timing, mais pas à la simplicité ou à la visualité. This paper examines how and when newspapers, environmental nongovernmental organizations, businesses, and the government converge on environmental events. Using data on the 2010 BP Oil Spill from newspaper articles in the United States, Canada, and the United Kingdom, press releases by Greenpeace and Sierra Club, press releases by BP, Halliburton, Transocean, ExxonMobil, and Shell, and press statements by the White House Press Secretary, we examine an event's potential to trigger convergence of social and political action. By treating events as political actants, we examine arguments from the agenda‐setting and social movement literatures on timing, simplicity, and visuality to understand when political actors converge. We find that convergence is related to temporal cycles but not simplicity or visuality.  相似文献   
77.
Some asymptotic expansions not necessarily related to the central limit theorem are studied. We first observe that the smoothing inequality of Esseen implies the proximity, in the Kolmogorov distance sense, of the distributions of the random variables of two random sequences satisfying a sort of general asymptotic relation. We then present several instances of this observation. A first example, partially motivated by the the statistical theory of high precision measurements, is given by a uniform asymptotic approximation to (g(X + μ n )) n∈?, where g is some smooth function, X is a random variable and (μ n ) n∈? is a sequence going to infinity; a multivariate version is also stated and proved. We finally present a second class of examples given by a randomization of the interesting parameter in some classical asymptotic formulas; namely, a generic Laplace's type integral, randomized by the sequence (μ n X) n∈?, X being a Gamma distributed random variable.  相似文献   
78.
In this study, we aim to develop a demand classification methodology for classifying and controlling inventory spare parts subject to stochastic demand and lead time. Using real data, the developed models were tested and their performances were evaluated and compared. The results show that the Laplace model provided superior performance in terms of service level, fill rate (FR) and inventory cost. Compared with the current system based on normal distribution, the proposed Laplace model yielded significant savings and good results in terms of the service level and the FR. The Laplace and Gamma optimisation models resulted in savings of 82 and 81%, respectively.  相似文献   
79.
ABSTRACT

Objective: Participation in recreational sport clubs on campus is a popular student activity nationwide. These sport-based organizations provide a host of benefits within recognized dimensions of health and wellness. Understanding participants’ motives for engaging in these types of activities can provide insight in design and delivery and enhance participant health. This study focuses on outcomes related to the social motivations for participation in a recreational sport swim club and their potential relationship to social health. Participants: Current members of recreational swimming clubs were contacted for participation in the study from March-April 2016. Methods: A Leisure Motivation Scale (LMS) survey was sent electronically to 196 collegiate swim clubs nationwide. Aggregate and multivariate analyses from 1011 responses were conducted to examine the social motivation and motivational differences of participants. Results: Social motivations emerged as the predominate motivational construct, indicating important implications for social health improvement through participation. Demographically, results indicated no statistically significant differences in social motivation factors based on participant gender, and statistically significant differences within participant race, university affiliation and practice frequency. Conclusions: Impacts of these findings are important for practitioners and participants when evaluating the potential these programs have to influence participant social health.  相似文献   
80.
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