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Acrylamide forms primarily from a reaction between reducing sugars (e.g., glucose and fructose) and an amino acid (asparagine, Asn) formed naturally in foods, including potatoes. This reaction occurs when carbohydrate‐rich foods are heated at temperatures above 120 °C. Multiple potato varieties were transformed with potato genomic DNA that results in down‐regulation of the expression of the asparagine synthetase‐1 gene (Asn1), significantly reducing synthesis of free Asn, and consequently lowering the potential to form acrylamide during cooking. These potatoes with low acrylamide potential (LAP) were tested in agronomic trials, and processed into French fries and potato chips. Decreased levels of acrylamide were measured in these cooked food products when derived from LAP potatoes compared with those derived from conventional potatoes. These reductions can be directly attributed to reduction in Asn levels in the LAP potatoes. The corresponding average reduction in exposure to acrylamide from French fry and potato chip consumption is estimated to be 65%, which would amount to approximately a 25% reduction in overall dietary exposure. Considering that children consume nearly three times more acrylamide than adults on a per kg body weight basis, they would experience the most impact from the reduced acrylamide associated with LAP potatoes. The potential public health impacts, in context of dietary acrylamide exposure reduction, are discussed in this study.  相似文献   
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Abstract

Recently, the study of the lifetime of systems in reliability and survival analysis in the presence of several causes of failure (competing risks) has attracted attention in the literature. In this paper, series and parallel systems with exponential lifetime for each item of the system are considered. Several causes of failure independently affect lifetime distributions and observations of failure times of the systems are considered under progressive Type-II censored scheme. For series systems, the maximum likelihood estimates of parameters are computed and confidence intervals for parameters of the model are obtained using Fisher information matrix. For parallel systems, the generalized EM algorithm which uses the Newton-Raphson algorithm inside the EM algorithm is used to compute the maximum likelihood estimates of parameters. Also, the standard errors of the maximum likelihood estimates are computed by using the supplemented EM algorithm. The simulation study confirms the good performance of the introduced approach.  相似文献   
4.
ObjectiveTo evaluate the effect of mother–infant immediate skin-to-skin contact on primiparous mother's breastfeeding self-efficacy.Study designA randomised control trial.SettingsThe study was conducted in Omolbanin obstetrics hospital (large tertiary hospital), Mashhad, Iran.Participants114 18–35 year-old primiparous, Iranian, healthy and full term mothers who anticipated normal vaginal delivery and intended to breastfeed their babies.InterventionSkin-to-skin contact immediately after birth and then controlling breastfeeding self-efficacy at 28 days postpartum.Main outcome measureMaternal breastfeeding self-efficacy at 28 days postpartum and success in first breastfeeding and mean time of first breastfeeding initiation.ResultsA total of 92 mother–infant dyads (47 dyads in skin-to-skin care skin-to-skin contact group and 45 dyads in routine care group) were monitored and analysed. In skin-to-skin contact group, breastfeeding self-efficacy was 53.42 ± 8.57 SD as compared to 49.85 ± 5.50 SD in routine care group which is significantly higher in skin-to-skin contact group (p = 0.0003).Successful breastfeeding initiation rate was 56.6% in skin-to-skin contact group as compared to 35.6% in routine care group (p = 0.02).Time to initiate first feed was 21.98 ± 9.10 SD min in SSC group vs. 66.55 ± 20.76 min in routine care group (p < 0.001).ConclusionMother–infant immediate skin-to-skin contact is an easy and available method of enhancing maternal breastfeeding self-efficacy. High breastfeeding self-efficacy increases exclusive breastfeeding duration.  相似文献   
5.
Non-Gaussian spatial responses are usually modeled using spatial generalized linear mixed model with spatial random effects. The likelihood function of this model cannot usually be given in a closed form, thus the maximum likelihood approach is very challenging. There are numerical ways to maximize the likelihood function, such as Monte Carlo Expectation Maximization and Quadrature Pairwise Expectation Maximization algorithms. They can be applied but may in such cases be computationally very slow or even prohibitive. Gauss–Hermite quadrature approximation only suitable for low-dimensional latent variables and its accuracy depends on the number of quadrature points. Here, we propose a new approximate pairwise maximum likelihood method to the inference of the spatial generalized linear mixed model. This approximate method is fast and deterministic, using no sampling-based strategies. The performance of the proposed method is illustrated through two simulation examples and practical aspects are investigated through a case study on a rainfall data set.  相似文献   
6.
This study examined the effects of some work demands-resources on two dimensions of work-to-family interface among Iranian employees. The results of canonical correlation and multiple-regression showed that among work resources (i.e., social support and autonomy), social support was associated negatively with work-to-family conflict and autonomy was associated positively with work-to-family facilitation. Also, among work demands (i.e., job demands and working hours), job demands were associated with both work-to-family conflict and work-to-family facilitation. Unlike previous studies, working hours shows a positive association with work-to-family facilitation, which may be explained by the specific cultural context in Iran. The findings of the study will be of importance to employees and organizations.
Aboulghasem NouriEmail:
  相似文献   
7.
The voices of people experiencing poverty are underrepresented in social work research, public policy development, and practice interventions. This study explored the social class attributions of clients receiving poverty-related services through qualitative interviews. Findings reveal dynamic contributions of individual, environmental, and structural factors of social class positioning and significant stress and stigmatization associated with experiencing economic hardship. Participants indicate a sense of lived contradiction, viewing social class to be the result of fate while simultaneously endorsing individualistic attributions of poverty. Results have implications for social work research and practice, as well as poverty-related policy and program development.  相似文献   
8.
Clustered binary responses are often found in ecological studies. Data analysis may include modeling the marginal probability response. However, when the association is the main scientific focus, modeling the correlation structure between pairs of responses is the key part of the analysis. Second-order generalized estimating equations (GEE) are established in the literature. Some of them are more efficient in computational terms, especially facing large clusters. Alternating logistic regression (ALR) and orthogonalized residual (ORTH) GEE methods are presented and compared in this paper. Simulation results show a slightly superiority of ALR over ORTH. Marginal probabilities and odds ratios are also estimated and compared in a real ecological study involving a three-level hierarchical clustering. ALR and ORTH models are useful for modeling complex association structure with large cluster sizes.  相似文献   
9.
Social cohesion is a key concept in development studies. Weak social cohesion is often related to slow economic growth and (violent) conflict. So far few attempts have been made to measure this complex concept in a systematic manner. This paper introduces an innovative method to measure national-level social cohesion based on survey data from 19 African countries. We distinguish three dimensions of social cohesion; i.e. the extent of perceived inequalities, the level of societal trust, and the strength of people’s adherence to their national identity. Importantly, our Social Cohesion Index (SCI) is based on individuals’ perceptions vis-à-vis these three different dimensions of social cohesion rather than certain macro-level ‘objective’ indicators such as GDP/capita or Gini-coefficients. We develop two social cohesion indices: a national average SCI and a Social Cohesion Index Variance-Adjusted (SCIVA); the latter one takes into account the level of variation across different ethnic groups within countries. The SCI and SCIVA are computed for and compared across nineteen African countries for the period 2005–2012 on the basis of Afrobarometer survey rounds 3, 4 and 5. We also investigate quantitatively the relationship between countries’ levels of social cohesion and the occurrence of a range of conflict events. As expected, we find that countries with low levels of social cohesion in a particular year according to our SCI are more likely to experience a range of different violent conflict events in the subsequent year.  相似文献   
10.
This brief report provides a first look at self-reported instances of elder abuse by a sample of people 60 years and older living in Qazvin, Iran. Six hundred community-dwelling persons, drawn from the registry files of each health center in Qazin, completed questionnaires during April to October 2012. At least 80% of the participants reported experiencing some form of psychological abuse, financial abuse, and/or neglect at least once during a 2-month period. Physical and sexual abuse were rarely reported. Despite a strong Iranian cultural emphasis on respect for elders, the self-reporting of elder abuse, especially psychological abuse, is greater than our expectation. We recommend that health-related policies and programs begin to identify elder abuse and neglect as a first step in prevention.  相似文献   
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