全文获取类型
收费全文 | 7658篇 |
免费 | 2598篇 |
国内免费 | 546篇 |
专业分类
10802篇 |
出版年
2024年 | 15篇 |
2023年 | 113篇 |
2022年 | 111篇 |
2021年 | 275篇 |
2020年 | 399篇 |
2019年 | 794篇 |
2018年 | 647篇 |
2017年 | 813篇 |
2016年 | 793篇 |
2015年 | 627篇 |
2014年 | 607篇 |
2013年 | 1141篇 |
2012年 | 419篇 |
2011年 | 414篇 |
2010年 | 334篇 |
2009年 | 367篇 |
2008年 | 364篇 |
2007年 | 352篇 |
2006年 | 343篇 |
2005年 | 284篇 |
2004年 | 248篇 |
2003年 | 227篇 |
2002年 | 206篇 |
2001年 | 178篇 |
2000年 | 159篇 |
1999年 | 113篇 |
1998年 | 59篇 |
1997年 | 51篇 |
1996年 | 35篇 |
1995年 | 41篇 |
1994年 | 48篇 |
1993年 | 29篇 |
1992年 | 17篇 |
1991年 | 30篇 |
1990年 | 18篇 |
1989年 | 18篇 |
1988年 | 18篇 |
1987年 | 11篇 |
1986年 | 9篇 |
1985年 | 12篇 |
1984年 | 15篇 |
1983年 | 5篇 |
1982年 | 7篇 |
1981年 | 6篇 |
1980年 | 10篇 |
1979年 | 6篇 |
1978年 | 5篇 |
1977年 | 6篇 |
1976年 | 2篇 |
1975年 | 1篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
941.
Based on the Theory of Planned Behaviour (TPB), the purpose of this investigation was to examine the directionality of the association among condom use, intention, attitudes, subjective norms and perceived behavioural control. The present study investigated the nature of these relationships using a longitudinal cross-lagged design applied to data from a cohort of 958 randomly selected Italian adults. Using structural equation modelling, two cross-lagged panel analyses revealed reciprocal relationships between intention and attitudes and between intention and condom use. Contrary to expectations, baseline subjective norms and perceived behavioural control did not predict subsequent intention to use condom when controlled for the autoregressive effect of intention at T1 on the same variable at T2. Also, perceived behavioural control at T1 did not influence condom use at T2 after controlling for the effect of baseline intention. The possibility of reciprocity was also tested for all relations and significant results were found. The moderation effect of perceived behavioural control on the relationship between intention and condom use was not significant. The differences in age, gender and partnership status were taken into account in the analyses. 相似文献
942.
Ronald C. Plotnikoff Sonia Lippke Kerry Courneya Nicholas Birkett Ronald Sigal 《Psychology & health》2013,28(1):7-23
Physical activity (PA) plays a key role in the management of Type 1 (T1D) and Type 2 diabetes (T2D) but there are few theory-based, effective programs to promote PA for individuals with diabetes. The purpose of this study was to investigate the utility of the Theory of Planned Behaviour (TPB) in understanding PA in an adult population with T1D or T2D. A total of 2311 individuals (691 T1D; 1614 T2D) completed self-report TPB constructs of attitude, subjective norms, perceived behavioural control (PBC), intention and PA at baseline and 1717 (524 T1D; 1123 T2D) completed the PA measure again at 6-month follow-up. Multi-group Structural Equation Modelling was conducted to: (1) test the fit of the TPB structure (2) determine the TPB structural invariance between the two types of diabetes and (3) to examine the explained variances in PA and compare the strength of associations of the TPB constructs in the two types of diabetes. The TPB constructs explained ≥40% of the variance in intentions for both diabetes groups. In cross-sectional models, the TPB accounted for 23 and 19% of the variance in PA for T1D and T2D, respectively. In prospective models, the TPB explained 13 and 8% of the variance in PA for T1D and T2D, respectively. When adjusting for past PA behaviour, the impact of PBC and intention on behaviour was reduced in both groups. The findings provide evidence for the utility of the TPB for the design of PA promotion interventions for adults with either T1D or T2D. 相似文献
943.
Objective: To develop a conceptual understanding of the process of adapting to the self-management of type 1 diabetes during adolescence.Design: Participants were recruited from a National Health Service paediatric diabetes service within the south-west of England which runs six countywide diabetes clinics. Thirteen interviews were conducted using a social constructivist grounded theory approach.Results: The findings illustrate how self-management can be understood in terms of a continuum-based framework, ranging from difficulties with, to successful self-management. Adaptation within the continuum can further be understood by specific transitional phases and process mechanisms, providing further depth to individuals’ experiences of adaptation.Conclusion: This investigation provides a conceptual understanding of the complex issues adolescents encounter while adapting to and integrating a diabetes self-management regime into their lives. It provides an invaluable framework for exploring psychological mechanisms and contextualising them within a self-management continuum. Implications for healthcare professionals are discussed and further research proposes whether the model could be applicable to other chronic illnesses. 相似文献
944.
Abstract The present study was designed to examine the utility of the theory of reasoned action (Fishbein and Azjen, 1975) in relation to people's propensity to engage in a range of different safe sex strategies, including engaging in an exclusive sexual relationship, avoiding casual sex, and asking sexual partners about their previous sexual and IV drug use history. It was proposed that the intention to engage in a particular safe sex practice would be influenced by the person's attitude towards engaging in the practice, as well as his or her perception of the extent to which others thought they should do so (subjective norm), while behavioural intentions were proposed to predict actual behaviour. The study was also designed to examine whether, after control of the effects of the components of the theory of reasoned action, the person's generalised control beliefs would explain any additional variance in either behavioural intentions or actual behaviour. One hundred and two sexually active heterosexual students participated in the study. At the first wave of data collection, subjects completed measures of intentions, attitudes, and norms appropriate to each of the different behaviours. Measures of actual behaviour were obtained at follow-tip (three months after first period of data collection). The results of the study indicated that attitudes and norms predicted intentions for avoiding casual sex and asking sexual partners about their previous sexual and IV drug use history, while intentions predicted actual behaviour for all three safe sex strategies. Although there were no significant main effects of control beliefs on intentions or behaviour, subjects with internal control beliefs were more likely than their counterparts with external control beliefs to behave in accordance with their intentions to engage in an exclusive sexual relationship and ask sexual partners about their previous sexual and IV drug use history. Additional analyses revealed that the levels and determinants of intentions and actual behaviour were, in general, similar for males and females. 相似文献
945.
The purpose of this study was to explore whether sedentary behavior cognitions explain physical activity (PA) intention and behavior when integrated within the theory of planned behavior framework (TPB). A random community sample of 206 adults and a sample of 174 undergraduate students completed measures of the TPB pertaining to PA and four popular leisure-time behaviors (TV viewing, computer use, sedentary hobbies, and sedentary socializing) and an adapted Godin Leisure-Time Exercize Questionnaire (community sample = cross-sectional, undergraduate sample = 2-week prospective). Results using ordinary least squares regression provided evidence that TV viewing intention explains additional variance in PA behavior, and affective attitude (community sample) and perceived behavioral control (undergraduate sample) towards TV viewing explains additional variance in PA intention even after controlling for PA-related TPB constructs. These results underscore the potential value of adding sedentary control interventions in concert with PA promotion. 相似文献
946.
947.
The theory of planned behaviour is one of the most widely used models of decision-making in the health literature. Unfortunately, the primary method for assessing the theory's belief-based expectancy-value models results in statistically uninterpretable findings, giving rise to what has become known as the ‘expectancy-value muddle’. Moreover, existing methods for resolving this muddle are associated with various conceptual or practical limitations. This study addresses these issues by identifying and evaluating a parsimonious method for resolving the expectancy-value muddle. Three hundred and nine Australian residents aged 18–24 years rated the expectancy and value of 18 beliefs about posthumous organ donation. Participants also nominated their five most salient beliefs using a dimensional salience approach. Salient beliefs were perceived as being more likely to eventuate than non-salient beliefs, indicating that salient beliefs could be used to signify the expectancy component. The expectancy-value term was therefore represented by summing the value ratings of salient beliefs, an approach that predicted attitude (adjusted R 2?=?0.21) and intention (adjusted R 2?=?0.21). These findings suggest that the dimensional salience approach is a useful method for overcoming the expectancy-value muddle in applied research settings. 相似文献
948.
The current studies examine proximal and distal mortality salience effects on the willingness to engage in health-promoting activities and explore the roles of age and self-esteem. In Study 1, 164 participants completed a self-esteem scale, were assigned to a mortality salience or a neutral condition, and then completed a scale, tapping their willingness to engage in health promoting activities. Findings revealed that in the proximal mode, mortality salience led the young and middle-aged adults to report higher willingness to promote health behaviors, whereas older adults tended to show a lower willingness to promote their health compared to the control condition. In Study 2, a total of 251 participants completed the same series of questionnaires, including a distracting task immediately after the mortality salience manipulation. Findings revealed that, in the distal mode, whereas death reminders did not affect young adults, mortality salience led middle-aged participants to express higher willingness to conduct health-promoting behaviors than in a control condition. The mortality salience induction did not affect older adults with high self-esteem, but led low self-esteem individuals to report higher willingness to promote their health. The differences between the reactions of the different age groups in both the defense modes are discussed in view of the terror management theory. 相似文献
949.
Bruce Bolam 《Psychology & health》2013,28(2):273-274
Abstract Recent theoretical and empirical research has challenged the assumption of health psychologists employing social cognitive models that beliefs can confidently be inferred on the basis of questionnaire responses. It is charged that responses to questionnaires are a function of the intelligibility of the items, constructs and theoretical framework to survey participants. To investigate this contention, cognitions specified by Protection Motivation Theory (PMT) were measured with respect to intentions to use a condom and intentions to use dental floss. Three alternative formats of a questionnaire which varied the order of presentation of PMT items were distributed to student samples. Analyses showed that while questionnaire format did not affect the reliability of cognition measures, there was some variation in the significance and strength of correlations between PMT cognitions across formats. Individual differences in social desirability and salience of the target behaviour had small and predictable effects upon reliabilities and intercorrelations. Implications for the measurement of health beliefs and the status of questionnaire responses are outlined and suggestions are made for controlling bias associated with respondents' capacity to “read” a questionnaire. 相似文献
950.
H. Y. Uzunok Ertuǧrul Karaca A. Başoǧlu G. P. Srivastava 《Philosophical Magazine Letters》2013,93(9):375-391
ABSTRACTWe present results for the structural, electronic, vibrational, and electron-phonon coupling properties of LaSn3 and CaSn3 adopting the simple cubic AuCu3-type structure obtained using the the generalised gradient approximation of the density functional theory and plane wave ab initio pseudopotential method. Our electronic results show that both materials display metallic character with several bands, which have mainly Sn 5p character, crossing the Fermi level. The calculated phonon spectrum of LaSn3 accords very well with reported experimental measurements. The weights of the peaks in the Eliashberg spectral function of both compounds are enhanced with the use of experimental lattice constant in our electron-phonon calculation, increasing the value of average electron phonon coupling parameter from 0.876 to 0.937 for LaSn3 (by 7%) and from 0.642 to 0.725 for CaSn3 (by 13%). The use of experimental lattice constant also improves the agreement between theoretical and experimental values of the superconducting temperature for both compounds. 相似文献