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181.
A number of models of behaviour have been applied to contraception use including subjective expected utility theory and social cognition models. Whilst correlates of contraception use have been identified, the limitations of these models include their failure to consider either contextual factors or changes in contraception use over time. Researchers have called for integrated and dynamic models of contraception use, which can be related to the changing contraception use of individual women and can also be readily operationalised to explore within and between subject differences in contraception use. The present study therefore used a qualitative methodology to explore women's contraceptive histories and to enable women to define the issues from their perspectives, resulting in a model of contraception use that is firmly located within the context of their own lives and allows an investigation of the factors and processes involved in changes in contraception use/non-use over time. This model conceptualises the predictors of contraception use in terms of the meaning and importance of a range of social goals, perceptions of vulnerability and constraints on or facilitators of contraception. Further the dynamic nature of these factors is described and it is illustrated how these core components vary over time according to situation, experience, and new information. The paper outlines the relevance of the findings for different models of decision-making processes and highlights the way that the model addresses the limitations of previous approaches.  相似文献   
182.
Magnetic Resonance Spectroscopy (MRS) and its association with neuropsychological functioning was examined in the chronic injury phase of paediatric traumatic brain injury (TBI). Fifteen children, aged 10-16 years, with severe TBIs were compared with 15 controls, matched for age and gender. The TBI group was found to have significantly lower levels of N-acetyl aspartate (NAA) and Choline (Cho) in the right frontal lobe and generally displayed reduced performances on neuropsychological tests. A correlation between metabolites and reaction times was also obtained. Findings indicate a role of proton MRS as a measure of neuronal integrity following severe paediatric TBI and suggest a potential association of MRS with specific neuropsychological impairments.  相似文献   
183.
The present article aims to resolve the debate on the degree of benefit of processing tool or die steels by cryogenic treatment. This has been done by measuring transition loads for quenched and tempered die steel with and without cryogenic treatment. The wide range of reported degrees of improvement of wear resistance by cryotreatment is explained by the operative modes and mechanisms of sliding wear considering the wear rate ratio of conventionally treated to cryotreated steels on a two-dimensional map.  相似文献   
184.
The recrystallization behaviour of a cold-rolled, low-density, low-alloy duplex-phase alloy (Fe–6.57Al–3.34Mn–0.18C, wt.%) has been studied. Temperature-resolved X-ray diffraction and dilatometry showed that the alloy recrystallizes at 850?°C during continuous heating. However, electron back-scattered diffraction investigations using Kernel average misorientation revealed that during annealing ferrite recrystallizes at lower temperatures while austenite remains strained up to 1200?°C. This study underlines the complexity of recrystallization of a microstructure comprising of constituents with high and low stacking fault energy.  相似文献   
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This study explores the personal meaning of head and neck cancer for individuals, with particular reference to the impact on the self. It employs interpretative phenomenological and repertory grid analysis with 10 people, all of whom have undergone surgical treatment for head and ceck cancer. Four themes emerged: namely, destruction of self, altered relations with the body, disenfranchised self, and conservation of self. Repertory grid analysis validated and enriched understanding of these findings. Participants described how head and neck cancer inflicted a fundamental attack on their sense of self. Nonetheless, participants were dynamic in their self-management and detailed an active process to retain a positive sense of self.  相似文献   
187.
High-resolution neuroimaging modalities are used often in studies involving healthy volunteers. Subsequently, a significant increase in the incidental discovery of asymptomatic intracranial abnormalities raised the important ethical issues of when follow-up and treatment may be necessary. We examined the literature to establish a practical set of criteria for approaching incidental findings. Our objective is to develop an algorithm for when follow-up may be important and to provide recommendations that would increase the likelihood of follow-up. A systematic literature search was performed using the PubMed and MEDLINE databases to identify articles describing brain tumors and intracranial aneurysms. The treatment algorithm we present suggests that incidental intracranial masses suspicious for glioma should be biopsied or resected, while other masses are to be followed with serial imaging based on the expected growth pattern. Lack of follow-up can result in adverse outcomes that can be mitigated by using technology to facilitate communication and improve follow-up care. The importance of training physicians to be good communicators is also stressed. New technology including automated telephone systems, texting and email will improve access to patients and hopefully encourage compliance and follow-up.  相似文献   
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189.
The goal of the Familial Dilated Cardiomyopathy (FDC) Research Project, initiated in 1993, has been to identify and characterize FDC genetic cause. All participating individuals have been consented for the return of genetic results, an important but challenging undertaking. Since the inception of the Project we have enrolled 606 probands, and 269 of these had 1670 family members also enrolled. Each subject was evaluated for idiopathic dilated cardiomyopathy (IDC) and pedigrees were categorized as familial or sporadic. The coding regions of 14 genes were resequenced in 311 to 324 probands in five studies. Ninety-two probands were found to carry nonsynonymous rare variants absent in controls, and with Clinical Laboratory Improvement Amendment of 1988 (CLIA) compliant protocols, relevant genetic results were returned to these probands and their consented relatives by study genetic counselors and physicians in 353 letters. In 10 of the 51 families that received results >1 year ago, at least 23 individuals underwent CLIA confirmation testing for their family’s rare variant. Return of genetic results has been successfully undertaken in the FDC Research Project. This report describes the methods utilized in the process of returning research results. We use this information as a springboard for providing guidance to other genetic research groups and proposing future directions in this arena.  相似文献   
190.
A qualitative case study design was used to explore educational risk factors that may contribute to psychological truancy in a Lesotho secondary school. Purposively sampled teachers (n = 4, females = 50%) and pupils (n = 4, females = 75%), who have experience of psychological truancy, took part in a focus group and individual interviews. Inductive content analysis was used to analyse data emanating from the interviews. The findings indicate that pupil–teacher relationships, the use of English as medium of instruction and a lack of resources may be educational risk factors contributing to psychological truancy. Positive pupil–teacher relationships and active classroom engagement are prerequisites for successful and active learning.  相似文献   
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