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1.
Summary The aim of this report was to investigate the neural processes of movement initiation and control in which the basal ganglia play an essential role. Single-neuron activity was recorded in the putamen of monkeys performing learned arm movements initiated in three different modes: sensorially guided, internally-timed self-initiated and memory guided. There were no significant differences in the magnitude and timing of both prime mover and supporting muscle activity between the three modes of movement. Over half of the task-related neurons showed strong activity in one of the three modes of movement initiation, but were only slightly activated in the other two modes. No clear preference for a particular movement mode was evident in the population of putamen neurons as a whole. These results are consistent with the hypothesis that there are heterogeneous groups of neurons in the putamen, and that each group of neurons participates in retrieving a different kind of information required for movement based on either external sensory events or on internally stored information.  相似文献   
2.
3.
Alcohol exposure on postnatal days (PND) 4-9 in the rat adversely affects hippocampal anatomy and function and impairs performance on a variety of hippocampus-dependent tasks. Exposure during this developmental window reveals a linear relationship between alcohol dose and spatial learning impairment in the context preexposure facilitation effect (CPFE), a hippocampus-dependent variant of contextual fear conditioning. The purpose of the current report was to examine the effect of a range of alcohol doses administered during a narrower window, PND7-9, than previously reported (Experiment 1) and to begin to determine which memory processes involved in this task are impaired by developmental alcohol exposure (Experiment 2). In Experiment 1, rats pups received a single day binge alcohol dose of either 2.75, 4.00, 5.25 g/kg/day or were sham-intubated (SI) from PND7-9. Conditioned freezing during the test day was evident in all dosing groups, except for Group 5.25 g, indicating no graded dose-related behavioral deficits with alcohol exposure limited to PND7-9. In Experiment 2, rat pups were exposed to the highest effective dose from Experiment 1 (5.25 g/kg/day) or were sham intubated over PND7-9. During training, rats remained in the conditioning context for 5-min following immediate shock delivery. During this test of post-shock freezing, both SI and alcohol-exposed rats given prior exposure to the conditioning context showed comparable freezing levels. Since alcohol-exposed rats showed normal post-shock freezing, deficits by these rats on the test day likely reflect a failure to consolidate or retrieve a context-shock association, rather than a deficit in hippocampal conjunctive processes (consolidation, pattern completion) that occur prior to shock on the training day. These findings illustrate the value of the CPFE for characterizing the separable memory processes that are impaired by neonatal alcohol exposure in this task.  相似文献   
4.
Despite growing interest in integrating people׳s daily mobility into contextual studies of social inequalities in health, the links between daily mobility and health inequalities remain inadequately conceptualised. This conceptual proposal anchors the relationship between daily mobility and contextual influences on social inequalities in health into the concept of mobility potential, which encompasses the opportunities and places individuals can choose (or are constrained) to access. Mobility potential is realized as actual mobility through agency. Being shaped by socially-patterned personal and geographic characteristics, mobility potential is unequally distributed across social groups. Social inequalities in realized mobility may thus result. We discuss pathways by which these may contribute to contextual influences on social inequalities in health. One pathway is reflected in disadvantaged groups encountering more fast-food outlets during their daily activities, which may relate to their higher risk of unhealthy eating. This proposal lays the bases for empirical research explicitly testing hypotheses regarding the contribution of daily mobility to social inequalities in health.  相似文献   
5.

Objective

To understand how recommendations for communication can be brought into alignment with clinical communication routines, we explored how doctors select communicative actions during consultations.

Methods

We conducted stimulated recall interviews with 15 GPs (general practitioners), asking them to comment on recordings of two consultations. The data analysis was based on the principles of grounded theory.

Results

A model describing how doctors select communicative actions during consultations was developed. This model illustrates how GPs constantly adapt their selection of communicative actions to their evaluation of the situation. These evaluations culminate in the selection of situation-specific goals. These multiple and often dynamic goals require constant revision and adaptation of communication strategies, leading to constant readjustments of the selection of communicative actions. When selecting consultation goals GPs weigh patients’ needs and preferences as well as the medical situation and its consequences.

Conclusions

GPs’ selection of communicative actions during consultations is situational and goal driven.

Practice implications

To help doctors develop communicative competence tailored to the specific situation of each consultation, holistic communication training courses, which pay attention to the selection of consultation goals and matching communication strategies besides training specific communication skills, seem preferable to current generic communication skills training.  相似文献   
6.
目的:通过调查笔录类文书证据收集及制作现状,分析语境在制作笔录类文书和收集证据中的作用,为加强证据的可靠性和可信度,完善证据链,提高执法水平提供建议和对策。方法:本研究拟以不同级别监督主体在制作笔录类文书不同阶段的语境表现为研究对象,选取吉林省九个市、州级卫生监督所中从事医疗卫生监督工作的监督员作为调查对象,运用SPSS13.0统计软件进行统计分析。结果:市级及县区级监督员笔录书写情况无统计学差异,且还原场景的比率较皆高于80%;市级及县区级监督员笔录语境把握情况有统计学差异(P>0.05),市级监督员对于语境的把握要好于县区级监督员;市级及县区级监督员证据收集难易程度和收集方式均有统计学差异(P>0.05),市级监督员较县区级监督员来讲,认为证据收集困难但遵循标准收集方式者居多。结论:要从监管部门、监督员、社会媒体以及群众四个方面,从法律普及、语境把握、业务培训、经验积累等多个角度提高证据的客观公正性,提高笔录类执法文书的总体质量。  相似文献   
7.
Understanding of human brain development has advanced rapidly as the field of developmental cognitive neuroscience (DCN) has matured into an established scientific discipline. Despite substantial progress, DCN lags behind other related disciplines in terms of diverse representation, standardized reporting requirements for socio-demographic characteristics of participants in pediatric neuroimaging studies, and use of intentional sampling strategies to more accurately represent the socio-demographic, ethnic, and racial composition of the populations from which participants are sampled. Additional efforts are needed to shift DCN towards a more inclusive field that facilitates the study of individual differences across a variety of cultural and contextual experiences. In this commentary, we outline and discuss barriers within our current scientific practice (e.g., research methods) and beliefs (i.e., what constitutes good science, good scientists, and good research questions) that contribute to under-representation and limited diversity within pediatric neuroimaging studies and propose strategies to overcome those barriers. We discuss strategies to address barriers at intrapersonal, interpersonal, community, systemic, and structural levels. Highlighting strength-based models of inclusion and recognition of the value of diversity in DCN research, along with acknowledgement of the support needed to diversify the field is critical for advancing understanding of neurodevelopment and reducing health inequities.  相似文献   
8.
Prenatal stress (PS) impairs memory function; however, it is not clear whether PS-induced memory deficits are specific to spatial memory, or whether memory is more generally compromised by PS. Here we sought to distinguish between these possibilities by assessing spatial, recognition and contextual memory functions in PS and nonstressed (NS) rodents. We also measured anxiety-related and social behaviors to determine whether our unpredictable PS paradigm generates a behavioral phenotype comparable to previous studies. Female Sprague-Dawley rats were exposed to daily random stress during the last gestational week and behavior tested in adulthood. In males but not females, PS decreased memory for novel objects and novel spatial locations, and facilitated memory for novel object/context pairings. In the elevated zero maze, PS increased anxiety-related behavior only in females. Social behaviors also varied with sex and PS condition. Females showed more anogenital sniffing regardless of stress condition. In contrast, prenatal stress eliminated a male-biased sex difference in nonspecific bodily sniffing by decreasing sniffing in males, and increasing sniffing in females. Finally, PS males but not females gained significantly more weight across adulthood than did NS controls. In summary, these data indicate that PS differentially impacts males and females resulting in sex-specific adult behavioral and bodily phenotypes.  相似文献   
9.
Three recent studies (Pearson, 2012 and Pearson et al., 2012) purported to test the revised dual representation theory of posttraumatic stress disorder (Brewin, Gregory, Lipton, & Burgess, 2010) by manipulating the amount of additional information accompanying traumatic stimulus materials and assessing the effect on subsequent intrusive memories. Here we point out that these studies involve a misunderstanding of the meaning of “contextual” within the theory, such that the manipulation would be unlikely to have had the intended effect and the results are ambiguous with respect to the theory. Past and future experimental tests of the theory are discussed.  相似文献   
10.
Neighbourhood socioeconomic status (SES) has been associated with numerous chronic diseases, yet little information exists on its association with lung cancer incidence. This outcome presents two key empirical challenges: a long latency period that requires study participants' residential histories and long-term neighbourhood characteristics; and adequate data on many risk factors to test hypothesized mediating pathways between neighbourhood SES and lung cancer incidence. Analysing data on urban participants of a large Canadian population-based lung cancer case-control study, we investigate three issues pertaining to these challenges. First, we examine whether there is an association between long-term neighbourhood SES, derived from 20 years of residential histories and five national censuses, and lung cancer incidence. Second, we determine how this long-term neighbourhood SES association changes when using neighbourhood SES measures based on different latency periods or at time of study entry. Third, we estimate the extent to which long-term neighbourhood SES is mediated by a range of individual-level smoking behaviours, other health behaviours, and environmental and occupational exposures. Results of hierarchical logistic regression models indicate significantly higher odds of lung cancer cases residing in the most compared to the least deprived quintile of the long-term neighbourhood SES index (OR: 1.46; 95% CI: 1.13–1.89) after adjustment for individual SES. This association remained significant (OR: 1.38; 1.01–1.88) after adjusting for smoking behaviour and other known and suspected lung cancer risk factors. Important differences were observed between long-term and study entry neighbourhood SES measures, with the latter attenuating effect estimates by over 50 percent. Smoking behaviour was the strongest partial mediating pathway of the long-term neighbourhood SES effect. This research is the first to examine the effects of long-term neighbourhood SES on lung cancer risk and more research is needed to further identify specific, modifiable pathways by which neighbourhood context may influence lung cancer risk.  相似文献   
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