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101.
Hurricane Katrina was the most devastating natural disaster to hit the United States in the past 75 years. The authors conducted interviews of 810 persons who were representative of adult residents living in the 23 southernmost counties of Mississippi before Hurricane Katrina. The prevalence of posttraumatic stress disorder (PTSD) since Hurricane Katrina was 22.5%. The determinants of PTSD were female gender, experience of hurricane-related financial loss, postdisaster stressors, low social support, and postdisaster traumatic events. Kaplan-Meier survival curves suggest that exposure to both hurricane-related traumatic events and to financial and social stressors influenced the duration of PTSD symptoms. Postdisaster interventions that aim to improve manipulable stressors after these events may influence the onset and course of PTSD.  相似文献   
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OBJECTIVES: We examined variability in disease rates to gain understanding of the complex interactions between contextual socioeconomic factors and health. METHODS: We compared mortality rates between New York and California counties in the lowest and highest quartiles of socioeconomic status (SES), assessed rate variability between counties for various outcomes, and examined correlations between outcomes' sensitivity to SES and their variability. RESULTS: Outcomes with mortality rates that differed most by county SES were among those whose variability across counties was high (e.g., AIDS, homicide, cirrhosis). Lower-SES counties manifested greater variability among outcome measures. CONCLUSIONS: Differences in health outcome variability reflect differences in SES impact on health. Health variability at the ecological level might reflect the impact of stressors on vulnerable populations.  相似文献   
104.
Ethnic minority groups are growing as a proportion of the British population. Although disparate, literature suggests inequalities in obesity risk within and among ethnic minority groups relative to Caucasians in the UK. We summarize and appraise the existing peer‐reviewed literature about the prevalence and determinants of obesity among ethnic minority groups relative to Caucasians among children and adults in the UK. There was no consensus about obesity prevalence relative to Caucasians among South Asian or Black children or among South Asian adults relative to Caucasians. Black adults generally had higher risk for obesity than Caucasians. Both Chinese children and adults had lower risk for obesity than Caucasians. Few studies have considered differences in the aetiology of obesity by ethnicity. The lack of consensus regarding obesity risk among large ethnic minority groups relative to Caucasians in the UK, and the paucity of studies concerned with differences in obesity aetiology by ethnicity warrant further research in this area. Certain obesity metrics may bias obesity prevalence among particular ethnic groups relative to Caucasians. We summarize key methodological limitations to the current literature and suggest avenues for future research.  相似文献   
105.
BackgroundDevelopmental care consists of a range of clinical, infant-focused, and family-focused interventions designed to modify the neonatal intensive care environment and caregiving practices to reduce stressors on the developing brain. Since the inception of developmental care in the early 1980s, it has been recommended and adopted globally as a component of routine practice for neonatal care. Despite its application for almost 40 y, little is known of the attitude of neonatal nurses in Australia towards the intervention.Aims and objectivesThe objective of this study was to establish Australian neonatal nurse perceptions of developmental care and explore associations between developmental care education levels of the nurses and personal beliefs in the application of developmental care.DesignThis involves a cross-sectional survey design.MethodsAn online questionnaire was completed by 171 neonatal nurses. Participants were members of the Australian College of Neonatal Nursing (n = 783). Covariate associations between key components of developmental care and respondents' geographical location, place of employment, professional qualifications, and developmental care education level were analysed. The reporting of this study is in accordance with the Enhancing the Quality and Transparency of Health Research Checklist for Reporting Results of Internet E-Surveys.ResultsDifferences were observed between groups for geographical location, place of employment, and professional qualification level. Rural nurses were less likely to support the provision of skin-to-skin care (odds ratio [OR]: 0.6, 95% confidence interval [CI]: 0.2–1.8) than nurses in a metropolitsan unit. Nurses working in a neonatal intensive care unit and nurses with postgraduate qualifications were more likely to support parental involvement in care ([OR: 2.3, 95% CI: 0.9–6.2] and [OR: 2.1, 95% CI: 0.6–7.4], respectively). Rural respondents were more likely to have attended off-site education (OR: 3.6, 95% CI: 1.3–9.9) than metropolitan respondents.ConclusionThe application of developmental care in Australia may be influenced by inadequate resources and inequitable access to educational resources, and similar challenges have been reported in other countries. Overcoming the challenges requires a focused education strategy and support within and beyond the neonatal intensive care unit.  相似文献   
106.
Adult neurogenesis continues throughout life in the mammalian hippocampus. The precise function of the adult generated neurons remains uncertain although there is growing evidence that they are involved in hippocampus‐dependent learning and memory. Training rats on a hidden platform version of the Morris water task has been shown to increase or decrease the survival of newly produced cells in the dentate gyrus (DG) compared to training on a visible platform version. Here we investigated whether the difficulty of the task is related to the degree or direction of the change in neurogenesis. We trained rats on either a visible platform version of the Morris water task or one of three different hidden platform paradigms: four training trials per session version, two training trials per session, and reduced‐cue (a version in which the majority of the distal cues were removed from the room). BrdU was administered 6 days prior to training and rats were perfused 24 h after the last training session. As expected, training on the four trial hidden platform version increased cell survival compared to training on the visible platform version. However, training on the more difficult reduced‐cue hidden platform version resulted in a decrease in cell survival. Rats that received fewer trials per session did not differ in terms of cell survival in comparison to rats trained on the visible platform version. These findings demonstrate that altering the difficulty of the spatial task has an impact on the corresponding change in cell survival. The lack of obvious distal cues likely changed the strategy used by the rats to determine the location of the platform and resulted in a decrease, instead of an increase in cell survival in the hippocampus. In conclusion, different types of hippocampus‐dependent learning can differentially impact cell survival. © 2009 Wiley‐Liss, Inc.  相似文献   
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Identification of outpatients with high platelet reactivity (HPR) on antiplatelet treatment is an unmet need. The present study was conducted in healthy individuals (n = 50) and in outpatients with coronary artery disease (CAD) at a distance from the acute ischemic episode (aspirin group, n = 71; aspirin/clopidogrel group, n = 106). We studied the feasibility and the precision of whole blood multiple electrode aggregometry (MEA) after triggering platelet aggregation by arachidonic acid or adenosine diphospate (ADP). The MEA can be performed on whole blood within 2 hours after sample venipuncture. The threshold for the diagnosis of HPR is situated at 55 and 50 U for the arachidonic acid and ADP test, respectively. Frequency of HPR was 7% and 20% in aspirin and aspirin/clopidogrel groups, respectively. In 3.8% of patients in aspirin/clopidogrel group, combined HPR on aspirin and clopidogrel was found. In outpatients with CAD, use of MEA is feasible for the diagnosis of HPR.  相似文献   
109.
110.

Objectives

This study applied advanced 4-dimensional flow magnetic resonance imaging processing to assess differences in aortic flow dynamics after valve sparing root replacement, with and without reconstruction of the Valsalva sinuses.

Methods

We enrolled patients after valve sparing root replacement with a straight tubular prosthesis (n = 10) or with a prosthesis with Valsalva neosinuses (n = 10); age-matched subjects without cardiovascular diseases served as controls (n = 10). 4-Dimensional flow magnetic resonance imaging acquisitions were performed on a 3.0T magnetic resonance imaging unit. In-house processing was used to segment the aortic lumen and extract the volumetric 4-dimensional flow velocity field. Velocity flow streamlines were computed to compare the amount of rotational flow and wall shear stress. Occurrence of abnormal wall shear stress (WSS) was estimated within the descending aorta of each surgical group.

Results

Physiologic-like sinus vortices were visible in the aortic root when using the prosthesis with neosinuses, whereas straight tubular graft revealed localized intrados malrotations (P = .003 for organized vortical structures vs neosinuses graft and P < .001 vs control). In the ascending aorta, recreation of the sinuses resulted in significantly lower velocity and WSS than in the straight tubular graft (P < .001) and controls (P < .001), these alterations were attenuated in the mid-descending aorta. Incidence of abnormal WSS was markedly higher in the straight tube grafts than neosinus of Valsalva grafts.

Conclusions

Re-creation of the sinuses of Valsalva during valve-sparing root replacement is associated with more physiologic flow and significantly lower WSS in the aortic root. Lower WSSs in the distal thoracic aorta is a novel finding with potential implications on distal aortic remodeling.  相似文献   
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