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Background   A growing interest exists in mechanisms involved in behaviour problems in children with mild intellectual disabilities and borderline intelligence (MID/BI). Social problem solving difficulties have been found to be an explanatory mechanism for aggressive behaviour in these children. However, recently a discrepancy was found between automatic and reflective responding in social situations. We hypothesise that low impulse control and aggressive social problem solving strategies together may explain mechanisms involved in aggressive behaviour by children with MID/BI.
Method   In a clinical sample of 130 children with MID/BI receiving intramural treatment, main, moderating and mediating effects of impulse control and aggressive response generation on aggressive behaviour were examined by conducting hierarchical linear multiple regression analyses.
Results   Independent main effects of both impulse control and aggressive response generation on aggressive behaviour were found. Results indicated that low impulse control and aggressive response generation each explain unique variance in aggressive behaviour.
Conclusions   As this study is the first that has shown both impulse control and aggressive response generation to be important predictors for aggressive behaviour in children with MID/BI, future research should further examine the nature of relations between low impulse control and social problem solving.  相似文献   
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This case report describes a male patient with trismus and generalized muscle weakness as the presenting symptom of disseminated malignancy. Trismus was caused by the presence of multiple small nests of undifferentiated tumor cells between muscle fibers of the masseter muscles as well as of other skeletal muscles. The diagnosis was suggested by increased uptake of 18-fluoro-deoxyglucose on positron emission tomography and subsequent ultrasound examination. The primary tumor was not found on autopsy. The patient was at increased risk for malignancy due to his renal transplantation 16 years before.  相似文献   
105.
Macroscopic particles (>500 μm), including marine snow, large migrating zooplankton, and their fast-sinking fecal pellets, represent primary vehicles of organic carbon flux from the surface to the deep sea. In contrast, freely suspended microscopic particles such as bacteria and protists do not sink, and they contribute the largest portion of metabolism in the upper ocean. In bathy- and abyssopelagic layers of the ocean (2,000–6,000 m), however, microscopic particles may not dominate oxygen consumption. In a section across the tropical Atlantic, we show that macroscopic particle peaks occurred frequently in the deep sea, whereas microscopic particles were barely detectable. In 10 of 17 deep-sea profiles (>2,000 m depth), macroscopic particle abundances were more strongly cross-correlated with oxygen deficits than microscopic particles, suggesting that biomass bound to large particles dominates overall deep-sea metabolism.  相似文献   
106.
In line with recent UK and Scottish policy imperatives, there is increasing pressure for the health visiting service to assume an enhanced role in improving public health. Although health visiting has so far maintained its unique position as a primarily preventive service within the UK health service, its distinctive contribution now appears under threat. The continuing absence of a comprehensive and integrated conceptual basis for practice has a negative impact on the profession’s ability to respond to current challenges. Establishing an integrative framework to conceptualise health visiting practice would enable more sensitive, focused and appropriate research, education and evaluation in relation to practice. Work in this area could thus usefully contribute to the future development of the service at a difficult time. Our paper aims to make such a contribution. In support of our conceptual aims, we draw on a study of health visiting practice undertaken within a large conurbation in central Scotland. The study used a mixed method, collaborative approach involving 12 audio‐recorded and observed health visitor–client interactions, semi‐structured interviews with the 12 HVs and 12 clients, examination of related documentation and workshops with the HV participants. We critically consider prevalent models of health visiting practice and describe the more integrative conceptual approach provided by Bronfenbrenner’s ecological, ‘person‐in‐context’ framework. The paper subsequently explores relationships between this framework and understandings of need demonstrated by health visitors who participated in our study. Current policy emphasises the need to focus on public health and social inclusion in order to improve health. However, if this policy is to be translated into practice, we must develop a more adequate understanding of how practitioners work effectively with families and individuals in a sensitive and context‐specific manner. Bronfenbrenner’s framework appears to offer a promising means of building on the current strengths of the health visiting service to further develop a ‘person‐in‐context’ approach to health improvement that is mindful of and responsive to multiple, inter‐related influences on health. We therefore recommend further research to directly test the utility of this framework.  相似文献   
107.

Introduction

Previous findings suggest that a delayed administration of phenylephrine replacing norepinephrine in septic shock patients causes a more pronounced hepatosplanchnic vasoconstriction as compared with norepinephrine. Nevertheless, a direct comparison between the two study drugs has not yet been performed. The aim of the present study was, therefore, to investigate the effects of a first-line therapy with either phenylephrine or norepinephrine on systemic and regional hemodynamics in patients with septic shock.

Methods

We performed a prospective, randomized, controlled trial in a multidisciplinary intensive care unit in a university hospital. We enrolled septic shock patients (n = 32) with a mean arterial pressure below 65 mmHg despite adequate volume resuscitation. Patients were randomly allocated to treatment with either norepinephrine or phenylephrine infusion (n = 16 each) titrated to achieve a mean arterial pressure between 65 and 75 mmHg. Data from right heart catheterization, a thermodye dilution catheter, gastric tonometry, acid-base homeostasis, as well as creatinine clearance and cardiac troponin were obtained at baseline and after 12 hours. Differences within and between groups were analyzed using a two-way analysis of variance for repeated measurements with group and time as factors. Time-independent variables were compared with one-way analysis of variance.

Results

No differences were found in any of the investigated parameters.

Conclusions

The present study suggests there are no differences in terms of cardiopulmonary performance, global oxygen transport, and regional hemodynamics when phenylephrine was administered instead of norepinephrine in the initial hemodynamic support of septic shock.

Trial registration

ClinicalTrial.gov NCT00639015  相似文献   
108.
BACKGROUND: Ropivacaine is primarily a local anesthetic, but it also acts as a vasoactive agent. Case reports have described a critical reduction in blood flow when higher concentrations of ropivacaine were used for peripheral-nerve blocks. One hypothesis is that local application of ropivacaine in tissues supplied by end arteries reduces tissue blood flow because of arterial vasoconstriction. METHODS: Rats were anesthetized by inhalation of isoflurane. The tail vessels were carefully dissected from the ventral side near the radix. Randomly, normal saline, prilocaine 0.5%, prilocaine 0.5% with epinephrine 1:200,000, ropivacaine 0.2%, ropivacaine 0.5%, or ropivacaine 0.75% was applied directly to the artery. Blood flow in the tail was continuously measured by use of laser Doppler flowmetry distal to the surgical site. Changes in temperature in the tail were detected by use of infrared thermography. RESULTS: Blood flow decreased after the application of ropivacaine at all concentrations in comparison with normal saline (P < .01 at t = 10 minutes, P < .001 at t = 20, 30, and 40 minutes). This effect was most pronounced at t = 30 minutes for ropivacaine 0.5% (with a 64.5% decrease in blood flow). Prilocaine 0.5% with epinephrine 1:200,000 reduced blood flow by up to 44.7% (t = 20 minutes, P < .001). In comparison with the placebo, the application of ropivacaine 0.5% and 0.75%, as well as prilocaine 0.5% with epinephrine 1:200,000, caused a significant reduction in tail temperature (P < .001 at t = 20, 30, and 40 minutes). No alteration in blood flow or temperature was seen after application of prilocaine 0.5%. CONCLUSIONS: The application of ropivacaine directly to a rat's tail artery diminished blood flow and lowered regional skin temperature. These effects were dose related. The use of ropivacaine at higher concentrations can, therefore, not be recommended if tissues supplied by end arteries might be affected.  相似文献   
109.
BACKGROUND AND OBJECTIVES: Thoracic epidural analgesia (TEA) is increasingly used for perioperative analgesia. If patients with TEA develop sepsis or systemic inflammatory response subsequent to extended surgery the question arises if it would be safe to continue TEA with its beneficial effects of improving gastrointestinal perfusion and augmenting tissue oxygenation. A major concern in this regard is hemodynamic instability that might ensue from TEA-induced vasodilation. The objective of the present study was to assess the effects of TEA on systemic and pulmonary hemodynamics in a sepsis model of hyperdynamic endotoxemia. METHODS: After a baseline measurement in healthy sheep (n = 14), Salmonella thyphosa endotoxin was continuously infused at a rate of 10 ngxkg(-1)xmin(-1) over 16 hours. The surviving animals (n = 12) were then randomly assigned to 1 of 2 study groups. In the treatment group (n = 6), continuous TEA was initiated with 0.1 mLxkg(-1) bupivacaine 0.125% and maintained with 0.1 mLxkg(-1)xh(-1). In the control group (n = 6) the same amount of isotonic sodium saline solution was injected at the same rate through the epidural catheter. RESULTS: In both experimental groups cardiac index increased and systemic vascular resistance decreased concurrently (each P < .05). Functional epidural blockade in the TEA group was confirmed by sustained suppression of the cutaneous (or panniculus) reflex. During the observational period of 6 hours neither systemic nor pulmonary circulatory variables were impaired by TEA. CONCLUSIONS: From a hemodynamic point of view, TEA presents as a safe treatment option in sepsis or systemic inflammatory response syndrome.  相似文献   
110.
AIMS OF THE STUDY: This paper uses the findings of a recent bibliometric analysis of published UK nursing research to ask whether the field is characterized by a fundamental split between two underlying areas of research interest. These can be termed 'endogenous' and 'exogenous'. The former term describes research which tends to be concerned with problems and issues to do with nursing as a profession; the latter is concerned with problems and issues centring around the nursing of patients. DESIGN/METHODS: Papers in the Wellcome Trust's Research Outputs Database (ROD), a database of UK biomedical research, were analysed. Nursing papers published between 1988 and 1995 numbered 1,845, just less than 1% of the total papers in the ROD. RESULTS/FINDINGS: Analysis of the subfield identified that nursing research was atypical of biomedical research as a whole in a number of ways. One difference was that usually in biomedical research there is a general correlation between numbers of funders acknowledged on a paper, numbers of authors, and esteem of the journal in which a paper appears. In nursing there was, if anything, a tendency for highly esteemed papers to have fewer authors and be less likely to have acknowledged funding. However, the apparently endogenous and exogenous papers have quite different characteristics. This paper explores this apparent difference and possible reasons for this difference and will briefly compare nursing research with some other newly emerging social and academic groups. CONCLUSIONS: Thinking of nursing research outputs in this way can provide insight into the existence of different reward systems influencing nurse researchers. However, it is impossible to draw too confident a differentiation without reading each individual paper and making judgements about whether they are 'endogenous' or 'exogenous', a practice generally beyond the scope of bibliometric practice.  相似文献   
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