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61.
62.
The relationship between research evidence, policy and implementation is complex throughout the world, but where resources are scarce (especially in developing countries) there is a need to ensure rational implementation. With reference to a study on which we work, we show how the simple act of conducting research where resources are lacking affects implementability. We discuss five key issues with which researchers must engage if they wish to affect policy and implementation: evidence is not the only criterion by which implementation decisions are made, implementation decisions are often political rather than health-oriented in the narrow sense, there is often a difference in time scale between research enterprises and policy implementation, moving from research to the ‘real world’ requires engagement with existing organisational systems, and we need to be able to tell the difference between changes in rhetoric and changes in the real world. The broad international context of funding and the scientific community also affect how researchers work in developing countries. We suggest that engagement with these apparently ‘non-scientific’ concerns is essential to the work of researchers.  相似文献   
63.
Achalasia is a rare disease of the esophagus that has an unknown etiology. Genetic, infectious, and autoimmune mechanisms have each been proposed. Autoimmune diseases often occur in association with one another, either within a single individual or in a family. There have been separate case reports of patients with both achalasia and one or more autoimmune diseases, but no study has yet determined the prevalence of autoimmune diseases in the achalasia population. This paper aims to compare the prevalence of autoimmune disease in patients with esophageal achalasia to the general population. We retrospectively reviewed the charts of 193 achalasia patients who received treatment at Toronto's University Health Network between January 2000 and May 2010 to identify other autoimmune diseases and a number of control conditions. We determined the general population prevalence of autoimmune diseases from published epidemiological studies. The achalasia sample was, on average, 10–15 years older and had slightly more men than the control populations. Compared to the general population, patients with achalasia were 5.4 times more likely to have type I diabetes mellitus (95% confidence interval [CI] 1.5–19), 8.5 times as likely to have hypothyroidism (95% CI 5.0–14), 37 times as likely to have Sjögren's syndrome (95% CI 1.9–205), 43 times as likely to have systemic lupus erythematosus (95% CI 12–154), and 259 times as likely to have uveitis (95% CI 13–1438). Overall, patients with achalasia were 3.6 times more likely to suffer from any autoimmune condition (95% CI 2.5–5.3). Our findings are consistent with the impression that achalasia's etiology has an autoimmune component. Further research is needed to more conclusively define achalasia as an autoimmune disease.  相似文献   
64.
65.

Summary

Androgen deprivation therapy in 80 men was associated with declines in bone mineral density (BMD), which were greatest in the first year, and in the lumbar spine compared to controls. Vitamin D use was associated with improved BMD in the lumbar spine and in the first year.

Introduction

Decreased BMD is a common side effect of androgen deprivation therapy (ADT), leading to increased risk of fractures. Although loss of BMD appears to be greatest within the first year of starting ADT, there are few long-term studies of change in BMD, and risk factors for bone loss are not well-characterized.

Methods

Men aged 50+ with nonmetastatic prostate cancer starting continuous ADT were enrolled in a prospective longitudinal study. BMD was determined by dual-energy x-ray absorptiometry at baseline and yearly for 3 years. Matched controls were men with prostate cancer not receiving ADT. Multivariable regression analysis examined predictors of BMD loss.

Results

Eighty ADT users and 80 controls were enrolled (mean age 69 years); 52.5 % had osteopenia and 8.1 % had osteoporosis at baseline. After 1 year, in adjusted models, ADT was associated with significant losses in lumbar spine BMD compared to controls (?2.57 %, p?=?0.006), with a trend towards greater declines at the total hip (p?=?0.09). BMD changes in years 2 and 3 were much smaller and not statistically different from controls. Use of vitamin D but not calcium was associated with improved BMD in the lumbar spine in year 1 (+6.19 %, p?<?0.001) with smaller nonsignificant increases at other sites (+0.86 % femoral neck, +0.86 % total hip, p?>?0.10) primarily in the first year.

Conclusions

Loss of BMD associated with ADT is greatest at the lumbar spine and in the first year. Vitamin D but not calcium may be protective particularly in the first year of ADT use.  相似文献   
66.

Background

The optimal surgical management of small nonfunctional pancreatic neuroendocrine tumors (NF-PNETs) remains controversial. We sought to identify (1) clinicopathologic factors associated with survival in NF-PNETs and (2) preoperative tumor characteristics that can be used to determine which lesions require resection and lymph node (LN) harvest.

Methods

The records of all 116 patients who underwent resection for NF-PNETs between 1989 and 2012 were reviewed retrospectively. Preoperative factors, operative data, pathology, surgical morbidity, and survival were analyzed.

Results

The overall 5- and 10-year survival rates were 83.9 and 72.8 %, respectively. Negative LNs (p?=?0.005), G1 or G2 histology (p?=?0.033), and age <60 years (p?=?0.002) correlated with better survival on multivariate analysis. The 10-year survival rate was 86.6 % for LN-negative patients (n?=?73) and 34.1 % for LN-positive patients (n?=?32). Tumor size ≥2 cm on preoperative imaging predicted nodal positivity with a sensitivity of 93.8 %. Positive LNs were found in 38.5 % of tumors ≥2 cm compared to only 7.4 % of tumors <2 cm.

Conclusions

LN status, a marker of systemic disease, was a highly significant predictor of survival in this series. Tumor size on preoperative imaging was predictive of nodal disease. Thus, it is reasonable to consider parenchyma-sparing resection or even close observation for NF-PNETs <2 cm.  相似文献   
67.
68.
This article reviews theoretical and practical approaches for setting priorities in global child health research investments. It also provides an overview of previous attempts to develop appropriate tools and methodologies to define priorities in health research investments. A brief review of the most important theoretical concepts that should govern priority setting processes is undertaken, showing how different perspectives, such as medical, economical, legal, ethical, social, political, rational, philosophical, stakeholder driven, and others will necessarily conflict each other in determining priorities. We specially address present research agenda in global child health today and how it relates to United Nation's (UN) Millennium Development Goal 4, which is to reduce child mortality by two-thirds between 1990 and 2015. The outcomes of these former approaches are evaluated and their benefits and shortcomings presented. The case for a new methodology for setting priorities in health research investments is presented, as proposed by Child Health and Nutrition Research Initiative, and a need for its implementation in global child health is outlined. A transdisciplinary approach is needed to address all the perspectives from which investments into health research can be seen as priorities. This prioritization requires a process that is transparent, systematic, and that would take into account many perspectives and build on advantages of previous approaches.  相似文献   
69.

Aim

To identify main groups of stakeholders in the process of health research priority setting and propose strategies for addressing their systems of values.

Methods

In three separate exercises that took place between March and June 2006 we interviewed three different groups of stakeholders: 1) members of the global research priority setting network; 2) a diverse group of national-level stakeholders from South Africa; and 3) participants at the conference related to international child health held in Washington, DC, USA. Each of the groups was administered different version of the questionnaire in which they were asked to set weights to criteria (and also minimum required thresholds, where applicable) that were a priori defined as relevant to health research priority setting by the consultants of the Child Health and Nutrition Research initiative (CHNRI).

Results

At the global level, the wide and diverse group of respondents placed the greatest importance (weight) to the criterion of maximum potential for disease burden reduction, while the most stringent threshold was placed on the criterion of answerability in an ethical way. Among the stakeholders’ representatives attending the international conference, the criterion of deliverability, answerability, and sustainability of health research results was proposed as the most important one. At the national level in South Africa, the greatest weight was placed on the criterion addressing the predicted impact on equity of the proposed health research.

Conclusions

Involving a large group of stakeholders when setting priorities in health research investments is important because the criteria of relevance to scientists and technical experts, whose knowledge and technical expertise is usually central to the process, may not be appropriate to specific contexts and in accordance with the views and values of those who invest in health research, those who benefit from it, or wider society as a whole.When decisions on investments in health research are made, the term “stakeholders” refers to all individuals and/or groups who have interest in prioritization of those investments. The stakeholders will therefore comprise a large and highly heterogeneous group. Some apparent examples may include research funding agencies (eg, governmental agencies, private organizations, public-private partnerships, international and regional organizations, and taxpayers of a certain region), direct recipients of the funding (eg, researchers and research institutions), beneficiaries of the research (eg, policy makers and the general population of a country), and any other group with interest in prioritization process (eg, advocacy groups, journalists and media, lawyers, economists, experts in ethics, and many others).Two fundamental characteristics of any acceptable and successful priority setting process are legitimacy and fairness (1). In order to ensure the legitimacy and fairness of the priority setting decisions in health research investments, involvement of a wide range of stakeholders (and/or eliciting their values) is needed. Unfortunately, health research priorities are presently mainly driven by technical experts (2-5). The results of prioritization are therefore in danger of being mostly influenced by their personal views, with minimal input from representatives from the wider community who also may have interest in the process but lack technical expertise. Since the values and criteria important to scientists and technical experts may vary remarkably from those of other relevant stakeholders (6-8), the relevance of eliciting wider stakeholders’ input is increasingly being acknowledged (9-11). However, the main challenge is to develop a systematic, flexible, and repeatable strategy on how this can be achieved in different contexts.The literature on priority setting for health interventions identifies two main strategies: 1) stakeholders’ values may impact decisions through procedural processes (by having access to the decisions and the rationales behind the decisions, and by having the authority to deliberate on the decisions and influence the final outcome); 2) stakeholders’ values can be directly elicited using quantitative methods (through surveys where respondents rank, weigh, or rate their values) and qualitative methods (involving individual interviews, Delphi technique, complaints procedures or group discussions, concept mapping, citizen’s jury, and public meetings) (12). The main challenges in those attempts have mainly been the lack of capacity for some stakeholders to engage in meaningful deliberations (13) and how to practically incorporate the elicited stakeholders’ values in decision-making (12,14). This paper presents our suggestions and experiences on how the values and interests of large and diverse group of stakeholders could still be incorporated in decisions on health research investment priorities. We specified thresholds and weights needed to address stakeholders’ values within CHNRI methodology using three different versions of a questionnaire. We aimed to assess stakeholders’ values for priority setting in global health research investments. We tested questionnaires that presented different levels of complexity and detail of the questions that stakeholders’ representatives would be asked. We also aimed to evaluate different strategies of turning their responses into numerical thresholds and weights.  相似文献   
70.
BACKGROUND: Affective disorder, once seen as rare in sub-Saharan Africa, is now viewed as more common. There are however challenges in assessing rates of depression, exploring manifestations of depression, and understanding risk factors for depression, especially those related to gender. AIM: To identify key themes and new directions for research on affective disorder in sub-Saharan Africa, with particular reference to gender issues. METHODS: Interpretive review of selected literature, and theoretical analysis. RESULTS: There are gender differences in manifestations and rates of depression in sub-Saharan Africa, and there are forms of presentation (largely somatic, based on interpersonal relationships, or spiritual in nature) which may obscure the detection of depression. Studies are consistent however that when depressive symptoms are sought and are present, these are reasonably easy to elicit. LIMITATIONS: This was not a systematic review, and the substantial grey literature from sub-Saharan Africa was not reviewed. For many countries, there are no data available. CONCLUSIONS: Affective disorder, when properly sought for through both qualitative and quantitative methods, has been found to be common in sub-Saharan Africa. There is a paucity of research on interventions with affective disorder in this region.  相似文献   
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