全文获取类型
收费全文 | 3300篇 |
免费 | 207篇 |
国内免费 | 21篇 |
专业分类
耳鼻咽喉 | 18篇 |
儿科学 | 107篇 |
妇产科学 | 51篇 |
基础医学 | 559篇 |
口腔科学 | 58篇 |
临床医学 | 267篇 |
内科学 | 649篇 |
皮肤病学 | 53篇 |
神经病学 | 410篇 |
特种医学 | 48篇 |
外科学 | 435篇 |
综合类 | 24篇 |
一般理论 | 7篇 |
预防医学 | 390篇 |
眼科学 | 50篇 |
药学 | 146篇 |
中国医学 | 5篇 |
肿瘤学 | 251篇 |
出版年
2023年 | 53篇 |
2022年 | 85篇 |
2021年 | 130篇 |
2020年 | 78篇 |
2019年 | 96篇 |
2018年 | 99篇 |
2017年 | 74篇 |
2016年 | 84篇 |
2015年 | 116篇 |
2014年 | 145篇 |
2013年 | 195篇 |
2012年 | 252篇 |
2011年 | 285篇 |
2010年 | 148篇 |
2009年 | 140篇 |
2008年 | 189篇 |
2007年 | 190篇 |
2006年 | 221篇 |
2005年 | 208篇 |
2004年 | 192篇 |
2003年 | 154篇 |
2002年 | 133篇 |
2001年 | 13篇 |
2000年 | 3篇 |
1999年 | 14篇 |
1998年 | 24篇 |
1997年 | 14篇 |
1996年 | 18篇 |
1995年 | 15篇 |
1994年 | 16篇 |
1993年 | 14篇 |
1992年 | 9篇 |
1991年 | 7篇 |
1989年 | 4篇 |
1988年 | 4篇 |
1987年 | 5篇 |
1986年 | 5篇 |
1985年 | 4篇 |
1984年 | 8篇 |
1983年 | 5篇 |
1982年 | 6篇 |
1981年 | 3篇 |
1980年 | 3篇 |
1978年 | 6篇 |
1977年 | 4篇 |
1976年 | 4篇 |
1975年 | 3篇 |
1972年 | 3篇 |
1965年 | 3篇 |
1945年 | 4篇 |
排序方式: 共有3528条查询结果,搜索用时 15 毫秒
51.
Understanding which factors predict individual dissociative response during stressful situations is important to clarify the nature of dissociation and the mechanisms associated to its use as a coping strategy. The present study examined (1) whether experiential avoidance (EA), anxiety sensitivity (AS), depressive symptoms, and state anxiety concurrently predicted trait dissociation (TD)—absorption, amnesia, depersonalization, and total TD scores—and laboratory induced dissociation (LID); and (2) whether TD and catastrophizing predicted LID. We also examined whether catastrophizing mediated the relationships between both AS and depressive symptoms and LID. A total of 101 female undergraduate students participated in a cold pressor task, which significantly induced dissociation. Results of hierarchical regression analyses showed that AS at Time 1 (9 months before the experimental session), as well as depressive symptoms and catastrophizing at the time of the experiment (Time 2), predicted LID at Time 2. Depressive symptoms at Time 2 predicted total TD, absorption, and amnesia scores. AS at Time 1 and depressive symptoms at Time 2 predicted depersonalization. AS, depressive symptoms, and catastrophizing seem to facilitate the use of dissociative strategies by healthy individuals, even in response to non-traumatic but discomforting stress. 相似文献
52.
Long Kristin A. Chevalier Lydia Chu Andrea Guthrie Kate M. Kao Barbara Plante Wendy Lobato Debra 《Journal of autism and developmental disorders》2022,52(9):4100-4113
Journal of Autism and Developmental Disorders - Siblings describe positive and negative aspects of autism and often assume lifelong support roles. Less is known about cultural influences on sibling... 相似文献
53.
Schacher Sylvia Dock-Rust Daniela Döpker Sandra Dryden Frauke Fundel Beatrice Hempel Dorothea Hidas Christine Hottenbacher Lydia Marohl Ranka Milicevic Dagmar Möhring Fereschta Roßbach-Wilk Elisabeth Russig Julia Spitznagel Nadja Walder Julia Wrede Julia Ullrich Greta 《Notfall & Rettungsmedizin》2022,25(5):348-349
Notfall + Rettungsmedizin - 相似文献
54.
55.
The urine collecting duct system of the metanephric kidney develops by growth and branching morphogenesis of an unbranched progenitor tubule, the ureteric bud. Bud branching is mainly dichotomous and new branches form from existing branch tips, which are also the main sites of cell proliferation in the system. This behaviour, and the fact that some genes (e.g. Wnt11, Sox9) are expressed only in tips, suggests that tip cells are in a specific state of differentiation. In this report, we show that the lectin Dolichos biflorus agglutinin (DBA), hitherto regarded and used as a general marker of developing renal collecting ducts, binds to most of the duct system but does not bind to the very tips of growing branches. The zone avoided by DBA corresponds to the zone that expresses Wnt11, and the zone that shows enhanced cell proliferation. If branching of the ureteric bud of cultured embryonic kidneys is inhibited in organ culture, by blocking the kidney's endogenous glial cell-derived neurothrophic factor (GDNF)-based branch-promoting signals, the DBA-binding zone extends to the very end of the tip but is lost from there when branching is re-activated. Similarly, if excess GDNF is provided to growing kidneys, the DBA-free zone expands. DBA-staining status therefore appears to be a sensitive indicator of the morphogenetic activity of the collecting duct system. 相似文献
56.
Recent evidence suggests that the lateral habenular complex (LHb) is a source of negative reward signals in midbrain dopaminergic neurons. LHb activity, in turn, is modulated by locally released dopamine, which is largely derived from the ventral tegmental area (VTA) via the mesohabenular pathway. Unfortunately, the presumed importance of this modulation has not been appreciated so far, as its intensity had been largely underestimated in previous reports. Consequently, the present study used contemporary techniques to reexamine the origin of dopaminergic fibers to the LHb. For this purpose, the retrograde tract-tracer gold-coupled wheatgerm agglutinin was injected into the LHb of fourteen rats. Four of these animals providing the most representative information were selected for detailed analysis. In total, 343 retrogradely labeled neurons were detected in the VTAs of these animals. By far most of them were found in the anterior VTA, accumulating in its ventral paramedian fields. About 47% (162) of retrogradely labeled cells displayed tyrosine hydroxylase immunoreactivity, suggesting that almost half of the mesohabenular neurons are dopaminergic. In addition, our data suggest that also incerto-hypothalamic and periventricular neurons contribute dopaminergic terminals to the LHb. The majority of LHb neurons, however, does not project to the origin of the mesohabenular pathway in the anterior VTA. Consequently, there might be no closed VTA-LHb-VTA loop. Instead, our data are in line with the idea that the anterior VTA via its projection to the medial part of the LHb may modulate the information flow from the limbic forebrain to monoaminergic midbrain nuclei. 相似文献
57.
Setting priorities in global child health research investments: assessment of principles and practice 总被引:2,自引:2,他引:0 下载免费PDF全文
Rudan I Gibson J Kapiriri L Lansang MA Hyder AA Lawn J Darmstadt GL Cousens S Bhutta ZA Brown KH Hess SY Black M Gardner JM Webster J Carneiro I Chandramohan D Kosek M Lanata CF Tomlinson M Chopra M Ameratunga S Campbell H El Arifeen S Black RE;Child Health Nutrition Research Initiative 《Croatian medical journal》2007,48(5):595-604
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
58.
Setting priorities in global child health research investments: addressing values of stakeholders 下载免费PDF全文
Kapiriri L Tomlinson M Chopra M El Arifeen S Black RE Rudan I;Child Health Nutrition Research Initiative 《Croatian medical journal》2007,48(5):618-627
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59.
Miranda J. Delahoy Breanna Wodnik Lydia McAliley Gauthami Penakalapati Jenna Swarthout Matthew C. Freeman Karen Levy 《International journal of hygiene and environmental health》2018,221(4):661-676
Animals found in close proximity to humans in low-and middle-income countries (LMICs) harbor many pathogens capable of infecting humans, transmissible via their feces. Contact with animal feces poses a currently unquantified—though likely substantial—risk to human health. In LMIC settings, human exposure to animal feces may explain some of the limited success of recent water, sanitation, and hygiene interventions that have focused on limiting exposure to human excreta, with less attention to containing animal feces.We conducted a review to identify pathogens that may substantially contribute to the global burden of disease in humans through their spread in animal feces in the domestic environment in LMICs. Of the 65 potentially pathogenic organisms considered, 15 were deemed relevant, based on burden of disease and potential for zoonotic transmission. Of these, five were considered of highest concern based on a substantial burden of disease for which transmission in animal feces is potentially important: Campylobacter, non-typhoidal Salmonella (NTS), Lassa virus, Cryptosporidium, and Toxoplasma gondii. Most of these have a wide range of animal hosts, except Lassa virus, which is spread through the feces of rats indigenous to sub-Saharan Africa. Combined, these five pathogens cause close to one million deaths annually. More than half of these deaths are attributed to invasive NTS. We do not estimate an overall burden of disease from improperly managed animal feces in LMICs, because it is unknown what proportion of illnesses caused by these pathogens can be attributed to contact with animal feces.Typical water quantity, water quality, and handwashing interventions promoted in public health and development address transmission routes for both human and animal feces; however, sanitation interventions typically focus on containing human waste, often neglecting the residual burden of disease from pathogens transmitted via animal feces. This review compiles evidence on which pathogens may contribute to the burden of disease through transmission in animal feces; these data will help prioritize intervention types and regions that could most benefit from interventions aimed at reducing human contact with animal feces. 相似文献
60.