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51.
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   
52.
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   
53.
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   
54.

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   
55.
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   
56.
57.
International Urology and Nephrology - This study aimed at determining the feasibility of conducting a large-scale pragmatic effectiveness study on the implementation of multidisciplinary care...  相似文献   
58.
Non‐Uremic Calciphylaxis (NUC) is a rare condition that often manifests as intractable and painful integumentary wounds, afflicting patients with a high burden of co‐morbidity. The Endocannabinoid System (ECS) is a ubiquitous signalling system that is theorised to be dysregulated within wound beds and associated peri‐wound tissues. Preclinical research has shown that the dominant chemical classes derived from the cannabis plant, cannabinoids, terpenes, and flavonoids, interact with the integumentary ECS to promote wound closure and analgesia. This is a prospective open label cohort study involving two elderly Caucasian females with recalcitrant NUC leg ulcers of greater than 6 months duration. Topical Cannabis‐Based Medicines (TCBM) composed of cannabinoids, terpenes, and flavonoids were applied daily to both the wound bed and peri‐wound tissues until complete wound closure was achieved. Wounds were photographed regularly, and the digital images were subjected to planimetric analysis to objectively quantify the degree of granulation and epithelization. Analgesic utilisation, as a surrogate/proxy for pain scores, was also tracked. The cohort had a mean M3 multimorbidity index score of 3.31. Complete wound closure was achieved in a mean of 76.3 days. Additionally, no analgesics were required after a mean of 63 days. The treatments were well tolerated with no adverse reactions. The positive results demonstrated in very challenging wounds such as NUC, among highly complex patients, suggest that TCBM may have an even broader role within integumentary and wound management. This treatment paradigm warrants being trialled in other wound types and classes, and ultimately should be subjected to randomised controlled trials.  相似文献   
59.

Background

For breast-conserving surgery, the method of margin assessment that most frequently achieves negative margins without increasing the volume of tissue excised is uncertain. We examined our institutional experience with three different margin assessment methods used by six experienced breast surgeons.

Methods

Patients undergoing breast-conserving surgery for invasive carcinoma during July to December of a representative year during which each method was performed (perpendicular, 2003; tangential, 2004; cavity shave, 2011) were included. The effect of margin method on the positive margin rate at first excision and the total volume excised to achieve negative margins were evaluated by multivariable analysis, by surgeon, and by tumor size and presence of extensive intraductal component (EIC).

Results

A total of 555 patients were identified, as follows: perpendicular, 140; tangential, 124; and cavity shave, 291. The tangential method had a higher rate of positive margins at first excision than the perpendicular and cavity-shave methods (49, 15, 11 %, respectively; p < 0.0001). Median volumes to achieve negative margins were similar (55 ml perpendicular; 64 ml tangential; 62 ml cavity shave; p = 0.24). Four of six surgeons had the lowest rate of positive margins with the cavity-shave method, which was significant when compared to the tangential method (p < 0.0001) but not the perpendicular method (p = 0.37). The volume excised by the three methods varied by surgeon (p < 0.0001). The perpendicular method was optimal for T1 tumors without EIC; the cavity-shave method tended to be superior for T2–T3 tumors and/or EIC.

Conclusions

Although the cavity-shave method may decrease the rates of positive margins, its effect on volume is variable among surgeons and may result in an increase in the total volume excised for some surgeons and for small tumors without EIC.  相似文献   
60.
Negative affect appears frequently in rheumatic diseases, but studies about their importance and prevalence in systemic sclerosis patients are scarce, and the results are inconclusive separately. We conducted a comprehensive search on April 2013 of PubMed, Medline, and PsycINFO databases to identify original research studies published. A total of 48 studies were included in this systematic review. We found negative emotions have very high levels in these patients, compared to both healthy population other chronic rheumatic patients assessed with the same instruments and cutoffs. Depression has been, of the three negative emotions that we approach to in this review, the most widely studied in systemic sclerosis, followed by anxiety. Despite the fact that anger is a common emotion in these diseases is poorly studied. Methodologic issues limited the ability to draw strong conclusions from studies of predictors. Disease-specific symptoms (swollen joints, gastrointestinal and respiratory symptoms and digital ulcers) and factors related to physical appearance were associated with negative emotions. Interdisciplinary care and biopsychosocial approach would have a great benefit in the clinical management of these patients.  相似文献   
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