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1.
《Journal of pharmaceutical sciences》2019,108(11):3515-3520
Particle size analysis in the pharmaceutical industry has long been a source of debate regarding how best to define measurement accuracy; the degree to which the result of a measurement or calculation conforms to the true value. Defining a “true” value for the size of a particle can be challenging as the output of its measurement will differ because of variations in measurement approaches, instrumental differences and calculation methods. Consequently, for “real” particles, a universal “true” value does not exist and accuracy is therefore not a definable characteristic. Accordingly, precision is then a measure of the ability to reproducibly achieve a measurement of unknown relevance.This article proposes, in place of accuracy, a means to define the “appropriateness” of a measurement in line with the critical quality attributes (CQA) of the material being characterized. The decision as to whether the measurement is correct should involve a link to the CQA; that is, correlation should be demonstrated, without which the measured particle size cannot be defined as a critical material attribute.Correspondingly, methods should also be able to provide sufficient precision to demonstrate discrimination relating to variation in the CQA. The benefits and challenges of this approach are discussed. 相似文献
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《Vaccine》2020,38(45):7118-7128
IntroductionToward the Global Vaccine Action Plan 2020 goal, almost 90% of countries have established a National Immunization Technical Advisory Group (NITAG). However, little is known about NITAG's contributions to governance.MethodsIn 2017–2018, a two-step, qualitative retrospective study was conducted. Jordan (JO), Argentina (AR), and South Africa (SA) were selected owing to government-financed NITAGs from middle-income countries (MICs), geographic diversity, and a vaccine introduction with NITAG support. Country case studies were developed, collecting data through desk review and face-to-face key informant interviews (KIIs) from Ministry of Health (MoH) and NITAG. Case studies were analyzed together, to assess governance applying the European Observatory on Health Systems and Policies framework focusing on transparency, accountability, participation, integrity, and policy capacity (TAPIC).ResultsDocument review and 53 KII (22 AR, 20 SA, 11 JO) showed NITAGs played a pivotal role as advisors promoting a culture of evidence-informed policies. NITAGs strengthened governance, although practices varied among countries. Meetings were conducted behind-closed-doors, participation restricted to members, only in one country agendas, and recommendations were public (AR). To increase participation, policy capacity, and transparency, countries considered adding experts in communications, advocacy, and economics. AR and SA contemplated including community members. NITAGs functioned autonomously from the government, with no established internal or external monitoring or supervision. NITAG meeting minutes allowed the review of integrity, adherence to terms of reference, standard operating procedures, and conflict of interest (CoI). For the most part, NITAGs abided by their mandates. Significant issues were related to the level of MoH support and oversight of CoI declaration and documentation.ConclusionsSystematically implementing governance approaches could improve processes, better tailor policies, and implementation. The long-term survival and resilience of NITAGs in these countries showed they play a significant role in strengthening governance. Lessons learned could be useful to those promoting country-driven evidence-informed decision-making. 相似文献
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Polylactic acid (PLA) root replica in ridge maintenance after loss of a vertically fractured incisor
Abstract A periodontally affected tooth was prepared for a special treatment: Calcium hydroxide was introduced into the apical half of the root canal whereas its cervical part was filled with glass ionomer cement. The tooth was shortened subgingivally. After 6 weeks of epithelization over the residual root a palatal full-thickness flap was mobilized. The root was carefully extracted and chairside copy-milled from the biodegradable polylactic acid (PLA) material. The PLA-replica was implanted immediately into the socket and the flap was sutured. Aim of the treatment was to prevent the ridge collapse of the extraction area. Ridge height could be preserved during the 21 months of observation. With time the radiographic density of the cancellous bone increased in the implanted area, indicating that a PLA-replica is replaced by host's bone tissue. 相似文献
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医用低值材料采供管理的探讨 总被引:4,自引:2,他引:2
医疗消耗材料是医疗工作开展的基础,本文从医用低值消耗材料的计划制定、材料采购、库房库存结构、材料供应、成本核算等多方面探讨了如何对医疗消耗材料进行科学管理,这对医院的医疗发展和管理建设有着重要意义。 相似文献
9.
具有骨诱导活性的仿生骨基质材料的制备 总被引:9,自引:2,他引:7
目的将一种具有与骨形态发生蛋白2相似骨诱导活性的多肽p24共价结合于改性聚(丙交酯-co-乙交酯)基质材料上,以制备出具有骨诱导活性的仿生骨基质材料。方法将活性多肽p24通过交联剂共价结合于改性PLGA材料上作为实验组;以未加交联剂多肽溶液和材料简单混合反应为对照组,通过X射线光电子光谱法和扫描电镜检测交联情况;同时对两组材料进行钙离子吸附实验,初步评价其仿生矿化能力。结果XPS检测结果表明,实验组及对照组材料表面均已结合硫元素,两者含有硫元素含量分别为1.50%及0.09%;钙离子吸附实验结果表明,12h及24h时实验组材料的钙离子吸附量分别为0,126mg及0.231mg;12h及24h时对照组材料的钙离子吸附量分别为0.053、0.102mg。多肽交联之材料较混合之材料的钙离子吸附能力显著增强。结论在改性PLGA三嵌段材料上固定了BMP2活性多肽,为以后发挥其骨诱导活性修复骨缺损奠定了良好基础。 相似文献
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Industrial back belts and low back pain: Mechanisms and outcomes 总被引:1,自引:0,他引:1
The recent increased utilization of industrial back belts as personal protective equipment in the workplace has generated considerable controversy among occupational health and safety professionals in the United States. The purpose of this article is to review the literature regarding proposed mechanisms of action of these devices and studies related to outcome of belt utilization in the prevention of low back pain and disability in the workplace. At the present time, neither the suspected mechanisms of action nor the efficacy of these devices in the primary, secondary, and tertiary prevention of work-related low back pain has been adequately demonstrated in clinical trials. As a result, generally accepted guidelines regarding the safe use of belts in the occupational setting have not been established. Based on this review it is recommended that further well-controlled, prospective, randomized clinical trials are necessary to evaluate the effectiveness of these devices as personal protective equipment. During the interim, the decision to prescribe belts to employees in the workplace should be at the discretion of an adequately trained occupational health care provider. These devices should not be provided as an alternative to appropriate administrative and/or engineering controls. 相似文献