全文获取类型
收费全文 | 18002篇 |
免费 | 1353篇 |
国内免费 | 536篇 |
专业分类
耳鼻咽喉 | 70篇 |
儿科学 | 105篇 |
妇产科学 | 61篇 |
基础医学 | 935篇 |
口腔科学 | 1031篇 |
临床医学 | 1412篇 |
内科学 | 919篇 |
皮肤病学 | 75篇 |
神经病学 | 427篇 |
特种医学 | 548篇 |
外科学 | 1307篇 |
综合类 | 2383篇 |
一般理论 | 3篇 |
预防医学 | 4592篇 |
眼科学 | 102篇 |
药学 | 3785篇 |
23篇 | |
中国医学 | 1892篇 |
肿瘤学 | 221篇 |
出版年
2024年 | 28篇 |
2023年 | 292篇 |
2022年 | 418篇 |
2021年 | 818篇 |
2020年 | 790篇 |
2019年 | 582篇 |
2018年 | 580篇 |
2017年 | 594篇 |
2016年 | 593篇 |
2015年 | 646篇 |
2014年 | 1291篇 |
2013年 | 1735篇 |
2012年 | 1269篇 |
2011年 | 1352篇 |
2010年 | 1056篇 |
2009年 | 921篇 |
2008年 | 1202篇 |
2007年 | 997篇 |
2006年 | 830篇 |
2005年 | 656篇 |
2004年 | 492篇 |
2003年 | 421篇 |
2002年 | 349篇 |
2001年 | 333篇 |
2000年 | 258篇 |
1999年 | 191篇 |
1998年 | 134篇 |
1997年 | 148篇 |
1996年 | 112篇 |
1995年 | 86篇 |
1994年 | 97篇 |
1993年 | 100篇 |
1992年 | 81篇 |
1991年 | 54篇 |
1990年 | 51篇 |
1989年 | 44篇 |
1988年 | 49篇 |
1987年 | 45篇 |
1986年 | 32篇 |
1985年 | 38篇 |
1984年 | 20篇 |
1983年 | 17篇 |
1982年 | 16篇 |
1981年 | 16篇 |
1980年 | 17篇 |
1979年 | 10篇 |
1978年 | 5篇 |
1977年 | 8篇 |
1976年 | 5篇 |
1974年 | 3篇 |
排序方式: 共有10000条查询结果,搜索用时 16 毫秒
21.
Mehmet Varol Kadriye Benkli Ayşe T. Koparal Rakibe B. Bostancıoğlu 《Drug and chemical toxicology》2019,42(4):436-443
Drug design and discovery studies are important because of the prevalence of diseases without available medical cures. New anticancer agents are particularly urgent because of the high mortality rate associated with cancer. A series of mononuclear gold (III) and platinum (II) complexes based on boronated phenylalanine (BPA) were designed and synthesized using 4,4’-dimethyl-2,2’-dipyridyl (L1) or 1,10-phenanthroline-5,6-dion (L2) ligands to obtain promising anticancer drug candidates. Proton nuclear magnetic resonance, infrared, mass spectrometry, and elemental analyses were utilized for chemical characterizations. Cell viability, cancer cell colony formation, endothelial tube formation, and cytoskeleton staining assays were performed using A549 lung adenocarcinoma and human umbilical vein endothelial cells (HUVECs) to investigate preliminary pharmacological activities. L1-based platinum (II) complex (BPA-L1-Pt) was the most promising complex, and has similar activity with the approved chemotherapy drug cis-platinum. Half maximal inhibitory concentration values for BPA-L1-Pt were 9.15 µM on A549s and 16.61 µM on HUVECs; the values for cis-platinum were 5.24 µM on A549s and 23.14 µM on HUVECs. Consequently, further synthesis studies should be performed to boost the cancer cell selectivity feature of BPA by varying metal and ligand types. 相似文献
22.
23.
《Value in health》2020,23(10):1340-1348
ObjectivesWe applied principles for conducting economic evaluations of factorial trials to a trial-based economic evaluation of a cluster-randomized 2 × 2 × 2 factorial trial. We assessed the cost-effectiveness of atorvastatin, omega-3 fish oil, and an action-planning leaflet, alone and in combination, from a UK National Health Service perspective.MethodsThe Atorvastatin in Factorial With Omega EE90 Risk Reduction in Diabetes (AFORRD) Trial randomized 800 patients with type 2 diabetes to atorvastatin, omega-3, or their respective placebos and randomized general practices to receive a leaflet-based action-planning intervention designed to improve compliance or standard care. The trial was conducted at 59 UK general practices. Sixteen-week outcomes for each trial participant were extrapolated for 70 years using the United Kingdom Prospective Diabetes Study Outcomes Model v2.01. We analyzed the trial as a 2 × 2 factorial trial (ignoring interactions between action-planning leaflet and medication), as a 2 × 2 × 2 factorial trial (considering all interactions), and ignoring all interactions.ResultsWe observed several qualitative interactions for costs and quality-adjusted life-years (QALYs) that changed treatment rankings. However, different approaches to analyzing the factorial design did not change the conclusions. There was a ≥99% chance that atorvastatin is cost-effective and omega-3 is not, at a £20 000/QALY threshold.ConclusionsAtorvastatin monotherapy was the most cost-effective combination of the 3 trial interventions at a £20 000/QALY threshold. Omega-3 fish oil was not cost-effective, while there was insufficient evidence to draw firm conclusions about action planning. Recently-developed methods for analyzing factorial trials and combining parameter and sampling uncertainty were extended to estimate cost-effectiveness acceptability curves within a 2x2x2 factorial design with model-based extrapolation. 相似文献
24.
医疗设备维修管理之团队建设 总被引:3,自引:3,他引:0
通过我院设备科设备维修队伍的团队建设,说明团队建设在设备维修管理中的重要性。 相似文献
25.
加强医疗仪器设备管理提高医疗仪器设备使用效益 总被引:1,自引:0,他引:1
加强医疗设备管理,提高设备使用效益,制定合理的计划,正确选购设备,为医院提供品种、性能、精度适当的技术装备。 相似文献
26.
James H. McKerrow 《Perspectives in Drug Discovery and Design》1995,2(3):437-444
Summary Papain family cysteine proteases function primarily intracellularly in higher eukaryotes, but are often extracellular proteases in protozoan helminths. The utility of this class of enzymes is reflected in the diversity of functions they perform in both parasite life cycles and the pathogenesis of parasitic diseases. Examples include secretion of proteases into the gut of parasitic worms for hemoglobin degradation, release from the surface of nematodes to degrade cuticular proteins during molting, and facilitating excystment of protozoa. 相似文献
27.
J.I. Smedberg E. Lothigius I. Bodin A. Frykholm K. Nilner 《Clinical oral implants research》1993,4(1):39-46
In order to satisfy the need to restore the aesthetics, phonetics and comfort and to facilitate optimal hygiene procedures, 20 edentulous patients were treated with a new concept of overdenture therapy on implants ad modum Brånemark. After 24±3.5 months the patients were re‐examined. They were asked to answer a questionnaire and use a Visual Analogue Scale (VAS) to give their opinion on the prosthetic treatment. The results indicate that an implant‐retained overdenture in the maxilla with this design can satisfy the patients needs in aesthetics, phonetics and comfort and can 1 facilitate oral hygiene measures. 相似文献
28.
Regulations evolve and risks management becomes one of the biomedical engineers' preoccupations. Thus, risks are various, and consequently it is difficult to identify, to manage and to bring them under control. Furthermore, regulations exist for sectors like healthcare technology monitoring, but it is not the same thing for instance for the risks linked to the maintenance. Thus regulation in the sector of maintenance evolves and the decree of the 1st July law of health safety is going to modify the biomedical environment. The goal of this work is to study the tools and the methods of risks management that have been used for several years in the industrial field and to use them for some biomedical equipment like monitors or IV pumps. These methods adapted to these equipment will allow us to determine some appropriate rules of maintenance. 相似文献
29.
Objective: Considering the growing use of cellular phones and the fast appearance of new phone models, the electromagnetic interference of currently popular cellular phones on electronic medical equipment was tested. Methods: Three Personal Communication System cellular phones were put at different distances from multiple electronic medical devices, the interference effect was observed and the electromagnetic field strength measured with a spectrum analyser. Results: Only two small pieces of equipment, the CO2 airway adapter and the haemoglucostix meter were affected and then only when the phone was in very close proximity. Conclusion: Compared to the results of our study in 1997 testing Global System for Mobile Communication phones, the Personal Communication System phones generated less electromagnetic interference. However a much larger scaled study and an accurate international electromagnetic interference standard are recommended before any change in the current restrictive hospital policy on mobile phone usage could be recommended. 相似文献
30.
Many important pharmaceutical agents, including vancomycin, bleomycin, cyclosporin, and several antibiotics, are produced by non‐ribosomal peptide synthetase (NRPS) enzymes in microorganisms. The NRPS pathway produces an extensive library of products using multienzyme complexes acting in an assembly‐line fashion. Engineering an NRPS system to produce an even greater variety of products, some of which may also have beneficial therapeutic value, would be an enormous advantage. Several approaches have been successful in generating novel NRPS products: mutational biosynthesis during which nonnatural substrates are fed to an organism; domain and module swapping between different species to generate hybrid enzymes; and rational site‐directed mutagenesis, based either on phylogeny or computational prediction, intended to switch substrate specificity and produce altered products. This review will highlight the progress in these areas and describe research in the future that will extend the capacity for re‐engineering NRPS systems. Drug Dev. Res. 66:9–18, 2006. © 2006 Wiley‐Liss, Inc. 相似文献