全文获取类型
收费全文 | 13364篇 |
免费 | 907篇 |
国内免费 | 26篇 |
专业分类
耳鼻咽喉 | 83篇 |
儿科学 | 441篇 |
妇产科学 | 284篇 |
基础医学 | 1594篇 |
口腔科学 | 170篇 |
临床医学 | 1485篇 |
内科学 | 2342篇 |
皮肤病学 | 154篇 |
神经病学 | 1707篇 |
特种医学 | 613篇 |
外科学 | 2194篇 |
综合类 | 144篇 |
一般理论 | 22篇 |
预防医学 | 1275篇 |
眼科学 | 119篇 |
药学 | 928篇 |
中国医学 | 28篇 |
肿瘤学 | 714篇 |
出版年
2023年 | 71篇 |
2022年 | 106篇 |
2021年 | 279篇 |
2020年 | 176篇 |
2019年 | 294篇 |
2018年 | 334篇 |
2017年 | 244篇 |
2016年 | 276篇 |
2015年 | 276篇 |
2014年 | 466篇 |
2013年 | 643篇 |
2012年 | 983篇 |
2011年 | 1058篇 |
2010年 | 565篇 |
2009年 | 529篇 |
2008年 | 898篇 |
2007年 | 855篇 |
2006年 | 874篇 |
2005年 | 917篇 |
2004年 | 834篇 |
2003年 | 782篇 |
2002年 | 729篇 |
2001年 | 152篇 |
2000年 | 123篇 |
1999年 | 129篇 |
1998年 | 156篇 |
1997年 | 119篇 |
1996年 | 113篇 |
1995年 | 107篇 |
1994年 | 83篇 |
1993年 | 61篇 |
1992年 | 89篇 |
1991年 | 66篇 |
1990年 | 54篇 |
1989年 | 63篇 |
1988年 | 70篇 |
1987年 | 64篇 |
1986年 | 50篇 |
1985年 | 44篇 |
1984年 | 52篇 |
1983年 | 59篇 |
1982年 | 53篇 |
1981年 | 38篇 |
1980年 | 54篇 |
1979年 | 33篇 |
1978年 | 32篇 |
1977年 | 25篇 |
1976年 | 25篇 |
1975年 | 18篇 |
1971年 | 19篇 |
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
21.
W J Muir D M St Clair D H Blackwood H M Roxburgh I Marshall 《Psychological medicine》1992,22(3):573-580
Smooth pursuit eye movements to a sinusoidally moving target were recorded using the electro-oculogram in 49 subjects with bipolar disorder, 19 with major depressive disorder and 61 with definite schizophrenia, and compared with 145 normal controls. The signals were analysed in the frequency domain to yield a signal to noise ratio that is known to relate to accuracy of smooth pursuit. Smooth pursuit was found to be significantly poorer in schizophrenics than in bipolars, major depressed or controls. Eye-tracking performance was independent of the effects of neuroleptics, tricyclic antidepressants or lithium, and was not altered by the severity of depression in the affective psychoses. There was a small, but significant worsening of smooth pursuit with age in controls and schizophrenics, but this did not account for the group differences. The results support the view that among the major psychoses eye-tracking dysfunction is specific to schizophrenia. 相似文献
22.
23.
Robert M Bennett Jessie Jones Dennis C Turk I Jon Russell Lynne Matallana 《BMC musculoskeletal disorders》2007,8(1):27
Background
This study explored the feasibility of using an Internet survey of people with fibromyalgia (FM), with a view to providing information on demographics, sources of information, symptoms, functionality, perceived aggravating factors, perceived triggering events, health care utilization, management strategies, and medication use. 相似文献24.
25.
Reed Jon A.; Nador Roland G.; Spaulding David; Tani Yoichi; Cesarman Ethel; Knowles Daniel M. 《Blood》1998,91(10):3825-3832
26.
Genotypic selection of mutated DNA sequences using mismatch cleavage analysis, a possible basis for novel mutation assays 总被引:1,自引:1,他引:0
A novel technique for the selection of mutated DNA sequences,termed mismatch cleavage-polymerase chain reaction (MC-PCR),is proposed. The method is based on hybridizing genomic DNAwith a suitable probe, several 100 bp long. Mutated DNA sequenceswill form mismatched heteroduplexes which are cleaved by usingresolvases. Cleaved heteroduplexes are detected by ligationto an oligonucleotide adaptor and then amplified by using PCR.If practical, this technique would have considerable advantagesover the restriction site mutation (RSM) method. Failure toachieve cleavage efficiencies of close to 100% will not compromisesuccess. This is because positive signals (PCR amplification)arise from cleaved mutated sites and not, as in RSM, from DNAsequences resistant to cleavage by restriction endonucleases.Furthermore, the mutational target is much larger than in RSM.It would be possible to screen stretches of DNA several 100bp in length for mutations. Any mutation, independent of itslocation, could be identified. The usefulness of MC-PCR forthe genotypic selection of mutants will depend on the effectivenesswith which a small number of mismatched heteroduplexes can berecognized, cleaved and ligated.
1To whom correspondence should be addressed 相似文献
27.
BACKGROUND: Worldwide, fire-related burns are a major cause of unintentional injury, morbidity and mortality, with the majority of deaths occurring in developing countries. In the US, as in other countries, most fatal fires occur in the home. Effective prevention strategies for residential fires are, however, currently underutilized. The news media is one available communication channel to promote such strategies, and analyzing current news coverage is a first step towards incorporating media advocacy into injury prevention efforts related to residential fires. METHODS: Four daily newspapers circulating widely in Maryland were monitored for 1 year. Articles describing residential fires were coded for measures of prominence, content and frame. Analysis focused on measures of issue newsworthiness, reporting of causation and consequences of fires, and inclusion of public health context and conveyance of prevention messages. RESULTS: The data indicate that fires are newsworthy, with 374 relevant news articles in a 1-year period, 32% of which appear on the first page of a section. Coverage generally concerned recent local fire events. Most articles discussed the consequences of fires (88%), and identified a causal factor (58%). Only 36%, however, included prevention information, and less than one-quarter set residential fires in a public health context. CONCLUSION: The newsworthiness of residential fires provides a clear opportunity for widespread communication around injury prevention. Improving media advocacy will entail framing discussion of recent fire events in such a way as to support inclusion of prevention strategies and a public health context in news coverage. 相似文献
28.
Hyett Jon; Moscoso Gonzalo; Nicolaides Kypros 《Human reproduction (Oxford, England)》1995,10(11):3045-3048
Pathological examination of the heart and great vessels wasperformed in 61 specimens obtained after surgical terminationof pregnancy for psychosocial indications at 918 weeksof gestation. The aorta and pulmonary trunk were identifiedand external diameters were measured at the level of, and distalto the aortic valve and pulmonary valve, the level of the aorticisthmus and thoracic aorta, and the proximal and distal ductusarteriosus. All eight vessel diameters increased linearly withgestational age and the ratio of the diameter of the aorticisthmus to that of the aortic valve or the distal ductus arteriosusalso increased with gestation. Early pregnancy is characterizedby rapid growth of the fetal head and this may well be the consequenceof a preferential distribution of left ventricular output infavour of the head due to relative narrowing of the aortic isthmusat this gestation. 相似文献
29.
End-of-life (EOL) and palliative care education in medical school curricula stand at a crossroads. Consensus has emerged that these topics merit systematic instruction throughout medical school training, yet curricula all too often consist of sporadic lectures focused on bioethics instead of clinical skills. The medical student authors identified a deficit in their curriculum, and designed and implemented an EOL curriculum module for their colleagues. In early 2000 the authors surveyed senior medical students about their experiences with EOL and palliative education, identifying deficits in clinical training and recommendations for interventions. They then designed a case-based educational module to teach EOL communication skills to medical students commencing clinical training. Faculty with national and local experience with EOL and palliative care reviewed the curriculum. Twelve of these faculty were oriented to the curriculum and then taught it in pairs to groups of 12 to 16 medical students in 2000 and 2001. The curriculum develops skills, attitudes, and knowledge relevant for communicating bad news and establishing treatment options in the EOL setting by utilizing trigger videos, group discussion, role plays, and case discussions. Approximately 75% of the 86 eligible students attended the module in 2000 and 2001. Feedback has guided the curriculum's refinement by the medical student authors. In addition, a standardized patient exercise, introduced in 2001, allowed students to reinforce the skills learned during the module. 相似文献
30.