全文获取类型
收费全文 | 2462篇 |
免费 | 260篇 |
国内免费 | 3篇 |
专业分类
耳鼻咽喉 | 16篇 |
儿科学 | 71篇 |
妇产科学 | 10篇 |
基础医学 | 391篇 |
口腔科学 | 85篇 |
临床医学 | 176篇 |
内科学 | 310篇 |
皮肤病学 | 108篇 |
神经病学 | 500篇 |
特种医学 | 66篇 |
外科学 | 290篇 |
综合类 | 52篇 |
预防医学 | 169篇 |
眼科学 | 66篇 |
药学 | 127篇 |
肿瘤学 | 288篇 |
出版年
2022年 | 18篇 |
2021年 | 41篇 |
2020年 | 36篇 |
2019年 | 47篇 |
2018年 | 42篇 |
2017年 | 29篇 |
2016年 | 43篇 |
2015年 | 42篇 |
2014年 | 45篇 |
2013年 | 68篇 |
2012年 | 107篇 |
2011年 | 90篇 |
2010年 | 74篇 |
2009年 | 66篇 |
2008年 | 102篇 |
2007年 | 83篇 |
2006年 | 100篇 |
2005年 | 103篇 |
2004年 | 93篇 |
2003年 | 88篇 |
2002年 | 92篇 |
2001年 | 84篇 |
2000年 | 78篇 |
1999年 | 84篇 |
1998年 | 52篇 |
1997年 | 25篇 |
1996年 | 29篇 |
1995年 | 31篇 |
1994年 | 21篇 |
1993年 | 28篇 |
1992年 | 90篇 |
1991年 | 73篇 |
1990年 | 59篇 |
1989年 | 58篇 |
1988年 | 61篇 |
1987年 | 50篇 |
1986年 | 36篇 |
1985年 | 49篇 |
1984年 | 31篇 |
1983年 | 32篇 |
1981年 | 19篇 |
1980年 | 20篇 |
1979年 | 22篇 |
1977年 | 19篇 |
1976年 | 17篇 |
1975年 | 19篇 |
1974年 | 17篇 |
1972年 | 24篇 |
1971年 | 20篇 |
1970年 | 18篇 |
排序方式: 共有2725条查询结果,搜索用时 0 毫秒
41.
M Price C Specht R E Boudreau D E Shaw D L Weller 《Molecular and biochemical parasitology》1983,8(2):137-143
The ribosomes of Entamoeba invadens trophozoites have sedimentation coefficients of 77, 53 and 36 S. Most of the ribosomal proteins are basic and their one- and two-dimensional electrophoretic patterns differ from the corresponding patterns of Escherichia coli and Saccharomyces cerevisiae. Two dozen bands were observed in the 10 000 to 100 000 molecular weight range following sodium dodecylsulfate-gel electrophoresis of amoebal ribosomal proteins. Long, thin pronase-sensitive structures were seen in electron micrographs of E. invadens ribosomal preparations. 相似文献
42.
The aims of this study were to identify the immunodominant protein antigens of Candida albicans in patients with superficial infections of the oral and vaginal mucosa. Cytoplasmic protein extract from C. albicans was analyzed by the immunoblot technique using sera from 20 patients with chronic atrophic oral candidosis, from 8 patients with vulvovaginal candidosis, and from 20 control subjects. A significantly greater proportion of patient sera reacted with the 65- and 32-kDa antigens when compared with sera from controls (P less than 0.001). Sera from patients also reacted more often with 38- and 29-kDa antigens (P less than 0.05), while sera from both patients and controls reacted with the 47-kDa antigen. The identified 65-, 38-, 32-, and 29-kDa antigens may be of importance for the development and also for the recurrence of superficial candidosis of the oral and/or vaginal mucosa. 相似文献
43.
P.D. Grime FRCSEd FDSRCS Registrar J.E. Bowerman FRCSEd FDRSCS Consultant P.J. Weller FRCSEd FDSRCPS Senior Registrar 《The British journal of oral & maxillofacial surgery》1990,28(6):367-374
Primary chronic osteomyelitis (chronic diffuse sclerosing osteomyelitis) of the mandible is an uncommon condition, probably arising as a consequence of infection with bacteria of low virulence, in which bone deposition rather than bone resorption occurs. These bacteria are most likely derived from skin or oral mucosa gaining access to bone from the periodontium or through the circulation. Furthermore, delayed hypersensitivity and ischaemic changes within bone may contribute to the inflammatory response, which once initiated is very difficult to eradicate. When the likely aetiological factors are considered a logical approach to management includes the surgical removal of affected bone and the topical application of a broad spectrum antibiotic to the resultant surgical bed. 相似文献
44.
45.
We report a patient with a myelopathy in primary Sjögren's syndrome, proven by salviary gland biopsy and specific antibodies. Under steroid medication, the patient had a remitting and relapsing clinical course. The severity of clinical symptoms correlated with a transient contrast uptake in spinal magnetic resonance imaging. Under a treatment with azathioprine and prednisone the patient has suffered no relapse within the last 20 months. Although this is only a case report, the combination of azathioprine and prednisone may be a valuable medication in chronic cases of Sjögren's syndrome with neurologic symptoms. 相似文献
46.
A distinctive feature of these workshops, in addition to those noted in the introductory overview, is the selection of a relatively isolated location for a 1-week period. This, together with a rich and varied program and an ethos of informality, encourages participants to discuss not only the work presented but also their unpublished work and their intuitions based on preliminary data and analyses. Such an interchange is of inestimable value to the schizophrenia research community. In scientific terms, a panel of concluding discussants (Drs Kendell, Torrey, and Waddington) were in some measure of agreement that genetics, particularly molecular genetics, appears to be experiencing a period of retrenchment, while epidemiology is experiencing something of a renaissance. Maternal influenza was a prominent theme, although the data were far from consistent. It was argued by Dr Wessely that risk for schizophrenia putatively attributable to maternal influenza might be 5% to 10% of all cases, indicating a modest effect. Eclectically, Dr Kendell believed the effect to be "real" but slight and fragile, it being sought against large aggregates that almost inevitably result in differing findings from differing countries or from different data bases within a given country. Gender differences were also among the more prominent themes, not just in an epidemiologic context but also in a variety of other studies. This points anew to disturbances in schizophrenia of factors that regulate, or are intimately associated with, sexual dimorphism in brain development. Abnormalities in cerebral asymmetry continue to pervade a variety of research findings and point further to neurodevelopmental anomalies.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
47.
48.
Vieira-de-Abreu A Assis EF Gomes GS Castro-Faria-Neto HC Weller PF Bandeira-Melo C Bozza PT 《American journal of respiratory cell and molecular biology》2005,33(3):254-261
Eosinophils are an important source of leukotriene (LT)C(4), which can be synthesized within lipid bodies-cytoplasmic organelles where eicosanoid formation may take place. Allergy-driven lipid body formation and function have never been investigated. Here, we studied the in vivo induction and role of lipid bodies within eosinophils recruited to sites of allergic inflammation. Using two murine models of allergic inflammation (asthma and pleurisy), we verified that parallel to the eosinophil influx, allergic challenge also induced lipid body formation within recruited eosinophils. Neutralizing antibodies to eotaxin/CCL11, RANTES/CCL5, or CCR3 partially inhibited lipid body formation within recruited eosinophils in the allergic pleurisy model. Likewise, intrapleural administration of RANTES or eotaxin also induced significant influx of eosinophils loaded with lipid bodies. By immunolabeling, we detected the presence of a key enzyme involved in the leukotriene metabolism-5-lipoxygenase-within eosinophil lipid bodies formed in vivo after allergen challenge. Furthermore, specific immunolocalization of newly formed LTC(4) demonstrated that lipid bodies were the sites of formation of this eicosanoid within infiltrating eosinophils. Therefore, allergic inflammation triggers in vivo formation of new lipid bodies within infiltrating eosinophils, a phenomenon largely mediated by eotaxin/RANTES acting via CCR3 receptors. Such in vivo allergen-driven lipid bodies function as intracellular compartments of LTC(4) synthesis. 相似文献
49.
50.
Dementia is characterized clinically by progressive cognitive decline, often with impairment of memory. The pathology of dementias is either focal as with infarcts in Vascular Dementia or diffuse as typified by Alzheimer's disease. In many cases of Alzheimer's disease there is a mixture of focal infarcts and diffuse changes. Diffuse pathology in dementias comprises mainly intracellular and extracellular protein deposits. Intracellular inclusions are of tau protein (Alzheimer's disease; and some frontotemporal dementias), alpha-synuclein (Dementia with Lewy bodies) and huntingtin (Huntington's disease). Soluble and insoluble peptides also accumulate in the extracellular spaces of brain parenchyma in dementias with diffuse pathology, mainly amyloid-beta (Abeta) in parenchymal plaques and in artery walls as cerebral amyloid angiopathy (Alzheimer's disease and Dementia with Lewy bodies). Insoluble prion protein (PrP) is deposited in brain parenchyma in Creutzfeldt-Jakob disease and other insoluble amyloid peptides accumulate in brain and vessel walls infamilial dementias. The pattern of extracellular deposits in brain and artery walls suggests that there is a failure of elimination of peptides, such as Abeta along perivascular interstitial fluid drainage pathways ("lymphatics") from the aged brain and in Alzheimer's disease. Such failure may be due to reduced pulsations as arteries stiffen with age and cerebrovascular disease. Immunization against Abeta removes insoluble deposits of Abeta from brain parenchyma and may allow improved clearance of soluble Abeta. Reducing cerebrovascular disease and facilitating elimination of Abeta along perivascular drainage routes may offer long-term preventative measuresfor both Vascular Dementia and for Alzheimer's disease. 相似文献