全文获取类型
收费全文 | 8086篇 |
免费 | 622篇 |
国内免费 | 21篇 |
专业分类
耳鼻咽喉 | 62篇 |
儿科学 | 279篇 |
妇产科学 | 263篇 |
基础医学 | 1009篇 |
口腔科学 | 127篇 |
临床医学 | 1138篇 |
内科学 | 1408篇 |
皮肤病学 | 127篇 |
神经病学 | 737篇 |
特种医学 | 190篇 |
外科学 | 812篇 |
综合类 | 61篇 |
一般理论 | 16篇 |
预防医学 | 1104篇 |
眼科学 | 114篇 |
药学 | 602篇 |
中国医学 | 13篇 |
肿瘤学 | 667篇 |
出版年
2024年 | 23篇 |
2023年 | 113篇 |
2022年 | 124篇 |
2021年 | 230篇 |
2020年 | 198篇 |
2019年 | 244篇 |
2018年 | 257篇 |
2017年 | 211篇 |
2016年 | 258篇 |
2015年 | 253篇 |
2014年 | 309篇 |
2013年 | 462篇 |
2012年 | 660篇 |
2011年 | 732篇 |
2010年 | 361篇 |
2009年 | 295篇 |
2008年 | 550篇 |
2007年 | 536篇 |
2006年 | 535篇 |
2005年 | 491篇 |
2004年 | 368篇 |
2003年 | 404篇 |
2002年 | 355篇 |
2001年 | 69篇 |
2000年 | 41篇 |
1999年 | 60篇 |
1998年 | 64篇 |
1997年 | 45篇 |
1996年 | 46篇 |
1995年 | 35篇 |
1994年 | 41篇 |
1993年 | 31篇 |
1992年 | 36篇 |
1991年 | 16篇 |
1990年 | 29篇 |
1989年 | 20篇 |
1988年 | 15篇 |
1987年 | 14篇 |
1986年 | 18篇 |
1984年 | 9篇 |
1983年 | 16篇 |
1982年 | 14篇 |
1981年 | 13篇 |
1980年 | 9篇 |
1979年 | 15篇 |
1978年 | 8篇 |
1977年 | 8篇 |
1975年 | 8篇 |
1974年 | 15篇 |
1973年 | 8篇 |
排序方式: 共有8729条查询结果,搜索用时 15 毫秒
31.
32.
Superior mesenteric vein thrombosis after splenectomy is very rare. In the case described of a patient presenting with acute abdominal pain the diagnosis was made primarily by real-time and Doppler ultrasonography. This reduced the time elapsing before it was recognized that angiography and subsequent thrombectomy were indicated. 相似文献
33.
J. -Y. Jenny G. Jenny J. Gaudias 《European journal of orthopaedic surgery & traumatology : orthopedie traumatologie》1995,5(1):79-82
Summary 730 consecutive acute reamed intramedullary locked nailing of tibial fractures were studied, according to Gustilo’s classification
of soft tissue lesions for the open fractures. There is a significant increase of post-operative infection rate if the tibial
fracture is open, and the relative risk increases with the severity of soft tissue lesions. The comparison of these figures
with those of other methods of treatment and the mechanical and clinical advantages of nailing leads us to propose this method
for treatment of grade I, II and IIIa open fractures, while external the fixator seems better adapted for IIIb and c open
fractures.
European Bone and Joint Infection Society Meeting, München, Germany, October 7–9, 1993 相似文献
34.
Jenny E Westin Linda Vercammen Elissa M Strome Christine Konradi M Angela Cenci 《Neuropsychopharmacology》2007,62(7):800-810
BACKGROUND: We examined the activation pattern of extracellular signal-regulated kinase 1 and 2 (ERK1/2) and its dependence on D1 versus D2 dopamine receptors in hemiparkinsonian rats treated with 3,4-dihydroxyphenyl-L-alanine (L-DOPA). METHODS: 6-Hydroxydopamine-lesioned rats were treated acutely or chronically with L-DOPA in combination with antagonists for D1 or D2 receptors. Development of dyskinesia was monitored in animals receiving chronic drug treatment. Phosphorylation of ERK1/2, mitogen- and stress-activated protein kinase-1 (MSK-1), and the levels of FosB/DeltaFosB expression were examined immunohistochemically. RESULTS: L-DOPA treatment caused phosphorylation of ERK1/2 in the dopamine-denervated striatum after acute and chronic administration. Similar levels were observed in matrix and striosomes, and in enkephalin-positive and dynorphin-positive neurons. The severity of dyskinesia was positively correlated with phospho-ERK1/2 levels. Phosphorylation of ERK1/2 and MSK-1 was dose-dependently blocked by SCH23390, but not by raclopride. SCH23390 also inhibited the development of dyskinesia and the induction of FosB/DeltaFosB. CONCLUSIONS: L-DOPA produces pronounced activation of ERK1/2 signaling in the dopamine-denervated striatum through a D1-receptor-dependent mechanism. This effect is associated with the development of dyskinesia. Phosphorylated ERK1/2 is localized to both dynorphinergic and enkephalinergic striatal neurons, suggesting a general role of ERK1/2 as a plasticity molecule during L-DOPA treatment. 相似文献
35.
Vinay Puri Andrew McQuillin Khalid Choudhury Susmita Datta Jonathan Pimm Srinivasa Thirumalai Robert Krasucki Jacob Lawrence Digby Quested Nicholas Bass Helen Moorey Jenny Morgan Bhaskar Punukollu Gomathinayagam Kandasami David Curtis Hugh Gurling 《Neuropsychopharmacology》2007,61(7):873-879
BACKGROUND: Linkage studies by us and others have confirmed that chromosome 1q23.3 is a susceptibility locus for schizophrenia. Based on this information, several research groups have published evidence that markers within both the RGS4 and CAPON genes, which are 700 kb apart, independently showed allelic association with schizophrenia. Tests of allelic association with both of these genes in our case control sample were negative. Therefore, we carried out further fine mapping between the RGS4 and CAPON genes. METHODS: Twenty-nine SNP and microsatellite markers in the 1q23.3 region were genotyped in the United Kingdom based sample of 450 cases and 450 supernormal control subjects. RESULTS: We detected positive allelic association after the eighth marker was genotyped and found that three microsatellite markers (p = .011, p = .014, p = .049) and two SNPs (p = .004, p = .043) localized in the 700 kb region between the RGS4 and CAPON genes, within the UHMK1 gene, were associated with schizophrenia. Tests of significance for marker rs10494370 remained significant following Bonferroni correction (alpha = .006) for multiple tests. Tests of haplotypic association were also significant for UHMK1 (p = .009) using empirical permutation tests, which make it unnecessary to further correct for both multiple alleles and multiple markers. CONCLUSIONS: These results provide preliminary evidence that the UHMK1 gene increases susceptibility to schizophrenia. Further confirmation in adequately powered samples is needed. UHMK1 is a serine threonine kinase nuclear protein and is highly expressed in regions of the brain implicated in schizophrenia. 相似文献
36.
Margrit Klingner Jenny Apelt Ashok Kumar Dietlind Sorger Osama Sabri J?rg Steinbach Matthias Scheunemann Reinhard Schliebs 《International journal of developmental neuroscience》2003,21(7):357-369
Cholinergic deficits in Alzheimer's disease are accompanied by a number of alterations in other transmitter systems including glutamate, noradrenaline and serotonin, suggesting the involvement also of other neurotransmitter systems in the pathogenesis of the disease. To address the question whether beta-amyloid may contribute to these deficits, brain tissue from transgenic Tg2576 mice with Alzheimer plaque pathology at ages of 5 (still no significant plaque load) and 17 months (moderate to high cortical beta-amyloid plaque load) were examined for a number of cholinergic and non-cholinergic markers. Transgenic mice with no significant plaque load demonstrated reduced hemicholinium-3 (HCh-3) binding to choline uptake sites in anterior brain regions as compared to non-transgenic littermates, while in aged transgenic mice with high number of plaque deposits decreased HCh-3 binding levels were accompanied by increased vesicular acetylcholine transporter binding in selected cortical brain regions. In aged transgenic mice GABA(A), NMDA, AMPA, kainate, and beta-adrenergic as well 5-HT(1A)- and 5-HT(2A)-receptor binding levels were hardly affected, whereas alpha(1)- and alpha(2)-adrenoceptor binding was increased in selected cerebral cortical regions as compared to non-transgenic littermates. The development of changes in both cholinergic and non-cholinergic markers in transgenic Tg2576 mouse brain already before the onset of progressive plaque deposition provides in vivo evidence of a modulatory role of soluble beta-amyloid on cortical neurotransmission and may be referred to the deficits in learning and memory observed in these mice also before significant plaque load. 相似文献
37.
Cross-linking induced interactions between the membrane form of immunoglobulin (mIg) and the cytoskeletal matrix have been described by several groups. To date, the function of mIgM association with the cytoskeleton is not yet understood. Delineation of the molecular basis of these interactions will be instrumental in elucidating their function. We have previously shown that the Igα/β heterodimer is not required for ligand-induced mIgM binding to the cytoskeleton. In this study, we have investigated the role of other B cell-specific proteins in mediating these interactions. For this, we expressed mIgM in the non-hematopoietic human cervical carcinoma cell line HeLa S3 and verified the capacity of the surface-expressed IgM to interact with the cytoskeletal matrix upon cross-linking with anti-μ chain antibodies. We show here that only the mIgM molecule itself and no other B cell-specific protein(s) is required in mediating mIgM interactions with actin filaments. In an attempt to determine the cytoskeleton-binding site of mIgM we investigated the role of the cytoplasmic tail of mIgM (KVK) in binding the receptor to actin-based microfilaments. Using mutated forms of mIgM expressed in J558L cells, we show here that KVK plays a role in mediating these interactions. The absence of KVK did not, however, completely abrogate mIgM-cytoskeletal interactions, suggesting that there are additional molecular requirements for the ligand-induced mIgM binding to the cytoskeletal matrix. 相似文献
38.
Reflective inquiry in nursing practice or 'revealing images' 总被引:1,自引:0,他引:1
Penelope Cash Jenny Brooker Wendy Penney Janet Reinbold Laurence Strangio 《Nursing inquiry》1997,4(4):246-256
Reflective inquiry in nursing practice or 'revealing images' Nurses live and work in complex practice worlds; worlds of shrinking resources and expanding needs. Reflection through journaling offers unique opportunities to gain insight into practice. What might we learn from one's journal? A reflective journal can be a source of interplay between the self as written and the self as other. Likewise, the journal may act to situate ourselves in practice, while at the same time enabling us to illuminate how and in what ways our understandings have become distorted. The extent to which one's journal is educative depends upon the manner in which one chooses to use it as a transformative tool, a tool that might well be described as a process of healing and enlightenment. In order to illustrate the reflexive nature of journaling, this paper is presented as a play reading, where a conversation about practice stories between the different aspects of the nurse's self is depicted. In adopting a play reading, an alternative pedagogical tool is used to illustrate different methodologies exemplifying the emergence of how and in what ways we develop and reconstruct our understanding in nursing. 相似文献
39.
40.
Andersson M Rönnmark J Areström I Nygren PA Ahlborg N 《Journal of immunological methods》2003,283(1-2):225-234
Measurement of human serum molecules with two-site ELISA can be biased by the presence of human heterophilic anti-animal immunoglobulin antibodies (HAIA) that cause false-positive signals by cross-linking the monoclonal (mAb) and/or polyclonal antibodies (pAb) used for the pre- (capture) and post-analyte steps (detection). To evaluate a novel ELISA format designed to avoid interference by HAIA, a target-specific non-immunoglobulin (Ig) affinity protein (affibody) was used to replace one of the antibodies. First, a human IgA-binding affibody (Z(IgA)) selected by phage display technology from a combinatorial library of a single Staphylococcus aureus protein A domain was used. The detection range of IgA standard using an ELISA based on Z(IgA) for capture and goat pAb against IgA (pAb(IgA)) for detection was comparable with that of using pAb(IgA) for both capture and detection. Secondly, another affibody (Z(Apo)) was combined with mAb and used to detect recombinant human apolipoprotein A-1. The affibody/antibody ELISAs were also used to quantify human serum levels of IgA and apolipoprotein A1. To verify that human serum did not cause false-positive signals in the affibody/antibody ELISA format, the ability of human serum to cross-link affibodies, mAb (mouse or rat) and/or pAb (goat) displaying non-matched specificities was assessed; affibodies and antibodies were not cross-linked whereas all combinations of mAb and/or pAb were cross-linked. The combination of affibodies and antibodies for analysis of human serum molecules represents a novel two-site ELISA format which precludes false-positive signals caused by HAIA. 相似文献