全文获取类型
收费全文 | 20490篇 |
免费 | 1330篇 |
国内免费 | 24篇 |
专业分类
耳鼻咽喉 | 208篇 |
儿科学 | 745篇 |
妇产科学 | 735篇 |
基础医学 | 2768篇 |
口腔科学 | 261篇 |
临床医学 | 3151篇 |
内科学 | 3453篇 |
皮肤病学 | 394篇 |
神经病学 | 1833篇 |
特种医学 | 445篇 |
外科学 | 2116篇 |
综合类 | 343篇 |
一般理论 | 18篇 |
预防医学 | 2361篇 |
眼科学 | 401篇 |
药学 | 1316篇 |
中国医学 | 21篇 |
肿瘤学 | 1275篇 |
出版年
2023年 | 119篇 |
2022年 | 207篇 |
2021年 | 458篇 |
2020年 | 336篇 |
2019年 | 444篇 |
2018年 | 471篇 |
2017年 | 357篇 |
2016年 | 425篇 |
2015年 | 465篇 |
2014年 | 636篇 |
2013年 | 925篇 |
2012年 | 1457篇 |
2011年 | 1576篇 |
2010年 | 850篇 |
2009年 | 702篇 |
2008年 | 1344篇 |
2007年 | 1377篇 |
2006年 | 1275篇 |
2005年 | 1280篇 |
2004年 | 1203篇 |
2003年 | 1186篇 |
2002年 | 972篇 |
2001年 | 216篇 |
2000年 | 231篇 |
1999年 | 214篇 |
1998年 | 208篇 |
1997年 | 209篇 |
1996年 | 149篇 |
1995年 | 123篇 |
1994年 | 129篇 |
1993年 | 108篇 |
1992年 | 142篇 |
1991年 | 127篇 |
1990年 | 119篇 |
1989年 | 116篇 |
1988年 | 107篇 |
1987年 | 104篇 |
1986年 | 114篇 |
1985年 | 102篇 |
1984年 | 105篇 |
1983年 | 89篇 |
1982年 | 86篇 |
1981年 | 70篇 |
1980年 | 64篇 |
1979年 | 66篇 |
1978年 | 50篇 |
1977年 | 46篇 |
1976年 | 40篇 |
1974年 | 40篇 |
1972年 | 42篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
101.
Mosaic ring 12p and total anomalous pulmonary venous return 总被引:1,自引:0,他引:1
Harris DL Siu BL Hummel M Harbert K Senft J Sargent L Wenger SL 《American journal of medical genetics. Part A》2004,131(1):91-93
An infant born with total anomalous pulmonary venous return (TAPVR) was found to have an extra chromosome present as a small ring. Spectral karyotyping and FISH analysis identified the material as a duplication involving the short arm of chromosome 12. Previous cases describing a variety of cytogenetic abnormalities that have been associated with TAPVR are reviewed along with prior cases of duplication 12p with their associated findings. We believe ours is the first case to report the occurrence of mosaic ring 12p and its association with TAPVR. 相似文献
102.
C Brautbar O Yehuda S Eisenberg N Cohen A Amar R Sharon K Fried M Aghasi T Cohen 《Tissue antigens》1983,21(3):233-237
A large family with three children affected with the autosomal recessive disease of Cerebrotendinous Xanthomatosis (CTX) was studied for class I (HLA-A,B,C) and class II antigens (HLA-DR,D,SB), properdin factor B and glyoxalase. The extensive typing revealed an informative cross-over between HLA-B and Bf, indicating that Bf is located centromeric to the HLA-B locus and segregated in this family with HLA-D/DR. The parents in this family were first cousins and their parents were also first cousins. Three of their four haplotypes share B14, BfS, DR1, Dx and SB4 and may be identical by descent. The three affected children carried among them all four parental haplotypes, indicating that close linkage of the CTX locus to HLA is unlikely. 相似文献
103.
Impact of a Summer Camp Experience on Daily Activity and Family Interactions Among Children with Cancer 总被引:1,自引:0,他引:1
Smith Karen E.; Gotlieb Sharon; Gurwitch Robin H.; Blotcky Alan D. 《Journal of pediatric psychology》1987,12(4):533-542
Eighteen pediatric cancer patients and their families participatedin a longitudinal study to assess the effects of a camp experienceon daily activity and family interactions. Based on maternalreport, changes were found in the amount of time these childrenspent in social, physical, and self-engaged activities. Mothersand a sibling closest in age to the patient also noted changesin their own frequency of activities spent with the family andwith others. These changes were evident when comparing measuresobtained 2 weeks prior to and 2 weeks after camp. Many changeswere still present 1 month after attending camp. These datasupport the use of a camp experience as an intervention to facilitatea return to more normal, healthy functioning by pediatric cancerpatients and their families. 相似文献
104.
Allicin inhibits SDF-1alpha-induced T cell interactions with fibronectin and endothelial cells by down-regulating cytoskeleton rearrangement, Pyk-2 phosphorylation and VLA-4 expression 总被引:2,自引:0,他引:2 下载免费PDF全文
Sela U Ganor S Hecht I Brill A Miron T Rabinkov A Wilchek M Mirelman D Lider O Hershkoviz R 《Immunology》2004,111(4):391-399
Allicin, a major ingredient of fresh garlic extract that is produced during the crushing of garlic cloves, exerts various beneficial biological effects, including a broad spectrum of antimicrobial activity, antihyperlipidaemic and antihypertensive effects. However, how allicin affects the immune system is less well known, and its effect on human T cells has never been studied. Here, we examined the in-vitro effects of allicin on the functioning of T cells related to their entry to inflamed extravascular sites. We found that allicin (20-100 microm) inhibits the SDF-1alpha (CXCL12)-induced T cell migration through fibronectin (FN), and that this inhibition is mediated by the down-regulation of (i) the reorganization of cortical actin and the subsequent T cell polarization, and (ii) T cell adhesion to FN. Moreover, allicin also inhibited T cell adhesion to endothelial cells and transendothelial migration. The mechanisms underlying these inhibitory effects of allicin are associated with its ability to down-regulate the phosphorylation of Pyk2, an intracellular member of the focal adhesion kinases, and to reduce the expression of the VCAM-1- and FN-specific alpha4beta1-integrin (VLA-4). The ability of allicin to down-regulate these chemokine-induced and VLA-4-mediated T cell functions explains its beneficial biological effects in processes where T cells play an important role and suggests that allicin may be used therapeutically with chronic inflammatory diseases. 相似文献
105.
The rate of HIV-1 disease progression is influenced by several factors that include pathogen and host genetic variations and the quality of antiviral immune responses. The CD8+ cell non-cytotoxic antiviral response (CNAR) substantially suppresses HIV replication in CD4+ cells and is positively associated with an asymptomatic clinical state. Traditionally, the measurement of CNAR has required several culture procedures and costly reagents. Here we report the development and validation of a screening assay for detection of CNAR that accurately identifies individuals benefiting from this response. Use of the CNAR screening assay should facilitate the evaluation of this important immune parameter in studies of HIV pathogenesis, resistance to infection, and vaccine development. 相似文献
106.
Diagnosis of gastrointestinal stromal tumors: A consensus approach 总被引:258,自引:0,他引:258
Fletcher CD Berman JJ Corless C Gorstein F Lasota J Longley BJ Miettinen M O'Leary TJ Remotti H Rubin BP Shmookler B Sobin LH Weiss SW 《Human pathology》2002,33(5):459-465
As a result of major recent advances in understanding the biology of gastrointestinal stromal tumors (GISTs), specifically recognition of the central role of activating KIT mutations and associated KIT protein expression in these lesions, and the development of novel and effective therapy for GISTs using the receptor tyrosine kinase inhibitor STI-571, these tumors have become the focus of considerable attention by pathologists, clinicians, and patients. Stromal/mesenchymal tumors of the gastrointestinal tract have long been a source of confusion and controversy with regard to classification, line(s) of differentiation, and prognostication. Characterization of the KIT pathway and its phenotypic implications has helped to resolve some but not all of these issues. Given the now critical role of accurate and reproducible pathologic diagnosis in ensuring appropriate treatment for patients with GIST, the National Institutes of Health convened a GIST workshop in April 2001 with the goal of developing a consensus approach to diagnosis and morphologic prognostication. Key elements of the consensus, as described herein, are the defining role of KIT immunopositivity in diagnosis and a proposed scheme for estimating metastatic risk in these lesions, based on tumor size and mitotic count, recognizing that it is probably unwise to use the definitive term "benign" for any GIST, at least at the present time. 相似文献
107.
A gene for autosomal recessive limb-girdle muscular dystrophy maps to chromosome 2p 总被引:10,自引:3,他引:10
Bashlr Rumaisa; Strachan Tom; Keers Sharon; Stephenson Anthea; Mahjneh Ibrahim; Marconi Giamplero; Nashef Lina; Bushby Kate M. D. 《Human molecular genetics》1994,3(3):455-457
The limb-girdle muscular dystrophies are a clinically and geneticallyheterogeneous group of disorders. We have ostudied two largeinbred families of different ethnic origin and excluded linkageto LGMD2 on chromosome 15q and SCARMD on chromosome 13. Proceedingto a genomic linkage search, we have now identified linkageto markers D2S134 and D2S136 on chromosome 2p (maximum lod score3.57 at zero recombination). The phenotype in the two familieswas similar, with onset in the pelvic girdle musculature inthe late teens and usually relatively slow progression. Thiswork Identifies a second locus for autosomal recessive limb-girdlemuscular dystrophy. 相似文献
108.
Leao RN Oleskevich S Sun H Bautista M Fyffe RE Walmsley B 《Journal of neurophysiology》2004,91(2):1006-1012
We have investigated the fundamental properties of central auditory glycinergic synapses in early postnatal development in normal and congenitally deaf (dn/dn) mice. Glycinergic miniature inhibitory postsynaptic currents (mIPSCs) were recorded using patch-clamp methods in neurons from a brain slice preparation of the medial nucleus of the trapezoid body (MNTB), at 12-14 days postnatal age. Our results show a number of significant differences between normal and deaf mice. The frequency of mIPSCs is greater (50%) in deaf versus normal mice. Mean mIPSC amplitude is smaller in deaf mice than in normal mice (mean mIPSC amplitude: deaf, 64 pA; normal, 106 pA). Peak-scaled fluctuation analysis of mIPSCs showed that mean single channel conductance is greater in the deaf mice (deaf, 64 pS; normal, 45 pS). The mean decay time course of mIPSCs is slower in MNTB neurons from deaf mice (mean half-width: deaf, 2.9 ms; normal, 2.3 ms). Light- and electron-microscopic immunolabeling results showed that MNTB neurons from deaf mice have more (30%) inhibitory synaptic sites (postsynaptic gephyrin clusters) than MNTB neurons in normal mice. Our results demonstrate substantial differences in glycinergic transmission in normal and congenitally deaf mice, supporting a role for activity during development in regulating both synaptic structure (connectivity) and the fundamental (quantal) properties of mIPSCs at central glycinergic synapses. 相似文献
109.
110.