全文获取类型
收费全文 | 20182篇 |
免费 | 1235篇 |
国内免费 | 109篇 |
专业分类
耳鼻咽喉 | 271篇 |
儿科学 | 430篇 |
妇产科学 | 419篇 |
基础医学 | 2508篇 |
口腔科学 | 614篇 |
临床医学 | 1665篇 |
内科学 | 5165篇 |
皮肤病学 | 442篇 |
神经病学 | 1717篇 |
特种医学 | 469篇 |
外科学 | 3362篇 |
综合类 | 132篇 |
一般理论 | 8篇 |
预防医学 | 1205篇 |
眼科学 | 610篇 |
药学 | 1065篇 |
1篇 | |
中国医学 | 42篇 |
肿瘤学 | 1401篇 |
出版年
2023年 | 147篇 |
2022年 | 295篇 |
2021年 | 693篇 |
2020年 | 365篇 |
2019年 | 602篇 |
2018年 | 747篇 |
2017年 | 428篇 |
2016年 | 486篇 |
2015年 | 610篇 |
2014年 | 825篇 |
2013年 | 1011篇 |
2012年 | 1713篇 |
2011年 | 1764篇 |
2010年 | 922篇 |
2009年 | 852篇 |
2008年 | 1373篇 |
2007年 | 1435篇 |
2006年 | 1301篇 |
2005年 | 1174篇 |
2004年 | 1019篇 |
2003年 | 857篇 |
2002年 | 799篇 |
2001年 | 109篇 |
2000年 | 94篇 |
1999年 | 141篇 |
1998年 | 179篇 |
1997年 | 134篇 |
1996年 | 120篇 |
1995年 | 129篇 |
1994年 | 114篇 |
1993年 | 114篇 |
1992年 | 88篇 |
1991年 | 62篇 |
1990年 | 50篇 |
1989年 | 53篇 |
1988年 | 46篇 |
1987年 | 42篇 |
1986年 | 49篇 |
1985年 | 35篇 |
1984年 | 55篇 |
1983年 | 46篇 |
1982年 | 58篇 |
1981年 | 58篇 |
1980年 | 38篇 |
1979年 | 32篇 |
1978年 | 29篇 |
1977年 | 30篇 |
1976年 | 24篇 |
1974年 | 21篇 |
1973年 | 22篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
31.
The clinicopathological and immunohistochemical properties of 6 examples of arteriovenous hemangioma, including 2 intraoral lesions, were reviewed. This distinct benign, acquired vascular lesion, infrequently encountered in the literature, is characterized by multiple thick- and thin-walled vascular spaces resembling arteries and veins, respectively. In our study, we performed elastic stains that revealed a prominent venular component, whereas the arterial aspect was inconspicuous to absent. Our aim was also lo elucidate the possible histogenesis of this lesion. Previous reports suggest as pathogenetic mechanisms hamartomatous proliferation either of the subpapillaiy vascular plexus or of the Suquet-Hoyer canal of the true glomus. Our immunohistochemical studies failed to identify typical glooms cells. In addition, we investigated the mast cell count in all lesions and it was found increased. These findings, as well as recent evidence directly implicating mast cells in angiogenesis, can support the theory of hamartomatous proliferation of the subpapillary plexus. One should also not exclude the possibility of a reactive process resulting in the characteristic features of arteriovenous hemangioma. 相似文献
32.
33.
Fixation of cementless acetabular cups: A radiographic 4-8-year study of 102 porous-coated components 总被引:2,自引:0,他引:2
We studied fixation changes over time in 113 porous-coated Howmedica (PCA) cementless acetabular cups inserted in 90 patients 1984-1988. The mean follow-up was 5 years. Radiographic fixation was classified as stable, fibrous-stable, or unstable. 9 cups, 3 in neutral position and 6 vertical, were revised. At follow-up, 40/75 neutral cups were stable versus 7/27 vertical cups. Most stable cups and two thirds of the unstable cups were clinically good. After the first 2 years, 28/75 neutral cups and 10/27 vertical cups changed their fixation: 12 had improved fixation and 26 had a worse one. 相似文献
34.
Cristina Antúnez María Jose Torres Cristobalina Mayorga José L. Corzo Antonio Jurado Luis F. Santamaría-Babi Angel Vera Miguel Blanca 《Pediatric allergy and immunology》2006,17(3):166-174
T cells are known to develop a critical role in the pathogenesis of atopic dermatitis (AD) and bronchial asthma. T cells involved in AD express the skin homing receptor CLA, but no lung homing receptor has been identified in bronchial asthma. We compared different cell markers and the cytokine production in T cells from children with AD or bronchial asthma. We studied the involvement of CLA+ and CLA- T-cell subpopulations in these diseases. We studied 20 children with acute AD lesions, 15 with mild persistent asthma, and 15 non-atopic controls. All patients were sensitized to house dust mite (DP) and evaluated during the acute phase. Total and specific IgE were measured by immunoassay and the expression of different cell markers and the cytokine production was analyzed by flow cytometry in peripheral blood mononuclear cells. Total IgE was significantly higher in AD children and IgE to DP in the asthmatic children. There was a significant increase in CD25+ CD4+ cells in asthmatic children and in HLA-DR+ CD4+ and HLA-DR+ CD8+ cells in AD. In the CD4+ subsets, there was an increase in IL-13, IL-5 and TNF-alpha in AD compared to controls, a decrease in IFN-gamma in asthmatic children compared to controls, and an increase in IL-13, IL5, IL2, TNF-alpha, and IFN-gamma in the AD compared to asthmatic children. Changes in cytokine production were mainly detected in CLA+ cells in AD and in CLA- cells in asthma. Differences exist in total and specific IgE, activation markers, and cytokine patterns between AD children and children with asthma, with the former expressing a Th2 pattern whereas in asthmatic children we only detected a decrease in IFN-gamma. Moreover, the subpopulations (CLA+ vs. CLA-) expressing these changes were different, indicating that the underlying mechanisms in the two diseases are not exactly the same. 相似文献
35.
36.
37.
38.
Jose A. Acosta MD Joseph A. Greenlee MD K. Dean Gubler DO Cary J. Goepfert MD Jerry J. Ragland MD 《American journal of surgery》1995,170(6)
: The use of needle-localization breast biopsy (NLBB) for the early diagnosis of breast cancer is common. The therapeutic adequacy of tumor-free margins following NLBB is unknown. We hypothesized that the presence of residual tumor after reexcision (mastectomy, tylectomy, or quadrantectomy) does not depend on the margin status following NLBB.
: Retrospective cohort analysis was performed on 890 consecutive NLBBs executed between January 1990 and June 1994. Patients with invasive breast neoplasia were divided into two groups based on the tumor margins after NLBB. Group 1 were the women with positive margins, and group 2 had negative margins. Breast specimens after reexcision were reviewed for evidence of residual invasive carcinoma.
: Invasive neoplasia was present in 107 patients (12%). Surgical margins and definitive records of care were avaliable for 96 of them (90%). All 45 patients in group 1 and 38 (75%) of 51 patients in group 2 underwent reexcision of the initial biopsy site (P = 0.36). Residual invasive carcinoma was present in 10 patients (22%) in group 1 and 3 (8%) in group 2 (P = 0.13).
: Invasive breast neoplasia diagnosed by NLBB requires reexcision regardless of tumor margins to achieve complete local surgical eradication of tumor. 相似文献
39.
40.
Jordi Sabadell Jose Luis Sanchez-Iglesias Raquel Ferrer Teresa Higueras Jaume Alijotas Luis Cabero 《The journal of maternal-fetal & neonatal medicine》2007,20(5):423-425
Maternal group B streptococcal infection is an uncommon entity. Herein we describe a case of a 27-year-old-woman who presented life-threateniing group B streptococcus meningitis with an ectopic cervical pregnancy. No other infectious focus have been found. To our knowledge this is the first time that this association has been reported. 相似文献