全文获取类型
收费全文 | 932篇 |
免费 | 54篇 |
国内免费 | 21篇 |
专业分类
耳鼻咽喉 | 4篇 |
儿科学 | 44篇 |
妇产科学 | 3篇 |
基础医学 | 106篇 |
口腔科学 | 12篇 |
临床医学 | 84篇 |
内科学 | 256篇 |
皮肤病学 | 24篇 |
神经病学 | 24篇 |
特种医学 | 123篇 |
外科学 | 59篇 |
综合类 | 112篇 |
预防医学 | 74篇 |
眼科学 | 4篇 |
药学 | 37篇 |
中国医学 | 3篇 |
肿瘤学 | 38篇 |
出版年
2023年 | 6篇 |
2022年 | 8篇 |
2021年 | 9篇 |
2020年 | 5篇 |
2019年 | 6篇 |
2018年 | 5篇 |
2017年 | 11篇 |
2016年 | 12篇 |
2015年 | 25篇 |
2014年 | 39篇 |
2013年 | 32篇 |
2012年 | 43篇 |
2011年 | 29篇 |
2010年 | 44篇 |
2009年 | 43篇 |
2008年 | 50篇 |
2007年 | 41篇 |
2006年 | 29篇 |
2005年 | 23篇 |
2004年 | 18篇 |
2003年 | 19篇 |
2002年 | 24篇 |
2001年 | 29篇 |
2000年 | 19篇 |
1999年 | 21篇 |
1998年 | 47篇 |
1997年 | 41篇 |
1996年 | 35篇 |
1995年 | 24篇 |
1994年 | 30篇 |
1993年 | 23篇 |
1992年 | 9篇 |
1991年 | 15篇 |
1990年 | 12篇 |
1989年 | 17篇 |
1988年 | 18篇 |
1987年 | 28篇 |
1986年 | 10篇 |
1985年 | 14篇 |
1984年 | 6篇 |
1983年 | 9篇 |
1982年 | 16篇 |
1981年 | 5篇 |
1980年 | 7篇 |
1979年 | 7篇 |
1978年 | 11篇 |
1977年 | 5篇 |
1976年 | 12篇 |
1975年 | 5篇 |
1974年 | 3篇 |
排序方式: 共有1007条查询结果,搜索用时 0 毫秒
1.
Akira Sawaki Nobumasa Mizuno Kuniyuki Takahashi Tsuneya Nakamura Masahiro Tajika Hiroki Kawai Toshifumi Isaka Hiroshi Imaoka Yasuyuki Okamoto Masatoshi Aoki Hiroyuki Inoue Ahmed AS Salem Yasushi Yatabe Kenji Yamao 《Digestive endoscopy》2006,18(1):40-44
Background: Gastrointestinal stromal tumors (GIST) are one of the most common mesenchymal tumors of the gastrointestinal tract. GIST are defined by positive immunohistochemical staining for KIT or CD34 and thus are generally diagnosed after surgery. Because small GIST are rarely diagnosed before surgery, the clinical course of these small tumors is not clear. The aim of the present study was to follow changes in size and configuration of small GIST that were pathologically confirmed using endoscopic ultrasonography‐guided fine‐needle aspiration biopsy (EUS‐FNAB). Methods: Between July 1997 and December 2003, 16 tumors in 16 patients (10 men and 6 women) with an immunohistochemical diagnosis of GIST were regularly followed in our hospital. The median patient age when EUS‐FNAB was performed was 62 years (range 26–82 years) and the median follow‐up period was 4.9 years (range 0.5–9.6 years). Results: Fourteen tumors showed no remarkable changes in size and shape during follow up compared with the initial diagnosis. Two tumors enlarged: one tumor approximately doubled its diameter in 8 years and the other tumor increased from 1.8 cm at diagnosis to up to 10 cm after only 2 years. Doubling time of the latter tumor was calculated as 3.1 months. Conclusions: We conclude that EUS‐FNAB might be a good modality for final diagnosis of GIST without surgery, and that GIST without rapid growth on follow up can be endoscopically followed. 相似文献
2.
Coronary artery bypass grafts: visualization with MR imaging 总被引:1,自引:0,他引:1
3.
4.
5.
A case of a rare anomaly of the common bile duct associated with an abnormal arrangement of the pancreaticobiliary ductal union 总被引:1,自引:0,他引:1
L E Loria K Yamamoto T Eto T Tomioka T Miyamoto N Mochinaga R Tsuchiya 《The Japanese journal of surgery》1988,18(6):718-724
A 39 year-old Japanese female patient with a duplication of the distal portion of the common bile duct is presented herein. Moreover, an abnormal arrangement of the pancreaticobiliary ductal union, congenital biliary dilatation and carcinoma of the gallbladder were all demonstrated by cholangiographic and endoscopical studies. The patient underwent radical surgery for advanced adenosquamous carcinoma of the gallbladder, and her postoperative course was satisfactory. A reflux of pancreatic juice into the bile duct was demonstrated, but it was eliminated and considered to be a contributory etiologic factor of the gallbladder carcinoma. 相似文献
6.
Competitive control of the self-renewing T cell repertoire 总被引:1,自引:0,他引:1
We develop a mathematical model for the self-renewing part of the T cell
repertoire. Assuming that self-renewing T cells have to be stimulated by
immunogenic MHC-peptide complexes presented on the surfaces of
antigen-presenting cells, we derive a model of T cell growth in which
competition for MHC-peptide complexes limits T cell clone sizes and
regulates the total number of self-renewing T cells in the animal. We show
that for a sufficient diversity and/or degree of cross-reactivity, the
total T cell number hardly depends upon the diversity of the T cell
repertoire or the diversity of the set of presented peptides. Conversely,
for repertoires of lower diversity and/or cross-reactivity, steady-state
total T cell numbers may be limited by the diversity of the T cells. This
provides a possible explanation for the limited repertoire expansion in
some, but not all, mouse T cell re-constitution experiments. We suggest
that the competitive interactions described by our model underlie the
normal T cells numbers observed in transgenic mice, germ-free mice and
various knockout mice.
相似文献
7.
Androstenediol and dehydroepiandrosterone protect mice against lethal bacterial infections and lipopolysaccharide toxicity 总被引:8,自引:0,他引:8
The protective effects of the hormones androstenediol (androstene-3beta, 17beta,-diol; AED) and dehydroepiandrosterone (5-androsten-3beta-ol-17-one; DHEA) on the pathophysiology of two lethal bacterial infections and endotoxin shock were examined. The infections included a gram-positive organism (Enterococcus faecalis) and a gram-negative organism (Pseudomonas aeruginosa). Both hormones protected mice from the lethal bacterial infections and from lipopolysaccharide (LPS) challenge. Treatment of animals lethally infected with P. aeruginosa with DHEA resulted in a 43% protection whereas treatment with AED gave a 67% protection. Both hormones also protected completely animals infected with an LD50 dose of E. faecalis. Similarly, the 88% mortality rate seen in LPS challenge was reduced to 17% and 8.5%, by treatment with DHEA and AED, respectively. The protective influences of both steroids were shown not to be directly antibacterial, but primarily an indirect antitoxin reaction. DHEA appears to mediate its protective effect by a mechanism that blocks the toxin-induced production of pathophysiological levels of tumour necrosis factor-alpha (TNF-alpha) and interleukin-1. AED usually had greater protective effects than DHEA; however, the AED effect was independent of TNF-alpha suppression, both in vivo and in vitro. The data suggest that both DHEA and AED may have a role in the neuro-endocrine regulation of antibacterial immune resistance. 相似文献
8.
Survey of CAG/CTG repeats in human cDNAs representing new genes: candidates for inherited neurological disorders 总被引:3,自引:2,他引:3
Neri C; Albanese V; Lebre AS; Holbert S; Saada C; Bougueleret L; Meier-Ewert S; Le Gall I; Millasseau P; Bui H; Giudicelli C; Massart C; Guillou S; Gervy P; Poullier E; Rigault P; Weissenbach J; Lennon G; Chumakov I; Dausset J; Lehrach H; Cohen D; Cann HM 《Human molecular genetics》1996,5(7):1001-1009
9.
W L Kos R M Loria M J Snodgrass D Cohen T G Thorpe A M Kaplan 《Infection and immunity》1979,26(2):658-667
Previous experiments showed that nutritionally induced hypercholesteremia in mice caused an increase in susceptibility to coxsackievirus B, with a marked suppression of cellular infiltrates in infected tissues and an increased mortality. The present studies demonstrated that a hypercholesteremic diet was associated with an inhibition in host resistance as measured by susceptibility to Listeria monocytogenes infection and the growth of two transplanted syngeneic murine tumors. Moreover, the ability of Corynebacterium parvum to induce regression of a transplanted methylcholanthrene-induced fibrosarcoma was inhibited in hypercholesteremic hosts, as was the histiocytic infiltration normally accompanying C. parvum inoculation. In contrast, the peritoneal macrophages from C. parvum-treated hypercholesteremic mice were indistinguishable from similarly treated macrophages from normal mice with respect to their in vitro tumoricidal activity and the presence of a cell surface antigen associated with activated macrophages. Hypercholesteremia was also associated with a decreased antibody response to sheep erythrocytes in vivo, but dit not appear to exert a detrimental effect on B- or T-cell blastogenesis when tested in vitro. The findings that the hypercholesteremic diet was associated with an impairment in the host immune response and increased susceptibility to viral, bacterial, and tumor cell challenge are discussed with respect to virus-lipid interactions in the pathogenesis of atherogenesis and diabetes mellitus. 相似文献
10.