全文获取类型
收费全文 | 2722篇 |
免费 | 165篇 |
国内免费 | 11篇 |
专业分类
耳鼻咽喉 | 27篇 |
儿科学 | 38篇 |
妇产科学 | 44篇 |
基础医学 | 373篇 |
口腔科学 | 130篇 |
临床医学 | 240篇 |
内科学 | 750篇 |
皮肤病学 | 98篇 |
神经病学 | 126篇 |
特种医学 | 62篇 |
外科学 | 382篇 |
综合类 | 5篇 |
一般理论 | 2篇 |
预防医学 | 138篇 |
眼科学 | 45篇 |
药学 | 228篇 |
中国医学 | 5篇 |
肿瘤学 | 205篇 |
出版年
2023年 | 30篇 |
2022年 | 45篇 |
2021年 | 87篇 |
2020年 | 40篇 |
2019年 | 59篇 |
2018年 | 80篇 |
2017年 | 48篇 |
2016年 | 57篇 |
2015年 | 65篇 |
2014年 | 86篇 |
2013年 | 103篇 |
2012年 | 214篇 |
2011年 | 229篇 |
2010年 | 129篇 |
2009年 | 114篇 |
2008年 | 164篇 |
2007年 | 184篇 |
2006年 | 141篇 |
2005年 | 160篇 |
2004年 | 133篇 |
2003年 | 100篇 |
2002年 | 102篇 |
2001年 | 25篇 |
2000年 | 42篇 |
1999年 | 53篇 |
1998年 | 17篇 |
1997年 | 23篇 |
1996年 | 16篇 |
1995年 | 18篇 |
1994年 | 17篇 |
1993年 | 14篇 |
1992年 | 35篇 |
1991年 | 27篇 |
1990年 | 22篇 |
1989年 | 34篇 |
1988年 | 30篇 |
1987年 | 18篇 |
1986年 | 17篇 |
1985年 | 23篇 |
1984年 | 12篇 |
1983年 | 6篇 |
1980年 | 5篇 |
1979年 | 7篇 |
1974年 | 8篇 |
1972年 | 5篇 |
1971年 | 9篇 |
1970年 | 5篇 |
1968年 | 5篇 |
1967年 | 5篇 |
1965年 | 5篇 |
排序方式: 共有2898条查询结果,搜索用时 15 毫秒
1.
Hiroto Kinoshita Hitomi Nishioka Aya Ikeda Kyoko Ikoma Yoichi Sameshima Hidehisa Ohi Mizuki Tatsuno Junka Kouyama Chiaki Kawamoto Tomohiro Mitsui Yuko Tamura Yu Hashimoto Masashi Nishio Tsuyoshi Ogashiwa Yusuke Saigusa Shin Maeda Hideaki Kimura Reiko Kunisaki Kazuhiko Koike 《Journal of gastroenterology and hepatology》2019,34(11):1929-1939
2.
3.
Hisato Takagi Toshiyuki Tanabashi Norikazu Kawai Takuya Umemoto 《European journal of cardio-thoracic surgery》2007,32(2):400; author reply 400-400; author reply 401
4.
5.
The infeasibility of using ten-ring irradiated grafts for tracheal allotransplantation even with omentopexy 总被引:2,自引:0,他引:2
In our previous study, we demonstrated that high-dose 60Co irradiation was able to prevent rejection of canine tracheal allografts. To determine the maximum possible length of these grafts, in the present study we attempted to transplant five-ring and ten-ring tracheal allografts in two groups of five dogs each. Either five or ten rings were excised from donor tracheas and irradiated with 100,000 cGy of 60Co. The irradiated tracheal grafts were transplanted to replace either five- or ten-ring sections of the mediastinal tracheas removed from the recipient dogs. The grafts were covered with omental pedicles and no immunosuppressants were used. Graft incorporation was achieved in four of the five dogs in the five-ring group, and three of these dogs survived for more than 700 days. However, four of the five animals in the ten-ring group died from tracheostenosis accompanied by ischemia within 3 weeks. These findings demonstrate the impossibility of performing ten-ring tracheal allotransplantation using irradiated grafts, even with omentopexy. 相似文献
6.
S Aihara N Murakami R Ishii K Kariya Y Azuma K Hamada J Umemoto S Maeda 《Nihon yakurigaku zasshi. Folia pharmacologica Japonica》1992,100(4):359-365
Antinociceptive effects of sodium hyaluronate (Na-HA) were studied on the basis of improvement in the graded abnormal gait elicited by arthritis induced by intra-articular administration of monosodium urate crystal (MSU) to rats. One hour before MSU injection, intra-articular administration of a 1.0% solution of Na-HA with different molecular weights, ranging from 4.70 x 10(5) to 2.02 x 10(6) (HA-200), improved the score of abnormal gait in a molecular weight-dependent manner in the experimental arthritis model. Similarly, administrations of HA-200 at concentrations ranging from 0.1 to 1.0% prior to MSU treatment resulted in improvement of the score in abnormal gait in a dose-dependent manner. To elucidate the antinociceptive mechanisms of Na-HA, effects of pretreatment with Na-HA (1.0%) of different molecular weights on prostaglandin E2 (PGE2) and bradykinin (BK) releases in synovial fluid 3 hr after MSU injection were studied. Increases in PGE2 and BK concentration in the synovial fluid were depressed in a molecular weight-dependent manner by Na-HA (1.0%) pretreatment. These results indicate that Na-HA attenuates the nociceptive responses inflicted by the MSU-induced arthritis. Such an antinociceptive effect may be due to the inhibition of PGE2 and BK synthesis in the synovial joint of rats. 相似文献
7.
Takahashi S Hitomi J Satoh Y Takahashi T Asakura H Ushiki T 《Archives of histology and cytology》2002,65(1):71-82
The hepatic portal vein has been known to make a spontaneous peristaltic movement in some mammals, including the mouse and rat. To investigate the fine structure of the portal vein in relation to its physiological characteristics, we observed the mouse portal vein by using various histological techniques including conventional light microscopy, videomicroscopy, transmission and scanning electron microscopy, and real-time confocal laser scanning microscopy. The mouse hepatic portal vein was provided with a spiral fold which was produced by the inner layer, i.e. the endothelium and smooth muscles of the wall protruding into the lumen. Longitudinal smooth muscle cells spanned the interval of the fold, like a spirally arranged palisade around the vessel wall. The longitudinal muscle fibers ended at the spiral fold, being partly connected with a network of irregularly shaped smooth muscle cells. This network, hitherto unknown, was recognized to be restricted to the fold in distribution and characterized by numerous gap junctions connecting the muscle cells. Real-time confocal laser scanning microscopy using a Ca2+ sensitive fluorescent dye revealed that a transient and periodic increase in Ca2+ concentration occurred in the longitudinal smooth muscle cells and was transmitted spirally from the intestinal to the hepatic side. These findings indicate that, during the peristaltic movement, the contraction of smooth muscle cells is transmitted along the longitudinal smooth muscles of the portal vein wall toward the liver, presumably controlled by the network of the irregularly-shaped smooth muscle cells in the fold of the portal vein. Light microscopic observation in some specimens indicated an occurrence of cardiac muscle cells outside the smooth muscle layer. Restricted to the site of the porta hepatis in distribution, their involvement in the peristaltic contraction of the portal vein seemed unlikely. 相似文献
8.
Wakabayashi Y Watanabe H Inoue J Takeda N Sakata J Mishima Y Hitomi J Yamamoto T Utsuyama M Niwa O Aizawa S Kominami R 《Nature immunology》2003,4(6):533-539
The gene Bcl11b, which encodes zinc finger proteins, and its paralog, Bcl11a, are associated with immune-system malignancies. We have generated Bcl11b-deficient mice that show a block at the CD4-CD8- double-negative stage of thymocyte development without any impairment in cells of B- or gammadelta T cell lineages. The Bcl11b-/- thymocytes showed unsuccessful recombination of V(beta) to D(beta) and lacked the pre-T cell receptor (TCR) complex on the cell surface, owing to the absence of Tcrb mRNA expression. In addition, we saw profound apoptosis in the thymus of neonatal Bcl11b-/- mice. These results suggest that Bcl11b is a key regulator of both differentiation and survival during thymocyte development. 相似文献
9.
Takenori Miyao Kiyoshi Yasui Hitomi Sakurai Masahiro Yamagishi & Akira Ishihama 《Genes to cells : devoted to molecular & cellular mechanisms》1996,1(9):843-854
Background: Eukaryotic RNA polymerase II is composed of more than 10 polypeptide chains. The minimum and essential subunits for RNA synthesis have not yet been identified. Toward this ultimate goal, we analysed the topological arrangement of the putative subunits. Here we report a subunit–subunit contact network involving subunit 5 of the fission yeast Schizosaccharomyces pombe RNA polymerase II.
Results: The rpb5+ gene encoding subunit 5 of RNA polymerase II was cloned from the fission yeast Schizosaccharomyces pombe . The polypeptide predicted from DNA sequence of the rpb5 + gene consists of 210 amino acids with a calculated molecular weight of 23 914. The homology of the amino acid sequence is 55% and 43% with Saccharomyces cerevisiae RPB5 and human hRPB25, respectively. Far-Western blot analysis of S. pombe RNA polymerase II using 32 P-labelled recombinant Rpb5 fused to glutathione S-transferase (GST) as a probe, indicated that Rpb5 binds strongly to membrane-immobilized Rpb1, Rpb2 and Rpb3 and weakly to Rpb5 and a 15-kDa subunit (Rpb8 or Rpb11). In agreement with this result, the 32 P-labelled Rpb3 probe showed a strong binding signal against Rpb5 in addition to Rpb1 and Rpb2. The existence of Rpb5–Rpb3 contact was supported by detection of complexes formed between these two proteins synthesized in vitro using protein-immobilized beads.
Conclusion: Rpb3 and Rpb5, the putative subunits of RNA polymerase II, associate each other to form binary complexes. These two subunits also bind to the two large subunits, Rpb1 and Rpb2, independently. 相似文献
Results: The rpb5
Conclusion: Rpb3 and Rpb5, the putative subunits of RNA polymerase II, associate each other to form binary complexes. These two subunits also bind to the two large subunits, Rpb1 and Rpb2, independently. 相似文献
10.
We investigated the relationship between Arc (activity-regulated cytoskeleton-associated protein) and Ca(2+)/calmodulin-dependent protein kinase II (CaM kinase II). Arc and CaM kinase II were concentrated in the postsynaptic density. These proteins were accumulated after electroconvulsive treatment. Arc increased about 2.5-fold within 30 min and was maintained at this level for 8h after the stimulation. CaM kinase II also increased within 30 min and remained at this level for at least 24h. The interaction of Arc with CaM kinase II was demonstrated using GST-Arc fusion protein, and confirmed in neuroblastoma cells by immunoprecipitation. We examined the function of Arc by introducing Arc cDNA into neuroblastoma cells expressing CaM kinase II. The cells expressing both Arc and CaM kinase II had longer neurites than those expressing CaM kinase II alone. Arc itself did not promote neurite outgrowth. The growth of neurites by Arc was completely blocked by treatment with KN62, an inhibitor of CaM kinases. These results indicated that Arc potentiated the action of CaM kinase II for neurite extension. 相似文献