全文获取类型
收费全文 | 5232篇 |
免费 | 544篇 |
国内免费 | 161篇 |
专业分类
耳鼻咽喉 | 29篇 |
儿科学 | 89篇 |
妇产科学 | 17篇 |
基础医学 | 686篇 |
口腔科学 | 32篇 |
临床医学 | 604篇 |
内科学 | 764篇 |
皮肤病学 | 60篇 |
神经病学 | 250篇 |
特种医学 | 159篇 |
外科学 | 569篇 |
综合类 | 774篇 |
现状与发展 | 1篇 |
一般理论 | 1篇 |
预防医学 | 372篇 |
眼科学 | 39篇 |
药学 | 640篇 |
10篇 | |
中国医学 | 713篇 |
肿瘤学 | 128篇 |
出版年
2024年 | 20篇 |
2023年 | 121篇 |
2022年 | 199篇 |
2021年 | 294篇 |
2020年 | 280篇 |
2019年 | 202篇 |
2018年 | 199篇 |
2017年 | 228篇 |
2016年 | 220篇 |
2015年 | 175篇 |
2014年 | 312篇 |
2013年 | 428篇 |
2012年 | 283篇 |
2011年 | 319篇 |
2010年 | 251篇 |
2009年 | 253篇 |
2008年 | 240篇 |
2007年 | 232篇 |
2006年 | 200篇 |
2005年 | 211篇 |
2004年 | 130篇 |
2003年 | 128篇 |
2002年 | 122篇 |
2001年 | 106篇 |
2000年 | 89篇 |
1999年 | 58篇 |
1998年 | 60篇 |
1997年 | 60篇 |
1996年 | 61篇 |
1995年 | 51篇 |
1994年 | 62篇 |
1993年 | 44篇 |
1992年 | 32篇 |
1991年 | 27篇 |
1990年 | 35篇 |
1989年 | 20篇 |
1988年 | 20篇 |
1987年 | 16篇 |
1986年 | 6篇 |
1985年 | 36篇 |
1984年 | 22篇 |
1983年 | 15篇 |
1982年 | 17篇 |
1981年 | 12篇 |
1980年 | 12篇 |
1979年 | 10篇 |
1978年 | 8篇 |
1975年 | 3篇 |
1973年 | 2篇 |
1972年 | 2篇 |
排序方式: 共有5937条查询结果,搜索用时 187 毫秒
31.
在78具成年尸体上详细观察了髂总动脉的分支。髂总动脉外侧支的出现率为30.76%,多起于髂总动脉远侧1/3段(43.33%),始端外径为2.38±0.06(0.90~4.20)mm.起自髂总动脉的髂腰动脉的出现率为10.26%,也多起于髂总动脉远侧1/3段,其始端外径为3.03±0.14(2.50~3.80)mm。记录了此两支动脉的走行和分布,并讨论了它们的临床意义。 相似文献
32.
L. B. Dudnik A. N. Tsupko M. A. Shupik G. G. Akhaladze E. I. Galperin L. V. Platonova E. A. Pantaz A. V. Alessenko 《Bulletin of experimental biology and medicine》2008,145(1):33-36
Restoration of bile flow after 9-day cholestasis in rat liver normalized the content of lipid peroxidation products. The removal
of the cholestatic factor after 12-day cholestasis was not followed by recovery of these parameters. We showed that measurement
of serum concentration of lipid peroxidation products in patients with cholelithiasis during the preoperative period holds
promise for selection of the optimum time for surgical treatment and prediction of the risk of postoperative complications.
__________
Translated from Byulleten’ Eksperimental’noi Biologii i Meditsiny, Vol. 145, No. 1, pp. 39–42, January, 2008 相似文献
33.
W Rudnicka N English J Farrant M E North A E Bryant A J Edwards A Stackpoole A D Webster B M Balfour 《Clinical and experimental immunology》1992,87(1):46-52
The triggering of the TCR/CD3 complex by anti-CD3 (OKT3) antibody leads to the formation of T cell clusters. In cultures of T lymphocytes from most normal individuals, the peak of cluster formation occurs at 24 h, but with cells from patients with common variable immunodeficiency (CVI) it was seen earlier at 4-9 h; in addition, the clusters were larger than normal, particularly at 9 h. Cluster formation by CVI and normal cells was dependent on temperature and divalent cations, but did not require Fc receptors. Since OKT3 clustering is known to be dependent on the LFA-1/ICAM-1 adhesion system, the effect of monoclonal antibodies directed against these molecules was tested. A potent inhibitor was the antibody against the common beta chain of the integrin family (CD18), but of four MoAbs against the alpha chains (CD11), three inhibited and one stimulated T cell aggregate formation. Increased expression of LFA-1 or ICAM-1 on CVI patients' T cells could not be demonstrated. The accelerated clustering was therefore probably due to an increase in the proportion of cells carrying the activated form of LFA-1. The formation of large numbers of homotypic lymphocyte clusters might reduce the effective interaction between B and T cells, thus contributing to the depression of immunoglobulin synthesis observed in this disease. 相似文献
34.
A simple numerical simulation of AIDS patient detoxification by a hypothetical extracorporeal device for the removal of viruses, infected white cells, and syncytia has been designed. The mathematical model accounts for healthy blood white cells attacking and destroying the viruses, while at the same time the viruses attack and infect certain white cells. The infected white cells serve as a site for viral growth; eventually the cells lyse, releasing a large number of viruses into the blood stream. The healthy white cells and infected white cells combine to form syncytia, where the virus multiplies, and finally the syncytium ruptures releasing all the virus. This model can be used to predict concentrations over a specified period for the patient. This is a mathematical model to be used as a research and design tool only. 相似文献
35.
Suzuki K Nakajima H Saito Y Saito T Leonard WJ Iwamoto I 《International immunology》2000,12(2):123-132
The common cytokine receptor gamma chain (gamma(c)) is an essential receptor component for IL-2, IL-4, IL-7, IL-9 and IL-15, and thereby gamma(c)-deficient mice exhibit impaired T cell and B cell development. The Janus family tyrosine kinase 3 (Jak3) is known to be associated with gamma(c), and the reported phenotypes of gamma(c)-deficient (gamma(c)(-)) and Jak3-deficient (Jak3(-)) mice are similar, indicating that Jak3 is an essential transducer of gamma(c)-dependent signals. Nevertheless, certain differences have been suggested related to the range of actions of gamma(c) and Jak3. To clarify whether gamma(c)-dependent cytokines can partially transduce their signals without Jak3, we compared lymphocyte development in gamma(c)(-), Jak3(-), and gamma(c) and Jak3 double-deficient (gamma(c)(-)Jak3(-)) mice in the same genetic background. With the exception that T and B cells in Jak3(-) mice express high levels of gamma(c), the defects in thymocyte and peripheral T cell and B cell development are indistinguishable among gamma(c)(-), Jak3(-) and gamma(c)(-)Jak3(-) mice. Interestingly, although Bcl-2 induction was previously suggested to be Jak3-independent, IL-7 cannot induce Bcl-2 expression in CD4 single-positive (SP) thymocytes in either gamma(c)(-) or Jak3(-) mice nor can IL-7 rescue CD4 SP thymocytes from dexamethasone-induced cell death in gamma(c)(-) or Jak3(-) mice. These results indicate that Jak3 is absolutely essential for gamma(c)-dependent T cell and B cell development, and for gamma(c)-dependent prevention of thymocyte apoptosis. 相似文献
36.
37.
A monoclonal IgM antibody (HB-2), produced against a membrane antigen on the Raji, B cell line, reacted by indirect immunofluorescence with 2 to 40% of lymphoblasts from the B cell lines, Raji, Daudi, SN-1036, and SB but not with other types of cell lines, including pre-B, myeloid, melanoma, or T cells. HB-2 antibody reacted with 10 ± 3% of normal blood mononuclear cells, and was unreactive with monocytes, granulocytes, platelets, or erythrocytes. Two-color immunofluorescence revealed that HB-2 antigen expression was confined to cells bearing surface Ig. An interesting finding was the fact that 25% of plasmablasts induced by pokeweed mitogen also expressed the HB-2 antigen. However, pre-B and plasma cells from normal bone marrow did not express the HB-2 antigen either on their membrane surface or in their cytoplasm. Analysis of 85 leukemias revealed that the HB-2 antigen was expressed on acute and chronic B cell leukemias and Burkitt's lymphomas, but not on malignacies of pre-B, T, myelocytic, or plasma cells. The results suggest that expression of the HB-2 antigen is confined to mature B cells. 相似文献
38.
Spleen cells from a Lewis rat immunized with affinity-purified B10 anti-(T,G)-A-L antibody were fused with the non-secreting murine hybridoma SP2/0. Cell lines secreting monoclonal antibodies specific for mu- and kappa-chains, as well as an idiotope on anti-(T,G)-A-L antibodies, were isolated and characterized. The anti-mu and -kappa antibodies, are true anti-isotypes, reacting with sera from all strains of mice tested. The anti-idiotope antibodies recognize a determinant on antibodies binding a GT-containing epitope. The proportion of anti-GAT antibody bearing the idiotope varies markedly in different murine strains. A 1000-fold higher level of antibody from Igha mice than from Ighb and Ighe mice is required to give an equivalent inhibition of the idiotope-anti-idiotope reaction. Analysis of monoclonal antibodies expressing the idiotope indicates that the affinity of binding between idiotope and anti-idiotope can vary by as much as two orders of magnitude. Immunoadsorbants prepared with anti-idiotope antibody bind suppressor factor secreted by a GAT-specific T-cell hybridoma. 相似文献
39.
40.
J A Rump D Jakschiess U Walker M Schlesier P von Wussow H H Peter 《Clinical and experimental immunology》1995,101(1):89-93
The underlying immunopathogenic mechanism of CVID has been suspected to involve a chronic viral infection or an autoimmune condition. However, formal proof of viral infection is lacking. Measurement of MxA-protein in leucocyte lysates is a sensitive test for evaluating the activation of the host's interferon system. Both viral infections and autoimmune diseases such as systemic lupus erythematosus (SLE) strongly induce MxA-protein in peripheral leucocytes. We therefore examined 15 patients with longlasting hypogammaglobulinaemia for MxA-protein induction in vivo: 13 patients suffered from CVID, one from hyper-IgM syndrome, and one patient had chronic B lymphocytic leukaemia associated with immunoglobulin deficiency and chronic papilloma virus infection (condylomata accuminata). Only the latter patient exhibited a strong MxA-protein expression; two CVID patients were borderline positive, and the remaining 12 patients including the hyper-IgM syndrome were MxA-protein-negative. There was no relationship between MxA expression and low CD4/CD8 ratios or increased CD8/CD57+ T cell counts, although both conditions are often observed in CVID as well as in chronic viral infections. When exposed in vitro to interferon-alpha (IFN-alpha), peripheral blood leucocytes of four MxA-negative patients were capable of producing normal amounts of MxA-protein. Taken together, these results argue against a viral or autoimmune pathogenesis of CVID. 相似文献