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81.
Thanavala Y Mahoney M Pal S Scott A Richter L Natarajan N Goodwin P Arntzen CJ Mason HS 《Proceedings of the National Academy of Sciences of the United States of America》2005,102(9):3378-3382
A double-blind placebo-controlled clinical trial evaluated the immunogenicity of hepatitis B surface antigen (HBsAg) expressed in potatoes and delivered orally to previously vaccinated individuals. The potatoes accumulated HBsAg at approximately 8.5 microg/g of potato tuber, and doses of 100 g of tuber were administered by ingestion. The correlate of protection for hepatitis B virus, a nonenteric pathogen, is blood serum antibody titers against HBsAg. After volunteers ate uncooked potatoes, serum anti-HBsAg titers increased in 10 of 16 volunteers (62.5%) who ate three doses of potatoes; in 9 of 17 volunteers (52.9%) who ate two doses of transgenic potatoes; and in none of the volunteers who ate nontransgenic potatoes. These results were achieved without the coadministration of a mucosal adjuvant or the need for buffering stomach pH. We conclude that a plant-derived orally delivered vaccine for prevention of hepatitis B virus should be considered as a viable component of a global immunization program. 相似文献
82.
This article reports the cytodiagnosis of three cases of retinoblastoma in children aged 1.5, 2.5, and 5 yr. Two of them were diagnosed by fine-needle aspiration cytology of the primary tumor and one by aqueous cytology. The tumor cells were usually round to oval, small and uniform, with scanty cytoplasm; they generally occurred in closely packed clusters of variable sizes. We discuss the differential diagnosis of retinoblastoma with other round-cell tumors of childhood involving the orbit. 相似文献
83.
Jon-David R. Schwalm Harindra C. Wijeysundera Jack V. Tu Helen Guo Kori J. Kingsbury Madhu K. Natarajan 《The Canadian journal of cardiology》2014
Background
The Variation in Revascularization Practice in Ontario (VRPO) project helped describe variations in revascularization across Ontario. Coronary anatomy was the most important predictor of revascularization strategy. We conducted a novel angiographic substudy of the VRPO cohort to: (1) validate “real-world” coronary angiographic reporting in the province of Ontario; and (2) understand the relationship between variability in revascularization and coronary anatomy complexity.Methods
Seventeen hundred eighty-seven angiograms from 17 cardiac centres were randomly sampled from the VRPO cohort. The core lab assessment involved blinded interpretation of each angiographic film. A comparison of agreement in coronary anatomy and treatment strategy between abstracted chart data from the VRPO study and blinded film review was undertaken. Synergy Between Percutaneous Coronary Intervention With Taxus and Cardiac Surgery (SYNTAX) scores were calculated for all patients with multivessel disease.Results
The weighted κ statistic for coronary anatomy was 0.75 (95% confidence interval, 0.72-0.77), suggesting substantial agreement between abstracted chart data and blinded film review. The weighted κ for revascularization strategy was 0.51 (95% confidence interval, 0.47-0.54) suggesting only moderate agreement. There were no significant differences in the mean/median SYNTAX scores across all 4 percutaneous coronary intervention: coronary artery bypass graft (CABG) groups.Conclusions
Abstracted chart data in the VRPO project provides a valid assessment of coronary anatomy and furthermore serves as validation of “real-world” coronary angiographic reporting in the province of Ontario. The uniform distribution of coronary complexity across centres in Ontario, with respect to the SYNTAX score, suggests the variation of percutaneous coronary intervention: CABG ratio is not related to a difference in coronary anatomy complexity across sites, but rather a difference in management strategies for the same anatomy. 相似文献84.
C. Johnson R. Baggaley S. Forsythe H. van Rooyen N. Ford S. Napierala Mavedzenge E. Corbett P. Natarajan M. Taegtmeyer 《AIDS and behavior》2014,18(4):391-395
HIV self-testing (HIVST), a process in which an individual performs a HIV rapid diagnostic test and interprets the result in private, is an emerging approach that is well accepted, potentially cost-effective and empowering for those who may not otherwise test. To further explore the potential of HIVST, the Liverpool School of Tropical Medicine and World Health Organization held the first global symposium on the legal, ethical, gender, human rights and public health implications of HIVST. The meeting highlighted the potential of HIVST to increase access to and uptake of HIV testing, and emphasized the need to further develop evidence around the quality of HIVST and linkage to post-test services, and to assess the risks and the benefits associated with scale-up. This special issue of AIDS and Behavior links directly to the symposium and presents some of the latest research and thinking on the scale-up of HIV self-testing. 相似文献
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89.
Modulation of in vitro eosinophil progenitors by hydrocortisone: role of accessory cells and interleukins 总被引:1,自引:0,他引:1
The growth of human eosinophil progenitors (CFU-Eo) and the modulation of growth by hydrocortisone were studied as functions of the presence of lymphocytes and monocytes in marrow cells under study; and the source of colony-stimulating factors, specifically, media conditioned by macrophage-like cell line, GCT; phytohemagglutinin-stimulated mononuclear cells (PHA-LCM); or the T cell line, MO. CFU-Eo growth was greatest in marrow containing accessory cells as compared to marrow depleted of accessory cells; and in marrow treated with phytohemagglutinin-stimulated leukocyte conditioned media (PHA-LCM) or MO (T cell line)-conditioned medium (MO-CM) as compared with GCT cell- conditioned medium (GCT-CM). Hydrocortisone reproducibly inhibited eosinophil progenitor growth in unfractionated marrow stimulated by GCT- CM. This effect was abrogated by admixing irradiated mononuclear cells or T lymphocytes with the target marrow or by adding interleukin 1 or interleukin 2 (IL-1, IL-2). Inhibition by hydrocortisone did not occur when monocyte and T lymphocyte depleted marrow was studied. Unlike GCT- CM, MO-CM and PHA-LCM stimulated equal proportions of eosinophil progenitors in nondepleted and accessory cell-depleted marrow and demonstrated less hydrocortisone inhibition. However, both GCT-CM and PHA-LCM produced in the presence of hydrocortisone stimulated significantly fewer CFU-Eos in both unfractionated and accessory cell- depleted marrow target populations. These results indicate that the growth of CFU-Eo and inhibition of growth by hydrocortisone is a direct function of a monocyte-T cell interaction and probably is mediated through effects on the production/release of eosinophil colony stimulating factor (Eo-CSF). 相似文献
90.
超声和微泡造影剂介导细胞基因转染的实验研究 总被引:4,自引:2,他引:4
目的 探讨低频超声对细胞基因转染的作用。方法 超声治疗仪频率1MHz,脉冲重复频率100Hz,占空系数20%。质粒DNA为含编码绿荧光蛋白的pEGFP。应用荧光显微镜和流式细胞仪评价细胞基因转染率,台盼蓝染色计算细胞成活率。选用C2C12、3T3-MDEI和CHO3种细胞系为研究对象,加入DNA后辐照不同声强、时间或加入超声造影剂,观察各条件下的细胞基因转染率和成活率。结果 ①超声介导的基因转染与声强和辐射时间有关,最佳剂量为1w/cm^2 20s;②同样超声剂量,较高的声强较早达到最大基因转染率;③较低剂量时,微泡造影剂可使超声介导的基因转染提高2~3倍并可显著提高最高基因转染率。结论 低频超声可介导细胞基因转染,基因转染率不但与超声辐射剂量有关,而且同样剂量时,高声强较早达到最大基因转染率,最佳剂量是1w/cm^2 20s。同时,微泡造影剂可提高超声介导基因转染的最高转染率。 相似文献