全文获取类型
收费全文 | 128882篇 |
免费 | 11257篇 |
国内免费 | 6629篇 |
专业分类
耳鼻咽喉 | 1224篇 |
儿科学 | 1959篇 |
妇产科学 | 2931篇 |
基础医学 | 13464篇 |
口腔科学 | 2678篇 |
临床医学 | 15986篇 |
内科学 | 20151篇 |
皮肤病学 | 1590篇 |
神经病学 | 6397篇 |
特种医学 | 4201篇 |
外国民族医学 | 40篇 |
外科学 | 13342篇 |
综合类 | 19315篇 |
现状与发展 | 20篇 |
一般理论 | 18篇 |
预防医学 | 9437篇 |
眼科学 | 3446篇 |
药学 | 13462篇 |
115篇 | |
中国医学 | 6569篇 |
肿瘤学 | 10423篇 |
出版年
2024年 | 348篇 |
2023年 | 1718篇 |
2022年 | 4021篇 |
2021年 | 5457篇 |
2020年 | 4060篇 |
2019年 | 3708篇 |
2018年 | 3942篇 |
2017年 | 3706篇 |
2016年 | 3311篇 |
2015年 | 5239篇 |
2014年 | 6735篇 |
2013年 | 6947篇 |
2012年 | 10124篇 |
2011年 | 10873篇 |
2010年 | 7484篇 |
2009年 | 6150篇 |
2008年 | 7783篇 |
2007年 | 7725篇 |
2006年 | 7317篇 |
2005年 | 6688篇 |
2004年 | 4839篇 |
2003年 | 4400篇 |
2002年 | 3651篇 |
2001年 | 3090篇 |
2000年 | 2847篇 |
1999年 | 2644篇 |
1998年 | 1311篇 |
1997年 | 1220篇 |
1996年 | 986篇 |
1995年 | 948篇 |
1994年 | 885篇 |
1993年 | 504篇 |
1992年 | 889篇 |
1991年 | 801篇 |
1990年 | 668篇 |
1989年 | 569篇 |
1988年 | 525篇 |
1987年 | 450篇 |
1986年 | 357篇 |
1985年 | 284篇 |
1984年 | 184篇 |
1983年 | 167篇 |
1982年 | 95篇 |
1981年 | 93篇 |
1979年 | 140篇 |
1978年 | 111篇 |
1977年 | 83篇 |
1974年 | 94篇 |
1973年 | 72篇 |
1972年 | 87篇 |
排序方式: 共有10000条查询结果,搜索用时 20 毫秒
21.
22.
Jiuhui Jiang Jiuxiang Lin Changrong Ji 《American journal of orthodontics and dentofacial orthopedics》2005,128(4):520-527
A patient with skeletal Class III malocclusion was treated in 2 phases during the early permanent dentition. In phase 1, maxillary protraction was combined with rapid palatal expansion; in phase 2, fixed appliances were placed. The results were good posttreatment, and, 1 year later, a favorable growth tendency could be observed. This report shows that treatment for a patient with skeletal Class III malocclusion can be started in the early permanent dentition, with very good final results. 相似文献
23.
Although many monoclonal antibodies have been made in human colon cancer, none of them are from the Chinese species. Recently, a colon cancer cell line CC-M2 established from a Chinese patient has been completely characterized and used as immunogen to produce monoclonal antibodies. Monoclonal antibodies were produced by standard hybridoma technique. The fusion rate was 95.8%. An isotype IgG1 of high proliferation named as Sam-2 was used in this study. The titers were measured around 10(4). Further studies on MoAb Sam-2 through indirect immunofluorescent and immunoperoxidase tests revealed its good specificity and sensitivity in colorectal cancer tissue. In CEA study, the result indicated that Sam-2 may react on a non-CEA related antigen. For further clinical application, the antigen was identified as a glycoprotein by chemical resistant test. In preliminary studies using sodium dodecyl sulfate-polyacrylamide gel electrophoresis and immunoblotting techniques, Sam-2 could recognize two closed antigens or a dimer antigen with molecular weight 25.2 and 27 Kd respectively. 相似文献
24.
N. H. Chow Y. L. Guo J. S. Lin J. H. Su T. S. Tzai H. R. Guo I. J. Su 《British journal of cancer》1997,75(11):1708-1710
A high incidence of bladder cancer has been documented in an area of chronic arsenic (As) exposure. This study investigates the characteristics of As-associated (n = 49) and other (n = 64) bladder cancers. A higher histological grading was observed for the As-exposed tumours (P = 0.04), but no other difference in pathobiological features or prognosis was found between the two groups. 相似文献
25.
26.
美沙酮联用丁丙诺啡对海洛因依赖重度药瘾戒毒治疗临床研究 总被引:3,自引:0,他引:3
目的 探索对海洛因依赖重度药瘾较理想的戒毒治疗方法。 方法 采用美沙酮与丁丙诺啡联合用药方案 ,对海洛因依赖重度药瘾 41例行戒毒治疗 ,1 2天为一疗程 ,并与单用美沙酮组 2 0例进行比较。 结果 联合用药组控制症状较彻底 ,鸦片类药物戒断症状量表 (OWS)总分平稳下降 ,症状波动小 ,减药顺利 ,两药替换平稳 ,戒毒成功率 73 2 %。 结论 我们认为美沙酮联用丁丙诺啡是一种值得推荐的戒毒治疗方法。 相似文献
27.
Haiyung Cheng Jules I. Schwartz Charles Lin Raju D. Amin James R. Seibold Kenneth C. Lasseter David L. Ebel Dominick J. Tocco J. Douglas Rogers 《Biopharmaceutics & drug disposition》1994,15(5):409-418
MK-679 (R(?)-3-((3-(2-(7-chloro-2-quinolinyl)ethenyl)phenyl)(3-(dimethylamino)-3-oxopropyl)thio)methyl)thio(propanoic acid) is a potent and specific LTD4-receptor antagonist. The disposition of MK-679 was investigated in a three-way crossover study in 12 healthy males receiving single intravenous doses of 75, 250, and 500 mg of MK-679. A greater than proportional increase in the area under the plasma concentration—time curve of MK-679 was observed with increase in dose. The plasma concentration data for each subject fitted well to the differential equations for a two-compartment model with linear tissue distribution and Michaelis-Menten elimination from the central compartment, indicating that the elimination of MK-679 in humans is saturable. In a previous study, the disposition of MK-679 in humans was also dose-dependent when given together with its S(+)-isomer, L-668,018. Thus, the disposition of MK-679 in humans is dose-dependent regardless of the presence of its stereoisomer. Also, the bioavailability of MK-679 was determined in six healthy males receiving simultaneously an oral dose of 250 mg of MK-679 and intravenous infusion of 1 mg 14C-MK-679. Results of this study indicate that the oral bioavailability of MK-679 is nearly quantitative. 相似文献
28.
Clinically significant contact lens induced corneal warpage is seen in a small proportion of soft and rigid contact lens wearers. Previous studies using the keratometer have found no correlation between the fit of the lens and the induced topographic changes. In this study, using computer-assisted topographic analysis, seven eyes (four patients) with rigid contact lens-induced corneal warpage were noted to have topographic abnormalities that correlated with the decentered resting position of the contact lens on the cornea. The warpage topography for each of these corneas was characterized by a relative flattening of the cornea underlying the resting position of the contact lens. Lenses that rode high, for example, produced flattening superiorly and resulted in a relatively steeper contour inferiorly that simulated the topography of early keratoconus patients who had not worn contact lenses. After discontinuing contact lenses the corneal topography returned to a normal pattern in five eyes. Two eyes retained asymmetry that is not characteristic of normal corneas. Up to 6 months was required for the corneas to return to a stable topography after contact lens wear was discontinued. 相似文献
29.
30.
Elevation of prostaglandins and protein in the aqueous humor is an immediate response to Yag-laser anterior capsulotomy. There was a significant correlation between prostaglandins and thromboxane to the elevation of intraocular pressure. The elevation of protein concentration was proportional to the elevation of prostaglandin F1, but not to thromboxane. The biochemical changes in the aqueous humor were more severe as laser power was increased above 3 mj. While the role of prostaglandins in the elevation of intraocular pressure is uncertain, the present data recommend the selection of laser power below 3 mj to avoid pressure rise instead of inhibition of all prostaglandin synthesis by medication. 相似文献