全文获取类型
收费全文 | 399篇 |
免费 | 30篇 |
国内免费 | 10篇 |
专业分类
耳鼻咽喉 | 1篇 |
儿科学 | 33篇 |
基础医学 | 33篇 |
口腔科学 | 6篇 |
临床医学 | 41篇 |
内科学 | 58篇 |
皮肤病学 | 4篇 |
神经病学 | 4篇 |
特种医学 | 135篇 |
外科学 | 21篇 |
综合类 | 6篇 |
预防医学 | 10篇 |
药学 | 26篇 |
1篇 | |
肿瘤学 | 60篇 |
出版年
2021年 | 8篇 |
2020年 | 7篇 |
2019年 | 5篇 |
2018年 | 4篇 |
2017年 | 5篇 |
2016年 | 4篇 |
2015年 | 4篇 |
2014年 | 2篇 |
2013年 | 6篇 |
2012年 | 16篇 |
2011年 | 5篇 |
2010年 | 4篇 |
2009年 | 10篇 |
2008年 | 12篇 |
2007年 | 13篇 |
2006年 | 15篇 |
2005年 | 5篇 |
2004年 | 5篇 |
2003年 | 9篇 |
2002年 | 3篇 |
2001年 | 4篇 |
2000年 | 3篇 |
1999年 | 9篇 |
1998年 | 18篇 |
1997年 | 16篇 |
1996年 | 26篇 |
1995年 | 15篇 |
1994年 | 21篇 |
1993年 | 16篇 |
1992年 | 4篇 |
1991年 | 6篇 |
1990年 | 6篇 |
1989年 | 18篇 |
1988年 | 15篇 |
1987年 | 19篇 |
1986年 | 11篇 |
1985年 | 10篇 |
1984年 | 8篇 |
1983年 | 12篇 |
1982年 | 10篇 |
1981年 | 9篇 |
1980年 | 8篇 |
1979年 | 5篇 |
1977年 | 6篇 |
1976年 | 9篇 |
1975年 | 2篇 |
1973年 | 2篇 |
1968年 | 1篇 |
1966年 | 2篇 |
1965年 | 1篇 |
排序方式: 共有439条查询结果,搜索用时 31 毫秒
431.
432.
Intrahepatic biliary obstruction was treated in 60 patients (49 with cholangiocarcinoma and 11 with sclerosing cholangitis) who were classified according to the upper limit of their obstruction (Group I, proximal common hepatic duct; Group 2, right and left main hepatic ducts; Group 3, intrahepatic bile ducts). Thirty-six patients underwent percutaneous transhepatic biliary drainage, and 14 underwent catheterization through a T-tube track, Five of this latter group had the T-tube placed to establish a route of access for later interventional radiologic manipulations. Since most diseases that produce intrahepatic biliary obstruction are progressive, the use of any single approach is limited. The advantages of a surgically created route of access combined with the flexibility of interventional radiologic techniques help to maximize the therapy and extend the palliation that many of these patients receive. 相似文献
433.
434.
现代科技的发展促进了能明显改善听障及耳鸣患者生活质量及交流能力的装置的产生与发展。文章回顾了听力损失及相关的听觉功能障碍的生物工程学解决方案,并对各项技术的未来发展方向作出展望。 相似文献
435.
26万女性队列人群中乳腺癌与人工流产关系的研究(上海) 总被引:2,自引:0,他引:2
目的:评估人工流产(指手术流产)对乳腺癌危险性的可能影响.方法:研究在上海267 040例妇女的一项乳房自我检查随机试验的队列人群中进行,由队列研究和巢式病例对照研究两部分组成.结果:依据基线调查表采集的资料分析,人工流产不增加乳腺癌危险性.调整潜在的混淆因素后,OR=1.06(95%CI:0.91~1.25).人工流产次数增加无危险性趋势增加.从更详细的652例乳腺癌病例和694例对照资料分析,得出相似的结果.人工流产发生在首次生育后不增加危险性;少数妇女在首次生育前人工流产以及妊娠13周后人工流产,虽然被观察到危险性有增加,但无显著性统计学意义.结论:在中国,人工流产不是乳腺癌发生的重要原因. 相似文献
436.
White cell-poor blood components are useful in patients with white cell antibodies. White cells are efficiently removed by two different filters, Imugard and Erypur, which have used saline as the filter solution. This study evaluated these filters as to their production of white cell-poor platelets. Pools of random-donor platelet concentrates were filtered. Prefiltration and postfiltration samples were evaluated for percentages of platelet recovery, white cell (WBC) removal, and platelet function. The two filter solutions tested were normal-strength saline (NSS) and fresh-frozen plasma (FFP). Postfiltration samples using NSS showed no measurable platelet aggregation with ADP, epinephrine, or collagen. However, with FFP, both filters showed 100 percent platelet aggregation with ADP, epinephrine, and collagen. The FFP filter solution provided excellent white cell removal in both filters (Imugard: 100% WBC removal or less than 1.0 X 10(6) residual WBC; Erypur: 99.5% removal or greater than 1.0 X 10(7) residual WBC); however, platelet recovery was better with Imugard (95%) than with Erypur (55%). The filtration procedure is an excellent method for the preparation of white cell-poor platelets; however, the quantity of the saline solution recommended for the filtering of red cells must be minimized for platelets. 相似文献
437.
Basic fibroblast growth factor expression in human bone marrow and peripheral blood cells 总被引:9,自引:2,他引:9
We have shown previously that basic fibroblast growth factor (bFGF) is a mitogen for human bone marrow (BM) stromal cells and that bFGF stimulates myelopoiesis in primary BM cultures. In this article, we demonstrate the presence of bFGF in two cell lineages in human BM and peripheral blood as well as the deposition of bFGF into the extracellular matrix of BM stromal cell cultures. In immunofluorescence experiments on BM and peripheral blood smears, megakaryocytes and platelets stained strongly for bFGF, whereas weaker staining was observed in immature and mature cells of the granulocyte series. The presence of bFGF in platelets was confirmed by enzyme-linked immunosorbent assay as well as by immunoprecipitation followed by immunoblotting. bFGF was synthesized by BM stromal cell cultures and was found either cell associated or localized in the nucleus and the nucleoli, and its location was dependent on the fixation procedure used. Addition of exogenous bFGF to stromal cells showed the presence of extracellular binding molecules for this cytokine. bFGF could be released from these sites by soluble heparin or phosphatidylinositol- specific phospholipase C. This study supports the role of bFGF as a stromal cell mitogen and stimulator of myelopoiesis. The data indicate that the stromal cells produce bFGF and that their extracellular matrix can serve as a reservoir for this growth factor. In addition, the results suggest a possible involvement of bFGF in platelet function as well as in megakaryocytopoiesis. 相似文献
438.
Oestmann JW; Kopans DB; Linetsky L; Hall DA; McCarthy KA; White G; Swann C; Kelley JE; Johnson LL 《Radiology》1988,168(3):657-659
A new dual-screen, dual-emulsion-film combination that allows a decrease in radiation dose of approximately 66% was compared with a widely used single-screen, single-emulsion-film system in contact and magnification mammography. Clustered microcalcifications randomly superimposed on a breast phantom were detected, and the location and number of individual calcifications were determined by four observers. The detectability of calcifications, determined with a receiver operating characteristic (ROC) analysis area, was 0.92 for magnification and 0.82 for contact mammography with the single-emulsion-film system, compared with 0.84 and 0.72, respectively, with the dual-emulsion-film system. More clusters were correctly located and more individual calcifications were counted with magnification than with contact mammography. The dual-emulsion-film system with the magnification technique performs as well as the single-emulsion-film system with the contact technique, while retaining a decrease in required dose of approximately 40%. 相似文献
439.
高效液相色谱法对四种双氯灭痛软膏剂透皮效果的研究 总被引:2,自引:0,他引:2
目的:本实验采用高效液相色谱法,以离体小白鼠腹部皮肤为透皮屏障,比较了四种双氯灭痛软膏剂的透皮效果,方法:实验用法国Gilson公司的HPLC仪,以C18为固定相,甲醇-水(含HAc 0.36%)=80:20为流动相,紫外检测波长280nm。平均回收率为99.59%,RSD<3.28%,检测限为1.0ug/ml。结果:1号样品透皮率最高,3号与1号相比较透皮吸收无显著性差异(P>0.05),2号或4号分别与1号相比,其透皮吸收均有显著性差异(P<0.05),结论:1号品值得进一步开发。 相似文献