全文获取类型
收费全文 | 2216篇 |
免费 | 202篇 |
国内免费 | 33篇 |
专业分类
耳鼻咽喉 | 7篇 |
儿科学 | 79篇 |
妇产科学 | 40篇 |
基础医学 | 218篇 |
口腔科学 | 56篇 |
临床医学 | 198篇 |
内科学 | 421篇 |
皮肤病学 | 279篇 |
神经病学 | 94篇 |
特种医学 | 305篇 |
外科学 | 262篇 |
综合类 | 29篇 |
预防医学 | 132篇 |
眼科学 | 111篇 |
药学 | 101篇 |
中国医学 | 8篇 |
肿瘤学 | 111篇 |
出版年
2023年 | 15篇 |
2022年 | 21篇 |
2021年 | 58篇 |
2020年 | 51篇 |
2019年 | 54篇 |
2018年 | 66篇 |
2017年 | 56篇 |
2016年 | 75篇 |
2015年 | 47篇 |
2014年 | 65篇 |
2013年 | 78篇 |
2012年 | 82篇 |
2011年 | 115篇 |
2010年 | 80篇 |
2009年 | 60篇 |
2008年 | 68篇 |
2007年 | 88篇 |
2006年 | 80篇 |
2005年 | 58篇 |
2004年 | 66篇 |
2003年 | 74篇 |
2002年 | 61篇 |
2001年 | 58篇 |
2000年 | 47篇 |
1999年 | 37篇 |
1998年 | 72篇 |
1997年 | 78篇 |
1996年 | 83篇 |
1995年 | 58篇 |
1994年 | 47篇 |
1993年 | 46篇 |
1992年 | 26篇 |
1991年 | 20篇 |
1990年 | 25篇 |
1989年 | 46篇 |
1988年 | 47篇 |
1987年 | 40篇 |
1986年 | 39篇 |
1985年 | 41篇 |
1984年 | 17篇 |
1983年 | 16篇 |
1982年 | 13篇 |
1981年 | 14篇 |
1980年 | 20篇 |
1979年 | 12篇 |
1978年 | 14篇 |
1977年 | 19篇 |
1976年 | 12篇 |
1975年 | 8篇 |
1971年 | 12篇 |
排序方式: 共有2451条查询结果,搜索用时 15 毫秒
1.
Isolated patellofemoral arthritis is an increasingly recognized entity, and is usually associated with previous patellofemoral dysplasia or instability. Patellofemoral arthroplasty (PFA) has evolved significantly in recent years, both in terms of implant design and importantly in the understanding of appropriate patient selection. This review outlines the indications and investigations for PFA, provides a brief history of the development of contemporary implants, and presents the clinical outcomes for the prostheses most commonly used in the UK. In addition, it provides a detailed surgical technique for implantation of an onlay implant, with tips on how to optimize patellofemoral biomechanics and thus achieve a consistently good outcome. 相似文献
2.
Julie A. Schmidt Georgina K. Fensom Sabina Rinaldi Augustin Scalbert Paul N. Appleby David Achaintre Audrey Gicquiau Marc J. Gunter Pietro Ferrari Rudolf Kaaks Tilman Kühn Heiner Boeing Antonia Trichopoulou Anna Karakatsani Eleni Peppa Domenico Palli Sabina Sieri Rosario Tumino Bas Bueno-de-Mesquita Antonio Agudo Maria-Jose Sánchez María-Dolores Chirlaque Eva Ardanaz Nerea Larrañaga Aurora Perez-Cornago Nada Assi Elio Riboli Konstantinos K. Tsilidis Timothy J. Key Ruth C. Travis 《International journal of cancer. Journal international du cancer》2020,146(3):720-730
Metabolomics may reveal novel insights into the etiology of prostate cancer, for which few risk factors are established. We investigated the association between patterns in baseline plasma metabolite profile and subsequent prostate cancer risk, using data from 3,057 matched case–control sets from the European Prospective Investigation into Cancer and Nutrition (EPIC). We measured 119 metabolite concentrations in plasma samples, collected on average 9.4 years before diagnosis, by mass spectrometry (AbsoluteIDQ p180 Kit, Biocrates Life Sciences AG). Metabolite patterns were identified using treelet transform, a statistical method for identification of groups of correlated metabolites. Associations of metabolite patterns with prostate cancer risk (OR1SD) were estimated by conditional logistic regression. Supplementary analyses were conducted for metabolite patterns derived using principal component analysis and for individual metabolites. Men with metabolite profiles characterized by higher concentrations of either phosphatidylcholines or hydroxysphingomyelins (OR1SD = 0.77, 95% confidence interval 0.66–0.89), acylcarnitines C18:1 and C18:2, glutamate, ornithine and taurine (OR1SD = 0.72, 0.57–0.90), or lysophosphatidylcholines (OR1SD = 0.81, 0.69–0.95) had lower risk of advanced stage prostate cancer at diagnosis, with no evidence of heterogeneity by follow-up time. Similar associations were observed for the two former patterns with aggressive disease risk (the more aggressive subset of advanced stage), while the latter pattern was inversely related to risk of prostate cancer death (OR1SD = 0.77, 0.61–0.96). No associations were observed for prostate cancer overall or less aggressive tumor subtypes. In conclusion, metabolite patterns may be related to lower risk of more aggressive prostate tumors and prostate cancer death, and might be relevant to etiology of advanced stage prostate cancer. 相似文献
3.
4.
Sonoelasticity imaging of prostate cancer: in vitro results 总被引:2,自引:0,他引:2
5.
6.
7.
8.
9.
Ten thrombocytopenic patients (platelets < 10–24 × 10(9)/L) who were refractory to platelet transfusion were investigated for their responsiveness to staphylococcal protein A column therapy. Nine patients had previously been treated with steroids, intravenous immune globulin, and/or other forms of immunosuppressive therapy without improvement in their transfusion response. All patients were receiving multiple platelet transfusions without achieving 1-hour corrected count increments (CCIs) > or = 7500. Eight patients had antibodies that reacted with platelets and were directed against HLA class I antigens, ABO antigens, and/or platelet-specific alloantigens. Plasma (500-2000 mL) from each patient was passed over a protein A silica gel column and then returned to the patient. Patients received from 1 to 14 treatments. A positive response to protein A therapy was defined as at least a doubling of the pretreatment platelet count and/or two successive 10- to 120-minute posttransfusion CCIs > or = 7500. Following plasma treatments, 6 of 10 patients responded with daily platelet counts that averaged 48 +/− 11 × 10(9) per L as compared with counts of 16 +/− 7 × 10(9) per L (p < 0.0005) before treatment. Posttransfusion CCI values determined in four of these patients averaged 2480 +/− 810 and 10,010 +/− 3540 (p < 0.005) before and after treatment, respectively. In contrast, among the four unresponsive patients, platelet counts averaged 10 +/− 9 and 13 +/− 10 × 10(9) per L (p = NS), respectively, while posttransfusion CCIs were 700 +/− 1410 and 1520 +/− 2460 (p = NS), respectively.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
10.
目的 探索LDH实验检测细胞活力的可行性。方法 原代培养骨髓细胞和软骨细胞,用LDH实验测定上述两组细胞的活力,并与镜下活体观察到细胞的生长状况相比较。与目前比较成熟的测定细胞活力的MTS实验的测得的值相比较。结果 LDH实验对上述两组细胞的活力的测定结果与镜下活体观察到的结果相符合。与MTS实验的测得的结果经统计学处理无显著差异。结论 LDH实验可用于细胞活力的直接测定,而对活细胞的生存、繁殖无影响。 相似文献