全文获取类型
收费全文 | 27312篇 |
免费 | 2779篇 |
国内免费 | 2057篇 |
专业分类
耳鼻咽喉 | 165篇 |
儿科学 | 235篇 |
妇产科学 | 246篇 |
基础医学 | 3219篇 |
口腔科学 | 420篇 |
临床医学 | 3780篇 |
内科学 | 3899篇 |
皮肤病学 | 249篇 |
神经病学 | 1469篇 |
特种医学 | 1394篇 |
外国民族医学 | 18篇 |
外科学 | 2864篇 |
综合类 | 4804篇 |
现状与发展 | 12篇 |
一般理论 | 4篇 |
预防医学 | 1899篇 |
眼科学 | 676篇 |
药学 | 2817篇 |
35篇 | |
中国医学 | 1703篇 |
肿瘤学 | 2240篇 |
出版年
2024年 | 111篇 |
2023年 | 505篇 |
2022年 | 1342篇 |
2021年 | 1668篇 |
2020年 | 1271篇 |
2019年 | 1108篇 |
2018年 | 1061篇 |
2017年 | 957篇 |
2016年 | 916篇 |
2015年 | 1270篇 |
2014年 | 1661篇 |
2013年 | 1475篇 |
2012年 | 2100篇 |
2011年 | 2220篇 |
2010年 | 1391篇 |
2009年 | 1083篇 |
2008年 | 1300篇 |
2007年 | 1321篇 |
2006年 | 1267篇 |
2005年 | 1217篇 |
2004年 | 789篇 |
2003年 | 835篇 |
2002年 | 762篇 |
2001年 | 613篇 |
2000年 | 596篇 |
1999年 | 593篇 |
1998年 | 410篇 |
1997年 | 407篇 |
1996年 | 286篇 |
1995年 | 277篇 |
1994年 | 241篇 |
1993年 | 174篇 |
1992年 | 154篇 |
1991年 | 147篇 |
1990年 | 94篇 |
1989年 | 92篇 |
1988年 | 106篇 |
1987年 | 86篇 |
1986年 | 43篇 |
1985年 | 40篇 |
1984年 | 29篇 |
1983年 | 20篇 |
1982年 | 24篇 |
1981年 | 19篇 |
1980年 | 12篇 |
1979年 | 11篇 |
1978年 | 5篇 |
1977年 | 9篇 |
1976年 | 18篇 |
1975年 | 7篇 |
排序方式: 共有10000条查询结果,搜索用时 33 毫秒
31.
鸡贫血病毒VP 3基因的克隆及其体外凋亡诱导效应的研究 总被引:1,自引:0,他引:1
用PCR方法扩增了鸡贫血病毒标准株的vp3基因,并将其克隆于真核表达载体pcDNA3上,构建了重组体pcDNA-vp3.经酶切鉴定及测序分析表明,该片段和预期相符.在体外利用LipofectAMINETM介导的基因转染,将pc-DNA-vp3、pcDNA3分别转入肝癌细胞系HepG2和二倍体肝细胞系L-02中,转染后的RT-PCR结果证实vp3基因在细胞中得到了表达.同时利用筛选稳定表达细胞株的技术和原位细胞凋亡检测法,证明了鸡贫血病毒是以凋亡的方式诱导细胞死亡,并且只诱导癌细胞的凋亡,而不诱导正常或二倍体细胞死亡.表明鸡贫血病毒vp3基因很可能成为一种极具潜力的抗肿瘤生物制剂. 相似文献
32.
Yi Lu Jia Tian Shangren Wang Xiao Wang Yuxuan Song Kang Liu Kechong Zhou Yongjiao Yang Xiaoqiang Liu 《Andrologia》2021,53(5):e14038
The study was designed and conducted to evaluate the plant-based diet status and its association with erectile function (EF) in Chinese young healthy men. From July 2018 to May 2020, 116 objectively proved physically and psychologically healthy men were selected. Clinical questionnaires, detailed physical examinations and blood tests were all assessed. An overall plant-based diet index (PDI) and a healthful plant-based diet index (hPDI) were developed from each participant to measure plant-based diet quantitatively. The EF was measured by both the International Index of Erectile Function-5 (IIEF-5) and the surrogated measures of endothelial function, peripheral levels of nitric oxide (NO) and E-selectin. In subjects, the mean PDI and hPDI were 53.8 ± 8.2 and 54.7 ± 8.9 respectively. Results of multivariate analysis showed that both PDI and hPDI were negatively associated with BMI (all p < .05), but had no relationships with NO, E-selectin, TT levels and IIEF-5 scores (all p > .05). In a subgroup of male population, Chinese young healthy men, the plant-based diet, measured by PDI and hPDI, was not related to erectile function. The population can adhere to plant-based diet to keep healthy without concerns of negative influence on erectile function. 相似文献
33.
34.
Effects of bariatric surgery on patients with obesity and polycystic ovary syndrome: a meta-analysis
Zhao Tian Yi-Chao Zhang Yue Wang Xiao-Hong Chang Hong-Lan Zhu Yan Zhao 《Surgery for obesity and related diseases》2021,17(8):1399-1408
BackgroundBariatric surgery is effective for polycystic ovary syndrome (PCOS), while the exact mechanism remains unclear.ObjectivesTo assess the impact of bariatric surgery on PCOS patients and further explore the possible mechanism.SettingA meta-analysis.MethodsWe searched PubMed, Web of Science, The Cochrane Library, and Embase to identify relevant studies published before November 2020.ResultsTwenty-one studies met our inclusion criteria, and we identified 552 patients with PCOS study. Results showed that the prevalence of preoperative PCOS, menstrual irregularity, hirsutism, type 2 diabetes (T2D), hypertension, infertility, and depression significantly decreased after bariatric surgery. Levels of total testosterone, fasting insulin, and luteinizing hormone (LH) decreased and estradiol increased, while levels of follicle-stimulating hormone (FSH) and LH/FSH did not show significant changes during the 3-month follow-up. There were decreases in testosterone and fasting insulin levels when the postoperative follow-up time was 6 months or ≥12 months. Levels of fasting blood glucose and triglycerides were significantly reduced after 6 months or ≥12 months of bariatric surgery. High-density lipoprotein (HDL) and sex hormone-binding globulin (SHBG) significantly improved ≥12 months after bariatric surgery.ConclusionSymptoms of PCOS and related complications are significantly alleviated after bariatric surgery. In addition, we found a significant improvement on anomalous secretion of gonadotropins, glucose metabolism, and lipid metabolism in patients with PCOS after bariatric surgery. 相似文献
35.
36.
37.
38.
5 Gy全身照射对大鼠伤口巨噬细胞的抑制效应及W11-a12的促愈作用 总被引:2,自引:1,他引:1
目的 研究大鼠全身5Gy照射对伤口巨噬细胞(MΦ)功能的影响及W11-a12的促愈作用。方法 采用^60Coγ射线身身照射复合皮肤创伤模型,观察了MΦ酵母-补体复合物玫瑰花环形成试验、吞噬功能和分泌纤维粘连蛋白(FN)、转化生长因子β1(TGFβ1)、碱性成纤维细胞生长因子(bFGF)的功能。结果 大鼠5Gy全身照射复合皮肤创伤后第3、5天伤口内巨噬细胞C3b受体表达、吞噬功能,合成与分泌FN、TGFβ、bFGF的功能均显著受到抑制,但抑制效应的程度不同,MΦ的吞噬功能的抑制重于其分泌功能,分泌TGFβ1功能的抑制重于分泌bFGF的功能,W11-a12能显著逆转辐射对MΦ功能的抑制效应。结论 伤口MΦ功能受抑是合并放射损伤后伤口难愈的主要原因,增强MΦ功能是W11-a12促愈作用的一个途径。 相似文献
39.
田新强 《大同医学专科学校学报》2000,20(1):5-9
为了解心肌容量负荷是否影响心肌的氧化磷酸化过程,采用兔离体灌流心肌线粒体氧耗反应时间测定方法,对一下正常心室容量负荷和低心室容量负荷时的心肌线粒体氧耗反应时间进行比较,结果提示心肌作功负荷变化未能影响心肌线粒体的能量代谢动态调节过程。 相似文献
40.
Acute pancreatitis ( AP) is a common surgicalabdomen,which has a high mortality,especiallyhemorrhagic necrotic pancreatitis.Many things areunknown for its pathogen,pathogenesis and clinicaltreatment.Restraining secretion of pancreatin so asto decrease its complication is used now in clinicalpractice[1] .A lot of information indicates that vagushas directdomination on exocrine of pancreas[2 ] .Thepurpose of this study was to investigate whether thevagotomy ( VG) had effect on AP in rats.1 M… 相似文献