全文获取类型
收费全文 | 20694篇 |
免费 | 2082篇 |
国内免费 | 1727篇 |
专业分类
耳鼻咽喉 | 190篇 |
儿科学 | 283篇 |
妇产科学 | 298篇 |
基础医学 | 2119篇 |
口腔科学 | 527篇 |
临床医学 | 2542篇 |
内科学 | 2654篇 |
皮肤病学 | 196篇 |
神经病学 | 840篇 |
特种医学 | 702篇 |
外国民族医学 | 10篇 |
外科学 | 2136篇 |
综合类 | 4205篇 |
现状与发展 | 2篇 |
一般理论 | 1篇 |
预防医学 | 1634篇 |
眼科学 | 658篇 |
药学 | 2341篇 |
31篇 | |
中国医学 | 1514篇 |
肿瘤学 | 1620篇 |
出版年
2024年 | 87篇 |
2023年 | 358篇 |
2022年 | 876篇 |
2021年 | 1052篇 |
2020年 | 882篇 |
2019年 | 709篇 |
2018年 | 737篇 |
2017年 | 672篇 |
2016年 | 614篇 |
2015年 | 989篇 |
2014年 | 1122篇 |
2013年 | 1137篇 |
2012年 | 1668篇 |
2011年 | 1712篇 |
2010年 | 1209篇 |
2009年 | 1050篇 |
2008年 | 1259篇 |
2007年 | 1158篇 |
2006年 | 1141篇 |
2005年 | 1072篇 |
2004年 | 818篇 |
2003年 | 850篇 |
2002年 | 752篇 |
2001年 | 556篇 |
2000年 | 438篇 |
1999年 | 353篇 |
1998年 | 224篇 |
1997年 | 188篇 |
1996年 | 155篇 |
1995年 | 123篇 |
1994年 | 125篇 |
1993年 | 70篇 |
1992年 | 80篇 |
1991年 | 65篇 |
1990年 | 51篇 |
1989年 | 25篇 |
1988年 | 34篇 |
1987年 | 38篇 |
1986年 | 21篇 |
1985年 | 23篇 |
1984年 | 2篇 |
1983年 | 5篇 |
1982年 | 1篇 |
1980年 | 1篇 |
1979年 | 1篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
101.
Xing Chen Guixiang Wu Jing Qing Chunlin Li Xudong Chen Jian Shen 《Journal of clinical laboratory analysis》2022,36(5)
ObjectiveThis study intended to explore the regulatory functions of LINC00240 on nasopharyngeal carcinoma (NPC).MethodsMiR‐26a‐5p inhibitor, mimic, and siLINC00240 were transfected into NPC cells. QRT‐PCR was employed to assess miR‐26a‐5p and LINC00240 expressions. The targeting relationship of LINC00240 and miR‐26a‐5p was analyzed through dual luciferase reporter and RNA immunoprecipitation assay. Cell counting kit‐8 assay, colony formation assay, flow cytometry assay, wound healing assay, Transwell assay and in vitro angiogenesis assay were adopted for the evaluation of the effects of LINC00240 or miR‐26a‐5p and LINC00240 on NPC cells regarding cell proliferation, apoptosis and cycle, migration, invasion, and angiogenesis. EZH2, cell cycle, and epithelial‐mesenchymal transition (EMT)‐related protein expression was tested through Western blot.ResultsLINC00240 had a high expression in NPC tissues and cell lines. Silenced LINC00240 significantly suppressed the 5‐8F and HK1 cell proliferation, invasion, migration, and angiogenesis, but raised cell apoptosis, and cells were blocked in G0/G1 phase. MiR‐26a‐5p was a target of LINC00240. MiR‐26a‐5p upregulation suppressed the NPC cell proliferation, migration, invasion, angiogenesis, N‐cadherin and EZH2 expression, while it elevated apoptosis and p21, p27 and E‐cadherin expressions, whereas miR‐26a‐5p downregulation performed conversely. LINC00240 knockdown partially offset the effects of miR‐26a‐5p downregulation on cell proliferation, migration, invasion, angiogenesis, apoptosis, and EZH2.ConclusionLINC00240 knockdown restrained cell proliferation, invasion, migration, and angiogenesis, while it advanced apoptosis via miR‐26a‐5p in NPC by EZH2 inhibition. 相似文献
102.
根据"男性生殖健康"概念以及目前对于亚健康诊断的诸多标准,首次提出"男性生殖亚健康"概念,从病因、症状(男性生殖细胞数量下降、性功能减退、男性更年期综合征、前列腺亚健康态)等方面作出分析,并从中医理论"肾藏精、主生殖"入手.阐述男性生殖亚健康的发生机制重在肾的阴阳失衡、精气不足,临床治疗应遵循"治未病"的思想,以防为主,防治结合,"以肾为本"干预男性生殖亚健康. 相似文献
103.
Wei Wang Yongkui Yu Haibo Sun Zongfei Wang Yan Zheng Guanghui Liang Peinan Chen Jiwei Cheng Xiaoxia Xu Funa Yang Qi Liu Weiqun Xing 《Journal of gastrointestinal oncology.》2022,13(2):488
BackgroundPostoperative pneumonia (PP) is the most common pulmonary complication of esophagectomy. It is of great importance to identify any high-risk factors and prevent pulmonary complications to improve the prognosis of patients with esophageal cancer undergoing esophagectomy. Thus, we established a predictive model of PP in patients with neoadjuvant immunochemotherapy for resectable esophageal squamous cell carcinoma (ESCC), and provide suggestions for the best strategy for the perioperative period of the patients.MethodWe retrospectively analyzed 78 patients who underwent esophagectomy for squamous cell carcinoma after neoadjuvant immunochemotherapy between September 2019 and August 2021.We used the “glmnet” language package in R to perform least absolute shrinkage and selection operator (LASSO) regression to screen the best predictors of PP, and nomograms predicting PP were constructed utilizing screened factors. The performance of nomograms was internally validated by calibration curves, concordance index (C-index), and the Brier score for overall performance.ResultsTwenty-six patients (33.3%) had postoperative pneumonia. After LASSO regression, the factors that were independently associated with PP were diffusing capacity of the lungs for carbon monoxide (DLCO) (P=0.0002), white blood cell (WBC) difference before vs. after neoadjuvant immunochemotherapy (P=0.0133). We constructed a prediction model, plotted the nomogram, and verified its accuracy. Its Brier score was 0.147, its calibration slope was 0.98, and its C-index was 0.85 (95% CI: 0.75–0.95). Internal validation demonstrated a good discrimination power that the actual probability corresponds closely with the predicted probability.ConclusionsOur prediction model can predict the possibility of PP in patients with neoadjuvant immunochemotherapy for resectable esophageal squamous cell carcinoma and may facilitate physicians’ efforts to reduce the incidence of postoperative pneumonia. 相似文献
104.
105.
106.
神经再生素对皮层细胞基因表达影响的基因芯片研究 总被引:6,自引:0,他引:6
目的:采用基因芯片技术,观察神经再生素对体外培养的胚鼠大脑皮质细胞基因表达的影响。方法:取ICR胚鼠(15d)大脑皮层细胞,无血清培养。实验组加入神经再生素(2μg/ml),对照组加入等量基础培养液。培养6h后,抽提实验组和对照组皮层细胞总RNA,经反转录分别用Cy5、Cy3荧光标记成cDNA探针。将荧光标记的cDNA与MGEC-40s基因表达谱芯片杂交,芯片扫描、数据处理。结果:实验组与对照组大脑皮质细胞出现64条差异性表达的基因。呈现上调的基因有:钙调素结合蛋白、锌指蛋白激酶、核糖体蛋白等基因;下调基因有:抑制细胞分裂因子等基因。结论:神经再生素可作用于体外培养的胚鼠大脑皮层细胞,从基因调控水平促进脑细胞生长。 相似文献
107.
龙胆苦苷在人尿中的含量测定及排泄研究 总被引:5,自引:0,他引:5
目的:建立固相萃取液质联用方法测定人尿中龙胆苦苷浓度,研究人体静脉滴注注射用秦龙苦素的主要代谢途径。方法:尿样加入咖啡因内标,经固相萃取后LC-MS/MS分析。色谱条件为:Rescek C8柱(150 mm×2.1 mm,5μm),流动相为:甲醇-10 mmol/L醋酸铵缓冲液-乙腈(50∶40∶10),流速为0.2 mL/min,质谱检测采用多反应离子监测方式。12名健康受试者随机分组交叉静脉滴注80,240,400 mg药物,用本法测定各时段尿样的浓度。结果:龙胆苦苷在30~9 000 ng/mL线性良好(r=0.998 0),回收率为91.10%~96.21%,提取回收率为100.52%~103.83%,高、中、低浓度日内和日间变异系数均小于10%;24 h内3个剂量下原形药物在尿中累积排泄率分别为(76.59±10.02)%、(71.95±12.12)%、(79.76±8.54)%,累积排泄量与给药剂量呈正比,排泄高峰为0~5.5 h。结论:本方法适用于临床药物动力学研究,注射用秦龙苦素在人体内主要是以原形龙胆苦苷经肾脏排泄。 相似文献
108.
109.
110.