全文获取类型
收费全文 | 71383篇 |
免费 | 6857篇 |
国内免费 | 4948篇 |
专业分类
耳鼻咽喉 | 409篇 |
儿科学 | 728篇 |
妇产科学 | 900篇 |
基础医学 | 8908篇 |
口腔科学 | 1206篇 |
临床医学 | 9581篇 |
内科学 | 10831篇 |
皮肤病学 | 800篇 |
神经病学 | 3763篇 |
特种医学 | 2465篇 |
外国民族医学 | 41篇 |
外科学 | 7433篇 |
综合类 | 12188篇 |
现状与发展 | 17篇 |
一般理论 | 2篇 |
预防医学 | 4374篇 |
眼科学 | 1871篇 |
药学 | 7572篇 |
103篇 | |
中国医学 | 3888篇 |
肿瘤学 | 6108篇 |
出版年
2025年 | 17篇 |
2024年 | 1017篇 |
2023年 | 1593篇 |
2022年 | 3031篇 |
2021年 | 3757篇 |
2020年 | 2851篇 |
2019年 | 2458篇 |
2018年 | 2447篇 |
2017年 | 2115篇 |
2016年 | 2130篇 |
2015年 | 3204篇 |
2014年 | 4003篇 |
2013年 | 3310篇 |
2012年 | 4846篇 |
2011年 | 5710篇 |
2010年 | 3299篇 |
2009年 | 2508篇 |
2008年 | 3454篇 |
2007年 | 3536篇 |
2006年 | 3619篇 |
2005年 | 3458篇 |
2004年 | 2240篇 |
2003年 | 2207篇 |
2002年 | 1843篇 |
2001年 | 1695篇 |
2000年 | 1775篇 |
1999年 | 1968篇 |
1998年 | 1256篇 |
1997年 | 1346篇 |
1996年 | 1012篇 |
1995年 | 892篇 |
1994年 | 769篇 |
1993年 | 494篇 |
1992年 | 603篇 |
1991年 | 522篇 |
1990年 | 446篇 |
1989年 | 393篇 |
1988年 | 326篇 |
1987年 | 283篇 |
1986年 | 249篇 |
1985年 | 174篇 |
1984年 | 102篇 |
1983年 | 71篇 |
1982年 | 38篇 |
1981年 | 52篇 |
1980年 | 28篇 |
1979年 | 40篇 |
1963年 | 1篇 |
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
151.
152.
Zhao Liu Sizhe Cao Changsheng Zhu Lin Wei Huijun Zhang Qian Li 《Annals of thoracic and cardiovascular surgery》2015,21(6):523-528
Background: To investigate the efficacy and value of thoracoscopic hybrid surgery in the treatment of stage III chronic tuberculous empyema (CTE).Methods: 48 patients diagnosed as CTE with pleural thickening and encysted abscess cavity from were treated by hybrid operation (HO). Small incision operation was first used for resection of thickening pleural fibreboard and decortication of parietal pleura. Then, thoracoscopy was guided into chest to decorticate the visceral pleurali. Additional 25 patients with open operation of pleurectomy were set as control.Results: The average operation time of HO group was 70 ± 22 min compared to 130 ± 32 min of control. The amount of bleeding, hospitalization time and chest tube drainage of HO group (200 ± 55 ml, 18 ± 1.2 days, 3.5 ± 1.5 days) were significantly decreased compared to control (400 ± 45 ml, 28 ± 4.5 days, 6.5 ± 2.5 days). Post operation complications occurred in 5 (10.42%) and 3 (12%) cases for HO group and control, respectively.Conclusions: In stage III CTE, the small incision assisted thoracoscopic hybrid surgery help to remove thickening parietal pleura, promote the application of thoracoscopy, which has obvious advantages compared to traditional surgery. 相似文献
153.
154.
155.
Zhendong Zhu Jiyun Ye Yumei Ma Peng Hua Yu Huang Xuemei Fu Dexuan Li Maogen Yuan Zhonghua Xia 《Human immunology》2018,79(7):564-570
T regulatory type 1 (Tr1) cells can promote tolerance and suppress inflammation. Atherosclerosis may be induced by the proinflammatory activation of cells in the vasculature and the immune system. Hence, we wondered whether defects in Tr1 function were a contributing factor to coronary artery disease (CAD). Data showed that the frequency of IL-10+ Tr1 cells was significantly lower in CAD patients than in controls. Compared to healthy controls, Tr1 cells from CAD patients presented lower CTLA-4 but higher PD-1 expression, in addition to lower IL-10 secretion. When co-incubated with Tconv cells, the CD4+CD49b+LAG-3+CD45RO+ Tr1 cells presented IL-10-dependent inhibitory effects, and those from CAD patients presented significantly lower suppression capacity than those from healthy controls. Interestingly, the characteristics of Tr1 cells were associated with clinical features of CAD patients. The frequency of Tr1 cells and the IL-10 and LAG-3 expression by Tr1 cells were negatively correlated with the BMI of the CAD patients. In addition, the Tr1 frequency and the LAG-3 and CTLA-4 expression on Tr1 cells were lower in CAD patients with higher numbers of narrowed vessels. Together, these results suggest that in CAD, Tr1 cells present multiple defects, which are associated with the clinical presentation of the disease. 相似文献
156.
Acute respiratory distress syndrome (ARDS) is a rapid onset life-threatening condition involving uncontrolled propagation of inflammatory responses. Here, we observed that ARDS patients that survived presented significantly higher frequencies of TIM-1+ B cells, especially the CD27+TIM-1+ B cells, than the ARDS patients who succumbed to the condition. We then found that using BCR/CD40 antigen-dependent stimulation or Staphylococcus aureus Cowan (SAC) antigen-independent stimulation, TIM-1+ B cells presented significantly higher IL-10 secretion and/or TGF-β1 secretion, with SAC stimulation being more effective. CD4+ T cells that incubated with TIM-1+ B cells presented significantly elevated IL-10 secretion, TGF-β1 secretion, and Foxp3 expression, than CD4+ T cells that incubated with TIM-1? B cells, suggesting TIM-1+ B cells promoted the in vitro development of Foxp3+ Treg cells. Interestingly, this TIM-1+ B cell-mediated promotion of Foxp3 expression was mostly dependent on TGF-β1 but not IL-10, since neutralization of TGF-β1, but not IL-10, resulted in the suppression of Foxp3 expression. We further showed that in TIM-1+ B cells, the CD27+ classical memory B cell subset demonstrated more regulatory potency than the CD27? subset. Together, our results suggested that the TIM-1+ B cells, especially those that expressed CD27, could promote Foxp3 expression. Their clinical efficacy in treating ARDS should be examined in in vivo experiments. 相似文献
157.
158.
159.
160.
Hydrolytic Stability of Methacrylamide and Methacrylate in Gelatin Methacryloyl and Decoupling of Gelatin Methacrylamide from Gelatin Methacryloyl through Hydrolysis 下载免费PDF全文
Jing Zheng Mengxiang Zhu Gaia Ferracci Nam‐Joon Cho Bae Hoon Lee 《Macromolecular chemistry and physics.》2018,219(18)
Gelatin methacryloyl (GelMA; GM) is a promising nature‐derived photocurable material that can mimic the extracellular matrix because GelMA features tailorable mechanical properties, proteolytic degradation, and good cell adhesion. GelMA contains not only methacrylamide but also methacrylate. However, the hydrolytic stability of methacrylamide and methacrylate groups of GelMA in aqueous solutions has not been scrutinized. Here, the structural change of GelMA through hydrolysis is investigated for the first time. The structural change of hydrolyzed GelMA is quantitatively identified using colorimetric and 1H NMR methods. The methacrylate groups decompose markedly at high pH solutions, but the methacrylamide groups remain stable. Further, pure gelatin methacrylamide is successfully decoupled from GelMA for a better understanding of GelMA structure and future use for biomedical applications. 相似文献