首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   127923篇
  免费   48215篇
  国内免费   1679篇
耳鼻咽喉   2009篇
儿科学   5430篇
妇产科学   1709篇
基础医学   21412篇
口腔科学   6200篇
临床医学   18350篇
内科学   33404篇
皮肤病学   8435篇
神经病学   16216篇
特种医学   3372篇
外国民族医学   6篇
外科学   19817篇
综合类   6192篇
现状与发展   2篇
一般理论   30篇
预防医学   8951篇
眼科学   2485篇
药学   10430篇
  52篇
中国医学   3288篇
肿瘤学   10027篇
  2024年   148篇
  2023年   700篇
  2022年   1578篇
  2021年   3943篇
  2020年   6796篇
  2019年   12376篇
  2018年   11891篇
  2017年   13000篇
  2016年   13364篇
  2015年   13880篇
  2014年   14518篇
  2013年   15487篇
  2012年   9023篇
  2011年   9009篇
  2010年   12177篇
  2009年   8095篇
  2008年   5638篇
  2007年   4422篇
  2006年   3986篇
  2005年   3498篇
  2004年   2846篇
  2003年   2743篇
  2002年   2466篇
  2001年   1309篇
  2000年   1144篇
  1999年   643篇
  1998年   319篇
  1997年   291篇
  1996年   257篇
  1995年   214篇
  1994年   180篇
  1993年   144篇
  1992年   190篇
  1991年   133篇
  1990年   138篇
  1989年   113篇
  1988年   104篇
  1987年   93篇
  1986年   104篇
  1985年   84篇
  1984年   69篇
  1983年   65篇
  1982年   73篇
  1981年   73篇
  1980年   37篇
  1979年   52篇
  1978年   29篇
  1977年   38篇
  1976年   42篇
  1975年   29篇
排序方式: 共有10000条查询结果,搜索用时 93 毫秒
81.
A pathological feature in atherosclerosis is the dysfunction and death of vascular endothelial cells (EC). Oxidized low‐density lipoprotein (LDL), known to accumulate in the atherosclerotic arterial walls, impairs endothelium‐dependent relaxation and causes EC apoptosis. A major bioactive ingredient of the oxidized LDL is lysophosphatidylcholine (LPC), which at higher concentrations causes apoptosis and necrosis in various EC. There is hitherto no report on LPC‐induced cytotoxicity in brain EC. In this work, we found that LPC caused cytosolic Ca2+ overload, mitochondrial membrane potential decrease, p38 activation, caspase 3 activation and eventually apoptotic death in mouse cerebral bEND.3 EC. In contrast to reported reactive oxygen species (ROS) generation by LPC in other EC, LPC did not trigger ROS formation in bEND.3 cells. Pharmacological inhibition of p38 alleviated LPC‐inflicted cell death. We examined whether heparin could be cytoprotective: although it could not suppress LPC‐triggered Ca2+ signal, p38 activation and mitochondrial membrane potential drop, it did suppress LPC‐induced caspase 3 activation and alleviate LPC‐inflicted cytotoxicity. Our data suggest LPC apoptotic death mechanisms in bEND.3 might involve mitochondrial membrane potential decrease and p38 activation. Heparin is protective against LPC cytotoxicity and might intervene steps between mitochondrial membrane potential drop/p38 activation and caspase 3 activation.  相似文献   
82.
While therapeutic approaches for psoriasis are widely available, preventive regimens are lacking. We aimed to determine whether improvements in epidermal function could prevent psoriasis relapse. Two self‐controlled cohort studies were designed, enrolling two cohorts of patients with psoriasis (n = 30 and n = 60) to be treated topically with an in‐house‐prepared emollient or ATOPALM® cream applied twice daily to one forearm for 20 and 30 days, respectively, while the same sites on the contralateral arm served as the untreated control. Epidermal function on both arms was assessed prior to and at the end of the trials. Delayed relapse on the treated arm was seen in 54.5% and 71% of patients in the first and second cohort, respectively. The time of psoriatic relapse correlated with the extent of abnormalities in baseline epidermal function. These results suggest that improvements in epidermal function with topical emollients can prevent/attenuate the development of psoriasis.  相似文献   
83.
84.
85.
Gastric cancer, one of the most common disease, has become a major public health problem worldwide. Cisplatin (DDP) has been a widely used drug for the treatment of cancer, also usually applied in gastric cancer in clinic. However, the side effects including toxicity and drug-resistance restricted the usage of DDP in clinic, so we prepared a DDP-complexed hydrogel (DDP-Gel) and investigated its efficacy in gastric cancer. For in vivo studies, MKN45-Luc cells were injected into BLAB/C node mice subcutaneously to establish gastric cancer with orthotopically grown tumors. Mice bearing tumors were treated with normal saline, DDP and DDP-Gel. Body weight and survival condition were observed and recorded. The treatment efficacy in vivo was detected by luciferase imaging and histological evaluation was performed by H&E staining of different organs. Additionally, normal ICR mice were treated with different doses of DDP/DDP-Gel to calculate their LD50 in vivo. The results showed that DDP-Gel prolonged survival time and ameliorated body weight changes of mice bearing tumors. DDP-Gel exhibited higher efficacy to inhibit tumor growth and metastasis, compared to DDP. Besides, LD50 of DDP-Gel was 166.0?mg/kg, 13.2 folds higher than DDP. As a conclusion, DDP-Gel showed a more effective and safer function than DDP in gastric cancer, which indicating that DDP-Gel might be a novel strategy for gastric cancer therapy.  相似文献   
86.
87.
88.
89.
First described in 1955 in New Jersey, epizootic haemorrhagic disease (EHD) causes a severe clinical disease in wild and domestic ruminants worldwide. Epizootic haemorrhagic disease outbreaks occur in deer populations each year from summer to late autumn. The etiological agent is EHD virus (EHDV) which is a double‐stranded segmented icosahedral RNA virus. EHD virus utilizes point mutations and reassortment strategies to maintain viral fitness during infection. In 2018, EHDV serotype 2 was predominantly detected in deer in Illinois. Whole genome sequencing was conducted for two 2018 EHDV2 isolates (IL41747 and IL42218) and the sequence analyses indicated that IL42218 was a reassortant between different serotypes whereas IL41747 was a genetically stable strain. Our data suggest that multiple strains contribute to outbreaks each year.  相似文献   
90.
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号