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   71327篇
  免费   5806篇
  国内免费   3277篇
耳鼻咽喉   197篇
儿科学   1328篇
妇产科学   829篇
基础医学   12700篇
口腔科学   739篇
临床医学   5546篇
内科学   16745篇
皮肤病学   1072篇
神经病学   2648篇
特种医学   1293篇
外国民族医学   9篇
外科学   3879篇
综合类   10539篇
现状与发展   19篇
预防医学   6012篇
眼科学   485篇
药学   8853篇
  18篇
中国医学   3535篇
肿瘤学   3964篇
  2023年   797篇
  2022年   1855篇
  2021年   2287篇
  2020年   2151篇
  2019年   2389篇
  2018年   2283篇
  2017年   2242篇
  2016年   2602篇
  2015年   2866篇
  2014年   4656篇
  2013年   4851篇
  2012年   4778篇
  2011年   5090篇
  2010年   4122篇
  2009年   3923篇
  2008年   3875篇
  2007年   3764篇
  2006年   3428篇
  2005年   2928篇
  2004年   2426篇
  2003年   2103篇
  2002年   1710篇
  2001年   1497篇
  2000年   1156篇
  1999年   1009篇
  1998年   926篇
  1997年   767篇
  1996年   648篇
  1995年   661篇
  1994年   565篇
  1993年   463篇
  1992年   440篇
  1991年   349篇
  1990年   318篇
  1989年   285篇
  1988年   240篇
  1987年   205篇
  1986年   170篇
  1985年   443篇
  1984年   460篇
  1983年   371篇
  1982年   379篇
  1981年   316篇
  1980年   292篇
  1979年   261篇
  1978年   205篇
  1977年   159篇
  1976年   176篇
  1975年   153篇
  1974年   126篇
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
1.
《Immunity》2022,55(7):1316-1326.e4
  1. Download : Download high-res image (134KB)
  2. Download : Download full-size image
  相似文献   
2.
Background/objectiveObstructive sleep apnea (OSA) is independently associated with dyslipidemia, a surrogate marker of atherosclerosis. Low-density lipoprotein (LDL)-cholesterol is accepted as a major independent risk factor for cardiovascular disease. However, non-high-density lipoprotein (HDL)-cholesterol is a better marker of atherogenic dyslipidemia and recommended as a target of lipid lowering therapy. We aimed to assess the prevalence of atherogenic dyslipidemia, and relationship between OSA severity and serum LDL-cholesterol and non-HDL cholesterol levels in OSA patients.MethodsWe retrospectively evaluated treatment naïve 2361 subjects admitted to the sleep laboratory of a university hospital for polysomnography. All subjects’ lipid profile including total cholesterol, LDL-cholesterol, HDL-cholesterol, triglycerides, and non-HDL-cholesterol were measured.ResultsOut of 2361 patients (mean age 49.6 ± 11.9 years; 68.9% male, apnea-hypopnea index 36.6 ± 28.4/h), 185 (7.8%) had no OSA and 2176 (92.2%) had OSA. Atherogenic dyslipidemia prevalence was high (57–66%) in OSA patients, and especially increased in severe OSA compared to other groups (p < 0.05). Though total and LDL-cholesterol did not differ between those with and without OSA, non-HDL-cholesterol (p = 0.020), and triglycerides (p = 0.001) were higher and HDL-cholesterol levels (p = 0.018) were lower in OSA patients than non-OSA. Non-HDL-cholesterol was significantly correlated with OSA severity (p < 0.001) and hypoxia parameters (p < 0.01), whereas LDL-cholesterol showed no correlation.ConclusionsAtherogenic dyslipidemia is highly prevalent and non-HDL-cholesterol levels are significantly increased, predominantly in severe OSA patients. Non-HDL-cholesterol but not LDL-cholesterol, is significantly correlated with OSA severity and hypoxia parameters. Therefore, it could be better to use non-HDL-cholesterol, which is a guideline recommended target of lipid therapy, as a marker of atherosclerotic cardiovascular risk in OSA patients.  相似文献   
3.
4.
This study aimed to observe the therapeutic effects of magnesium lithospermate B on acute and chronic colitis induced by dextran sodiumsulfate (DSS) and the role of inflammasome complex (NOD-like receptor protein, NLRP; apoptosis-associated speck-like protein containing, ASC; caspase-1). Establishment of acute and chronic colitis models were by using 5% DSS oral administration in BALB/C male mice. Magnesium lithospermate B (240 mg/kg body weight) was given by subcutaneous injection. Samples were collected for biomarker assay, histological examination, immunohistochemical evaluation and western blot. There was obvious increase in TNF-α level and NLPR3, ASC, and caspase-1 expressions in acute and chronic colitis groups compared with the normal control. Significant decrease of the tumor necrosis factor-α level and the expressions of NLPR3, ASC, and caspase-1 were observed after treatment with magnesium lithospermate B. This study showed that magnesium lithospermate B could be used to treat acute and chronic colitis by inhibiting the activation of the NLRP3/ASC/Caspase-1 pathway.  相似文献   
5.
Serum thromboxane-B2 (TxB2), together with arachidonic acid (AA)-induced platelet aggregation, are, at the moment, the most used tests to identify patients displaying high on-aspirin treatment platelet reactivity (HAPR). Both tests are specific for aspirin action on cyclooxygenase-1. While the correlation between serum TxB2 assay and clinical outcome is established, data are conflicting with regard to aspirin treatment and a possible association with AA-stimulated platelet markers and clinical outcome. To understand such discrepancy, we performed a retrospective study to compare both assays. We collected data from 132 patients receiving a daily dose of aspirin (100?mg/day) and data from 48 patients receiving aspirin on alternate days. All Patients who received a daily dose of aspirin were studied for AA-induced platelet aggregation together with serum TxB2 levels and AA-induced TxB2 formation was also studied in 71 patients out of entire population. Consistent with recommendations in the literature, we defined HAPR by setting a cut-off point at 3.1?ng/ml for serum levels of thromboxane B2 and 20% for AA-induced platelet aggregation. According to this cut-off point, we divided our overall population into two groups: (1) TxB2?<?3.1?ng/ml and (2) TxB2?>?3.1?ng/ml. We found low agreement between such tests to identify patients displaying HAPR. Our results show that AA-induced platelet aggregation >20% identify a smaller number of HAPR patients in comparison with TxB2. A good correlation between serum TxB2 and arachidonic acid-induced TxB2 production was found (r?=?0.76619).  相似文献   
6.
7.
8.
目的:分析延续护理干预对慢性乙型肝炎患者抗病毒治疗依从性的影响。方法:研究选取2017年1月~2017年12月某院肝二病区收治的112例乙型肝炎患者和2018年1月~2018年12月收治的98例乙型肝炎病毒患者作为研究对象,所有患者均进行抗病毒治疗,回顾性分析患者的病历资料。将2017年收治的112例患者作为常规组实施常规护理,将2018年收治的98例患者的作为研究组实施延续性护理,比较两组的护理效果。结果:研究组的治疗依从率为93.88%(92例),远高于常规组的77.68%(87例),两组数据比较存在统计学意义(P<0.05)。结论:延续性护理措施可以有效提高慢性乙型肝炎抗病毒治疗的依从性,可以在临床中推广使用。  相似文献   
9.
The hepatitis C virus (HCV) is a pandemic human pathogen posing a substantial health and economic burden in both developing and developed countries. Controlling the spread of HCV through behavioural prevention strategies has met with limited success and vaccine development remains slow. The development of antiviral therapeutic agents has also been challenging, primarily due to the lack of efficient cell culture and animal models for all HCV genotypes, as well as the large genetic diversity between HCV strains. On the other hand, the use of interferon-α-based treatments in combination with the guanosine analogue, ribavirin, achieved limited success, and widespread use of these therapies has been hampered by prevalent side effects. For more than a decade, the HCV RNA-dependent RNA polymerase (RdRp) has been targeted for antiviral development. Direct acting antivirals (DAA) have been identified which bind to one of at least six RdRp inhibitor-binding sites, and are now becoming a mainstay of highly effective and well tolerated antiviral treatment for HCV infection. Here we review the different classes of RdRp inhibitors and their mode of action against HCV. Furthermore, the mechanism of antiviral resistance to each class is described, including naturally occurring resistance-associated variants (RAVs) in different viral strains and genotypes. Finally, we review the impact of these RAVs on treatment outcomes with the newly developed regimens.  相似文献   
10.
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