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   4879844篇
  免费   417406篇
  国内免费   16185篇
耳鼻咽喉   69830篇
儿科学   155743篇
妇产科学   130425篇
基础医学   735766篇
口腔科学   139166篇
临床医学   449128篇
内科学   890981篇
皮肤病学   117999篇
神经病学   417627篇
特种医学   192750篇
外国民族医学   1212篇
外科学   738610篇
综合类   143400篇
现状与发展   24篇
一般理论   2831篇
预防医学   410542篇
眼科学   116687篇
药学   348078篇
  19篇
中国医学   13878篇
肿瘤学   238739篇
  2021年   56987篇
  2019年   64744篇
  2018年   79467篇
  2017年   62129篇
  2016年   68958篇
  2015年   81496篇
  2014年   116344篇
  2013年   182079篇
  2012年   140316篇
  2011年   146780篇
  2010年   132817篇
  2009年   132574篇
  2008年   132241篇
  2007年   141003篇
  2006年   149010篇
  2005年   143812篇
  2004年   144051篇
  2003年   133940篇
  2002年   123751篇
  2001年   188475篇
  2000年   185975篇
  1999年   167519篇
  1998年   75679篇
  1997年   70834篇
  1996年   68732篇
  1995年   64462篇
  1994年   58383篇
  1993年   53639篇
  1992年   123712篇
  1991年   118593篇
  1990年   112994篇
  1989年   109737篇
  1988年   101712篇
  1987年   100093篇
  1986年   94555篇
  1985年   92305篇
  1984年   76060篇
  1983年   67032篇
  1982年   51318篇
  1981年   47468篇
  1980年   44517篇
  1979年   67428篇
  1978年   53121篇
  1977年   46208篇
  1976年   43134篇
  1975年   42939篇
  1974年   49161篇
  1973年   47334篇
  1972年   44534篇
  1971年   40913篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
991.

Background

The ZOE-50 (NCT01165177) and ZOE-70 (NCT01165229) phase 3 clinical trials showed that the adjuvanted recombinant zoster vaccine (RZV) was ≥90% efficacious in preventing herpes zoster in adults. Here we present a comprehensive overview of the safety data from these studies.

Methods

Adults aged ≥50 (ZOE-50) and ≥70 (ZOE-70) years were randomly vaccinated with RZV or placebo. Safety analyses were performed on the pooled total vaccinated cohort, consisting of participants receiving at least one dose of RZV or placebo. Solicited and unsolicited adverse events (AEs) were collected for 7 and 30?days after each vaccination, respectively. Serious AEs (SAEs) were collected from the first vaccination until 12?months post-last dose. Fatal AEs, vaccination-related SAEs, and potential immune-mediated diseases (pIMDs) were collected during the entire study period.

Results

Safety was evaluated in 14,645 RZV and 14,660 placebo recipients. More RZV than placebo recipients reported unsolicited AEs (50.5% versus 32.0%); the difference was driven by transient injection site and solicited systemic reactions that were generally seen in the first week post-vaccination. The occurrence of overall SAEs (RZV: 10.1%; Placebo: 10.4%), fatal AEs (RZV: 4.3%; Placebo: 4.6%), and pIMDs (RZV: 1.2%; Placebo: 1.4%) was balanced between groups. The occurrence of possible exacerbations of pIMDs was rare and similar between groups. Overall, except for the expected local and systemic symptoms, the safety results were comparable between the RZV and Placebo groups irrespective of participant age, gender, or race.

Conclusions

No safety concerns arose, supporting the favorable benefit-risk profile of RZV.  相似文献   
992.
Understanding why persons with human immunodeficiency virus (HIV) have accelerated atherosclerosis and its sequelae, including coronary artery disease (CAD) and myocardial infarction, is necessary to provide appropriate care to a large and aging population with HIV. In this review, we delineate the diverse pathophysiologies underlying HIV-associated CAD and discuss how these are implicated in the clinical manifestations of CAD among persons with HIV. Several factors contribute to HIV-associated CAD, with chronic inflammation and immune activation likely representing the primary drivers. Increased monocyte activation, inflammation, and hyperlipidemia present in chronic HIV infection also mirror the pathophysiology of plaque rupture. Furthermore, mechanisms central to plaque erosion, such as activation of toll-like receptor 2 and formation of neutrophil extracellular traps, are also abundant in HIV. In addition to inflammation and immune activation in general, persons with HIV have a higher prevalence than uninfected persons of traditional cardiovascular risk factors, including dyslipidemia, hypertension, insulin resistance, and tobacco use. Antiretroviral therapies, although clearly necessary for HIV treatment and survival, have had varied effects on CAD, but newer generation regimens have reduced cardiovascular toxicities. From a clinical standpoint, this mix of risk factors is implicated in earlier CAD among persons with HIV than uninfected persons; whether the distribution and underlying plaque content of CAD for persons with HIV differs considerably from uninfected persons has not been definitively studied. Furthermore, the role of cardiovascular risk estimators in HIV remains unclear, as does the role of traditional and emerging therapies; no trials of CAD therapies powered to detect clinical events have been completed among persons with HIV.  相似文献   
993.
994.
995.
996.
997.
Canadian Journal of Anesthesia/Journal canadien d'anesthésie -  相似文献   
998.
Developmental dyslexia affects 40–60% of children with a familial risk (FHD+) compared to a general prevalence of 5–10%. Despite the increased risk, about half of FHD+ children develop typical reading abilities (FHD+Typical). Yet the underlying neural characteristics of favorable reading outcomes in at‐risk children remain unknown. Utilizing a retrospective, longitudinal approach, this study examined whether putative protective neural mechanisms can be observed in FHD+Typical at the prereading stage. Functional and structural brain characteristics were examined in 47 FHD+ prereaders who subsequently developed typical (n = 35) or impaired (n = 12) reading abilities and 34 controls (FHD?Typical). Searchlight‐based multivariate pattern analyses identified distinct activation patterns during phonological processing between FHD+Typical and FHD?Typical in right inferior frontal gyrus (RIFG) and left temporo‐parietal cortex (LTPC) regions. Follow‐up analyses on group‐specific classification patterns demonstrated LTPC hypoactivation in FHD+Typical compared to FHD?Typical, suggesting this neural characteristic as an FHD+ phenotype. In contrast, RIFG showed hyperactivation in FHD+Typical than FHD?Typical, and its activation pattern was positively correlated with subsequent reading abilities in FHD+ but not controls (FHD?Typical). RIFG hyperactivation in FHD+Typical was further associated with increased interhemispheric functional and structural connectivity. These results suggest that some protective neural mechanisms are already established in FHD+Typical prereaders supporting their typical reading development.  相似文献   
999.
1000.
G protein-coupled estrogen receptor-1 (GPER), a member of the G protein-coupled receptor (GPCR) superfamily, mediates estrogen-induced proliferation of normal and malignant breast epithelial cells. However, its role in breast cancer stem cells (BCSCs) remains unclear. Here we showed greater expression of GPER in BCSCs than non-BCSCs of three patient-derived xenografts of ER/PR+ breast cancers. GPER silencing reduced stemness features of BCSCs as reflected by reduced mammosphere forming capacity in vitro, and tumor growth in vivo with decreased BCSC populations. Comparative phosphoproteomics revealed greater GPER-mediated PKA/BAD signaling in BCSCs. Activation of GPER by its ligands, including tamoxifen (TMX), induced phosphorylation of PKA and BAD-Ser118 to sustain BCSC characteristics. Transfection with a dominant-negative mutant BAD (Ser118Ala) led to reduced cell survival. Taken together, GPER and its downstream signaling play a key role in maintaining the stemness of BCSCs, suggesting that GPER is a potential therapeutic target for eradicating BCSCs.  相似文献   
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