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   69252篇
  免费   5587篇
  国内免费   2144篇
耳鼻咽喉   686篇
儿科学   1076篇
妇产科学   798篇
基础医学   14710篇
口腔科学   1173篇
临床医学   4279篇
内科学   9973篇
皮肤病学   1562篇
神经病学   4612篇
特种医学   1082篇
外国民族医学   20篇
外科学   4880篇
综合类   8922篇
预防医学   2708篇
眼科学   759篇
药学   11082篇
  7篇
中国医学   3380篇
肿瘤学   5274篇
  2024年   63篇
  2023年   1222篇
  2022年   1543篇
  2021年   2362篇
  2020年   2442篇
  2019年   2540篇
  2018年   2546篇
  2017年   2707篇
  2016年   2323篇
  2015年   2650篇
  2014年   4115篇
  2013年   4981篇
  2012年   4282篇
  2011年   5122篇
  2010年   4006篇
  2009年   4030篇
  2008年   3717篇
  2007年   3355篇
  2006年   3011篇
  2005年   2443篇
  2004年   2276篇
  2003年   1920篇
  2002年   1449篇
  2001年   1109篇
  2000年   1113篇
  1999年   886篇
  1998年   766篇
  1997年   768篇
  1996年   682篇
  1995年   763篇
  1994年   674篇
  1993年   552篇
  1992年   464篇
  1991年   401篇
  1990年   335篇
  1989年   276篇
  1988年   200篇
  1987年   193篇
  1986年   196篇
  1985年   377篇
  1984年   427篇
  1983年   252篇
  1982年   289篇
  1981年   229篇
  1980年   201篇
  1979年   157篇
  1978年   113篇
  1977年   111篇
  1976年   127篇
  1975年   86篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
1.
In this paper, we argue that understanding and addressing the problem of poor-quality medical products requires a more interdisciplinary approach than has been evident to date. While prospective studies based on rigorous standardized methodologies are the gold standard for measuring the prevalence of poor-quality medical products and understanding their distribution nationally and internationally, they should be complemented by social science research to unpack the complex set of social, economic, and governance factors that underlie these patterns. In the following sections, we discuss specific examples of prospective quality surveys and of social science studies, highlighting the value of cross-sector partnerships in driving high-quality, policy-relevant research in this area.  相似文献   
2.
目的比较飞秒激光制瓣准分子激光原位角膜磨镶术(FS-LASIK)、全飞秒激光小切口角膜基质透镜取出术(SMILE)和有晶状体眼后房型人工晶状体(ICL V4c)植入术三者矫正中低度近视的效果。方法采用回顾性研究。以惠州爱尔眼科医院2019年6月至2020年4月矫正中低度近视120例(120眼)作为研究对象,受术者分为FS-LASIK组、SMILE组及ICL组,每组40例(40眼),各组分别接受相应的手术,术后随访3个月比较其矫正效果。结果术后1个月及3个月,3组间视力及有效性指数对比差异无统计学意义(P>0.05);ICL组安全性指数高于SMILE组及FS-LASIK组(P<0.05)。术后3个月FS-LASIK组的三叶草像差、彗差和球差出现明显变化,而SMILE组的变化较小,ICL组变化最小(P<0.05)。结论对中低度近视FS-LASK、SMILE及ICL植入术三者均有确切疗效,而ICL V4c植入术的安全性最高,患者的视觉质量最好。  相似文献   
3.
4.
胶质淋巴系统是一个主要由星形胶质细胞水通道蛋白4介导的依靠动脉、静脉周围血管间隙的脑脊液-脑组织液交换流动的系统,是阿尔茨海默病、脑卒中、帕金森病、失眠、抑郁症等脑病的共同特征,是一条新的脑代谢途径,可以清除包括β-淀粉样蛋白、乳酸在内的代谢产物。本文综合分析了全球有关胶质淋巴系统在脑部疾病的研究,得出:胶质淋巴系统可能为神经退行性疾病等发病机制和诊治策略研究带来新视角;胶质淋巴系统有望为一些脑部疾病诊断提供新的有效证据;胶质淋巴系统可能是脑部疾病治疗给药方式的新途径。  相似文献   
5.
目的:分析SAA、hs-CRP、IL-6联合检测在儿童感染性疾病中的诊断价值。方法:选择2019年1月~2020年10月某院收治的72例感染性疾病患儿开展研究,根据患儿的病原体检测结果划分为病毒感染组和细菌感染组各36例,另选择同期体检的36名健康儿童作为研究的参照组,分别比较3组的SAA、hs-CRP、IL-6等指标水平的差异。结果:细菌感染组的SAA、hs-CRP、IL-6等指标水平及阳性率均高于病毒感染组、参照组,同时病毒感染组的SAA、hs-CRP、IL-6等指标水平及阳性率高于参照组(P<0.05);SAA、hs-CRP、IL-6联合诊断的敏感度、准确度、阳性预测值、阴性预测值均高于SAA、hs-CRP、IL-6三个指标单独检测的敏感度、准确度、阳性预测值、阴性预测值,差异有统计学意义(P<0.05);联合检测的特异度与单独检测特异度对比无统计学意义(P>0.05)。结论:SAA、hs-CRP、IL-6联合诊断在儿童感染性疾病中具备较高的诊断价值,临床可将SAA、hs-CRP、IL-6作为该病的诊断辅助指标,有效提高疾病的诊断准确性。  相似文献   
6.
7.
《Digestive and liver disease》2022,54(11):1486-1493
BackgroundCold snare polypectomy (CSP) is a promising technique for the removal of sessile serrated polyps (SSPs) ≥ 10 mm. However, the efficacy and safety of this technique remain undetermined.AimsWe aimed to comprehensively evaluate the efficacy and safety of CSP for SSPs ≥ 10 mm.MethodsPubMed, EMBASE, Web of Science and Cochrane Library were searched up to January 2021.ResultsA total of 10 studies consisting of 1727 SSPs (range, 10–40 mm) from 1021 patients were included. The overall rates of technical success, adverse events (AEs) and residual SSPs were 100%, 0.7% and 2.9%, respectively. Subgroup analysis showed that the rates of technical success and AEs were comparable between CSP and cold endoscopic mucosal resection (EMR) (99.9% vs. 100% and 1.3% vs. 0.5%, respectively), between the proximal and distal colon (100% vs. 99.9% and 0.3% vs. 0, respectively), and between polyps of 10–19 mm and ≥20 mm (99.8% vs. 100% and 0.9% vs. 0, respectively). However, subgroup analysis showed that the rate of residual SSPs was slightly lower in CSP compared with cold EMR (1.3% vs. 3.9%), as well as in polyps of 10–19 mm compared with those ≥20 mm (3.1% vs. 4.7%).ConclusionCSP was an effective and safe technique for removing SSPs ≥ 10 mm.  相似文献   
8.
《Cancer cell》2022,40(3):318-334.e9
  1. Download : Download high-res image (268KB)
  2. Download : Download full-size image
  相似文献   
9.
The Dutch Drug Rediscovery Protocol (DRUP) and the Australian Cancer Molecular Screening and Therapeutic (MoST) Program are similar nonrandomized, multidrug, pan-cancer trial platforms that aim to identify signals of clinical activity of molecularly matched targeted therapies or immunotherapies outside their approved indications. Here, we report results for advanced or metastatic cancer patients with tumors harboring cyclin D-CDK4/6 pathway alterations treated with CDK4/6 inhibitors palbociclib or ribociclib. We included adult patients that had therapy-refractory solid malignancies with the following alterations: amplifications of CDK4, CDK6, CCND1, CCND2 or CCND3, or complete loss of CDKN2A or SMARCA4. Within MoST, all patients were treated with palbociclib, whereas in DRUP, palbociclib and ribociclib were assigned to different cohorts (defined by tumor type and alteration). The primary endpoint for this combined analysis was clinical benefit, defined as confirmed objective response or stable disease ≥16 weeks. We treated 139 patients with a broad variety of tumor types; 116 with palbociclib and 23 with ribociclib. In 112 evaluable patients, the objective response rate was 0% and clinical benefit rate at 16 weeks was 15%. Median progression-free survival was 4 months (95% CI: 3-5 months), and median overall survival 5 months (95% CI: 4-6 months). In conclusion, only limited clinical activity of palbociclib and ribociclib monotherapy in patients with pretreated cancers harboring cyclin D-CDK4/6 pathway alterations was observed. Our findings indicate that monotherapy use of palbociclib or ribociclib is not recommended and that merging data of two similar precision oncology trials is feasible.  相似文献   
10.
Defects of the cystic fibrosis (CF) transmembrane conductance regulator (CFTR) protein affect the homeostasis of chloride, bicarbonate, sodium, and water in the airway surface liquid, influencing the mucus composition and viscosity, which induces a severe condition of infection and inflammation along the whole life of CF patients. The introduction of CFTR modulators, novel drugs directly intervening to rescue the function of CFTR protein, opens a new era of experimental research. The review summarizes the most recent advancements to understand the characteristics of the infective and inflammatory pathology of CF lungs.  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