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   28300篇
  免费   1991篇
  国内免费   808篇
耳鼻咽喉   592篇
儿科学   550篇
妇产科学   345篇
基础医学   3421篇
口腔科学   819篇
临床医学   4112篇
内科学   3528篇
皮肤病学   169篇
神经病学   2232篇
特种医学   850篇
外国民族医学   1篇
外科学   4650篇
综合类   3386篇
预防医学   2261篇
眼科学   300篇
药学   1953篇
  31篇
中国医学   898篇
肿瘤学   1001篇
  2024年   66篇
  2023年   631篇
  2022年   1246篇
  2021年   1542篇
  2020年   1476篇
  2019年   1266篇
  2018年   1169篇
  2017年   1161篇
  2016年   1122篇
  2015年   1033篇
  2014年   2147篇
  2013年   2128篇
  2012年   1562篇
  2011年   1745篇
  2010年   1382篇
  2009年   1429篇
  2008年   1212篇
  2007年   1202篇
  2006年   1077篇
  2005年   932篇
  2004年   834篇
  2003年   674篇
  2002年   556篇
  2001年   473篇
  2000年   384篇
  1999年   310篇
  1998年   298篇
  1997年   288篇
  1996年   250篇
  1995年   197篇
  1994年   168篇
  1993年   143篇
  1992年   152篇
  1991年   118篇
  1990年   100篇
  1989年   86篇
  1988年   84篇
  1987年   64篇
  1986年   55篇
  1985年   71篇
  1984年   67篇
  1983年   30篇
  1982年   40篇
  1981年   33篇
  1980年   28篇
  1979年   18篇
  1978年   21篇
  1977年   8篇
  1975年   6篇
  1974年   4篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
1.
The purpose of this study was to investigate the association between habitual snoring (HS), middle ear disease (MED), and speech problems in children with cleft palate. This cross-sectional study included children aged 2.0–7.9 years with non-syndromic cleft palate anomalies. Parents completed the Pediatric Sleep Questionnaire and a questionnaire about MED. Audiograms and speech assessment were also conducted. Ninety-five children were enrolled; 15.2% of families reported HS, 97.6% MED, and 17.1% speech problems. HS (37.5% vs 10.3%, P = 0.007) and early episodes of MED (92.3% vs 58.2%, P = 0.021) were more likely to be reported for children with isolated cleft palate when compared to those with cleft lip and palate. Children with cleft lip and palate had a higher frequency of MED with effusion compared to those with Robin sequence (86.4% vs 57.1%, P = 0.049). The odds ratio for HS in children with ≥1 episode of MED in the last year was 7.37 (95% confidence interval 1.55–35.15, P = 0.012). There was a trend for children with speech problems reported by parents to have HS (30.8% vs 11.5%, P= 0.076). Anatomical factors play a role in the frequency of upper airway symptoms in children with cleft palate. A recent history of at least one episode of MED was associated with an increased frequency of HS.  相似文献   
2.
This meta-analysis was designed to assess the effectiveness and safety of extracorporeal shock wave therapy (ESWT) for patients with low back pain (LBP). Pubmed, Embase, Cochrane's library, PEDro (Physiotherapy Evidence Database), China National Knowledge Infrastructure (CNKI), and Wanfang Data were searched until December 2019 to identify studies assessing the effectiveness and safety of EPSW for LBP. The prime outcome is pain intensity measured by Visual Analog Scale (VAS) or numeric rating scale (NRS). Other outcomes included functional status, quality of life, psychological outcomes measured by Oswestry Disability Index (ODI), as well as the adverse events. Mean differences (MD) were calculated for continuous outcomes, while odd ratios (OR) were calculated for binary outcomes. Revman 5.3 software was used for statistical analysis. Five randomized controlled trials (RCTs) were finally included in this meta-analysis. The pooled mean difference in post-treatment pain scores was −2.37 (P <0.0001), indicating that post-treatment pain scores was significantly higher by 2.37 in control group than in ESWT group. At a mean follow-up time of 4–6 weeks, the pooled mean difference in ODI scores was −14.10 (P <0.00001), indicating that the pooled mean difference of post-treatment ODI scores was 14.10 higher in control group than in ESWT group. The use of ESWT is effective in alleviating pain and improving the general functional state for patients with LBP. However, more evidence was needed to verify its safety.  相似文献   
3.
4.
5.
《Survey of ophthalmology》2023,68(2):257-264
RationaleObstructive sleep apnoea (OSA) has been linked to various ocular disorders, including floppy eyelid syndrome (FES). Previous studies have hypothesised the underlying association between the 2 , but results are currently still inconclusive.ObjectiveTo investigate the association between OSA and FES.MethodsFour databases (Pubmed, Embase, Scopus, and Cochrane Library) were searched from inception until 28 February 2022 for observational studies and randomized controlled trials assessing the association between OSA and FES. Two reviewers selected studies, extracted data, graded the risk of bias using the Newcastle-Ottawa scale and the quality of assessment using the Grading of Recommendations Assessment, Development, and Evaluation system. Random-effects models were used to metaanalyze the associations.ResultsTwelve studies were included in the systematic review, of which nine were suitable for metaanalysis, with a combined cohort of 1,109 patients. Risk of bias was low to moderate. The overall analysis showed a significant positive association between OSA and FES (OR = 1.89, 95% CI = 1.27–2.83, I 2 = 44%). Further analysis revealed that the more severe the OSA was, the higher the risk of developing FES. Patients with severe OSA had the nominally highest risk of developing FES (OR = 3.06, 95% CI = 1.62–5.78, I 2 = 0%), followed by moderate OSA (OR = 2.53, 95% CI = 1.29–4.97, I 2 = 0%), and patients with mild OSA had the lowest risk (OR = 1.76, 95% CI = 0.85–3.62, I 2 = 0%).ConclusionOur metaanalysis reports a positive association between OSA and FES, with increasing severity of OSA correlating with a significantly higher risk of FES. More longitudinal studies with sufficient duration of follow-up are needed to better characterise the relationship between OSA and FES.  相似文献   
6.
7.
PurposeUnderstanding the value of genetic screening and testing for monogenic disorders requires high-quality, methodologically robust economic evaluations. This systematic review sought to assess the methodological quality among such studies and examined opportunities for improvement.MethodsWe searched PubMed, Cochrane, Embase, and Web of Science for economic evaluations of genetic screening/testing (2013-2019). Methodological rigor and adherence to best practices were systematically assessed using the British Medical Journal checklist.ResultsAcross the 47 identified studies, there were substantial variations in modeling approaches, reporting detail, and sophistication. Models ranged from simple decision trees to individual-level microsimulations that compared between 2 and >20 alternative interventions. Many studies failed to report sufficient detail to enable replication or did not justify modeling assumptions, especially for costing methods and utility values. Meta-analyses, systematic reviews, or calibration were rarely used to derive parameter estimates. Nearly all studies conducted some sensitivity analysis, and more sophisticated studies implemented probabilistic sensitivity/uncertainty analysis, threshold analysis, and value of information analysis.ConclusionWe describe a heterogeneous body of work and present recommendations and exemplar studies across the methodological domains of (1) perspective, scope, and parameter selection; (2) use of uncertainty/sensitivity analyses; and (3) reporting transparency for improvement in the economic evaluation of genetic screening/testing.  相似文献   
8.
9.
PurposeThe purpose of this study was to make a systematic review and meta-analysis to determine the stent diameter (8 mm vs. 10 mm) that conveys better safety and clinical efficacy for transjugular intrahepatic portosystemic shunt (TIPS).Materials and methodsFour databases were used to identify clinical trials published from inception until March 2020. Data were extracted to estimate and compare one-year and three-year overall survivals, hepatic encephalopathy, variceal rebleeding, and shunt dysfunction rates between patients with 8 mm covered stents and those with 10 mm covered stents.ResultsFive eligible studies were selected, which included 489 patients (316 men, 173 women). The 8 mm covered stent group had higher efficacy regarding one-year or three-year overall survival (odds ratio [OR], 2.88; P = 0.003) and (OR, 1.81; P = 0.04) and lower hepatic encephalopathy (OR, 0.69; P = 0.04) compared with 10 mm covered stent group. There were no significant differences in variceal rebleeding rate (OR 0.80; P = 0.67). However, shunt dysfunction was lower in 10 mm covered stent group (OR, 2.26; P = 0.003).ConclusionsOur results suggest that the use of 8 mm covered stents should be preferred to that of 10 mm covered stents for TIPS placement when portal pressure is frequently monitored.  相似文献   
10.
《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   
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