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   3441085篇
  免费   281318篇
  国内免费   13330篇
耳鼻咽喉   46848篇
儿科学   109188篇
妇产科学   89436篇
基础医学   548163篇
口腔科学   92968篇
临床医学   313558篇
内科学   606977篇
皮肤病学   91244篇
神经病学   294178篇
特种医学   134127篇
外国民族医学   288篇
外科学   524597篇
综合类   102306篇
现状与发展   24篇
一般理论   2362篇
预防医学   294704篇
眼科学   78065篇
药学   235193篇
  26篇
中国医学   9353篇
肿瘤学   162128篇
  2021年   54899篇
  2020年   34998篇
  2019年   57918篇
  2018年   71181篇
  2017年   54277篇
  2016年   59709篇
  2015年   73868篇
  2014年   107967篇
  2013年   173119篇
  2012年   93996篇
  2011年   94546篇
  2010年   116920篇
  2009年   121223篇
  2008年   81718篇
  2007年   85186篇
  2006年   95064篇
  2005年   90801篇
  2004年   92377篇
  2003年   83073篇
  2002年   72949篇
  2001年   102492篇
  2000年   95143篇
  1999年   95219篇
  1998年   64562篇
  1997年   62608篇
  1996年   60760篇
  1995年   56198篇
  1994年   50452篇
  1993年   47131篇
  1992年   67551篇
  1991年   64811篇
  1990年   61435篇
  1989年   60602篇
  1988年   56438篇
  1987年   55199篇
  1986年   52629篇
  1985年   52231篇
  1984年   48154篇
  1983年   44326篇
  1982年   41714篇
  1981年   39432篇
  1980年   37167篇
  1979年   40669篇
  1978年   36257篇
  1977年   32847篇
  1976年   30137篇
  1975年   29010篇
  1974年   30505篇
  1973年   29605篇
  1972年   27858篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
61.
62.
63.
A 42‐year‐old man presented with a viral prodrome and tested positive for influenza A. He rapidly deteriorated developing cardiogenic shock, rhabdomyolysis, and acute kidney injury. Patient improved 1 week later with supportive measures including vasopressors, inotropes, and an intraaortic balloon pump. We report this case as it highlights the discordance between echocardiographic ventricular wall thickening as a result of myocardial edema, and electrocardiographic findings at presentation, with a reversal in findings at time of resolution. Additionally, there was some suggestion of a regional pattern to the reduced longitudinal strain.  相似文献   
64.
65.
66.
AimsThe aims were to 1) develop the pharmacokinetics model to describe and predict observed tanezumab concentrations over time, 2) test possible covariate parameter relationships that could influence clearance and distribution and 3) assess the impact of fixed dosing vs. a dosing regimen adjusted by body weight.MethodsIndividual concentration–time data were determined from 1608 patients in four phase 3 studies conducted to assess efficacy and safety of intravenous tanezumab. Patients received two or three intravenous doses (2.5, 5 or 10 mg) every 8 weeks. Blood samples for assessment of tanezumab PK were collected at baseline, 1 h post‐dose and at weeks 4, 8, 16 and 24 (or early termination) in all studies. Blood samples were collected at week 32 in two studies. Plasma samples were analyzed using a sensitive, specific, validated enzyme‐linked immunosorbent assay.ResultsA two compartment model with parallel linear and non‐linear elimination processes adequately described the data. Population estimates for clearance (CL), central volume (V 1), peripheral volume (V 2), inter‐compartmental clearance, maximum elimination capacity (VM) and concentration at half‐maximum elimination capacity were 0.135 l day–1, 2.71 l, 1.98 l, 0.371 l day–1, 8.03 μg day–1 and 27.7 ng ml–1, respectively. Inter‐individual variability (IIV) was included on CL, V 1, V 2 and VM. A mixture model accounted for the distribution of residual error. While gender, dose and creatinine clearance were significant covariates, only body weight as a covariate of CL, V 1 and V 2 significantly reduced IIV.ConclusionsThe small increase in variability associated with fixed dosing is consistent with other monoclonal antibodies and does not change risk : benefit.  相似文献   
67.
There is an increasing number of effective therapies for fracture prevention in adults at risk of osteoporosis. However, shortcomings in the evidence underpinning our management of osteoporosis still exist. Evidence of antifracture efficacy in the groups of patients who most commonly use calcium and vitamin D supplements is lacking, the safety of calcium supplements is in doubt, and the safety and efficacy of high doses of vitamin D give cause for concern. Alendronate, risedronate, zoledronate and denosumab have been shown to prevent spine, nonspine and hip fractures; in addition, teriparatide and strontium ranelate prevent both spine and nonspine fractures, and raloxifene and ibandronate prevent spine fractures. However, most trials provide little information regarding long‐term efficacy or safety. A particular concern at present is the possibility that oral bisphosphonates might cause atypical femoral fractures. Observational data suggest that the incidence of this type of fracture increases steeply with duration of bisphosphonate use, resulting in concern that the benefit–risk balance may become negative in the long term, particularly in patients in whom the osteoporotic fracture risk is not high. Therefore, reappraisal of ongoing use of bisphosphonates after about 5 years is endorsed by expert consensus, and ‘drug holidays’ should be considered at this time. Further studies are needed to guide clinical practice in this area.  相似文献   
68.
The value of adding simeprevir (SMV) vs placebo (PBO) to peginterferon and ribavirin (PR) for treatment of chronic hepatitis C virus infection was examined using patient‐reported outcomes (PROs); further, concordance of PROs with virology endpoints and adverse events (AEs) was explored. Patients (= 768 SMV/PR,= 393 PBO/PR) rated fatigue (FSS), depressive symptoms (CES‐D) and functional impairment (WPAI: Hepatitis C Productivity, Daily Activity and Absenteeism) at baseline and throughout treatment in three randomised, double‐blind trials comparing the addition of SMV or PBO during initial 12 weeks of PR. PR was administered for 48 weeks (PBO group) and 24/48 weeks (SMV group) using a response‐guided therapy (RGT) approach. Mean PRO scores (except Absenteeism) worsened from baseline to Week 4 to the same extent in both groups but reverted after Week 24 for SMV/PR and only after Week 48 for PBO/PR. Accordingly, there was a significantly lower area under the curve (baseline–Week 60, AUC60) and fewer weeks with clinically important worsening of scores in the SMV/PR group at any time point. Incidences of patients with fatigue and anaemia AEs were similar in both groups, but FSS scores showed that clinically important increases in fatigue lasted a mean of 6.9 weeks longer with PBO/PR (P < 0.001). PRO score subgroup analysis indicated better outcomes for patients who met the criteria for RGT or achieved sustained virological response 12 weeks post‐treatment (SVR12); differences in mean PRO scores associated with fibrosis level were only observed with PBO/PR. Greater efficacy of SMV/PR enabled reduced treatment duration and reduced time with PR‐related AEs without adding to AE severity.  相似文献   
69.
70.
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