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   15905篇
  免费   936篇
  国内免费   52篇
耳鼻咽喉   206篇
儿科学   482篇
妇产科学   374篇
基础医学   2519篇
口腔科学   639篇
临床医学   1477篇
内科学   2602篇
皮肤病学   731篇
神经病学   1754篇
特种医学   700篇
外科学   2386篇
综合类   153篇
一般理论   16篇
预防医学   919篇
眼科学   234篇
药学   814篇
中国医学   9篇
肿瘤学   878篇
  2022年   133篇
  2021年   332篇
  2020年   205篇
  2019年   256篇
  2018年   317篇
  2017年   236篇
  2016年   290篇
  2015年   301篇
  2014年   437篇
  2013年   557篇
  2012年   834篇
  2011年   787篇
  2010年   463篇
  2009年   401篇
  2008年   699篇
  2007年   740篇
  2006年   648篇
  2005年   689篇
  2004年   631篇
  2003年   618篇
  2002年   631篇
  2001年   318篇
  2000年   264篇
  1999年   274篇
  1998年   174篇
  1997年   141篇
  1996年   134篇
  1995年   101篇
  1994年   106篇
  1993年   109篇
  1992年   165篇
  1991年   127篇
  1990年   140篇
  1989年   141篇
  1988年   141篇
  1987年   162篇
  1986年   131篇
  1985年   139篇
  1984年   113篇
  1983年   103篇
  1982年   109篇
  1981年   84篇
  1980年   92篇
  1978年   88篇
  1976年   90篇
  1933年   93篇
  1932年   88篇
  1931年   93篇
  1930年   91篇
  1913年   83篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
1.
Fibroblast growth factor receptors (FGFRs) are aberrantly activated through single-nucleotide variants, gene fusions and copy number amplifications in 5–10% of all human cancers, although this frequency increases to 10–30% in urothelial carcinoma and intrahepatic cholangiocarcinoma. We begin this review by highlighting the diversity of FGFR genomic alterations identified in human cancers and the current challenges associated with the development of clinical-grade molecular diagnostic tests to accurately detect these alterations in the tissue and blood of patients. The past decade has seen significant advancements in the development of FGFR-targeted therapies, which include selective, non-selective and covalent small-molecule inhibitors, as well as monoclonal antibodies against the receptors. We describe the expanding landscape of anti-FGFR therapies that are being assessed in early phase and randomised controlled clinical trials, such as erdafitinib and pemigatinib, which are approved by the Food and Drug Administration for the treatment of FGFR3-mutated urothelial carcinoma and FGFR2-fusion cholangiocarcinoma, respectively. However, despite initial sensitivity to FGFR inhibition, acquired drug resistance leading to cancer progression develops in most patients. This phenomenon underscores the need to clearly delineate tumour-intrinsic and tumour-extrinsic mechanisms of resistance to facilitate the development of second-generation FGFR inhibitors and novel treatment strategies beyond progression on targeted therapy.Subject terms: Cancer, Cancer  相似文献   
2.

Objective

To examine whether a healthy weight intervention embedded in the Parents as Teachers (PAT) home visiting program, which was previously found to improve mothers’ body mass index (BMI) and obesity-related behaviors, changed the BMI of preschool children or maternal feeding practices.

Methods

This stratified randomized trial included preschool-aged children at risk for overweight whose mothers were overweight or had obesity (n?=?179). The Healthy Eating and Active Living Taught at Home (HEALTH) intervention was based on the Diabetes Prevention Program. Differences were examined using repeated-measures mixed-ANOVA models.

Results

Compared with PAT usual care, the HEALTH intervention had no effect on children's BMI or maternal feeding practices. However, combined analyses showed that children's BMI percentile decreased (P??=?.007), BMI z-scores were maintained (P??=?.19), and 3 of 8 feeding practices improved over time (P < .05).

Conclusions and Implications

Additional research is needed to assess the effectiveness of PAT to prevent preschool-age obesity using rigorous designs (eg, group-randomized trials) and to identify its active components. HEALTH is ready to be scaled up to prevent maternal weight gain through embedding within the national PAT program.  相似文献   
3.
Clinical Epileptology - Der plötzliche unerwartete Tod stellt eine seltene, aber schwerwiegende Komplikation für Epilepsiepatienten dar. Das Risiko hierfür ist u. a. nachts und...  相似文献   
4.

Background

The efficacy of dexamethasone in extending the duration of local anaesthetic block is uncertain. In a randomised controlled triple blind crossover study in volunteers, we tested the hypothesis that neither i.v. nor perineurally administered dexamethasone prolongs the sensory block achieved with ropivacaine.

Methods

Ultrasound-guided ulnar nerve blocks (ropivacaine 0.75% wt/vol, 3 ml, with saline 1 ml with or without dexamethasone 4 mg) were performed on three occasions in 24 male volunteers along with an i.v. injection of saline 1 ml with or without dexamethasone 4 mg. The combinations of saline and dexamethasone were as follows: control group, perineural and i.v. saline; perineural group, perineural dexamethasone and i.v. saline; i.v. group, perineural saline and i.v. dexamethasone. Sensory block was measured using a VAS in response to pinprick testing. The duration of sensory block was the primary outcome and time to onset of sensory block the secondary outcome.

Results

All 24 subjects completed the trial. The median [inter-quartile range (IQR)] duration of sensory block was 6.87 (5.85–7.62) h in the control group, 7.37 (5.78–7.93) h in the perineural group and 7.37 (6.10–7.97) h in the i.v. group (P=0.61). There was also no significant difference in block onset time between the three groups.

Conclusion

Dexamethasone 4 mg has no clinically relevant effect on the duration of sensory block provided by ropivacaine applied to the ulnar nerve.

Clinical trial registration

DRKS, 00014604; EudraCT, 2018-001221-98.  相似文献   
5.
6.
BACKGROUND: An augmented reality tool for computer assisted surgery named X-Scope allows visual tracking of real anatomical structures in superposition with volume rendered CT or MRI scans and thus can be used for navigated translocation of bony segments. METHODS: In a feasibility study X-Scope was used in orthognathic surgery to control the translocation of the maxilla after Le Fort I osteotomy within a bimaxillary procedure. The situation achieved was compared with the pre-operative situation by means of cephalometric analysis on lateral and frontal cephalograms. RESULTS: The technique was successfully utilized in 5 patients. Maxillary positioning using X-Scope was accomplished accurately within a range of 1mm. The tool was used in all cases in addition to the usual intra-operative splints. A stand-alone application without conventional control does not yet seem reasonable. CONCLUSION: Augmented reality tools like X-Scope may be helpful for controlling maxillary translocation in orthognathic surgery. The application to other interventions in cranio-maxillofacial surgery such as Le Fort III osteotomy, fronto-orbital advancement, and cranial vault reshaping or repair may also be considered.  相似文献   
7.
8.
A patient with long-standing Tourette's syndrome had a dramatic exacerbation of symptoms following the rapid withdrawal of haloperidol. Clonidine administration resulted in a disappearance of tics, which recurred 6 days later. The role of clonidine in blocking withdrawal-induced symptoms in patients with Tourette's syndrome treated with long-term neuroleptics is discussed from a clinical and neurobiological perspective. The implications of this case for the treatment of supersensitivity psychosis and tricyclic withdrawal states with clonidine are also discussed.  相似文献   
9.
10.
International Journal of Legal Medicine -  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