全文获取类型
收费全文 | 12409篇 |
免费 | 745篇 |
国内免费 | 42篇 |
专业分类
耳鼻咽喉 | 117篇 |
儿科学 | 346篇 |
妇产科学 | 250篇 |
基础医学 | 1650篇 |
口腔科学 | 312篇 |
临床医学 | 1075篇 |
内科学 | 3128篇 |
皮肤病学 | 140篇 |
神经病学 | 1172篇 |
特种医学 | 355篇 |
外国民族医学 | 1篇 |
外科学 | 1730篇 |
综合类 | 117篇 |
一般理论 | 3篇 |
预防医学 | 960篇 |
眼科学 | 223篇 |
药学 | 640篇 |
中国医学 | 33篇 |
肿瘤学 | 944篇 |
出版年
2023年 | 119篇 |
2022年 | 245篇 |
2021年 | 498篇 |
2020年 | 264篇 |
2019年 | 383篇 |
2018年 | 439篇 |
2017年 | 310篇 |
2016年 | 295篇 |
2015年 | 334篇 |
2014年 | 483篇 |
2013年 | 645篇 |
2012年 | 1016篇 |
2011年 | 950篇 |
2010年 | 597篇 |
2009年 | 444篇 |
2008年 | 742篇 |
2007年 | 762篇 |
2006年 | 640篇 |
2005年 | 679篇 |
2004年 | 606篇 |
2003年 | 486篇 |
2002年 | 513篇 |
2001年 | 153篇 |
2000年 | 108篇 |
1999年 | 127篇 |
1998年 | 82篇 |
1997年 | 74篇 |
1996年 | 69篇 |
1995年 | 72篇 |
1994年 | 58篇 |
1993年 | 43篇 |
1992年 | 65篇 |
1991年 | 46篇 |
1990年 | 62篇 |
1989年 | 41篇 |
1988年 | 48篇 |
1987年 | 38篇 |
1986年 | 58篇 |
1985年 | 40篇 |
1984年 | 38篇 |
1983年 | 52篇 |
1982年 | 37篇 |
1981年 | 30篇 |
1980年 | 30篇 |
1979年 | 29篇 |
1977年 | 25篇 |
1976年 | 22篇 |
1975年 | 21篇 |
1974年 | 29篇 |
1972年 | 20篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
171.
172.
Heng Seh Gabriel Tan Kian Chong Lim Jeen Nee Lui Wei Ming Clement Lai Victoria Soo Hoon Yu 《Journal of endodontics》2021,47(2):169-177
IntroductionThe incidence of immediate postobturation pain associated with 2 sealer techniques was compared and potential prognostic factors identified.MethodsPatients referred for endodontic treatment were recruited with informed consent. Root canals were debrided and teeth rendered asymptomatic before random allocation to receive TotalFill BC (FKG Dentaire SA, La Chaux-de-Fonds, Switzerland) or AH Plus sealer (Dentsply Maillefer, Ballaigues, Switzerland). Patients blinded to the sealer reported their postobturation pain experience 1, 3, and 7 days after treatment. Blinded and calibrated assessors independently reviewed treatment quality, sealer extrusion, and radiographic data under standardized conditions.ResultsOne hundred sixty eligible patients (163 teeth, 95.3%) returned their pain diary. No postobturation pain difference was found between the 2 sealers (P > .05), although the AH Plus sealer technique was significantly associated with extrusion beyond the apex (P < .05; odds ratio [OR] = 3.02; 95% confidence interval [CI], 1.39–6.57). Thirty-three (20.6%) patients reported pain on day 1 (median 1 = very mild pain), 16 (10.0%) on day 3 (median 1 = very mild pain), and 9 (5.6%) on day 7 (median 2 = mild pain). The prognostic factors were as follows:(1) moderate/severe preoperative pain (OR = 4.41; 95% CI, 1.42–13.76 on day 3 and OR = 5.16; 95% CI, 1.17–22.78 on day 7),(2) provoked preoperative pain (OR = 4.24; 95% CI, 1.40–12.78 on day 3 and OR = 5.35; 95% CI, 1.27–22.51 on day 7),(3) pulpless tooth (OR = 0.11; 95% CI, 0.02–0.57 on day 3), and(4) sonic activation during treatment (OR = 3.02; 95% CI, 1.39–6.57 on day 1 and OR = 3.01; 95% CI, 1.05–8.59 on day 3).ConclusionsThere was no significant difference in pain experience between teeth filled using AH Plus or TotalFill BC Sealer 1, 3, and 7 days after obturation. Patient- and treatment-related factors could influence postobturation pain. 相似文献
173.
174.
175.
Tom C. Nguyen Matthew D. Terwelp Elizabeth H. Stephens David D. Odell Gabriel Loor Damien J. LaPar Walter F. DeNino Benjamin Wei Muhammad Aftab Ryan A. Macke Jennifer S. Nelson Kathleen S. Berfield John F. Lazar William Stein Samuel J. Youssef Vakhtang Tchantchaleishvili 《The Annals of thoracic surgery》2015,99(6):2070-2076
176.
177.
Moria J. Smoski Shian-Ling Keng Jie Lisa Ji Tyler Moore Jared Minkel Gabriel S. Dichter 《Social cognitive and affective neuroscience》2015,10(9):1187-1194
Mood disorders are characterized by impaired emotion regulation abilities, reflected in alterations in frontolimbic brain functioning during regulation. However, little is known about differences in brain function when comparing regulatory strategies. Reappraisal and emotional acceptance are effective in downregulating negative affect, and are components of effective depression psychotherapies. Investigating neural mechanisms of reappraisal vs emotional acceptance in remitted major depressive disorder (rMDD) may yield novel mechanistic insights into depression risk and prevention. Thirty-seven individuals (18 rMDD, 19 controls) were assessed during a functional magnetic resonance imaging task requiring reappraisal, emotional acceptance or no explicit regulation while viewing sad images. Lower negative affect was reported following reappraisal than acceptance, and was lower following acceptance than no explicit regulation. In controls, the acceptance > reappraisal contrast revealed greater activation in left insular cortex and right prefrontal gyrus, and less activation in several other prefrontal regions. Compared with controls, the rMDD group had greater paracingulate and right midfrontal gyrus (BA 8) activation during reappraisal relative to acceptance. Compared with reappraisal, acceptance is associated with activation in regions linked to somatic and emotion awareness, although this activation is associated with less reduction in negative affect. Additionally, a history of MDD moderated these effects. 相似文献
178.
179.
Milena Dropa Barbara Ghiglione Maria Helena Matté Livia Carminato Balsalobre Nilton Lincopan Glavur Rogério Matté Gabriel Gutkind Pablo Power 《Antimicrobial agents and chemotherapy》2015,59(3):1815-1817
CTX-M-131 is a natural Asp240Gly variant from the CTX-M-2 group detected in a Providencia rettgeri clinical strain from Brazil. Molecular analysis showed that blaCTX-M-131 was inserted in a complex class 1 integron harbored by a 112-kb plasmid, which has not been previously described as a platform for CTX-M-encoding genes with the Asp240Gly mutation. Steady-state kinetic parameters showed that the enzyme has a typical cefotaximase catalytic profile and an enhanced activity against ceftazidime. 相似文献
180.
Matthew E. Wand Kate S. Baker Gabriel Benthall Hannah McGregor James W. I. McCowen Ana Deheer-Graham J. Mark Sutton 《Antimicrobial agents and chemotherapy》2015,59(7):3966-3972
The EGD Murray collection consists of approximately 500 clinical bacterial isolates, mainly Enterobacteriaceae, isolated from around the world between 1917 and 1949. A number of these “Murray” isolates have subsequently been identified as Klebsiella pneumoniae. Antimicrobial susceptibility testing of these isolates showed that over 30% were resistant to penicillins due to the presence of diverse blaSHV β-lactamase genes. Analysis of susceptibility to skin antiseptics and triclosan showed that while the Murray isolates displayed a range of MIC/minimal bactericidal concentration (MBC) values, the mean MIC value was lower than that for more modern K. pneumoniae isolates tested. All Murray isolates contained the cation efflux gene cepA, which is involved in disinfectant resistance, but those that were more susceptible to chlorhexidine were found to have a 9- or 18-bp insertion in this gene. Susceptibility to other disinfectants, e.g., H2O2, in the Murray isolates was comparable to that in modern K. pneumoniae isolates. The Murray isolates were also less virulent in Galleria and had a different complement of putative virulence factors than the modern isolates, with the exception of an isolate related to the modern lineage CC23. More of the modern isolates (41% compared to 8%) are classified as good/very good biofilm formers, but there was overlap in the two populations. This study demonstrated that a significant proportion of the Murray Klebsiella isolates were resistant to penicillins before their routine use. This collection of pre-antibiotic era isolates may provide significant insights into adaptation in K. pneumoniae in relation to biocide susceptibility. 相似文献