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   196259篇
  免费   52405篇
  国内免费   468篇
耳鼻咽喉   2868篇
儿科学   7343篇
妇产科学   2785篇
基础医学   30881篇
口腔科学   7254篇
临床医学   25732篇
内科学   46503篇
皮肤病学   8941篇
神经病学   25787篇
特种医学   6778篇
外国民族医学   3篇
外科学   33641篇
综合类   1766篇
一般理论   156篇
预防医学   15011篇
眼科学   3805篇
药学   13527篇
中国医学   1123篇
肿瘤学   15228篇
  2023年   595篇
  2022年   915篇
  2021年   3620篇
  2020年   6415篇
  2019年   12981篇
  2018年   12805篇
  2017年   13301篇
  2016年   14106篇
  2015年   14277篇
  2014年   15501篇
  2013年   17568篇
  2012年   12639篇
  2011年   12938篇
  2010年   13885篇
  2009年   9845篇
  2008年   10134篇
  2007年   9285篇
  2006年   9039篇
  2005年   8477篇
  2004年   8346篇
  2003年   7639篇
  2002年   7269篇
  2001年   2483篇
  2000年   2167篇
  1999年   1891篇
  1998年   1562篇
  1997年   1209篇
  1996年   1058篇
  1995年   963篇
  1994年   846篇
  1993年   862篇
  1992年   1106篇
  1991年   1047篇
  1990年   935篇
  1989年   911篇
  1988年   852篇
  1987年   874篇
  1986年   778篇
  1985年   822篇
  1984年   704篇
  1983年   604篇
  1982年   575篇
  1981年   488篇
  1980年   426篇
  1979年   465篇
  1978年   338篇
  1977年   315篇
  1976年   306篇
  1974年   302篇
  1973年   307篇
排序方式: 共有10000条查询结果,搜索用时 31 毫秒
1.
2.
3.
4.
ObjectiveSpinal cord stimulation (SCS) is an effective treatment in failed back surgery syndrome (FBSS). We studied the effect of preimplantation opioid use on SCS outcome and the effect of SCS on opioid use during a two-year follow-up period.Materials and methodsThe study cohort included 211 consecutive FBSS patients who underwent an SCS trial from January 1997 to March 2014. Participants were divided into groups, which were as follows: 1) SCS trial only (n = 47), 2) successful SCS (implanted and in use throughout the two-year follow-up period, n = 131), and 3) unsuccessful SCS (implanted but later explanted or revised due to inadequate pain relief, n = 29). Patients who underwent explantation for other reasons (n = 4) were excluded. Opioid purchase data from January 1995 to March 2016 were retrieved from national registries.ResultsHigher preimplantation opioid doses associated with unsuccessful SCS (ROC: AUC = 0.66, p = 0.009), with 35 morphine milligram equivalents (MME)/day as the optimal cutoff value. All opioids were discontinued in 23% of patients with successful SCS, but in none of the patients with unsuccessful SCS (p = 0.004). Strong opioids were discontinued in 39% of patients with successful SCS, but in none of the patients with unsuccessful SCS (p = 0.04). Mean opioid dose escalated from 18 ± 4 MME/day to 36 ± 6 MME/day with successful SCS and from 22 ± 8 MME/day to 82 ± 21 MME/day with unsuccessful SCS (p < 0.001).ConclusionsHigher preimplantation opioid doses were associated with SCS failure, suggesting the need for opioid tapering before implantation. With continuous SCS therapy and no explantation or revision due to inadequate pain relief, 39% of FBSS patients discontinued strong opioids, and 23% discontinued all opioids. This indicates that SCS should be considered before detrimental dose escalation.  相似文献   
5.
6.
7.
Lesbian, gay, bisexual, transgender, queer and two-spirit plus (LGBTQ2S+) people have distinct healthcare needs that may be unaddressed in many undergraduate healthcare curricula. The Radiation Therapy Program (RADTH) at the University of Alberta underwent a review of the three-year didactic curriculum using an online survey. The survey sought to ascertain if, where and how topics related to LGBTQ2S + healthcare are taught. Results indicated that out of 10 RADTH program faculty respondents, three teach related topics. The total time dedicated within the three-year curriculum was approximately three and a half hours. Other findings showed that faculty are interested in receiving more education in this area and would favour discussions about how to incorporate these themes into appropriate courses. This preliminary investigation demonstrated that there has been some initial work in this area, but there is more to be done.  相似文献   
8.
9.
Vaccination is a vital health care initiative to prevent individual and population infection. To increase vaccination rates the federal government implemented the ‘No Jab, No Pay’ policy, where eligibility for several government benefits required children to be fully vaccinated by removing ‘conscientious objections’ and expanding the age range of children whose families receive benefits. This study assesses the impact of this policy at a local area within a single medical practice community in NSW, Australia. A retrospective clinical audit was performed between 2012 and 2017 on a single general practice's vaccination records for children ≤19 years. Catch-up vaccinations were assessed based on age at vaccination. Incidence of catch-up vaccinations was assessed for each of four years before and two years after the implementation of the ‘No Jab, No Pay’ policy in January 2016, along with the age of children and vaccination(s) given. Catch-up vaccinations were assessed temporally either side of implementation of ‘No Jab, No Pay’. Comparing the average annual vaccination catch-up incidence rate of 6.2% pre-implementation (2012–2015), there was an increase to 9.2% in 2016 (p < .001) and 7.8% in 2017 (p = .027). Secondary outcome measurement of catch-up vaccination incidence rates before (2012–2015) and after (2016–2017) ‘No Jab, No Pay’ implementation showed statistically significant increases for children aged 8–11 years (3.2%–5.6%, p = .038), 12–15 years (7.5%–14.7%, p < .001) and 16–19 years (3.3%–10.2%, p < .001) along with a statistically significant reduction in children aged 1–3 years (11.4%–6.2%, p = .015). Also, catch-up rates for DTPa significantly increased after program implementation. This study demonstrates that the Australian federal government vaccination policy ‘No Jab, No Pay’ was coincident with an increase in catch-up vaccinations within a rural NSW community served by one medical practice, especially for older children.  相似文献   
10.
Metformin, a drug for type 2 diabetes mellitus, has shown therapeutic effects for various cancers. However, it had no beneficial effects on the survival rate of human malignant mesothelioma (HMM) patients. The present study was performed to elucidate the underlying mechanism of metformin resistance in HMM cells. Glucose‐starved HMM cells had enhanced resistance to metformin, demonstrated by decreased apoptosis and autophagy and increased cell survival. These cells showed abnormalities in mitochondria, such as decreased ATP synthesis, morphological elongation, altered mitochondrial permeability transition pore and hyperpolarization of mitochondrial membrane potential (MMP). Intriguingly, Mdr1 was significantly upregulated in mitochondria but not in cell membrane. The upregulated mitochondrial Mdr1 was reversed by treatment with carbonyl cyanide m‐chlorophenyl hydrazone, an MMP depolarization inducer. Furthermore, apoptosis and autophagy were increased in multidrug resistance protein 1 knockout HMM cells cultured under glucose starvation with metformin treatment. The data suggest that mitochondrial Mdr1 plays a critical role in the chemoresistance to metformin in HMM cells, which could be a potential target for improving its therapeutic efficacy.  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