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   1277884篇
  免费   94639篇
  国内免费   1985篇
耳鼻咽喉   18187篇
儿科学   42402篇
妇产科学   37915篇
基础医学   187285篇
口腔科学   35402篇
临床医学   108473篇
内科学   251520篇
皮肤病学   26517篇
神经病学   99543篇
特种医学   50253篇
外国民族医学   366篇
外科学   198348篇
综合类   26662篇
现状与发展   1篇
一般理论   306篇
预防医学   92859篇
眼科学   29027篇
药学   98009篇
  1篇
中国医学   2500篇
肿瘤学   68932篇
  2018年   11931篇
  2015年   11707篇
  2014年   16104篇
  2013年   24590篇
  2012年   33835篇
  2011年   36256篇
  2010年   21390篇
  2009年   20153篇
  2008年   35223篇
  2007年   38215篇
  2006年   38789篇
  2005年   38039篇
  2004年   36657篇
  2003年   35628篇
  2002年   35159篇
  2001年   58288篇
  2000年   59765篇
  1999年   50847篇
  1998年   14307篇
  1997年   12882篇
  1996年   13134篇
  1995年   12388篇
  1994年   11750篇
  1993年   10862篇
  1992年   41063篇
  1991年   40490篇
  1990年   39989篇
  1989年   38803篇
  1988年   36171篇
  1987年   35426篇
  1986年   33796篇
  1985年   32219篇
  1984年   23970篇
  1983年   20842篇
  1982年   12369篇
  1981年   10909篇
  1980年   10185篇
  1979年   22652篇
  1978年   15881篇
  1977年   13722篇
  1976年   12960篇
  1975年   14185篇
  1974年   16693篇
  1973年   16079篇
  1972年   15330篇
  1971年   14245篇
  1970年   13226篇
  1969年   12751篇
  1968年   11993篇
  1967年   10481篇
排序方式: 共有10000条查询结果,搜索用时 62 毫秒
101.
This meta-analysis focuses on the accuracy of upgrading to clinically significant prostate cancer (PCa) by multiparametric magnetic resonance imaging-targeted biopsy (MRI-TB) versus systematic biopsy (SB). We searched the Medline, Embase, Cochrane Central Register of Controlled Trials, Web of Science, Scopus, and Literatura Latino Americana em Ciências da Saúde databases through January 2020 for comparative, retrospective/prospective, paired-cohort, and randomized clinical trials with paired comparisons. The population consisted of patients with low-risk PCa in active surveillance with at least 1 index lesion on imaging. We evaluated the quality of evidence by using the Quality Assessment of Diagnostic Accuracy Studies-2 score. Group comparisons considered the differences between the area under the curve summary receiver operating characteristic curve in a 2-tailed method. We also compared the positive predictive value of the best single method (MRI-TB or SB) and the referral study test (combined biopsy, a combination of MRI-TB and SB). The meta-analysis included 6 studies enrolling 741 patients. The pooled sensitivity for the 2 groups was 0.79 (95% confidence interval, 0.74-0.83; I2 = 75%) and 0.67 (95% confidence interval, 0.63-0.74; I2 = 55.4%), respectively. The area under the curve for the MRI-TB and SB groups were 0.99 and 0.92 (P < .001), respectively. The positive predictive value for the MRI-TB and combined biopsy groups were similar. The accumulated evidence suggests better results for MRI-TB compared with SB. Therefore, use of MRI-TB alone may be preferable in patients in active surveillance harboring low-risk PCa.  相似文献   
102.
S. G. Brearley  S. Varey  A. Krige 《Anaesthesia》2023,78(10):1249-1255
Adequate postoperative analgesia is a key element of enhanced recovery programmes. Thoracic epidural analgesia is associated with superior postoperative analgesia but can lead to complications. Rectus sheath catheter analgesia may provide an alternative. In a nested qualitative study (within a two-year randomised controlled trial) focussing on the acceptability, expectations and experiences of receiving the interventions, participants (n = 20) were interviewed 4 weeks post-intervention using a grounded theory approach. Constant comparative analysis, with patient and public involvement, enabled emerging findings to be pursued through subsequent data collection. We found no notable differences regarding postoperative acceptability or the experience of pain management. Pre-operatively, however, thoracic epidural analgesia was a source of anticipatory fear and anxiety. Both interventions resulted in some experienced adverse events (proportionately more with thoracic epidural analgesia). Participants had negative experiences of the insertion of thoracic epidural analgesia; others receiving the rectus sheath catheter lacked confidence in staff members' ability to manage the local anaesthetic infusion pump. The anticipation of the technique of thoracic epidural analgesia, and concerns about its impact on mobility, represented an additional, unpleasant experience for patients already managing an illness experience, anticipating a life-changing operation and dealing with concerns about the future. The anticipation of rectus sheath catheter analgesia was not associated with such anxieties. Patients' experiences start far earlier than the experience of the intervention itself through anticipatory anxieties and fears about receiving a technique and its potential implications. Complex pain packages can take on greater meaning than their actual efficacy in relieving postoperative pain. Future research into patient acceptability and experience should not focus solely on efficacy of pain relief but should include anticipatory fears, anxieties and experiences.  相似文献   
103.
104.
105.
ObjectiveIdentify factors associated with healthcare providers' frequency of depot medroxyprogesterone acetate (DMPA) provision to adolescents.Study designWe analyzed data from surveys mailed to a nationally representative sample of public-sector providers and office-based physicians (n=1984). We estimated adjusted odds ratios (aORs) and 95% confidence intervals (CIs) of factors associated with frequent DMPA provision to adolescents in the past year.ResultsAlthough most providers (>95%) considered DMPA safe for adolescents, fewer reported frequent provision (89% of public-sector providers; 64% of office-based physicians). Among public-sector providers, factors associated with lower odds of frequent provision included working in settings without Title X funding (aOR 0.44, 95% CI 0.30–0.64), reporting primary care as their primary clinical focus versus reproductive or adolescent health (aOR 0.42, 95% CI 0.28–0.61), and providing fewer patients with family planning services. Among office-based physicians, factors associated with lower odds of frequent provision included specializing in obstetrics/gynecology (aOR 0.50, 95% CI 0.27–0.91) and family medicine (aOR 0.21, 95% CI 0.09–0.47) versus adolescent medicine, completing training ≥15 versus <5 years ago (aOR 0.27, 95% CI 0.09–0.83), and reporting that 0–24% of patients pay with Medicaid or other government healthcare assistance versus ≥50% (aOR 0.23, 95% CI 0.09–0.61). The reason most commonly reported by providers for infrequent DMPA provision was patient preference for another method.ConclusionsWhile most providers reported frequently providing DMPA to adolescents, training on evidence-based recommendations for contraception, focused on subgroups of providers with lower odds of frequent DMPA provision, may increase adolescents' access to contraception.ImplicationsAlthough >95% of providers considered depot medroxyprogesterone (DMPA) a safe contraceptive for adolescents, only 89% of public-sector providers and 64% of office-based physicians reported frequently providing DMPA to adolescents. Provider training on evidence-based recommendations for contraception counseling and provision may increase adolescents' access to DMPA and all methods of contraception.  相似文献   
106.
107.
108.
Background: Most theoretical models of self-determination suggest that both environmental and personal factors influence the development of self-determination. The design and implementation of interventions must be conducted with foreknowledge of such mediating and moderating factors if the intervention is to be successful.

Methods: The purpose of this study was to examine the degree to which several personal factors and school characteristics affect and explain students’ self-determination. A total of 232 students with intellectual disability from Spain participated. Their self-determination level was assessed by the ARC-INICO Scale.

Results: Students with moderate levels of intellectual disability obtained significantly lower scores on self-determination than their peers with mild intellectual disability. There were significant differences in relation to the level of support needs and their experience with transition programs. The level of support needs was a significant predictor.

Conclusion: These findings contribute to current research in this field and practical implications were discussed.  相似文献   

109.
International Journal of Clinical Pharmacy - Background Drug-related problems (DRP) following hospital discharge may cause morbidity, mortality and hospital re-admissions. It is unclear whether a...  相似文献   
110.
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