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   379092篇
  免费   24940篇
  国内免费   2805篇
耳鼻咽喉   5193篇
儿科学   8223篇
妇产科学   10085篇
基础医学   53246篇
口腔科学   11831篇
临床医学   30094篇
内科学   78526篇
皮肤病学   8577篇
神经病学   27223篇
特种医学   13925篇
外国民族医学   82篇
外科学   60672篇
综合类   9952篇
现状与发展   1篇
一般理论   64篇
预防医学   17396篇
眼科学   9491篇
药学   31012篇
  1篇
中国医学   2191篇
肿瘤学   29052篇
  2021年   2634篇
  2019年   2754篇
  2018年   4553篇
  2017年   3451篇
  2016年   3549篇
  2015年   4049篇
  2014年   5727篇
  2013年   7405篇
  2012年   10071篇
  2011年   10265篇
  2010年   6232篇
  2009年   5878篇
  2008年   9486篇
  2007年   10365篇
  2006年   10273篇
  2005年   9322篇
  2004年   8838篇
  2003年   8571篇
  2002年   8236篇
  2001年   28298篇
  2000年   28819篇
  1999年   23692篇
  1998年   5182篇
  1997年   4260篇
  1996年   3848篇
  1995年   3492篇
  1994年   3116篇
  1993年   2850篇
  1992年   16075篇
  1991年   14838篇
  1990年   14166篇
  1989年   13975篇
  1988年   12592篇
  1987年   12073篇
  1986年   11124篇
  1985年   10340篇
  1984年   6915篇
  1983年   5610篇
  1982年   2718篇
  1979年   5484篇
  1978年   3346篇
  1977年   2967篇
  1975年   2638篇
  1974年   3070篇
  1973年   2866篇
  1972年   2831篇
  1971年   2783篇
  1970年   2516篇
  1969年   2547篇
  1968年   2253篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
31.
Zygomatic implant treatment is widely applied for severe maxillary atrophy to help rehabilitate the maxillary dentition. This retrospective study was performed to evaluate the actual radiographic bone–implant contact (rBIC) lengths of zygomatic implants. The records of 28 patients who underwent zygomatic implant surgery and subsequent follow-up examinations between August 2013 and September 2018 in the Department of Oral and Maxillofacial Surgery, Taipei Tzu Chi Hospital were reviewed. The surgeries were performed by a single surgeon using the same treatment protocol. All patients had a computed tomography scan at 1 year after the surgery. Using three-dimensional imaging software, an investigator measured the rBIC lengths of 66 implants and documented their clinical status. The implant survival rate was 100%. The mean rBIC length was significantly longer in male patients than in female patients (20.80 ± 5.88 mm versus 17.79 ± 6.34 mm; P = 0.028). The mean rBIC length of double zygomatic implants was significantly longer when compared to that of single implants (21.11 ± 6.23 mm versus 17.75 ± 5.85 mm; P = 0.027). This article is novel in reporting the exact rBIC lengths of zygomatic implants in a clinical setting. The results showed that zygomatic implants are a viable treatment modality for full-mouth rehabilitation.  相似文献   
32.
33.
34.
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   
35.
Prevention Science - This study aimed to evaluate the effectiveness of the drug and violence resistance educational program (PROERD) on short-term secondary outcomes, such as intentions to use...  相似文献   
36.
37.
38.
39.
40.
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