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   786篇
  免费   39篇
  国内免费   29篇
耳鼻咽喉   6篇
儿科学   27篇
妇产科学   12篇
基础医学   80篇
口腔科学   59篇
临床医学   82篇
内科学   151篇
皮肤病学   8篇
神经病学   20篇
特种医学   29篇
外科学   140篇
综合类   29篇
预防医学   84篇
眼科学   4篇
药学   90篇
中国医学   3篇
肿瘤学   30篇
  2023年   12篇
  2022年   22篇
  2021年   36篇
  2020年   23篇
  2019年   26篇
  2018年   28篇
  2017年   23篇
  2016年   20篇
  2015年   15篇
  2014年   31篇
  2013年   43篇
  2012年   56篇
  2011年   63篇
  2010年   40篇
  2009年   33篇
  2008年   33篇
  2007年   43篇
  2006年   41篇
  2005年   37篇
  2004年   27篇
  2003年   26篇
  2002年   18篇
  2001年   16篇
  2000年   12篇
  1999年   8篇
  1998年   5篇
  1997年   4篇
  1996年   10篇
  1995年   11篇
  1993年   9篇
  1992年   5篇
  1991年   6篇
  1990年   6篇
  1989年   9篇
  1987年   9篇
  1986年   4篇
  1985年   3篇
  1983年   4篇
  1982年   6篇
  1980年   5篇
  1979年   7篇
  1978年   2篇
  1977年   1篇
  1976年   1篇
  1975年   3篇
  1974年   2篇
  1973年   1篇
  1972年   1篇
  1971年   3篇
  1969年   1篇
排序方式: 共有854条查询结果,搜索用时 359 毫秒
161.
Globally, there is increasing emphasis on value-based cancer care. Rising healthcare costs and reduced health care spending and budgets, especially in low- and middle-income countries (LMICs), call for patients, providers, and healthcare systems to apply the Choose Wisely (CW) approach. This approach seeks to advance a dialogue on avoiding unnecessary medical tests, treatments, and procedures. Several factors have been described as barriers and facilitators to the implementation of the Choosing Wisely recommendations in high-income countries but none for LMICs. In this review, we attempt to classify potential barriers to the Choose Wisely implementation relative to the sources of behavior and potential intervention functions that can be implemented in order to reduce these barriers.  相似文献   
162.
ObjectiveTo quantify dentoskeletal changes accompanying the use of extrusion arches during the treatment of anterior open bite (AOB) in adults.Materials and MethodsA total of 23 adult patients with an AOB of −3.05 mm ± 1.27 mm were treated with upper and lower extrusion arches after the alignment phase. Lateral cephalograms were taken before placement of the extrusion arch, immediately after closure of the open bite (T2), and at the end of orthodontic treatment (T3). Data were statistically analyzed using repeated-measures analysis of variance and the Bonferroni post hoc test for pairwise comparisons (α = 0.05).ResultsSuccessful closure of AOB, with an overall change in overbite of 4.73 ± 1.93 mm, was achieved in an average of 3.8 months and remained stable at T3. Upper and lower incisors were significantly extruded by 2.05 mm ± 0.72 mm and 2.54 mm ± 1.63 mm, respectively, and significantly retroclined by 6.36° ± 1.63° and 8.45° ± 3.83°, respectively, with a resultant increase in the interincisal angle of 12.80° ± 2.09°. Statistically significant intrusion and mesial tipping (P < .001) of the maxillary and mandibular first molars were observed at T2. Dentoskeletal changes remained stable at T3, except for a significant reduction of the mesial tipping of the maxillary and mandibular first molars.ConclusionsThe combined use of maxillary and mandibular extrusion arches resulted in significant favorable dentoskeletal changes that led to the successful closure of AOB during a short duration of treatment.  相似文献   
163.
AimThis study aimed at providing evidence to consider sex differences in interpretations of laboratory parameters of severe COVID-19 patients with diabetes.MethodsFor 118 diabetic patients, laboratory measurements and clinical outcomes were compared between males and females. This study also compared inflammatory ratios obtained from combinations of six inflammatory markers between the two groups. The risk factors for mortality were identified through logistic regression.ResultsMales were 54 (45.8%) and females were 64 (54.2%). Males showed a significant increase in ALT (P = 0.003), CRP (P = 0.03), mean platelet volume (MPV)-to-lymphocyte ratio (P = 0.001), and C-reactive protein-to-albumin ratio (P = 0.044), whereas females had a significant increase in lymphocytes (P < 0.005) and MPV (P = 0.01). In all participants, multivariate analysis illustrated that older age, male sex, increased serum total bilirubin, and decreased PO2 were significant independent predictors of mortality (P < 0.05).ConclusionIn severe COVID-19 patients with diabetes, there were significant sex differences in many laboratory characteristics with a higher risk of mortality among males.  相似文献   
164.
165.
166.

Background  

This study investigated the prevalence of Enterococcus faecalis, its putative virulence factors and antimicrobial susceptibility in individuals with and without dental diseases. A total of 159 oral rinse specimens were collected from patients (n = 109) suffering from dental diseases and healthy controls (n = 50).  相似文献   
167.
To elucidate immune pathogenic mechanisms in asbestosis, lung and spleen lymphoid cell populations were analyzed at defined time intervals (1, 2, 3, 6, and 12 weeks during exposure and 4, 24, and 48 weeks post-exposure) in asbestos-exposed and unexposed (control) mice. Polymorphonuclear leukocytes and macrophages were increased in the lung tissue histologic sections of asbestos-exposed mice compared to controls. No consistent changes were observed in percentages of lung or spleen helper, suppressor, or total lymphocyte populations after asbestos exposure. The numbers of B cells (identified by anti-IgG) in minced lung preparations of asbestos-exposed animals were increased after 12 weeks of exposure. There also was an increase in IgG production in asbestos-exposed mice after 12 weeks exposure and at 4 weeks post-exposure with a return to near baseline levels 24 and 48 weeks after initial exposure. Collectively, these studies demonstrate stimulatory effects of inhaled asbestos fibers on B cells and IgG production after 12 weeks of continuous inhalation of asbestos fibers in a dust generation chamber.  相似文献   
168.
The European Journal of Health Economics - Cancer treatment is a significant driver of healthcare costs worldwide, however, the economic impact of treating patients with anti-neoplastic agents is...  相似文献   
169.
The multidrug transporter P-glycoproteins are encoded by three multidrug-resistance (mdr) genes in rodents, designated mdr1a (mdr3), mdr1b (mdr1), and mdr2. Only the first two genes are functionally related to multidrug resistance. Activation of rodent mdr genes during liver regeneration and hepatocarcinogenesis has been reported. In mice, mdr1a is activated in hepatocellular carcinomas (HCCs) produced by various carcinogenic protocols, whereas both mdr1a and mdr2 are activated during liver regeneration. In this communication, we report isolating three gene-specific probes for the rat mdr homologues, which were used as probes in an RNase protection assay to demonstrate that mdr1b mRNA was expressed in HCCs induced by two different protocols. Furthermore, high levels of hepatic mdr1b mRNA but only moderate levels of mdr1a and mdr2 mRNA were seen in preneoplastic lesions in rats treated with 2-acetylaminofluorene. Likewise, highly elevated levels of hepatic mdr1b mRNA but only moderately increased levels of mdr1a and mdr2 mRNA were seen after partial hepatectomy. Nevertheless, the general patterns of tissue-specific expression of these three mdr genes were similar in rats and mice. These results reveal a complex hepatic gene expression pattern during hepatocarcinogenesis and hepatic proliferation for this conserved gene family in rodents.  相似文献   
170.
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