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   4982篇
  免费   196篇
  国内免费   65篇
耳鼻咽喉   152篇
儿科学   217篇
妇产科学   111篇
基础医学   425篇
口腔科学   568篇
临床医学   257篇
内科学   711篇
皮肤病学   64篇
神经病学   376篇
特种医学   156篇
外科学   472篇
综合类   357篇
预防医学   403篇
眼科学   474篇
药学   345篇
  3篇
中国医学   76篇
肿瘤学   76篇
  2024年   3篇
  2023年   160篇
  2022年   237篇
  2021年   346篇
  2020年   283篇
  2019年   312篇
  2018年   299篇
  2017年   171篇
  2016年   137篇
  2015年   121篇
  2014年   399篇
  2013年   306篇
  2012年   266篇
  2011年   329篇
  2010年   245篇
  2009年   209篇
  2008年   188篇
  2007年   158篇
  2006年   133篇
  2005年   134篇
  2004年   98篇
  2003年   87篇
  2002年   61篇
  2001年   46篇
  2000年   42篇
  1999年   62篇
  1998年   51篇
  1997年   46篇
  1996年   20篇
  1995年   28篇
  1994年   25篇
  1993年   20篇
  1992年   29篇
  1991年   26篇
  1990年   12篇
  1989年   11篇
  1988年   11篇
  1987年   9篇
  1986年   6篇
  1985年   25篇
  1984年   28篇
  1983年   14篇
  1982年   6篇
  1981年   12篇
  1980年   13篇
  1979年   5篇
  1978年   3篇
  1977年   3篇
  1975年   3篇
  1973年   2篇
排序方式: 共有5243条查询结果,搜索用时 15 毫秒
1.
《Orthopaedics and Trauma》2022,36(6):304-310
Congenital vertical talus (CVT) is a rare foot deformity that presents with a rigid flat foot at birth. CVT can present as an isolated abnormality in the newborn, however in at least 50% of cases in association with other conditions. Full neuro-axial imaging is essential to detect any associated neurologic problems. Radiographs of the foot, including forced plantar and dorsiflexion laterals, are diagnostic. Gold standard modern treatment uses the Dobbs method of serial manipulation and casting with minimally-invasive stabilization of the talonavicular joint and Achilles tendon tenotomy.  相似文献   
2.
PurposeThe purpose of this study was to determine whether computed tomography (CT)-based machine learning of radiomics features could help distinguish autoimmune pancreatitis (AIP) from pancreatic ductal adenocarcinoma (PDAC).Materials and MethodsEighty-nine patients with AIP (65 men, 24 women; mean age, 59.7 ± 13.9 [SD] years; range: 21–83 years) and 93 patients with PDAC (68 men, 25 women; mean age, 60.1 ± 12.3 [SD] years; range: 36–86 years) were retrospectively included. All patients had dedicated dual-phase pancreatic protocol CT between 2004 and 2018. Thin-slice images (0.75/0.5 mm thickness/increment) were compared with thick-slices images (3 or 5 mm thickness/increment). Pancreatic regions involved by PDAC or AIP (areas of enlargement, altered enhancement, effacement of pancreatic duct) as well as uninvolved parenchyma were segmented as three-dimensional volumes. Four hundred and thirty-one radiomics features were extracted and a random forest was used to distinguish AIP from PDAC. CT data of 60 AIP and 60 PDAC patients were used for training and those of 29 AIP and 33 PDAC independent patients were used for testing.ResultsThe pancreas was diffusely involved in 37 (37/89; 41.6%) patients with AIP and not diffusely in 52 (52/89; 58.4%) patients. Using machine learning, 95.2% (59/62; 95% confidence interval [CI]: 89.8–100%), 83.9% (52:67; 95% CI: 74.7–93.0%) and 77.4% (48/62; 95% CI: 67.0–87.8%) of the 62 test patients were correctly classified as either having PDAC or AIP with thin-slice venous phase, thin-slice arterial phase, and thick-slice venous phase CT, respectively. Three of the 29 patients with AIP (3/29; 10.3%) were incorrectly classified as having PDAC but all 33 patients with PDAC (33/33; 100%) were correctly classified with thin-slice venous phase with 89.7% sensitivity (26/29; 95% CI: 78.6–100%) and 100% specificity (33/33; 95% CI: 93–100%) for the diagnosis of AIP, 95.2% accuracy (59/62; 95% CI: 89.8–100%) and area under the curve of 0.975 (95% CI: 0.936–1.0).ConclusionsRadiomic features help differentiate AIP from PDAC with an overall accuracy of 95.2%.  相似文献   
3.
4.
5.
6.
7.
8.
BackgroundThere is limited information about the long-term outcome of obstructive sleep apnea (OSA) diagnosed in children and adolescents for educational and social factors. Here, we estimate the long-term socioeconomic outcome and health care costs of OSA.MethodsThe historical case-control cohort study included Danish individuals with OSA diagnosed in childhood or adolescence between 1994 and 2015. Health care costs and socioeconomic data were obtained from nationwide administrative and health registers. A total of 5419 were diagnosed during this period; of these we traced 1004 patients who we compared with 4085 controls (mean index age, 10.2 years; Standard Deviation (SD), 5.6 years) until the age of 20 years. Controls were matched for age, gender, and residency.ResultsComparing the OSA patient and control groups at age 20 years we found: 1) lower parental educational level; 2) significantly lower educational level also after adjustment for parental educational level; 3) lower school grade-point averages; 4) lower employment rate and lower income, which was not fully compensated when transfer payments were considered; and 5) patients' initial health care costs were higher due to higher morbidity. Patients showed higher mortality rates than controls (Hazard Ratio (HR) = 7.63, 95% CI = 4.87–11.95, P < 0.001).ConclusionsOSA in children and adolescent is associated with a significant influence on morbidity, mortality, educational level, grading, social outcome, and welfare consequences.  相似文献   
9.
10.
《Vaccine》2020,38(39):6141-6152
Influenza vaccination is considered the most valuable means to prevent and control seasonal influenza infections, which causes various clinical symptoms, ranging from mild cough and fever to even death. Among various influenza vaccine types, the inactivated subunit type is known to provide improved safety with reduced reactogenicity. However, there are some drawbacks associated with inactivated subunit type vaccines, with the main ones being its low immunogenicity and the induction of Th2-biased immune responses. In this study, we investigated the role of a single-stranded RNA (ssRNA) derived from the intergenic region in the internal ribosome entry site of the Cricket paralysis virus as an adjuvant rather than the universal vaccine for a seasonal inactivated subunit influenza vaccine. The ssRNA adjuvant stimulated not only well-balanced cellular (indicated by IgG2a, IFN-γ, IL-2, and TNF-α) and humoral (indicated by IgG1 and IL-4) immune responses but also a mucosal immune response (indicated by IgA), a key protector against respiratory virus infections. It also increases the HI titer, the surrogate marker of influenza vaccine efficacy. Furthermore, ssRNA adjuvant confers cross-protective immune responses against heterologous influenza virus infection while promoting enhanced viral clearance. Moreover, ssRNA adjuvant increases the number of memory CD4+ and CD8+ T cells, which can be expected to induce long-term immune responses. Therefore, this ssRNA-adjuvanted seasonal inactivated subunit influenza vaccine might be the best influenza vaccine generating robust humoral and cellular immune responses and conferring cross-protective and long-term immunity.  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