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   5844篇
  免费   268篇
  国内免费   40篇
耳鼻咽喉   47篇
儿科学   148篇
妇产科学   87篇
基础医学   655篇
口腔科学   127篇
临床医学   362篇
内科学   1471篇
皮肤病学   124篇
神经病学   432篇
特种医学   288篇
外科学   652篇
综合类   14篇
一般理论   1篇
预防医学   238篇
眼科学   141篇
药学   643篇
中国医学   17篇
肿瘤学   705篇
  2023年   29篇
  2022年   58篇
  2021年   93篇
  2020年   73篇
  2019年   76篇
  2018年   84篇
  2017年   88篇
  2016年   85篇
  2015年   91篇
  2014年   110篇
  2013年   131篇
  2012年   244篇
  2011年   252篇
  2010年   149篇
  2009年   133篇
  2008年   224篇
  2007年   285篇
  2006年   257篇
  2005年   295篇
  2004年   272篇
  2003年   229篇
  2002年   262篇
  2001年   199篇
  2000年   238篇
  1999年   222篇
  1998年   91篇
  1997年   73篇
  1996年   55篇
  1995年   51篇
  1994年   43篇
  1993年   49篇
  1992年   147篇
  1991年   133篇
  1990年   143篇
  1989年   142篇
  1988年   130篇
  1987年   123篇
  1986年   119篇
  1985年   123篇
  1984年   83篇
  1983年   50篇
  1982年   30篇
  1981年   27篇
  1980年   26篇
  1979年   47篇
  1978年   22篇
  1977年   22篇
  1975年   23篇
  1972年   20篇
  1969年   34篇
排序方式: 共有6152条查询结果,搜索用时 18 毫秒
81.
82.
83.
84.
85.
86.
87.
We examined dermoscopic features of three cases of extraocular sebaceous carcinoma and reviewed the literatures. The yellowish structures, polymorphous vessels and ulceration were common findings in our cases and all cases of the previous reports. The appearance of whitish‐pink areas has not been described previously. Our results suggested that the combination of four dermoscopic features, whitish‐pink areas, yellowish structures, polymorphous vessels and ulceration might be distinctive in extraocular sebaceous carcinoma.  相似文献   
88.
89.
Background: The frequency and causes of right ventricular (RV) systolic dysfunction early after cardiac transplantation are not well defined. Methods: We investigated the prevalence and causes of RV dysfunction in 27 heart transplant recipients, as measured by lateral tricuspid annular plane excursion (TAPSE) and fractional area change (FAC) at a mean of 15 ± 11 days after transplant. Tissue Doppler imaging was used to assess systolic time velocity integral (TVI) of the RV basal free wall. A subset of 22 patients had follow‐up TAPSE measurement at 406 ± 121 days. Results: RV systolic dysfunction, defined as TAPSE > 2 standard deviation (SD) below values in a control group, was present in 100% (27/27) of patients (P < 0.05). FAC was also significantly lower in patients compared with controls (P < 0.0001). TVI confirmed the presence of RV dysfunction in all 16 patients with both TAPSE and TVI (P < 0.05). Ischemic time (P = 0.017) and posttransplant tricuspid regurgitation (P = 0.024) were independent predictors of early RV dysfunction (r = 0.753). On follow‐up, RV function improved in 15 of 22 patients but all patients remained with TAPSE > 2 SD below controls. Conclusion: This study showed that 100% of patients had reduced RV function early after transplant. Two thirds of patients had partial recovery of RV function during the first year. In all patients, however, RV function remained significantly lower than in controls.  相似文献   
90.
Aseptic meningitis and acute parotitis have been observed after mumps vaccination. Mumps outbreaks have been reported in Japan because of low vaccine coverage, and molecular differentiation is required to determine whether these cases are vaccine associated. RT-nested PCR was performed in the small hydrophobic gene region, and viruses were differentiated by restriction fragment length polymorphism assay. A total of 584 nucleotides were amplified. The PCR product of the Hoshino strain was cut into two fragments (313 and 271 nucleotides) by MfeI; that of the Torii strain was digested with EcoT22I, resulting in 332- and 252-nucleotide fragments. Both strains were genotype B and had an XbaI site, resulting in two fragments: 299 and 285 nucleotides. Current circulating wild types were cut only by XbaI or MfeI. However, the MfeI site of the wild types was different from that of the Hoshino strain, resulting in 451- and 133-nucleotide fragments. Using three restriction enzymes, two mumps vaccine strains were distinguished from wild types, and this separation was applied to the identification of vaccine-related adverse events.  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