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   1436篇
  免费   87篇
  国内免费   2篇
耳鼻咽喉   11篇
儿科学   70篇
妇产科学   23篇
基础医学   138篇
口腔科学   33篇
临床医学   145篇
内科学   211篇
皮肤病学   14篇
神经病学   62篇
特种医学   175篇
外科学   262篇
综合类   15篇
预防医学   142篇
眼科学   124篇
药学   65篇
肿瘤学   35篇
  2021年   17篇
  2020年   13篇
  2019年   17篇
  2018年   29篇
  2017年   13篇
  2016年   19篇
  2015年   17篇
  2014年   33篇
  2013年   51篇
  2012年   41篇
  2011年   46篇
  2010年   56篇
  2009年   46篇
  2008年   48篇
  2007年   45篇
  2006年   33篇
  2005年   49篇
  2004年   63篇
  2003年   46篇
  2002年   55篇
  2001年   38篇
  2000年   36篇
  1999年   37篇
  1998年   47篇
  1997年   37篇
  1996年   34篇
  1995年   33篇
  1994年   34篇
  1993年   27篇
  1992年   30篇
  1991年   36篇
  1990年   30篇
  1989年   27篇
  1988年   27篇
  1987年   28篇
  1986年   27篇
  1985年   26篇
  1984年   13篇
  1983年   15篇
  1982年   22篇
  1981年   16篇
  1980年   12篇
  1978年   9篇
  1977年   14篇
  1976年   22篇
  1975年   18篇
  1974年   10篇
  1969年   12篇
  1967年   8篇
  1966年   9篇
排序方式: 共有1525条查询结果,搜索用时 15 毫秒
1.
Abstract Observations on the effect of unemployment on health include note that the clustering in certain geographic areas of low income, job insecurity and poor housing are the experience of the same groups of people. Considerable difficulties exist in isolating the different aspects involved. Nonetheless, it is argued (1) that the effects of each separate strand are dependent upon and reinforced by the others; (2) that it is possible to clarify the ways in which the elements interrelate; and (3) that it is the whole pattern that most satisfactorily explains currently available data on unemployment and health.  相似文献   
2.
Orbital exenteration at the Mayo Clinic. 1967-1986   总被引:2,自引:0,他引:2  
Orbital exenteration was performed in 102 patients at the Mayo Clinic during the 20-year period from 1967 through 1986. The surgical procedure was performed for mucormycosis in one patient and for pain and deformity after a severe facial burn in another; in the remaining 100 patients, exenteration was used to treat a neoplastic disorder. Although 19 different neoplasms were encountered, squamous cell carcinoma, basal cell carcinoma, and melanoma constituted 70% of the total. In 82 patients with no known residual tumor or metastases at operation, the 1-year survival rate was 88.6%, the 5-year rate was 56.8%, and the 5-year rate free of recurrence or metastases was 48.3%. In 18 patients with known residual tumor or metastases at exenteration, 55.0% were alive 1 year postoperatively, and the 5-year survival rate was 25.8%. Unusual findings in this series included two patients with metastatic basal cell carcinoma and one patient with a metastatic thyroid Hürthle cell carcinoma.  相似文献   
3.
Acute appendicitis: CT and US correlation in 100 patients   总被引:19,自引:1,他引:18  
  相似文献   
4.
Results of clinical, contrast enema (CE), and computed tomographic (CT) examinations in 39 patients with perforated colorectal neoplasms were retrospectively reviewed. Twenty patients were toxemic at initial presentation, but in only four patients was the diagnosis of perforated colorectal neoplasm initially suspected clinically. CE study was performed in 22 patients and enabled the diagnosis of perforated neoplasm in 11 cases, neoplasm alone in eight, and neither neoplasm nor perforation in three. CT was performed in 38 patients and enabled the diagnosis of perforated neoplasm in 36; pericolic phlegmon but no mass lesion was evident in two. In 16 patients, CT also demonstrated metastatic disease. Because of its reliability in establishing the diagnosis and staging the extent of the inflammatory and neoplastic disease, CT is indicated in cases of suspected or proved perforated colorectal neoplasm and in cases in which CE study findings are indeterminate or suggestive of perforated neoplasm.  相似文献   
5.
6.
7.
8.
John Milton (1608–1674) often has been regarded as the greatest poet of his time, yet he did not compose his most famous work,Paradise Lost, until after he had become blind in both eyes. On the basis of clues in Milton's writings, several possible diagnoses have been advanced to explain his loss of vision. The evidence for and against each theory is presented.  相似文献   
9.
Crosslineage T-cell receptor delta (TCR delta) rearrangements are widely used as tumor markers for the follow up of minimal residual disease in childhood B-precursor acute lymphoblastic leukemia (ALL) by polymerase chain reaction (PCR). The major drawback of this approach is the risk of false-negative results due to clonal evolution. We investigated the stability of V delta 2D delta 3 rearrangements in a group of 56 childhood B-precursor ALL patients by PCR and Southern blot analysis. At the PCR level, V delta 2D delta 3-to-J alpha rearranged subclones (one pathway for secondary TCR delta recombination) were demonstrated in 85.2% of V delta 2D delta 3-positive patients tested, which showed that small subclones are present in the large majority of patients despite apparently monoclonal TCR delta Southern blot patterns. Sequence analysis of V delta 2D delta 3J alpha rearrangements showed a biased J alpha gene usage, with HAPO5 and J alpha F in 26 of 32 and 6 of 32 clones, respectively. Comparison of V delta 2D delta 3 rearrangement status between diagnosis and first relapse showed differences in seven of eight patients studied. In contrast, from first relapse onward, no clonal changes were observed in six patients studied. To investigate the occurrence of crosslineage TCR delta rearrangements in normal B and T cells, fluorescence-activated cell sorter-sorted peripheral blood CD19+/CD3- and CD19-/CD3+ cell populations from three healthy donors were analyzed. V delta 2D delta 3 rearrangements were detected at low frequencies in both B and T cells, which suggests that V delta 2-to-D delta 3 joining also occurs during normal B-cell differentiation. A model for crosslineage TCR delta rearrangements in B-precursor ALL is deduced that explains the observed clonal changes between diagnosis and relapse and is compatible with multistep leukemogenesis of B-precursor ALL.  相似文献   
10.
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