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   1691513篇
  免费   126470篇
  国内免费   3774篇
耳鼻咽喉   21729篇
儿科学   55607篇
妇产科学   46153篇
基础医学   241207篇
口腔科学   48728篇
临床医学   151147篇
内科学   333149篇
皮肤病学   38655篇
神经病学   131097篇
特种医学   63859篇
外国民族医学   242篇
外科学   257197篇
综合类   38922篇
现状与发展   4篇
一般理论   531篇
预防医学   124080篇
眼科学   40157篇
药学   123578篇
  7篇
中国医学   4477篇
肿瘤学   101231篇
  2021年   12786篇
  2019年   13529篇
  2018年   19957篇
  2017年   15216篇
  2016年   16611篇
  2015年   18960篇
  2014年   26217篇
  2013年   37956篇
  2012年   52742篇
  2011年   55426篇
  2010年   32777篇
  2009年   30703篇
  2008年   51524篇
  2007年   54808篇
  2006年   55266篇
  2005年   52541篇
  2004年   50745篇
  2003年   48150篇
  2002年   46373篇
  2001年   91785篇
  2000年   93609篇
  1999年   76964篇
  1998年   19717篇
  1997年   17268篇
  1996年   17393篇
  1995年   16745篇
  1994年   15291篇
  1993年   14075篇
  1992年   57386篇
  1991年   55274篇
  1990年   52975篇
  1989年   50748篇
  1988年   46132篇
  1987年   44939篇
  1986年   42229篇
  1985年   39988篇
  1984年   29350篇
  1983年   24909篇
  1982年   13899篇
  1979年   25531篇
  1978年   17575篇
  1977年   14907篇
  1976年   13874篇
  1975年   14563篇
  1974年   17630篇
  1973年   16944篇
  1972年   15673篇
  1971年   14453篇
  1970年   13431篇
  1969年   12517篇
排序方式: 共有10000条查询结果,搜索用时 156 毫秒
911.
Juvenile-onset acid maltase deficiency with unusual familial features   总被引:2,自引:0,他引:2  
From early childhood, two brothers had mild gait difficulties due to acid maltase deficiency (AMD). Biochemical studies of family members were consistent with autosomal recessive inheritance, but the asymptomatic mother had AM activity in the homozygote range, and her parents had decreased AM activity. The asymptomatic mother may be homozygous for the adult-onset variant of AMD. Alternatively, either the mother or the children may be genetic compounds of the childhood and adult forms of AMD.  相似文献   
912.
913.
914.
Forty-one multiplex families, from published sources and new data from the National Cancer Institute, segregating for Hodgkin's disease and HLA, have been studied. A reanalysis of these data strongly suggests a recessive mode of inheritance for susceptibility to Hodgkin's disease. The HLA haplotype sharing data between affected relatives demonstrate that approximately 60% of cases in multiplex families are due to an HLA-linked susceptibility gene, the remaining 40% being due to other familial factors. The data clearly support the hypothesis of etiological heterogeneity for Hodgkin's disease, with both HLA-linked and HLA-unlinked factors being responsible. Finally, there is an increased concordance of histological types between affected relatives, but this concordance seems independent of HLA sharing.  相似文献   
915.
A combination of Photo Radiation Therapy (PRT) using Argon-Dye Laser with hematoporphyrin derivatives (HpD) was used experimentally on a cytogenetically highly malignant neuroblastoma xenograft, which exhibited a homogeneously staining region and caused DNA amplifications in chromosomes. The tumor tissue was treated with 500 joules/cm2 of laser. The dosage of HpD was 50 mg per kg body weight. Necrosis of over 50% of the tumor was observed in half the specimens. Swollen cytoplasmic organelles and ruptured cell and nuclear membranes were observed by electron microscopy after PRT. PRT may be used with other treatment modalities for the removal of residual and metastatic tumors.  相似文献   
916.
Traumatic infarction of the spinal cord in children   总被引:2,自引:0,他引:2  
Infarction of the spinal cord in childhood is rarely due to trauma. During a 15-year period (1971 to 1985), eight children were admitted to The Hospital for Sick Children, Toronto, with a diagnosis of traumatic infarction of the spinal cord. All of these patients had delayed onset of neurological signs varying between 2 hours and 4 days after their initial trauma. No bone abnormalities were seen on plain spine x-ray films. Myelography was carried out in seven of these children and found to be normal in all seven. Six patients who were paraplegic at the time of admission remained permanently paraplegic, but two with incomplete cord signs did show some improvement.  相似文献   
917.
918.
919.
920.
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