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   418篇
  免费   11篇
  国内免费   35篇
耳鼻咽喉   30篇
儿科学   13篇
妇产科学   26篇
基础医学   34篇
口腔科学   4篇
临床医学   55篇
内科学   116篇
皮肤病学   2篇
神经病学   10篇
特种医学   53篇
外科学   34篇
综合类   7篇
预防医学   15篇
眼科学   2篇
药学   40篇
肿瘤学   23篇
  2023年   1篇
  2021年   3篇
  2020年   4篇
  2019年   3篇
  2018年   10篇
  2017年   3篇
  2016年   8篇
  2015年   9篇
  2014年   4篇
  2013年   18篇
  2012年   5篇
  2011年   11篇
  2010年   9篇
  2009年   17篇
  2008年   18篇
  2007年   34篇
  2006年   16篇
  2005年   22篇
  2004年   21篇
  2003年   9篇
  2002年   11篇
  2001年   6篇
  2000年   8篇
  1999年   9篇
  1998年   17篇
  1997年   14篇
  1996年   18篇
  1995年   18篇
  1994年   16篇
  1993年   22篇
  1992年   12篇
  1991年   12篇
  1990年   13篇
  1989年   13篇
  1988年   9篇
  1987年   6篇
  1986年   4篇
  1985年   7篇
  1984年   4篇
  1983年   3篇
  1982年   4篇
  1981年   3篇
  1980年   2篇
  1979年   3篇
  1978年   2篇
  1976年   2篇
  1975年   1篇
排序方式: 共有464条查询结果,搜索用时 15 毫秒
81.
Hypersensitivity pneumonitis: evaluation with CT   总被引:4,自引:0,他引:4  
Silver  SF; Muller  NL; Miller  RR; Lefcoe  MS 《Radiology》1989,173(2):441-445
Thirteen chest radiographs and computed tomographic (CT) scans obtained from 11 patients with hypersensitivity pneumonitis were reviewed. The CT findings were correlated with open lung biopsy findings in seven patients. The two patients with acute hypersensitivity pneumonitis showed air-space opacification on CT scans. An open lung biopsy, done in one of these patients, demonstrated noncaseating granulomas and filling of the air spaces with macrophages. The nine patients with subacute hypersensitivity pneumonitis showed small, rounded opacities and patchy air-space opacification on CT scans. These findings reflected the histologic findings, which consisted of interstitial pneumonitis, cellular bronchiolitis, and small, noncaseating granulomas. The six patients with symptoms for 12 months or longer also showed irregular linear opacities on CT scans, corresponding to areas of fibrosis. CT scans were superior to radiographs in helping to assess the type and extent of abnormalities, and high-resolution CT scans were superior to conventional CT scans.  相似文献   
82.
DNA microarray technology for neonatal screening   总被引:2,自引:0,他引:2  
Modern molecular biology, owing much to the Human Genome Initiative, has elucidated many of the genetic mechanisms underlying heritable metabolic disease. While the use of molecular methods has flourished in research laboratories, complexity and cost have limited their utility in newborn screening. Newborn blood cards provide high quality DNA samples able to provide reliable support to highly multiplexed polymerase chain reactions (PCR). New manufacturing processes have reduced the cost of DNA microarray technology to the point where it is a practical tool for population screening. In a single assay, a DNA microarray facilitates the co-detection of amplification products diagnostic for several genetic diseases. High throughput is achieved with automation at every step, from DNA extraction to detection of hybrids. We suggest that it is both feasible and practical to develop a first-tier newborn screening protocol based upon multiplex PCR and analysis of amplification products using DNA microarrays. Initial data utilizing the model systems of sickle cell disease, α-1-antitrypsin deficiency and Factor V Leiden will be reported.  相似文献   
83.
84.
85.
Objective: To evaluate differences in distribution of estimated fetal weight (EFW) and birth weight (BW) of ongoing fetuses and neonates of the same gestational age.

Methods: Reference curves for EFW (Hadlock BPD-HC-AC-FL formula, N?=?1191) and BW (N?=?1036) in singleton pregnancies from 24+0 to 40+6 gestational weeks were calculated. Multiple pregnancies, fetuses with major or multiple abnormalities or syndromes and iatrogenic preterm deliveries due to preeclampsia or abnormal fetal Doppler were excluded. The standardized residuals for EFW and BW were calculated and compared.

Results: EFW and BW can be accurately described by quadratic equations (R2?=?0.944 and 0.807, respectively). The distribution of standardized residuals for BW using the EFW formula was negative from 28+0 to 35+6 weeks. The 50th and 5th centiles of BW were lower than those of EFW throughout prematurity, and they converged at approximately 38 gestational weeks. The 5th centile for BW was 30% lower than the 5th centile for EFW at 27 weeks, 27.5% lower at 30 weeks and 19.4% at 34 weeks.

Conclusions: Preterm infants have lower BW distribution compared to the expected EFW of ongoing pregnancies of the same gestational age, supporting the concept of hidden intrauterine morbidity for a proportion of these infants.  相似文献   
86.
87.
口咽鳞癌的临床处理仍存在争议,该文对口咽癌患者应用原发灶手术切除、颈淋巴清扫及术后行放疗的效果进行总结。对复合标准的211例患者进行回顾性研究。应用Kaplan—Meier曲线计算总生存率及无瘤生存率,应用单变量及多变量统计学分析研究疾病的临床特点与预后的关系。2年及5年的无瘤生存率分别为79.8%和68.8%.单因素分析表明,肿瘤切缘阳性是无瘤生存率重要也是唯一的预后因素。  相似文献   
88.
89.
90.
患者为1例39岁女性,患T/NK细胞淋巴瘤,在外周血异基因干细胞移植后15天,发生环孢素A(CSA)毒性相关的微血管病溶血性贫血(MAHA).因血清肌酐从移植前的0.4mg/dL,上升至移植后第9和15天的1.0和2.9 mg/dL.故停用CSA.  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