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   2630篇
  免费   135篇
  国内免费   5篇
耳鼻咽喉   41篇
儿科学   241篇
妇产科学   69篇
基础医学   252篇
口腔科学   55篇
临床医学   132篇
内科学   411篇
皮肤病学   57篇
神经病学   191篇
特种医学   84篇
外科学   391篇
综合类   323篇
现状与发展   1篇
一般理论   1篇
预防医学   96篇
眼科学   40篇
药学   167篇
  1篇
中国医学   6篇
肿瘤学   211篇
  2022年   27篇
  2021年   57篇
  2020年   28篇
  2019年   35篇
  2018年   53篇
  2017年   36篇
  2016年   48篇
  2015年   71篇
  2014年   68篇
  2013年   87篇
  2012年   122篇
  2011年   138篇
  2010年   139篇
  2009年   116篇
  2008年   138篇
  2007年   154篇
  2006年   135篇
  2005年   133篇
  2004年   115篇
  2003年   91篇
  2002年   81篇
  2001年   78篇
  2000年   68篇
  1999年   65篇
  1998年   45篇
  1997年   51篇
  1996年   41篇
  1995年   28篇
  1994年   28篇
  1993年   12篇
  1992年   38篇
  1991年   30篇
  1990年   25篇
  1989年   22篇
  1988年   34篇
  1987年   21篇
  1986年   20篇
  1985年   22篇
  1984年   15篇
  1983年   17篇
  1982年   20篇
  1981年   14篇
  1978年   24篇
  1977年   23篇
  1976年   16篇
  1975年   11篇
  1974年   21篇
  1973年   15篇
  1972年   16篇
  1970年   12篇
排序方式: 共有2770条查询结果,搜索用时 15 毫秒
51.
Basaloid squamous cell carcinoma is a rare variant of squamous cell carcinoma, Larynx has been an uncommon site of this tumour which is said to have aggressive biological behaviour with high incidence of cervical and distant metastasis along with second primary. Two cases of laryngeal basaloid squamous cell carcinoma are reported with relevant review of literature. The submucosal spread of tumour is highlighted alongwith role of preoperative radio therapy.  相似文献   
52.
Dibenzo[a,l]pyrene (DB[a,l]P), an environmental polycyclic aromatic hydrocarbon, is the most potent carcinogen ever tested in mouse skin and rat mammary gland. In this study, DB[a,l]P was examined for DNA adduction, tumorigenicity, and induction of Ki-ras oncogene mutations in tumor DNA in strain A/J mouse lung. Groups of mice received a single i.p. injection of 0.3, 1.5, 3.0, or 6.0 mg/kg DB[a,l]P in tricaprylin. Following treatment, DNA adducts were measured at times between 1 and 28 days, while tumors were counted at 250 days and analyzed for the occurrence of point mutations in codons 12 and 61 of the Ki-ras oncogene. DB[a,l]P in strain A/J mouse lung induced six major and four minor DNA adducts. Maximal levels of adduction occurred between 5 and 10 days after injection followed by a gradual decrease. DB[a,l]P-DNA adducts in lung tissue were derived from both anti- and syn-11,12- dihydroxy-13,14-epoxy- 11,12,13,14-tetrahydrodibenzo[a,l]pyrene (DB[a,l]PDE) and both deoxyadenosine (dAdo) and deoxyguanosine (dGuo) residues in DNA as revealed by cochromatography. The major adduct was identified as a product of the reaction of an anti-DB[a,l]PDE with dAdo in DNA. DB[a,l]P induced significant numbers of lung adenomas in a dose- dependent manner, with the highest dose (6.0 mg/kg) yielding 16.1 adenomas/mouse. In tricaprylin-treated control animals, there were 0.67 adenomas/mouse. Based on the administered dose, DB[a,l]P was more active than other environmental carcinogens including benzo[a]pyrene. As a function of time-integrated DNA adduct levels, DB[a,l]P induced lung adenomas with about the same potency as other PAHs, suggesting that the adducts formed by DB[a,l]P are similar in carcinogenic potency to other PAHs in the strain A/J mouse lung model. Analysis of the Ki- ras mutation spectrum in DB[a,l]P-induced lung tumors revealed the predominant mutations to be G-->T transversions in the first base of codon 12, A-->G transitions in the second base of codon 12, and A-->T transversions in the second or third base of codon 61, concordant with the DNA adduct profile.   相似文献   
53.
Twenty-seven patients with idiopathic palmoplanter hyperhidrosis were treated with Iontotherapy over a one year period. In twenty-four cases there was a good response but maintenance therapy was required every 3-4 weeks.KEY WORDS: Iontophoresis, Palmoplanter hyperhidrosis  相似文献   
54.
55.
Tracheoesophageal fistula is a life threatening condition. Patients not managed surgically ultimately die of their disease. Surgical management is the treatment of choice. We present a case of a patient that developed a tracheoesophageal fistula after tracheostomy. Surgical repair was done which failed due to infection. The patient was managed with the help of an esophageal stent and Trichloroacetic Acid cautery. This approach can be used in selected patients, depending upon the size and site of TEE Larger fistulae and those situated lower down e.g. supra carinal cannot be managed by this technique.  相似文献   
56.
57.
In last decade, dengue has emerged as one of the most important vector born disease. With increasing cases, uncommon presentations and complications are now commonly recognized. Here, we report two cases of rare pattern of respiratory involvement in dengue: acute respiratory distress syndrome and bronchiolitis with respiratory failure.  相似文献   
58.
59.
Gall bladder Carcinoma (GBC) is the fifth most common cancer of the digestive tract and frequently diagnosed in late stage of disease. Estimation of circulating free DNA (cfDNA) in serum has been applied as a “liquid biopsy” in several deep seated malignancies. Its value in diagnosis of gall bladder carcinoma has not been studied. The present study was designed to assess the role of cfDNA in the diagnosis of GBC and correlate levels with the TNM stage. Serum was collected from 34 patients with GBC and 39 age and sex matched controls including 22 cholecystitis and 17 healthy individuals. Serum cfDNA levels were measured through quantitative polymerase chain reaction (qPCR) by amplification of β-globin gene. Performance of the assay was calculated through the receiver operating characteristic (ROC) curve. The cfDNA level was significantly lower in healthy controls and cholecystitis (89.32 ± 59.76 ng/ml, 174.21 ± 99.93 ng/ml) compared to GBC (1245.91 ± 892.46 ng/ml, p = <0.001). The cfDNA level was significantly associated with TNM stage, lymph node involvement and jaundice (0.002, 0.027, and 0.041, respectively). Area under curve of ROC analysis for cancer group versus healthy and cholecystitis group was 1.00 and 0.983 with sensitivity of 100 %, 88.24 % and specificity of 100 % respectively. Quantitative analysis of cfDNA may distinguish cholecystitis and gall bladder carcinoma and may serve as new diagnostic, noninvasive marker adjunct to imaging for the diagnosis of GBC.  相似文献   
60.
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