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   8332篇
  免费   421篇
  国内免费   55篇
耳鼻咽喉   173篇
儿科学   145篇
妇产科学   127篇
基础医学   976篇
口腔科学   296篇
临床医学   489篇
内科学   2031篇
皮肤病学   207篇
神经病学   749篇
特种医学   220篇
外科学   1199篇
综合类   52篇
一般理论   1篇
预防医学   240篇
眼科学   157篇
药学   616篇
中国医学   18篇
肿瘤学   1112篇
  2023年   45篇
  2022年   86篇
  2021年   148篇
  2020年   80篇
  2019年   103篇
  2018年   179篇
  2017年   121篇
  2016年   154篇
  2015年   155篇
  2014年   192篇
  2013年   242篇
  2012年   376篇
  2011年   390篇
  2010年   241篇
  2009年   175篇
  2008年   355篇
  2007年   430篇
  2006年   445篇
  2005年   461篇
  2004年   418篇
  2003年   395篇
  2002年   361篇
  2001年   304篇
  2000年   262篇
  1999年   242篇
  1998年   126篇
  1997年   78篇
  1996年   76篇
  1995年   79篇
  1994年   70篇
  1993年   65篇
  1992年   185篇
  1991年   153篇
  1990年   179篇
  1989年   146篇
  1988年   141篇
  1987年   158篇
  1986年   121篇
  1985年   139篇
  1984年   97篇
  1983年   77篇
  1982年   37篇
  1980年   37篇
  1979年   63篇
  1978年   39篇
  1977年   35篇
  1975年   32篇
  1974年   39篇
  1972年   33篇
  1971年   30篇
排序方式: 共有8808条查询结果,搜索用时 15 毫秒
1.
A new macrolide antibiotic, clarithromycin (TE-031, A-56268), was studied for its clinical efficacy in the field of pediatrics. Patients treated were infants and children ranging from 2 months to 11 years old suffering from acute bronchitis in 5 cases, acute tonsillitis in 2 cases, Mycoplasma pneumonia in 2 cases, pertussis in 6 cases, scarlatina in 1 case and acute enteritis in 2 cases, a total of 18 cases. TE-031 was administered 19.7-43.5 mg/kg in daily doses and lengths of treatment ranged from 4 to 19 days. As regards to its clinical efficacy, good or excellent results were obtained in all cases: excellent in 11 cases and good in 7 cases. No clinical side effects nor abnormal laboratory test values obviously attributable to TE-031 were observed.  相似文献   
2.
3.
4.
Dehydrochlorinated poly(vinylidene chloride) proved to be a conjugated polyene-polyene polymer. Shock compression of the polymer formed a large portion of graphite and trace amounts of diamond and of an unknown carbon. The unknown carbon belongs to the hexagonal crystal system and possesses the cell dimension α0 = 0.338 nm. A comparison with known carbynes was made in terms of the crystalline parameters.  相似文献   
5.
6.
The only workers presently exposed to bagasse dust in Japan are the employees of sugar refineries and lacquerware factories. A follow up study of six former cases of bagassosis from among the retired employees of a paper board factory, closed since 1973, showed that none of the subjects still had bagassosis. Examinations of 70 employees of a sugar refinery for allergic reactions also showed no case of bagassosis. Seven cases with suspicious shadows of bagassosis on chest radiographs and four cases with positive serum precipitin to stored bagasse were, however, found among those 70 subjects. The results show the disappearance of a past episode of bagassosis and the possibility of a new occurrence of bagassosis among the employees of sugar refineries and lacquerware factories in the near future in Japan.  相似文献   
7.
S Nomura  G Osawa  M Karai 《Nephron》1990,55(2):210-213
A 41-year-old hemodialyzed woman developed ascites and was found to have secondary iron overload. The dose of administered iron was approximately 11-12 g, and her serum ferritin level was 15,000 ng/ml (15,000 micrograms/l). There were no signs of congestive heart failure, fluid overload, or liver cirrhosis. A program of weekly phlebotomy combined with recombinant human erythropoietin (rhEPO) therapy was tried to eliminate the iron congestion. After 9 months of this therapy, about 5 g of iron had been removed. The ascites completely disappeared, and her serum ferritin level fell to 5,800 ng/ml (5,800 micrograms/l). This suggests that such combined therapy would be useful when iron overload must be corrected rapidly. Before therapy, the sterile ascitic fluid showed exudative characteristics with 3.7 g/dl (37 g/l) of total protein. The serum-ascites albumin difference was 0.6 g/dl (6 g/l), and the fluid contained 1,400 inflammatory cells/mm3 (1.4 X 10(9)/l). Notably, the serum-ascites albumin difference increased in parallel with iron elimination. These findings suggested that iron deposition may have played a role in changing the permeability of the peritoneum, or in impairing lymphatic drainage, both of which are presumed to be pathogenetic factors of nephrogenic ascites.  相似文献   
8.
9.
The association of replacement estrogens with breast cancer   总被引:4,自引:0,他引:4  
This epidemiologic case-control study examined the relationship between replacement estrogen use and breast cancer risk in 2 population groups in Hawaii. No significant associations were observed when 161 Caucasian cases were compared with either their neighborhood controls (RR = 0.9; 95% Cl = 0.5-1.3) or their hospital controls (RR = 0.7; 95% Cl = 0.4 to 1.1) and when 183 Japanese cases were compared with either their neighborhood controls (RR = 1.1; 95% Cl = 0.7-1.6) or their hospital controls (RR = 1.0; 95% Cl = 0.6-1.4). The results indicate that the use of replacement estrogens cannot account for the large difference in breast cancer incidence between the 2 Hawaiian ethnic groups. However, further data analysis involving neighborhood controls was suggestive of a possible increase in breast cancer risk with estrogen use for certain sub-groups of women who are at high risk for the disease. These included estrogen users with a family history of breast cancer or a history of benign breast disease. These findings are in agreement with other studies which have used non-hospitalized controls. Because the numbers of cases in this study are not substantial, it is recommended that a large population-based case-control study be undertaken to clarify the relationship between breast cancer risk and replacement estrogen use, especially in sub-groups of women at high risk for the disease.  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