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:      
  示例: 沙坡头地区,人工植被区,变化  检索词用空格隔开表示必须包含全部检索词,用“,”隔开表示只需满足任一检索词即可!
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   1360244篇
  免费   77692篇
  国内免费   1571篇
耳鼻咽喉   19789篇
儿科学   40449篇
妇产科学   38683篇
基础医学   188623篇
口腔科学   39901篇
临床医学   113043篇
内科学   263830篇
皮肤病学   30289篇
神经病学   106982篇
特种医学   53860篇
外国民族医学   435篇
外科学   208816篇
综合类   31158篇
现状与发展   6篇
一般理论   437篇
预防医学   92292篇
眼科学   31674篇
药学   100267篇
  22篇
中国医学   2993篇
肿瘤学   75958篇
  2018年   11819篇
  2016年   10845篇
  2015年   12098篇
  2014年   16917篇
  2013年   25426篇
  2012年   33142篇
  2011年   35021篇
  2010年   20846篇
  2009年   20361篇
  2008年   33662篇
  2007年   36805篇
  2006年   37338篇
  2005年   36110篇
  2004年   35163篇
  2003年   34107篇
  2002年   33657篇
  2001年   63686篇
  2000年   65387篇
  1999年   55414篇
  1998年   14665篇
  1997年   13484篇
  1996年   12958篇
  1995年   12239篇
  1994年   11480篇
  1992年   42782篇
  1991年   41304篇
  1990年   40574篇
  1989年   39567篇
  1988年   36981篇
  1987年   36437篇
  1986年   34920篇
  1985年   33128篇
  1984年   24838篇
  1983年   21063篇
  1982年   12681篇
  1981年   11584篇
  1979年   23941篇
  1978年   17085篇
  1977年   14841篇
  1976年   13401篇
  1975年   15281篇
  1974年   18084篇
  1973年   17562篇
  1972年   16815篇
  1971年   15719篇
  1970年   14914篇
  1969年   14349篇
  1968年   13462篇
  1967年   12018篇
  1966年   11259篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
61.
62.
63.
Internal eye wall resection in the management of uveal melanoma   总被引:3,自引:0,他引:3  
Twenty patients with presumed uveal melanoma underwent internal eye wall resection. It was the primary procedure in 13 patients who had tumours within 2 disc diameters of the optic nerve head and was combined with external resection in the remainder. Malignant melanoma was confirmed histologically in 15 patients; the diagnosis was a benign tumour in the other 5. The length of follow-up ranged from 2 to 37 (mean 19) months. In all cases the retina was completely attached at the time of last examination. The visual acuity ranged from 20/40 to hand movements; nine patients had an acuity of 20/400 or better. At the time of writing no metastatic disease or local recurrence had developed in any of the 15 patients in whom malignant melanoma was diagnosed.  相似文献   
64.
65.
66.
A prognosis of patients with a curative resected advanced cancer of the lower gastric region was worse than that of the other region of the stomach. The 5 year survival rate was only 47.3%. One of the main reasons was that a rate of lymph node recurrence was higher. In this point of view, we studied on lymphatic flow of the lower gastric region using an activated carbon particle (CH40). Lymph nodes were stained black soon after the injection of CH40 into the lower gastric wall at laparotomy. The black stained rate of an each regional lymph node was as follows. 3. 58%, 4. 17%, 5. 50%, 6. 25%, 1. 21%, 7. 58%, 8. 83%, 9. 58%, 11. 17% and 12. 33% in case of injection into the greater curvature and and 4. 31%, 6. 100%, 8. 25%, 9. 25%, 14V and 56% in case of injection into the lesser curvature. The stained rate was relatively high in 12 and 14V lymph node which we had not routinely dissected. The rates of lymph nodes stained black were related to those of cancer metastasis. The results suggest that lymphadenectomy of 12 for the cancer at the lesser curvature and that of 14V for the cancer at the greater curvature might make a prognosis of lower gastric cancer better.  相似文献   
67.
68.
During recent decades there has been a controversial discussion if comparable plasma level profiles which are rather constant or those which show a high peak are more efficient for the cure of gonorrhoea. So far, investigations in this field were not based on the Grasso apparatus. Although the findings with cefotiam and ceftizoxime do not allow to formulate a general hypothesis without any restriction, it can be stated that on the basis of an identical area under the antibiotic level time curve, 'peak concentration' profiles are more favourable.  相似文献   
69.
In the search for explanation of persistent cognitive impairmentassociated with alcohol dependence, the possible role of liverdisease has aroused considerable interest. However, review ofthe relevant literature provides only ambiguous support forany general relationship between neuropsycho-logical statusand laboratory tests of liver function. We tested the generalhypothesis, and also two specific hypotheses relating particularliver function parameters (  相似文献   
70.
The results of the in vitro fertilisation programme at Tygerberg Hospital for the period April 1983 to January 1988 are presented. Of the 1117 laparoscopies performed, 825 patients reached the transfer stage. A live-birth rate of 9.3% was achieved. The pregnancy rate after transfer of 4 embryos was 25.9% compared with 15.4% after 2 embryos and 10.8% after 3 embryos (P = less than 0.0001). The multiple pregnancy rate was 2.8% in the group receiving 2 embryos and 11.7% and 10.4% in those receiving 3 and 4 embryos, respectively. Of the 77 successful pregnancies (90 babies), 1 baby died at 34 weeks' gestation as the result of abruptio placentae due to preeclampsia and 1 cot death occurred. The only congenital abnormality encountered was a cleft palate.  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