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   49873篇
  免费   4274篇
  国内免费   2382篇
耳鼻咽喉   480篇
儿科学   706篇
妇产科学   757篇
基础医学   6959篇
口腔科学   1142篇
临床医学   4970篇
内科学   9078篇
皮肤病学   773篇
神经病学   3575篇
特种医学   1859篇
外国民族医学   13篇
外科学   6137篇
综合类   5495篇
一般理论   10篇
预防医学   2931篇
眼科学   1230篇
药学   4887篇
  15篇
中国医学   1350篇
肿瘤学   4162篇
  2023年   418篇
  2022年   966篇
  2021年   1376篇
  2020年   921篇
  2019年   1033篇
  2018年   1368篇
  2017年   1092篇
  2016年   1122篇
  2015年   1455篇
  2014年   1810篇
  2013年   1857篇
  2012年   2717篇
  2011年   2844篇
  2010年   1701篇
  2009年   1432篇
  2008年   2246篇
  2007年   2307篇
  2006年   2157篇
  2005年   1956篇
  2004年   1538篇
  2003年   1414篇
  2002年   1209篇
  2001年   2722篇
  2000年   2685篇
  1999年   2254篇
  1998年   1010篇
  1997年   753篇
  1996年   585篇
  1995年   534篇
  1994年   408篇
  1993年   347篇
  1992年   1162篇
  1991年   1044篇
  1990年   920篇
  1989年   992篇
  1988年   896篇
  1987年   825篇
  1986年   779篇
  1985年   660篇
  1984年   410篇
  1983年   339篇
  1982年   189篇
  1981年   155篇
  1980年   126篇
  1979年   206篇
  1978年   90篇
  1974年   85篇
  1973年   93篇
  1972年   93篇
  1971年   94篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
51.
High-dose methotrexate (MTX) toxicity is reduced by a non-toxic dose of 5-fluorouracil (FU) when these agents are used in combination. Changes in the hematopoietic system (platelets, erythrocytes, leukocytes, hemoglobin, and hematocrit), ileal tissue, body weight, and mean survival were used as parameters to assess toxicity. For all parameters studied, there were no significant differences between the scheduling of MTX (245 mg/kg) after a priming dose of FU (25 mg/kg), simultaneous MTX and FU, FU alone, and control. However, sequential treatment with MTX followed by FU, and MTX alone resulted in: a marked decrease in the hematopoietic parameters; significant morphological changes in ileal tissue; a reduction of body weight; and increased mortality of animals. Hence, this study suggests that FU, a cytotoxic agent, may protect against MTX toxicity and improve its therapeutic index when FU administration precedes MTX or when these agents are given simultaneously.  相似文献   
52.
53.
54.
55.
56.
57.
现察口腔修复临床电刀龈成形术的效果。方法:对81例口腔修复门诊牙体缺损患者用电刀进行牙龈成形术并定期复诊观察。结果:81例术后牙龈全部达到修复要求而立即修复,其中70例术后牙龈稳定,占总数的86.4%。结论:电刀龈成形术是口腔修复临床上一种可行的治疗手段。  相似文献   
58.
59.
Q Chen  P Sun  I Prigione  H Xie  S Ferrini 《Tumori》1992,78(2):79-86
In an attempt to construct bispecific monoclonal antibodies (bimAbs) able to target cytotoxic T lymphocytes against human hepatoma cells, an HGPRT-deficient mutant of the Hepama-6 hybridoma, which produces an antihuman-hepatoma mAb, was directly fused with splenocytes from Balb/C mice immunized by a polyclonal cytotoxic T-cell line. Hybrid hybridomas were selected in HAT medium, and their supernatants were directly screened for the ability to induce IL-2-cultured cytotoxic T lymphocytes to kill hepatoma cells in a 51Cr-release assay. The selected hybrid hybridoma, termed DQ-33, secretes a bimAb, which reacts with a CD3-associated determinant. When resting peripheral-blood lymphocytes were used as effector cells, virtually no cytolytic activity could be induced by DQ-33, whereas phytohemagglutinin-activated lymphocytes that had been expanded in vitro in IL-2-containing medium could be efficiently targeted against hepatoma cells. Targeting by DQ-33 bimAb was analyzed on different subsets of IL-2-cultured lymphocytes. It was evident that CD+4-8+ TCR alpha/beta+ and CD3+4-8-TCR gamma/delta+ lymphocytes were efficiently induced by bimAb to lyse human hepatoma cells, whereas no induction of cytolysis could be observed when CD3 + 4 + 8-TCR alpha/beta+ cells were used as effectors. DQ-33 bimAb was also able to induce lymphokine secretion (IL-2, GM-CSF and TNF-alpha) by all the different subsets of lymphocytes analyzed in the presence of target cells expressing the relevant antigen, independent of the expression of cytolytic activity.  相似文献   
60.
C Q Wang  H Q Xu  Z P Luo 《中华内科杂志》1992,30(10):643-5, 660
61 patients with cerebellar hemorrhage were studied. The age at onset ranged from 15 to 84 years with a mean of 57.4 years. 49 cases were treated conservatively and 12 surgically and the mortality rates of the two groups were 32.5% and 25% respectively. Based on this study, it is suggested that the clinical and CT indications of surgical treatment of hematoma are as follows; Severe disturbance of consciousness; Bilateral eyeball fixation; Volume of hematoma over 10 ml; Size of hematoma over 4 cm in diameter; Marked acute obstructive hydrocephalus; Compression of cisterna ambieus and quadrigeminus.  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