全文获取类型
收费全文 | 494篇 |
免费 | 29篇 |
国内免费 | 31篇 |
专业分类
耳鼻咽喉 | 2篇 |
儿科学 | 14篇 |
妇产科学 | 3篇 |
基础医学 | 67篇 |
口腔科学 | 3篇 |
临床医学 | 44篇 |
内科学 | 66篇 |
皮肤病学 | 5篇 |
神经病学 | 31篇 |
特种医学 | 75篇 |
外科学 | 46篇 |
综合类 | 20篇 |
一般理论 | 1篇 |
预防医学 | 40篇 |
眼科学 | 8篇 |
药学 | 37篇 |
肿瘤学 | 92篇 |
出版年
2022年 | 3篇 |
2021年 | 4篇 |
2020年 | 3篇 |
2018年 | 5篇 |
2015年 | 9篇 |
2014年 | 8篇 |
2013年 | 14篇 |
2012年 | 14篇 |
2011年 | 10篇 |
2010年 | 4篇 |
2009年 | 7篇 |
2008年 | 12篇 |
2007年 | 16篇 |
2006年 | 17篇 |
2005年 | 22篇 |
2004年 | 8篇 |
2003年 | 14篇 |
2002年 | 14篇 |
2001年 | 25篇 |
2000年 | 23篇 |
1999年 | 21篇 |
1998年 | 15篇 |
1997年 | 11篇 |
1996年 | 11篇 |
1995年 | 11篇 |
1994年 | 14篇 |
1993年 | 8篇 |
1992年 | 10篇 |
1991年 | 20篇 |
1990年 | 16篇 |
1989年 | 19篇 |
1988年 | 14篇 |
1987年 | 13篇 |
1986年 | 13篇 |
1985年 | 15篇 |
1984年 | 12篇 |
1983年 | 7篇 |
1982年 | 8篇 |
1981年 | 5篇 |
1980年 | 3篇 |
1979年 | 4篇 |
1977年 | 5篇 |
1976年 | 7篇 |
1975年 | 7篇 |
1974年 | 7篇 |
1973年 | 9篇 |
1972年 | 4篇 |
1969年 | 4篇 |
1968年 | 5篇 |
1967年 | 6篇 |
排序方式: 共有554条查询结果,搜索用时 15 毫秒
1.
P M Doraiswamy K R Krishnan O B Boyko M M Husain G S Figiel V J Palese P R Escalona S A Shah W M McDonald W J Rockwell 《Progress in neuro-psychopharmacology & biological psychiatry》1991,15(3):351-356
1. The frequent occurrence of hypothalamo-pituitary dysfunction in patients with eating disorders as well as prior reports that nutritional and endocrine status influence pituitary morphology, led us to hypothesize that pituitary size and shape may be altered in patients with eating disorders. 2. Magnetic resonance imaging (MRI) does not use ionizing radiation and is currently one of the most feasible modalities available to study the pituitary gland in vivo. Using MRI, we have previously reported in a preliminary study that female patients with eating disorders had significantly smaller pituitary glands than controls. In addition MRI excluded any pituitary mass lesions. 3. In this report, we confirm our previous MRI findings and provide further evidence of pituitary abnormalities in an expanded sample of eating disorder patients. Preliminary data on pituitary volume estimates from MRI scans are provided for a subset of patients and controls. 相似文献
2.
7-甲氧基-4′-羟基-3′-二乙胺甲基异黄酮(MHDF)对大鼠血流动力学和主动脉的作用 总被引:2,自引:0,他引:2
本实验观察了MHDF对整体大鼠血流动力学和离体大鼠胸主动脉的作用。结果表明iv MHDF(3~12.8 mg/kg)能降低大鼠左心室±dp/dtmax,Vmax,Vpm和LVSP,延长T-dp/dtmax,减慢心率。MHDF还能舒张大鼠胸主动脉,ED50为6.5×10-6mol/L;非竞争拮抗NA和CaCl2致主脉收缩,pD2′为3.11±0.21和3.73±0.07;抑制高K+致主动脉收缩,IC50为1.76×10-5mol/L。提示MHDF对血管的作用与α受体阻断剂不同,而可能与钙拮抗有关。 相似文献
3.
4.
5.
6.
S Rockwell 《Cancer research》1985,45(4):1601-1607
The growth of colonies in semisolid medium is receiving widespread attention as a possible test for predicting the clinical response of individual human tumors to specific drugs. One problem encountered in these studies is the difficulty of preparing single-cell suspensions from solid tumors. Often, microscopic examination of the cultures just after plating reveals many clusters or clumps of cells; these are often large enough and numerous enough that some plates are counted or fixed immediately so that this "background" can be subtracted from the "colony" count used to assess cell viability. However, this correction addresses only one of the problems created by the presence of clumps and clusters. It does not eliminate errors and artifacts introduced by multiplicity (multiple clonogenic cells contributing to a colony), abortive clones, and cell volume changes, or by inhomogeneities in the microenvironment, cell metabolism, and drug distribution within clumps. Because of such factors, survival curves determined using suspensions contaminated with clumps and clusters may provide inaccurate assessments of the true drug sensitivity of the individual tumor cells. 相似文献
7.
8.
心脏直视手术围术期自体血回输335例的监护 总被引:2,自引:0,他引:2
0 引言 自体输血是采集患者体内血或回收自体失血,再输回同一患者,献血者与受血者为同一个体,既可以节约临床用血,减少患者费用,更重要是可以避免或减少同种输血传播感染性疾病.我科对335例体外循环心内直视手术患者实行自体血回输,收到较好的社会效益和经济效益.1 临床资料 1998-09/1999-02,我科心脏直视手术共445例,围术期采用自体输血335例,其中先心病226例,瓣膜手术59例,复杂心内畸形37例,冠心病、大血管13例,占同期体外循环心内直视手术75%.患者主要适应证:心脏及大血管外科手术,术前一般情况尚好,无肝、肾、呼吸功能障碍;术前检查… 相似文献
9.
Shyam K Penketh PG Shapiro M Belcourt MF Loomis RH Rockwell S Sartorelli AC 《Journal of medicinal chemistry》1999,42(5):941-946
Some 4- and 2-(nitrobenzyloxycarbonyl)-1, 2-bis(methylsulfonyl)-1-(2-chloroethyl)hydrazines (4, 6, and 7) were synthesized and evaluated for their ability to exert preferential toxicity to hypoxic EMT6 mammary carcinoma cells using a colony-forming assay. Of these, the 4,5-dimethoxy-2-nitro analogue 6 (50 microM, 1-h exposure) caused greater than 3 logs of kill of hypoxic cells, with relatively minor toxicity to corresponding aerobic cells. The ability of 4-nitro (4) and 4,5-dimethoxy-2-nitro (6) analogues to reach and kill hypoxic cells of solid tumors was also demonstrated using intradermally implanted EMT6 solid tumors in mice. In addition, a possible source of toxicity to normal tissue, i. e., the activation of the 4-nitrobenzyl derivative 4 by glutathione S-transferase-catalyzed thiolysis, was essentially eliminated by replacing one of the benzylic methylene protons by a methyl group. The 4-nitro (4) and 4,5-dimethoxy-2-nitro (6) analogues also appear to be reduced more easily under acidic conditions (pH 6.0) than under neutral conditions, as measured by differential pulse polarography. Since the pH in hypoxic regions is often lower than that in adjacent aerobic regions, this property should aid in the cytotoxic action of these agents against hypoxic cells of solid tumors. 相似文献
10.