全文获取类型
收费全文 | 1658篇 |
免费 | 140篇 |
国内免费 | 43篇 |
专业分类
耳鼻咽喉 | 11篇 |
儿科学 | 37篇 |
妇产科学 | 25篇 |
基础医学 | 270篇 |
口腔科学 | 35篇 |
临床医学 | 203篇 |
内科学 | 393篇 |
皮肤病学 | 26篇 |
神经病学 | 124篇 |
特种医学 | 120篇 |
外科学 | 172篇 |
综合类 | 30篇 |
预防医学 | 126篇 |
眼科学 | 37篇 |
药学 | 120篇 |
中国医学 | 11篇 |
肿瘤学 | 101篇 |
出版年
2021年 | 21篇 |
2020年 | 16篇 |
2019年 | 15篇 |
2018年 | 28篇 |
2017年 | 18篇 |
2016年 | 27篇 |
2015年 | 45篇 |
2014年 | 40篇 |
2013年 | 50篇 |
2012年 | 64篇 |
2011年 | 62篇 |
2010年 | 44篇 |
2009年 | 45篇 |
2008年 | 47篇 |
2007年 | 89篇 |
2006年 | 40篇 |
2005年 | 65篇 |
2004年 | 57篇 |
2003年 | 48篇 |
2002年 | 57篇 |
2001年 | 42篇 |
2000年 | 47篇 |
1999年 | 45篇 |
1998年 | 45篇 |
1997年 | 35篇 |
1996年 | 29篇 |
1995年 | 24篇 |
1994年 | 29篇 |
1993年 | 26篇 |
1992年 | 35篇 |
1991年 | 31篇 |
1990年 | 35篇 |
1989年 | 29篇 |
1988年 | 38篇 |
1987年 | 34篇 |
1986年 | 39篇 |
1985年 | 31篇 |
1984年 | 21篇 |
1983年 | 29篇 |
1982年 | 15篇 |
1980年 | 19篇 |
1979年 | 20篇 |
1978年 | 22篇 |
1977年 | 11篇 |
1976年 | 14篇 |
1975年 | 17篇 |
1971年 | 12篇 |
1970年 | 11篇 |
1969年 | 13篇 |
1840年 | 13篇 |
排序方式: 共有1841条查询结果,搜索用时 31 毫秒
1.
2.
3.
Xian ZH Zhang SH Cong WM Wu WQ Wu MC 《第二军医大学学报》2005,26(11):1320-1320
BACKGROUND: Hepatocellular carcinoma (HCC) is one of the most prevalent fatal cancers in the world. Despite advances in early diagnosis and improvements in surgical techniques, the survival of patients with HCC even after resection is poor because of the high incidence of recurrences. Therefore, the identification of prognostic factors may be helpful in the development of new treatment protocols. AIMS: To investigate HER-2/neu status in HCC by immunohistochemistry (IHC) and fluorescence in situ hybridisation (FISH), and to explore the possibility of using trastuzumab in the treatment of HCC. METH ODS: Eight hundred and sixty eight surgical samples from patients with primary HCC were examined for their HER-2/neu status. IHC for HER-2/neu was performed with the HercepTest kit; FISH analysis was performed with the PathVysion HER-2 DNA probe kit. The correlations between HER-2/neu overexpression and clinicopathological characteristics were analysed statistically. RESULTS: HER-2/neu overexpression was detected in 21 (2.42%) of the 868 primary HCCs. Only one specimen showed HER-2/neu gene amplification by FISH. No significant associations were found between HER-2/neu overexpression and the clinicopathological parameters. CONCLUSIONS: There is a low frequency of HER-2/neu overexpression/amplification in HCC. There appears to be no role for HER-2/neu as a prognostic marker and no benefit of anti-HER-2/neu trastuzumab treatment in patients with HCC. 相似文献
4.
Questionable data and preconceptions: reconsidering the value of mammography for American Indian Women. 总被引:3,自引:1,他引:2
下载免费PDF全文
![点击此处可从《American journal of public health》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Although the benefits of mammography are well established, many remain skeptical of the value of mammography for American Indian women. This skepticism stems in part from a belief that breast cancer is too rare an event among American Indians to warrant widespread screening. The validity of this assumption for Northern Plains Indians is challenged by a discussion of the limitations of available data on breast cancer in American Indian populations (including lack of generalizability, underestimation, and an overreliance on relative rather than absolute measures of cancer incidence) and by findings from the Minnesota Breast and Cervical Cancer Control Program, a federally funded program providing free breast and cervical cancer screening to American Indian and other women in Minnesota. In light of this information, the authors recommend that the low priority of mammography for American Indian women be reconsidered. 相似文献
5.
This study investigated the relationship between increased serotonin (5-hydroxytryptamine, 5HT) receptor sensitivity and human aggression. A low oral dose of meta-chlorophenylpiperazine (MCPP), a postsynaptic 5HT receptor agonist, was administered in a placebo-controlled design to depressed (n = 22) and panic disorder (n = 20) patients classified with or without signs of outwardly directed aggression, patients with a history of suicide attempts (inwardly directed aggression) (n = 11), and normal controls (n = 19). Hormones under 5HT control were measured at 30-min intervals. Results were as follows: (1) MCPP did not induce or reduce anger, (2) patients with outwardly directed aggression did not have significantly greater MCPP-induced cortisol or prolactin release than did patients without signs of outwardly directed aggression, (3) patients with a history of suicide attempts did not have significantly greater MCPP-induced cortisol or prolactin release than did normal controls, and (4) MCPP-induced hormone release was unrelated to measures of aggression. 相似文献
6.
A Gossler T Doetschman R Korn E Serfling R Kemler 《Proceedings of the National Academy of Sciences of the United States of America》1986,83(23):9065-9069
This study demonstrates that blastocyst-derived embryonic stem cells (ES cells) can be used as a vehicle for transgenesis. The method is nearly as efficient as other methods, and the introduced neomycin phosphotransferase (neo) gene is stably transmitted through several generations with no apparent loss in G418 resistance. An important factor contributing to the efficiency of this process is the rigorous selection, before blastocyst injection, of genetically transformed cells for in vitro developmental pluripotency. One of the advantages of the ES cell route to transgenesis is that it provides investigators with the opportunity to screen for the desired genetic alterations before reintroducing the ES cells into the animal. 相似文献
7.
8.
中西医结合医院单病种的质量管理及其作用 总被引:1,自引:0,他引:1
针对中西医结合医院单病种质量评定没有现成的、规范的标准的现状,就中西医结合单病种的质量管理方法及其在中西医结合医院建设中的作用进行了论述。 相似文献
9.
10.
Nordihydroguaiaretic acid inhibits voltage-activated Ca2+ currents independently of lipoxygenase inhibition 总被引:7,自引:0,他引:7
The effects of nordihydroguaiaretic acid (NDGA), a widely used lipoxygenase inhibitor, were examined on voltage-activated Ca2+ channel currents in GH3 and AtT-20 pituitary cells. NDGA (10-100 microM) produced a reversible, dose-dependent inhibition of Ca2+ channel currents, with half-maximal inhibition occurring at 18.6 microM. Inhibition by NDGA developed relatively slowly, did not exhibit use dependence or voltage dependence, and did not require access of NDGA to the extracellular domain of the Ca2+ channel. The maximum inhibition of macroscopic currents by 30 microM NDGA was equivalent in the presence of 5 and 50 mM extracellular Ca2+ and 5 mM Ba2+. NDGA inhibited Ca2+ channel currents in excised, outside-out patches, in the absence of intra- and extracellular Ca2+ (with Ba2+ as the charge carrier), and following preincubation of the cells with the phospholipase A2 inhibitor 4-bromophenacylbromide. Of five other lipoxygenase inhibitors tested, only one inhibited Ca2+ currents. These results suggest that NDGA inhibits Ca2+ channel currents by a mechanism distinct from that of other known Ca2+ channel antagonists and that, when influx of Ca2+ through voltage-gated channels is involved, inhibition of Ca2(+)-dependent cell functions by NDGA (greater than 10 microM) may be independent of effects on arachidonic acid metabolism. 相似文献