全文获取类型
收费全文 | 815篇 |
免费 | 38篇 |
专业分类
853篇 |
出版年
2022年 | 9篇 |
2021年 | 16篇 |
2020年 | 9篇 |
2019年 | 9篇 |
2018年 | 17篇 |
2017年 | 15篇 |
2016年 | 12篇 |
2015年 | 28篇 |
2014年 | 35篇 |
2013年 | 44篇 |
2012年 | 66篇 |
2011年 | 56篇 |
2010年 | 35篇 |
2009年 | 22篇 |
2008年 | 44篇 |
2007年 | 50篇 |
2006年 | 39篇 |
2005年 | 42篇 |
2004年 | 38篇 |
2003年 | 30篇 |
2002年 | 36篇 |
2001年 | 21篇 |
2000年 | 13篇 |
1999年 | 7篇 |
1998年 | 5篇 |
1995年 | 6篇 |
1994年 | 5篇 |
1992年 | 5篇 |
1990年 | 9篇 |
1989年 | 8篇 |
1988年 | 5篇 |
1987年 | 6篇 |
1986年 | 5篇 |
1985年 | 5篇 |
1984年 | 7篇 |
1983年 | 4篇 |
1979年 | 6篇 |
1978年 | 5篇 |
1977年 | 7篇 |
1975年 | 5篇 |
1974年 | 3篇 |
1973年 | 4篇 |
1972年 | 6篇 |
1971年 | 5篇 |
1970年 | 5篇 |
1969年 | 4篇 |
1968年 | 8篇 |
1967年 | 5篇 |
1966年 | 6篇 |
1965年 | 3篇 |
排序方式: 共有853条查询结果,搜索用时 15 毫秒
21.
Gold salts and phenylbutazone selectively inhibit the synthesis of PGF2α and PGE2 respectively. Lowered production of one prostaglandin species is accompanied by an increased production of the other. Selective inhibition by these drugs was observed in the presence of adrenaline, reduced glutathione and copper sulphate under conditions when most anti-inflammatory compounds inhibited PGE2 and PGF2α syntheses equally. It is postulated that selective inhibitors may have a different mode of action
and beneficial effects may be related to the endogenous ratio of PGE to PGF required for normal function. 相似文献
22.
Rajská P Pechánová O Takác P Kazimírová M Roller L Vidlicka L Ciampor F Labuda M Nuttall PA 《Medical and veterinary entomology》2003,17(4):395-402
Salivary gland extract (SGE) of four horsefly species (Hybomitra bimaculata Macquart, Hybomitra ciureai Séguy, Tabanus bromius L., Tabanus glaucopis Meigen) and one deerfly species (Chrysops relictus Meigen) (Diptera: Tabanidae) were shown to contain vasodilatory activity. Aliquots equivalent to 1, 5 and 10 pairs of salivary glands (SG) relaxed rat femoral artery (with intact endothelium) pre-constricted with phenylephrine. Vasodilatory activity was dose-dependent. SGE of one horsefly species (Haematopota pluvialis L.) did not induce relaxation. The kinetics of vasodilation induced by SGE of four horsefly species differed from the deerfly. These results indicate that tabanid species may produce more than one type of vasodilator to aid blood feeding. 相似文献
23.
24.
A role for the deubiquitinating enzyme USP28 in control of the DNA-damage response 总被引:10,自引:0,他引:10
The Chk2-p53-PUMA pathway is a major regulator of DNA-damage-induced apoptosis in response to double-strand breaks in vivo. Through analysis of 53BP1 complexes we have discovered a new ubiquitin protease, USP28, which regulates this pathway. Using a human cell line that faithfully recapitulated the Chk2-p53-PUMA pathway, we show that USP28 is required to stabilize Chk2 and 53BP1 in response to DNA damage. In this cell line, both USP28 and Chk2 are required for DNA-damage-induced apoptosis, and they accomplish this in part through regulation of the p53 induction of proapoptotic genes like PUMA. Our studies implicate DNA-damage-induced ubiquitination and deubiquitination as a major regulator of the DNA-damage response for Chk2, 53BP1, and a number of other proteins in the DNA-damage checkpoint pathway, including several mediators, such as Mdc1, Claspin, and TopBP1. 相似文献
25.
In autoimmune (type 1) diabetes, autoreactive lymphocytes destroy pancreatic β-cells responsible for insulin synthesis. To
assess the feasibility of gene therapy for type 1 diabetes, recombinant vaccinia virus (rVV) vectors were constructed expressing
pancreatic islet autoantigens proinsulin (INS) and a 55-kDa immunogenic peptide from glutamic acid decarboxylase (GAD), and
the immunomodulatory cytokine interleukin (IL)-10. To augment the beneficial effects of recombinant virus therapy, the INS
and GAD genes were fused to the C terminus of the cholera toxin B subunit (CTB). Five-week-old non-obese diabetic (NOD) mice
were injected once with rVV. Humoral antibody immune responses and hyperglycemia in the infected mice were analyzed.
Only 20% of the mice inoculated with rVV expressing the CTB::INS fusion protein developed hyperglycemia, in comparison to
70% of the mice in the uninoculated animal group. Islets from pancreatic tissues isolated from euglycemic mice from this animal
group showed no sign of inflammatory lymphocyte invasion. Inoculation with rVV producing CTB::GAD or IL-10 was somewhat less
effective in reducing diabetes. Humoral antibody isotypes of hyperglycemic and euglycemic mice from all treated groups possessed
similar IgG1/IgG2c antibody titer ratios from 19 to 32 wk after virus inoculation. In comparison with uninoculated mice, 11-wk-old
NOD mice injected with virus expressing CTB::INS were delayed in diabetes onset by more than 4 wk. The experimental results
demonstrate the feasibility of using rVV expressing CTB::INS fusion protein to generate significant protection and therapy
against type 1 diabetes onset and progression. 相似文献
26.
27.
Byeong Tak Jeon Rok Won Heo Hyun Joo Shin Chin-ok Yi Yu Hee Lee Han-nah Joung 《Bioscience, biotechnology, and biochemistry》2013,77(3):482-489
A Vigna nakashimae (VN) extract has been shown to have antidiabetic and anti-obesity effects. However, the mechanism underlying the effect of a VN extract on hepatic inflammation and endoplasmic reticulum (ER) stress remains unclear. In the present study, we investigated how a VN extract protects against the development of non-alcoholic fatty liver disease (NAFLD). A VN extract for 12 weeks reduced the body weight, serum metabolic parameters, cytokines, and hepatic steatosis in high-fat diet (HFD)-fed mice. A VN extract decreased HFD-induced hepatic acetyl CoA carboxylase and glucose transporter 4 expressions. In addition to the levels of high-mobility group box 1 and receptor for advanced glycation, the hepatic expression of ATF4 and caspase-3 was also reduced by a VN extract. Thus, these data indicate that a chronic VN extract prevented NAFLD through multiple mechanisms, including inflammation, ER stress, and apoptosis in the liver. 相似文献
28.
29.
Man Lung Yeung Jade Lee Lee Teng Lilong Jia Chaoyu Zhang Chengxi Huang Jian-Piao Cai Runhong Zhou Kwok-Hung Chan Hanjun Zhao Lin Zhu Kam-Leung Siu Sin-Yee Fung Susan Yung Tak Mao Chan Kelvin Kai-Wang To Jasper Fuk-Woo Chan Zongwei Cai Susanna Kar Pui Lau Kwok-Yung Yuen 《Cell》2021,184(8):2212-2228.e12
30.
A ParaHox gene cluster is composed of three genes (Gsx, Xlox, and Cdx). It has been proposed that all three ParaHox genes were present in the last common ancestor to the lophotrochozoan protostomes and the deuterostomes and that gene loss event has occurred in the ecdysozoan lineage. In this paper, we report the existence of all three ParaHox genes in Perionyx excavatus, a clitellate annelid. Although orthologs of each of the three ParaHox genes were previously discovered from other lopotrochozoan taxa, this study constitutes the first reported isolation of all three ParaHox genes in the same clitellate species.Bum Joon Park and Sung-Jin Cho contributed equally to this work. 相似文献