全文获取类型
收费全文 | 696篇 |
免费 | 35篇 |
国内免费 | 2篇 |
专业分类
733篇 |
出版年
2023年 | 2篇 |
2022年 | 11篇 |
2021年 | 22篇 |
2020年 | 11篇 |
2019年 | 8篇 |
2018年 | 15篇 |
2017年 | 17篇 |
2016年 | 21篇 |
2015年 | 46篇 |
2014年 | 39篇 |
2013年 | 52篇 |
2012年 | 70篇 |
2011年 | 54篇 |
2010年 | 36篇 |
2009年 | 32篇 |
2008年 | 45篇 |
2007年 | 44篇 |
2006年 | 34篇 |
2005年 | 37篇 |
2004年 | 29篇 |
2003年 | 25篇 |
2002年 | 22篇 |
2001年 | 11篇 |
2000年 | 16篇 |
1999年 | 10篇 |
1998年 | 2篇 |
1997年 | 4篇 |
1996年 | 1篇 |
1995年 | 1篇 |
1994年 | 3篇 |
1993年 | 1篇 |
1992年 | 2篇 |
1989年 | 3篇 |
1988年 | 1篇 |
1987年 | 2篇 |
1986年 | 2篇 |
1984年 | 1篇 |
1961年 | 1篇 |
排序方式: 共有733条查询结果,搜索用时 15 毫秒
151.
Kim H Lee SJ Park JY Park YW Kim HS Kang HY Hur BK Ryu YW Han SI Kim JS 《Journal of microbiology (Seoul, Korea)》2004,42(1):25-31
Sf9 cells have obvious advantages for the conventional production technology of vaccine. They are useful tools for high concentration and large-scale cultures. Sf9 cells were grown to maximal concentration, 8 x 10(6) cells/ml in a 500ml spinner flask, with a doubling time at the exponentially growing phase of 24.5 hours, using serum-free media. To explore the ability of Sf9 cells to be infected by the Japanese encephalitis (JE) virus Beijing-1 strain, Sf9 cells were infected with the virus. By 4-5 days post-infection, 10-15% of the Sf9 cells showed cytopathic effect (CPE), from granularity to the formation of syncytia and multinucleated giant cells continuously observed over a period of 35 days. Positive fluorescent reactions were detected in 30-40% of cells infected with the JE virus Beijing-1 strain, and the uninfected Sf9 cells were completely negative. Virus particles, propagated in Sf9 and Vero cells, were concentrated by sedimentation on 40% trehalose cushions by ultracentrifugation, and showed identical patterns of viral morphogenesis. Complete virus particles, 40 to 50 nm in diameter, were observed, and JE virus envelope (E) proteins, at 53 kDa, were found in the western blot analysis to the anti-JE virus E protein monoclonal antibody and reacted as a magenta band in the same position to the glycoprotein staining. To evaluate whether the infectious virus was produced in Sf9 cells inoculated with the JE virus Beijing-1 stain, Sf9 cells were inoculated with the virus, and sample harvested every 5 days. The titers of the JE virus Beijing-1 strain rose from 1.0 x 10(5) to 1.5 x 10(6) pfu/ml. The infected Sf9 cells could be sub-cultured in serum-free medium, with no change in the plaque sizes formed by the JE virus Beijing-1 strain in the plaque assay. It is suggested that the ability of the JE virus Beijing-1 strain to infect Sf9 cells in serum-free media will provide a useful insect cell system, where the JE virus replication, cytopathogenicity and vaccine immunogen can be studied. 相似文献
152.
Young-Lai Cho Sung-Mo Hur Ji-Yoon Kim Ji-Hee Kim Dong-Keon Lee Jongeon Choe Moo-Ho Won Kwon-Soo Ha Dooil Jeoung Sanghwa Han Sungwoo Ryoo Hansoo Lee Jeong-Ki Min Young-Guen Kwon Dong-Hyun Kim Young-Myeong Kim 《The Journal of biological chemistry》2015,290(1):467-477
Ginsenoside Rg5 is a compound newly synthesized during the steaming process of ginseng; however, its biological activity has not been elucidated with regard to endothelial function. We found that Rg5 stimulated in vitro angiogenesis of human endothelial cells, consistent with increased neovascularization and blood perfusion in a mouse hind limb ischemia model. Rg5 also evoked vasorelaxation in aortic rings isolated from wild type and high cholesterol-fed ApoE−/− mice but not from endothelial nitric-oxide synthase (eNOS) knock-out mice. Angiogenic activity of Rg5 was highly associated with a specific increase in insulin-like growth factor-1 receptor (IGF-1R) phosphorylation and subsequent activation of multiple angiogenic signals, including ERK, FAK, Akt/eNOS/NO, and Gi-mediated phospholipase C/Ca2+/eNOS dimerization pathways. The vasodilative activity of Rg5 was mediated by the eNOS/NO/cGMP axis. IGF-1R knockdown suppressed Rg5-induced angiogenesis and vasorelaxation by inhibiting key angiogenic signaling and NO/cGMP pathways. In silico docking analysis showed that Rg5 bound with high affinity to IGF-1R at the same binding site of IGF. Rg5 blocked binding of IGF-1 to its receptor with an IC50 of ∼90 nmol/liter. However, Rg5 did not induce vascular inflammation and permeability. These data suggest that Rg5 plays a novel role as an IGF-1R agonist, promoting therapeutic angiogenesis and improving hypertension without adverse effects in the vasculature. 相似文献
153.
Wang Y Kim JA Cheong YH Joshi Y Koh YJ Hur JS 《Journal of microbiology (Seoul, Korea)》2011,49(3):473-480
The reducing polyketide synthases found in filamentous fungi are involved in the biosynthesis of many drugs and toxins. Lichens
produce bioactive polyketides, but the roles of reducing polyketide synthases in lichens remain to be clearly elucidated.
In this study, a reducing polyketide synthase gene (U1PKS3) was isolated and characterized from a cultured mycobiont of Usnea longissima. Complete sequence information regarding U1PKS3 (6,519 bp) was obtained by screening a fosmid genomic library. A U1PKS3 sequence
analysis suggested that it contains features of a reducing fungal type I polyketide synthase with β-ketoacyl synthase (KS),
acyltransferase (AT), dehydratase (DH), enoyl reductase (ER), ketoacyl reducatse (KR), and acyl carrier protein (ACP) domains.
This domain structure was similar to the structure of ccRadsl, which is known to be involved in resorcylic acid lactone biosynthesis
in Chaetomium chiversii. The results of phylogenetic analysis located U1PKS3 in the clade of reducing polyketide synthases. RT-PCR analysis results
demonstrated that UIPKS3 had six intervening introns and that UIPKS3 expression was upregulated by glucose, sorbitol, inositol, and mannitol. 相似文献
154.
155.
156.
157.
Pokeweed antiviral proteins (PAPs) become novel therapeutic agents in relation to application in human viral diseases and
cancer, as well as potent tools in plant system for defending viral infection. We have studied the expression characteristics
of PAPs in pokeweed plants by western blot analysis. PAP-I was constitutively expressed in leaves, stems and roots of the
pokeweed plant, while PAP-II was not expressed in roots. The expression of PAP-II began in May and then gradually increased
with development of the plants. The PAP-II expression was induced and/or stimulated not only by biotic stresses, such as insect
pests and viral infection, but also by abiotic stresses, like drought. Interestingly, low-light intensity was found to be
more effective than high-light in the expression of both PAP-I and PAP-II. Our results suggest that PAP-II appears to have
an additive effect in terms of protection of the plant against pathogens during summer-time when the plant actively grows
and is attacked by various pathogens. 相似文献
158.
159.
Jinlong Yin Gunwoo Park Tae Hoon Kim Jun Hee Hong Youn-Jae Kim Xiong Jin Sangjo Kang Ji-Eun Jung Jeong-Yub Kim Hyeongsun Yun Jeong Eun Lee Minkyung Kim Junho Chung Hyunggee Kim Ichiro Nakano Ho-Shin Gwak Heon Yoo Byong Chul Yoo Jong Heon Kim Eun-Mi Hur Jeongwu Lee Seung-Hoon Lee Myung-Jin Park Jong Bae Park 《PLoS biology》2016,14(1)
160.
Hae-Youn Lee Jinyoung Kim Wenying Quan June-Chul Lee Min-Soo Kim Seok-Hyung Kim 《Autophagy》2016,12(8):1390-1403
Autophagy, which is critical for the proper turnover of organelles such as endoplasmic reticulum and mitochondria, affects diverse aspects of metabolism, and its dysregulation has been incriminated in various metabolic disorders. However, the role of autophagy of myeloid cells in adipose tissue inflammation and type 2 diabetes has not been addressed. We produced mice with myeloid cell-specific deletion of Atg7 (autophagy-related 7), an essential autophagy gene (Atg7 conditional knockout [cKO] mice). While Atg7 cKO mice were metabolically indistinguishable from control mice, they developed diabetes when bred to ob/w mice (Atg7 cKO-ob/ob mice), accompanied by increases in the crown-like structure, inflammatory cytokine expression and inflammasome activation in adipose tissue. Mφs (macrophages) from Atg7 cKO mice showed significantly higher interleukin 1 β release and inflammasome activation in response to a palmitic acid plus lipopolysaccharide combination. Moreover, a decrease in the NAD+:NADH ratio and increase in intracellular ROS content after treatment with palmitic acid in combination with lipopolysaccharide were more pronounced in Mφs from Atg7 cKO mice, suggesting that mitochondrial dysfunction in autophagy-deficient Mφs leads to an increase in lipid-induced inflammasome and metabolic deterioration in Atg7 cKO-ob/ob mice. Atg7 cKO mice were more susceptible to experimental colitis, accompanied by increased colonic cytokine expression, T helper 1 skewing and systemic bacterial invasion. These results suggest that autophagy of Mφs is important for the control of inflammasome activation in response to metabolic or extrinsic stress, and autophagy deficiency in Mφs may contribute to the progression of metabolic syndrome associated with lipid injury and colitis. 相似文献