全文获取类型
收费全文 | 587篇 |
免费 | 51篇 |
出版年
2023年 | 6篇 |
2022年 | 11篇 |
2021年 | 41篇 |
2020年 | 21篇 |
2019年 | 15篇 |
2018年 | 20篇 |
2017年 | 14篇 |
2016年 | 33篇 |
2015年 | 30篇 |
2014年 | 47篇 |
2013年 | 40篇 |
2012年 | 43篇 |
2011年 | 49篇 |
2010年 | 33篇 |
2009年 | 22篇 |
2008年 | 24篇 |
2007年 | 29篇 |
2006年 | 21篇 |
2005年 | 15篇 |
2004年 | 19篇 |
2003年 | 13篇 |
2002年 | 10篇 |
2001年 | 11篇 |
2000年 | 12篇 |
1999年 | 8篇 |
1998年 | 8篇 |
1997年 | 4篇 |
1996年 | 2篇 |
1995年 | 2篇 |
1994年 | 3篇 |
1993年 | 3篇 |
1992年 | 1篇 |
1991年 | 2篇 |
1990年 | 1篇 |
1989年 | 1篇 |
1988年 | 2篇 |
1987年 | 3篇 |
1986年 | 1篇 |
1985年 | 2篇 |
1984年 | 2篇 |
1983年 | 2篇 |
1982年 | 1篇 |
1981年 | 1篇 |
1980年 | 3篇 |
1977年 | 1篇 |
1974年 | 1篇 |
1972年 | 1篇 |
1967年 | 2篇 |
1966年 | 1篇 |
1965年 | 1篇 |
排序方式: 共有638条查询结果,搜索用时 843 毫秒
521.
Nyuji M Selvaraj S Kitano H Shiraishi T Yamaguchi A Shimizu A Matsuyama M 《Zoological science》2012,29(9):623-629
The gonadotropins (GtHs), follicle-stimulating hormone (FSH) and luteinizing hormone (LH), are heterodimers composed of a common α subunit (GPα) and a unique β subunit (FSHβ or LHβ); they are synthesized in and secreted from gonadotrophs (FSH and LH cells) in the pituitary. Little is known about the roles of FSH and LH during spermatogenesis in perciform fishes. In this study, we examined immunoreactive changes in FSH and LH cells, and changes in the gene expression of the three gonadotropin subunits in the pituitary of male chub mackerel Scomber japonicus during testicular development. FSHβ-immunoreactive (ir) and LHβ-ir cell area were measured immuno-histochemically based on the FSH and LH cell-occupying area in the proximal pars distalis. The FSHβ-ir cell area increased significantly during spermiation, while FSHβ mRNA levels, already high at the beginning of spermatogenesis, increased further, peaking during spermiation. In contrast, LHβ-ir cell area and LHβ mRNA levels, which were low at the beginning of spermatogenesis, increased significantly during late spermatogenesis, peaking during spermiation. For both FSH and LH, GtHβ-ir cell area and GtHβ mRNA levels decreased until gonadal resting. GPα mRNA levels showed similar changes to LHβ mRNA levels. These results suggest that in the chub mackerel, FSH may play an important role in the early and late phases of spermatogenesis, and that LH may play a role during late spermatogenesis and spermiation. Moreover, our results demonstrate that changes in GtHβ-ir cell area were accompanied by similar changes in the expression of the FSHβ and LHβ genes, both of which increased during testicular development. 相似文献
522.
One of the challenges faced by Mycobacterium tuberculosis (M. tuberculosis) in dormancy is hypoxia. DosR/DevR of M. tuberculosis is a two component dormancy survival response regulator which induces the expression of 48 genes. In this study, we have used DosR regulon proteins of M. tuberculosis H37Rv as the query set and performed a comprehensive homology search against the non-redundant database. Homologs were found in environmental mycobacteria, environmental bacteria and archaebacteria. Analysis of genomic context of DosR regulon revealed that they are distributed as nine blocks in the genome of M. tuberculosis with many transposases and integrases in their vicinity. Further, we classified DosR regulon proteins into eight functional categories. One of the hypothetical proteins Rv1998c could probably be a methylisocitrate lyase or a phosphonomutase. Another hypothetical protein, Rv0572 was found only in mycobacteria. Insights gained in this study can potentially aid in the development of novel therapeutic interventions. 相似文献
523.
524.
Bansal S Srinivasan S Anandasadagopan S Chowdhury AR Selvaraj V Kalyanaraman B Joseph J Avadhani NG 《The Journal of biological chemistry》2012,287(19):15284-15297
Alcohol treatment induces oxidative stress by a combination of increased production of partially reduced oxygen species and decreased cellular antioxidant pool, including GSH. Recently, we showed that mitochondrion-targeted CYP2E1 augments alcohol-mediated toxicity, causing an increase in reactive oxygen species production and oxidative stress. Here, we show that cytochrome c oxidase (CcO), the terminal oxidase of the mitochondrial respiratory chain, is a critical target of CYP2E1-mediated alcohol toxicity. COS-7 and Hep G2 cell lines expressing predominantly mitochondrion-targeted (Mt(++)) CYP2E1 and livers from alcohol-treated rats showed loss of CcO activity and increased protein carbonylation, which was accompanied by a decline in the steady state levels of subunits I, IVI1, and Vb of the CcO complex. This was also accompanied by reduced mitochondrial DNA content and reduced mitochondrial mRNA. These changes were more prominent in Mt(++) cells in comparison with wild type (WT) CYP2E1-expressing or ER(+) (mostly microsome-targeted) cells. In addition, mitochondrion-specific antioxidants, ubiquinol conjugated to triphenyl phosphonium, triphenylphosphonium conjugated carboxyl proxyl, and the CYP2E1 inhibitor diallyl sulfide prevented the loss of CcO activity and the CcO subunits, most likely through reduced oxidative damage to the enzyme complex. Our results suggest that damage to CcO and dissociation of respirosome complexes are critical factors in alcohol-induced toxicity, which is augmented by mitochondrion-targeted CYP2E1. We propose that CcO is one of the direct and immediate targets of alcohol-induced toxicity causing respiratory dysfunction. 相似文献
525.
526.
Vidya Ramachandran Muniyandi Malaisamy Manickam Ponnaiah Kanagasabai Kaliaperuaml Selvaraj Vadivoo Mohan Digambar Gupte 《PloS one》2012,7(12)
Background
Chikungunya Virus (CHIKV) infection affects large populations and leads to prolonged and debilitating pain affecting health related quality of life (HRQoL). We assess the impact of CHIKV on HRQoL of clinical CHIKV (C-CHIKV) patients in a suburban locality of Chennai City, South India. Further, we determined factors associated with clinical recovery among C-CHIKV patients.Methods
We followed-up 403 of 425 adult C-CHIKV cases identified during an outbreak. On the basis of a reassessment of their current clinical status through self-reporting, we categorized them as ‘clinically recovered’ (n = 308) or ‘not recovered’ (n = 95). In the absence of base-line information on HRQoL, we included a comparison group of healthy normal’s recruited by frequency matching for age and sex from the neighbourhood (n = 308). We conducted a comparative cross-sectional study of these three groups and estimated HRQoL scores using SF-36 questionnaire. We tested the differences in the median scores by Kruksall Wallistest. We identified factors associated with ‘recovery’ as compared to not-recovery by calculating Adjusted Odds Ratio (AOR) and 95% Confidence Intervals through multiple regression analysis.Results
As compared to ‘normals’, we observed a 20 and five-fold reductions in HRQoL scores for C-CHIKV patients ‘not recovered’ and ‘recovered’ respectively. Differences in HRQoL scores for all the domains were statistically significant between three groups (p<0·001). Younger age, male, absence of rashes, affliction of less than five types of joints and two weeks of joint swelling were significantly associated with recovery. HRQoL scores improved with time among those ‘clinically recovered’.Conclusion
This study provides evidence for sharp reductions in quality of life not only during active C-CHIKV associated illness but also for several months after clinical recovery compared to healthy normals. This has implications for developing intervention programmes in countries with high risk of CHIKV outbreaks. 相似文献527.
Sunil Kumar Tripathi Sanjeev Kumar Singh Poonam Singh Palanisamy Chellaperumal Karnati Konda Reddy Chandrabose Selvaraj 《Journal of molecular recognition : JMR》2012,25(10):504-512
Cyclin‐dependent kinases (CDKs) are core components of the cell cycle machinery that govern the transition between phases during cell cycle progression. Abnormalities in CDKs activity and regulation are common features of cancer, making CDK family members attractive targets for the development of anticancer drugs. Their inhibitors have entered in clinical trials to treat cancer. Very recently, Heathcote et al. (J. Med. Chem. 2010, 53:8508–8522) have found a ligand BS194 that has a high affinity with CDK2 (IC50 = 3 nm ) but shows low affinity with CDK1 (IC50 = 30 nm ). To understand the selectivity, we used homology modeling, molecular docking, molecular dynamics, and free‐energy calculation to analyze the interactions. A rational three‐dimensional model of the CDK1/BS194 complex is built. We found that Leu83 is a key residue that recognizes BS194 more effectively with CDK2 with good binding free energies rather than CDK1. Energetic analysis reveals that van der Waals interaction and non‐polar contributions to solvent are favorable in the formation of complexes and amine group of the ligand, which plays a crucial role for binding selectivity between CDK2 and CDK1. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
528.
Protection of Penaeus monodon against white spot syndrome virus by inactivated vaccine with herbal immunostimulants 总被引:1,自引:0,他引:1
Yogeeswaran A Velmurugan S Punitha SM Babu MM Selvaraj T Kumaran T Citarasu T 《Fish & shellfish immunology》2012,32(6):1058-1067
To improve the immune response in tiger shrimp Penaeus monodon against WSSV infection, juveniles (350 ± 10 mg) were vaccinated with formalin-inactivated WSSV and fed with herbal immunostimulants. The methanolic extracts of herbal immunostimulants such as Acalypha indica, Cynodon dactylon, Picrorrhiza kurrooa, Withania somnifera and Zingiber officinalis were incorporated in formulated diets at different concentrations; 250 (ED(1)), 500 (ED(2)), 1000 (ED(3)) and 2000 (ED(4)) mg kg(-1) of feed and fed for 60 days after vaccination. After 30 and 60 days intervals of feeding, the shrimps were challenged with WSSV, which were isolated and propagated from the infected crustaceans. The shrimps fed with control diets (C(1)) succumbed to death within 5 days after WSSV challenge, when no vaccination and immunostimulations were given. The other control groups (C(2) and C(3)) had slight improvements in all parameters including survival. The percentage survival was significantly (P < 0.05) increased to 30, 50 and 60% in the ED(2), ED(3) and ED(4) diets respectively after 60 days challenging. The better haematological, biochemical and immunological parameters were also found in the herbal extracts supplemented diets fed vaccinated shrimps. The present study revealed that the combined effect of immunostimulation and vaccination helped to boost the immune system against WSSV infection and hence this application can be adopted for shrimp culture. 相似文献
529.
530.
Devaraj Sasikala Kasivelu Govindaraju Selvaraj Tamilselvan Ganesan Singaravelu 《Biotechnology and Bioprocess Engineering》2012,17(6):1176-1181
The ethnopharmacological approach to the production of nanoparticles is directly related to the creation of an important symbiosis between nanoscience and medical science. Production of nanoparticles under ecofriendly conditions is of significance to address growing concerns on the overall toxicity of nanoparticles for medical and biotechnological applications. The present investigation demonstrates silver nanoparticles production capabilities of a miracle bean soybean Glycine max. We found that a single protein of soybean with a molecular weight of 51 kDa stabilizes the newly formed silver nanoparticles. The electroeluted protein has confirmed the bioreduction property of silver ions. 相似文献