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排序方式: 共有245条查询结果,搜索用时 15 毫秒
1.
Kelly D Sullivan Vignesh V Palaniappan Joaquín M Espinosa 《Cell cycle (Georgetown, Tex.)》2015,14(1):56-63
Despite extensive study, the mechanisms of cell fate choice upon p53 activation remain poorly understood. Using genome-wide shRNA screening, we recently identified the ATM kinase as synthetic lethal with Nutlin-3, an MDM2 inhibitor that leads to non-genotoxic p53 activation. Here, we demonstrate that while this synthetic lethal interaction relies upon components of both the intrinsic and extrinsic apoptotic pathways (e.g., BAX and BID), it is not due to significant ATM effects on the expression of p53 target genes. Instead, loss of ATM activity results in increased mitochondria and reactive oxygen species that drive apoptosis. Finally, we provide evidence that pharmacologic inhibition of ATM blocks autophagy in direct opposition to p53, which activates this process, and that inhibition of autophagy is sufficient to elicit an apoptotic response when combined with Nutlin-3. 相似文献
2.
Palaniappan Senthilkumar Jing Long Raparla Swetha Vaidyanathan Shruthi Rui-Rui Wang Srinivasan Preethi 《Nucleosides, nucleotides & nucleic acids》2013,32(2):89-102
Twelve novel zidovudine derivatives were prepared by modifying 5 ′-hydroxyl group of sugar moiety (1–8) and 5-methyl group of thymidine nucleus (9–12) and characterized spectrally. The compounds were evaluated for anti-HIV-1, antitubercular and antibacterial activities. Compound (3-azido-tetrahydro-5- (3,4-dihydro-5-methyl-2,4-dioxopyrimidin- 1 (2H)-yl) furan-2-yl)methyl 7- (4- (2-phenylacetoyloxy) -3,5- dimethylpiperazin-1-yl) -5- (2-phenylacetoyloxyamino) -1-cyclopropyl-6,8-difluoro-1,4-dihydro-4-oxoquinoline-3-carboxylate (5) was found to be the most potent anti-HIV-1 agent with EC50 of 0.0012 μM against HIV-1IIIB and CC50 of 34.05 μM against MT-4 with selectivity index of 28,375. Compound 5 inhibited Mycobacterium tuberculosis with MIC of 1.72 μM and inhibited four pathogenic bacteria with MIC of less than 1 μM. 相似文献
3.
Temperature‐compensated cell production rate and elongation zone length in the root of Arabidopsis thaliana 下载免费PDF全文
Xiaoli Yang Gang Dong K. Palaniappan Guohua Mi Tobias I. Baskin 《Plant, cell & environment》2017,40(2):264-276
To understand how root growth responds to temperature, we used kinematic analysis to quantify division and expansion parameters in the root of Arabidopsis thaliana. Plants were grown at temperatures from 15 to 30 °C, given continuously from germination. Over these temperatures, root length varies more than threefold in the wild type but by only twofold in a double mutant for phytochrome‐interacting factor 4 and 5. For kinematics, the spatial profile of velocity was obtained with new software, Stripflow. We find that 30 °C truncates the elongation zone and curtails cell production, responses that probably reflect the elicitation of a common pathway for handling severe stresses. Curiously, rates of cell division at all temperatures are closely correlated with rates of radial expansion. Between 15 to 25 °C, root growth rate, maximal elemental elongation rate, and final cell length scale positively with temperature whereas the length of the meristem scales negatively. Non‐linear temperature scaling characterizes meristem cell number, time to transit through either meristem or elongation zone, and average cell division rate. Surprisingly, the length of the elongation zone and the total rate of cell production are temperature invariant, constancies that have implications for our understanding of how the underlying cellular processes are integrated. 相似文献
4.
Islam Md. Rashedul Trivedi Pankaj Palaniappan Pitchai Reddy M. S. Sa Tongmin 《World journal of microbiology & biotechnology》2009,25(6):1115-1117
The present study was undertaken to observe the effects of chemical fertilizers and compost amendments on microbial community
structure in rice based cropping system under long term fertilizer application experiment. Changes in microbial community
structure assessed by the relative abundance of fatty acid methyl ester (FAME) profiles revealed that compost amendments led
to promoting the abundance of Gram-positive bacterial FAMEs. Multivariate analysis of FAME profiles separated the treatments
primarily on the basis of the amount of added compost. A link between different fertilizer application treatment and soil
microbial components was tentatively established, but it needs to be verified in further studies. 相似文献
5.
Dharmarajan Sriram Perumal Yogeeswari Prathiba Dhakla Palaniappan Senthilkumar Debjani Banerjee Thimmappa H. Manjashetty 《Bioorganic & medicinal chemistry letters》2009,19(4):1152-1154
Eighteen 5-nitrofuran-2-yl derivatives were prepared by reacting 5-nitro-2-furfural with various (sub)phenyl/pyridyl thiosemicarbazide using microwave irradiation. The compounds were tested for their in vitro activity against tubercular and various non-tubercular mycobacterium species in log-phase and 6-week-starved cultures. Compound N-(3,5-dibromopyridin-2-yl)-2-((5-nitrofuran-2-yl)methylene)hydrazinecarbothioamide (4r) was found to be the most potent compound (MIC: 0.22 μM) and was 3 times more active than standard isoniazid (INH) and equally active as rifampicin (RIF) in log-phase culture of Mycobacterium tuberculosis H37Rv. In starved M. tuberculosis H37Rv, 4r inhibited with MIC of 13.9 μM and was found to be 50 times more active than INH and slightly more active than RIF. 相似文献
6.
Woo-Jong Yim Selvaraj Poonguzhali Munusamy Madhaiyan Pitchai Palaniappan M. A. Siddikee Tongmin Sa 《Journal of microbiology (Seoul, Korea)》2009,47(2):147-155
Diazotrophic bacteria isolated from the rhizosphere of Chinese cabbage were assessed for other plant growth promoting characteristics
viz., production of IAA, ethylene, ACC deaminase, phosphate solubilization, and gnotobiotic root elongation. Their effect on inoculation
to Chinese cabbage was also observed under growth chamber conditions. A total of 19 strains that showed higher nitrogenase
activity identified by 16S rRNA gene sequence analysis were found to be the members of the genera Pseudomonas and Agrobacterium belonging to α- and γ-Proteobacteria groups. These strains were also efficient in producing IAA and ACC deaminase though they produced low levels of ethylene
and no phosphate solubilization. In addition, inoculation of selected diazotrophic bacterial strains significantly increased
seedling length, dry weight, and total nitrogen when compared to uninoculated control. The colonization of crop plants by
diazotrophic bacteria can be affected by many biotic and abiotic factors, and further studies are oriented towards investigating
the factors that could influence the establishment of a selected bacterial community. 相似文献
7.
Raman R Rajanikanth V Palaniappan RU Lin YP He H McDonough SP Sharma Y Chang YF 《PloS one》2010,5(12):e14377
Background
Many bacterial surface exposed proteins mediate the host-pathogen interaction more effectively in the presence of Ca2+. Leptospiral immunoglobulin-like (Lig) proteins, LigA and LigB, are surface exposed proteins containing Bacterial immunoglobulin like (Big) domains. The function of proteins which contain Big fold is not known. Based on the possible similarities of immunoglobulin and βγ-crystallin folds, we here explore the important question whether Ca2+ binds to a Big domains, which would provide a novel functional role of the proteins containing Big fold.Principal Findings
We selected six individual Big domains for this study (three from the conserved part of LigA and LigB, denoted as Lig A3, Lig A4, and LigBCon5; two from the variable region of LigA, i.e., 9th (Lig A9) and 10th repeats (Lig A10); and one from the variable region of LigB, i.e., LigBCen2. We have also studied the conserved region covering the three and six repeats (LigBCon1-3 and LigCon). All these proteins bind the calcium-mimic dye Stains-all. All the selected four domains bind Ca2+ with dissociation constants of 2–4 µM. Lig A9 and Lig A10 domains fold well with moderate thermal stability, have β-sheet conformation and form homodimers. Fluorescence spectra of Big domains show a specific doublet (at 317 and 330 nm), probably due to Trp interaction with a Phe residue. Equilibrium unfolding of selected Big domains is similar and follows a two-state model, suggesting the similarity in their fold.Conclusions
We demonstrate that the Lig are Ca2+-binding proteins, with Big domains harbouring the binding motif. We conclude that despite differences in sequence, a Big motif binds Ca2+. This work thus sets up a strong possibility for classifying the proteins containing Big domains as a novel family of Ca2+-binding proteins. Since Big domain is a part of many proteins in bacterial kingdom, we suggest a possible function these proteins via Ca2+ binding. 相似文献8.
Mavromatis K Abt B Brambilla E Lapidus A Copeland A Deshpande S Nolan M Lucas S Tice H Cheng JF Han C Detter JC Woyke T Goodwin L Pitluck S Held B Brettin T Tapia R Ivanova N Mikhailova N Pati A Liolios K Chen A Palaniappan K Land M Hauser L Chang YJ Jeffries CD Rohde M Göker M Bristow J Eisen JA Markowitz V Hugenholtz P Klenk HP Kyrpides NC 《Standards in genomic sciences》2010,2(3):290-299
Coraliomargarita akajimensis Yoon et al. 2007 is the type species of the genus Coraliomargarita. C. akajimensis is an obligately aerobic, Gram-negative, non-spore-forming, non-motile, spherical bacterium that was isolated from seawater surrounding the hard coral Galaxea fascicularis. C. akajimensis is of special interest because of its phylogenetic position in a genomically under-studied area of the bacterial diversity. Here we describe the features of this organism, together with the complete genome sequence, and annotation. This is the first complete genome sequence of a member of the family Puniceicoccaceae. The 3,750,771 bp long genome with its 3,137 protein-coding and 55 RNA genes is a part of the Genomic Encyclopedia of Bacteria and Archaea project. 相似文献
9.
Sikorski J Lapidus A Copeland A Glavina Del Rio T Nolan M Lucas S Chen F Tice H Cheng JF Saunders E Bruce D Goodwin L Pitluck S Ovchinnikova G Pati A Ivanova N Mavromatis K Chen A Palaniappan K Chain P Land M Hauser L Chang YJ Jeffries CD Brettin T Detter JC Han C Rohde M Lang E Spring S Göker M Bristow J Eisen JA Markowitz V Hugenholtz P Kyrpides NC Klenk HP 《Standards in genomic sciences》2010,2(2):149-157
Sulfurospirillum deleyianum Schumacher et al. 1993 is the type species of the genus Sulfurospirillum. S. deleyianum is a model organism for studying sulfur reduction and dissimilatory nitrate reduction as an energy source for growth. Also, it is a prominent model organism for studying the structural and functional characteristics of cytochrome c nitrite reductase. Here, we describe the features of this organism, together with the complete genome sequence and annotation. This is the first completed genome sequence of the genus Sulfurospirillum. The 2,306,351 bp long genome with its 2,291 protein-coding and 52 RNA genes is part of the Genomic Encyclopedia of Bacteria and Archaea project. 相似文献
10.
Mavromatis K Sikorski J Pabst E Teshima H Lapidus A Lucas S Nolan M Glavina Del Rio T Cheng JF Bruce D Goodwin L Pitluck S Liolios K Ivanova N Mikhailova N Pati A Chen A Palaniappan K Land M Hauser L Chang YJ Jeffries CD Rohde M Spring S Göker M Wirth R Woyke T Bristow J Eisen JA Markowitz V Hugenholtz P Klenk HP Kyrpides NC 《Standards in genomic sciences》2010,3(2):117-125
Vulcanisaeta distributa Itoh et al. 2002 belongs to the family Thermoproteaceae in the phylum Crenarchaeota. The genus Vulcanisaeta is characterized by a global distribution in hot and acidic springs. This is the first genome sequence from a member of the genus Vulcanisaeta and seventh genome sequence in the family Thermoproteaceae. The 2,374,137 bp long genome with its 2,544 protein-coding and 49 RNA genes is a part of the Genomic Encyclopedia of Bacteriaand Archaea project. 相似文献