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1.
Eriocaulon raipurense (Eriocaulaceae) is described and illustrated as a new species from Madhya Pradesh, India. The species is closely allied to E. hamiltonianum but differs in the size and apex of involucral bancts, white-pilose nature of floral bracts and colour of female petals. 相似文献
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Sequencing and expression of the Butyrivibrio fibrisolvens xylB gene encoding a novel bifunctional protein with beta-D-xylosidase and alpha-L-arabinofuranosidase activities. 总被引:5,自引:4,他引:1 下载免费PDF全文
A single gene (xylB) encoding both beta-D-xylosidase (EC 3.2.1.37) and alpha-L-arabinofuranosidase (EC 3.2.1.55) activities was identified and sequenced from the ruminal bacterium Butyrivibrio fibrisolvens. The xylB gene consists of a 1.551-bp open reading frame (ORF) encoding 517 amino acids. A subclone containing a 1.843-bp DNA fragment retained both enzymatic activities. Insertion of a 10-bp NotI linker into the EcoRV site within the central region of this ORF abolished both activities. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis of cytoplasmic proteins from recombinant Escherichia coli confirmed the presence of a 60,000-molecular-weight protein in active subclones and the absence of this protein in subclones lacking activity. With p-nitrophenyl-beta-D-xylopyranoside and p-nitrophenyl-alpha-L-arabinofuranoside as substrates, the specific activity of arabinosidase was found to be approximately 1.6-fold higher than that of xylosidase. The deduced amino acid sequence of the xylB gene product did not exhibit a high degree of identity with other xylan-degrading enzymes or glycosidases. The xylB gene was located between two incomplete ORFs within the 4,200-bp region which was sequenced. No sequences resembling terminators were found within this region, and these three genes are proposed to be part of a single operon. Based on comparison with other glycosidases, a conserved region was identified in the carboxyl end of the translated xylB gene which is similar to that of glucoamylase from Aspergillus niger. 相似文献
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Plasmonics - In the present work, a highly sensitive SPR biosensor based on silver (Ag), barium titanate (BaTiO3), graphene, and affinity layer is proposed for the detection of Pseudomonas... 相似文献
5.
Vivek Kumar Mukesh M. Mudgal Nidhi Rani Amrita Jha Manu Jaggi Anu T. Singh 《Journal of enzyme inhibition and medicinal chemistry》2013,28(3):763-770
A new series of functionalized amino acid derivatives N-substituted 1-N-(tert-butoxycarbonyl)-2,2-dimethyl-4-phenyl-5-oxazolidine carboxamide (1-17) and 1-N-substituted-3-amino-2-hydroxy-3-phenylpropane-1-carboxamide (18-34) were synthesized and evaluated for their in vitro cytotoxicity against human cancer cell lines. Compound 6 has shown interesting cytotoxicity (IC50 = 5.67 μm) in ovarian cancer, while compound 10 exhibited promising cytotoxicity in ovarian (IC50 = 6.1 μm) and oral (IC50 = 4.17 μm) cancers. These compounds could be of use in designing new anti-cancer agents. 相似文献
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Colin W. Garvie Keshav Vasanthavada Qing Xiang 《Biochimica et Biophysica Acta - Proteins and Proteomics》2013,1834(8):1562-1571
RNase L is part of the innate immune response to viral infection. It is activated by a small oligonucleotide (2–5A) whose synthesis is initiated as part of the interferon response. Binding of 2–5A to the N-terminal regulatory region, the ANK domain, of RNase L activates its ribonuclease activity and results in cleavage of RNA in the cell, which ultimately leads to apoptosis of the infected cell. The mechanism by which 2–5A activates the ribonuclease activity of RNase L is currently unclear but 2–5A has been shown to induce dimerization of RNase L. To investigate the importance of dimerization of RNase L, we developed a 15 kDa dimerization-inducing protein domain that was fused to the N-terminus of RNase L. From these studies we provide direct evidence that dimerization of RNase L occurs at physiologically relevant protein concentrations and correlates with activation of ribonuclease activity. We also show that the binding of 2–5A to RNase L promotes dimerization of the ANK domain and suggest how this could transmit a signal to the rest of the protein to activate ribonuclease activity. Finally, we show that the dimerization-inducing domain can be used as a general fusion partner to aid in protein expression and purification. 相似文献
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On the basis of stereo specific information obtained from crystal structures of CDK2, indole and chromene analogues were designed by suitably substituting the pharmacophores on their moiety and docked with target protein for calculating binding affinities. The binding affinities are represented in glide score. (5E)-5-[(1-methyl-1H-indol-3-yl)methylidene]-2,4,6-trioxotetrahydro-2H-pyrimidin-1-ide (I1), (5E)-5-(1H-indol-3-ylmethylidene)-2,4,6-trioxotetrahydro-2H-pyrimidin-1-ide (I2) and 2-amino-4-(4-methyl phenyl)-5-oxo-5,6,7,8-tetrahydro-4H-chromene-3-carbonitrile (C9) were selected for synthesis and biological testing based on vital interactions. (5E)-5-(1H-indol-3-ylmethylidene)-2,4,6-trioxotetrahydro-2H-pyrimidin-1-ide(I2) and 2-amino-4-(4-methyl phenyl)-5-oxo-5,6,7,8-tetrahydro-4H-chromene-3-carbonitrile (C9) were proved to be active against MCF-7 and HeLa cell lines. 相似文献
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Wong Dorothy Plumb James Talab Hosamiddine Kurdi Mouhamad Pokhrel Keshav Oelkers Peter 《Mycopathologia》2019,184(2):213-226
Mycopathologia - Perturbing ergosterol synthesis has been previously shown to reduce the virulence of Candida albicans. We tested the hypothesis that further altering cell membrane composition by... 相似文献
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Mahima Chaudhary Anil Kumar Garg Ganesh Kumar Mittal Vishal Mudgal 《Biological trace element research》2010,133(2):217-226
Forty weaned male guinea pigs (Cavia porcellus) of 152.6?±?7.96 g mean body weight were divided into four equal groups and fed a common basal diet comprised of 25% ground cowpea (Vigna unguiculata) hay, 30% ground maize (Zea mays) grain, 22% ground gram (Cicer arietinum) grain, 9.5% deoiled rice (Oryza sativa) bran, 6% soybean (Glycine max) meal, 6% fish meal, 1.5% mineral mixture (without Se), and ascorbic acid at 200 mg/kg to meet their nutrient requirements along with 0, 0.1, 0.2, and 0.3 ppm of organic selenium (Se) in groups I, II, III, and IV, respectively. Experimental feeding lasted for a period of 10 weeks, during which, daily feed intake and weekly body weights were recorded. Intake and digestibility of dry matter, organic matter, ether extract, crude fiber, and nitrogen-free extract as well as uptake of calcium and phosphorus were similar (P?>?0.05) among the four groups. Feed:gain ratio was also similar (P?>?0.05) in the four groups. However, digestibility of crude protein was significantly (P?<?0.001) higher in group II supplemented with 0.1 ppm organic Se as compared to other three group. Intake and absorption of Se was significantly (P?<?0.001) higher in all the Se supplemented groups as compared to control group. Average daily gain (ADG) was significantly (P?<?0.05) higher in group II (3.16 g/day) and III (3.38 g/day) as compared to group I (2.88 g/day). However, ADG in group IV (supplemented 0.3 ppm organic Se) was significantly (P?<?0.05) lower (2.83 g/day) than group II and III, but comparable (P?>?0.05) to group I. Findings of the present experiment suggests that Se requirements of guinea pigs are ≥0.2 ppm, as supplementation of 0.1 ppm organic Se in the diet (having 0.1 ppm Se) not only enhanced their growth rate but also improved the protein utilization. 相似文献
10.
Gajanan T Behere Wee Tek Tay Derek A Russell David G Heckel Belinda R Appleton Keshav R Kranthi Philip Batterham 《BMC evolutionary biology》2007,7(1):117