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1.
M. K. Chandrashekaran G. Marimuthu R. Subbaraj P. Kumarasamy M. S. Ramkumar K. Sripathi 《Journal of biosciences》1991,16(3):97-101
Several bodily functions in humans vary on a 24 h pattern and most of these variations persist with a circadian period ofca 25 h when subjects are studied under conditions of social and temporal isolation. We report in this paper that the estimates
of short time intervals (TE) of 2 h are strongly coupled to the circadian rhythm in sleepwakefulness. There is a linear correlation
between the number of hours humans stay awake (α) and their estimation of 2 h intervals. The coupling of TE to α appears to
obtain only under conditions of physical well-being. 相似文献
2.
The neuropeptide galanin comes under the powerful and versatile modulators of classical neurotransmitters and is present in brain tissues, which are intimately involved in epileptogenesis. It acts as appealing targets for studying basic mechanisms of seizure initiation and arrest, and for the development of novel approaches for various neurodegenerative diseases. Galanin is widely distributed in the mammalian brain which controls various processes such as sensation of pain, learning, feeding, sexual behaviour, carcinogenesis, pathophysiology of neuroendocrine tumors and others. The function of galanin can be exploited through its interaction with three G-protein coupled receptors subtypes such as GalR1, GalR2 and GalR3. The N-terminal region of galanin comprises about highly conserved 15 amino acid residues, which act as the crucial region for agonist-receptor binding. We have constructed a theoretical structural model for the N-terminal region of galanin from Homo sapiens by homology modeling. The stereochemistry of the model was checked using PROCHECK. The functionally conserved regions were identified by surface mapping of phylogenetic information generated by online web algorithm ConSurf. The docking studies on the pharmacologically important galanin receptors with the theoretical model of N-terminal region of galanin predicted crucial residues for binding which would be useful in the development of novel leads for neurodegenerative disorders. 相似文献
3.
Kannan Karuppiah Sivaranjani Sekar Kumar Rajendran Karuppasamy Karuthapandian Prabhu N. Marimuthu Kannapiran Ethiraj 《Zeitschrift fur angewandte Ichthyologie》2021,37(2):367-369
Length-weight relationship (LWR) parameters were analysed for six demersal finfish species from the Gulf of Mannar coast, Bay of Bengal. Fishes were sampled monthly from the landings of trawlers operated along the coast of Tuticorin and Rameshwaram with a cod-end mesh size of 35 mm at the depth of 60–80 m. Fish specimens were sampled by measuring the total length (TL) and total weight (TW) with precision to 0.1 cm and 0.1 g respectively. The present study also recorded a new maximum total length for Engyprosopon macrolepis, Torquigener brevipinnis and Leiognathus brevirostris. 相似文献
4.
Saraswathi Umavathi Shahid Mahboob Marimuthu Govindarajan Khalid A. Al-Ghanim Zubair Ahmed P. Virik Norah Al-Mulhm Murugesh Subash Kasi Gopinath C. Kavitha 《Saudi Journal of Biological Sciences》2021,28(3):1808-1815
The present work aims to synthesize zinc oxide (ZnO) nanoparticles via green approaches using leaf extract of Parthenium hysterophorus. UV–vis and FT-IR tests confirmed the existence of biomolecules, active materials, and metal oxides. The X-ray diffraction structural study exposes the ZnO nanoparticles formation with hexagonal phase structures. SEM and TEM analysis reveal surface morphologies of ZnO nanoparticles and most of them are spherical with a size range of 10 nm. ZnO nanoparticles were revealed strong antimicrobial activity against both bacterial and fungal strains. The germination of seeds and vegetative growth of Sesamum indicum has been greatly improved. 相似文献
5.
D. Jeya Sundara Sharmila K. Veluraja 《Journal of biomolecular structure & dynamics》2013,31(6):641-656
Abstract Molecular mechanics and molecular dynamics studies are performed to investigate the conformational preference of cell surface higher gangliosides (GT1A and GT1B) and their interaction with Cholera Toxin. The water mediated hydrogen bonding network exists between sugar residues in gangliosides. An integrated molecular modeling, molecular mechanics, and molecular dynamics calculation of cholera toxin complexed with GT1A and GT1B reveal that, the active site of cholera toxin can accommodate these higher gangliosides. Direct and water mediated hydrogen bonding interactions stabilize these binding modes and play an essential role in defining the order of specificity for different higher ganglioside towards cholera toxin. This study identifies that the binding site of cholera toxin is shallow and can accommodate a maximum of two NeuNAc residues. The NeuNAc binding site of cholera toxin may be crucial for the design of inhibitors that can prevent the infection of cholera. 相似文献
6.
Summary Physiological and biochemical responses of micropropagated tea plants grown under field conditions were investigated in comparison
to vegetatively propagated (VP) plants. No significant variation was observed between tissue culture raised (TC) and VP plants
in terms of photosynthetic carbon assimilation rate. However, clones showed significant variation among themselves. Carbon
assimilation studies carried out with a radiotracer technique revealed that ‘Assam’ cultivar UPASI-27 assimilated a higher
amount of labeled carbon dioxide followed by UPASI-3. However, UPASI-27 was marginally better than UPASI-3 in terms of mobilization
of assimilates to the growing sinks. Both, UPASI-3 and UPASI-27 reassimilated higher quantities of photosynthates followed
by BSB-1 and UPASI-26. Though there was a marginal variation in photosynthetic pigments of TC and VP plants, it was not statistically
significant. Similarly, no significant variations were observed in certain substrates (polyphenols, catechins and amino acids)
and enzymes (polyphenol oxidase, peroxidase and phenylalanine ammonia-lyase) except protease involved in the formation of
quality constituents of made tea. However, clonal variation was evident with respect to photosynthetic pigments, substrates/enzymes.
Under soil moisture stress, no significant variation was observed between VP and TC plants in terms of proline accumulation. 相似文献
7.
Kelkar DS Kumar D Kumar P Balakrishnan L Muthusamy B Yadav AK Shrivastava P Marimuthu A Anand S Sundaram H Kingsbury R Harsha HC Nair B Prasad TS Chauhan DS Katoch K Katoch VM Kumar P Chaerkady R Ramachandran S Dash D Pandey A 《Molecular & cellular proteomics : MCP》2011,10(12):M111.011627
The genome sequencing of H37Rv strain of Mycobacterium tuberculosis was completed in 1998 followed by the whole genome sequencing of a clinical isolate, CDC1551 in 2002. Since then, the genomic sequences of a number of other strains have become available making it one of the better studied pathogenic bacterial species at the genomic level. However, annotation of its genome remains challenging because of high GC content and dissimilarity to other model prokaryotes. To this end, we carried out an in-depth proteogenomic analysis of the M. tuberculosis H37Rv strain using Fourier transform mass spectrometry with high resolution at both MS and tandem MS levels. In all, we identified 3176 proteins from Mycobacterium tuberculosis representing ~80% of its total predicted gene count. In addition to protein database search, we carried out a genome database search, which led to identification of ~250 novel peptides. Based on these novel genome search-specific peptides, we discovered 41 novel protein coding genes in the H37Rv genome. Using peptide evidence and alternative gene prediction tools, we also corrected 79 gene models. Finally, mass spectrometric data from N terminus-derived peptides confirmed 727 existing annotations for translational start sites while correcting those for 33 proteins. We report creation of a high confidence set of protein coding regions in Mycobacterium tuberculosis genome obtained by high resolution tandem mass-spectrometry at both precursor and fragment detection steps for the first time. This proteogenomic approach should be generally applicable to other organisms whose genomes have already been sequenced for obtaining a more accurate catalogue of protein-coding genes. 相似文献
8.
Jeyasekaran G. Raj K. Thirumalai Shakila R. Jeya Thangarani A. Jemila Sukumar D. Jailani V. Abdul Kadhar 《World journal of microbiology & biotechnology》2011,27(4):953-959
A multiplex PCR based assay was developed for the identification of the genus Salmonella. Five sets of primers from different genomic sequences such as fimA, himA,
hns, invA and hto genes were selected for the identification of serogroups of Salmonella
enterica such as S. Typhi, S. ParatyphiA, S. Typhimurium, S. Enteritidis and S. Weltevreden. The selected primers amplified products with the sizes of 85, 123, 152, 275 and 496 bp, respectively, for the
genus Salmonella. This assay was found to be highly sensitive, as it could detect 5 cells of Salmonella and 1,000 fg of genomic DNA. Amplification of DNA extracted from other genera viz. V. cholerae and E. coli yielded negative results. This assay provides specific and reliable results and allows for the cost–effective detection of
Salmonella in one reaction tube in mixed bacterial communities. 相似文献
9.
Immobilization of Bacillus licheniformis
l-arabinose isomerase (BLAI) on aminopropyl glass modified with glutaraldehyde (4 mg protein g support−1) was found to enhance the enzyme activity. The immobilization yield of BLAI was proportional to the quantity of amino groups
on the surface of support. Reducing particle size increased the adsorption capacity (q
m) and affinity (k
a). The pH and temperature for immobilization were optimized to be pH 7.1 and 33°C using response surface methodology (RSM).
The immobilized enzyme was characterized and compared to the free enzyme. There is no change in optimal pH and temperature
before and after immobilization. However, the immobilized BLAI enzyme achieved 145% of the activity of the free enzyme. Correspondingly,
the catalytic efficiency (k
cat/K
m) was improved 1.47-fold after immobilization compared to the free enzyme. The thermal stability was improved 138-fold (t
1/2 increased from 2 to 275 h) at 50°C following immobilization. 相似文献
10.
Hee-Jung Moon Marimuthu Jeya In-Sik Yu Jung-Hwan Ji Deok-Kun Oh Jung-Kul Lee 《Applied microbiology and biotechnology》2009,83(2):329-337
α-Lipoic acid (LA), a naturally occurring cofactor reported to be present in a diverse group of microorganisms, plants, and
animal tissues, has been widely and successfully used as a therapy for a variety of diseases, including diabetes and heart
disease. However, to date, recombinant DNA technology has not been applied for higher LA production due mainly to difficulties
in the functional expression of key enzymes involved in LA production. Here, we report a study for higher LA production with
the aid of chaperone plasmids, DnaKJE and trigger factor (Tf). The lipA and lplA genes encoding lipoate synthase and lipoate protein ligase in Pseudomonas fluorescens, respectively, were cloned and transformed into Escherichia coli K12. When they were overexpressed in E. coli, both LipA and LplA were expressed as inclusion bodies leading to no increase in LA production. However, when chaperone plasmids
DnaKJE and Tf were coexpressed with lipA and lplA, the resulting recombinant E. coli strains showed higher LA production than the wild-type E. coli by 32–111%, respectively. 相似文献