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21.
Anu Arya Divya Mathur Abhilash Tyagi Rajesh Kumar Vinod Kumar Carl E. Olsen 《Nucleosides, nucleotides & nucleic acids》2013,32(12):646-659
An efficient protocol has been developed for the synthesis of a small library of 3′-deoxy-3′-(4-substituted-triazol-1-yl)-5-methyluridine using Cu(I)-catalyzed Huisgen–Sharpless–Meldal 1,3-dipolar cycloaddition reaction of 3′-azido-3′-deoxy-5-methyluridine with different alkynes under optimized condition in an overall yields of 76%–92%. Here, the azido precursor compound, i.e., 3′-azido-3′-deoxy-5-methyluridine was chemoenzymatically synthesized from D-xylose in good yield. Some of the alkynes used in cycloaddition reaction were synthesized by the reaction of hydroxycoumarins or naphthols with propargyl bromide in acetone using K2CO3in excellent yields. All synthesized compounds were unambiguously identified on the basis of their spectral (IR, 1H-, 13C NMR spectra, and high-resolution mass spectra) data analysis. 相似文献
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23.
Kate Daine Keith Hawton Vinod Singaravelu Anne Stewart Sue Simkin Paul Montgomery 《PloS one》2013,8(10)
Background
There is concern that the internet is playing an increasing role in self-harm and suicide. In this study we systematically review and analyse research literature to determine whether there is evidence that the internet influences the risk of self-harm or suicide in young people.Methods
An electronic literature search was conducted using the PsycINFO, MEDLINE, EMBASE, Scopus, and CINAHL databases. Articles of interest were those that included empirical data on the internet, self-harm or suicide, and young people. The articles were initially screened based on titles and abstracts, then by review of the full publications, after which those included in the review were subjected to data extraction, thematic analysis and quality rating.Results
Youth who self-harm or are suicidal often make use of the internet. It is most commonly used for constructive reasons such as seeking support and coping strategies, but may exert a negative influence, normalising self-harm and potentially discouraging disclosure or professional help-seeking. The internet has created channels of communication that can be misused to ‘cyber-bully’ peers; both cyber-bullying and general internet use have been found to correlate with increased risk of self-harm, suicidal ideation, and depression. Correlations have also been found between internet exposure and violent methods of self-harm.Conclusions
Internet use may exert both positive and negative effects on young people at risk of self-harm or suicide. Careful high quality research is needed to better understand how internet media may exert negative influences and should also focus on how the internet might be utilised to intervene with vulnerable young people. 相似文献24.
25.
Darío C. Colautti Leandro Miranda Mariano Gonzalez-Castro Vanina Villanova Carlos A. Strüssmann Miguel Mancini Tomas Maiztegui Gustavo Berasain Ricardo Hattori Fabian Grosman Pablo Sanzano Ismael Lozano Sabina L. Vegh Victor Salinas Omar Del Ponti Pamela del Fresno Priscila Minotti Yoji Yamamoto Claudio R. M. Baigún 《Journal of fish biology》2020,96(1):202-216
In South America, the order Atheriniformes includes the monophyletic genus Odontesthes with 20 species that inhabit freshwater, estuarine and coastal environments. Pejerrey Odontesthes argentinensis is widely distributed in coastal and estuarine areas of the Atlantic Ocean and is known to foray into estuaries of river systems, particularly in conditions of elevated salinity. However, to our knowledge, a landlocked self-sustaining population has never been recorded. In this study, we examined the pejerrey population of Salada de Pedro Luro Lake (south-east of Buenos Aires Province, Argentina) to clarify its taxonomic identity. An integrative taxonomic analysis based on traditional meristic, landmark-based morphometrics and genetic techniques suggests that the Salada de Pedro Luro pejerrey population represents a novel case of physiological and morphological adaptation of a marine pejerrey species to a landlocked environment and emphasises the environmental plasticity of this group of fishes. 相似文献
26.
Gupta Praveen Kumar Vaswani Shalini Kumar Vinod Roy Debashis Kumar Muneendra Kushwaha Raju Kumar Avinash Shukla Amit 《Biological trace element research》2020,194(2):379-389
Biological Trace Element Research - This study was conducted to investigate the effect of vanadium (V) supplementation on growth, metabolism, antioxidant, and immunological and endocrine variables... 相似文献
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Tabreiz Ahmad Khan Riyaz Ahmad Dar 《Archives Of Phytopathology And Plant Protection》2013,46(3):189-193
The significant reduction in the plant growth was observed at an initial inoculum level of 2 immature females of Rotylenchulus reniformis/g soil and hence this inoculum level was considered as the minimum damaging threshold level for broccoli. The population of reniform nematode increased with the increasing levels of inoculum. Though, the maximum nematode population was recorded at the highest level of inoculum, the rate of reproduction of nematode was found to be highest at the lowest level of initial inoculum. Symptoms like chlorosis, stunted growth, shedding of leaves, early sprouting of inflorescence and sparsely developed roots were found during the experimental studies. Rotylenchulus reniformis required 30 days to complete the life cycle on broccoli. 相似文献
29.
Michela Ombelli Lauren Costello Corinne Postle Vinod Anantharaman Qing Cheng Meng Russell J. Composto 《Biofouling》2013,29(5):505-518
Adsorption of bovine serum albumin (BSA) and fibrinogen (Fg) was measured on six distinct bare and dextran- and hyaluronate-modified silicon surfaces created using two dextran grafting densities and three hyaluronic acid (HA) sodium salts derived from human umbilical cord, rooster comb and Streptococcus zooepidemicus. Film thickness and surface morphology depended on the HA molecular weight and concentration. BSA coverage was enhanced on surfaces in competitive adsorption of BSA:Fg mixtures. Dextranization differentially reduced protein adsorption onto surfaces based on oxidation state. Hyaluronization was demonstrated to provide the greatest resistance to protein coverage, equivalent to that of the most resistant dextranized surface. Resistance to protein adsorption was independent of the type of HA utilized. With changing bulk protein concentration from 20 to 40 μg ml?1 for each species, Fg coverage on silicon increased by 4x, whereas both BSA and Fg adsorption on dextran and HA were far less dependent on protein bulk concentration. 相似文献
30.
Vinod Jani Uddhavesh B. Sonavane Rajendra Joshi 《Journal of biomolecular structure & dynamics》2013,31(6):845-860
Abstract Reaching the experimental time scale of millisecond is a grand challenge for protein folding simulations. The development of advanced Molecular Dynamics techniques like Replica Exchange Molecular Dynamics (REMD) makes it possible to reach these experimental timescales. In this study, an attempt has been made to reach the multi microsecond simulation time scale by carrying out folding simulations on a three helix bundle protein, Villin, by combining REMD and Amber United Atom model. Twenty replicas having different temperatures ranging from 295 K to 390 K were simulated for 1.5 μs each. The lowest Root Mean Square Deviation (RMSD) structure of 2.5 Å was obtained with respect to native structure (PDB code 1VII), with all the helices formed. The folding population landscapes were built using segment-wise RMSD and Principal Components as reaction coordinates. These analyses suggest the two-stage folding for Villin. The combination of REMD and Amber United Atom model may be useful to understand the folding mechanism of various fast folding proteins 相似文献