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101.
Shivaji S Kholkute SD Verma SK Gaur A Umapathy G Singh A Sontakke S Shailaja K Reddy A Monika S Sivaram V Jyotsna B Bala S Ahmed MS Bala A Chandrashekar BV Gupta S Prakash S Singh L 《Indian journal of experimental biology》2003,41(7):710-723
Wild animals are an integral component of the ecosystem. Their decimation due to abrupt natural calamities or due to gradual human intervention would be disastrous to the ecosystem and would alter the balance in nature between various biotic components. Such an imbalance could have an adverse effect on the ecosystem. Therefore, there is an urgent need to put an end to the ever increasing list of endangered species by undertaking both in situ and ex situ conservation using tools of modern biology, to ascertain the degree of genetic variation and reproductive competence in these animals. This review highlights the development and use of molecular markers such as microsatellites, minisatellites, mitochondrial control region, cytochrome b and MHC loci to assess the genetic variation in various Indian wild animals such as the lion, tiger, leopard and deer. The review also presents data on the semen profile of the big cats of India. Reproductive technologies such as cryopreservation of semen and artificial insemination in big cats are also highlighted. 相似文献
102.
Eld's deer (Cervus eldi) is a highly endangered cervid, distributed historically throughout much of South Asia and Indochina. We analysed variation in the mitochondrial DNA (mtDNA) control region for representatives of all three Eld's deer subspecies to gain a better understanding of the genetic population structure and evolutionary history of this species. A phylogeny of mtDNA haplotypes indicates that the critically endangered and ecologically divergent C. eldi eldi is related more closely to C. e. thamin than to C. e. siamensis, a result that is consistent with biogeographic considerations. The results also suggest a strong degree of phylogeographic structure both between subspecies and among populations within subspecies, suggesting that dispersal of individuals between populations has been very limited historically. Haplotype diversity was relatively high for two of the three subspecies (thamin and siamensis), indicating that recent population declines have not yet substantially eroded genetic diversity. In contrast, we found no haplotype variation within C. eldi eldi or the Hainan Island population of C. eldi siamensis, two populations which are known to have suffered severe population bottlenecks. We also compared levels of haplotype and nucleotide diversity in an unmanaged captive population, a managed captive population and a relatively healthy wild population. Diversity indices were higher in the latter two, suggesting the efficacy of well-designed breeding programmes for maintaining genetic diversity in captivity. Based on significant genetic differentiation among Eld's deer subspecies, we recommend the continued management of this species in three distinct evolutionarily significant units (ESUs). Where possible, it may be advisable to translocate individuals between isolated populations within a subspecies to maintain levels of genetic variation in remaining Eld's deer populations. 相似文献
103.
Sarkar Varun Kumar De Ujjwal Kumar Kala Anju Verma Ashok Kumar Chauhan Anuj Paul Babul Rudra Soni Srishti Gandhar Jitendra Singh Chaudhuri Pallab Patra Manas Kumar Eregowda Chethan Gollahalli Gaur Gyanendra Kumar 《Probiotics and antimicrobial proteins》2023,15(1):149-159
Probiotics and Antimicrobial Proteins - The aim of this study was to determine the effects of early-life bovine lactoferrin and host specific probiotic interventions on growth performance,... 相似文献
104.
Role of Petiole in Protein Metabolism of Senescing Betel (Piper betle L.) Leaves 总被引:1,自引:1,他引:0
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Effects of depetiolation on protein metabolism during senescence of detached betel (Piper betle L.) leaves have been studied. In normal petiolated leaves, the level of chlorophyll and proteins and extent of protein synthesis declined, while the protease activity registered manifold increase with the advancement of senescence. All of these changes were delayed by depetiolation/de-midribbing treatments, though without affecting the general pattern of senescence. Thus, the presence of petiole seems to expedite protein degradation, probably due to earlier attainment of optimal concentration of proposed senescence factor(s) (Mishra and Gaur 1970 Science 167: 387). 相似文献
105.
Somatic chromosome complements of five sympatric species of the genus Parasarcophaga, viz. P. misera, P. albiceps, P. argyrostoma, P. ruficornis and P. knabi, are described. All the species have five pairs of meta/submetacentric autosomes and an XX/XY sex chromosome pair which is highly variable in size and shape. In P. misera and P. albiceps they are tiny dots while in P. knabi the metacentric X and Y chromosomes constitute almost one third of the genome. In P. ruficornis and P. argyrostoma they are telocentric chromosomes of moderate size. A comparative study of the C-banding patterns of P. ruficornis, P. knabi, P. argyrostoma and P. misera shows that autosomes of the former three species possess characteristic C-bands in pericentric regions while in P. misera they are absent. The heterochromatic sex chromosomes are C-band positive in all the species. However, with the exception of the tiny sex chromosomes of P. misera, the X chromosomes of other species show shorter or longer regions which stain rather lightly. These C-banded areas correspond to the heterochromatic areas revealed in orcein stained preparations. The evolutionary implications of these results are discussed. 相似文献
106.
N K Gaur A Kumar G K Garg 《Biochemical and biophysical research communications》1981,101(4):1200-1208
A laboratory isolate of could grow and sporulate on an amino acid, viz., alanine or glutamate or aspartate as single source of carbon and nitrogen. It failed to sporulate if the amino acid was replaced by the corresponding keto acid and ammonium sulphate in the medium, although, normal growth was observed. One of the key enzymes in nitrogen assimilation, the glutamine synthetase, has been purified by DE-52 and affinity column chromatography from both alanine and pyruvate grown cells. The kinetic and other properties of both of these enzymes were studied. The enzyme isolated from alanine grown cells differed significantly from that isolated from pyruvate grown cells (viz.,pH optima, response to Mg++ and other effectors). A possible role of glutamine synthetase in the initiation of bacterial sporulation is discussed. 相似文献
107.
108.
Laboratory-based bioassay experiments using Selenastrum capricornutum PRINTZ as the test organism were conducted to evaluate the potentiality of refinery effluents to sustain algal growth. The raw effluents were remarkably toxic to the test alga, but satisfactory algal growth occurred in (diluted) 0.01 % effluents. The effluents from subsequent treatment stages required much less dilution to eliminate the toxicity. This study implicates oil and phenol in the reduction of algal growth in refinery effluents. A highly significant negative correlation was found between the final yield of the test alga and the concentration of oil or phenol in the culture suspension. The bioassay experiments therefore point to the toxic nature of refinery effluents. On the basis of these findings it is recommended that proper dilution of refinery effluents is necessary before they are discharged into any body of water. 相似文献
109.
3D QSAR studies namely CoMFA, advance CoMFA and CoMSIA have been carried out on a series of pyrroloquinazolines for their thrombin receptor antagonistic activity. The predicted activities by highly significant CoMFA (q2=0.66 and CoMSIA (q2=0.67) models were in good accordance with observed activities and the models may be useful for optimization of thrombin receptor antagonistic activity. 相似文献
110.
Bentley JM Adams DR Bebbington D Benwell KR Bickerdike MJ Davidson JE Dawson CE Dourish CT Duncton MA Gaur S George AR Giles PR Hamlyn RJ Kennett GA Knight AR Malcolm CS Mansell HL Misra A Monck NJ Pratt RM Quirk K Roffey JR Vickers SP Cliffe IA 《Bioorganic & medicinal chemistry letters》2004,14(9):2367-2370
A series of 1-(1-indolinyl)-2-propylamines was synthesised and evaluated as 5-HT(2C) receptor agonists for the treatment of obesity. The general methods of synthesis of the precursor indoles are described. The functional efficacy and radioligand binding data for all of the compounds at 5-HT(2) receptor subtypes are reported. A number of compounds were found to reduce food intake in rats after oral administration. 相似文献