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排序方式: 共有382条查询结果,搜索用时 62 毫秒
81.
P. B. Kavi Kishor S. Anil Kumar Jalaja Naravula P. Hima Kumari Divya Kummari Rajasheker Guddimalli Sujatha Edupuganti Appa Rao Karumanchi Perumal Venkatachalam Prashanth Suravajhala Rathnagiri Polavarapu 《Physiology and Molecular Biology of Plants》2021,27(10):2433
Exploding global population, rapid urbanization, salinization of soils, decreasing arable land availability, groundwater resources, and dynamic climatic conditions pose impending damage to our food security by reducing the grain quality and quantity. This issue is further compounded in arid and semi-arid regions due to the shortage of irrigation water and erratic rainfalls. Millets are gluten (a family of proteins)-free and cultivated all over the globe for human consumption, fuel, feed, and fodder. They provide nutritional security for the under- and malnourished. With the deployment of strategies like foliar spray, traditional/marker-assisted breeding, identification of candidate genes for the translocation of important minerals, and genome-editing technologies, it is now tenable to biofortify important millets. Since the bioavailability of iron and zinc has been proven in human trials, the challenge is to make such grains accessible. This review encompasses nutritional benefits, progress made, challenges being encountered, and prospects of enriching millet crops with essential minerals. 相似文献
82.
Thirty five females and 15 males of New Zealand White mature rabbits about 6 months of age, were assigned to 1–5 dietary treatments (7 does+3 bucks for each): uncontaminated control diet, naturally aflatoxin contaminated diet without or with 1,2 and 3% bentonite. Rabbit fed with the aflatoxin-diet had a decreased (P<0.01 or 0.05) physical semen characteristics of bucks and a reproductive performance traits of does. The values of conception rate (%), gestation length (days), litter size (n) and litter weights (g) at birth and viability (%) of litters of doe rabbits, fed with the aflatoxin-diet, recorded, respectively: 64.5; 31.0; 4.4; 275.0 and 57.1 versus 85.6; 30.3; 7.9; 508.0; and 100 for those fed with the uncontaminated diet. Addition of bentonite to the aflatoxin contaminated diet improved in general the physical semen characteristics of buck and reproductive performance traits of doe rabbits. The results of the study demonstrate that adding 1% of Egyptian raw bentonite to the naturally aflatoxin contaminated rabbit diets can provide an effective, cheap and safe practical technique for preventing the aflatoxicosis in mature rabbits. 相似文献
83.
Biochemical changes associated with adventitious shoot regeneration during in vitro culture of hypocotyl explants of Jatropha integerrima were determined. Histological and biochemical studies were undertaken at 7-d intervals, up to four weeks on hypocotyl explants cultured on basal Murashige and Skoog's medium supplemented with 0.5 mg dm-3 N6-benzyladenine and 1.0 mg dm-3 indole-3-butyric acid. Initial cell proliferation occurred within one week of culture; meristemoid differentiation within two to three weeks and shoot development after four weeks. Peak activities of alkaline phosphatase, peroxidase and polyphenol oxidase was observed at day 14 indicating their involvement in the formation of meristematic centers. Protein accumulation and acid phosphatase activity were maximum at day 28. 相似文献
84.
85.
Obesity‐induced mitochondrial dysfunction in porcine adipose tissue‐derived mesenchymal stem cells
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86.
Compensatory substitutions and the evolution of the mitochondrial 12S rRNA gene in mammals 总被引:5,自引:2,他引:3
12S ribosomal RNA (rRNA) gene sequences from a suite of mammalian taxa (13
placentals, 4 marsupials, 1 monotreme), for which phylogenetic
relationships are well established based on independent criteria, were
employed to study the evolution of this gene. Phylogenetic analysis of 12S
sequences produces a phylogeny that agrees with expectations. Base
composition provides evidence for directional symmetrical substitution
pressure in loops; in stems, base composition is much more even. Rates of
nucleotide substitution are lower in stems than loops. Patterns of
nucleotide substitution show an overall preference for transitions over
transversions, with this difference more profound in stems than loops.
Among different transversion pathways, there is a wide range of
transformation frequencies. An analysis of compensatory substitutions shows
that there is strong evidence for their occurrence and that a weighting
factor of 0.61 should be applied in phylogenetic analyses to account for
the dependence of mutations at stem positions relative to positions where
changes are independent. Among stem variables (i.e., stem length,
interaction distance, substitution rates, G+C content, and the percentage
of bases that are paired), several significant correlations were
discovered, but stem length and interaction distance are uncorrelated with
other variables.
相似文献
87.
We investigated the prevalence and phenotypic variation of Candida species in oral lichen planus (OLP) and the therapeutic implications of our findings. Eighty patients with clinically and histopathologically confirmed cases of OLP (64 non-erosive, 16 erosive) and a control group of 80 healthy individuals with no predisposing factors for oral candidiasis were examined for evidence of Candida infection. Oral swabs and smears were obtained for cytology and culture. Identification, speciation and antifungal susceptibility tests of Candida isolates were performed using an automated microbial identification system. Fifty percent of erosive OLP cases, 28% of non-erosive cases and none of the controls showed evidence of Candida. Candida albicans was found predominantly in non-erosive OLP, while other Candida species were predominate in erosive OLP. Non-Candida albicans isolates (C. glabrata, C. krusei) were resistant to the commonly used antifungals, clotrimazole and fluconazole. Candida infection is common in cases of OLP. We recommend antifungal sensitivity testing prior to antifungal therapy for the erosive form of OLP. 相似文献
88.
Cryptic promoter elements play a significant role in evolution of plant gene expression patterns and are prospective tools for creating gene expression systems in plants. In a previous report, a 452 bp promoter fragment designated as cryptic root-specific promoter (AY601849) was identified immediately upstream to T-DNA insertion, in the intergenic region between divergent genes SAHH1 and SHMT4, in T-DNA tagged mutant M57 of Arabidopsis thaliana. In silico analysis of 452 bp promoter revealed typical eukaryotic promoter architecture, presence of root-specific motifs and other cis-regulatory motifs responsible for the spatial and temporal expression. GUS expression driven by 452 bp in M57 was developmentally as well as light-regulated. The AT-rich 452 bp promoter does not show homology to any known sequences. The 452 bp promoter was further proved cryptic and detailed molecular characterization of the promoter carried out through serial 5′ and 3′ deletion analysis, by cloning the promoter fragments upstream to promoter-less GUS vector. A 279 bp fragment obtained by deleting 173 bp from 5′ end of 452 bp was capable of driving root-specific expression, similar to that of full-length promoter. Further, root tip-specific, root-specific and core-regulatory motifs for root-specific expression were identified at positions 173–227, 251–323 and 408–452 bp, respectively, from the 5′ end of 452 bp. The 452 bp promoter was equally functional in inverse orientation, hence bidirectional and symmetric. In heterologous systems, such as Brassica juncea and Oryza sativa, the promoter activity was not significant since GUS was not visually detected in transient assays. 相似文献
89.
Keith C. Weiser Bin Liu Gwenn M. Hansen Darlene Skapura Kathryn E. Hentges Sujatha Yarlagadda Herbert C. Morse III Monica J. Justice 《Mammalian genome》2007,18(10):709-722
AKXD recombinant inbred (RI) strains develop a variety of leukemias and lymphomas due to somatically acquired insertions of
retroviral DNA into the genome of hematopoetic cells that can mutate cellular proto-oncogenes and tumor suppressor genes.
We generated a new set of tumors from nine AKXD RI strains selected for their propensity to develop B-cell tumors, the most
common type of human hematopoietic cancers. We employed a PCR technique called viral insertion site amplification (VISA) to
rapidly isolate genomic sequence at the site of provirus insertion. Here we describe 550 VISA sequence tags (VSTs) that identify
74 common insertion sites (CISs), of which 21 have not been identified previously. Several suspected proto-oncogenes and tumor
suppressor genes lie near CISs, providing supportive evidence for their roles in cancer. Furthermore, numerous previously
uncharacterized genes lie near CISs, providing a pool of candidate disease genes for future research. Pathway analysis of
candidate genes identified several signaling pathways as common and powerful routes to blood cancer, including Notch, E-protein,
NFκB, and Ras signaling. Misregulation of several Notch signaling genes was confirmed by quantitative RT-PCR. Our data suggest
that analyses of insertional mutagenesis on a single genetic background are biased toward the identification of cooperating
mutations. This tumor collection represents the most comprehensive study of the genetics of B-cell leukemia and lymphoma development
in mice. We have deposited the VST sequences, CISs in a genome viewer, histopathology, and molecular tumor typing data in
a public web database called VISION (Viral Insertion Sites Identifying Oncogenes), which is located at .
Keith C. Weiser and Bin Liu are authors that contributed equally to this work. 相似文献
90.
Raynner RD Barboza Wedson de MS Souto José da S Mourão 《Journal of ethnobiology and ethnomedicine》2007,3(1):1-14