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21.
Cartilaginous fishes represent the living group of jawed vertebrates that diverged from the common ancestor of human and teleost fish lineages about 530 million years ago. We generated approximately 1.4x genome sequence coverage for a cartilaginous fish, the elephant shark (Callorhinchus milii), and compared this genome with the human genome to identify conserved noncoding elements (CNEs). The elephant shark sequence revealed twice as many CNEs as were identified by whole-genome comparisons between teleost fishes and human. The ancient vertebrate-specific CNEs in the elephant shark and human genomes are likely to play key regulatory roles in vertebrate gene expression.  相似文献   
22.
Sharma RS  Mishra V  Singh R  Seth N  Babu CR 《Fitoterapia》2008,79(7-8):589-591
Extracts of roots of Rumex nepalensis, Berberis aristata, Arnebia benthamii, bark of Taxus wallichiana, Juglans regia and petals of Jacquinia ruscifolia were tested for their antifungal activity against twelve different fungal pathogens. Ethanolic extracts of R. nepalensis and J. ruscifolia extracts showed a broad spectrum of activity.  相似文献   
23.
Seed priming is a commercially applied technique for improving seed vigor under variable field conditions. The present study was carried out to optimize the methods (direct: soaking in water 1:1 W/V and indirect: preconditioning under high RH ≥ 85%) and duration (hours)of hydro-priming, attempting to correlate the critical seed water content with priming-induced metabolic-restart in dry mungbean (Vigna radiata L.)seeds. Although the rate of water absorption and the amount of water absorbed was more by direct compared to the indirect imbibition method, the priming-induced germination responses were identical after 6hof priming treatment. The seed water content absorbed during this period was crucial for initiating the chain of biochemical events, required for early synchronized germination in primed seeds which was evident by improved membrane permeability, high activity of catalase and superoxide dismutase, and more integrated chloroplast and mitochondria in primed seeds. We demonstrate that the critical water content, required for priming-induced benefits for germination vigor, is a relative unit with respect to the duration of priming and the rate of water absorption. Seed priming is a co-ordinately regulated mechanism for controlling germination capacity of seeds by modifying the permeability characteristics of biological membranes and enzyme activity. This study helps to enhance our understanding on the potential of seed priming for synchronized germination and early seedling establishment in the field and beneficial for the resource poor farming community for better return of their limited financial/farm resources under variable environmental/field conditions.  相似文献   
24.
Zinc (Zn) fertilization is important for Zn crop biofortification as well as increasing yields, thus proper Zn recommendations for soil application is needed for Zn deficient soils. The effectiveness of Zn applications was evaluated in different combinations of rates (2.5, 5.0, 7.5, and 10.0?kg?ha?1 per year) and frequencies (initial, alternate, and every year) in rice (Oriza sativa L.) – wheat (Triticum aestivum L.) cropping system in a Zn-deficient upland calcareous soil in the fourth year. Zn applications to rice at 7.5 and 10?kg?ha?1 of alternate year and 5.0 to 10?kg?ha?1 of every year had the highest rice equivalent yield as compared to no-Zn treatment. Hence, Zn application to rice at 7.5?kg?ha?1 at alternate years is the lowest rate at which highest rice equivalent yield of rice-wheat cropping system can be obtained.  相似文献   
25.
26.
Rethinking organic aerosols: semivolatile emissions and photochemical aging   总被引:4,自引:0,他引:4  
Most primary organic-particulate emissions are semivolatile; thus, they partially evaporate with atmospheric dilution, creating substantial amounts of low-volatility gas-phase material. Laboratory experiments show that photo-oxidation of diesel emissions rapidly generates organic aerosol, greatly exceeding the contribution from known secondary organic-aerosol precursors. We attribute this unexplained secondary organic-aerosol production to the oxidation of low-volatility gas-phase species. Accounting for partitioning and photochemical processing of primary emissions creates a more regionally distributed aerosol and brings model predictions into better agreement with observations. Controlling organic particulate-matter concentrations will require substantial changes in the approaches that are currently used to measure and regulate emissions.  相似文献   
27.
Jamwal  R.  Sharma  P. L.  Verma  S. C.  Chandel  R. S.  Sharma  Nidhi 《Phytoparasitica》2021,49(4):589-601
Phytoparasitica - In order to enhance the ecofriendly management of Tuta absoluta (Meyrick) (Lepidoptera: Gelechiidae), we studied the demographics and functional response of Blaptostethus...  相似文献   
28.
The present study investigates the effect of in vivo administration of alcoholic extract of Tinospora cordifolia whole plant (ALTC) on the proliferation and myeloid differentiation of bone marrow hematopoietic precursor cells in mice bearing a transplantable T cell lymphoma of spontaneous origin designated as Dalton's lymphoma (DL). BMC obtained from ALTC administered DL-bearing mice showed an enhanced BMC proliferation and colony forming ability in vitro in response to L929 conditioned medium as a source of colony stimulating factor (CSF). The number of granulocyte-macrophages colony (CFU-GM) was predominantly higher in the cultures of BMC obtained from ALTC administered mice as compared to mice injected with PBS alone. An increase in the count of bone marrow derived macrophages (BMDM) from ALTC administered mice was also observed along with an increase in the count of tumor associated macrophages. The BMDM obtained from ALTC administered mice showed an enhanced response to signal of LPS for activation to produce IL-1 and TNF. This study indicates that the T. cordifolia can influence the myeloid differentiation of bone marrow progenitor cells and the recruitment of macrophages in response to tumor growth in situ.  相似文献   
29.
This study is aimed at ascertaining the chemical partitioning ofCu, Zn, Pb, Ni, Cr and Cd in sewage sludge and agricultural soils repeatedly amended with sludge. The operationally determined speciation was investigated by using selective five steps sequential extraction method for partitioning these metals into different chemicalforms, likely to be released in solution under various environmental conditions. It provides qualitative evidence regarding the form of the association of metals and indirectly of their bioavailability. It can help to explain the process by which metals are eliminated from sewagesludge and also indicate the impact of the use of sludge on agriculturalsoils, as amendments. Data obtained by extraction procedure showed different metal distribution trend among the fractions in sewage sludgeand sludge-amended soils. Comparison of distribution pattern of metals in sludge and sludge-applied soils shows that there is possible redistribution of metals among the different phases. The sum of the metal content in the fractions compared well with the total metal content in sewage sludge, the ratios averaging 1.02, 1.04, 1.07, 0.94, 1.06, and 1.12 for Cu, Zn, Pb, Ni, Cr, and Cd, respectively. The metal recovery efficiency in sludge-amended soils was found to be: 108±6%, 102±5%, 115±8%, 111±4%, 104±7%and 124±28% for Cu, Zn, Pb, Ni, Cr and Cd, respectively.  相似文献   
30.
Boerhavia diffusa is extensively used in herbal medicines as well as in the Ayurvedic system, because it contains a set of clinically important compounds. In the present study, the genetic variability in Boerhavia diffusa between accessions of different geographical origin within the Indian territory is assessed through random amplified polymorphic DNA (RAPD) markers. Twenty-eight accessions of Boerhavia were screened with eighteen primers of which nine were found to be the most informative. The degree of polymorphism was found to be high in accessions collected from different places of Uttar Pradesh (Set II) in comparison to other states of India (Set I). A relatively lower level of polymorphism was recorded in accessions collected from diverse locations around Lucknow (Set III). Accessions from neighbouring geographical regions exhibited more similarity than those from distant regions (as revealed by the set I analysis). Certain diagnostic markers may be correlated with morphological character(s) such as plant type. BDL appeared most distinct and divergent from the rest of the accessions and the BDJ plant in set II also showed least similarity estimate. Fragments of 5.62 Kb and 4.47 Kb with primer GN59 was found to be unique for BDP and BD2 having ovate leaf character, whereas ovoid leaf genotype exhibited 0.79 Kb (GN34 primer) fragment. Similarly a unique band type (0.35 Kb) with primer GN83 was present in BDL and BD1 that share light pink flower. Jaccard's, and Nei and Li similarity coefficient values amongst the accessions were in the range of 0.22 to 0.89 and 0.33 to 0.93, respectively. Association of RAPD markers with the leaf characteristics, flower colour as well as with geographical locations has been made. This shows that RAPD markers are also useful for the study of genetic structure of Boerhavia populations.  相似文献   
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