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ALAM M.F. KHAN M.R. NURUZZAMAN M. PARVEZ S. SWARAZ A.M. ALAM I. AHSAN N. 《Journal of Zhejiang University. Science. B》2004,(4)
INTRODUCTIONAlthoughriceisanaturallyself-pollinatedcrop,strongheterosisisobservedintheirF1hybrids.HeterosisorhybridvigorismanifestedasimprovedperformanceforF1hybridsgeneratedbycrossingtwoinbredparents.Heterosiscanbedefinedquan-titativelyasanupwarddeviationofthemid-parent,basedonthemeanvaluesofthetwoparents(JohnsonandHutchinson,1993).Heterosismaybepositiveornegative.Dependinguponbreedingob-jectives,bothpositiveandnegativeheterosisareusefulforcropimprovement.Ingeneral,positiveheterosisisd… 相似文献
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Sheereen TARANNUM Zarina ARIF Khursheed ALAM 《Journal of Zhejiang University. Science. B》2013,14(1):40-46
Peroxynitrite(ONOO) is a powerful oxidant and nitrosative agent and has in vivo existence.The half life of ONOO at physiological pH is less than 1 s.It can react with nucleic acids,proteins,lipoproteins,saccharides,cardiolipin,etc.,and can modify their native structures.Action of ONOO,synthesized in the authors’ laboratory by a rapid quenched flow process,on structural changes of commercially available RNA was studied by ultraviolet(UV),fluorescence,and agarose gel electrophoresis.Compared to native RNA,the ONOO-modified RNA showed hyperchromicity at 260 nm.Furthermore,the ethidium bromide(EtBr) assisted emission intensities of ONOO-modified RNA samples were found to be lower than the emission intensity of native RNA-EtBr complex.Agarose gel electrophoresis of ONOO-modified RNA showed a gradual decrease in band intensities compared to native RNA,an observation clearly due to the poor intercalation of EtBr with ONOO-modified RNA.Native and ONOO-modified RNA samples were used as an antigen to detect autoantibodies in sera of patients with clinically defined breast cancer.Both direct binding and inhibition enzyme-linked immunosorbent assay(ELISA) confirmed the prevalence of native and 0.8 mmol/L ONOO-modified RNA specific autoantibodies in breast cancer patients.Moreover,the progressive retardation in the mobility of immune complexes formed with native or 0.8 mmol/L ONOO-modified RNA and affinity purified immunoglobulin G(IgG) from sera of breast cancer patients supports the findings of the direct binding and inhibition ELISAs.The peroxynitrite treatment to RNA at a higher concentration appears to have damaged or destroyed the typical epitopes on RNA and thus there was a sharp decrease in autoantibodies binding to 1.4 mmol/L ONOO-modified RNA.It may be interpreted that cellular nitrosative stress can modify and confer immunogenicity on RNA molecules.Higher concentrations of nitrogen reactive species can be detrimental to RNA.However,the emergence of native as well as 0.8 mmol/L ONOO-modified RNA as a novel antigen/substrate for autoantibodies in breast cancer patients indicates that,in future,these molecules might find a place on the panel of antigens for early diagnosis of breast cancer. 相似文献
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Pakistani wheat varieties are grown over a wide agro-climatic range and as such are anticipated to exhibit yield and quality differences. It is therefore necessary to investigate the nutritional status of wheat varieties in terms of biochemical and physiochemical characteristics available for food and nutritional purposes in Pakistan. The result shows that wheat grains of different varieties contain a net protein level of 9.15%～10.27%, 2.15%～2.55% total fats, 1.72%～1.85% dietary fibers, 77.65×10-6～84.25×10-6 of potassium and 7.70×10-6～35.90×10-6 of sodium ions concentration, 0.24×10-6～0.84×10-6 of phosphorus, 1.44%～2.10% ash, 31.108～43.602 g of thousand grain mass (TGM) and 8.38%～9.67% moisture contents. This study is significant in providing an opportunity to explore the available wheat varieties and to further improve their nutritional excellence and also essential for setting nutritional regulations for domestic and export purposes. 相似文献
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This paper considers the relationship between knowledge production and primary education policy making in Bangladesh. It investigates the form of discussions and dialogues that have taken place between policy makers and researchers and considers how these have shaped the nature of the evidence policy makers have used in different periods. The paper also attempts to assess the implications of the shifting forms of relationship between policy and knowledge production for strategies to introduce universal primary education and improve its quality. The paper itself is an example of some of the themes it examines. It has emerged out of discussions taking place in the research committee of the Bangladesh Directorate of Primary Education (DPE) and Primary and Mass Education Division (PMED). (See Figure 1.) This committee, established as part of the DFID funded ESTEEM project [1], brings together officials from DPE and PMED with education researchers from Bangladesh's universities and consultants appointed by ESTEEM. An aspect of the work of the research committee has been to consider what kinds of knowledge are useful in the implementation of policy. In summary we argue that, except for an early period after the War of Independence, there has been little open dialogue between researchers and policy makers in Bangladesh. Policy has been much more closely shaped by the changing forms and values of educational administration in central government and in large NGOs than by 'scientific' forms of research and knowledge production or by the debates these might provoke. Research and education policy development have been the preserve of elite groups closely connected to central government. Very little research has been undertaken independent of government or commissions from large NGOs. However, in different periods researchers have participated in policy formation in different ways and there are indications in the present period that the views of researchers and policy makers are beginning to diverge somewhat with some more critical commentary being published. We map the history of these changing forms of participation in order to reveal aspects of the context in which successive policies have been formed. 相似文献
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The genetic basis of heterosis was studied through mid-parent, standard variety and better parent for 11 quantitative traits in 17 parental lines and their 10 selected hybrids in rice (Oryza sativa L.). The characters were plant height, days to flag leaf initiation, days to first panicle initiation, days to 100% flowering, panicle length, flag leaf length, days to maturity, number of fertile spikelet/panicle, number of effective tillers/hill, grain yield/10-hill, and 1000-grain weight. In general the hybrids performed significantly better than the respective parents. Significant heterosis was observed for most of the studied characters. Among the 10 hybrids, four hybrids viz., 17A×45R, 25A×37R, 27A×39R, 31A×47R, and 35A×47R showed highest heterosis in 10-hill grain yield/10-hill. Inbreeding depression of F2 progeny was also studied for 11 characters of 10 hybrids. Both positive and negative inbreeding depression were found in many crosses for the studied characters, but none was found significant. Selection of good parents was found to be the most important for developing high yielding hybrid rice varieties. 相似文献
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