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21.
S Riazuddin  A Nasim 《Génome》1989,31(2):1042-1045
Conditions in developing countries are nowhere near what they should be to reap the benefits of modern biotechnology. Be that as it may, there are possibilities in which intelligent thinking and rational planning by the people concerned, combined with input from international agencies and national centres of excellence, can lead to potential economic gains. One possibility is the establishment of collaborative research on a regional basis to tackle common problems and to train each other's manpower in acquired skills. Similarity of circumstances would make these programmes more relevant and cost effective. To ensure the success of joint programmes in the local setting, foreign input in the form of finances, provision of critical laboratory materials, and expert advice in the selection of technically solvable problems becomes inevitable. Thus participation by the developed-country agencies and laboratories in the developing countries presents a purposeful pooling of efforts that will sow the seeds for sustainable development of the developing world. Given that, new technology would prove a boon and a blessing for humanity in general and for the developing world in particular.  相似文献   
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The 949 bp promoter fragment upstream from the translation initiation site of the GUSP gene encoding a universal stress protein was isolated from the genomic DNA of Gossypium arboreum. Some putative cis-acting elements involved in stress responses including E-box, ABRE, DPBF-box, and MYB-core elements were found in the promoter region. In an Agrobacterium-mediated transient expression assay, strong activation of the GUSP full promoter region occurred in tobacco leaves following dehydration, abscisic acid, salt, heavy metal, gibberellic acid and dark treatments. Deletion analysis of the promoter revealed that the dehydration, abscisic acid and salt responses were affected by the deletion between −208 and −949 bp and showed 2–4-fold induction. However, in response to dark, gibberellic acid and heavy metals the induction was only 2-fold. These findings further our understanding of the regulation of GUSP expression. This is an important study as no report of this universal stress protein promoter is available in literature.  相似文献   
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BSND encodes barttin, an accessory subunit of renal and inner ear chloride channels. To date, all mutations of BSND have been shown to cause Bartter syndrome type IV, characterized by significant renal abnormalities and deafness. We identified a BSND mutation (p.I12T) in four kindreds segregating nonsyndromic deafness linked to a 4.04-cM interval on chromosome 1p32.3. The functional consequences of p.I12T differ from BSND mutations that cause renal failure and deafness in Bartter syndrome type IV. p.I12T leaves chloride channel function unaffected and only interferes with chaperone function of barttin in intracellular trafficking. This study provides functional data implicating a hypomorphic allele of BSND as a cause of apparent nonsyndromic deafness. We demonstrate that BSND mutations with different functional consequences are the basis for either syndromic or nonsyndromic deafness.  相似文献   
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Nucleotide sequence encoding the truncated insecticidal Cry1Ca1 protein from Bacillus thuringiensis was extensively modified based on the codon usage of rice genes. The overall G + C contents of the synthetic cry1Ca1 coding sequence were raised to 65% with an additional bias of enriching for G and C ending codons as preferred by monocots. The synthetic gene was introduced into the Chinese japonica variety, Xiushui 11, by Agrobacterium-mediated transformation. Transgenic rice plants harboring this gene were highly resistant to Chilo suppressalis and Spodoptera litura larvae as revealed by insect bioassays. High levels of Cry1Ca1 protein were obtained in the leaves of transgenic rice, which were effective in achieving 100% mortality of S. litura and C. suppressalis larvae. The levels of Cry1Ca1 expression in the leaves of these transgenic plants were up to 0.34% of the total soluble proteins. The larvae of C. suppressalis and S. litura could consume a maximum of 1.89  and 4.89 mm2 of transgenic leaf area whereas the consumption of non-transgenic leaves by these larvae was significantly higher; 58.33 and 61.22 mm2, respectively. Analysis of R1 transgenic plants indicated that the cry1Ca1 was inherited by the progeny plants and provided complete protection against C. suppressalis and S. litura larvae.  相似文献   
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Heat‐shock proteins (HSP) are molecular chaperones for protein molecules. These proteins play an important role in protein–protein interactions such as, folding and assisting in the establishment of proper protein conformation and prevention of unwanted protein aggregation. A small HSP gene GHSP26 present in Gossypium arboreum responds to dehydration. In the present study, an attempt was made to overcome the problem of drought stress in cotton. A cDNA of GHSP26 was isolated from G. arboreum, cloned in plant expression vector, pCAMBIA‐1301 driven by the cauliflower mosaic virus 35S promoter and introduced into Gossypium hirsutum. The integration and expression studies of putative transgenic plants were performed through GUS assay; PCR from genomic DNA, and quantitative real‐time PCR analysis. Transgenic cotton plants showed an enhanced drought tolerance, suggesting that GHSP26 may play a role in plant responsiveness to drought. © 2009 American Institute of Chemical Engineers Biotechnol. Prog., 2010  相似文献   
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An efficient protocol forin vitro micropropagation of seven indica rice varieties was developed from meristem culture. Meristem (leaf base) was isolated from different age of seedlings and cultured on MS medium without hormones and supplemented with different concentrations of NAA and BAP. Regeneration of plantlets from meristem was observed within five days of culture. The meristem isolated from 4-day old seedlings gave highest regeneration on hormone free MS medium. Histological study of meristem (leaf base) from 4-day old seedlings confirmed the presence of meristematic cells. Regenerated plants were multiplied on MS medium supplemented with 0.05 mg/L NAA and 5 mg/L BAP. An average of five plants were obtained from single regenerated meristem. The plants regenerated from meristem showed morphological uniformity.  相似文献   
30.
Properties of 3-methyladenine-DNA glycosylase from Escherichia coli.   总被引:21,自引:0,他引:21  
S Riazuddin  T Lindahl 《Biochemistry》1978,17(11):2110-2118
An Escherichia coli enzyme that releases 3-methyladenine and 3-ethyladenine in free form from alkylated DNA has been purified 2800-fold in 7% yield. The enzyme does not liberate several other alkylation products from DNA, including 7-methylguanine,O6-methylguanine, 7-methyladenine, N6-methyladenine, 7-ethylguanine, O6-ethylguanine, and the arylalkylated purine derivatives obtained by treatment of DNA with 7-bromomethyl-12-methylbenz[a]anthracene. The reaction of the enzyme with alkylated DNA leads to the introduction of apurinic sites but no chain breaks (less than one incision per ten apurinic sites), and there is no detectable nuclease activity with native DNA, depurinated DNA, ultraviolet-irradiated DNA, or X-irradiated DNA as potential substrates. The enzyme is termed 3-methyladenine-DNA glycosylase. It is a small protein, Mr = 19 000, that does not require divalent metal ions, phosphate, or other cofactors in order to cleave base-sugar bonds in alkylated DNA.  相似文献   
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