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11.
Beta-urogastrone also known as human epidermal growth factor is a key member of epidermal growth factor family having role in cell proliferation and differentiation in vivo as well as in vitro. Human epidermal growth factor gene has been isolated from different tissues but the method of isolation is technically difficult and complicated as it deals with biopsies. Here we isolated mature partial human epidermal growth factor gene from Huh-7 cell line, amplified and abridged toward mature coding region with three steps PCR, sequenced for homology with wild type human epidermal growth factor gene, inbuilt with sites of interest and cloned in Pichia pastoris for expression study. Isolated mature human epidermal growth factor gene from Huh-7 cell line showed 100 % sequence homology to wild type human epidermal growth factor gene and gives the native expression for human epidermal growth factor peptide. In this study we report that Huh-7 cell line is an easy source for the particular gene of human epidermal growth factor isolation and we are also suggesting P. pastoris is an expression system to produce recombinant human epidermal growth factor of the therapeutic importance resembling to the natural human system.  相似文献   
12.
Somatic embryos differentiated from hypocotyl explant in cotton (Gossypium hirsutum L.) exhibited very divergent morphologies. Six different types of somatic embryos based on cotyledon development were observed. The growth hormones (2,4-dichlorophenoxyacetic acid and kinetin) used in induction and maintenance media did not affect embryo rooting and germination. The 95 % conversion of normal embryos (with two cotyledons) was achieved, while an overall conversion was only 38 %. Horn shaped embryos failed to exhibit shoot growth. Poorly developed apical meristems were responsible for lower conversion percentages in some of embryo classes. However, regenerated plants phenotypically resembled to seed grown control plants regardless of somatic embryo morphology.  相似文献   
13.
RNA interference (RNAi) is commonly used to produce virus tolerant transgenic plants. The objective of the current study was to generate transgenic sugarcane plants expressing a short hairpin RNAs (shRNA) targeting the coat protein (CP) gene of sugarcane mosaic virus (SCMV). Based on multiple sequence alignment, including genomic sequences of four SCMV strains, a conserved region of ~ 456 bp coat protein (CP) gene was selected as target gene and amplified through polymerase chain reaction (PCR). Subsequently, siRNAs2 and siRNA4 were engineered as stable short hairpin (shRNA) transgenes of 110 bp with stem and loop sequences derived from microRNA (sof-MIR168a; an active regulatory miRNA in sugarcane). These transgenes were cloned in independent RNAi constructs under the control of the polyubiquitin promoter. The RNAi constructs were delivered into two sugarcane cultivars ‘SPF-234 and NSG-311 in independent experiments using particle bombardment. Molecular identification through PCR and Southern blot revealed anti-SCMV positive transgenic lines. Upon mechanical inoculation of transgenic and non-transgenic sugarcane lines with SCMV, the degree of resistance was found variable among the two sugarcane cultivars. For sugarcane cultivar NSG-311, the mRNA expression of the CP–SCMV was reduced to 10% in shRNA2-transgenic lines and 80% in shRNA4-transgenic lines. In sugarcane cultivar SPF-234, the mRNA expression of the CP–SCMV was reduced to 20% in shRNA2-transgenic lines and 90% in shRNA4 transgenic lines, revealing that transgenic plants expressing shRNA4 were almost immune to SCMV infection.  相似文献   
14.
Conditions were established for the optimum transient expression of beta-glucuronidase and neomycin phosphotransferase II genes introduced into zygotic embryos of chickpea (Cicer arietinum L. 6153 and CM72) by accelerated tungsten particles. Plasmid DNA at a concentration of 12 microgram per milligram of tungsten particles when accelerated with an inflow of helium gas at 60 kilogram per square centimeter through a distance of 24 centimeter in a chamber maintained at a negative pressure of 71.12 centimeter of mercury, resulted in optimal transient expression of the beta-glucuronidase gene in chickpea embryos. However, the expression of the marker genes was 20-40% higher under a cauliflower mosaic virus promoter in comparison to the Win6 and actin promoters. When Agrobacterium tumefaciens was used to transfer marker genes into zygotic embryos and the resultant plants were analysed for activity of the beta-glucuronidase and neomycin phosphotransferase II genes, both of these genes were expressed in tumorous tissues. When a disarmed strain of Agrobacterium was used, normal shoots were regenerated in which the lower parts showed expression of both genes at a frequency of 20%. This revised version was published online in June 2006 with corrections to the Cover Date.  相似文献   
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16.
Ahmed  M.  Akhtar  S.  Fanglu  M.  Hasan  M. M.  Shahid  A. A.  Yanang  X.  Sarwar  M. B.  Rao  A. Q.  Husnain  T.  Wang  X. 《Russian Journal of Plant Physiology》2019,66(1):41-49
Russian Journal of Plant Physiology - Cotton (Gossypium hirsutum L.) fiber initiation from ovule epidermal cells happen from 0 to 5 DPA, invertase (INV) and sucrose synthase (SuSy) are...  相似文献   
17.
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   
18.
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   
19.
The study aims to use cholesterol (Chol) + DOTAP liposome (CD liposome) based human vascular endothelial growth factor-165 (VEGF(165)) gene transfer into skeletal myoblasts (SkMs) for treatment of acute hind limb ischaemia in a rabbit model. The feasibility and efficacy of CD liposome mediated gene transfer with rabbit SkMs were characterized using plasmid carrying enhanced green fluorescent protein (pEGFP) and assessed by flow cytometry. After optimization, SkMs were transfected with CD lipoplexes carrying plasmid-VEGF(165) (CD-pVEGF(165)) and transplanted into rabbit ischaemic limb. Animals were randomized to receive intramuscular injection of Medium199 (M199; group 1), non-transfected SkM (group 2) or CD-pVEGF(165) transfected SkM (group 3). Flow cytometry revealed that up to 16% rabbit SkMs were successfully transfected with pEGFP. Based on the optimized transfection condition, transfected rabbit SkM expressed VEGF(165) up to day 18 with peak at day 2. SkMs were observed in all cell-transplanted groups, as visualized with 6-diamidino-2-phenylindole and bromodeoxyuridine. Angiographic blood vessel score revealed increased collateral vessel development in group 3 (39.7 +/- 2.0) compared with group 2 (21.6 +/- 1.1%, P < 0.001) and group 1 (16.9 +/- 1.1%, P < 0.001). Immunostaining for CD31 showed significantly increased capillary density in group 3 (14.88 +/- 0.9) compared with group 2 (8.5 +/- 0.49, P < 0.001) and group 1 (5.69 +/- 0.3, P < 0.001). Improved blood flow (ml/min./g) was achieved in animal group 3 (0.173 +/- 0.04) as compared with animal group 2 (0.122 +/- 0.016; P= 0.047) and group 1 (0.062 +/- 0.012; P < 0.001). In conclusion, CD liposome mediated VEGF(165) gene transfer with SkMs effectively induced neovascularization in the ischaemic hind limb and may serve as a safe and new therapeutic modality for the repair of acute ischaemic limb disease.  相似文献   
20.
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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