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Starch phosphorylation is an important biochemical aspect of plant starch metabolism as it influences the overall structure of the starch granule, and a prerequisite for its degradation. There is a growing interest on the isolation and characterization of α-glucan/glucan-like, water dikinases (GWDs) from plants, particularly agriculturally important crops, because GWD is known to catalyze starch phosphorylation both in leaves and different plant storage organs. In the present study, a 4,789-bp full-length cDNA encoding a GWD isoform was isolated from a commercially important Indian potato cultivar, Kufri Chipsona-1 by RT-PCR approach using tuber RNA. The predicted protein consisted of 1,463 amino acids having N-terminal 77-amino acid transit peptide, and 1,386-amino acid mature protein shorter by one amino acid as compared to the other mature GWDs from potato and tomato. The mature GWD showed 98 % sequence identity with the GWD isolated earlier from the potato cv. Desiree. Variations were found at 25 locations representing mostly non-conservative substitutions. The GWD represents a distinct isoform from potato, as revealed by sequence and phylogenetic analyses. Amino acid composition, segment-wise hydrophobic characters, predicted secondary structures were also analyzed and documented in this report. Broadly, the level of GWD expression as analyzed by semi-quantitative RT-PCR approach was found to be nearly uniform both in the mature tubers and leaves from most of the potato cultivars. By immunodetection technique, a band corresponding to ~155 kDa protein was detected only in the tuber protein extracts. The tuber starch-bound phosphorus content data showed minor variations between the potato cultivars.  相似文献   
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The clustered regularly interspaced short palindromic repeats (CRISPR)/CRISPR-associated protein 9 (Cas9) has been reported for precise genome modification in many plants. In the current study, we demonstrate a successful mutation in phytoene desaturase (RAS-PDS) of banana cv. Rasthali using the CRISPR/Cas9 system. Two PDS genes were isolated from Rasthali (RAS-PDS1 and RAS-PDS2), and their protein sequence analysis confirmed that both PDS comprises conserved motifs for enzyme activity. Phylogenetic analysis of RAS-PDS1 and RAS-PDS2 revealed a close evolutionary relationship with other monocot species. The tissue-specific expression profile of RAS-PDS1 and RAS-PDS2 in Rasthali suggested differential regulation of the genes. A single 19-bp guide RNA (gRNA) was designed to target the conserved region of these two RAS-PDS and transformed with Cas9 in embryogenic cell suspension (ECS) cultures of cv. Rasthali. Complete albino and variegated phenotype were observed among regenerated plantlets. DNA sequencing of 13 plants confirmed the indels with 59% mutation frequency in RAS-PDS, suggesting activation of the non-homologous end-joining (NHEJ) pathway. The majority of mutations were either insertion (1–5) or deletion (1–4) of nucleotides near to protospacer adjacent motif (PAM). These mutations have created stop codons in RAS-PDS sequences which suggest premature termination of RAS-PDS protein synthesis. The decreased chlorophyll and total carotenoid contents were detected in mutant lines that revealed the functional disruption of both RAS-PDS genes. Our results demonstrate that genome editing through CRISPR/Cas9 can be applied as an efficient tool for banana genome modification.  相似文献   
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Complexes of the type [M(apash)Cl] and [M(Hapash)(H2O)SO4], where M = Mn(II), Co(II), Ni(II), Cu(II) and Zn(II); Hapash = acetone p-amino acetophenone salicyloyl hydrazone have been synthesized and characterized by elemental analyses, molar conductance, magnetic moments, electronic, ESR and IR spectra, thermal studies (TGA & DTA) and X-ray diffraction studies. The ligand coordinates through two >C=N and a deprotonated enolate group in all the chloro complexes, whereas through two >C=N- and a >C=O group in all the sulfato complexes. The electronic spectra suggest a square planar geometry for Co(II), Ni(II) and Cu(II) chloride complexes and an octahedral geometry for the sulfate complexes. ESR data show an isotropic symmetry for [Cu(apash)Cl] and [Cu(Hapash)(H2O)SO4] in solid state. However, ESR spectra of both Cu(II) complexes indicate the presence of unpaired electron in d x2-y2. The X-ray diffraction parameters for [Co(apash)Cl] and [Cu(Hapash)(H2O)SO4] complexes correspond to a tetragonal and an orthorhombic crystal lattices, respectively. Thermal studies of [Co(apash)Cl] complex shows a multi-step decomposition pattern. Most of the complexes show better antifungal activity than the standard miconazole against a number of pathogenic fungi. The antibacterial activity of these complexes has been evaluated against E. coli and Clostridium sp. which shows a moderate activity.  相似文献   
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Human mitochondrial DNA (mtDNA) encodes a set of 37 genes which are essential structural and functional components of the electron transport chain. Variations in these genes have been implicated in a broad spectrum of diseases and are extensively reported in literature and various databases. In this study, we describe MitoLSDB, an integrated platform to catalogue disease association studies on mtDNA (http://mitolsdb.igib.res.in). The main goal of MitoLSDB is to provide a central platform for direct submissions of novel variants that can be curated by the Mitochondrial Research Community. MitoLSDB provides access to standardized and annotated data from literature and databases encompassing information from 5231 individuals, 675 populations and 27 phenotypes. This platform is developed using the Leiden Open (source) Variation Database (LOVD) software. MitoLSDB houses information on all 37 genes in each population amounting to 132397 variants, 5147 unique variants. For each variant its genomic location as per the Revised Cambridge Reference Sequence, codon and amino acid change for variations in protein-coding regions, frequency, disease/phenotype, population, reference and remarks are also listed. MitoLSDB curators have also reported errors documented in literature which includes 94 phantom mutations, 10 NUMTs, six documentation errors and one artefactual recombination. MitoLSDB is the largest repository of mtDNA variants systematically standardized and presented using the LOVD platform. We believe that this is a good starting resource to curate mtDNA variants and will facilitate direct submissions enhancing data coverage, annotation in context of pathogenesis and quality control by ensuring non-redundancy in reporting novel disease associated variants.  相似文献   
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Place prioritization for biodiversity content   总被引:5,自引:0,他引:5  
The prioritization of places on the basis of biodiversity content is part of any systematic biodiversity conservation planning process. The place prioritization procedure implemented in the ResNet software package is described. This procedure is primarily based on the principles of rarity and complementarity. Application of the procedure is demonstrated with two analyses, one data set consisting of the distributions of termite genera in Namibia, and the other consisting of the distributions of bird species in the Islas Malvinas/Falkland Islands. The attributes that data sets should have for the effective and reliable application of such procedures are discussed. The procedure used here is compared to some others that are also currently in use.  相似文献   
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The popularity of date palm (Phoenix dactylifera) fruit is increasing, therefore the demand for high-quality date palm fruit with less or no chemical treatment is the topic of interest for date producers and consumers. The quality of date palm fruit is much dependent on its postharvest handling and processing. For preventing the degradation and maintenance of the high quality of dates during the storage an appropriate harvest and post-harvest processes are required. The process should control the biotic and abiotic factors like insects, fungus, temperature, as well as handling and processing of dates. Therefore, in this work, we reviewed the literature related to the protection of date fruits during their post-harvest life. The commercially viable advance and updated techniques that can be used to avoid storage losses and problems while keeping fruit quality (nutritional, color, flavor, and texture) and microbial safety under optimal conditions are discussed.  相似文献   
50.
A simple, environmentally benign and highly proficient microwave assisted one-pot approach for the synthesis of antimicrobial spiropyrrolidine/thiapyrrolizidine oxindole derivatives is reported assembling two pharmacophoric moieties (1,3-indanedione and pyrrolidine/thiapyrrolizidine) in a single molecular framework via three-component 1,3-dipolar cycloaddition reaction of substituted isatin, sarcosine/1,3-thiazoles-4-carboxylic acid and Knoevenagel adduct (2-Cyano-3-phenyl-acrylic acid ethyl ester or 2-Benzylidene-malononitrile) in 2,2,2-trifluoroethanol as a reusable green solvent. Good functional group tolerance and broad scope of usable substrates are other prominent features of the present methodology with high degree of chemo-, regio- and stereoselectivity. The stereochemistry of synthesized compounds was confirmed by single crystal X-ray analysis. All the synthetic compounds were examined for their antimicrobial potential. The synthesized compounds having pyrrolothiazole moiety showed excellent activity against K. pneumoniae as compared to others and even more inhibitory activity than the mentioned drugs, i.e. compounds 6a (MIC = 0.09 μg/mL), 6b (MIC = 0.045 μg/mL), 6c (MIC = 0.005 μg/mL), 6d (MIC = 0.19 μg/mL). Additionally, compound 6c has shown better binding affinity against New Delhi Metallo-beta-Lactamase-1 (NDM-1) protein in computational docking studies.  相似文献   
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