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41.
Methylobacteria are ubiquitous in the biosphere which are capable of growing on C1 compounds such as formate, formaldehyde, methanol and methylamine as well as on a wide range of multi-carbon growth substrates such as C2, C3 and C4 compounds due to the methylotrophic enzymes methanol dehydrogenase (MDH). MDH is performing these functions with the help of a key protein mxaF. Unfortunately, detailed structural analysis and homology modeling of mxaF is remains undefined. Hence, the objective of this research is the characterization and three dimensional modeling of mxaF protein from three different methylotrophs by using I-TASSER server. The predicted model were further optimize and validate by Profile 3D, Errat, Verifiy3-D and PROCHECK server. Predicted and best evaluated models have been successfully deposited to PMDB database with PMDB ID PM0077505, PM0077506 and PM0077507. Active site identification revealed 11, 13 and 14 putative functional site residues in respected models. It may play a major role during protein-protein, and protein-cofactor interactions. This study can provide us an ab-initio and detail information to understand the structure, mechanism of action and regulation of mxaF protein.  相似文献   
42.
A wheat endophytic bacterium (Pseudomonas aeruginosa PW09) was evaluated for its ability to trigger an induced systemic resistance response in cucumber against biotic and abiotic stresses. PW09 was applied to cucumber seeds, and the seedlings were subjected to Sclerotium rolfsii infection and NaCl (150 mm ). The role of PW09 was evaluated in alleviating the stresses by assessing plant mortality due to S. rolfsii infection and biomass accumulation under NaCl stress as well as at the physiological level through phenylpropanoid metabolism, antioxidant activities and proline accumulation. The endophyte reduced seedling mortality by 60% and increased biomass accumulation significantly under S. rolfsii (7%) and NaCl (18%) stresses, respectively, compared with endophyte‐untreated seedlings. Application of PW09 also induced higher accumulation of proline (1.3‐ and 1.4‐fold) and total phenolics (1.2‐ and 1.1‐fold) and activities of polyphenol oxidase (4.3‐ and 1.5‐fold), phenylalanine ammonia lyase (1.29‐ and 1.27‐fold) and superoxide dismutase (2.5‐ and 1.39‐fold) under S. rolfsii and NaCl stresses, indicating the ability of the wheat endophyte PW09 in alleviating both biotic and abiotic stresses in cucumber.  相似文献   
43.
Jatropha curcas L., a multipurpose shrub has acquired significant economic importance for its seed oil which can be converted to biodiesel, is emerging as an alternative to petro-diesel. The deoiled seed cake remains after oil extraction is toxic and cannot be used as a feed despite having best nutritional contents. No quantitative and qualitative differences were observed between toxic and non-toxic varieties of J. curcas except for phorbol esters content. Development of molecular marker will enable to differentiate non-toxic from toxic variety in a mixed population and also help in improvement of the species through marker assisted breeding programs. The present investigation was undertaken to characterize the toxic and non-toxic varieties at molecular level and to develop PCR based molecular markers for distinguishing non-toxic from toxic or vice versa. The polymorphic markers were successfully identified specific to non-toxic and toxic variety using RAPD and AFLP techniques. Totally 371 RAPD, 1,442 AFLP markers were analyzed and 56 (15.09%) RAPD, 238 (16.49%) AFLP markers were found specific to either of the varieties. Genetic similarity between non-toxic and toxic verity was found to be 0.92 by RAPD and 0.90 by AFLP fingerprinting. In the present study out of 12 microsatellite markers analyzed, seven markers were found polymorphic. Among these seven, jcms21 showed homozygous allele in the toxic variety. The study demonstrated that both RAPD and AFLP techniques were equally competitive in identifying polymorphic markers and differentiating both the varieties of J. curcas. Polymorphism of SSR markers prevailed between the varieties of J. curcas. These RAPD and AFLP identified markers will help in selective cultivation of specific variety and along with SSRs these markers can be exploited for further improvement of the species through breeding and Marker Assisted Selection (MAS).  相似文献   
44.
NAFLD (non-alcoholic fatty liver disease), associated with obesity and the cardiometabolic syndrome, is an important medical problem affecting up to 20% of western populations. Evidence indicates that mitochondrial dysfunction plays a critical role in NAFLD initiation and progression to the more serious condition of NASH (non-alcoholic steatohepatitis). Herein we hypothesize that mitochondrial defects induced by exposure to a HFD (high fat diet) contribute to a hypoxic state in liver and this is associated with increased protein modification by RNS (reactive nitrogen species). To test this concept, C57BL/6 mice were pair-fed a control diet and HFD containing 35% and 71% total calories (1 cal approximately 4.184 J) from fat respectively, for 8 or 16 weeks and liver hypoxia, mitochondrial bioenergetics, NO (nitric oxide)-dependent control of respiration, and 3-NT (3-nitrotyrosine), a marker of protein modification by RNS, were examined. Feeding a HFD for 16 weeks induced NASH-like pathology accompanied by elevated triacylglycerols, increased CYP2E1 (cytochrome P450 2E1) and iNOS (inducible nitric oxide synthase) protein, and significantly enhanced hypoxia in the pericentral region of the liver. Mitochondria from the HFD group showed increased sensitivity to NO-dependent inhibition of respiration compared with controls. In addition, accumulation of 3-NT paralleled the hypoxia gradient in vivo and 3-NT levels were increased in mitochondrial proteins. Liver mitochondria from mice fed the HFD for 16 weeks exhibited depressed state 3 respiration, uncoupled respiration, cytochrome c oxidase activity, and mitochondrial membrane potential. These findings indicate that chronic exposure to a HFD negatively affects the bioenergetics of liver mitochondria and this probably contributes to hypoxic stress and deleterious NO-dependent modification of mitochondrial proteins.  相似文献   
45.
Volatile aroma compounds are synthesized by wine yeast during wine fermentation. In this study the volatile aroma composition of two varieties of mango wine were determined to differentiate and characterize the wines. The wine was produced from the fruits of two varieties of mango cultivars namely Banginapalli and Alphonso. The volatile compounds formed in mango wine were analyzed by gas chromatography coupled with mass spectrometry (GC-MS). Thirty-two volatile compounds in wines were determined of which four were new and unidentified present in lower concentration. Apart from the ethanol (8.5 ± 0.28 and 7.2 ± 0.28% v/v), 1-propanol (54.11 ± 0.33 and 42.32 ± 0.57 mg/l), isobutyl alcohol (102 ± 1.57 and 115.14 ± 2.88 mg/l) and isoamyl alcohol (123 ± 2.88 and 108.40 ± 0.23 mg/1) were found to be the major flavouring higher alcohols in the mango wines produced from the fruits of Banginapalli and Alphonso respectively. Ethyl acetate (35 ± 0.57 and 30.42 ±1.15 mg/l) was the major ester component in both wines produced. Besides, other esters like ethyl octonoate, ethyl hexanoate and ethyl decanoate were also present in the wines. Cyclohexane methanol (1.45 ± 0.11 mg/l) was present only in wine made from Banginapalli and β-phenylethyl butanoate (0.62 ± 0.01 mg/1) was found only in Alphonso wine. The results demonstrate that the wine prepared from Banginapalli variety had better aroma composition and good taste than that from the Alphonso variety.  相似文献   
46.
47.
The baiting bag method was found to be useful for isolating antagonistic actinomycetes from terrestrial habitat. Out of total 110 actinomycetes isolated from rhizospheric and non-rhizospheric soil of Indo Gangetic Plains (IGP) of India, 9 isolates exhibited aggressive antagonism against Rhizoctonia solani, screened through dual culture, well diffusion and sealed plate technique. Maximum growth inhibition was recorded up to 50% under well diffusion (S. toxytricini vh22) and 52.6% in a direct confrontation (Actinomycetales bacterium vh41). Whereas maximum disease suppression (53.33%) under green house condition was achieved on seedling treated with S. tricolor vh85. Scanning electron microscopy of antagonists and pathogen interaction exhibited pore formation and hyphal degradation of test pathogen. Physiological and molecular characterization of selected isolates showed wide diversity and uncommon species has been encountered through the selective isolation technique.  相似文献   
48.
Mango peel is one of the major wastes from fruit processing industries, which poses considerable disposal problems and ultimately leads to environmental pollution. The objective of the current research was to determine the significant parameters on the production of polygalacturonase from mango peel which is a major industrial waste. Solid state culture conditions for polygalacturonase production by Fusarium moniliforme from dried mango peel powder were optimized by Taguchi’s L-18 orthogonal array experimental design methodology. Eight fungal metabolic influencing variables, viz. temperature, mango peel, inoculum, peptone, ammonium nitrate (NH4NO3), magnesium sulphate (MgSO4), zinc sulphate (ZnSO4) and potassium dihydrogen phosphate (KH2PO4) were selected to optimize polygalacturonase production. The optimized parameters composed of temperature (30°C), mango peel (6.5%, g, w/v), inoculum (8%, ml, v/v), peptone (1%, g, w/v), NH4NO3 (0.60%, g, w/v), MgSO4 (0.05%, g, w/v), ZnSO4 (0.06%, g, w/v) and KH2PO4 (0.4%, g, w/v). Based on the influence of interaction of fermentation components of fermentation, these could be classified as the least significant and the most significant at individual and interaction levels. The temperature, inoculum level, mango peel substrate and KH2PO4 showed maximum production impact at optimized conditions. From the optimized conditions the polygalacturonase activity was maximized to 43.2 U g−1.  相似文献   
49.
Systems biology approaches that are based on the genetics of gene expression have been fruitful in identifying genetic regulatory loci related to complex traits. We use microarray and genetic marker data from an F2 mouse intercross to examine the large-scale organization of the gene co-expression network in liver, and annotate several gene modules in terms of 22 physiological traits. We identify chromosomal loci (referred to as module quantitative trait loci, mQTL) that perturb the modules and describe a novel approach that integrates network properties with genetic marker information to model gene/trait relationships. Specifically, using the mQTL and the intramodular connectivity of a body weight–related module, we describe which factors determine the relationship between gene expression profiles and weight. Our approach results in the identification of genetic targets that influence gene modules (pathways) that are related to the clinical phenotypes of interest.  相似文献   
50.
The radio-protective ability of sesamol (SM) at various doses viz., 0, 10, 25, 40, 50, 70 and 100 mg/kg bw, administered intraperitoneally 30 min prior to 9.5 Gy whole-body γ-irradiation was studied in Swiss albino mice. Radiation toxicity and mortality were observed during a period of 30 days and the percentage mortality was calculated. SM pretreatment with 50 mg/kg bw was found to be the most effective dose in maintaining body weight and in reducing the percentage mortality, while 100 mg/kg bw was found to be more effective in maintaining the spleen index and in stimulation of endogenous spleen colony-forming units. Pretreatment with SM (50 mg/kg bw) in mice irradiated with 15 Gy significantly reduced dead, inflammatory, mitotic and goblet cells in irradiated jejunum. SM at 50 mg/kg bw also increased crypt cells, maintained villus height, and prevented mucosal erosion. Nuclear enlargement in epithelial cells was found less in SM-treated mice compared with the irradiated control. The radiation-induced decrease in endogenous antioxidant enzymes (GSH, GST, catalase) and the increase in lipid peroxidation were also reduced by pretreatment with SM [50 and 100 mg/kg bw] at all monitored post-irradiation intervals. There was no protection at a dose less than 25 mg/kg bw.  相似文献   
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