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排序方式: 共有407条查询结果,搜索用时 15 毫秒
111.
Ajay Kumar Gautam Mona Kant Yogita Thakur 《Archives Of Phytopathology And Plant Protection》2013,46(6):627-635
A systemic study of fungal endophytes associated with different plant parts of Cannabis sativa and their antifungal activity was investigated in the present study. A total of 281 plant segments, including 91 leaves, 93 stem and 97 petioles samples, were screened for the isolation of endophytic fungi. Totally, 212 (77.65%) segments were found colonised by different fungi. Highest colonisation frequency were observed in stem parts (84.94%), then leaves (82.41%) and lowest 59.79% in petiole. Total eight fungal genera belonging to 12 species were isolated. Aspergillus is recorded as the most frequently occurring genera with three species Aspergillus niger, Aspergillus flavus and Aspergillus nidulans followed by Penicillium with two species Penicillium chrysogenum and Penicillium citrinum, while Phoma, Rhizopus, Colletotrichum, Cladosporium and Curvularia with single species. The antifungal potential of A. niger and A. flavus – two most frequently isolated endophytic fungi – was evaluated against two common plant pathogen, Colletotrichum gloeosporioides and Curvularia lunata. Different plant and fungal extracts individually and in combinations showed variations in antifungal activity against both the pathogens. The primary results obtained on antifungal activity of endophytes show their possible role in plant defence mechanism but it is a preliminary approach and more extensive research is still required. 相似文献
112.
113.
Anne van der Kant Sébastien Derégnaucourt Manfred Gahr Annemie Van der Linden Colline Poirier 《PloS one》2013,8(4)
Vocal learning in songbirds and humans occurs by imitation of adult vocalizations. In both groups, vocal learning includes a perceptual phase during which juveniles birds and infants memorize adult vocalizations. Despite intensive research, the neural mechanisms supporting this auditory memory are still poorly understood. The present functional MRI study demonstrates that in adult zebra finches, the right auditory midbrain nucleus responds selectively to the copied vocalizations. The selective signal is distinct from selectivity for the bird''s own song and does not simply reflect acoustic differences between the stimuli. Furthermore, the amplitude of the selective signal is positively correlated with the strength of vocal learning, measured by the amount of song that experimental birds copied from the adult model. These results indicate that early sensory experience can generate a long-lasting memory trace in the auditory midbrain of songbirds that may support song learning. 相似文献
114.
Broilers and broiler meat products are highly contaminated with extended spectrum beta-lactamase (ESBL) or plasmid-mediated AmpC beta-lactamase producing Escherichia coli and are considered to be a source for human infections. Both horizontal and vertical transmission might play a role in the presence of these strains in broilers. As not much is known about the presence of these strains in the whole production pyramid, the epidemiology of ESBL/AmpC-producing E. coli in the Dutch broiler production pyramid was examined. Cloacal swabs of Grandparent stock (GPS) birds (one−/two-days (breed A and B), 18 and 31 weeks old (breed A)), one-day old Parent stock birds (breed A and B) and broiler chickens of increasing age (breed A) were selectively cultured to detect ESBL/AmpC-producing isolates. ESBL/AmpC-producing isolates were found at all levels in the broiler production pyramid in both broiler breeds examined. Prevalence was already relatively high at the top of the broiler production pyramid. At broiler farms ESBL/AmpC producing E. coli were still present in the environment of the poultry house after cleaning and disinfection. Feed samples taken in the poultry house also became contaminated with ESBL/AmpC producing E. coli after one or more production weeks. The prevalence of ESBL/AmpC-positive birds at broiler farms increased within the first week from 0–24% to 96–100% independent of the use of antibiotics and stayed 100% until slaughter. In GPS breed A, prevalence at 2 days, 18 weeks and 31 weeks stayed below 50% except when beta-lactam antibiotics were administered. In that case prevalence increased to 100%. Interventions minimizing ESBL/AmpC contamination in broilers should focus on preventing horizontal and vertical spread, especially in relation to broiler production farms. 相似文献
115.
Maartje Willeboordse Donna L. C. M. van den Bersselaar Kim D. G. van de Kant Jean W. M. Muris Onno C. P. van Schayck Edward Dompeling 《PloS one》2013,8(10)
Objective
Obesity has been identified as a risk factor for asthma in children. However, in the Netherlands, the obesity prevalence is rising while the asthma prevalence in children is stabilising. The aim of this study is to clarify the association between asthma and Body Mass Index (BMI) in children and whether this association is influenced by sex.Study Design
Parents of 39,316 children (6-16 years) in the south of the Netherlands were invited to complete an online questionnaire on respiratory symptoms, anthropometric variables and several potential confounding factors for asthma and obesity (including sex, birth weight and breastfeeding). Data was analysed by multivariable logistic regression models and an ordinal regression model.Results
The response rate was 24% (n boys= 4,743, n girls= 4,529). The prevalence of asthma, overweight and obesity was 8%, 15% and 2% respectively. Body mass index - standard deviation Score (BMI-SDS) was related to current asthma (adjusted OR: 1.29; 95%CI: 1.14-1.45, p≤0.001). When stratified for sex, asthma and BMI-SDS were only related in girls (Girls: adjusted OR: 1.31; 95%CI: 1.13-1.51, p≤0.001. Boys: adjusted OR: 1.01; 95%CI: 0.91-1.14, p=0.72).Conclusions
The positive association between BMI-SDS and asthma is only present in girls, not boys. Future studies into obesity and asthma should correct for sex in their analyses. 相似文献116.
S.N. Suryawanshi Avinash Tiwari Santosh Kumar Rahul Shivahare Monika Mittal Padam Kant Suman Gupta 《Bioorganic & medicinal chemistry letters》2013,23(10):2925-2928
A novel series of triazole integrated phenyl heteroterpenoids have been synthesized and screened for their in vitro activity against intracellular amastigote form of Leishmania donovani. Among all tested compounds, compound 3a was found to be the most active with IC50 6.4 μM and better selectivity index (SI) 18 as compared to reference drugs, miltefosine and miconazole. When evaluated in vivo in L. donovani/hamster model, 3a has exhibited 79 ± 11% inhibition of parasite multiplication at 50 mg kg?1 × 5 days on day 7 post treatment. 相似文献
117.
LMP1 association with CD63 in endosomes and secretion via exosomes limits constitutive NF-κB activation 总被引:1,自引:0,他引:1
Verweij FJ van Eijndhoven MA Hopmans ES Vendrig T Wurdinger T Cahir-McFarland E Kieff E Geerts D van der Kant R Neefjes J Middeldorp JM Pegtel DM 《The EMBO journal》2011,30(11):2115-2129
The ubiquitous Epstein Barr virus (EBV) exploits human B-cell development to establish a persistent infection in ~90% of the world population. Constitutive activation of NF-κB by the viral oncogene latent membrane protein 1 (LMP1) has an important role in persistence, but is a risk factor for EBV-associated lymphomas. Here, we demonstrate that endogenous LMP1 escapes degradation upon accumulation within intraluminal vesicles of multivesicular endosomes and secretion via exosomes. LMP1 associates and traffics with the intracellular tetraspanin CD63 into vesicles that lack MHC II and sustain low cholesterol levels, even in 'cholesterol-trapping' conditions. The lipid-raft anchoring sequence FWLY, nor ubiquitylation of the N-terminus, controls LMP1 sorting into exosomes. Rather, C-terminal modifications that retain LMP1 in Golgi compartments preclude assembly within CD63-enriched domains and/or exosomal discharge leading to NF-κB overstimulation. Interference through shRNAs further proved the antagonizing role of CD63 in LMP1-mediated signalling. Thus, LMP1 exploits CD63-enriched microdomains to restrain downstream NF-κB activation by promoting trafficking in the endosomal-exosomal pathway. CD63 is thus a critical mediator of LMP1 function in- and outside-infected (tumour) cells. 相似文献
118.
Guichard C Ivanyi-Nagy R Sharma KK Gabus C Marc D Mély Y Darlix JL 《Nucleic acids research》2011,39(19):8544-8558
Prion diseases are unique neurodegenerative illnesses associated with the conversion of the cellular prion protein (PrP(C)) into the aggregated misfolded scrapie isoform, named PrP(Sc). Recent studies on the physiological role of PrP(C) revealed that this protein has probably multiple functions, notably in cell-cell adhesion and signal transduction, and in assisting nucleic acid folding. In fact, in vitro findings indicated that the human PrP (huPrP) possesses nucleic acid binding and annealing activities, similarly to nucleic acid chaperone proteins that play essential roles in cellular DNA and RNA metabolism. Here, we show that a peptide, representing the N-terminal domain of huPrP, facilitates nucleic acid annealing by two parallel pathways nucleated through the stem termini. We also show that PrP of human or ovine origin facilitates DNA strand exchange, ribozyme-directed cleavage of an RNA template and RNA trans-splicing in a manner similar to the nucleocapsid protein of HIV-1. In an attempt to characterize inhibitors of PrP-chaperoning in vitro we discovered that the thioaptamer 5'-GACACAAGCCGA-3' was extensively inhibiting the PrP chaperoning activities. At the same time a recently characterized methylated oligoribonucleotide inhibiting the chaperoning activity of the HIV-1 nucleocapsid protein was poorly impairing the PrP chaperoning activities. 相似文献
119.
The present work delineates the combinatorial approach of firstly, creation of a centralized data-set comprising signalling proteins identified on the basis of altered expression, such as over-expression or repression of a set of signalling protein(s) leading to the cause of the disease, which is based on published reports screened through Pubmed and secondly, in the in silico creation of novel lead (drug) molecules and docking of identified signalling biomarkers using such drugs to investigate possibility of their future application in the model systems eventually. EPAC (Exchange Protein Activated by cAMP) emerges as a signalling biomarker in cases studied presently. Brefeldin, the known inhibitor of EPAC, though the mechanism yet unexplored, has been the molecule used as the pharmacophore for creation of lead drug molecule. Various modifications have been incorporated into the pharmacophore to increase the hydrophobic interactions for increasing the binding efficiency of the generated lead molecule. Side-chain modifications of the pharmacophore and refinement of data through firedock upon docking of EPAC with the modified pharmacophore yielded best results on the bases of atomic contact energy, van der Waal and partial electrostatic interactions as well as additional estimations of the binding free energy. Modifications of CH3 at C15 with COOH and H at C2 with OH in brefeldin showed the best docking results on the basis of protein-drug interaction parameters. The present work provides a clue in rational design of EPAC inhibitors which could be developed as drug lead in combating CVD. 相似文献
120.
Type 1 diabetes mellitus (DM 1A) is an autoimmune disease belonging to the most frequent chronic diseases of the childhood and young adults. DM 1A results from immune-mediated destruction of the insulin-producing beta cells of the pancreas. It is a genetically determined disease and many genes or genetic regions were found to be associated with its induction. In addition to the insulin-dependent diabetes mellitus 1 (IDDM1) gene, which marks the HLA region, and IDDM2 which marks the insulin gene, significant associations of DM 1A to other IDMM genes or genetic regions we reported. We shortly review recent achievements in the field, and the state of current knowledge. 相似文献