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排序方式: 共有1406条查询结果,搜索用时 140 毫秒
121.
ABSTRACT Late leaf spot (LLS), caused by Phaeoisariopsis personata, is a foliar disease of groundnut or peanut (Arachis hypogaea) with high economic and global importance. Antifungal and chitinolytic Bacillus circulans GRS 243 and Serratia marcescens GPS 5, selected among a collection of 393 peanut-associated bacteria, were applied as a prophylactic foliar spray and tested for control of LLS. Chitin-supplemented application of B. circulans GRS 243 and S. marcescens GPS 5 resulted in improved biological control of LLS disease. Supplementation of bacterial cells with 1% (wt/vol) colloidal chitin reduced lesion frequency by 60% compared with application of bacterial cells alone, in the greenhouse. Chitinsupplemented application of GRS 243 and GPS 5 also resulted in improved and stable control of LLS in a repeated field experiment and increased the pod yields by 62 and 75%, respectively, compared with the control. Chitin-supplemented application of GPS 5 was tested in six onfarm trials, and the increase in pod yields was up to 48% in kharif (rainy season). A 55-kDa chitinase was purified from the cell-free culture filtrate of GPS 5 by affinity chromatography and gel filtration. Purified chitinase of S. marcescens GPS 5 (specific activity 120 units) inhibited the in vitro germination of P. personata conidia, lysed the conidia, and effectively controlled LLS in greenhouse tests, indicating the importance of chitinolysis in biological control of LLS disease by GPS 5. 相似文献
122.
Arencibia A Rivero MA Gil F Ramírez JA Corbera JA Ramírez G Vázquez JM 《Anatomia, histologia, embryologia》2005,34(1):52-55
The objective of this study was to define the anatomy of the cranioencephalic structures and associated formations in camel using magnetic resonance imaging (MRI). MR images were acquired in sagittal, transverse and oblique dorsal planes, using spin-echo techniques, a magnet of 1.5 T and a standard human body coil. MR images were compared with corresponding frozen cross-sections of the head. Different anatomic structures were identified and labelled at each level. The resulting images provided excellent soft tissue contrast and anatomic detail of the brain and associated structures of the camel head. Annotated MR images from this study are intended to be a reference for clinical imaging studies of the head of the dromedary camel. 相似文献
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124.
Semi-finished meat products were demonstrated to be heavily contaminated with microbes already at the moment of production. The main source of microorganisms was meat surface. Psychrotolerant organisms represented the main factors involved in the rise of organoleptical signs of decay. For the evaluation of the level of hygiene and sanitation, quality of the raw materials used and conditions of storage, the maximal limit values were proposed for 10 species or groups of the microorganisms under study. Pathogenic microorganisms were not detected by the multiplication method in any of the samples. 相似文献
125.
Water transmission characteristics under saturated and unsaturated conditions were studied in a sandy loam soil with (F1) and without (F0) long-term farmyard manure (FYM) treatments, in relation to sodium adsorption ratios (SAR) and electrolyte concentrations of water. The effect of FYM and ratios of Ca2+ : Mg2+ in water at a given SAR on sodication of the soil was also studied.Saturated hydraulic conductivity (k) and weighted mean diffusivity () were slightly higher for F1 than for F0, whereas sodication indices like Gapon constant (KG), Krishnamoorthy-Davis-Overstreet constant (KKDO) and Vanselow constant (KV) were slightly smaller. The k and decreased with an increase of SAR and decrease of electrolyte concentration, the effect of SAR being more pronounced. There was proportionately a sharper decrease in the k and values at SAR 10 with total electrolyte concentrations of 10–40 meq 1?1. However, with a total electrolyte concentration of 80 meq 1?1, there was a smaller drop at SAR 10.A small difference in the build-up of exchangeable sodium percentage (ESP) in F1 and F0 treatments at a given SAR suggests that, apart from slightly improving water transmission parameters, the use of FYM also reduces the sodication hazard in a soil irrigated with sodic waters. An increase in the Ca2+ : Mg2+ ratio from 25:75 to 75:25 slightly decreased the values of KG, KKDO and KV, thus indicating somewhat more preference for Ca2+ to Mg2+ at a given SAR, which was more so in F1 soil. This fact could also be expressed in terms of a slight shift of thermodynamic exchange constant (K) and standard free energy change of the exchange reaction (ΔG0r). The presence of some unidentified Na+ releasing minerals in the soils studied was observed and correction for exchangeable Na+ determination applied. 相似文献
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Bonhoeffer et al. (Reports, 26 November 2004, p. 1547) presented evidence for positive epistasis in a clinical data set of HIV-1 mutants and corresponding fitness values. We demonstrate that biases in the original and simulated data sets may lead to erroneous evidence for epistasis. More rigorous statistical tests must be used to account for such biases before one can infer epistasis. 相似文献
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129.
Latorre R Arencibia A Gil F Rivero M Henry RW Ramírez G Váquez JM 《American journal of veterinary research》2006,67(5):756-761
OBJECTIVE: To correlate anatomic features of the equine tarsus identified in plastinated sections with images obtained via magnetic resonance imaging (MRI). ANIMALS: 4 horses. PROCEDURE: MRI (1.5-Tesla magnet) of the tarsus was performed on the pelvic limbs of 4 clinically normal horses following euthanasia. After imaging, tarsocrural joint spaces and vasculature were injected with colored latex. Sagittal and transverse sections of the tarsi were plastinated to facilitate interpretation of MR images. RESULTS: Relevant anatomic structures were identified and labeled on the plastinated tissue slices and corresponding MR images. Results indicated high correlations between MRI findings and those of plastinated sections. CONCLUSIONS AND CLINICAL RELEVANCE: The data obtained provided certain reference standards for normal anatomic structure sizes and positions in the equine tarsus. This information may aid future physiologic or clinical studies of this joint. 相似文献
130.