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991.
The effect of the auxins dicamba (3,6-dichloro-2-methoxybenzoic acid) and picloram (4-amino-3,5,6-trichloropicolinic acid) on callus growth and embryogenesis in Phoenix dactylifera L. was investigated. Maximum callus fresh weight was obtained in nutrient medium enriched with 200 µm picloram. Somatic embryogenesis and subsequent plant regeneration was achieved following transfer of such calli to hormone-free medium. Germination of the somatic embryos was influenced by treatment with the chemical mutagen ethylmethanesulphonate (EMS). Uptake of the labelled mutagen ([14C]EMS) by the somatic embryos increased with increased incubation time. Presence of dimethyl sulphoxide (DMSO) as a carrier agent during mutagenic treatment was necessary for efficient mutagen uptake. 相似文献
992.
Bacteriological analyses were made on 45 swab samples secured from hands of poultry workers on processing line, on 31 bruised and 15 normal poultry tissue samples, and on 15 swabs obtained from infected lacerations and exudates of abcesses on hands, arms, chest, and abdomen of poultry workers. A total of 170 Staphylococcus cultures were isolated from samples examined. These cultures were characterized morphologically and biochemically and then grouped into six distinct patterns. S. aureus was found in 86.6% of swab samples obtained from infected workers, in 40% of swabs from hands of workers who handle bruised birds, and in 38.7% of bruised tissues, and was absent from all samples obtained from hands of workers who do not handle bruised birds. All the coagulase-positive staphylococcal isolates were bacteriophage-typed, and the results showed that the same phage-type S. aureus was found in many poultry bruises and in infected lesions of poultry workers as well as on hands of workers who handle bruised birds. These results indicate that poultry bruises are a source of staphylococcal infection encountered among poultry workers. 相似文献
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Edgar E. Becerril-García Edgar M. Hoyos-Padilla Omar Santana-Morales Miguel A. Gutiérrez-Ortiz Arturo Ayala-Bocos Felipe Galván-Magaña 《Journal of fish biology》2020,97(6):1861-1864
The aim of the present study is to provide an estimate of the number of white sharks Carcharodon carcharias that seasonally interact with ecotourism boats in Guadalupe Island using Schnabel's mark–recapture method and 6316 records of white sharks during 2012–2014. The results of the estimation highlight an abundance of 78 white sharks 95% C.I. (62.1, 105.6) interacting with ecotourism. The regulations regarding the number of tourists, boats and the monitoring of white sharks should be assessed to improve management decisions regarding the conservation and sustainable use of this threatened species. 相似文献
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Salaheldin Abdelsalam Abdullah M. Alzahrani Omar M. Elmenshawy Ashraf M. Abdel‐Moneim 《Entomological Research》2020,50(6):309-316
Red palm weevil, Rhynchophorus ferrugineus, destroys palms almost all over the world, especially in the Middle East, where dates are a strategic crop in arid places. In view of the urgent need to combat this destructive pest, effective pesticides with high environmental safety should be sought. Spinosad is a pesticide of bacterial origin that is presumed to have a high degree of environmental safety and is effective in combating a wide range of insect pests. In this study, the efficacy of spinosad was evaluated in females of R. ferrugineus. The lethal concentration for 50% of the treated females was calculated at 44.3 ppm. The effects of spinosad concentrations of 10, 50 and 200 ppm on the activity of catalase (CAT), glutathione S‐transferase (GST) and superoxide dismutase (SOD) in the ovaries were assessed. In addition, the pathological effects of these concentrations were documented on the ultrastructure of the follicle cells and ooplasm. The results showed a significant increase in CAT activity only in response to treatment with 200 ppm. Treating the females with different spinosad concentrations resulted in varying intensity changes in cell organelles, where the most pronounced sign of programmed cell death was at the concentration 200 ppm. This study demonstrates the possibility of using spinosad as an insecticide against females of R. ferrugineus. 相似文献
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Investigating cranial morphological variation of early human skeletal remains from Chile: A 3D geometric morphometric approach 下载免费PDF全文
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