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排序方式: 共有334条查询结果,搜索用时 15 毫秒
1.
Cinzia Calcabrini Roberta De Bellis Umberto Mancini Luigi Cucchiarini Vilberto Stocchi Lucia Potenza 《Plant foods for human nutrition (Dordrecht, Netherlands)》2017,72(2):192-197
Walnuts (Juglans regia L.) are relevant components of the Mediterranean diet providing important macronutrients, micronutrients and other bioactive constituents including unsaturated fatty acids, proteins, fiber, vitamins, minerals, phytosterols and polyphenols. Although the walnut beneficial effects in human health are widely recognized by a lot of epidemiologic studies very little is known regarding its effect on damaged DNA. The aim of the present study was to investigate the effect of Juglans regia L. ethanolic extract from kernel on the induction of DNA strand breaks by thiol/Fe3+/O2 mixed function oxidase, tert-butyl hydroperoxide or UVC radiations in acellular and cellular models. Plasmid DNA cleavage and fast Halo assay were used to monitor oxidative damage to DNA. Both approaches showed protection of oxidatively injured DNA. These results agree with a lot of scientific proofs which recommend walnut as dietary adjunct in health promotion and prevention as well as in treatment of lifestyle-related oxidative diseases. 相似文献
2.
Fabrizio Lisi Ramzi Mansour Carmelo Cavallaro Tuğcan Alınç Emanuele Porcu Michele Ricupero Lucia Zappalà Nicolas Desneux Antonio Biondi 《Pest management science》2023,79(12):5003-5014
Background
Although the pupal parasitoid Trichopria drosophilae is used in conservative and augmentative biocontrol of Drosophila suzukii infestations, current pest management strategies mostly rely on multiple insecticide applications. In this context, the aim of the study was to investigate the baseline toxicity of nine insecticides on D. suzukii larvae and their multiple sublethal effects (LC10) on immature stages of the pest feeding on contaminated diet and T. drosophilae developing within the intoxicated host.Results
Chlorpyriphos and azadirachtin showed the lowest and the highest LC10, the values of which were 9.78 × 1013 and 1.46 × 103 times lower than their recommended label field rate, respectively. Among tested insecticides, imidacloprid, malathion and dimethoate were the only treatments that did not affect the juvenile development time of D. suzukii, while spinosad and the organophosphates chlorpyriphos and dimethoate did not influence fly pupal size. No sublethal effects were recorded on T. drosophilae degree of infestation (DI) and juvenile development time. On the contrary, cyazypyr and dimethoate negatively affected the success of parasitism (SP) and the number of progeny of the pupal parasitoid, in association with malathion for the first parameter and spinosad for the fertility. Compared to the untreated control, more female progeny emerged following azadirachtin exposure, while dimethoate caused the opposite effect. Imidacloprid, lambda-cyhalothrin and spinetoram decreased hind tibia length of emerged parasitoids.Conclusion
This study provides new insights on the (eco)toxicological profile of nine insecticides and new information needed to support the deployment of T. drosophilae in the field within the sustainable management techniques against D. suzukii. © 2023 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry. 相似文献3.
The oil of the leaves of Bursera aloexylon was found to contain a high linalool level (96.7 %). The antimicrobial activity tests indicated that the oil was effective against Rhodococcus equi (0.60 mg/ml) and Staphylococcus epidermides (0.15 mg/ml). 相似文献
4.
5.
Immigrants Doing Business in a Mid‐sized Canadian City: Challenges,Opportunities, and Local Strategies in Kelowna,British Columbia 下载免费PDF全文
Lacking a tradition of settling immigrants and the appropriate infrastructure to integrate them, small‐ and medium‐sized cities often face the challenge of attracting and retaining immigrants. Using a mixed methods approach, this study compares the experiences of immigrant and non‐immigrant entrepreneurs in a mid‐sized Canadian city, Kelowna, British Columbia. A survey reveals different experiences between these two groups, with immigrants facing more challenges. In the absence of institutionally complete communities or strong ethnic economies, immigrants do not rely extensively on their own community resources, an element considered instrumental for immigrant business development in large cities. Compared to non‐immigrants, immigrant entrepreneurs have a more optimistic outlook on doing business in Kelowna; this is encouraging for a city trying hard to attract immigrant investment. Key informants recommended transforming the city into a more welcoming community, establishing appropriate support infrastructure, and removing potential institutional offsets. This paper adds new theoretical insights to the literature on immigrant entrepreneurship; all socio‐cultural, political‐institutional, and economic‐structural considerations are embedded in geography. The findings also have implications for growth strategies in small‐ and medium‐sized cities. 相似文献
6.
Lucia Lioi 《Euphytica》1989,44(1-2):151-155
Summary Variation of phaseolin, the major storage protein in Phaseolus vulgaris L., was analysed in seeds of a germplasm collection from the Mediterranean area. Results showed a number of subvariants differing from the reference patterns for the presence, absence or faintness of single polypeptides. Maximum concentration of variation was found in the Cyprus material. Sources and causes of variation are discussed. 相似文献
7.
Luciana Rossini Pinto Maria Lucia Carneiro Vieira Cláudio Lopes de Souza Jr Anete Pereira de Souza 《Euphytica》2003,134(3):277-286
BR-105 and BR-106 are important tropical maize populations, which were submitted to a high-intensity reciprocal recurrent
selection, generating the IG-3 and IG-4synthetics. Using 30-microsatellite loci,we measured and compared the genetic diversity
of these populations and their synthetics. The populations did not differ significantly regarding the amount of genetic diversity.
As a consequence of selection, genetic variability losses, in terms of mean number of alleles per locus,proportion of polymorphic
loci, and gene diversity did occur and were greater in the synthetic IG-3 than IG-4. In the synthetics, the number of loci
in adherence to Hardy-Weinberg proportions was superior to that observed in the populations. The Wright's mean fixation index
was higher than the mean value expected for outcrossing species (5%) indicating as light excess of homozygotic individuals
in both populations. The genetic distances confirmed the favourable effects of one cycle of recurrent selection, as the synthetics
became more isolated in comparison to the original populations.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
8.
Cabrera A Cox L Velarde P Koskinen WC Cornejo J 《Journal of agricultural and food chemistry》2007,55(12):4828-4834
The addition of organic amendments to soil increases soil organic matter content and stimulates soil microbial activity. Thus, processes affecting herbicide fate in the soil should be affected. The objective of this work was to investigate the effect of olive oil production industry organic waste (alperujo) on soil sorption-desorption, degradation, and leaching of diuron [3-(3,4-dichlorophenyl)-1,1-dimethylurea] and terbuthylazine [N2-tert-butyl-6-chloro-N4-ethyl-1,3,5-triazine-2,4-diamine], two herbicides widely used in olive crops. The soils used in this study were a sandy soil and a silty clay soil from two different olive groves. The sandy soil was amended in the laboratory with fresh (uncomposted) alperujo at the rate of 10% w/w, and the silty clay soil was amended in the field with fresh alperujo at the rate of 256 kg per tree during 4 years and in the laboratory with fresh or composted alperujo. Sorption of both herbicides increased in laboratory-amended soils as compared to unamended or field-amended soils, and this process was less reversible in laboratory-amended soils, except for diuron in amended sandy soil. Addition of alperujo to soils increased half-lives of the herbicides in most of the soils. Diuron and terbuthylazine leached through unamended sandy soil, but no herbicide was detected in laboratory-amended soil. Diuron did not leach through amended or unamended silty clay soil, whereas small amounts of terbuthylazine were detected in leachates from unamended soil. Despite their higher sorption capacity, greater amounts of terbuthylazine were found in the leachates from amended silty clay soils. The amounts of dissolved organic matter from alperujo and the degree of humification can affect sorption, degradation, and leaching of these two classes of herbicides in soils. It appears that adding alperujo to soil would not have adverse impacts on the behavior of herbicides in olive production. 相似文献
9.
The antioxidizing potency of phenol compounds contained in olive oil mill wastewater (OOMWW) has been elucidated. Commercially available phenol standards at varying concentrations and the Rancimat oxidation test have been used. Refined purified olive oil was utilized as an oxidation lipid substrate. Synthetic antioxidants, such as 2,3-tert-butyl-4-hydroxyanisole (BHA), 3,5-di-tert-butyl-4-hydroxytoluene (BHT), l-ascorbic acid, and gallates (commonly used as food preservatives), and other known chemicals endowed with antioxidizing properties have been employed as reference compounds. The OOMWW phenol compounds have been classified into different groups depending on their antioxidizing potency. This was significantly affected by the tested concentrations of the standards. Mixtures of phenol standards and other antioxidants (l-proline, chlorophyll a, chlorophyll b, and alpha-, gamma-, and delta-tocopherol) have also been tested. Many phenol compounds present in OOMWW showed antioxidizing potency higher compared to that of the less safe synthetic antioxidants and could therefore replace these in the industrial preservation of food items. They could also be used in combination with other natural antioxidants (e.g., tocopherols). In fact, some mixtures of antioxidants, owing also to the synergistic phenomena, showed strong antioxidizing potency. 相似文献
10.
Antioxidants,free radicals,storage proteins,and proteolytic activities in wheat (Triticum durum) seeds during accelerated aging 总被引:3,自引:0,他引:3
Galleschi L Capocchi A Ghiringhelli S Saviozzi F Calucci L Pinzino C Zandomeneghi M 《Journal of agricultural and food chemistry》2002,50(19):5450-5457
Accelerated aging was performed by incubation of wheat seeds at 40 degrees C and 100% relative humidity for 3, 4, 6, 10, and 14 days. The effects of the treatment on seed germinability and on several biochemical characteristics of flour (carotenoids, free radical and protein contents, and proteolytic activity) and gluten (free radical content and flexibility) were evaluated. A decrease of germinability was found during aging, the germination being completely inhibited after 14 days. The lutein content decreased gradually, without going to zero, while that of free radicals increased. A reduction of soluble proteins and a degradation of glutenins and gliadins were observed, associated with a substantial increase of protease activity and a decrease in gluten flexibility. The results were discussed in reference to those previously obtained by natural aging of wheat seeds of the same species and cultivar. 相似文献