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排序方式: 共有204条查询结果,搜索用时 46 毫秒
1.
Daria Corcos Luca Mazzon Pierfilippo Cerretti Maurizio Mei Edoardo Giussani Andrea Drago 《国际虫害防治杂志》2020,66(3):215-221
AbstractThe tiger mosquito is a key vector of several human diseases and is considered a public health concern worldwide. The implementation of strategies aimed at maximizing mosquito control without affecting non-target insect groups is of major importance. In a field trial, we tested the efficiency of a natural pyrethrum-based vs. a synthetic pyrethroid-based insecticide in reducing tiger mosquito population and how they affect the diversity of non-target flower-visiting insects in green urban areas. Only the pyrethroid insecticide was effective in reducing mosquito abundance, although its effects disappeared nine days after application. The two adulticides did not significantly affect the diversity of flower-visiting insects, probably because of their large body size and the difference in flying and foraging activity. To effectively control mosquito populations while preventing intoxication of non-target flower-visiting insects, adulticide applications should be applied early in the morning and only on bushes and trees. Results from our small-scale applications cannot be extrapolate when larger areas are treated. 相似文献
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Maurizio Annoni Simone Borgonovo Marina Aralla 《Veterinary and comparative oncology》2023,21(3):469-481
Several sentinel lymph node (SLN) mapping techniques, to detect nodal metastasis in canine tumours have been investigated in the last 10 years in veterinary oncology. The purpose of this prospective study was to describe a reliable, quick, and inexpensive technique for SLN mapping in canine patients affected by cutaneous and subcutaneous mast cell tumours (MCT). Eighty dogs were enrolled in this study for a total of 138 cytologically diagnosed MCTs. Sentinel lymph node mapping was performed by injecting iomeprole peritumorally followed by serial radiographs at 1, 3, 6 and 9-min post injection. A total of 168 SLNs were detected, 90% at first radiograph, 1 min after the peritumoral iomeprole injection, while in the rest of the cases SLN was identified at 3 min. Sentinel lymph nodes detected by the preoperative radiographic indirect lymphography with iomeprole (PRILI) differed from regional lymph nodes in 57% of cases. The PRILI technique detected simultaneously multiple SLNs in the 26% of cases and multiple lymph centers in the 31% of MCTs. To allow the surgical identification of the SLNs, a peritumoral injection of methylene blue was performed at the time of surgery. This study reports a widely available technique for SLN mapping using digital radiographs in combination with a water-soluble medium, representing a cost-effective alternative to other SLN mapping procedures. Based on our results, this technique can be effective for SLNs mapping in dogs with MCTs but further comparative studies are needed to assess its reliability and efficacy in different tumours. 相似文献
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A survey program was carried out from June 1988 to august 1989 in North-eastern Italy in a pipe drainage area of 61 ha in order to verify if the year of installation (one part of the system has been installed in 1984 and another one year later) and the cover material of drains (pipes were covered with cocofibre for 2/5 of their length and without envelope for 3/5) could influence the functioning of the system. Collected data of drain discharge and water table depth were subjected to an elaborate statistical analysis.A methodological approach to determine the sample size (how many measurements of discharge and watertable depth are required, in space and time, from a statistical stand-point) in drainage experiment is proposed. For drainage systems similar to the considered one, a sample size of 10–12 drains and 6–8 observation wells can be recommended in order to obtain a standard error lower than 10–15% of the mean. 相似文献
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The effects of malolactic fermentation (MLF) on the concentration of volatile compounds released by yeasts during the production of red wine were investigated by inoculation with four commercial starters of Oenococcus oeni. Volatile compounds in wine at the end of MLF were extracted, analyzed by GC-MS and GC, and compared with those extracted form a noninoculated reference sample. Several esters known to play a role in the aroma profile of red wine, such as C4-C8 ethyl fatty acid esters and 3-methylbutyl acetate, were found to increase with MLF, and their final concentration was dependent on the bacterial starter employed for the induction of MLF. The overall increase of ethyl fatty acid esters was generally larger than the one observed for acetate esters. Ethyl lactate, 3-hydroxybutanoate, 2-phenylethanol, methionol, and gamma-butyrolactone were also increased by bacterial metabolism. The impact of MLF on other volatiles or red wine, including several higher alcohols, fatty acids, and nitrogen compounds, was generally negligible. 相似文献
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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
9.
Cairoli P Pieraccini S Sironi M Morelli CF Speranza G Manitto P 《Journal of agricultural and food chemistry》2008,56(3):1043-1050
A number of N2-alkyl and N2-acyl derivatives of guanosine 5'-phosphate (GMP) have been synthesized and tested for their synergistic effect with monosodium L-glutamate (MSG), the prototypical substance imparting umami taste to savory-based foods. Capacities to enhance the taste intensity of MSG (gamma values) were estimated through subjective comparisons of MSG/nucleotide mixtures in water with appropriate solutions of MSG alone. Assuming beta = gamma[nucleotide]/gamma[IMP], beta values of the N2-substituted GMPs were found in the range 1.2-5.7. Such values appear to be related to the chain length of the substituent in the 2-position of the purine nucleus and dependent on the replacement of a CH 2 group with an S atom and/or with an alpha-CO group. These findings indicate that the exocyclic NHR group of the guanine moiety is actively implicated in the synergism between GMP derivatives and MSG. Theoretical calculations suggest that an anti conformation is probably assumed by ribonucleotide molecules interacting with umami receptors. 相似文献
10.
Das Sourav Baumgartner John B. Esperon-Rodriguez Manuel Wilson Peter D. Yap Jia-Yee S. Rossetto Maurizio Beaumont Linda J. 《Landscape Ecology》2019,34(12):2883-2896
Landscape Ecology - Climate refugia—areas that remain suitable for species during periods of climate disruption—have played an important role in species persistence over time.... 相似文献