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91.
Lilian Sonego Susan Lurie Yohanan Zuthi Tatiana Kaplonov Ruth Ben-Arie Itzhak Kosto 《Journal of agricultural and food chemistry》2002,50(3):544-548
Table grapes of cv. Mystery and Prime were harvested from 10 farms in two growing areas of Israel over two seasons. The grapes were separated on the basis of sucrose solutions from 12 to 18%; soluble solids content (SSC), titratable acidity (TA), and pH were determined; and taste tests were conducted. SSC gave the best correlation with taste tests, and multiple regression of SSC, TA, and pH improved the correlation. There were both seasonal and regional differences in the measured maturity parameters. Lower TA and higher pH were found in grapes from the Jordan Valley. Volatiles were predominantly C(6) compounds hexanal and 2-hexanal, contributing a fresh aroma to the grapes. It is concluded that Mystery and Prime grapes have good organoleptic quality if harvested at SSC levels of >14%. 相似文献
92.
Beier RC Creemer LC Ziprin RL Nisbet DJ 《Journal of agricultural and food chemistry》2005,53(25):9679-9688
Monoclonal antibodies (Mabs) were developed that specifically bind tilmicosin. Keyhole limpet hemocyanin (KLH) and bovine serum albumin (BSA) conjugates were used for the immunogen and plate coating antigen, respectively. The conjugates were synthesized by different methods, resulting in different linkages. Six hybridoma cell lines were isolated that produced Mabs that competed with tilmicosin, and have IgG1 isotype. The Til-1 and Til-5 Mabs had IC50 values for tilmicosin of 9.6 and 6.4 ng/well (48 and 32 ng/mL), respectively, and limits of detection at IC20 of 1.84 and 0.89 ng/well (9.2 and 4.45 ng/mL), respectively. The Mabs demonstrated high cross-reactivity to the macrolides containing 3,5-dimethylpiperidine at C20 and the amino sugar at C5. No cross-reactivity was observed for tylosin and other macrolides that did not contain 3,5-dimethylpiperidine. A competitive enzyme-linked immunosorbent assay (ELISA) was developed for the antibiotic tilmicosin by use of the developed Mabs. These Mabs may be excellent candidates for the determination and immunolocalization of tilmicosin. 相似文献
93.
Ewaldo Mattos-Junior Bruno H. Pypendop Tatiana M. Cabrini Cristiane S. Honsho Lilian T. Nishimura 《Veterinary anaesthesia and analgesia》2021,48(4):541-544
ObjectiveTo evaluate the effects of dexmedetomidine alone or in combination with different opioids on intraocular pressure (IOP) in dogs.Study designExperimental, prospective, crossover, randomized, blinded study.AnimalsA total of six Beagle dogs (two males and four females) aged 2 years and weighing 15.9 ± 2.9 kg (mean ± standard deviation).MethodsDogs were distributed randomly into seven treatments (n = 6 per treatment) and were administered dexmedetomidine alone (10 μg kg–1; Dex) or in combination with butorphanol (0.15 mg kg–1; DexBut), meperidine (5 mg kg–1; DexMep), methadone (0.5 mg kg–1; DexMet), morphine (0.5 mg kg–1; DexMor), nalbuphine (0.5 mg kg–1; DexNal) or tramadol (5 mg kg–1; DexTra). All drugs were administered intramuscularly. IOP was measured before drug injection (time 0, baseline) and every 15 minutes thereafter for 120 minutes (T15–T120).ResultsThere were significant reductions in IOP compared with baseline in treatments Dex and DexMep at times T30–T120, and in treatment DexMet at T15–T90. IOP decreased compared with baseline in treatments DexBut, DexNal and DexTra at all evaluation times. No changes in IOP were seen in treatment DexMor. The mean IOP values in treatment DexMet at T105–T120 were higher than those for other treatments.Conclusions and clinical relevanceDexmedetomidine alone or in combination with butorphanol, meperidine, methadone, nalbuphine or tramadol resulted in decreased IOP for 120 minutes in dogs. The magnitude of the reduction was small and lacked clinical significance. 相似文献
94.
甘蔗近缘野生种蔗茅(Erianthus rufipilus)的研究 总被引:4,自引:0,他引:4
本研究表明蔗茅(Erianthusrufipilus)在我国分布于滇、黔、川、藏、桂、陕、甘、鄂8省(区)海拔480-2800米的区域。其体细胞染色体数目为2N=20,不同区域的无性系2N数目未发现变异,但减数分裂染色体配对构型略有差异.蔗茅茎秆的锤度普遍较高,最高可达22%,但种群内变异较大,即使同一野生群落内也有明显差异。蔗茅同一个体不同小穗内的花药数目变异较大,总体变化在0—3枚之间。蔗茅的高锤度、花药数目的易变性及染色体数目的稳定性表明:蔗茅在甘蔗起源和进化上具有一定的重要性,在甘蔗育种的基础研究上应给予重视。,达极显著水平。表2列出了14个蔗茅无性系的花药数目的小穗百分率。总体而言,可按百分率把蔗茅的花药数目变异为4类:(1)以3花药小穗为主,同时出现2花药和单花药的小穗,西藏、四川和陕西都有这类无性系出现,共有6个无性系。(2)以单花药小穗为主,同时出现3花药、2花药和无花药小穗,共有5个无性系,原产于云南和西藏。(3)以2花药小穗为主,同时出现3花药和单花药小穗;共2有个无性系,原产于四川和云南。(4)3花药、2花药、单花药小穗百分率基本相等,只见于陕西的一个无性系中。从地理上看,云南和西藏的? 相似文献
95.
Sensitivity of landscape resistance estimates based on point selection functions to scale and behavioral state: pumas as a case study 总被引:1,自引:1,他引:0
Katherine A. Zeller Kevin McGarigal Paul Beier Samuel A. Cushman T. Winston Vickers Walter M. Boyce 《Landscape Ecology》2014,29(3):541-557
Estimating landscape resistance to animal movement is the foundation for connectivity modeling, and resource selection functions based on point data are commonly used to empirically estimate resistance. In this study, we used GPS data points acquired at 5-min intervals from radiocollared pumas in southern California to model context-dependent point selection functions. We used mixed-effects conditional logistic regression models that incorporate a paired used/available design to examine the sensitivity of point selection functions to the scale of available habitat and to the behavioral state of individual animals. We compared parameter estimates, model performance, and resistance estimates across 37 scales of available habitat, from 250 to 10,000 m, and two behavioral states, resource use and movement. Point selection functions and resistance estimates were sensitive to the chosen scale of the analysis. Multiple characteristic scales were found across our predictor variables, indicating that pumas in the study area are responding at different scales to different landscape features and that multi-scale models may be more appropriate. Additionally, point selection functions and resistance estimates were sensitive to behavioral state; specifically, pumas engaged in resource use behavior had an opposite selection response to some land cover types than pumas engaged in movement behavior. We recommend examining a continuum of scales and behavioral states when using point selection functions to estimate resistance. 相似文献
96.
97.
Li Y Wang Z Beier RC Shen J De Smet D De Saeger S Zhang S 《Journal of agricultural and food chemistry》2011,59(8):3441-3453
This review focuses on the toxicity and metabolism of T-2 toxin and analytical methods used for the determination of T-2 toxin. Among the naturally occurring trichothecenes in food and feed, T-2 toxin is a cytotoxic fungal secondary metabolite produced by various species of Fusarium. Following ingestion, T-2 toxin causes acute and chronic toxicity and induces apoptosis in the immune system and fetal tissues. T-2 toxin is usually metabolized and eliminated after ingestion, yielding more than 20 metabolites. Consequently, there is a possibility of human consumption of animal products contaminated with T-2 toxin and its metabolites. Several methods for the determination of T-2 toxin based on traditional chromatographic, immunoassay, or mass spectroscopy techniques are described. This review will contribute to a better understanding of T-2 toxin exposure in animals and humans and T-2 toxin metabolism, toxicity, and analytical methods, which may be useful in risk assessment and control of T-2 toxin exposure. 相似文献
98.
Li X Luo P Tang S Beier RC Wu X Yang L Li Y Xiao X 《Journal of agricultural and food chemistry》2011,59(11):6064-6070
A simple, rapid and sensitive immunogold chromatographic strip test based on a monoclonal antibody was developed for the detection of melamine (MEL) residues in raw milk, milk products and animal feed. The limit of detection was estimated to be 0.05 μg/mL in raw milk, since the detection test line on the strip test completely disappeared at this concentration. The limit of detection was 2 μg/mL (or 2 μg/g) for milk drinks, yogurt, condensed milk, cheese, and animal feed and 1 μg/g for milk powder. Sample pretreatment was simple and rapid, and the results can be obtained within 3-10 min. A parallel analysis of MEL in 52 blind raw milk samples conducted by gas chromatography-mass spectrometry showed comparable results to those obtained from the strip test. The results demonstrate that the developed method is suitable for the onsite determination of MEL residues in a large number of samples. 相似文献
99.
Sophie Cornu Saskia Keesstra Antonio Bispo Maria Fantappie Fenny van Egmond Bozena Smreczak Rafał Wawer Lenka Pavlů Jaroslava Sobocká Zsófia Bakacsi Kinga Farkas-Iványi Sándor Molnár Anders Bjørn Møller Sevinc Madenoglu Dalia Feiziene Katrien Oorts Florian Schneider Maria da Conceição Gonçalves Raquel Mano Gina Garland Rastislav Skalský Lilian O'Sullivan Raimonds Kasparinskis Claire Chenu 《European Journal of Soil Science》2023,74(4):e13398
At the European scale, soil characteristics are needed to evaluate soil quality, soil health and soil-based ecosystem services in the context of the European Green Deal. While some soil databases exist at the European scale, a much larger wealth of data is present in individual European countries, allowing a more detailed soil assessment. There is thus an urgent and crucial need to combine these data at the European scale. In the frame of a large European Joint Programme on agricultural soils launched by the European Commission, a survey was conducted in the spring of 2020, in the 24 European participating countries to assess the existing soil data sources, focusing on agricultural soils. The survey will become a contribution to the European Soil Observatory, launched in December 2020, which aims to collect metadata of soil databases related to all kind of land uses, including forest and urban soils. Based upon a comprehensive questionnaire, 170 soil databases were identified at local, regional and national scales. Soil parameters were divided into five groups: (1) main soil parameters according to the Global Soil Map specifications; (2) other soil chemical parameters; (3) other physical parameters; (4) other pedological parameters; and (5) soil biological features. A classification based on the environmental zones of Europe was used to distinguish the climatic zones. This survey shows that while most of the main pedological and chemical parameters are included in more than 70% of the country soil databases, water content, contamination with organic pollutants, and biological parameters are the least frequently reported parameters. Such differences will have consequences when developing an EU policy on soil health as proposed under the EU soil strategy for 2023 and using the data to derive soil health indicators. Many differences in the methods used in collecting, preparing, and analysing the soils were found, thus requiring harmonization procedures and more cooperation among countries and with the EU to use the data at the European scale. In addition, choosing harmonized and useful interpretation and threshold values for EU soil indicators may be challenging due to the different methods used and the wide variety of soil land-use and climate combinations influencing possible thresholds. The temporal scale of the soil databases reported is also extremely wide, starting from the '20s of the 20th century. 相似文献
100.
Liang Guo Liangliang Hu Lufeng Zhao Xiaoyu Shi Zijun Ji Lilian Ding Weizheng Ren Jian Zhang Jianjun Tang Xin Chen 《水稻科学》2020,27(3):175-179
正About 30 million hectares of rice are cultivated annually in China (FAOSTAT,2019).Because most rice fields are wellirrigated and suitable for fish living ('fish'here refers to various aquatic animals like carps,prawns,crabs,soft shell turtles,etc.)(Fernando,1993),many efforts have been made to determine how well rice farming and aquaculture can be coupled as a rice-fish system (RFS),of which the same land and water produces both rice and aquatic products.With the technological 相似文献