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排序方式: 共有329条查询结果,搜索用时 31 毫秒
321.
Plants display a diverse array of inducible changes in secondary metabolites following insect herbivory. Herbivores differ in their feeding behavior, physiology, and mode of attachment to the leaf surface, and such variations might be reflected in the induced responses of damaged plants. Induced changes were analyzed for Minthostachys mollis, a Lamiaceae with medicinal and aromatic uses, and four species of folivore insects with different feeding habits (chewing, scraping, sap-sucking, and puncturing). In M. mollis leaves experimentally exposed to the insects, levels of the two dominant monoterpenes pulegone and menthone were assessed 24 and 48 h after wounding. Menthone content generally decreased in the essential oil of damaged leaves, whereas pulegone concentration increased in all treatments. These changes occurred also in the adjacent undamaged leaves, suggesting a systemic response. The relatively uniform response to different kinds of damage could be attributable to the presence of such a strongly active compound as pulegone in the essential oil of M. mollis. The effects of wounding on essential oil concentration may be significant from a commercial point of view. 相似文献
322.
Emilio Alemán Frias Otto Aurich Lilia Ezcurra Ferrer Manuel Gutiérrez Vázquez Christian Horstmann Julio López Rendueles Edith Rodriguez Graquitena Eugenio Roquel Casabella Klaus Schreiber 《Genetic Resources and Crop Evolution》1972,19(1):359-425
Zusammenfassung In Zusammenarbeit zwischen der Akademie der Wissenschaften Kubas und der Deutschen Akademie der Wissenschaften zu Berlin wurden 1165 Pflanzenarten aus 149 Familien der kubanischen Flora nach Standardverfahren orientierend auf Alkaloide und Saponine untersucht. Die Ergebnisse sind in Tabelle 2 aufgeführt.
Phytochemical investigations in plants of the Cuban flora
Summary In cooperation of the Academy of Sciences of Cuba with the German Academy of Sciences at Berlin 1165 species from 149 plant families of the Cuban flora have been preliminarily investigated by standard methods with regard to the occurrence of alkaloids and saponins. The results are compiled in table 2.
1165 149 . . . 2.相似文献
323.
Casini C Dardanelli JL Martínez MJ Balzarini M Borgogno CS Nassetta M 《Journal of agricultural and food chemistry》2003,51(21):6309-6313
The ratio of oleic to linoleic acids (O/L) and the tocopherol content are important features in determining peanut (Arachis hypogaea) seed shelf life. Soluble carbohydrates are known to be important precursors in roasted peanut flavor. The chemical qualities of Argentine grain are different from those of other countries, but no previous studies that associate grain quality and environmental parameters have been performed. Relationships were determined between O/L, tocopherol and sugar contents, and variations in temperature and rainfall during the grain filling period of Florman INTA peanuts. Dry seed yield was used as another explanatory variable. Multiple regression procedure gave mean temperature (positive coefficient) and total precipitation (negative coefficient) as the explanatory variables for variations in O/L. Total precipitation and dry seed yield (both negative coefficients) were found to be predictor variables for tocopherol and sugar contents. Total precipitation was an explanatory variable included in all of the linear regression models obtained in this study. 相似文献
324.
Maria Isabel Gonzalez Urrego Raquel Silveira Pedreira Karine de Melo Santos Mariane Ceschin Ernandes João Paulo Fernandes Santos Thiago Henrique Annibale Vendramini Marcos Nogueira Eberlin Julio Cesar de Carvalho Balieiro Cristiana Ferreira Fonseca Pontieri Marcio Antonio Brunetto 《Journal of animal physiology and animal nutrition》2021,105(Z1):65-75
The strong odour of faeces and excessive production of gases in some dog breeds have long been a concern of owners. The pet food industry uses nutritional alternatives, such as high-quality ingredients and additives, to improve the odour of faeces. However, there are still some dog breeds, such as the French Bulldog, that present this problem due to the presence into the large intestine of indigested protein. Therefore, a deeper understanding of the volatile compounds that influence the odour of dog faeces is important. This study aimed to identify changes of faecal odour compounds that are most prevalent in French Bulldogs based on food containing different high-quality protein sources and their effect in sensory analysis. Four maintenance foods with different protein sources were formulated: P, poultry meal food; W, wheat gluten food; PW, poultry meal and wheat gluten food; and PWH, poultry meal, wheat gluten, and hydrolysed protein food. Eight adult French Bulldogs were arranged in a 4x4 Latin square design and adapted to foods for 28 days. Fresh faeces were collected for analysis of volatile organic compounds (VOCs) and sensory analysis. The means were compared by SAS, and statistical significance was indicated by p ≤ 0.05. No adverse effects were observed in the animals regarding VOCs, and a significant difference was observed in two of the 68 compounds identified. The animals fed a P food had higher concentrations of phenol in the faeces, whereas the indole compound was present at higher concentrations in animals fed the W food. P food was associated with higher odour perception during sensory evaluation. In summary, the source of protein in the foods had little impact on the composition of VOCs, and a greater perception of the odour was determined by sensory analysis when foods containing animal protein were administered. 相似文献
325.
326.
Components of resistance were investigated for five adult-plant resistant (APR) wheat (Triticum aestivum) cultivars at six growth stages and two temperatures in the greenhouse, and disease progress in a field trial. Chinese cultivar Chuanyu 12displayed high to intermediate infection type (IT) in the greenhouse but was highly resistant in the field. Weebill showed an intermediate IT in the greenhouse and also in the field. Chpaio, Tukuru and Saar, known to carry combinations of Yr18and 2-3 additional minor genes, were highly resistant in both experiments. Greenhouse experiments indicated that the lower IT of APR cultivars initiated at tillering stage. Latent periods (LP) for APR cultivars were generally longer as the growth stage progressed. We conclude that APR to stripe rust can be best characterized in field trials although significant correlations are seen between field severity and IT and LP measured in the greenhouse. 相似文献
327.
328.
Asara et al. (Reports, 13 April 2007, p. 280) reported sequencing of Tyrannosaurus rex proteins and used them to establish the evolutionary relationships between birds and dinosaurs. We argue that the reported T. rex peptides may represent statistical artifacts and call for complete data release to enable experimental and computational verification of their findings. 相似文献
329.
Garcia-Montijano M Waxman S Lucas JJ Luaces I Zalba J González F Andrés MI Rodríguez C 《Veterinary journal (London, England : 1997)》2006,171(3):551-555
This study reports on the administration of a single dose of marbofloxacin (2 mg/kg) to five adult Eurasian buzzards (Buteo buteo) by the intraosseous (IO) route, which has been proposed as a rapid and efficient means for the parenteral delivery of antimicrobial drugs. The drug was rapidly absorbed. Peak marbofloxacin concentration (C(max)) in plasma and area under the concentration-time curve (AUC) of 1.92+/-0.78 microg/mL and 8.53+/-2.73 microg h/mL, respectively. The time marbofloxacin remained in the plasma after IO administration was relatively short (elimination half-life, t(1/2beta)=4.91+/-0.65 h; mean residence time (MRT)=5.38+/-0.57 h). Single dose marbofloxacin gave values for C(max)/minimum inhibitory concentration (MIC) of 19.2 and an AUC/MIC value of 85.3h after IO administration. The IO route appears to be practical and effective for the rapid delivery of marbofloxacin to buzzards. 相似文献