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791.
Graf TN Levine KE Andrews ME Perlmutter JM Nielsen SJ Davis JM Wani MC Oberlies NH 《Journal of agricultural and food chemistry》2007,55(4):1205-1211
Populations of bloodroot [Sanguinaria canadensis L. (Papaveraceae)] are found throughout the eastern forests of North America, with particular abundance in the southern Appalachian Mountains. Increasingly, it is finding use in Europe as a nonantibiotic animal feed supplement to promote weight gain. As efforts to cultivate this herb are underway, there is a need to understand the effect of agronomic permutations on both the dry mass rhizome yield and the yield of benzophenanthridine alkaloids. Month-to-month variability of the concentration of the alkaloids sanguinarine and chelerythrine in both cultivated and wildcrafted bloodroot was examined. The alkaloid yield was consistently higher, but more variable, in wildcrafted plants. On average, cultivated rhizomes were both larger and more consistently sized than those that were wildcrafted. The concentration of a suite of trace elements was measured in soil that was collected concomitantly with each plant accession. Differences in element profiles were compared against alkaloid yields. 相似文献
792.
Margaret E. Montgomery Lynn M. Woodworth David A. Briscoe 《Biological conservation》2010,143(8):1842-1849
Many threatened species are being maintained in captivity to save them from extinction, often with the eventual aim of reintroduction. The objective of genetic management in captivity is to ‘freeze’ evolution i.e. to avoid genetic adaptation to captivity and to retain genetic diversity. Most current genetic management of threatened species addresses the latter, but does not explicitly address the former. The theory underlying current genetic management and its practical implementation assumes neutrality of loci. However, genetic adaptation in captive populations may cause non-neutral behavior at neutral loci due to selective sweeps (hitchhiking) caused by rapid allele frequency changes at linked fitness loci. We compared changes in microsatellite genetic diversity at eight non-coding loci with neutral predictions in 23 pedigreed captive populations of Drosophila melanogaster maintained with effective sizes of 25 (eight replicates), 50 (6), 100 (4), 250 (3) and 500 (2) for 48 generations. Loss of microsatellite heterozygosity was significantly faster (by 12%) than predicted by neutral theory, as assessed by regressing proportion of heterozygosity retained on pedigree inbreeding coefficients. Further, greater than neutral changes were observed for both variances in allele frequencies across replicates (by 25%), and for temporal changes in allele frequencies (by 33%). All eight microsatellite loci showed signals of selectively-driven changes. Rather than having their evolution ‘frozen’, captive populations are undergoing major genome-wide selective sweeps that affect not only fitness loci but linked neutral loci. Captive genetic management for threatened species destined for reintroduction requires modification to explicitly minimize genetic adaptation to captivity. 相似文献
793.
Robert L. Magaletta Suzanne N. DiCataldo Dong Liu Hong Laura Li Rajendra P. Borwankar Margaret C. Martini 《Cereal Chemistry》2010,87(4):363-369
The glycemic index (GI) is an indicator of the relative human glycemic response to dietary carbohydrates in a food. It is determined using a costly and time‐consuming in vivo method. We describe an in vitro analytical method that allows the accurate prediction of the GI of a food product. The method involves digestion of the food product using HCl and enzymes, followed by HPLC analysis of sugars and sugar alcohols. Data from the HPLC analysis combined with the product's compositional information are treated using an artificial neural network to produce a predicted value for the GI of the food product. For the sample set examined (n = 72) consisting of a variety of food types, r2 = 0.93 and the root mean square error of correlation (RMSEC) = 5 GI units. Twenty‐fold cross‐validation yields CVR2 = 0.89, indicating good predictive ability for samples outside the calibration set. The relative standard deviation of the method is 6.6%. This method is rapid and low cost relative to in vivo testing. Due to good ability to predict in vivo GI, it may be a valuable screening tool for determining the relative effect of food ingredients on the glycemic index of a food product. 相似文献
794.
Ruth Callaway Andrew P. Shinn Suzanne E. Grenfell James E. Bron Gavin Burnell Elizabeth J. Cook Margaret Crumlish Sarah Culloty Keith Davidson Robert P. Ellis Kevin J. Flynn Clive Fox Darren M. Green Graeme C. Hays Adam D. Hughes Erin Johnston Christopher D. Lowe Ingrid Lupatsch Shelagh Malham Anouska F. Mendzil Thom Nickell Tom Pickerell Andrew F. Rowley Michele S. Stanley Douglas R. Tocher James F. Turnbull Gemma Webb Emma Wootton Robin J. Shields 《水产资源保护:海洋与淡水生态系统》2012,22(3):389-421
795.
Pedro L. Rivera William T. Li Sumail Bhogal Jonathan B. Mandell Rebekah Belayneh Margaret L. Hankins John T. Payne Rebecca J. Watters Kurt R. Weiss 《Veterinary and comparative oncology》2023,21(3):559-564
Twenty-four dogs with OS underwent limb amputation. Serum, OS tumour, and normal bone were harvested at time of surgery. RNA was extracted and gene expression was performed using quantitative polymerase chain reaction (qPCR). Tissue and blood copper concentrations were also determined with spectrophotometry. Compared to bone, tumour samples had significantly higher expressions of antioxidant 1 copper chaperone (ATOX1, p = .0003). OS tumour copper levels were significantly higher than that of serum (p < .010) and bone (p = .038). Similar to our previous observations in mouse and human OS, dog OS demonstrates overexpression of genes that regulate copper metabolism (ATOX1), and subsequent copper levels. Dogs with OS may provide a robust comparative oncology platform for the further study of these factors, as well as potential pharmacologic interventions. 相似文献