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排序方式: 共有196条查询结果,搜索用时 95 毫秒
91.
Kuhnle GG Dell'Aquila C Aspinall SM Runswick SA Mulligan AA Bingham SA 《Journal of agricultural and food chemistry》2008,56(21):10099-10104
Dietary phytoestrogens may be involved in the occurrence of chronic diseases. Reliable information on the phytoestrogen content in foods is required to assess dietary exposure and disease risk in epidemiological studies. However, existing analyses have focused on only one class of these compounds in plant-based foods, and there is only little information on foods of animal origin, leading to an underestimation of intake. This is the first comprehensive study of phytoestrogen content in animal food. We have determined the phytoestrogen content (isoflavones: biochanin A, daidzein, formononetin, genistein, and glycitein; lignans: secoisolariciresinol and matairesinol; coumestrol; equol; enterolactone; and enterodiol) in 115 foods of animal origin (including milk and milk-products, eggs, meat, fish, and seafood) and vegetarian substitutes using liquid chromatography-mass spectrometry (LC-MS) with (13)C-labeled internal standards. Phytoestrogens were detected in all foods analyzed; the average content was 20 microg/100 g of wet weight (isoflavones, 6 microg/100 g; lignans, 6 microg/100 g; equol, 3 microg/100 g; and enterolignans, 6 microg/100 g). In infant soy formula, 19 221 microg/100 g phytoestrogens were detected (compared to 59 microg/100 g in non-soy formula). Our study shows that all foods analyzed contained phytoestrogens and most foods (except for fish, seafood, and butter) contained mammalian phytoestrogens (enterolignans and equol). This is the first comprehensive study of phytoestrogen content of foods of animal origin and will allow for a more accurate estimation of exposure to dietary phytoestrogens. 相似文献
92.
Elizabeth Urban-Gedamke Megan Conkling Peter J. McCarthy Paul S. Wills Shirley A. Pomponi 《Marine drugs》2021,19(10)
Production of sponge-derived bioactive compounds in vitro has been proposed as an alternative to wild harvest, aquaculture, and chemical synthesis to meet the demands of clinical drug development and manufacture. Until recently, this was not possible because there were no marine invertebrate cell lines. Recent breakthroughs in the development of sponge cell lines and rapid cell division in improved nutrient media now make this approach a viable option. We hypothesized that three-dimensional (3-D) cell cultures would better represent how sponges function in nature, including the production of bioactive compounds. We successfully cultured sponge cells in 3-D matrices using FibraCel® disks, thin hydrogel layers, and gel microdroplets (GMDs). For in vitro production of bioactive compounds, the use of GMDs is recommended. Nutrients and sponge products rapidly diffuse into and out of the 3-D matrix, the GMDs may be scaled up in spinner flasks, and cells and/or secreted products can be easily recovered. Research on scale-up and production is in progress in our laboratory. 相似文献
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Taxonomic differences in responsiveness to chemosensory irritants are prevalent among avian and mammalian species and represent a major obstacle to the development of general vertebrate repellents. We evaluated the effect of ortho-aminoacetophenone (OAP), a potent avian repellent, on ingestive behavior of two rodent species, Prairie vole (Microtus ochrogaster), Deer Mouse (Peromyscus maniculatus Wagn.), and an avian species, European starling (Sturnus vulgarus L.) utilizing similar experimental conditions to facilitate interspecies comparisons. All three species avoided OAP-treated food. Apple consumption by voles was decreased from a baseline of theoretical zero% by OAP (0·01–10·0 ml liter−1), P <0·000 01, while mice avoided all but the lowest concentration of OAP (0·01−10 ml liter−1), P <0·000 01. A repellent should elicit avoidance behavior prior to the animal having physical contact with the commodity, ideally producing aversion via volatile cues rather than through direct contact. Therefore, we utilized two delivery methods for presentation of the test solutions to evaluate the repellency of OAP in the presence and absence of direct contact. Apple consumption by birds following exposure to OAP by either direct contact or volatile cues differed from a baseline of theoretical zero% consumption, P < 0·001. When birds had access to OAP through both direct and volatile exposures, reduction in apple consumption by European starlings was greater than observed following contact with the compounds volatile cues alone, P < 0·03. These findings argue against a major role for olfaction or nasotrigeminal chemoreception in avoidance of OAP-treated food. Instead, taste or oral trigeminal chemoreception appear to mediate responding. 相似文献
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Ford W. Bell Jeffrey S. Klausner David W. Hayden Elizabeth M. Lund Barbara B. Liebenstein Daniel A. Feeney Shirley D. Johnston Jan L. Shivers Charles M. Ewing William B. Isaacs 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》1995,9(3):149-153
Serum and seminal plasma concentrations or activities of acid phosphatase (AP), prostate specific antigen (PSA), and canine prostate specific esterase (CPSE) were measured in normal dogs, dogs with benign prostatic hyperplasia (BPH), dogs with bacterial prostatitis, and dogs with prostatic carcinoma to determine if these assays would be of value in differentiating dogs with prostatic carcinoma from normal dogs, and dogs with other prostatic disorders. In addition, tissue sections of prostatic adenocarcinomas were stained with antiprostatic AP, anti-CPSE, and anti-PSA antibodies to determine if these would be suitable immunohistochemical markers of prostatic carcinoma. Prostate-specific antigen was not detected in canine serum or seminal plasma. Serum and seminal AP activities did not differ significantly between normal dogs and those with prostatic diseases, or among dogs with different prostatic disorders. Serum CPSE activities were significantly higher in dogs with BPH than in normal dogs. Mean serum CPSE activities in dogs with BPH, bacterial prostatitis, and prostatic carcinoma were not significantly different from each other. Slight to moderate immunohistochemical staining of canine prostatic adenocarcinomas was noted for prostatic AP and PSA; most tumors did not stain for CPSE. These results show that proteins of prostatic origin appear in the serum of dogs as a result of prostatic pathology, especially BPH. Canine prostatic adenocarcinoma does not appear to be associated with significant increases in CPSE or AP activities, possibly because of down-regulation of these enzymes by prostatic carcinoma cells. It is also possible that failure to detect significant differences resulted from limited statistical power for some groups and pairwise analyses because of the small number of dogs evaluated. 相似文献
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Anastasia MW Cooper Kristopher Silver Jianzhen Zhang Yoonseong Park Kun Yan Zhu 《Pest management science》2019,75(1):18-28
RNA interference (RNAi) is an endogenous, sequence‐specific gene‐silencing mechanism elicited by small RNA molecules. RNAi is a powerful reverse genetic tool, and is currently being utilized for managing insects and viruses. Widespread implementation of RNAi‐based pest management strategies is currently hindered by inefficient and highly variable results when different insect species, strains, developmental stages, tissues, and genes are targeted. Mechanistic studies have shown that double‐stranded ribonucleases (dsRNases), endosomal entrapment, deficient function of the core machinery, and inadequate immune stimulation contribute to limited RNAi efficiency. However, a comprehensive understanding of the molecular mechanisms limiting RNAi efficiency remains elusive. Recent advances in dsRNA stability in physiological tissues, dsRNA internalization into cells, the composition and function of the core RNAi machinery, as well as small‐interfering RNA/double‐stranded RNA amplification and spreading mechanisms are reviewed to establish a global understanding of the obstacles impeding wider understanding of RNAi mechanisms in insects. © 2018 Society of Chemical Industry 相似文献