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21.
Although a principal source of energy and protein for millions of the world's poorest people, the nutritional value of sorghum (Sorghum bicolor L. Moench) is diminished because of low digestibility of grain protein and starch. To address this problem, we analyzed the properties of two sorghum lines that have a common pedigree but differ in digestibility. Consistent with results based on a ruminal fluid assay, the protein and starch of one line (KS48) was more thoroughly digested than that of the other (KS51) using in vitro assays based on pepsin and α-amylase. The indigestibility of KS51 relative to KS48 was shown to be due to (i) a greater abundance of disulfide-bonded proteins; (ii) presence in KS51 of non-waxy starch and the accompanying granule-bound starch synthase; and (iii) the differing nature of the protein matrix and its interaction with starch. The current findings suggest that each of these factors should be considered in efforts to enhance the nutritional value of sorghum grain.  相似文献   
22.
A case-based program called ATLes (Adaptive Teaching and Learning Environments) was designed for use in a systemic pathology course and implemented over a four-year period. Second-year veterinary students working in small collaborative learning groups used the program prior to their weekly pathology laboratory. The goals of ATLes were to better address specific learning objectives in the course (notably the appreciation of pathophysiology), to solve previously identified problems associated with information overload and information sorting that commonly occur as part of discovery-based processes, and to enhance classroom discussion. The program was also designed to model and allow students to practice the problem-oriented approach to clinical cases, thereby enabling them to study pathology in a relevant clinical context. Features included opportunities for students to obtain additional information on the case by requesting specific laboratory tests and/or diagnostic procedures. However, students were also required to justify their diagnostic plans and to provide mechanistic analyses. The use of ATLes met most of these objectives. Student acceptance was high, and students favorably reviewed the online 'Content Links' that made useful information more readily accessible and level appropriate. Students came to the lab better prepared to engage in an in-depth and high-quality discussion and were better able to connect clinical problems to underlying changes in tissue (lesions). However, many students indicated that the required time on task prior to lab might have been excessive relative to what they thought they learned. The classroom discussion, although improved, was not elevated to the expected level-most likely reflecting other missing elements of the learning environment, including the existing student culture and the students' current discussion skills. This article briefly discusses the lessons learned from ATLes and how similar case-based exercises might be combined with other approaches to enhance and enliven classroom discussions in the veterinary curriculum.  相似文献   
23.
Nutritional programming represents the mechanism through which broodstock feeding strategies have lifelong effects on the offspring generation. The objective of this study was to determine whether supplementing rainbow trout, Oncorhynchus mykiss broodstock diets with choline and methionine affects offspring growth performance. Experimental diets were produced by top-dressing a commercial broodstock diet with (a) 12,000 ppm methionine, (b) 7,400 ppm choline, (c) 12,000 ppm methionine and 7,400 ppm choline, or (d) water (control). Six rainbow trout families were fed experimental diets beginning 18 months post-hatch through spawning; the offspring consumed a commercial diet. The broodstock diet did not affect maternal body weight, body condition, egg size, or egg yield (p > .05). Eggs from choline-treated broodstock contained 10% more choline than control eggs (p < .05). Offspring from choline-treated broodstock were smaller than controls at 146 days post-hatch (dph) (p < .05). At the final harvest (439 dph), offspring from the control broodstock weighed 12–18% less than offspring from broodstock consuming the supplemented diets (p < .05). However, there was a significant diet-by-family interaction on offspring growth (p < .05); supplemented diets improved performance in three of the six broodstock families. These findings indicate that supplementing broodstock diets with methionine and choline causes a nutritional programming effect that benefits growth in offspring.  相似文献   
24.
Over time, evidence-based veterinary medicine (EBVM) should integrate with normal clinical practice. Also, clinical knowledge increases with EBVM, reducing the need for information in one area and allowing veterinarians to explore new areas of specialty or cutting-edge advances in the profession. Textbooks, journals, veterinary conferences, and web sites provide nearly unlimited information about EBVM for the practicing veterinarian to help with the transition to EBVM use in daily practice life. EBVM should continue to change and improve how we, as veterinarians, provide the best available care to our clients and patients.  相似文献   
25.
The word nontraditional in the context of this article implies those modalities not normally taught in veterinary medical schools. This word has the same definition of Complementary and Alternative Medicine (CAM) as put forth by the Harvard medical school. CAM is a field of medicine that has enjoyed a recent increase in popularity in both human and equine medicine, particularly in regard to pain management. Some of the more recognized modalities include acupuncture, herbalism, and homeopathy. A brief discussion regarding the theory, scientific evidence and use of these therapies in the treatment of pain will be discussed.  相似文献   
26.
The effects of the phenolic compounds catechin (Cat), quercetin (Qer), and resveratrol (Res) present in red wine on early atherosclerosis were studied in hamsters. Hamsters (n = 32) were divided into 4 groups of 8 and fed an atherogenic diet for 12 weeks. They received by force-feeding 7.14 mL/(kg of body wt.day) Cat, Qer, or Res in water [2.856 mg/(kg of body wt.day) for Cat and 0.1428 mg/(kg of body wt.dday) for Qer and Res], mimicking a moderate consumption of alcohol-free red wine (equivalent to that supplied by the consumption of about two glasses of red wine per meal for a 70 kg human), or water as control. Plasma cholesterol concentration was lower in groups that consumed phenolics than in controls. The increase in plasma apolipoprotein (Apo) A1 concentration was mainly due to Cat (26%) and Qer (22%) and to a lesser extent, but nonsignificantly, Res (19%). Apo-B was not affected. Plasma antioxidant capacity was not improved, and there was no sparing effect on plasma vitamins A and E. Plasma iron and copper concentrations were not modified nor were liver super oxide dismutase and catalase activities. A sparing effect of Qer on liver glutathione peroxidase activity appeared, whereas Cat and Res exhibited a smaller effect. Aortic fatty streak area was significantly reduced in the groups receiving Cat (84%) or Qer (80%) or Res (76%) in comparison with the controls. These findings demonstrate that catechin, quercetin, and resveratrol at nutritional doses prevent the development of atherosclerosis through several indirect mechanisms.  相似文献   
27.
The aim of this study was to evaluate the antiatherosclerotic effect of commercially available phenolic-rich extracts from grape seeds (ExGrape seeds, EGS; grape seed extract, GSE) and marc (ExGrape total, EGT) in cholesterol-fed hamsters and to investigate possible operating mechanisms. These extracts fed at a moderate dose mimicking two glasses of red wine per meal reduced plasma cholesterol (-11% on average) but did not affect plasma antioxidant capacity of hamsters. The extracts prevented the development of aortic atherosclerosis by 68% (EGS), 63% (EGT), and 34% (GSE). Elsewhere, in an ex vivo experiment using rat aortic rings, EGS (7 microg/mL) induced 77% endothelium-dependent relaxation, whereas EGT and GSE (30 microg/mL) induced 84 and 72%, respectively. These results suggests that phenolic extracts from grape seeds and marc are beneficial in inhibiting atherosclerosis by indirect mechanism(s).  相似文献   
28.
Virtual patients have become an interesting alternative in medical education. Due to increasing demands regarding theoretical and clinical teaching and to improve an interdisciplinary approach, a new blended learning concept including virtual patients was developed and implemented in the veterinary curriculum of the Freie Universität Berlin. In the presented project, three virtual patients from the field of canine reproduction were developed. They focus on pregnancy diagnosis with suspected luteal insufficiency, pyometra and benign prostatic hyperplasia, respectively. The results of an evaluation by veterinary students of the 7th semester showed a high acceptance of virtual patients in a blended learning reproduction module in the interdisciplinary lectures. Students especially preferred videos, such as video lectures, hands-on videos and animations as well as a glossary for background information, to successfully and autonomously work on a virtual case. The content covered by the new modules that were developed in the context of this project is part of a spiral curriculum; they will be revised and enhanced during the clinical year.  相似文献   
29.
Summary A significant correlation among chromosome number, chloroplast number and pollen grain size was observed using interspecific hybrids (2n=30,60), Arachis hypogaea (2n=40), A. stenosperma (PI 338280) (2n=20), A. batizocoi (PI 468329) (2n=20) and A. villosulicarpa Hoehne (PI 336984) (2n=20), representing four ploidy groups. Both chloroplast number in guard cells and pollen grain size were found to be positively correlated with ploidy, and provided a reliable method to distinguish diploid, triploid, tetraploid and hexaploid plants from each other regardless of their taxonomic backgrounds. These methods in combination with root-tip chromosome counts enabled us to confirm ploidy determinations on all three dissue layers, L1, L2 and L3 (guard cells, microsporocytes and root meristematic cells, respectively), and to detect the chimeric nature of some colchicine-treated tissue culture-derived plants. Screening pollen grains by size and the detection of highly stainable and viable, 30-chromosome pollen grains have enhanced the use of triploid hybrids in peanut breeding programs.  相似文献   
30.
Simple nonlethal blood culture methodology, an alternative to euthanasia for diagnosing systemic bacterial infections in fish, is described. Blood was extracted from the caudal vein of 20 individuals of five fish species, incubated in brain-heart infusion broth, and then plated onto enriched blood agar. Nine of these fish were subsequently euthanized and necropsied for confirmatory tissue cultures. Five species of bacteria were isolated from the blood cultures from nine fish, and the tissue culture results in euthanized, necropsied fish agreed with the blood culture results in all cases. All the fish that were not euthanized survived for 24 hr, although two heavily parasitized fish subsequently died.  相似文献   
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