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51.
52.
Hillebrand S Schwarz M Winterhalter P 《Journal of agricultural and food chemistry》2004,52(24):7331-7338
Anthocyanins from blood orange [Citrus sinensis (L.) Osbeck] juices were isolated and purified by means of high-speed countercurrent chromatography and preparative high-performance liquid chromatography. Structures of the pigments were then elucidated by electrospray ionization multiple mass spectrometry and nuclear magnetic resonance (NMR) spectroscopy. The major anthocyanins of the juice were characterized as cyanidin 3-glucoside and cyanidin 3-(6"-malonylglucoside). Furthermore, six minor anthocyanins were detected and identified as cyanidin 3,5-diglucoside, delphinidin 3-glucoside, cyanidin 3-sophoroside, delphinidin 3-(6"-malonylglucoside), peonidin 3-(6"-malonylglucoside), and cyanidin 3-(6"-dioxalylglucoside). The occurrence of the latter compound in blood oranges is reported here for the first time, together with full NMR spectroscopic data. Further investigations revealed the presence of four anthocyanin-derived pigments, which are formed through a direct reaction between anthocyanins and hydroxycinnamic acids during prolonged storage of the juice. These novel pyranoanthocyanins were identified as the 4-vinylphenol, 4-vinylcatechol, 4-vinylguaiacol, and 4-vinylsyringol adducts of cyanidin 3-glucoside through comparison of their mass spectrometric and chromatographic properties with those of synthesized reference compounds. 相似文献
53.
Hilbert A Reith P Brockmann SO Tyczka J Fischer SF Piechotowski I Wagner-Wiening C Winter CH Bendak J Meier C Spengler D Miller T Kleine-Albers C Renner C Koepsel U Hensler E Henning K Fröhlich A Conraths FJ Kramer M 《Berliner und Münchener tier?rztliche Wochenschrift》2011,124(7-8):295-302
In 2008 and 2009, two consecutive outbreaks of Q fever in humans were recorded in the district of Freudenstadt, northern Black Forrest, Baden-Württemberg, Germany. In 2008, a total of 41 persons from a single local community fell ill and were found infected with Coxiella burnetii. Although comprehensive diagnostic and epidemiological outbreak investigations were conducted and control measures taken which included vaccination of ruminants at risk in three parts of the affected community, re-occurrence of the disease in 2009 with further 29 confirmed human Q fever cases could not be prevented. While the origin of infection of the first outbreak was probably a flock of 550 sheep moved in the surrounding of the affected villages, the source of infection for the consecutive outbreak in 2009 could not be identified. It seems possible that meadows contaminated with infectious placenta or birth fluids represented the sources of infection. 相似文献
54.
Objective: To describe the anatomic features of the equine trochanteric bursa and to evaluate 4 techniques for bursa centesis. Study Design: Prospective, randomized design. Animals: Equine cadavers (n=2) and 20 live horses. Methods: The trochanteric bursae of 2 equine cadavers were injected with latex to identify the boundaries of the bursae. Four techniques for centesis of the trochanteric bursa were evaluated by attempting to inject dye into both trochanteric bursae of 20 live horses. Techniques included injection of the bursa with the limb‐bearing weight and injection with the limb nonweight bearing and supported on a block, with or without ultrasonographic guidance of the needle. Ultrasonographic guidance of the needle was performed with or without the use of a guide channel attached to the ultrasound probe. Each of the 4 techniques was used to inject 10 bursae. The region of the bursa was dissected after horses were euthanatized to determine the location of the dye. Results: The trochanteric bursa was most successfully injected with the limb positioned caudally with the foot on a block, even though topographic landmarks for centesis were more difficult to identify when the limb was in this position. The highest incidence of success was achieved when the needle was inserted using ultrasonographic guidance with the foot in a Hickman block. Conclusion: Positioning the limb caudally with the foot nonweight bearing and on a block facilitated centesis of the trochanteric bursa. 相似文献
55.
ABSTRACT: Transmission from pet rats and cats to humans as well as severe infection in felids and other animal species have recently drawn increasing attention to cowpox virus (CPXV). We report the cloning of the entire genome of cowpox virus strain Brighton Red (BR) as a bacterial artificial chromosome (BAC) in Escherichia coli and the recovery of infectious virus from cloned DNA. Generation of a full-length CPXV DNA clone was achieved by first introducing a mini-F vector, which allows maintenance of large circular DNA in E. coli, into the thymidine kinase locus of CPXV by homologous recombination. Circular replication intermediates were then electroporated into E. coli DH10B cells. Upon successful establishment of the infectious BR clone, we modified the full-length clone such that recombination-mediated excision of bacterial sequences can occur upon transfection in eukaryotic cells. This self-excision of the bacterial replicon is made possible by a sequence duplication within mini-F sequences and allows recovery of recombinant virus progeny without remaining marker or vector sequences. The in vitro growth properties of viruses derived from both BAC clones were determined and found to be virtually indistinguishable from those of parental, wild-type BR. Finally, the complete genomic sequence of the infectious clone was determined and the cloned viral genome was shown to be identical to that of the parental virus. In summary, the generated infectious clone will greatly facilitate studies on individual genes and pathogenesis of CPXV. Moreover, the vector potential of CPXV can now be more systematically explored using this newly generated tool. 相似文献
56.
Pancreatic disorders in dogs and cats are recognized with increasing frequency, and abdominal ultrasonography has assumed an important role in their diagnosis. The normal pancreas is a small, inconspicuous organ of comparable echogenicity to surrounding mesentery and may be difficult to identify. Therefore, knowledge of anatomic landmarks such as portal vein and contributing vessels, duodenum, and stomach is necessary to facilitate identification and examination. Pancreatic diseases and abnormalities frequently investigated by means of ultrasonography include pancreatitis, pseudocysts, abscesses, neoplastic lesions, and nodular hyperplasia. Disorders less commonly seen include exocrine pancreatic insufficiency, pancreatolithiasis, congenital anomalies, and pancreatic edema. Unfortunately, ultrasonographic findings in various pancreatic disorders overlap, and incidental findings or age-related changes may mimic pancreatic disease. On the other hand, pancreatic disorders may not cause changes in ultrasonographic appearance. Ultrasonographic findings, therefore, have to be judged in light of signalment, history, and laboratory data. Cytology or histopathology may be needed to establish a definite diagnosis. Despite these limitations, ultrasonography is useful in diagnosing pancreatic disease, guiding aspirates and biopsies, and monitoring response to treatment. 相似文献
57.
荷兰瓦格林根大学园艺所通过对水果和盆栽植物在温和性气候下的生长研究,发现散射光对作物生长有一定的促进作用. 温室中散射光的制造和使用在位于赤道附近的国家中已经非常普遍.种植者使用特殊的,可以制造散射光的塑料薄膜来提高种植产量,同时避免灼伤作物.散射光意味着光向各个方向分散,同时在一个区域内是均匀分布. 相似文献
58.
微藻在生态系统的结构和功能中具有极为重要的作用,而传统光学人工镜检方法对微藻种类鉴别具有较大的难度。本研究将微藻的光学图像进行了采样,并结合国内外专家对微藻鉴定的经验知识,制作了微藻图像数据集,并进行了数据增强处理。借助深度学习的原理和方法,构建了基于卷积神经网络结构的深度学习模型(AlexNet),对模型进行了训练,并利用5折交叉验证方法确保模型的稳定性。结果表明,模型的训练精度可达到98.78±0.98%,测试精度达85.46±0.23%,达到了预期效果。利用AlexNet模型训练得到的参数,对预留的280个样本图像进行实际测试,7个藻种的平均精确度、平均召回率和平均F1 Score分别为0.832,0.844和0.833。表明深度学习方法是鉴定微藻的一种有效方法。 相似文献
59.
Silke Schmitz Stephanie Hill Dirk Werling Karin Allenspach 《Veterinary immunology and immunopathology》2013,151(1-2):168-172
Trefoil factors (TFF) are small peptides produced by goblet cells, which are crucial for epithelial restitution. In humans with inflammatory bowel disease (IBD), TFF expression is up-regulated as part of an unspecific repair mechanism. The goal of this study was to assess TFF gene expression in the gastrointestinal tract from dogs with IBD compared to healthy controls. Preliminary assessment by PCR revealed TFF1 and 3 expression in the small and large intestine, whereas TFF2 was amplified only in the stomach. Subsequent RT-qPCR (with relative quantification against 3 reference genes) on endoscopic duodenal (IBD n = 22, healthy controls n = 18) and colonic (IBD n = 12, controls n = 11) biopsies revealed that TFF1 expression was significantly up-regulated in the duodenum from IBD dogs (Mann–Whitney p = 0.001), whereas TFF3 expression was significantly lower in IBD colon compared to controls (t-test p = 0.018).This study demonstrates evidence for dysregulation of TFF gene expression in canine IBD. Up-regulation of TFF1 could signify ectopic expression as a compensatory repair-mechanism, whereas down-regulation of TFF3 could contribute to defective epithelial barrier function, respectively. Whether this is a cause or consequence of IBD could not be established. 相似文献
60.
Silke Hecht W. H. Adams M. A. Cunningham I. F. Lane N. E. Howell 《Veterinary radiology & ultrasound》2013,54(2):114-121
Effective teaching of veterinary radiology can be challenging in a traditional classroom environment. Audience response systems, colloquially known as “clickers,” provide a means of encouraging student interaction. The purpose of this study was to compare student performance and course evaluations before and after using the Classroom Performance System? in the third‐year (fifth semester) didactic radiology course at the University of Tennessee College of Veterinary Medicine. Overall student performance was assessed by comparing median numeric final course grades (%) between years without and with use of the Classroom Performance System?. Grades of students were determined for individual instructors’ sections. Student evaluations of the radiology course were compared for the years available (2007–2010). Student interactions were also evaluated subjectively by instructors who used the Classroom Performance System?. There was a significant difference (p = 0.009) between the median student grade before (2005 – 2008, median 82.2%; interquartile range 77.6–85.7%; range 61.9–95.5%) and after use of the classroom performance system (2009–2010, median 83.6%; interquartile range 79.9–87.9%; range 68.2–93.2%). There was no statistically significant difference in median student grades for individual instructors over the study period. The radiology course student evaluation scores were significantly higher in years where the Classroom Performance System? was used in comparison to previous years (P = 0.019). Subjectively, students appeared more involved when using clickers. Findings indicated that the Classroom Performance System? may be a useful tool for enhancing veterinary radiology education. 相似文献