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1.
AIM: To assess the benefit of inducing emesis in dogs that have ingested rodenticide bait containing brodifacoum (BDF), by determining the amount of BDF in bait recovered from the vomitus relative to the estimated amount consumed.

METHODS: Between 2014 and 2015 samples of vomitus from seven dogs that ingested rodenticide baits containing BDF were submitted by veterinarians in New Zealand. All seven dogs had been given apomorphine by the veterinarian and vomited within 1 hour of ingesting the bait. Some or all of the bait particles were retrieved from each sample and were analysed for concentrations of BDF using HPLC. Based on estimations of the mass of bait consumed, the concentration of BDF stated on the product label, and the estimated mass of bait in the vomitus of each dog, the amount of BDF in the vomited bait was calculated as a percentage of the amount ingested.

RESULTS: For five dogs an estimation of the mass of bait ingested was provided by the submitting veterinarian. For these dogs the estimated percentage of BDF in the bait retrieved from the vomitus was between 10–77%. All dogs were well after discharge but only one dog returned for further testing. This dog had a normal prothrombin time 3 days after ingestion.

CONCLUSIONS AND CLINICAL RELEVANCE: The induction of emesis within 1 hour of ingestion can be a useful tool in reducing the exposure of dogs to a toxic dose of BDF. The BDF was not fully absorbed within 1 hour of ingestion suggesting that the early induction of emesis can remove bait containing BDF before it can be fully absorbed.  相似文献   

2.
倾斜圆盘勺式玉米精密排种器的试验研究   总被引:13,自引:5,他引:13  
为与铲式成穴器的结构特点相适应,选择倾斜圆盘勺式玉米精密排种器作为打穴播种机的排种机构。在分析分种勺结构特点和分种性能的基础上,通过试验确定了排种器倾角和转速对不同玉米种子分种性能的影响,并采用机械优化设计的方法对参数进行了优化组合。  相似文献   
3.
以植物叶蛋白浓缩物为材料,用胰蛋白酶在不同条件下对其进行水解。结果表明,胰蛋白酶作用于植物叶蛋白,其最佳水解温度为40℃;最佳水解pH值为9;水解程度随酶量和反应时间增加而增加;各种不同种类的植物叶蛋白在相同条件下被胰蛋白酶水解的程度基本一致,证明了植物叶蛋白易被动物体内蛋白酶分解。  相似文献   
4.
Inhalt Mit histologischen und histochemischen Methoden wird der Nebenhoden des Schweines in 6 von kranial nach kaudal aufeinanderfolgende Regionen (Segmente) unterteilt. Die Segmente 1 bis 3 rind im Kopf, die Segmente 4 und 5 im Körper des Nebenhodens lokalisiert. Segment 6 bildet den Schwanzabschnitt. Segment 1 besitzt das höchste Epithel, Segment 6 den großten Querschnitt. Spermatozoen werden in nennenswerter Anzahl nur in den Segmenten 3 bis 6 angetroffen. In den Segmenten 1,4,5 und 6 ist das Epithel gebuchtet; in den Faltentälern trägt es typische Stereocilien, auf den Faltenkänzmen dominieren Äquivalentbilder für eine apokrine Extrusion. Die Stereocilien in den Segmenten 2 and 3 verhalten sich histochemisch anders als im restlichen Nebenhoden. Segment 5 ist der lipidreichste Abschnitt des gesamten Canalis epididymidis und die einzige Region, in der sich auch Glykogen nachweisen läßt. Alle Zylinderzellen des Nebenhodens enthalten viel saure Phosphatase im supranuklearen Abschnitt (Golgi-Region); β-D-Glucuronidase massiert sich in Segment 6 und wird sonst nur im basalen Epitheldrittel von Segment 2 angetroffen. Contents (Histological and histochemical studies on the epithelium of the epididymis of adult boars). By means of histochemical and histological findings the porcine canalis epididymidis is divided into 6 regions (segments) following each other from cranial to caudal. Segments 1 to 3 are localized in the head portion, segments 4 and 5 in the body and segment 6 fro ms the tail of the epididymis. In segment 1 the epithelial height reaches a maximum. Segment 6 has the largest diameter. Noteworthy numbers of spermatozoa are found only within segments 3 to 6. In segments 1,4,5 and 6 the epithelium is more or less folded; in the valleys between these folds typical stereo cilia are seen, on the tips of these folds morphological equivalents of apocrine extrusion are dominating. Stereocilia in segments 2 and 3 differ histochemically from those of the remainder. Segment 5 is richest in lipids and the only one with positive glycogen reaction. All cylindrical cells of the epididymis contain large amounts of acid phosphatase in their supranuclear regions (Golgi area); β-D-glucuronidase is abundant in segment 6 and otherwise present only in the basal third of the epithelium in segment 2.  相似文献   
5.
Huitlacoche is the ethnic name of the young fruiting bodies of Ustilago maydis, a common parasite of maize. In Mexico and other Latin American countries, this fungus has been traditionally appreciated as a local delicacy. In this work a metallomics approach was used with the determination of eight elements in huitlacoche by electrothermal atomic absorption spectrometry as one facet of this approach. The results obtained indicated relatively lower concentrations of commonly analyzed metals, as referred to the data reported for other mushroom types. This effect was ascribed to different accessibilities of elements, depending on fungus substrate (lower from plant than from soil). Subcellular fractionation was accomplished by centrifugation of cell homogenates suspended in Tris-HCl buffer. Recoveries of the fractionation procedure were in the range of 71-103%. For six elements (Cr, Cu, Fe, Mn, Ni, and Pb), the mean relative contributions in cytosol, cell walls, and mixed membrane fraction were 50.7, 48.2, and 1.1% respectively. To attain the molecular weight distribution of compounds containing target elements as an additional aspect of the metallomics approach, the fungus extract (1% sodium dodecyl sulfate in Tris-HCl, 30 mmol L(-)(1), pH 7.0) was analyzed by size exclusion chromatography with UV and ICP-MS detection. With spectrophotometric detection (280 nm), the elution of high molecular weight compounds was observed in the form of one peak (MW > 10 kDa), and several lower peaks appeared at higher retention times (MW < 10 kDa). On ICP-MS chromatograms, a coelution of (59)Co, (63)Cu, (57)Fe, (202)Hg, (60)Ni, and (80)Se with the first peak on the UV chromatogram was clearly observed, indicating that a fraction of each element incorporated with high molecular weight compounds (12.7, 19.8, 33.7, 100, 19.4, and 45.8%, respectively, based on the peak area measurements). From a comparison of (80)Se and (33)S chromatograms (for sulfur analysis, the extract was obtained in the absence of SDS), both elements coeluted with the first UV peak, but their lower molecular weight compounds were apparently different. These findings may contribute to a better understanding of the accumulation of elements in mushrooms.  相似文献   
6.
Brazil nuts have been classified as the foodstuffs that contain the highest level of unadulterated selenium, an essential trace element that appears to prevent cancer. To date, characterization of the selenium species in brazil nuts has not yet been investigated. In this work, various sample preparation approaches, including microwave extractions and enzymatic treatments, are examined with the goal of species preservation and subsequent selenium speciation; of these approaches, an enzymatic treatment with Proteinase K proved most effective. High-performance liquid chromatography (HPLC) separation strategies and inductively coupled plasma mass spectrometry (ICP-MS) detection schemes will also be presented. Extracts are evaluated against available standards for the commercially obtainable seleno-amino acids, selenomethionine (SeMet), selenoethionine (SeEt), and selenocystine (SeCys); selenomethionine was demonstrated to be the most abundant of these seleno-amino acids. Further characterization of unidentified selenium-containing peaks is attempted by the employment of several procedures, including electrospray-mass spectrometry (ES-MS). A peptide structure was identified; however, this was considered a tentative proposal due to the large background produced by the extremely complicated brazil nut matrix.  相似文献   
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江西银杏叶黄酮类化合物含量及变化规律研究(Ⅰ)   总被引:2,自引:0,他引:2  
用分光光度法测定了从江西各地引种到江西农业大学的银杏其叶不同季节的黄酮类化合物含量,结果表明:不同种源的银杏叶黄酮含量差异较大;不同季节含量也有差异,以10月份为最高。  相似文献   
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