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排序方式: 共有163条查询结果,搜索用时 62 毫秒
41.
Kristine M Smith Paul Calle Bonnie L Raphael Stephanie James Robert Moore Denise McAloose Eric Baitchman 《Journal of zoo and wildlife medicine》2006,37(1):44-48
Medical records of three male and three female callitrichids of four species (Leontopithecus chrysopygus, Leontopithecus rosalia, Callithrix argentata argentata, Callithrix kuhlii) diagnosed with cholelithiasis were reviewed. Ages of affected animals at the time of diagnosis ranged from 2-14 yr. Definitive antemortem diagnosis of cholelithiasis was made in four of the six cases. Chronic weight loss, lethargy, and weakness were seen in all cases. Chronic intermittent diarrhea was seen in three cases. Icterus and abnormal gait were each present in two of the animals. Hematologic and serum biochemical abnormalities included leukocytosis in five cases, elevated bilirubin (direct and indirect) in four cases, and anemia in four cases. Radiographic evidence of choleliths was observed in three cases. Surgical removal of choleliths was successfully performed on two animals. Full necropsies were performed on all cases, and choleliths were believed to contribute to morbidity in all cases. However, inflammatory bowel disease was determined to be the primary cause of weight loss and mortality in at least three animals. All choleliths analyzed were pigment stones, two being primarily composed of cystine. 相似文献
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Pathology of fatal West Nile virus infections in native and exotic birds during the 1999 outbreak in New York City, New York 总被引:9,自引:0,他引:9
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Proteases that reside in cellular membranes apparently wield water to hydrolyze the peptide bonds of substrates despite their water-excluding environment. Although these intramembrane proteases bear little or no sequence resemblance to classical water-soluble proteases, they have ostensibly converged on similar hydrolytic mechanisms. Identification of essential amino acid residues of these proteases suggests that they use residue combinations for catalysis in the same way as their soluble cousins. In contrast to classical proteases, however, the catalytic residues of intramembrane proteases lie within predicted hydrophobic transmembrane domains. Elucidating the biological functions of intramembrane proteases, identifying their substrates, and understanding how they hydrolyze peptide bonds within membranes will shed light on the ways these proteases regulate crucial biological processes and contribute to disease. 相似文献
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Philipe A. Leo Camila I. Amaral Willian H. M. Santos Matheus V. L. Moreira Leticia B. de Oliveira Erica A. Costa Mauricio Resende Raphael Wenceslau Roselene Ecco 《Journal of veterinary diagnostic investigation》2021,33(3):605
We investigated the occurrence and pathologic findings of transmissible viral proventriculitis (TVP) associated with the chicken proventricular necrosis virus (CPNV) in commercial broiler chickens in southeastern Brazil. Seventy-three broilers, 25–36 d old, with a history of reduced growth, were referred to our veterinary pathology services from 2013 to 2017. Broilers were clinically examined, weighed, and euthanized for postmortem examination. Broilers of different ages with proventricular histologic lesions were positive for CPNV by RT-PCR; however, the intensity of histologic lesions was higher among 33-d-old animals, and viral RNA detection was more frequent among those that were 28 d old. In the proventriculi of 35 of 73 (48%) broilers, lesions were characterized by glandular epithelial necrosis, lymphoplasmacytic and histiocytic infiltrates, and metaplasia of glandular epithelium to ductal epithelium. In 24 of 73 (36%) broilers with histologic TVP-compatible lesions, CPNV was detected by RT-PCR for the viral protein 1 (VP1) gene. Broilers with histologic lesions were lighter than expected compared to the Cobb 500 standard weight. TVP has not been reported previously in broiler chickens in Brazil, to our knowledge. 相似文献
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Jeana Pereira da Silva Sheila Canevese Rahal Maria Cristina Reis Castiglioni Raphael Augusto Baldissera Gonçalves Danuta Pulz Doiche Anneke Moresco Maria Jaqueline Mamprim Luiz Carlos Vulcano 《Anatomia, histologia, embryologia》2020,49(4):541-549
This study aimed to evaluate normal features of the heart and lower respiratory tract in toco toucans by means of radiography and helical computed tomography (CT) scanner. Fifteen healthy adult toco toucans (Ramphastos toco), 10 females and 5 males, average body mass of 650 g were studied. CT examination as well as right lateral and ventrodorsal radiographic examinations of the coelomic cavity were performed under chemical restraint. Heart, lungs, air sacs, trachea and syrinx were analysed. The mean values of heart length, heart width and thoracic cavity in radiographs were, respectively, 23.76 mm, 25.94 mm and 48.87 mm. In both X-rays and CT scans, the lung parenchyma had honeycomb-like pattern. The topographic areas of the anterior and posterior air sacs were visualized as dark and air-filled spaces in X-rays. On CT evaluation, the air sacs occupied a larger area in the coelomic cavity compared to X-ray. In the lateral radiographic view, the cervical part of the trachea was positioned more ventrally in the transition from cervical to thoracic regions showing a V-shaped appearance. In all CT planes was visible division of the trachea into the right and left main bronchi at the level of 3rd thoracic vertebra. The syrinx was difficult to visualize in X-rays, but on CT it was easily identified in axial slice. In conclusion, the normal features of toco toucan's heart and lower respiratory tract that were determined on X-rays and CT scans are useful to compare with sick toco toucans, as well as other bird species. 相似文献
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以9种豆科牧草为试材,在缺磷砂土上研究施用Ca(H2PO4)2后对其产酸量的影响.结果表明:Lupinus albus,Lupinus lutens和Biserrula pelecinus施磷需求量比Cicer aritimum,Vicia faba,Medicago polgmorpha,Ornithopus sativus和Trifolium subterraneum低,而Lupinus angustifolius需求量最高.当增施磷肥,使其达到中度缺磷水平时,比酸度有所增加,但进一步增施磷肥则使植株产酸量减少,在几种植物中,C.arietinum产酸量最高,B.pelecinus最低.比酸度与过量阳离子、灰碱、钙和镁等浓度有关.在不考虑施磷和植物品种的情况下,植物产酸总量与植株地上部分过量阳离子总量恰好一致;在施磷量不同的情况下,豆科植物产酸量主要由其吸收阳离子和阴离子的差异决定. 相似文献
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Practical diets with essential oils of plants activate the complement system and alter the intestinal morphology of Nile tilapia 下载免费PDF全文
Gustavo M. R. Valladão Sílvia U. Gallani Gabriela Pala Raphael B. Jesus Suzana Kotzent Jaqueline C. Costa Thiago F. A. Silva Fabiana Pilarski 《Aquaculture Research》2017,48(11):5640-5649
The effect of the essential oils (EOs) of peppermint, Mentha piperita L., and tea tree, Melaleuca alternifolia (Maiden & Betche) Cheel, on the haematological, biochemical, and immunological parameters and intestinal morphology of Nile tilapia, Oreochromis niloticus L., was evaluated. Fish (58.09 ± 5.87 g) were fed 100 mg/kg and 250 mg/kg of each EO and sampled on days 7, 14, 30 and 60 after starting supplementation. The haematological and biochemical parameters were not altered by the supplementation of EOs compared to the control (p > .05). With regard to the immunological parameters, the activation of the complement system of fish fed 250 mg/kg peppermint and 100 mg/kg and 250 mg/kg tea tree EOs were significantly higher compared to the control after 60 days of feeding (p < .05). The complement system plays an essential role in innate immunity and contributes significantly to the acquired immune response; thus, its activation through supplementation with EOs is promising for the formulation of nutritional additives in aquaculture. Regarding intestinal morphology, fish fed 250 mg/kg tea tree EO presented higher villus size compared to all other groups (p < .05), which represents a healthier gut. These fish present a larger intestinal surface, which can result in better absorption and utilization of the nutrients. Based on the responses found in this study, both EOs were considered promising for the formulation of feed additives for Nile tilapia. 相似文献