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排序方式: 共有187条查询结果,搜索用时 15 毫秒
51.
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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Dr. Gebhard Schüler 《Water, air, and soil pollution》1990,54(3):435-444
Several experimental series are described to investigate the compensation effects of buffer substances against acid deposition in forest ecosystems. Laboratory tests with different basic buffer substances showed, that their neutralization capacity depend more on the particle size fractions than on the contents of bases. Comparisons of the effects of dolomite, enriched volcanic silicate rock meal and volcanic silicate rock meal as well as dolomite suspensions and coarsely ground dolomite in field experiments confirmed the laboratory tests to a large extent. The following short-term effects were ascertained: (1) the pH in the mineral soil could not be influenced within 2 yr, and (2) the stock of accumulated acids in the mineral soil decreased in dependency on the kind of buffer substance. The results of these experiments show after a short time, that compensation of acid deposition in forest ecosystems by basic buffer substances is justified as soil protection and strongly necessary. 相似文献
54.
Dr. Gebhard Schüler 《Water, air, and soil pollution》1990,54(1):435-444
Several experimental series are described to investigate the compensation effects of buffer substances against acid deposition in forest ecosystems. Laboratory tests with different basic buffer substances showed, that their neutralization capacity depend more on the particle size fractions than on the contents of bases. Comparisons of the effects of dolomite, enriched volcanic silicate rock meal and volcanic silicate rock meal as well as dolomite suspensions and coarsely ground dolomite in field experiments confirmed the laboratory tests to a large extent. The following short-term effects were ascertained: (1) the pH in the mineral soil could not be influenced within 2 yr, and (2) the stock of accumulated acids in the mineral soil decreased in dependency on the kind of buffer substance. The results of these experiments show after a short time, that compensation of acid deposition in forest ecosystems by basic buffer substances is justified as soil protection and strongly necessary. 相似文献
55.
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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Marta E Bull Douglas G Gebhard Wayne A F Tompkins Suzanne Kennedy-Stoskopf 《Veterinary immunology and immunopathology》2002,84(3-4):181-189
Free-ranging African lion (Panthera leo) peripheral blood mononuclear cells (PBMC) were examined using flow cytometry and antibodies developed for use in the domestic cat to determine if phenotypic changes occurred in lion lymphocytes as a result of feline immunodeficiency virus (FIV) infection. The percentage of CD8 cells from lion peripheral blood was considerably lower than in the domestic cat. Lions with elevated levels of CD8+ cells were typically infected with FIV, similar to observations in the domestic cat. Antibodies against the alpha chain of the CD8 receptor (monoclonal antibody (mAb) 3.357) did not react consistently in all lions examined. Flow cytometric analysis determined that approximately 82 and 80% of the animals from Kruger and Hluhluwe-Umfolozi National Parks in South Africa reacted with the monoclonal antibody against the alpha chain of CD8 receptor, while only 17% of the lions in Etosha National Park in Namibia cross-reacted with the CD8alpha chain. There was no apparent correlation between FIV status and CD8alpha chain reactivity. The relative isolation of Etosha from the other two parks could explain the marked difference in CD8alpha chain expression and suggests that lions similar to other mammalian species demonstrate polymorphic expression of the CD8alpha chain (197). 相似文献
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59.
ELASTOGRAPHIC EVALUATION OF NATURALLY OCCURING TENDON AND LIGAMENT INJURIES OF THE EQUINE DISTAL LIMB
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Meghann Lustgarten W. Rich Redding Raphael Labens Weston Davis Thomas M. Daniel Emily Griffith Gabriela S. Seiler 《Veterinary radiology & ultrasound》2015,56(6):670-679
Compression elastography is an ultrasonographic technique that estimates tissue strain and may have utility in diagnosing and monitoring soft tissue injuries in the equine athlete. Recently, elastography has been proven to be a feasible and repeatable imaging modality for evaluating normal tendons and ligaments of the equine distal forelimb. The purposes of this prospective study were to investigate the ability of elastography to detect spontaneously occurring lesions of equine tendons and ligaments diagnosed with magnetic resonance imaging (MRI) and gray‐scale ultrasound (US) and to characterize the differences in the elastographic appearance of acute vs. chronic injuries. Fifty seven horses with a total of 65 lesions were evaluated. Images were assessed quantitatively and qualitatively. Acute lesions were found to be significantly softer (P < 0.0001) than chronic lesions (P < 0.0001) and the stiffness of lesions increased with progression of healing (P = 0.0138). A negative correlation between lesion hypoechogenicity and softness was appreciated with more hypoechoic lesions appearing softer (P = 0.0087) and more hyperechoic regions harder (P = 0.0002). A similar finding occurred with increased signal intensity on short tau inversion recovery (STIR) and proton density (PD) MRI sequences correlating with increased softness on elastography (P = 0.0164). Using US and MRI as references, commonly encountered soft tissue injuries of the equine distal limb could be detected with elastography. However, elastography was limited for detecting small, proximal injuries of the hindlimb proximal suspensory ligament. Elastographic evaluation of equine tendons and ligaments may allow better characterization of lesion chronicity and severity, and sequential examinations may optimize lesion management, rehabilitation, and return to training. 相似文献
60.
Karsak M Gaffal E Date R Wang-Eckhardt L Rehnelt J Petrosino S Starowicz K Steuder R Schlicker E Cravatt B Mechoulam R Buettner R Werner S Di Marzo V Tüting T Zimmer A 《Science (New York, N.Y.)》2007,316(5830):1494-1497
Allergic contact dermatitis affects about 5% of men and 11% of women in industrialized countries and is one of the leading causes for occupational diseases. In an animal model for cutaneous contact hypersensitivity, we show that mice lacking both known cannabinoid receptors display exacerbated allergic inflammation. In contrast, fatty acid amide hydrolase-deficient mice, which have increased levels of the endocannabinoid anandamide, displayed reduced allergic responses in the skin. Cannabinoid receptor antagonists exacerbated allergic inflammation, whereas receptor agonists attenuated inflammation. These results demonstrate a protective role of the endocannabinoid system in contact allergy in the skin and suggest a target for therapeutic intervention. 相似文献