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排序方式: 共有3765条查询结果,搜索用时 15 毫秒
91.
da Rocha AC da Silva AB de Brito AB Moraes HL Pontes AP Cé MC do Nascimento VP Salle CT 《Avian diseases》2002,46(3):749-753
Sixty-three Escherichia coli strains isolated from broilers with respiratory problems were examined for virulence factors, hemolysin synthesis ability, motility, hemagglutination capacity, operon pap presence, colicin production, and serum resistance. The capacity to hemagglutinate guinea pig erythrocytes was found in 53 (84.1%) of the samples, but only 30 (47.6%) agglutinated chicken erythrocytes. D-mannose-sensitive hemagglutination against guinea pig erythrocytes was found in 19 (30.2%) samples and against chicken erythrocytes, in 15 (23.8%) samples, whereas the D-mannose-resistant hemagglutination with guinea pig erythrocytes was found in 34 (54%) samples, and 13 of these (20.6%) showed this characteristic against chicken erythrocytes. Operon pap, P fimbria codifier, was detected in 26 samples in a total of 34 D-mannose-resistant samples. Colicin production was observed in 55 (87.3%) of the strains, and 41.8% presented V colicin production. Of the samples analyzed, 56 (88.9%) presented serum resistance, six (9.5%) were intermediate, and only one (1.6%) was sensitive to the action of the complement. The diversity of virulence profiles detected in the samples in this study explains in part the multifactorial characteristics of avian colibacillosis. 相似文献
92.
OBJECTIVE: To evaluate the possible association between facet joint geometry and intervertebral disk degeneration in German Shepherd Dogs. ANIMALS: 25 German Shepherd Dogs and 11 control dogs of similar body weight and condition. PROCEDURE: Facet joint angles in the caudal portion of the lumbar region of the vertebral column (L5-S1) were measured by use of computed tomography, and the intervertebral discs were evaluated microscopically. The relationship between facet joint geometry and disk degeneration was evaluated by use of statistical methods. RESULTS: German Shepherd Dogs had significantly more facet joint tropism than control dogs, but an association with disk degeneration was not found. However, German Shepherd Dogs had a different facet joint conformation, with more sagittally oriented facet joints at L5-L6 and L6-L7 and a larger angle difference between the lumbar and lumbosacral facet joints, compared with control dogs. CONCLUSIONS AND CLINICAL RELEVANCE: A large difference between facet joint angles at L6-L7 and L7-S1 in German Shepherd Dogs may be associated with the frequent occurrence of lumbosacral disk degeneration in this breed. 相似文献
93.
Sánchez-Cordón PJ Hervás J Chacón de Lara F Jahn J Salguero FJ Gómez-Villamandos JC 《Avian diseases》2002,46(2):485-492
In this paper we report on an outbreak of reovirus, herpesvirus (Pacheco disease), and/or mycosis infection (Aspergillus spp. and Zygomyces spp.) affecting a batch of young African grey parrots (Psittacus erithacus), with 80% morbidity and 30% mortality. Study material was taken from five birds (four dead and one euthanatized) with a range of clinical symptoms (depression, diarrhea, respiratory symptoms). Diagnosis was confirmed by immunohistochemical detection of avian reovirus, electron microscopy, and virus isolation. Viral antigen of reovirus was detected mainly in large mononuclear cells in the bursa of Fabricius and the spleen, pancreas epithelial cells, and circulating cells; lymphoid organs displayed the largest number of immunopositive cells and severe lymphocyte depletion. Bacteriologic study was negative. Reovirus infection was common in all birds studied, whereas Pacheco disease and mycosis were found in only some, suggesting that reovirus could be the initial cause triggering the outbreak and facilitating infection by other agents and their swift spread through the batch. 相似文献
94.
Isolation and characterization of immortalized porcine aortic endothelial cell lines 总被引:6,自引:0,他引:6
Carrillo A Chamorro S Rodríguez-Gago M Alvarez B Molina MJ Rodríguez-Barbosa JI Sánchez A Ramírez P Muñoz A Domínguez J Parrilla P Yélamos J 《Veterinary immunology and immunopathology》2002,89(1-2):91-98
Primary porcine endothelial cells have a limited life span in culture. After four to five passages, they tend to de-differentiate and eventually reach senescence. The aim of this work was to establish immortalized porcine aortic endothelial cell lines (AOCs) to facilitate in vitro studies of different pathological process involving the endothelium. Primary porcine aortic endothelial cells (PAECs) were transfected with a plasmid containing the SV40 genome and selected on the basis of morphological and phenotypical features. Flow cytometry analysis demonstrated uptake of acetylated low density lipoproteins (Ac-LDL) and constitutive expression of SLA class I, CD29, CD31, CD41/61, CD80/86, CD46, SWC3, and LAMP-1 antigens by all analyzed lines and showed little differences to primary cells. The functional similarity between primary and immortalized endothelial cells was demonstrated in a cytotoxicity assay using a human natural killer cell line (NKL) as effector. The AOCs cell lines should be valuable tools for in vitro study of the human immune response against pig endothelial cells. In addition, they would be very useful to gain insight in the pathogenesis of some viral haemorrhagic diseases of pig such as African swine fever (ASF) or classical swine fever (CSF). 相似文献
95.
Chateau H Degueurce C Jerbi H Crevier-Denoix N Pourcelot P Audigié F Pasqui-Boutard V Denoix JM 《Veterinary research》2002,33(4):371-382
The objective of this study was to assess the effects of asymmetric placement of the foot on the three-dimensional motions of the interphalangeal joints. Four isolated forelimbs were used. Trihedrons, made of three axes fitted with reflective markers, were screwed into each phalanx. They allowed to establish a local frame associated with each bone and thus to define the spatial orientation of the phalanges. The limbs were then placed under a power press, and subjected to compression with gradually increasing force (from 500 to 6 000 N). The procedure was performed in neutral position and with the lateral or medial part of the foot raised by a 12 degrees wedge. Flexion, collateromotion (passive abduction/adduction) and axial rotation of the interphalangeal joints were measured using a cardan angle decomposition according to the principle of the "Joint Coordinate System" described by Grood and Suntay. Raising the lateral or medial part of the hoof induced collateromotion (about 5.6 degrees +/- 0.8) and axial rotation (about 6.5 degrees +/- 0.5) of the distal interphalangeal joint. The proximal interphalangeal joint underwent axial rotation (about 4.7 degrees +/- 0.5 at 6 000 N) and slight collateromotion. Both interphalangeal joints underwent collateromotion in the direction of the raised part of the foot (i.e., narrowing of the articular space on the side of the wedge), whereas axial rotation occurred in the direction opposite to the raised part of the foot. These results confirm the functional importance of interphalangeal joint movements outside the sagittal plane. In particular they demonstrate the involvement of the proximal interphalangeal joint in the digital balance. These data are helpful for the identification of biomechanical factors that may predispose to interphalangeal joint injury. Also the data may be of use for the rational decision making with respect to exercise management and corrective shoeing of the lame horse. 相似文献
96.
Tischendorf F Möckel P Schöne F Plonné M Jahreis G 《Journal of animal physiology and animal nutrition》2002,86(9-10):313-325
The effect of conjugated linoleic acid (CLA) on blood lipids [total cholesterol, high-density lipoprotein (HDL), low-density lipoprotein (LDL) and triacylglycerols (TAG)] and the fatty acid distribution of the lipoprotein fractions, backfat, muscle fat, and liver lipids were examined in an experiment with two groups of 40 pigs [Pietrain x (Landrace x Large White)] each. The 20 female and 20 male castrated pigs of each group were fed with isoenergetic and isonitrogenous diets supplemented with either 20 g/kg rapeseed oil (control) or 20 g/kg CLA-TAG. The CLA preparation contained 54.2% pure CLA consisting of approximately two-thirds cis,trans/trans,cis-isomers and one-third trans,trans-isomers. The fatty acids of lipoproteins, backfat, muscle lipids and liver lipids were analysed by gas chromatograph (GC). CLA supplementation did not significantly influence blood lipids and the LDL to HDL ratio. In the CLA-fed pigs the very low-density lipoprotein (VLDL) contained higher saturated fatty acid (SFA) concentrations at the cost of the monounsaturated fatty acids (MUFA). The percentage of polyunsaturated fatty acids (PUFA) remained unchanged. The highest CLA content was analysed in VLDL (4.00%) followed by LDL (2.78%) and HDL (1.45%). The ratio of cis,cis to trans,trans isomers increased from VLDL over LDL to HDL. The content of SFA, probably in backfat and muscle lipids, increased whereas the part of MUFA decreased as a result of reduced Delta9-desaturase activity. The percentage of PUFA (without CLA) was higher in backfat of the control group in accordance with the dietary PUFA supply. This shift in the fatty acid distribution was not observed in the liver lipids. In all the three tissues analysed, the CLA-fed pigs had a significantly increased CLA content: the highest increase was in the backfat (5.65%), followed by liver lipids (2.41%), and muscle lipids (1.47%). An isomer-specific accumulation was observed for cis,cis-CLA isomers in muscle, and for trans,trans-CLA isomers in backfat. We conclude that CLA supplementation results in a higher SFA content in backfat and muscle lipids but not in liver lipids. There is a discrimination of the trans-10, cis-12 isomer and the trans,trans isomers in the formation of the cell membranes. 相似文献
97.
Montané J Marco I Manteca X López J Lavín S 《Journal of veterinary medicine. A, Physiology, pathology, clinical medicine》2002,49(2):93-98
Delayed acute capture myopathy is the term used to describe the clinical syndrome observed in three roe deer captured by drive-nets and transported to an enclosure for scientific purposes. The animals died 48 h, 60 h and 8 days after being captured. The simultaneous deaths coincided with a previous episode of deliberate human disturbance. The histopathological findings were indicative of acute myopathy and myoglobinaemic nephrosis. These could be related to an ataxic myoglobinuric syndrome brought on by capture and transport operations. The lack of clinical signs and negative prognosis indicators in the period between capture and just before death. the absence of gross muscular lesions in the animal that died after 8 days post-capture, the simultaneous deaths of animals captured at different times and the evidence of deliberate human disturbance in the enclosure are suggestive of death triggered by a second stress episode. 相似文献
98.
Well-known plant poisonings such as 'dunsiekte' (seneciosis) and 'jaagsiekte' (crotalariosis) of horses in southern Africa are briefly reviewed. Relatively unfamiliar mycotoxicoses such as stachybotryotoxicosis and perennial rye grass staggers and potentially occurring exotic intoxications such as equine nigropallidal encephalomalacia and ergot alkaloid poisoning are also discussed. This article is aimed at informing the southern African equine practitioner about probable poisonings that might occur locally in horses. 相似文献
99.
ABSTRACT Big-vein disease occurs on lettuce worldwide in temperate conditions; the causal agent has been presumed to be Lettuce big-vein virus (LBVV), genus Varicosavirus, vectored by the soilborne fungus Olpidium brassicae. Recently, the role of LBVV in the etiology of big-vein disease has been questioned because a second soilborne virus, Mirafiori lettuce virus (MiLV), genus Ophiovirus, has been found frequently in big-vein-affected lettuce. LBVV and MiLV, detectable and distinguishable by enzyme-linked immunosorbent assay using specific antisera, were tested for their ability to be transmitted from lettuce to lettuce by mechanical inoculation of sap extracts, or by zoospores of O. brassicae, and to cause big-vein disease. Both viruses were mechanically transmissible from lettuce to herbaceous hosts and to lettuce, but very erratically. LBVV was transmitted by O. brassicae but lettuce infected with only this virus never showed symptoms. MiLV was transmitted in the same manner, and lettuce infected with this virus alone consistently developed big-vein symptoms regardless of the presence or absence of LBVV. With repeated mechanical transmission, isolates of both viruses appeared to lose the ability to be vectored, and MiLV appeared to lose the ability to cause big-vein symptoms. The recovery of MiLV (Mendocino isolate, from Cali-fornia) from stored O. brassicae resting spores puts the earliest directly demonstrable existence of MiLV at 1990. 相似文献
100.