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91.
A monoclonal antibody, K9BYU, was generated using Escherichia coli recombinant extracellular domain of canine neural-cell adhesion molecule (N-CAM) as an antigen. Immunoreactivity of K9BYU to insect cell recombinant canine N-CAM was demonstrated by Western blotting using Sf9 insect cells transfected with the canine N-CAM gene. In Western blotting against canine brain tissue, K9BYU detected three isoforms of N-CAM that correspond to three major isoforms of human and mouse N-CAM (N-CAM-120, -140, and -180). From these results, K9BYU was considered to be a useful tool for research of canine N-CAM.  相似文献   
92.
Two hundred crossbred cattle (Bos indicus x Bos taurus) were supplemented with 2% Tasco (Ascophyllum nodosum) in a commercial finishing facility to evaluate marbling score, USDA quality grade, sensory traits, and retail display shelf life. Treatment animals (n = 100) received a steam-rolled corn (Zea mays)-based diet containing 2% Tasco meal (DM basis), for 14 d beginning at d 45 of the finishing period and again 14 d before slaughter. Control animals (n = 100) received a steam-rolled corn (Zea mays)-based diet without Tasco at identical feeding periods. Carcasses from Tasco-fed cattle exhibited greater marbling scores (P = 0.003) than controls. There were no treatment effects (P > 0.05) on sensory, shear, or purge attributes of striploin or inside round steaks with the exception of inside round steaks from Tasco animals having a greater initial tenderness (P = 0.03) and lower off-flavor score (P = 0.002) than control steaks. The LM samples from Tasco-fed cattle had a greater percentage of ether extractable fat (P = 0.001) and lower percentage of protein (P = 0.001) than controls. Inside round samples from treated animals exhibited a greater percentage of moisture (P = 0.03) than control steaks. Visual lean color of striploin steaks was not affected by Tasco supplementation (P = 0.26); however, steaks from Tasco-treated animals were more uniform and had less discoloration and browning than those from controls (P = 0.005, 0.04, and 0.05, respectively). Inside round visual scores and instrument values reflected similar treatment responses (P < 0.05), with a majority of the effects on muscle redness (CIE a*, hue angle) and measures of discoloration. Tasco steaks were generally more red and less discolored during extended postmortem aging and retail exposure (P < 0.05). The results from this study indicate that short-term supplementation of 2% Tasco meal in feedlot cattle increases carcass quality and prolonged retail shelf life.  相似文献   
93.
94.
Restriction fragment length polymorphism analysis of PCR products (PCR-RFLP) and sequencing of the variable region of the p104 and PIM genes was performed on samples obtained from South African T. parva parasites originating from cattle on farms with suspected theileriosis and from buffalo. p104 and PIM PCR-RFLP profiles similar to those of the T. parva Muguga stock, an isolate that causes ECF in Kenya, were obtained from three of seven cattle samples collected on a farm near Ladysmith in KwaZulu-Natal Province. Amino acid sequences of the p104 and PIM genes from two of these samples were almost identical to the T. parva Muguga p104 and PIM sequences. This result supports findings from a recent p67 study in which p67 alleles similar to those of the T. parva Muguga stock were identified from the same samples. While these results suggest the presence of a cattle-derived T. parva parasite, reports of cattle-to-cattle transmission could not be substantiated and ECF was not diagnosed on this farm. Although extensive diversity of p104 and PIM gene sequences from South African T. parva isolates was demonstrated, no sequences identical to known cattle-type p104 and PIM alleles were identified from any of the buffalo T. parva samples analyzed. 'Mixed' PIM alleles containing both cattle- and buffalo-type amino acid motifs were identified for the first time, and there appeared to be selection of cattle-type and 'mixed'-type PIM sequences in the cattle samples examined.  相似文献   
95.
96.
Fourteen 4- to 18-month-old vaccinated Greyhounds (10 males, 4 females) from three kennels in southern Ireland presented over a 2-year period with acute or insidious onset neurological signs. Head tilting, ataxia, recumbency, circling, and blindness were commonly observed, and animals were dull, dehydrated, and had lost weight. Hematologic and biochemical parameters reflected dehydration but were otherwise unremarkable. Microscopic examination revealed severe diffuse and focal gliosis and gemistocytosis accompanied by mononuclear cell perivascular cuffing in caudate nucleus and cortical gray matter of the cerebrum and in the periventricular gray matter of the anterior brainstem. Milder lesions were noted in the caudal brainstem, cranial spinal cord, and in the molecular layer of the cerebellum. This was accompanied by a lymphocyte and plasma cell infiltration of the cerebral and cerebellar meninges. Demyelination, neuropil necrosis, neuronophagia, and vasculitis were not observed. No inclusion bodies, fungi, or protozoal cysts were seen. Additional serologic and molecular pathology tests also failed to determine a cause, suggesting that these cases may represent a previously undiagnosed condition in the dog.  相似文献   
97.
Our objectives were to 1) establish ionised calcium (ICa), C-terminal PTH and biologically active PTH (intact molecule) concentrations in blood from normal horses, 2) examine the stability of ionised calcium and acid-base values in stored equine heparinised blood and serum and 3) check the applicability of the formulas based on these parameters in certain disease states. Mean +/- s.d. % ionised calcium in heparinised blood of normal Warmbloods was 51 +/- 2.7 (n = 20) of total calcium, range 1.45-1.75 mmol/l (n = 15) at Michigan State University and 1.43-1.69 mmol/l (n = 20) at Utrecht University. Mean +/- s.d. EDTA plasma concentration for intact +/PTH in normal horses measured 0.6 +/- 0.3 pmol/l (n = 11). Both mean serum and the heparinised blood ionised calcium concentrations changed (not significantly) after 102 h storage at room temperature. Six cycles of freezing and thawing did not affect serum ionised calcium concentration significantly. Ionised calcium concentration and pH in heparinised blood of 20 normal Warmbloods were used to calculate the regression equation for the prediction of the adjusted ionised calcium concentration to a pH of 7.4. The linear regression equation found was: adjusted plasma ICa at pH 7.4 mmol/l = -6.4570 + 0.8739 x (measured pH) + 0.9944 x (measured ICa mmol/l). By means of this formula, mean adjusted ionised calcium concentration in heparinised blood calculated was 100% of the actual value given by the analyser in the normal horses. When using this formula in horses with colic or diarrhoea, mean adjusted ionised calcium concentration was underestimated by 0.2 and 0.3%, respectively. Furthermore, to adjust the measured ionised calcium concentration in heparinised blood to a pH of 7.4 in healthy as well as in 2 groups of diseased horses 2 formulas with a good prediction are now available.  相似文献   
98.
Typing of Salmonella enterica subsp. enterica serovar Mbandaka isolates   总被引:2,自引:0,他引:2  
Recently, Salmonella enterica subsp. enterica serovar Mbandaka (S. Mbandaka) has gained some importance in the epidemiology of salmonellosis in Poland. Since biotyping, resistance typing, and plasmid profiling were insufficient for strain differentiation, genome macrorestriction by means of pulse-field gel electrophoresis (PFGE) was applied and proved to be the method of choice in S. Mbandaka epidemiological studies. XbaI and BcuI macrorestriction produced 15 and 14 pulse-field profiles (PFP), respectively, but in the case of each enzyme one profile was prevalent. When macrorestriction profiles were combined, a total 24 patterns were found. Based on the similarity of the profiles, four clonal lineages were identified. One clonal lineage contained the majority of poultry, feed and human isolates. Poultry was concluded to be an important source of S. Mbandaka for humans in Poland. Complementary use of various typing techniques improved efficacy of epidemiological studies giving possibility to subdivide S. Mbandaka into 35 types and the index of discrimination reached 0.947.  相似文献   
99.
100.
OBJECTIVE: To assess morphologic and metabolic abnormalities in dogs with early left ventricular dysfunction (ELVD) induced by rapid right ventricular pacing (RRVP). ANIMALS: 7 Beagles. PROCEDURE: Plasma carnitine concentrations were measured before and after development of ELVD induced by RRVP. At the same times, transvenous endomyocardial biopsy was performed, and specimens were submitted for determination of myocardial carnitine concentrations and histologic, morphometric, and ultrastructural examination. RESULTS: In 4 dogs in which baseline plasma total carnitine concentration was normal, RRVP induced a decrease in myocardial total and free carnitine concentrations and an increase in myocardial esterified carnitine concentration. In 3 dogs in which baseline plasma total carnitine concentration was low, plasma and myocardial carnitine concentrations were unchanged after pacing. Structural changes associated with pacing included perinuclear vacuolization in 3 dogs. Morphometric analyses indicated there was a decrease in myofiber cross-sectional diameter and area following pacing. Electron microscopy revealed changes in myofibrils and mitochondria following pacing. CONCLUSIONS AND CLINICAL RELEVANCE: Results indicated that moderate to severe alterations in myocyte cytoarchitecture are present in dogs with ELVD induced by RRVP and that in dogs with normal plasma carnitine concentrations, myocardial carnitine deficiency may be a biochemical marker of ELVD. Results also indicated that transvenous endomyocardial biopsy can be used to evaluate biochemical and structural myocardial changes in dogs with cardiac disease.  相似文献   
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