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النتائج 271 - 280 من 517
Location of open reading frames coding for equine herpesvirus type-1 glycoproteins with homology to gE and gI of herpes simplex virus
1991
Elton, D.M. | Bonass, W.A. | Killington, R.A. | Meredith, D.M. | Halliburton, I.W.
The DNA fragments representing the entire short unique region and part of the repeat sequences of the equine herpesvirus type-1 genome were cloned into plasmid vectors. The approximate positions of the junctions between the short unique region and the inverted repeats were then located by restriction endonuclease mapping. Two open reading frames coding for potential glycoproteins have been identified within the short unique region, using DNA sequence analysis. The predicted amino acid sequences of these open reading frames had extensive homology to the herpes simplex virus glycoproteins gE and gI and the related glycoproteins of pseudorabies virus and varicella-zoster virus.
اظهر المزيد [+] اقل [-]Effects of treatment with ticlopidine in heartworm-negative, heartworm-infected, and embolized heartworm-infected dogs
1991
Boudreaux, M.K. | Dillon, A.R. | Sartin, E.A. | Ravis, W.R. | Spano, J.S.
Ticlopidine hydrochloride was evaluated for its effectiveness in inhibiting platelet aggregation and serotonin release in 5 laboratory Beagles before and after heartworm implantation with 7 adult Dirofilaria immitis, and after embolization with 7 dead heartworms to mimic what happens after heartworm adulticide treatment. Five other laboratory Beagles, similarly implanted and embolized with heartworms, were used as nonmedicated controls. During the heartworm-negative stage, the dosage of ticlopidine that inhibited adenosine diphosphate (ADP)-induced platelet aggregation in 5 dogs by at least 50% after 5 days of treatment was 62 mg/kg of body weight once a day. In the same dogs implanted with 7 adult heartworms 21 days previously, mean (+/- SD) ticlopidine dosage required to obtain similar results was 71 (+/- 13) mg/kg given once daily. During the 21 days after dead heartworms were implanted in heartworm-infected dogs, mean ticlopidine dosage was 108 (+/- 35) mg/kg (range, 62 to 150 mg/kg). Ticlopidine treatment was associated with increased platelet numbers in all 5 dogs during the heartworm-negative stage and in 4 of 5 dogs during the heartworm implantation and heartworm embolization stages. Mean platelet volume tended to decrease as platelet numbers increased. At necropsy, gross and histologic pulmonary lesions were less severe in ticlopidine-treated dogs than in nonmedicated control dogs.
اظهر المزيد [+] اقل [-]Morphologic and morphometric study of the facial nerve in clinically normal adult dogs
1991
Braund, K.G. | Mehta, J.R. | Amling, K.A. | Toivio-Kinnucan, M.
A morphologic and morphometric study was carried out on the facial nerve: to determine normal histologic data in myelinated fibers of clinically normal young adult dogs; to establish reference values for mean fiber diameter, and to delineate the relative diameter frequency distribution curve. Few degenerative changes were observed in single teased-nerve fibers and semithin cross-sectional nerve preparations. Statistical difference was not observed between left and right facial nerves. The distribution of fiber diameters in the facial nerve was unimodal. Mean (+/- SD) fiber diameter of the facial nerve was 3.92 +/- 1.18 micromole. Approximately 89% of fibers in the facial nerve had diameter between 3 and 6 micromole. Fiber diameter ranged from 2 to 12 micromole; however, < 1% of fibers had diameter > 8 micromole.
اظهر المزيد [+] اقل [-]Case-control study of fowl cholera outbreaks in meat turkeys in California from August 1985 through July 1986
1991
Hird, D.W. | Carpenter, T.E. | Snipes, K.P. | Hirsh, D.C. | McCapes, R.H.
From Aug 1985 through July 1986, 720 meat turkey flocks on 160 California premises were monitored and outbreaks of fowl cholera (Pasteurella multocida) were investigated. Data from 43 outbreak (case) flocks were compared with data from 43 nonoutbreak (control) flocks. Outbreak flocks, compared with control flocks, were more likely to be located on premises with higher maximal bird capacity and history of fowl cholera outbreaks. The overall impression was that flocks in larger, newer, more intensively managed premises were at greater risk of fowl cholera outbreaks than were other flocks.
اظهر المزيد [+] اقل [-]In vitro characteristics of normal and dystrophic skeletal muscle from dogs
1991
Valentine, B.A. | Chandler, S.K. | Cummings, J.F. | Cooper, B.J.
Explants were prepared from skeletal muscle tissue from 5 nondystrophic pups and from 5 pups with X-linked muscular dystrophy; pups were 2 to 17 weeks old. A serial reexplant method resulted in optimal cell density with minimal fibroblast growth. Cultures were examined daily by use of phase-contrast microscopy; differentiated (postfusion) cultures were examined by electron microscopy. Moderate nuclear pleomorphism and cell clustering were observed in cultures of normal and dystrophic muscle cells. Cultures were maintained to 27 days after plating. Minimal myofilament synthesis was observed in multinucleate cells from nondystrophic and dystrophic pups, but spontaneous contraction of myotubes was not observed during this period. Differences in growth, fusion, or differentiation of myogenic cells into multinucleate cells and myotubes were not found between dystrophic and normal muscle.
اظهر المزيد [+] اقل [-]Effect of a passive heat and moisture exchanger on esophageal temperature in tumor-bearing dogs during whole-body hyperthermia
1991
Meyer, R.E. | Page, R.L. | Thrall, D.E.
The effect of a passive heat and moisture exchanger on tracheal and large airway temperature, as reflected by esophageal temperature at the thoracic inlet, was determined for 12 anesthetized and ventilated tumor-bearing dogs undergoing whole-body hyperthermia at 42 C. Delivered thermal dose to the esophagus and rectum during 120 minutes of whole-body hyperthermia was quantified as the thermal dose summary measure EQ43. The heat and moisture exchanger significantly increased esophageal EQ43 from 7.3 minutes to 12.1 minutes. Esophageal EQ43, however, remained lower than rectal EQ43. Although use of a heat and moisture exchanger improved esophageal temperature during whole-body hyperthermia, presumably through improved airway temperature, additional methods will be necessary to increase esophageal and airway temperature to the target value of 42 C.
اظهر المزيد [+] اقل [-]Preclinical evaluation of L-asparaginase and methotrexate administered at intermediate doses in dogs
1991
Bortnowski, H.B. | Rosenthal, R.C.
The role of L-asparaginase (L-ASP) in limiting signs of methotrexate (MTX) toxicosis was studied. Eight dogs were randomly allotted to 2 groups of 4 dogs. All dogs were given 400 IU of L-ASP/kg of body weight IM, on day 1. On day 10, group-1 dogs were given 3 mg of MTX/kg, IV, and group-2 dogs were given 6 mg of MTX/kg, IV. All dogs were given 400 IU of L-ASP/kg, IM, 24 hours later (on day 11). One group-2 dog was euthanatized on day 16 because of severe gastrointestinal signs that were unresponsive to treatment. A second dose of MTX, identical to that given on day 10, was given on day 20 to each surviving dog, followed by L-ASP on day 21. On day 67, the 7 surviving dogs were given 3 mg gf MTK/kg, IV. Adverse reactions observed were vomiting diarrhea, and weight loss. Gastrointestinal side effects of MTX were not attenuated with L-ASP and would be a serious limitation to use of MTX administered at an intermediate dose in the treatment of lymphoma in dogs.
اظهر المزيد [+] اقل [-]High sulfide concentrations in rumen fluid associated with nutritionally induced polioencephalomalacia in calves
1991
Gould, D.H. | McAllister, M.M. | Savage, J.C. | Hamar, D.W.
Nine 115- to 180-kg, hay-adapted, Holstein steers were fed an experimental diet with added sodium sulfate that induces polioencephalomalacia (PEM). Five calves developed the disease. Thiamine concentrations in blood, CSF, brain, and liver were not indicative of thiamine deficiency. The odor of hydrogen sulfide in eructated rumen gas was associated with the onset of PEM. Sulfide concentrations in rumen fluid were measured 1 or 2 times a week by 2 techniques. Sulfide concentrations progressively increased in all 9 calves after the feeding of the PEM-inducing diet commenced. The highest concentrations coincided with the onset of clinical signs of PEM and were significantly higher in the calves that developed PEM than in those that did not. This suggests that PEM can result from sulfide toxicosis following excess production of sulfide in the rumen.
اظهر المزيد [+] اقل [-]Effects of mechanical and pharmacologic manipulations on portal pressure, central venous pressure, and heart rate in dogs
1991
Swalec, K.M. | Smeak, D.D. | Brown, J.
Central venous pressure (CVP), portal pressure (PP), and heart rate (HR) were monitored in 6 female, sexually intact, middle-age Beagles during temporary portal vein obstruction, anesthetic recovery, abdominal bandaging, and propranolol administration. Intraoperative baseline PP was 7.3 mm of Hg (+/- 1.7 SD). Portal pressure was significantly increased throughout portal vein occlusion, but returned to baseline values 2 minutes after release of the ligature. Central venous pressure was significantly decreased throughout portal vein occlusion, but did not differ significantly from baseline values 3 minutes after release of the portal vein ligature. Portal pressure increased significantly (8 +/- 3.3 mm of Hg) over baseline values after application of an abdominal bandage; however, CVP did not change significantly. During postoperative monitoring, CVP and PP did not change significantly from respective 18-hour mean postoperative values in resting dogs. At 60 and 75 minutes after surgery, heart rate was significantly increased over the 18-hour mean. Portal pressure and CVP, respectively, were significantly increased over intraoperative baseline values in the first hour and the first 8 hours after surgery. Postoperative CVP and HR were significantly correlated. Individual measurements of PP in dogs that were abdominal pressing during barking or defecation were significantly increased (9 +/- 3 mm of Hg) above measurements taken after cessation of abdominal press. Portal pressure measurements in standing dogs decreased 7.5 +/- 2 mm of Hg, compared with measurements of the same dog in lateral recumbency. Central venous pressure was inaccurate in dogs performing abdominal press. Portal pressure did not decrease significantly from baseline after injection of propranolol (2 mg/kg, IV). Central venous pressure was significantly decreased at 2.5 and 3.0 hours after propranolol injection, and HR was significantly decreased from 1 to 3.5 hours after injection. Heart rate quickly returned to normal values if the dogs became excited. After propranolol administration, significant correlations were found between PP and HR, and between CVP and HR.
اظهر المزيد [+] اقل [-]Quantitative urinalysis in kittens from four to thirty weeks after birth
1991
Hoskins, J.D. | Turnwald, G.H. | Kearney, M.T. | Gossett, K.A. | Fakier, N.
To evaluate renal function and obtain reference values for measurements of urinary excretion of various substances, quantitative urinalysis was performed in healthy, growing kittens from 4 to 30 weeks after birth. Endogenous creatinine clearance, 24-hour urine protein excretion, and urine protein-to-creatinine ratio were determined. Additionally, fractional excretion to creatinine clearance was calculated for calcium, inorganic phosphorus, sodium, potassium, and chloride. Mean +/- SD endogenous creatinine clearance values (range, 3.80 +/- 0.48 to 4.74 +/- 0.61 ml/min/kg) were significantly (P < 0.0001) higher in kittens 9 to 19 weeks old, compared with younger (range, 1.39 +/- 0.85 to 3.59 +/- 0.86 ml/min/kg) and older kittens (range, 2.69 +/- 0.40 to 3.46 +/- 0.37 ml/min/kg). Mean values for all kittens for 24-hour urine protein excretion (range, 2.54 +/- 1.81 mg/kg at 4 weeks to 11.39 +/- 7.61 mg/kg at 14 weeks) and for urine protein-to-creatinine ratio (range, 0.14 +/- 0.03 to 0.34 +/- 0.18) varied from week to week of age. The urine protein-to-creatinine ratio in kittens greater than or equal to 9 weeks old correlated well (R2 = 0.861) with 24-hour urine protein excretion. Urinary fractional excretion of calcium, inorganic phosphorus, sodium, potassium, and chloride in kittens varied among age groups, being significantly (P < 0.01) different for potassium and calcium in young kittens (4 to 6 weeks) and older kittens (greater than or equal to 7 weeks).
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