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101.
R D Ayl C G Couto A S Hammer S Weisbrode J G Ericson L Mathes 《Veterinary pathology》1992,29(5):386-390
By using flow cytometry, a retrospective analysis of the DNA content of 40 primary canine mast cell tumors and seven lymph nodes that contained metastatic mast cell tumor from 44 dogs of various breed, sex, and age was performed on formalin-fixed, paraffin-embedded samples of the tumors and nodes. These samples were chosen according to the following criteria: samples contained sufficient well-preserved tumor tissue in the paraffin block for processing, sufficient patient history data were available, clean and homogeneous cell suspensions were obtained after processing, and interpretable DNA histograms were produced on analysis. The ploidy data obtained were compared with the histopathologic grade, the anatomical site of occurrence, the clinical stage of the tumors, and the survival of the dogs. Over 70% (29/40) of the mast cell tumors were diploid. Three metastatic mast cell tumors in lymph nodes had the same ploidy status as their corresponding primary tumors. In five dogs, mast cell tumors from multiple sites in each dog displayed similar ploidy status. Of 26 dogs evaluated for survival times, 69% (18/26) had diploid tumors and 31% (8/26) had aneuploid tumors. When numbers of diploid versus aneuploid tumors were compared, no significant difference was found between any two grades, clinical stages, or anatomic sites. A significant difference (P = 0.02) was found, however, between aneuploid and diploid tumors when comparing Stage I and non-Stage I disease. The Kaplan-Meier survival plot indicated a tendency towards an increased survival within the first year in dogs with diploid versus aneuploid tumors (P = 0.06). 相似文献
102.
Two studies were conducted to determine whether sodium thiosulfate (THS) can estimate extracellular water (ECW) in beef cattle in conjunction with empty body water (EBW) estimation by urea space. Experiment 1 used 24 steers (366 kg) to determine the clearance parameters for THS and urea. Blood samples were taken over 1 h. A two-component curve, Y = A1ek1(t) + A2ek2(t), (t = hours after infusion) fit the clearance of both markers; intercepts (A1, A2) and clearance coefficients (k1, k2) were 44.8, 44.4, -25.8, and -2.24 mg/dL, respectively, for THS (r2 = .98, Sy.x = 2.72, animal effects removed and 24.4, 10.5, -21.7, and -.71 mg/dL, respectively, for urea (r2 = .98, Sy.x = 1.49). Sodium thiosulfate equilibrated with ECW 5 to 10 min after infusion. Experiment 2 consisted of 22 steers (483 kg) infused with a combination solution of 20% urea, 10% THS, and 4% sodium thiocyanate (SCN; equilibration time = 28 min); half the steers were implanted with estradiol. Empty body water increased with implantation (P less than .01). Extracellular water tended to increase in implanted steers as measured by THS (12 min, P = .14) and SCN (P = .10). The estimation of ECW at 12 min was not different (P greater than .2) from the SCN estimate at 28 min (SCN = 3.7 + .873 THS; r2 = .70; P less than .001). Sodium thiosulfate gave reasonable estimates of ECW (22 to 26% of BW) and required only 0- and 12-min blood samples.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
103.
Serum amyloid A protein concentration measured by radial immunodiffusion in Abyssinian and non-Abyssinian cats 总被引:1,自引:0,他引:1
S P DiBartola J A Reiter J B Cornacoff G J Kociba M D Benson 《American journal of veterinary research》1989,50(8):1414-1417
Serum amyloid A (SAA) protein concentration was determined by use of radial immunodiffusion (RID) in 4 groups of cats: Abyssinian cats with amyloidosis, healthy Abyssinian cats without clinical evidence of amyloidosis, hospitalized non-Abyssinian cats, and clinically normal non-Abyssinian cats. Mean SAA concentration in Abyssinian cats with amyloidosis was significantly (P = 0.05) higher than mean SAA concentration in healthy Abyssinian cats without clinical evidence of amyloidosis and in hospitalized non-Abyssinian cats. Mean SAA concentration in clinically normal non-Abyssinian cats was significantly (P = 0.05) lower than mean SAA concentration in healthy Abyssinian cats without clinical evidence of amyloidosis and in hospitalized non-Abyssinian cats. Affected and healthy Abyssinian cats, however, could not reliably be distinguished on the basis of SAA concentration, because of the wide range of SAA values in these 2 groups of cats. 相似文献
104.
Water-stable macro-aggregate size fractions (>2.0 mm, 1.0–2.0 mm, 0.5–1.0 mm and 0.25–0.5 mm) and non-aggregated soil from a sandy loam under long-term clover-based pasture and from grass pasture were analysed to determine the role of acid- and water-extractable carbohydrate C, total hyphal length, microbial biomass, organic C and total and mycorrhizal root length in stabilization of the aggregates. Aggregates were examined by scanning electron microscopy (SEM) and the particle-size distribution of the size fractions was also determined. Macro-aggregation increased under grass, relative to clover-based pasture; however, the properties of the aggregate fractions measured did not reflect this difference. Microbial-biomass C, extractable-carbohydrate C, hyphal length, total and mycorrhizal root length and organic C content of the soils were poorly correlated with macro-aggregation. Within the aggregates, the proportion of 250–1000-km sand was smaller and clay, silt and fine sand (20–250 μm) were greater relative to non-aggregated soil, suggesting that the >250-μm sand in the non-aggregated soil limited the stabilization of macro-aggregates. Under SEM, no enmeshment of aggregates by hyphae and roots was apparent. Although 50–160 m hyphae g?1 soil was found within the aggregates, calculations showed that on average only 5 to 13 lengths of hyphae were associated with each 250-μm cube of soil within the aggregates, and suggested little potential to stabilize the aggregates by enmeshing. On average, all >2.0-mm aggregates contained less than 3.6 mm of roots and less than 50% by weight of <2.0-mm aggregates contained a single length of root. The findings cast doubt about the role of hyphae and fine roots in the stabilization of macro-aggregates through an enmeshing mechanism in sandy soils. 相似文献
105.
M P Cunningham C G Brown M J Burridge S P Morzaria G M Urquhart 《Research in veterinary science》1989,46(1):90-94
Eight Friesian cross cows three months pregnant to a single Friesian bull were immunised against East Coast fever by infection with Theileria parva (Muguga) sporozoite stabilate and treatment with pyrrolidino-methyl tetracycline. They were challenged with the homologous stock four times before calving and a fifth time after calving, and resisted all five challenges which killed all of the five groups of five susceptible controls. Calves born to these hyperimmunised dams were fully susceptible on challenge with the same stabilate, as were susceptible cows from the same farm and their calves. In both instances the calves died three to seven days earlier than the cows which were approximately 10 times heavier. These results show that one- to two-month-old taurine calves from artificially immunised dams are not protected from experimental T parva sporozoite challenge and that there is no inherent calfhood resistance to East Coast fever. 相似文献
106.
K G Braund H S Steinberg A Shores J E Steiss J R Mehta M Toivio-Kinnucan K A Amling 《Journal of the American Veterinary Medical Association》1989,194(12):1735-1740
Six dogs with laryngeal paralysis had clinical, electrophysiologic, and pathologic evidence of a more generalized polyneuropathy. Three of the dogs were young Dalmatians, one was a young Bouvier des Flandres, and two were older, large-breed dogs. The results of this study suggest that laryngeal paralysis in dogs may frequently be one clinical sign of an underlying, more generalized polyneuropathy. Two forms of this generalized polyneuropathy may exist: an early form, as seen in young dogs with congenital or hereditary disease, and a delayed-onset form that is usually found in older dogs with so-called idiopathic laryngeal paralysis, some of which may have hypothyroidism. 相似文献
107.
Six bullmastiffs with congenital heart disease were evaluated over a three-year period. In all the cases the problem was shown to be dysplasia of the pulmonary valve. Five cases were male, one was female. All dogs available to follow-up developed signs of cardiac decompensation. Bullmastiffs must be added to the list of breeds in which valvular pulmonic stenosis is encountered frequently. 相似文献
108.
The effect of exploratory laparotomy on the serum and peritoneal haptoglobin concentrations of the pony. 总被引:1,自引:0,他引:1
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Serum haptoglobin concentration was used as an indicator of the acute phase response in ponies undergoing exploratory laparotomy. Preoperative, 1 h intraoperative, 3 h, 6 h, 12 h and 24 h postoperative blood samples and 48 h postoperative peritoneal fluid samples were obtained for haptoglobin analysis. A spectrophotometric assay based on cyanmethemoglobin binding capacity (CyanBC) was used to determine haptoglobin concentrations. The preoperative reference range for serum haptoglobin concentrations in these ponies was 25-60 mg CyanBC/dL. Intraoperative and 3 h postoperative blood samples had decreased haptoglobin concentrations when compared to preoperative values. Serum haptoglobin concentrations began to rise by the 6 h postoperative sample and were generally elevated above preoperative values by the 24 h postoperative sample. Two of the ten ponies had mild signs of postoperative colic which were associated with twofold elevations in serum haptoglobin concentrations and fivefold elevations in peritoneal fluid haptoglobin concentrations. 相似文献
109.
110.
Jamie S. Harmon Kim G. Michelsen Dr. Mark A. Sheridan 《Fish physiology and biochemistry》1991,9(4):361-368
Trialcylglycerol (TG) lipase was isolated and partially purified from rainbow trout liver. Triacylglycerol lipase activity was assayed by measuring14C-oleic acid release from14C-triolein.14C-oleic acid release was linear for up to two hours. Optimal activity occurred at pH 7.0 and 15°C. Most of the lipase activity was recovered in the cytosolic fraction. A 27,000-fold purification was achieved after Sepharose (Bio-gel A 0.5 M, 200–400 mesh) chromatography of a resuspended 20% ammonium sulfate fraction. The molecular weight of the trout hepatic lipase as determined by size-exclusion chromatography and by SDS-polyacrylamide gel electrophoresis was 40–43 kD. Lipase-mediated hydrolysis of TG resulted in the production of diacylglycerols, monoacylglycerols, and fatty acids. Kinetic analysis indicated that Vmax=0.016 nmol/h/mg protein and that Km=0.28 mM triolein. Lipolytic activity was enhanced in the presence of cAMP/ATP-Mg2+. These results suggest that the liver of trout possesses a neutral TG lipase that is responsible for mobilizing stored TG and is catalytically activated by phosphorylation.A part of this work was presented at the Annual Meeting of the American Society of Zoologists, December 26–30, 1990, San Antonio, TX. 相似文献