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31.
32.
Pituitary adenomas are commonly reported in older horses. The typical clinical signs associated with this condition, also known as equine Cushing's disease (ECD), are related to increased adrenocorticotropin (ACTH) production resulting in hyperadrenocorticism. The primary purpose of this study was to determine whether plasma ACTH concentrations differed between cushingoid and healthy horses. The second objective was to determine the effects of blood sample handling techniques on ACTH concentrations. A commercial human ACTH radioimmunoassay (RIA) was used to quantify equine plasma ACTH. Intra-assay and interassay variations, as well as dilutional parallelism were determined during the RIA validation. Plasma ACTH concentrations were evaluated in a group of healthy equids composed of 18 horses and 9 ponies, and in 22 equids with a clinical diagnosis of hyper adrenocorticism (11 horses and 11 ponies). The mean plasma ACTH concentrations in healthy horses and ponies, (18.68 ± 6.79 pg/mL (mean ± SD) and 8.35 ± 2.92 pg/mL, respectively), were significantly different (P = .009). The mean plasma ACTH concentration in horses and ponies with ECD, (199.18 ± 182.82 pglmL and 206.21 ± 319.56 pg/mL, respectively), were significantly higher than the mean ACTH concentration in the control animals (P < .001). Plasma ACTH concentrations appeared to be a sensitive and specific indicator of ECD in horses and ponies. ACTH concentrations measured in plasma samples kept at room temperature (19°C) as long as 3 hours after blood collection were not statistically different from those of samples kept at 1°C. J Vet Intern Med 1996;10:1–6. Copyright 1996 by the American College of Veterinary Internal Medicine .  相似文献   
33.
A monoclonal gammopathy composed of immunoglobulin G, with concurrent light-chain proteinuria and generalized lymph node plasmacytosis, was associated with chronic pyoderma in a dog. A uniform population of plasma cells was observed cytologically and histologically in multiple lymph node specimens. A diagnosis of monoclonal gammopathy of unknown significance was eventually made by exclusion of other known causes of monoclonal gammopathy, resolution after antibiotic therapy, and no evidence of lymphoproliferative disease after 11 months of follow-up and subsequent necropsy. This report expands the diagnostic considerations for monoclonal gammopathies in the dog.  相似文献   
34.
Oxidative damage plays an important role in the pathophysiology of diabetes and diabetic complications. Feline hemoglobin is uniquely susceptible to oxidative denaturation; therefore, Heinz body formation is a highly sensitive indicator of in vivo oxidative stress in this species. Heinz bodies also contribute to anemia. We investigated hematological and clinical biochemical changes in 30 cats with spontaneous diabetes mellitus (as compared to 15 healthy control cats) and evaluated the relationship of these changes to erythrocyte oxidative damage. Cats were categorized as ketoacidotic or nonketoacidotic based on their clinical presentation and the presence of urine ketones. Ketoacidotic cats had significantly ( P = .0009) more Heinz bodies (28.3% ± 9.1 %) than nonketotic diabetic cats (6.5% ± 1.60%) and healthy control cats (0.6% ± 0.2%). Percent Heinz bodies in diabetic cats directly correlated with plasma β-hydroxy-butyrate concentration ( r = .622; P = .0002), as well as with serum chloride concentration ( r = -0.576; P = 0.0009) and the number of monocytes ( r = .536; P = .0023). Percent Heinz bodies were negatively correlated with erythrocyte glutathione concentrations. Erythrocyte membrane lipid peroxidation was slightly but not significantly increased in diabetic cats. There were no significant associations between percent Heinz bodies and degree of anemia, hyperglycemia, or glycohemoglobin. These data indicate that ketones are associated with oxidative hemoglobin damage in cats, and suggest that ketone metabolism, ie by cytochrome P450 2E1, may be a potential source of in vivo oxygen radical generation in animals with ketosis.  相似文献   
35.
Two hand rasps (tungsten chip blade, solid carbide blade) and an electrically-driven solid carbide axial bur were used to treat the cheek teeth of 2 horses immediately postmortem. All teeth were normal and were rasped to a standard considered satisfactory in practice. Six teeth from each horse served as untreated controls. Following treatment, the teeth were extracted and the clinical crown removed and prepared for scanning electron microscopy. Teeth were also extracted and examined from a horse that had excessive dental treatment previously. Dental debris created by the procedures was collected and examined. All three rasp techniques resulted in amputation of odontoblast processes. The solid carbide blade cut deep gouges and grooves into the surface of the dentin, chipping the enamel and peripheral cement. No smear layer was created. Rasping with a tungsten chip blade created a partial smear layer and a smoother surface than the solid carbide blade. The electrically-driven bur produced a complete smear layer and removed all dental tissues to a smooth layer. The enamel had also been damaged by the electric bur. Crown particles collected after the procedures were larger following hand rasping compared with particles produced by the electric bur. The extent of damage to sensitive and vital dentin tissue was of concern. Further studies are required to establish the optimum technique for rasping equine cheek teeth.  相似文献   
36.
Keller M  Viret O  Cole FM 《Phytopathology》2003,93(3):316-322
ABSTRACT Inflorescences of field-grown grapevines (Vitis vinifera L. cv. Gamay) were inoculated with a Botrytis cinerea conidia suspension or dried conidia at different stages during bloom in moist weather. Approximately 10% of the conidia germinated within 72 h, resulting in two to three times more latent infections than uninoculated controls in pea-size (7 mm in diameter) berries. In surface-sterilized pea-size berries, latent B. cinerea was present predominantly in the receptacle area. After veraison, latent B. cinerea also was found in the style and, in mature berries, latent colonies were distributed throughout the pulp. Inoculation at full bloom led to the highest disease severity (66%) at harvest, compared with 38% in controls. Stilbene stress metabolites in the flowers were measured by high-performance liquid chromatography. Resveratrol accumulated mainly after pre-bloom and full-bloom inoculation, but did not prevent infection. Piceid levels did not change following inoculation, while epsilon-viniferin was found in necrotic tissues only, and pterostilbene and alphaviniferin were not detected at all. B. cinerea conidia suspensions also were applied to various locations on flowers of pot-grown cvs. Pinot Noir and Chardonnay. Inoculation of the receptacle area, but not that of the stigma and ovary, resulted in latent infections. Stilbene synthesis was similar to the field results, with resveratrol accumulating mainly in the calyptra and receptacle area. Constitutive soluble phenolic compounds (mainly derivatives of quercetin and hydroxy-cinnamic acid) were present at high concentrations in the calyptra but at low levels in the receptacle area. These experiments confirmed bloom as a critical time for B. cinerea infection in grapes and suggest that the most likely site of infection is the receptacle area or cap scar exposed at anthesis. Stilbenes may have a limited role in inhibition of flower infection and latency in susceptible grape cultivars, and epsilon-viniferin may be a by-product rather than a deterrent of infection.  相似文献   
37.
OBJECTIVE: To describe the demographic and clinical characteristics of a population of geriatric horses. DESIGN: Retrospective study. ANIMALS: 467 horses that were > or = 20 years of age. PROCEDURE: Medical records of 539 geriatric horses that were evaluated at a university large animal hospital between 1989 and 1999 were reviewed. Data collected included signalment, reason for evaluation, specific diagnoses, surgical procedures, inpatient or outpatient care, duration of hospitalization, and outcome. RESULTS: 467 horses met the criteria for inclusion in the study. Horses that were > or = 20 years of age comprised 2.2 and 12.5% of horses evaluated during 1989 and 1999, respectively. Pony breeds were significantly overrepresented in the > or = 30-years-of-age group. Gastrointestinal tract, musculoskeletal, and respiratory tract problems were most frequently reported. Colic was the most common clinical sign, followed by lameness. Diagnoses made most frequently included pituitary dysfunction, strangulating lipoma of the small intestine, laminitis, heaves, large colon impaction, and gastric ulcers. Pituitary dysfunction was significantly more prevalent in horses that were > 30 years of age. Laminitis was significantly associated with the presence of pituitary dysfunction. CONCLUSIONS AND CLINICAL RELEVANCE: It was difficult to assess association of age with illnesses identified in these horses. Demographic data and information regarding common diseases of horses that are > or = 20 years of age are limited but will become increasingly important as this geriatric population increases.  相似文献   
38.
OBJECTIVE: To describe the demographic and clinical characteristics, management practices, and owner perception of a population of geriatric horses, and to compare these data with findings in a group of younger horses. DESIGN: Original study. ANIMALS: 218 horses. PROCEDURE: Data were collected via a survey tool from owners of 165 horses that were > or = 20 years of age and 53 horses that were < 20 years of age. RESULTS: Compared with young horses, the geriatric group included a significantly greater number of ponies; geriatric horses were also more likely to have a history of colic, dental disease, tumors, lameness, and pituitary disease, but not laminitis, diarrhea, allergies, respiratory tract disease, thyroid disease, or fractures. Horses that had participated in Western equestrian disciplines were more likely to have a history of lameness. Among old horses, those with pituitary dysfunction were more likely to have a history of laminitis than those without pituitary dysfunction. Geriatric horses were more likely to have long hair and shedding abnormalities than were younger horses. Owners perceived their horses as old at approximately 22 years of age. In horses older than 16.5 years of age, age was a negative factor in the purchase of horses. CONCLUSIONS AND CLINICAL RELEVANCE: Geriatric and young horses share some similar health problems, but old horses have distinct health problems and veterinary medical requirements. The management and athletic history of horses may influence health as they age.  相似文献   
39.
OBJECTIVE: To characterize the signalment, clinical signs, biological behavior, and response to treatment of carcinoma of the apocrine glands of the anal sac in dogs. DESIGN: Retrospective study. ANIMALS: 113 dogs with histologically confirmed carcinoma of the apocrine glands of the anal sac. PROCEDURE: Data on signalment, clinical signs, and staging were reviewed and analyzed along with treatment modality for potential association with survival time. RESULTS: Sex distribution was approximately equal (54% female, 46% male). One hundred four dogs underwent treatment consisting of surgery, radiation therapy, chemotherapy, or multimodal treatment. Median survival for treated dogs was 544 days (range, 0 to 1,873 days). Dogs treated with chemotherapy alone had significantly shorter survival (median, 212 days) than those receiving other treatments (median, 584 days). Dogs not treated with surgery had significantly shorter survival (median, 402 days) than those that underwent surgery as part of their treatment (median, 548 days). Dogs with tumors > or = 10 cm2 had significantly shorter survival (median, 292 days) than dogs with tumors < 10 cm2 (median, 584 days). Hypercalcemia was identified in 27% (n = 29) of dogs, and those dogs had significantly shorter survival (median, 256 days), compared with those that were normocalcemic (median, 584 days). Dogs with pulmonary metastasis had significantly shorter survival (median, 219 days) than dogs without evidence of pulmonary metastasis (median, 548 days). CONCLUSIONS AND CLINICAL RELEVANCE: Unlike most previous reports, this study revealed an approximately equal sex distribution, and results suggest a more favorable prognosis.  相似文献   
40.
OBJECTIVE: To examine in vitro effects of various antiproteolytic compounds on activity of matrix metalloproteinase (MMP)-2 and -9 in the tear film of horses with active corneal ulcers. SAMPLE POPULATION: Samples of tear film obtained from the eyes of 34 horses with active ulcerative keratitis. PROCEDURE: Horses were sedated, and tear samples were collected from the lower fornix of 34 ulcerated eyes by use of capillary tubes. The protease inhibitors 0.2% EDTA, 0.1% doxycycline, 10% N-acetylcysteine (NAC), 0.1% solution of a modified dipeptide that contains hydroxamic acid (ie, ilomostat), 0.1% alpha1-proteinase inhibitor (PI), 0.5% alpha1-PI, and 100% fresh equine serum (ES) were used to treat pooled samples. Amount of latent and active MMP-2 and -9 was measured by optical density scanning of gelatin zymograms of treated and untreated tear samples. RESULTS: Pooled tear samples obtained from ulcerated eyes contained the latent and active forms of MMP-2 and -9. Compared with MMP activity in untreated samples, total MMP activity (sum of all bands detected) observed on the gelatin zymogram gels was reduced by 99.4% by EDTA, 96.3% by doxycycline, 98.8% by NAC, 98.9% by ilomostat, 52.4% by 0.1% alpha1-PI, 93.6% by 0.5% alpha1-PI, and 90.0% by ES. CONCLUSIONS AND CLINICAL RELEVANCE: We documented that EDTA, doxycycline, NAC, ilomostat, alpha1PI, and ES inhibited MMP activity in vitro. Because these compounds use different mechanisms to inhibit various families of proteases in the tear film of horses, a combination of these protease inhibitors may be beneficial for treatment of corneal ulcers in horses.  相似文献   
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