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21.
Purpose The goal of our study was the evaluation of a practical method for the recording of flash electroretinograms (ERGs) in sedated, standing horses with the DTL? microfiber electrode. Methods The horses were sedated intravenously with detomidine hydrochloride (0.015 mg/kg). The pupil was dilated and the auriculopalpebral nerve was blocked. The ERGs were recorded with the active electrode on the cornea (DTL?), the reference electrode near the lateral canthus, and the ground electrode over the occipital bone. The light intensities of the white strobe light were 0.03 cd·s/m2 (scotopic) and 3 cd·s/m2 (scotopic and photopic). Photopic and scotopic single flash and flicker responses to Ganzfeld stimulation were recorded. During the 20‐min dark adaptation period the retina was stimulated every 5 min with the 0.03 cd·s/m2 single flash. Results The median b‐wave amplitudes and implicit times were 38 µV and 33 ms (photopic cone‐dominated response), 43 µV and 63 ms (5‐min dark adaptation), 72 µV and 89 ms (10 min), 147 µV and 103 ms (15 min), 188 µV and 109 ms (20 min, 0.03 cd·s/m2, rod response), and 186 µV and 77 ms (20 min, 3 cd·s/m2, maximal combined rod‐cone response). A steady increase in amplitude and implicit time was noted during dark adaptation. No oscillatory potentials could be isolated. Conclusions The use of detomidine hydrochloride sedation and the DTL? microfiber electrode allowed the recording of good quality ERGs. This protocol should permit the detection of functional problems in the retina without the risk involved with general anesthesia. 相似文献
22.
Horter DC Yoon KJ Zimmerman JJ 《Animal health research reviews / Conference of Research Workers in Animal Diseases》2003,4(2):143-155
The porcine tonsils are a group of lymphoepithelial tissues located at the common openings of the gastrointestinal and respiratory tracts. The tonsils participate in a variety of functions involving innate, cellular and humoral immunity at the local and systemic levels. Among these immunological functions is the continuous surveillance for the presence of foreign antigens at the openings of the gastrointestinal and respiratory tracts. Within the pig, the movement of lymphocytes, cytokines and chemotactic molecules from the tonsils to other lymphoid organs confers immunity to other portals of pathogen entry and facilitates an efficient and rapid systemic immune response. In spite of the immunological nature of the tonsils, some microorganisms have acquired adaptations that allow them to circumvent the tonsillar immune defenses and utilize the tonsils as a site of entry, replication and colonization. Several bacterial and viral pathogens persist asymptomatically within the tonsils, making identification of asymptomatic carrier animals difficult in disease control and/or pathogen elimination. This paper reviews the current information on the anatomy, immunology and pathobiology of porcine tonsils and discusses the tonsils as a site of pathogen entry, replication and colonization using Salmonella spp., classical swine fever virus and porcine reproductive and respiratory syndrome virus as examples. 相似文献
23.
24.
Evaluation of various compounds to inhibit activity of matrix metalloproteinases in the tear film of horses with ulcerative keratitis 总被引:1,自引:0,他引:1
Ollivier FJ Brooks DE Kallberg ME Komaromy AM Lassaline ME Andrew SE Gelatt KN Stevens GR Blalock TD van Setten GB Schultz GS 《American journal of veterinary research》2003,64(9):1081-1087
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
25.
Paull LC Scott-Moncrieff JC DeNicola DB Glickman N Refsal KR Glickman LT 《Journal of the American Animal Hospital Association》2003,39(2):193-202
A placebo-controlled experiment was performed to evaluate the effect of potassium bromide on the canine thyroid gland. Basal total thyroxine, free thyroxine, and basal thyrotropin serum concentrations were evaluated over a 6-month period in potassium bromide-treated and control dogs. A thyrotropin-releasing hormone stimulation test was also performed in all dogs at the beginning and conclusion of the study. Thyroid histopathology was compared between treated and control dogs at the end of the study. No difference was detected in any parameter between the two groups at the end of the study. A decline in thyroid hormone concentrations over the course of the study did occur in both groups of dogs. Potassium bromide does not appear to have a significant effect on canine thyroid function or morphology. 相似文献
26.
Lora-Michiels M Biller DS Olsen D Hoskinson JJ Kraft SL Jones JC 《Journal of the American Animal Hospital Association》2003,39(5):452-458
Diseases of the accessory lung lobe (AccLL) are often overlooked in dogs and cats, perhaps because of its recessed location. Diseases of this lobe also can mimic diseases of the diaphragm or structures comprising the caudal mediastinum. Normal anatomy of the AccLL and the diagnostic tools used today will be reviewed to help differentiate disease of adjacent organs. Four cases will also be described to illustrate disease presentation and radiographic findings affecting this lobe. 相似文献
27.
Toribio RE Kohn CW Chew DJ Capen CC Rosol TJ 《American journal of veterinary research》2002,63(2):194-197
OBJECTIVES: To clone and sequence the cDNA for feline preproparathyroid hormone (preproPTH) and to compare that sequence with other known parathyroid hormone (PTH) sequences. SAMPLE POPULATION: Parathyroid glands from 1 healthy cat. PROCEDURES: A cDNA library was constructed in lambda phage from feline parathyroid gland mRNA and screened with a radiolabeled canine PTH probe. Positive clones were sequenced, and nucleic acid and deduced amino acid sequences were analyzed and compared with known preproPTH and PTH sequences. RESULTS: Screening of approximately 2 X 10(5) recombinant plaques revealed 3 that hybridized with the canine PTH probe; 2 clones comprised the complete sequence for feline preproPTH. Feline preproPTH cDNA consisted of a 63-base pair (bp) 5'-untranslated region (UTR), a 348-bp coding region, and a 326-bp 3'-UTR. The coding region encoded a 115-amino acid peptide. Mature feline PTH consisted of 84 amino acids. Amino acid sequence analysis revealed that feline PTH was > 83% identical to canine, bovine, swine, equine, human, and macaque PTH and 69, 71, and 44% identical to mouse, rat, and chicken PTH, respectively. Within the region responsible for hormonal activity (amino acids 1 to 34), feline PTH was > 79% identical to other mammalian PTH sequences and 64% identical to the chicken sequence. CONCLUSIONS AND CLINICAL RELEVANCE: The amino acid sequence of PTH is conserved among mammalian species. Knowledge of the cDNA sequence for feline PTH may be useful to investigate disturbances of calcium metabolism and alterations in PTH expression in cats. 相似文献
28.
Effects of diet restriction on life span and age-related changes in dogs 总被引:11,自引:0,他引:11
Kealy RD Lawler DF Ballam JM Mantz SL Biery DN Greeley EH Lust G Segre M Smith GK Stowe HD 《Journal of the American Veterinary Medical Association》2002,220(9):1315-1320
OBJECTIVE: To evaluate the effects of 25% diet restriction on life span of dogs and on markers of aging. DESIGN: Paired feeding study. ANIMALS: 48 Labrador Retrievers. PROCEDURES: Dogs were paired, and 1 dog in each pair was fed 25% less food than its pair-mate from 8 weeks of age until death. Serum biochemical analyses were performed, body condition was scored, and body composition was measured annually until 12 years of age. Age at onset of chronic disease and median (age when 50% of the dogs were deceased) and maximum (age when 90% of the dogs were deceased) life spans were evaluated. RESULTS: Compared with control dogs, food-restricted dogs weighed less and had lower body fat content and lower serum triglycerides, triiodothyronine, insulin, and glucose concentrations. Median life span was significantly longer for dogs in which food was restricted. The onset of clinical signs of chronic disease generally was delayed for food-restricted dogs. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggest that 25% restriction in food intake increased median life span and delayed the onset of signs of chronic disease in these dogs. 相似文献
29.
Jewell DE Yu S Joshi DK 《Veterinary therapeutics : research in applied veterinary medicine》2002,3(3):235-243
Skin problems are common in small animal practice. Oxidative stress, or the imbalance between prooxidants and the body's antioxidant defense system, likely plays a role in the development of skin disease. According to this study, increasing amounts of vitamin E in foods for dogs and cats increases serum and cutaneous concentrations of vitamin E. Based on available scientific data, these increases in vitamin E concentration are likely to be beneficial. However, the relationship between increases in serum and skin vitamin E concentrations and the prevention, development, and treatment of skin disease remains to be elucidated by intervention studies. 相似文献
30.
Michels GM Knapp DW DeNicola DB Glickman N Bonney P 《Journal of the American Animal Hospital Association》2002,38(5):458-466
The purpose of this study was to determine if the presence of histopathologically tumor-free versus nontumor-free margins was prognostic for relapse or tumor-related death in dogs following surgical excision of single or multiple cutaneous mast cell tumors confined to the skin without evidence of metastasis to lymph nodes or other noncutaneous sites. Differences in tumor-related death or frequency of relapse between the two groups were not significant. Failure to achieve histopathological tumor-free margins frequently did not lead to local relapse. All tumor-related deaths occurred following local relapse. The lack of statistical support for an association between prognosis and histopathological tumor-free versus nontumor-free margins may be a result of small sample size. 相似文献