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41.
A 5-day-old Angus x Hereford calf presented for bilateral haired masses on the eyes and nasolabial planum since birth. The masses were surgically excised from the inferonasal cornea and bulbar conjunctiva of both eyes and the left and right side of the dorsomedial nasolabial planum. Histopathology of the excised tissue confirmed bilateral corneoconjunctival dermoids with ectopic lacrimal glands, and bilateral nasal choristomas and ectopic nasal glandular tissue. Surgery was curative and healing was uneventful. Bilateral ocular dermoids in combination with nasal choristomas and ectopic glandular tissue have not been documented previously in cattle. 相似文献
42.
Heat dissipation sensors of variable length for the measurement of sap flow in trees with deep sapwood 总被引:1,自引:0,他引:1
Robust thermal dissipation sensors of variable length (3 to 30 cm) were developed to overcome limitations to the measurement of radial profiles of sap flow in large-diameter tropical trees with deep sapwood. The effective measuring length of the custom-made sensors was reduced to 1 cm at the tip of a thermally nonconducting shaft, thereby minimizing the influence of nonuniform sap flux density profiles across the sapwood. Sap flow was measured at different depths and circumferential positions in the trunks of four trees at the Parque Natural Metropolitano canopy crane site, Panama City, Republic of Panama. Sap flow was detected to a depth of 24 cm in the trunks of a 1-m-diameter Anacardium excelsum (Bertero & Balb. ex Kunth) Skeels tree and a 0.65-m-diameter Ficus insipida Willd. tree, and to depths of 7 cm in a 0.34-m-diameter Cordia alliodora (Ruiz & Pav.) Cham. trunk, and 17 cm in a 0.47-m-diameter Schefflera morototoni (Aubl.) Maguire, Steyerm. & Frodin trunk. Sap flux density was maximal in the outermost 4 cm of sapwood and declined with increasing sapwood depth. Considerable variation in sap flux density profiles was observed both within and among the trees. In S. morototoni, radial variation in sap flux density was associated with radial variation in wood properties, particularly vessel lumen area and distribution. High variability in radial and circumferential sap flux density resulted in large errors when measurements of sap flow at a single depth, or a single radial profile, were used to estimate whole-plant water use. Diurnal water use ranged from 750 kg H2O day-1 for A. excelsum to 37 kg H2O day-1 for C. alliodora. 相似文献
43.
Leucine-tRNA initiates at CUG start codons for protein synthesis and presentation by MHC class I 总被引:1,自引:0,他引:1
Starck SR Jiang V Pavon-Eternod M Prasad S McCarthy B Pan T Shastri N 《Science (New York, N.Y.)》2012,336(6089):1719-1723
Effective immune surveillance by cytotoxic T cells requires newly synthesized polypeptides for presentation by major histocompatibility complex (MHC) class I molecules. These polypeptides are produced not only from conventional AUG-initiated, but also from cryptic non-AUG-initiated, reading frames by distinct translational mechanisms. Biochemical analysis of ribosomal initiation complexes at CUG versus AUG initiation codons revealed that cells use an elongator leucine-bound transfer RNA (Leu-tRNA) to initiate translation at cryptic CUG start codons. CUG/Leu-tRNA initiation was independent of the canonical initiator tRNA (AUG/Met-tRNA(i)(Met)) pathway but required expression of eukaryotic initiation factor 2A. Thus, a tRNA-based translation initiation mechanism allows non-AUG-initiated protein synthesis and supplies peptides for presentation by MHC class I molecules. 相似文献
44.
Streptococcus equi is the etiologic agent of a highly infectious upper respiratory disease of horses known as strangles. Bacterial culture methods and polymerase chain reaction (PCR) of nasopharyngeal washes and guttural pouch lavages are used routinely to test clinical and carrier animals for the presence of S. equi but no definitive or gold standard test method has been shown to be optimal. We hypothesized that (i) a flocked swab submerged in ten-fold serial dilution suspensions of S. equi prepared in 0.9% NaCl would detect more colony forming units (CFU) than a rayon swab when used to inoculate a blood agar plate, (ii) centrifugation of a 1ml aliquot of each suspension would improve the limit of detection (LOD) by bacterial culture and PCR compared to the culture or PCR of submerged swab samples, (iii) PCR of the centrifuged samples from each suspension would be more sensitive than aerobic culture alone, and (iv) PCR of a 1ml aliquot directly from a sample would be more sensitive than PCR of a sample following submersion of a flocked swab in 1ml saline. Using 7 ten-fold serial dilutions of S. equi in 0.9% NaCl, the LOD for 4 bacterial culture methods and 3 PCR methods were compared. The LOD of direct PCR and flocked swab culture was determined at 1cfu/ml. All PCR methods were equivalent to each other and were more sensitive than any of the culture methods at the lower dilutions. At higher cell densities (>100cfu/ml) flocked swab culture was not statistically better than rayon swab culture, but it was superior to all other methods tested. 相似文献
45.
46.
Horney BS MacKenzie AL Burton SA Olexson DW Mitton KL Coty WA Rinne SG 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》1999,28(1):20-28
A homogenous enzyme immunoassay (EIA) for measurement of serum thyroxine (T4) concentration was evaluated for use with canine and feline serum. The EIA method was linear from 0 to 150 nmol T4/L for human serum, 0 to 94 nmol T4/L for feline serum and 10 to 60 nmol T4/L for canine serum. Intra- and interassay precision studies yielded coefficients of variation = 8% using single point measurements. Method comparison studies gave close agreement between radioimmunoassay (RIA) and EIA results. Correlation coefficients (r values) were 0.88 and 0.97 for canine and feline samples respectively, after application of species-specific factors to correct the calibrator values assigned for human serum samples. The EIA showed no interference from hemolysis at hemoglobin concentrations = 20 g/L or from moderate lipemia. Highly lipemic specimens could be tested after centrifugation to clarify the sample. The EIA showed less interference from autoantibodies to T4 than the RIA method. The EIA method allows automation of T4 testing in a veterinary hospital or laboratory, and can be integrated with the routine clinical chemistry panel. 相似文献
47.
Newman SJ Langston CE Scase TJ 《Journal of the American Veterinary Medical Association》2003,222(2):180-3, 174
A 5-year-old castrated male Golden Retriever was evaluated for polyuria, polydipsia, and progressive regurgitation thought to be a result of bacterial pyelonephritis and megaesophagus. Bacteriologic culture of urine failed to yield clinically relevant growth, and results of a urine sediment examination were normal. With time, intention tremors and progressive neurologic dysfunction were also observed. At necropsy, a diagnosis of cryptococcal disease was confirmed histologically and immunohistochemically. Findings in the dog of this report were indicative of nephrogenic diabetes insipidus with polyuria and polydipsia caused by cryptococcal pyelonephritis. Neurologic manifestations of systemic cryptococcus infection included megaesophagus, esophageal hypomotility, and regurgitation attributed to localization of cryptococcal organisms in the brain stem in the region of the dorsal motor nucleus of the vagus nerve. To the authors' knowledge, this is the first report of polyuria secondary to cryptococcal pyelonephritis. 相似文献
48.
Bert A Shelley 《Veterinary Clinics of North America: Small Animal Practice》2002,32(3):621-37, vii
The skin of the perianal region is very thin and sensitive. The carbon dioxide laser is a very effective tool for removing tumors and treating conditions of this area. It offers a "no touch" method of treatment for conditions of the perianal region. There is less bleeding, less pain, less swelling with the use of the carbon dioxide laser. The carbon dioxide laser is an effective tool for excising perianal tumors, rectal tumors, performing anal sacculectomies and treating perianal fistulas. 相似文献
49.
Horney BS Farmer AJ Honor DJ MacKenzie A Burton S 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》1994,23(3):98-102
Cats with hyperthyroidism [(increased serum thyroxine (T(4))] commonly have increased serum alkaline phosphatase (ALP) activity in addition to other serum biochemical abnormalities. Serum biochemical profiles were obtained from 10 hyperthyroid cats which had increased serum ALP. Agarose gel electrophoresis of serum from these cats was performed and stained for alkaline phosphatase activity. Alkaline phosphatase activity was calculated for each of the separate bands obtained, and the results were compared to those of tissue extracts, serum from normal cats, and serum from normothyroid cats with increased serum ALP activity. The hyperthyroid cats had increased ALP activity in bands corresponding to isoenzymes originating in the liver, bone, and an unidentified tissue source. 相似文献
50.
Horney BS Honor DJ MacKenzie A Burton S 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》1993,22(1):5-9
Serum sorbitol dehydrogenase (SDH) activities in 10 cows and nine horses were measured using an automated clinical analyzer. The serum samples were divided into aliquots that were stored at room temperature (21 degrees C), refrigerated (0-5 degrees C), or frozen (-30 degrees C). The stability of the SDH activity was monitored at various intervals. SDH activity in bovine sera remained stable for at least 5 hours at room temperature, 24 hours refrigerated, and 72 hours frozen without any significant (p < 0.05) differences from the initial serum values. In equine sera, SDH activity remained stable for at least 5 hours at room temperature and 48 hours frozen. The activity of the refrigerated equine sera was stable for at least 5 hours but less than 24 hours. An evaluation of fresh bovine serum and heparinized plasma samples indicated that there was no significant difference (p < 0.05) between the two sampling methods and that either may be employed for automated measurement of SDH activity following the established protocol. Sample type comparison indicated that there was a small but statistically significant (p < 0.05) difference between the results obtained comparing fresh serum and heparinized plasma samples for the horse. A reference range for Holstein cows was established using sera from 71 clinically healthy cattle (mean -/+ 2 SD = 32 -/+ 26 U/L). 相似文献