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排序方式: 共有1311条查询结果,搜索用时 31 毫秒
991.
Benjamin W. Brunson J. Brad Case Gary W. Ellison W. Alexander Fox-Alvarez Stanley E. Kim Matthew Winter Fernando L. Garcia-Pereira Lisa L. Farina 《The Canadian veterinary journal. La revue veterinaire canadienne》2016,57(1):59-64
This study evaluated the safety of preoperative computed tomography angiography (CTA) and its effect on surgical time and clinical outcomes in dogs that underwent surgical correction of a single congenital extrahepatic portosystemic shunt (CEPSS). Patient data were retrospectively collected from medical records and owner communications for 124 dogs with single CEPSS, undergoing preoperative CTA (n = 43) or not (n = 81) which were surgically treated from 2005 to 2014. The frequency of major postoperative complications was 4.7% and 9.9% for the CTA and no CTA groups, respectively (P = 0.49). Mean ± standard deviation (SD) surgical time for the preoperative CTA group was 84 ± 40 min and 81 ± 31 min for the no CTA group (P = 0.28). We conclude that anesthetized preoperative CTA appears to be a safe method for diagnosis and surgical planning in dogs with single CEPSS, and does not appear to affect surgical procedure time, complication rate, or clinical outcome. 相似文献
992.
Rob L Coke Michael M Garner Gary D West John P Hoover Brian Murphy 《Journal of zoo and wildlife medicine》2006,37(3):401-404
A 16-yr-old, female, captive-bred bontebok (Damaliscus pygargus) estimated to be 75 kg, was presented with a 1-mo history of chronic diarrhea and weight loss. A cause for the deteriorating condition was not found antemortem, and the bontebok was humanely euthanatized when it failed to respond to empirical therapy. On necropsy, numerous nodules were present on the pleural surfaces and within the lung parenchyma, the pancreas appeared inflamed and fibrotic. Histologic examination revealed lymphoma in the mesenteric lymph nodes, alimentary tract, reproductive tract, and liver. In the small and large intestine, rumen, esophagus, bile duct, and vagina, the neoplastic cells had a tropism for epithelium. The neoplastic cells within the epithelium and subepithelium of the alimentary tract stained positively for CD3, consistent with T cell differentiation. 相似文献
993.
Garry O Kelley Francisco J Zagmutt-Vergara Christian M Leutenegger Karin A Myklebust Mark A Adkison Terry S McDowell Gary D Marty Alex L Kahler Arla L Bush Ian A Gardner Ronald P Hedrick 《Journal of veterinary diagnostic investigation》2004,16(3):202-211
Diagnostic methods were used to identify and quantify Myxobolus cerebralis, a myxozoan parasite of salmonid fish. In this study, 7-week-old, pathogen-free rainbow trout (Oncorhynchus mykiss) were experimentally infected with M. cerebralis and at 7 months postinfection were evaluated with 5 diagnostic assays: 1) pepsin-trypsin digest (PTD) to detect and enumerate spores found in cranial cartilage, 2) 2 different histopathology grading scales that provide a numerical score for severity of microscopic lesions in the head, 3) a conventional single-round polymerase chain reaction (PCR), 4) a nested PCR assay, and 5) a newly developed quantitative real-time TaqMan PCR. There were no significant differences (P > 0.05) among the 5 diagnostic assays in distinguishing between experimentally infected and uninfected control fish. The 2 histopathology grading scales were highly correlated (P < 0.001) for assessment of microscopic lesion severity. Quantification of parasite levels in cranial tissues using PTD and real-time TaqMan PCR was significantly correlated r = 0.540 (P < 0.001). Lastly, 104 copies of the 18S rDNA gene are present in the M. cerebralis genome, a feature that makes this gene an excellent target for PCR-based diagnostic assays. Also, 2 copies of the insulin growth factor-I gene are found in the rainbow trout genome, whose detection can serve both as an internal quality control for amplifiable DNA and as a basis to quantify pathogen genome equivalents present in quantitative PCR assays. 相似文献
994.
Objectives— To compare in vitro monotonic biomechanical properties of an equine spoon plate (ESP) with an axial 3‐hole, 4.5 mm narrow dynamic compression plate (DCP) using 5.5 mm cortical screws in conjunction with 2 abaxial transarticular 5.5 mm cortical screws (DCP‐TLS) inserted in lag fashion for equine proximal interphalangeal (PIP) joint arthrodesis. Study Design— Paired in vitro biomechanical testing of 2 methods of stabilizing cadaveric adult equine forelimb PIP joints. Animal Population— Cadaveric adult equine forelimbs (n=18 pairs). Methods— For each forelimb pair, 1 PIP joint was stabilized with an ESP (8 hole, 4.5 mm) and 1 with an axial 3‐hole narrow DCP (4.5 mm) using 5.5 mm cortical screws in conjunction with 2 abaxial transarticular 5.5 mm cortical screws inserted in lag fashion. Six matching pairs of constructs were tested in single cycle to failure under axial compression with load applied under displacement control at a constant rate of 5 cm/s. Six construct pairs were tested for cyclic fatigue under axial compression with cyclic load (0–7.5 kN) applied at 6 Hz; cycles to failure were recorded. Six construct pairs were tested in single cycle to failure under torsional loading applied at a constant displacement rate (0.17 radians/s) until rotation of 0.87 radians occurred. Mean values for each fixation method were compared using a paired t‐test within each group with statistical significance set at P<.05. Results— Mean yield load, yield stiffness, and failure load for ESP fixation were significantly greater (for axial compression and torsion) than for DCP‐TLS fixation. Mean (± SD) values for the ESP and DCP‐TLS fixation techniques, respectively, in single cycle to failure under axial compression were: yield load 123.9 ± 8.96 and 28.5 ± 3.32 kN; stiffness, 13.11 ± 0.242 and 2.60 ± 0.17 kN/cm; and failure load, 144.4 ± 13.6 and 31.4 ± 3.8 kN. In single cycle to failure under torsion, mean (± SD) values for ESP and DCP‐TLS, respectively, were: stiffness 2,022 ± 26.2 and 107.9 ± 11.1 N m/rad; and failure load: 256.4 ± 39.2 and 87.1 ± 11.5 N m. Mean cycles to failure in axial compression of ESP fixation (622,529 ± 65,468) was significantly greater than DCP‐TLS (95,418 ± 11,037). Conclusion— ESP was superior to an axial 3‐hole narrow DCP with 2 abaxial transarticular screws inserted in lag fashion in resisting static overload forces and cyclic fatigue. Clinical Relevance— In vitro results support further evaluation of ESP for PIP joint arthrodesis in horses. Its specific design may provide increased stability without need for external coaptation support. 相似文献
995.
Feary DJ Magdesian KG Aleman MA Rhodes DM 《Journal of the American Veterinary Medical Association》2007,231(2):259-266
OBJECTIVE: To investigate the clinical, clinicopathologic, and diagnostic characteristics; treatment; and outcome associated with acute traumatic brain injury (TBI) in horses and assess risk factors for nonsurvival in TBI-affected horses. DESIGN: Retrospective case series. ANIMALS: 34 horses with TBI. Procedures-Medical records of horses that had sustained trauma to the head and developed neurologic signs were reviewed. Data that included signalment, clinicopathologic findings, diagnosis, treatment, and outcome were analyzed. Clinicopathologic variables among horses in survivor and nonsurvivor groups were compared, and risk factors for nonsurvival were determined. RESULTS: Median age of affected horses was 12 months. Findings of conventional survey radiography of the head alone failed to identify all horses with fractures of the calvarium. Horses with basilar bone fractures were 7.5 times as likely not to survive as horses without this type of fracture. Depending on clinical signs, horses received supportive care, osmotic or diuretic treatments, antimicrobials, anti-inflammatory drugs, analgesics, or anticonvulsants. Twenty-one (62%) horses survived to discharge from the hospital. In the nonsurvivor group, mean PCV was significantly higher, compared with the value in the survivor group (40% vs 33%). Risk factors associated with nonsurvival included recumbency of more than 4 hours' duration after initial evaluation (odds ratio, 18) and fracture of the basilar bone (odds ratio, 7.5). CONCLUSIONS AND CLINICAL RELEVANCE: Results suggest that prognosis for survival in horses with acute TBI may be more favorable than previously reported. Among horses with TBI, persistent recumbency and fractures involving the basilar bones were associated with a poor prognosis. 相似文献
996.
Griebel PJ Entrican G Rocchi M Beskorwayne T Davis WC 《Veterinary immunology and immunopathology》2007,119(1-2):115-122
A panel of 377 commercially available mAbs was submitted to the animal homologue section of the Eighth International Workshop on Human Leukocyte Differentiation Antigens (HLDA8, Adelaide, Australia) for cross-reactivity studies in a range of vertebrate species. Eight commercial suppliers participated by providing isotype controls and mAbs specific for a total of 144 CD antigens. In this study, we describe the results of flow cytometric testing of the reactivity of these mAbs with leukocyte populations isolated from blood, bronchoalveolar lavage, and ileal Peyer's patches of sheep. A total of 52 mAbs were identified as potentially reacting with sheep blood leukocytes in the first round of screening with blood leukocytes. In the second phase, reactivity of selected mAbs was further analyzed by repeating the screening with blood leukocytes at an independent facility. Screening of selected mAbs for reactivity with myeloid antigens was completed with alveolar macrophages and screening for reactivity with B cell antigens was completed with ileal Peyer's patch B cells. This screening identified mAbs that consistently reacted with both putative myeloid (CD10, CD22, CD23, CD27, CD29, CD32, CD49d, CD81, CD86, CD88, CD163, CD165) and B cell (CD10, CD22, CD23, CD27, CD29, CD32, CD49d, CD81, CD86, CD88, CD165) activation or differentiation antigens. Further studies will be required to determine if each mAb cross-reacts with an orthologous leukocyte antigen. 相似文献
997.
Zieba DA Klocek B Williams GL Romanowicz K Boliglowa L Wozniak M 《Domestic animal endocrinology》2007,33(3):358-365
Recent observations in seasonal-breeding mammals indicate that the hypothalamus is programmed to become leptin resistant during long days (LD) and leptin sensitive during short days (SD). These observations support the possibility that photoperiod mediates at least part of its effects on melatonin secretion through changes in leptin sensitivity. Herein we examined the interaction of season and recombinant ovine leptin (oleptin) on melatonin secretion by pineal explants in short-term culture. Glands were collected after sunset from eight ewes during LD (March, April, May, June) and from an additional eight ewes during SD (September, October, November, December). Glands were transected saggitally and coronally into quarters, with each equilibrated in 2.5ml of DMEM for 120min, followed by a 3h incubation in medium containing either 0 or 50ng/ml of oleptin. Treatment with oleptin reduced (P<0.001) melatonin secretion compared to controls during LD by approximately 22% at 2, 2.5 and 3h of culture. However, in cultures from glands collected during SD, oleptin stimulated (P<0.078) melatonin secretion approximately 50% compared to control. These effects were consistent throughout each respective season. We conclude that the secretion of melatonin from the ovine pineal gland is negatively responsive to leptin during LD, whereas leptin may stimulate melatonin secretion during SD. 相似文献
998.
Flavonoid content and radical scavenging activity in fruits of Chinese dwarf cherry(Cerasus humilis) genotypes 总被引:1,自引:0,他引:1
Pengfei Wang Xiaopeng Mu Junjie Du Yu Gary Gao Donghai Bai Luting Jia Jiancheng Zhang Haiyan Ren Xiaofang Xue 《林业研究》2018,(1)
The Chinese dwarf cherry(Cerasus humilis(Bge.) Sok.) is a small shrub with edible fruits. It is native to northern and western China. This species was included as a medicinal plant in the ‘‘Chinese Pharmacopeia' and has emerged as an economically important crop for fresh fruit consumption, processing into juice and wine and nutraceutical products as well. To gain a better understanding of flavonoid biosynthesis and help develop value added products and better cultivars with greater health benefits, we analyzed total flavonoid content(TFC), composition, and radical scavenging activities in fruit extracts of 16 Chinese dwarf cherry genotypes. Fruit peel TFC ranged from 33.5 to72.8 mg/g REáFW(RE: rutin equivalent, FW: fresh weight)while fruit flesh TFC ranged from 4.3 to 16.9 mg/g REáFW.An HPLC analysis revealed that fruit extracts contained 14 flavonoids with considerable variation in their profiles across genotypes. The most abundant flavonoids in most genotypes were proanthocyanidin B1(PA-B1), proanthocyanidin B2(PA-B2), phloretin 20-O-glucoside(PG), and phloretin 20,40-O-diglucoside(PDG). Principal component analysis showed that PG, PA-B1, and PA-B2 had large,positive factor loading values in the first principal component for each genotype. Increased scavenging activity of2,2-diphenyl-1-picrylhydrazyl(DPPH) radicals was apparent in genotypes ‘Nongda 4', ‘Nongda 3', ‘Nongda 6',‘Wenfenli', and '10-32', suggesting promising applications in the production of nutraceutical products. In summary, our results will aid in breeding, fruit processing, and developing medicinal uses of the Chinese dwarf cherry. 相似文献
999.
Ying Ouyang Gary Feng Prem Parajuli Theodor Leininger Yongshan Wan Johnie N. Jenkins 《Water, air, and soil pollution》2018,229(11):373
Assessment of surface water quality in the Mississippi Delta is essential to quantify the eutrophication of the Gulf of Mexico. This study estimated the characteristics and variations of surface water quality at three study sites in the Big Sunflower River Watershed (BSRW) within the Mississippi Delta using Kruskal-Wallis, Dunn, Mann-Kendall, and Pettitt tests. In general, contents of some water quality constituents such as nitrate-nitrogen (NO3???N) and total phosphorus (TP) in the BSRW varied from site to site each year, whereas variations of other constituents such as pH and dissolved oxygen (DO) each year were basically not significant. The highest median concentrations were found in spring for NO3???N and total nitrogen (TN); in summer for specific conductance (SC), Na, and Cl; and in winter for DO. Mann-Kendall trend analysis revealed that there was an increasing annual trend at Leland but a decreasing annual trend at Merigold for NO3???N concentrations even though such changes were very small, whereas there was no annual trend for TP at any of the three study sites. Pettitt’s test further identified that the NO3???N concentrations had an abrupt increase in February 2009 at the median value of 0.44 mg L?1 in Leland and an abrupt decrease in June 2012 at the median value of 3.65 mg L?1 in Merigold. A very good linear correlation existed between total dissolved solid (TDS) and magnesium (Mg) in the BSRW, which could be used to estimate TDS from Mg concentrations for this watershed when the data for TDS are absent. 相似文献
1000.