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101.
Ronan A. Mullins MVB DECVS Carlos Sanchez Villamil DVM Laura E. Selmic BVetMed MPH DACVS-SA DECVS Michael S. Tivers BVSc PhD DECVS J. Brad Case DVM MS DACVS Ameet Singh BSc DVM DVSc DACVS Kelley M. Thieman Mankin DVM MS DACVS Davina M. Anderson MA VetMB PhD DSAS DECVS Robert N. White BSc BVetMed DSAS DECVS SFHEA Kathryn M. Pratschke MVB MVM DECVS Hilde de Rooster DVM MVM PhD DECVS Anne Kummeling DVM PhD DECVS Donald A. Yool BVMS PhD DECVS SFHEA Melanie Olive DVM Jean-Philippe Billet Dr vét DECVS Ines Gordo DVM MS Herve Brissot DV DECVS Cameron Broome BVSc DVCS FANZCVS Barbara M. Kirby DVM MS DACVS DECVS 《Veterinary surgery : VS》2020,49(5):958-970
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Jose L. Carvajal J. Brad Case Federico Vilaplana Grosso Elizabeth Huynh Valentine Verpaalen Alexander Fox‐Alvarez Penny J. Regier 《Veterinary radiology & ultrasound》2020,61(3):312-321
The objectives of this retrospective, observational study were to characterize the anatomical features of the cisterna chyli (CC) in a cohort of dogs diagnosed with idiopathic chylothorax that underwent CT lymphangiography (CTLa), and to evaluate the feasibility of computer‐assisted design (CAD) software to quantify volumetric measurements of the CC. Twenty‐three client‐owned dogs with idiopathic chylothorax were included. Additionally, CTLa was performed in three canine cadavers to assess the ability of CAD software to accurately acquire volumetric measurements. Injection sites, attenuation values, anatomic location, dimensions, and aortic diameter to CC ratio (Ao:CC) were recorded. Video records of video‐assisted thoracic surgery (VATS) thoracic duct ligation (TDL) were reviewed in eight out of 23 dogs to compare operative and CTLa findings. The CC was dorsal and right‐sided in 18 out of 23 dogs, located between L1 and L4 in 21 dogs, and extended as far cranially as T11 in two dogs. The median measurements for length, height, and width were 150.0, 5.5, and 13.3 mm, respectively. Median total volume was 1.82 mL. Median volumes to the right and left of the aorta were 1.46 and 0.49 mL, respectively (P = .014). Median total CC volume to body weight ratio (CC:bw) was 0.07 mL/kg. The presence of an intrathoracic CC was observed intraoperatively in six out of eight cases that underwent VATS TDL. Findings supported the use of CTLa and CAD as feasible methods for characterizing the CC in dogs diagnosed with chylothorax. These methods may facilitate interventional planning involving the CC such as embolization. 相似文献
104.
A feed trial was conducted for 59 days with juvenile Cherax destructor, mean weight (se) 0.61 (0.01) g, reared communally and maintained on 16 isoenergetic diets containing crude protein levels of 15, 20, 25, and 30%. For each protein level the fish meal component was replaced by soybean meal to produce diets in which 0, 20, 40, or 60% of the protein originated from soybean meal. Mean percentage weight gain per day ranged from 2.98% (15% protein, 60% soybean meal diet), to 11.75% (30% protein, 40% soybean meal diet). When soybean meal was included at a level of 40–60%, growth rate was reduced relative to that achieved with control diets at 15% and 20% protein levels. In no case did a 20% substitution significantly affect growth over that achieved with controls. A two-way interaction occurred between dietary protein and the level of dietary soybean meal. Feeds of higher protein content appeared to permit higher soybean meal inclusion levels without significantly affecting growth. Increases of 5% protein produced a significant improvement in growth when soybean meal contributed from 40–60% of the total protein. This effect was less pronounced in the control diets and the 20% soybean meal series. The percentages of protein increased and lipid decreased in the carcass as the level of dietary protein increased. A similar effect occurred by increasing the soybean meal substitution level to 60%. An obvious trend in carcass moisture, energy, and ash did not occur. A protein requirement of 30% is apparent when fish meal and soybean meal are included in diets at levels of 20% and 24% respectively. A maximum weight of 14.13 g was recorded for an individual fed the 30% protein, 20% soybean meal diet. 相似文献
105.
Forest responses to climate change in the northwestern United States: Ecophysiological foundations for adaptive management 总被引:1,自引:0,他引:1
Daniel J. Chmura Paul D. Anderson Glenn T. Howe Constance A. Harrington Jessica E. Halofsky David L. Peterson David C. Shaw J. Brad St.Clair 《Forest Ecology and Management》2011,261(7):1121-1142
Climate change resulting from increased concentrations of atmospheric carbon dioxide ([CO2]) is expected to result in warmer temperatures and changed precipitation regimes during this century. In the northwestern U.S., these changes will likely decrease snowpack, cause earlier snowmelt, increase summer evapotranspiration, and increase the frequency and severity of droughts. Elevated [CO2] and warmer temperatures may have positive effects on growth and productivity where there is adequate moisture or growth is currently limited by cold. However, the effects of climate change are generally expected to reduce growth and survival, predispose forests to disturbance by wildfire, insects, and disease; and ultimately change forest structure and composition at the landscape scale. Substantial warming will likely decrease winter chilling resulting in delayed bud burst, and adversely affect flowering and seed germination for some species. The extent of these effects will depend on the magnitude of climate change, the abilities of individual trees to acclimate, and for tree populations to adapt in situ, or to migrate to suitable habitats. These coping mechanisms may be insufficient to maintain optimal fitness of tree populations to rapidly changing climate. Physiological responses to climatic stresses are relatively well-understood at the organ or whole-plant scale but not at the stand or landscape scale. In particular, the interactive effects of multiple stressors is not well known. Genetic and silvicultural approaches to increase adaptive capacities and to decrease climate-related vulnerabilities of forests can be based on ecophysiological knowledge. Effective approaches to climate adaptation will likely include assisted migration of species and populations, and density management. Use of these approaches to increase forest resistance and resilience at the landscape scale requires a better understanding of species adaptations, within-species genetic variation, and the mitigating effects of silvicultural treatments. 相似文献
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108.
Veluchamy P Sivakumar PM Doble M 《Journal of agricultural and food chemistry》2011,59(20):10869-10878
Subtilisin was immobilized on polycaprolactam and used for food packaging applications to reduce the transference of microorganisms from the packaging material to the packaged food material. The optimized conditions for subtilisin immobilization was as follows: pH, 8; temperature, 4 °C; glutaraldehyde, 0.5%; incubation time, 25 h; and subtilisin concentration, 600 μL. The formation of -CH═N- at 1576 cm(-1) in the Fourier transform infrared (FTIR) spectrum confirmed the immobilization. Subtilisin-immobilized polycaprolactam (SIP) exhibited the highest residual activity of 106.67 ± 4.41% and 104.67 ± 0.88% at 40 °C and pH 8 and retained residual activity of 94% at the end of 56 days when compared to 21.33 ± 4.10% in the case of free subtilisin. SIP significantly (p < 0.05) lowered the colony forming units (CFU), dry weight, and protein and carbohydrate contents in bacterial and fungal biofilm. Practical application of the SIP on ham steaks at 4 and 20 °C showed a 2-3 times reduction of Staphylococcus aureus as well as Escherichia coli cells in the range of p < 0.05. 相似文献
109.
James W. Lloyd Stephen B. Harsh John B. Kaneene Gerald D. Schwab Brad J. Thacker Andrew J. Thulin 《Preventive veterinary medicine》1994,19(3-4):267-276
A study was designed to conduct an internal validation of a computerized systems model for health management decision support in growing hogs. Evaluation focused on both the alpha-beta tracker, which was employed to predict underlying system variables, and the simulation model itself, which predicted system performance. Both mean absolute prediction error and Theil's u2 statistic were calculated. Simulation scenarios were designed to highlight specific aspects of the model. In addition, a case example was developed to demonstrate the model's logical consistency and its applicability for assessing the economics of health management decisions. Use of the alpha-beta tracker to project data series, including pig deaths and disease prevalence rates at slaughter, was largely unsuccessful. The model consistently predicted hogs marketed such that 0 < u2 < 1. Also, decreased disease rates improved both physical and financial performance as expected. Depending on the quarter involved, the maximum bid to achieve a 50% decrease in the prevalence rates of pneumonia at slaughter and a 10% decrease in the prevalence rates of atrophic rhinitis at slaughter ranged from $0.15 to $0.37 per hog marketed for one producer. Future validation efforts should emphasize data quality and the effects of disease on production while seeking system application in a commercial production setting. 相似文献
110.
Lisa E Moore Laura D Garrett Brad Debey David S Biller 《Journal of the American Animal Hospital Association》2002,38(1):67-70
A 6-year-old, spayed female rottweiler was referred for left forelimb lameness followed by tetraparesis. A mast cell tumor compressing the spinal cord at the level of the sixth cervical to first thoracic (C6-T1) vertebrae was diagnosed based on cervical myelography and necropsy findings. This was considered a primary extracutaneous mast cell tumor, as no evidence of disease was found elsewhere. This is the first report of a primary mast cell tumor in this location. 相似文献