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121.
Alexander Valverde DVM DVSc Dip. ACVA M. Erin Hatcher DVM 《Journal of Veterinary Emergency and Critical Care》2008,18(5):480-487
Objective – To determine the effects of IV lactated Ringer's solution at a rate of 10 mL/kg/h in anesthetized dogs on total protein (TP) measurement and calculation of unmeasured anions (UAs) using 2 quantitative methods of acid‐base status determination, strong ion gap, and modified base deficit. Design – Prospective clinical study. Animals – Forty‐three dogs, anesthetic health status I or II according to the American Society of Anesthesiologists, undergoing surgery under general anesthesia. Interventions – Arterial blood analyses for gas tensions, acid‐base balance, electrolytes, lactate, hemoglobin (Hb), PCV, and TP were performed under general anesthesia immediately after induction and again after administration of approximately 10 mL/kg of lactated Ringer's solution (given over 1 h). UAs were determined using strong ion gap and modified base deficit. Measurements and Main Results – Fluid replacement for 1 hour decreased TP, Hb, and PCV by 8%, 7.8%, and 8.6%, respectively. The degree of decrease in TP did not impact the calculation of UAs by quantitative methods when the prefluid administration TP value was used instead of the postfluid TP value in the calculation. Comparison of the two methods showed a low correlation (r≤0.68) and marked differences in the precision (1.96 SD). Conclusions: The degree of decrease in TP after 1 hour of fluid replacement at approximately 10 mL/kg does not affect determination of UAs when prefluid TP is used within that time period. 相似文献
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Lesley A. Zwicker Andrea R. Matthews Etienne Côté Erin Andersen 《Veterinary radiology & ultrasound》2016,57(3):230-236
Dexmedetomidine, an alpha2‐adrenergic agonist, may be used in companion animals for chemical restraint, including cardiac evaluation. Echocardiographic changes associated with alpha2‐adrenergic agonists have been described; however reports of radiographic changes in cats were not found at the time of this study. Aims of this observational, prospective, experimental study were to describe the effects of dexmedetomidine on the radiographic appearance of the cardiac silhouette in healthy, adult cats. Fourteen healthy adult cats received dexmedetomidine 40 mcg/kg IM. Right lateral, left lateral, ventrodorsal, and dorsoventral thoracic radiographs were obtained for each cat at three time points: presedation, intrasedation, and postsedation (≥ two hours after reversal with atipamezole). Radiographs were evaluated in a blinded, randomized fashion by two independent observers using the vertebral heart score on all four views, the number of intercostal spaces on lateral projections, and the percent width of thorax on ventrodorsal and dorsoventral projections. Median vertebral heart score on right lateral view was significantly increased intrasedation (median = 7.8; range = 7.25–8.25) compared to presedation (median = 7.5; range = 7–8 [P = 0.001]). Median percentage width was significantly higher intrasedation (70% on VD; range 65–80 [P = 0.001], and 75% on DV; range 65–80 [P = 0.006]) compared to presedation (65%; range 65–75 on both projections). Dexmedetomidine was associated with a small but significant increase in cardiac silhouette size on right lateral (vertebral heart score), ventrodorsal (percentage width), and dorsoventral (percentage width) radiographs in healthy adult cats. This effect should be taken into consideration for future interpretation of thoracic radiographs in dexmedetomidine‐sedated cats. 相似文献
124.
Erin E. Beller Peter W. Downs Robin M. Grossinger Bruce K. Orr Micha N. Salomon 《Landscape Ecology》2016,31(3):581-600
Context
Effective river restoration requires understanding a system’s potential to support desired functions. This can be challenging to discern in the modern landscape, where natural complexity and heterogeneity are often heavily suppressed or modified. Historical analysis is therefore a valuable tool to provide the long-term perspective on riverine patterns, processes, and ecosystem change needed to set appropriate environmental management goals and strategies.Objective
In this study, we reconstructed historical (early 1800s) riparian conditions, river corridor extent, and dry-season flow on the lower Santa Clara River in southern California, with the goal of using this enhanced understanding to inform restoration and management activities.Method
Hundreds of cartographic, textual, and visual accounts were integrated into a GIS database of historical river characteristics.Results
We found that the river was characterized by an extremely broad river corridor and a diverse mosaic of riparian communities that varied by reach, from extensive (>100 ha) willow-cottonwood forests to xeric scrublands. Reach-scale ecological heterogeneity was linked to local variations in dry-season water availability, which was in turn underpinned by regional geophysical controls on groundwater and surface flow.Conclusions
Although human actions have greatly impacted the river’s extent, baseflow hydrology, and riparian habitats, many ecological attributes persist in more limited form, in large part facilitated by these fundamental hydrogeological controls. By drawing on a heretofore untapped dataset of spatially explicit and long-term environmental data, these findings improve our understanding of the river’s historical and current conditions and allow the derivation of reach-differentiated restoration and management opportunities that take advantage of local potential.125.
Michel P. Laforge Ryan K. Brook Floris M. van Beest Erin M. Bayne Philip D. McLoughlin 《Landscape Ecology》2016,31(4):855-863
Context
Spatial scale is an important consideration for understanding how animals select habitat, and multi-scalar designs in resource selection studies have become increasingly common. Despite this, examination of functional responses in habitat selection at multiple scales is rare. The perceptual range of an animal changes as a function of vegetation association, suggesting that use, selection and functional responses may all be habitat- and scale-dependent.Objectives
Our objective was to determine how varying grain size affects our interpretation of functional response in habitat selection and to elucidate scalar and landscape effects on habitat selection.Methods
We quantified the functional response of GPS-collared, female white-tailed deer (Odocoileus virginianus, n = 18) in Riding Mountain National Park, Canada, to different habitat types. Functional responses were quantified at multiple spatial scales by regressing proportion of habitat used against proportion of habitat available at different buffer radii (ranging from 75–1000 m radius) surrounding used (telemetry) locations and available points within the individual’s seasonal home range. We examined how functional responses changed as a function of grain by plotting grain size against the slope of the functional response.Results
We detected functional responses in most habitat types. As expected, functional responses tended to converge towards 1 (use proportional to availability) at large buffer sizes; however, the relationship between scale and functional response was typically non-linear and depended on habitat type.Conclusions
We conclude that a multi-scalar approach to modelling animal functional responses in habitat selection is important for understanding patterns in animal behaviour and resource use.126.
Dogs with acute myeloid leukemia or lymphoid neoplasms (large cell lymphoma or acute lymphoblastic leukemia) may have indistinguishable mediastinal masses on radiographs 下载免费PDF全文
Erin Epperly Kelly R. Hume Steven Moirano Tracy Stokol Joanne Intile Hollis N. Erb Peter V. Scrivani 《Veterinary radiology & ultrasound》2018,59(5):507-515
Acute myeloid leukemia is an uncommon hematopoietic neoplasm of dogs that should be differentiated from lymphoid neoplasms, such as lymphoma, because of different treatment protocols and a worse prognosis. Thoracic radiography is performed frequently in dogs with suspected hematopoietic neoplasia, and detecting a mediastinal mass often prioritizes lymphoma as the most likely diagnosis. However, we have observed a mediastinal mass in several dogs with acute myeloid leukemia and hypothesized that (1) the frequency of a mediastinal mass was higher and (2) the size of the mass was larger in dogs with acute myeloid leukemia compared to dogs with lymphoid neoplasms. In this analytical study (observational, retrospective, and cross‐sectional), the sample population included 238 dogs with hematopoietic neoplasia. These dogs were divided into lymphoid (large cell lymphoma, acute lymphoblastic leukemia) and myeloid groups based on standard phenotyping tests. A mediastinal mass was detected during thoracic radiography in 73/218 (33%) and nine of 20 (45%) dogs in the lymphoid and myeloid groups (P = 0.21), respectively. The median size ratio of mediastinal mass to cardiac silhouette was 0.20 and 0.23 in the lymphoid and myeloid groups (P = 0.96), respectively. Additionally, we observed normal thoracic radiographs in 111/218 (51%) dogs in the lymphoid group and nine of 20 (45%) dogs in the myeloid group. In conclusion, acute myeloid leukemia should be considered when a mediastinal mass is detected during radiography in dogs with suspected hematopoietic neoplasia—but the presence or size of a mediastinal mass does not differentiate between myeloid and lymphoid neoplasms. 相似文献
127.
Erin Ciwko Miranda J. Sadar Katarina Bennett Kathleen Linn 《Journal of Exotic Pet Medicine》2018,27(4):31-37
Two male intact dwarf rabbits (Oryctolagus cuniculus), 20 and 26 months old, were diagnosed with traumatic long bone fractures of the radius/ulna and tibia, respectively. Transfixation pin splinting, a technique adapted from large animal orthopedics, was used to stabilize the long bone fractures in both rabbits. Bony union with return to normal limb function was achieved in both cases within 6 weeks. The 2 cases were followed for up to 14 months after surgery, and each patient's affected leg returned to normal function. Transfixation pin splints can provide a safe and effective alternative to traditional small animal fracture repairs in domestic rabbits. 相似文献
128.
M. Andrew Stamper Michele M. Kittell Erin E. Patel Allison L. Corwin 《Journal of aquatic animal health》2013,25(3):111-116
Abstract Head and lateral line erosion syndrome (HLLES) is a common but very poorly understood disease of marine aquarium fish. One suspected etiology is the use of granulated activated carbon (GAC) to filter the water. Seventy-two ocean surgeons Acanthurus bahianus were distributed among three carbon-negative control systems and three GAC-treated systems such that each tank contained approximately the same total body mass. Each replicate system was made up of two 250-L circular tanks with a common filtration system (6 fish per tank, 12 fish per replicate system). The GAC-treated tanks were exposed to full-stream, extruded coconut shell activated carbon, which produced a mean total organic carbon content of 0.4 mg/L. The results of this study indicate that extruded coconut shell activated carbon filtering at full-stream rates can cause HLLES-type lesions in ocean surgeons. The HLLES developed exponentially over 15 d, beginning in the chin region. This was followed by pitting in the cheek region, which expanded until erosions coalesced. Once the carbon was discontinued, the processes reversed in a mean time of 49 d. As the lesions healed, they reverted from the coalesced to the pitted stage and then darkened before returning to normal. Received September 2, 2010; accepted March 20, 2011 相似文献
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