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排序方式: 共有183条查询结果,搜索用时 234 毫秒
111.
Martina Becker Andreas Moritz Urs Giger 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》2008,37(4):373-384
Background: A CBC is an integral part of the assessment of health and disease in companion animals. While in the past newer technologies for CBC analysis were limited to large clinical pathology laboratories, several smaller and affordable automated hematology analyzers have been developed for in‐clinic use. Objectives: The purpose of this study was to compare CBC results generated by 7 in‐clinic laser‐ and impedance‐based hematology instruments and 2 commercial laboratory analyzers. Methods: Over a 3‐month period, fresh EDTA‐anticoagulated blood samples from healthy and diseased dogs (n=260) and cats (n=110) were analyzed on the LaserCyte, ForCyte, MS45, Heska CBC, Scil Vet ABC, VetScan HMT, QBC Vet Autoread, CELL‐DYN 3500, and ADVIA 120 analyzers. Results were compared by regression correlation (linear, Deming, Passing‐Bablok) and Bland–Altman bias plots using the ADVIA as the criterion standard for all analytes except HCT, which was compared with manual PCV. Precision, linearity, and carryover also were evaluated. Results: For most analytes, the in‐clinic analyzers and the CELL‐DYN performed similarly and correlated well with the ADVIA. The biases ranged from ?0.6 to 2.4 × 109/L for WBC count, 0 to 0.9 × 1012/L for RBC count, ?1.5 to 0.7 g/dL for hemoglobin concentration, ?4.3 to 8.3 fL for MCV, and ?69.3 to 77.2 × 109/L for platelet count. Compared with PCV, the HCT on most analyzers had a bias from 0.1% to 7.2%. Canine reticulocyte counts on the LaserCyte and ForCyte correlated but had a negative bias compared with those on the ADVIA. Precision, linearity, and carryover results were excellent for most analyzers. Conclusions: Total WBC and RBC counts were acceptable on all in‐clinic hematology instruments studied, with limitations for some RBC parameters and platelet counts. Together with evaluation of a blood film, these in‐clinic instruments can provide useful information on canine and feline patients in veterinary practices. 相似文献
112.
Jared A. Jaffey N. Scott Reading Urs Giger Osheiza Abdulmalik Ruben M. Buckley Sophie Johnstone Leslie A. Lyons 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2019,33(6):2725-2731
Two non‐pedigreed male castrated cats had persistent cyanosis over a 3‐year observation period. Clinical cardiopulmonary evaluations did not reveal abnormalities, but the blood remained dark after exposure to air. Erythrocytic methemoglobin concentrations were high (~40% of hemoglobin) and cytochrome b5 reductase (CYB5R) activities in erythrocytes were low (≤15% of control). One cat remained intolerant of exertion, and the other cat developed anemia and died due to an unidentified comorbidity. Whole‐genome sequencing revealed a homozygous c.625G>A missense variant (B4:137967506) and a c.232‐1G>C splice acceptor variant (B4:137970815) in CYB5R3, respectively, which were absent in 193 unaffected additional cats. The p.Gly209Ser missense variant likely disrupts a nicotinamide adenine dinucleotide (NADH)‐binding domain, while the splicing error occurs at the acceptor site for exon 4, which likely affects downstream translation of the protein. The 2 novel CYB5R3 variants were associated with methemoglobinemia using clinical, biochemical, genomics, and in silico protein studies. The variant prevalence is unknown in the cat population. 相似文献
113.
Michael G. Sorice Kiandra Rajala Urs P. Kreuter 《Strength and Conditioning Journal》2018,71(2):159-162
Ownership and management of North American rangelands has become increasingly diverse, prompting a need to better understand how changing demographics and values relate to individual land management decisions and land cover. Absentee landowners, who reside away from their rural property, are a growing segment of this changing social landscape. The implications of absentee ownership are not clearly understood, perhaps because the absentee concept is ambiguously defined and inconsistently specified. We introduce the construct of involvement with one’s land to clarify and reframe the absentee landowner concept. We analyzed data from a mail survey of rangeland owners in central Texas to explore the relationship between absentee land ownership and the use of brush management to restore woody-plant invaded grasslands. We employed an information-theoretic approach to compare candidate models using indicators of absenteeism (permanent residence on land and distance of permanent residence from land) and involvement. We measured involvement with one’s land as hours per week operating or working one’s land. We conducted path analysis to examine the relationship between absenteeism and brush management as a function of involvement. Involvement in land management was the best predictor of brush management behavior. Absenteeism, as measured through presence-absence or as distance from land, had no relationship with brush management unless mediated by the involvement construct. Segmenting landowners based solely on the location of their full-time residence provides little information on brush management behavior because it neglects the relationship that landowners may have with their land, regardless of residency. The absentee landowner concept is central to understanding the dynamics of rangeland management and important to get right. Our analysis suggests that getting it right means knowing more than the location of the residence of the landowner. 相似文献
114.
Rajan Parajuli Omkar Joshi Neelam C. Poudyal Urs P. Kreuter 《Strength and Conditioning Journal》2019,72(6):968-975
Prescribed burning is a widely used tool in forest and grassland management. However, because fire that escapes from a prescribed burn accidentally may cause property damage, injuries, and even human casualties, purchasing insurance to cover such damages may be beneficial for prescribed burn practitioners. Given that insurance coverage for prescribed fire is recently emerging, factors that determine burners’ decisions to purchase such insurance are largely unknown. On the basis of data from a survey of prescribed burn practitioners in 14 southern and midwestern states, we modeled prescribed burners’ likelihood of purchasing insurance with respect to demographic characteristics, land management objectives, and importance placed on regulatory compliance and land use practices. Results suggest that prescribed burn practitioners are more likely to obtain such insurance if they are landowners themselves or have a written prescribed burn plan. Age of respondents and the level of importance they place on compliance with environmental laws also had a significant positive effect on the likelihood of obtaining insurance coverage. Respondents were less likely to purchase insurance if their land management objective was to control invasive plants or they considered the availability of lower-cost alternatives for woody plant removal an important factor in deciding whether or not to conduct prescribed burns. These findings shed light on underlying factors influencing insurance coverage for prescribed burning and are potentially beneficial for promoting the acquisition of insurance among burn practitioners. 相似文献
115.
John R. Weir Urs P. Kreuter Carissa L. Wonkka Dirac Twidwell Dianne A. Stroman Morgan Russell Charles A. Taylor 《Strength and Conditioning Journal》2019,72(3):533-538
Changing climate and fuel accumulation are increasing wildfire risks across the western United States. This has led to calls for fire management reform, including the systematic use of prescribed fire. Although use of prescribed fire by private landowners in the southern Great Plains has increased during the past 30 yr, studies have determined that liability concerns are a major reason why many landowners do not use or promote the use of prescribed fire. Generally, perceptions of prescribed fire ? related liability are based on concerns over legal repercussions for escaped fire. This paper reviews the history and current legal liability standards used in the United States for prescribed fire, it examines how perceived and acceptable risk decisions about engagement in prescribed burning and other activities differ, and it presents unanticipated outcomes in two cases of prescribed fire insurance aimed at promoting the use of prescribed fire. We demonstrate that the empirical risk of liability from escaped fires is minimal (< 1%) and that other underlying factors may be leading to landowners’ exaggerated concerns of risk of liability when applying prescribed fire. We conclude that providing liability insurance may not be the most effective approach for increasing the use of prescribed fire by private landowners. Clearly differentiating the risks of applying prescribed fire from those of catastrophic wildfire damages, changing state statutes to reduce legal liability for escaped fire, and expanding landowner membership in prescribed burn associations may be more effective alternatives for attaining this goal. Fear of liability is a major deterrent to the use of prescribed fire; however, an evaluation of the risks from escaped fire does not support perceptions that using prescribed fire as a land management tool is risky. Prescribed burning associations and agencies that support land management improvement have an important role to play in spreading this message. 相似文献
116.
Short- and long-term patterns of net ecosystem carbon balance (NECB) for small, relatively uniform forest stands have been
examined in detail, but the same is not true for landscapes, especially those with heterogeneous disturbance histories. In
this paper, we explore the effect of two contrasting types of disturbances (i.e., fire and tree harvest) on landscape level
NECB by using an ecosystem process model that explicitly accounts for changes in carbon (C) stores as a function of disturbance
regimes. The latter were defined by the average disturbance interval, the regularity of the disturbance interval (i.e., random,
based on a Poisson frequency distribution, or regular), the amount of C removed by the disturbance (i.e., severity), and the
relative abundance of stands in the landscape with unique disturbance histories. We used the model to create over 300 hypothetical
landscapes, each with a different disturbance regime, by simulating up to 200 unique stand histories and averaging their total
C stores. Mean NECB and its year-to-year variability was computed by calculating the difference in mean total C stores from
one year to the next. Results indicated that landscape C stores were higher for random than for regular disturbance intervals,
and increased as the mean disturbance interval increased and as the disturbance severity decreased. For example, C storage
was reduced by 58% when the fire interval was shortened from 250 years to 100 years. Average landscape NECB was not significantly
different than zero for any of the simulated landscapes. Year-to-year variability in landscape NECB, however, was related
to the landscape disturbance regime; increasing with disturbance severity and frequency, and higher for random versus regular
disturbance intervals. We conclude that landscape C stores of forest systems can be predicted using the concept of disturbance
regimes, a result that may be a useful for adjusting estimates of C storage to broad scales that are solely based on physiological
processes. 相似文献
117.
Optimal coupling combinations between irrigation frequency and rate for drip-irrigated maize grown on sandy soil 总被引:1,自引:0,他引:1
This study was conducted over 2 years (2007 and 2008) to establish the optimal combinations between irrigation frequency and rate for drip-irrigated maize using water production functions and water use-yield relationships. A field experiment was conducted using a randomized complete block split plot design with four irrigation frequencies (F1, F2, F3 and F4, irrigation events once every 1, 2, 3 or 4 days, respectively) and three drip irrigation rates (I1: 1.00, I2: 0.80, and I3: 0.60 of the estimated evapotranspiration, ET) as the main and split plots, respectively. Our results show that yield variables and water use efficiencies (WUEs) increased with increasing irrigation frequency and rate, with non-significant differences between F1 and F2 in yield variables and between I1 and I2 in WUEs. Moreover, the combination between various irrigation frequencies and rates had an important effect on yield variables and WUEs, with the highest values being found for F1I2 and F2I1 and the lowest for F3I3 and F4I3. The F1I3 treatment had grain yield and yield components values similar to those obtained for the F3I2 and F4I1 treatments and WUEs values similar to those obtained for the F2I1 and F2I2 treatments. Seasonal yield response factors (ky) were 1.81 and 1.86 in 2007 and 2008, respectively. Production functions of yield versus seasonal crop ET were linear for all combinations of irrigation frequency and rate and for all irrigation frequency treatments with the exception of the F1 treatment, which instead showed a second order relationship. The relationship between WUE and grain yield was best represented by a power equation. In conclusion, we identified the optimal coupling combinations between irrigation frequency and water application rate to achieve the maximum yield and WUEs under either sufficient (F2I1) or limited irrigation (F1I3) water supplies. 相似文献
118.
Elizabeth A. Rozanski DVM Kenneth J. Drobatz DVM Dez Hugher BVSc Marry Scotti Mt Urs Giger DVM 《Journal of Veterinary Emergency and Critical Care》1999,9(2):73-78
In the veterinary literature, it has been suggested that a prolongation in the thrombotest (PIVKA test) is a sensitive and diagnostic indicator of anticoagulant rodenticide intoxication. We evaluated prothrombin time (PT), activated partial thromoplastin time (aPTT), and PIVKA indicator in 25 bleeding dogs: 7 with inherited coagulopathies. All dos with acquired coagulopathies had prolonged PIVKA values when compared to the normal controls. Factor VII deficient dogs had a prolonged PIVKA and PT test result, whereas dogs with intrinsic coagulopathies only had an aPTT prolongation. A three-fold increase of the PIVKA or PT values was highly suggestive of an anticoagulant rodenticide poisoning compared to other acquired coagulopathies. Prolonged PIVKA resuls were not specific for anticoagulant rodenticide intoxication in our group of bleeding dogs. 相似文献
119.
Ueli Braun DrMedVet Christoph Lischer DrMedVet Urs Koller DrMedVet Reudi Müller DrMedVet Urs Geissbühler DrMedVet 《Veterinary radiology & ultrasound》1999,40(2):162-163
This report describes the ultrasonographic and radiographic findings and the treatment of a Swiss Brown cow with a retropharyngeal abscess caused by improper administration of a magnet. 相似文献
120.