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31.
Piper L. Wall DVM PhD † Akella Chendrasekhar MD †Gregory A. Timberlake MD † 《Journal of Veterinary Emergency and Critical Care》1998,8(2):109-115
The accuracy and precision of an end-tidal infrared CO2 monitor and customized capnography tubing system designed to measure gastrointestinal intraluminal CO2 partial pressure (Pi CO2 ) were tested in vitro. Samples were taken from the customized capnography tubing placed in either 5% or 10% CO2 gas at discrete intervals ranging from one minute to twelve minutes. For a given time interval, the tubing PCO2 measurement was a constant fraction of the actual PCO2 (all standard errors < 0.02). For increasing time intervals, the ratio of the tubing PCO2 to actual PCO2 increased logarithmically. In the 5% and 10% CO2 , the regression coefficients were 0.89 and 0.85 for 8 French tubing and 0.99 and 0.91 for 6 French tubing. Beacuase of its accuracy and precision, this system may provide automated gastrointestinal CO2 partial pressure monitoring at short intervals (e.g. 5 minutes), facilitating testing of the role of gastrointestinal Pi CO2 information in treatment algorithms. (Vet Emerg & Crit Care, 1998; 8: 109–116) 相似文献
32.
Angular deformities of 25 or 37 degrees valgus were created by transverse wedge osteotomies in the diaphysis of the radius in 3-month-old Cocker Spaniels. Spontaneous correction was judged from radiographs until skeletal maturity. The magnitude of correction was estimated, using the opposite normal leg as a control. Asymmetrical physeal growth corrected the induced angulation between the proximal and distal radial joint plane surfaces (joint plane angle). The average correction of the joint plane angle was 80% in the 25 degree group, and 72% in the 37 degree group. Bone remodeling of the radial shaft corrected the induced diaphyseal angulation by 50% in both groups during the study. 相似文献
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35.
Grady H. Shelton DVM Chris K. Grant PhD DSc Michael L. Linenberger MD Janis L. Abkowitz MD 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》1990,4(6):317-319
Griseofulvin administration was associated with the development of absolute neutropenia in six of seven (86%) cats with feline immunodeficiency virus (FIV) infection. The neutropenia was severe (less than 400 neutrophils/microliter) in four of the six affected cats, and one cat died from sepsis. Neutrophil counts returned to baseline values within 15 days after drug withdrawal in all surviving cats. No symptoms or hematologic abnormalities were observed in four normal (FIV-seronegative) cats treated with the same lot of griseofulvin at equivalent doses. Neutropenia recurred in two of two FIV-seropositive cats upon griseofulvin rechallenge. Cats with FIV infections appear to be at increased risk for griseofulvin-associated neutropenia. This phenomenon may be analogous to the increased frequency of antibiotic-induced neutropenias observed in humans infected with the human immunodeficiency virus. 相似文献
36.
ALAN B. KUZMA BSc DVM DVSc DAVID L. HOLMBERG DVM MVSc DiplomateACVS CRAIG W. MILLER DVM MSc DiplomateACVS IAN BARKER DVM MSc PhD JAMES ROTH MD FRCS 《Veterinary surgery : VS》1990,18(6):439-445
An orthotopic colon graft based on the middle colic artery and vein was implanted with microvascular technique and a stapling instrument in five dogs. The grafts were successful in four dogs. A similar colon autograft was used to replace the entire thoracic esophagus in five dogs. The recipient vessels were the left carotid artery and left external jugular vein. Four of the grafts failed because of kinking and thrombosis of the arterial supply (2 dogs) or the venous outflow (2 dogs). One graft, which had a viable vascular supply, developed a severe leak at the colon-to-stomach anastomosis, and the dog was euthanatized on day 3. The recipient vascular pedicle was modified and used successfully to replace a portion of the cervical esophagus in three dogs. The grafts survived, the dogs could swallow liquids and semisolid food well, and, at necropsy after 4 weeks, the anastomotic sites were well healed. The graft sites contained essentially normal colon mucosa. 相似文献
37.
Abstract – Effects of local environmental influences on the structure of fish assemblages were evaluated from 159 sites in two regions of the Great Plains with limited anthropogenic disturbance. These regions offered an opportunity to evaluate the structure and variation of streams and fish assemblages within the Great Plains. We used canonical correspondence analyses to determine the influence of environmental conditions on species abundances, species occurrences and assemblage characteristics. Analysis of regions separately indicated that similar environmental factors structured streams and fish assemblages, despite differences in environmental conditions and species composition between regions. Variance in fish abundance and assemblage characteristics from both regions was best explained by metrics of stream size and associated metrics (width, depth, conductivity and instream cover). Our results provide a framework and reference for conditions and assemblage structure in North American prairie streams. 相似文献
38.
Summary Wood storage has a great influence on the efficiency of a pulpmill. Great problems arise when using outside chip storage, especially in processing hardwoods, in that hardwood chips discolorate after a few days, which is not the case with spruce chips. The causes of such a different behavior of beech and spruce were investigated. It could be shown that a sufficient amount of active peroxidase, malate dehydrogenase and oxygen are prerequisites for the formation of phenoxy radicals within the beech lignin. This causes formation of new chromophores that discolorize the wood. Sufficient amounts of such enzymes are present in beech wood after harvesting. 相似文献
39.
Stefan Fleck Nathalie Cools Bruno De Vos Henning Meesenburg Richard Fischer 《Annals of Forest Science》2016,73(4):945-957
Key message
Aggregated, consolidated, and derived soil physicochemical data of 286 ICP Forests Level II plots were completed with soil hydraulic properties for integrated use with forest monitoring data. Database access should be requested at http://icp-forests.net . Metadata associated available at https://metadata-afs.nancy.inra.fr/geonetwork/apps/georchestra/?uuid=153e599e-6624-4e2b-b862-8124386ea9cd&hl=engContext
The ICP Forests database is one of the most comprehensive forest ecosystem datasets in Europe and contains the accumulated results of more than two decades of harmonised forest monitoring all over Europe.Aims
The aim of this paper is to share knowledge on the ICP Forests Level II soil data for broader use among forest scientists.Methods
After standard analysis, quality checks, aggregation, and calculation of derived variables (e.g. nutrient stocks, base saturation, C:N ratio, and water retention parameters), data have been gathered into a static database (AFSCDB.LII.2.2), which will be updated to new versions as soon as new measurements become available.Results
The database provides a basis for the combined evaluation of up to 130 unique soil variables of 286 plots with dynamic data on tree growth, ground vegetation, foliar chemistry, crown condition, tree phenology, leaf area index, ozone injury, litterfall, soil solution chemistry, deposition, ambient air quality, and meteorological data assessed on the same plots.Conclusion
The unprecedented comprehensiveness and level of detail in this newly aggregated database may overcome existing restrictions so far impeding the realisation of large-scale forest ecosystem studies in Europe.40.
Smallholder perceptions of agroforestry projects in Panama 总被引:7,自引:1,他引:7
The potential effects of agroforestry systems on conservation and development have been well documented. Panama has seen a
substantial rise in the number of projects with an agroforestry component in the 1990s. There has been insufficient research
on the actual impacts of these projects on smallholders and of farmers' attitudes towards these systems. This study explores
the perceived socioeconomic and environmental impacts of five agroforestry projects in Panama. A total of 68 smallholders
were administered semi-structured interviews. In addition, 13 agroforestry experts from NGOs, government departments and research
institutes were interviewed, and their responses were compared with those of the smallholders. While the projects led to an
increase in the standard of living by providing wood products and fruit for domestic consumption, farm income levels generally
remained unchanged. This was due primarily to limited market development, the lack of marketing organizations and poor access
roads. In terms of environmental impacts, the farmers' responses suggested a slight decline in slash-and-burn agriculture,
and an increase in tree planting activities. Some environmental benefits were observed by farmers, including reduced soil
erosion, increased soil fertility, and improved quality and quantity of water sources. Nevertheless, slash-and-burn agriculture
was still the norm for the majority of farmers. Most farmers continued to harvest wood from primary and secondary growth to
meet their domestic wood requirements, rather than relying on trees planted in agroforestry projects. The main obstacles preventing
increased agroforestry adoption included insufficient agroforestry extension, inappropriate project design or management (such
as top-down management approaches, and the use of food incentives), smallholders' economic constraints, and larger policy
issues. Recommendations are proposed to improve project design and management, and to address the economic and policy constraints.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献