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191.
Thomas K. Day DVM MS DACVA DACVECC Carolyn R. Boyle PhD Merrilee Holland DVM DACVR 《Journal of Veterinary Emergency and Critical Care》2007,17(1):22-31
Objective and hypothesis: To determine whether or not there is agreement between the thermodilution and echocardiographic measurement of cardiac output (CO) during normovolemia and acute hemorrhage. The hypothesis was that there will be agreement between echocardiographic measurement of CO (ECO) and thermodilution measurement of CO (TDCO) during normovolemia and acute hemorrhage. Design: CO was measured by both thermodilution and echocardiography during α‐chloralose anesthesia in dogs before and 15 and 30 minutes following acute arterial hemorrhage. Setting: Laboratory investigation. Animals: Eighteen clinically healthy dogs, weighing 20–25 kg, anesthetized with α‐chloralose. Interventions: Acute arterial hemorrhage of approximately 50% of the total blood volume. CO was measured by thermodilution and echocardiography before and 15 and 30 minutes following hemorrhage. Measurements and main results: Acute hemorrhage resulted in a significant decrease in CO. There was a lack of agreement between the 2 methods to measure CO at each time and at all anatomic points of measurement in the aorta and pulmonary artery. Conclusion: There is a lack of agreement between the 2 methods; thus, determination of CO by echocardiography may not be a clinically useful tool following hemorrhage in dogs. 相似文献
192.
193.
Barbara Thuerig Andres Binder Thomas Boller Urs Guyer Sonia Jiménez Christina Rentsch Lucius Tamm 《European journal of plant pathology / European Foundation for Plant Pathology》2006,114(2):185-197
We have examined the effect of Pen, an aqueous extract of the dry mycelium of Penicillium chrysogenum, on plant–pathogen interactions. Pen controlled a broad range of pathogens on several crop plants under greenhouse and field
conditions. Pen protected grapevine from downy and powdery mildew (caused by Plasmopara viticola and Uncinula necator), tomato from early blight (caused by Phytophthora infestans), onion from downy mildew (Peronospora destructor) and apple trees from apple scab (caused by Venturia inaequalis) to a similar extent as fungicides such as copper and sulphur or well-known inducers such as benzothiadiazole or β-aminobutyric
acid. Pen had no major direct fungicidal effect and is thus supposed to protect plants by activating their defense mechanisms.
The raw material for extraction of Pen was available in constant quality, a prerequisite for commercial application. Under
certain conditions, Pen caused phytotoxic side effects. The symptoms mostly consisted of small necrotic spots or, more rarely,
of larger necrotic areas. The development of the symptoms was dependent on several parameters, including concentration of
Pen, the number of applications, the persistence on the plant tissue, the plant species and variety and environmental conditions.
In grapevine, a partially purified fraction of Pen was much less toxic than the crude Pen extract, but protected the plants
to a similar extent against P. viticola. Our data show that Pen has interesting and unique properties as a plant protection agent, but more research is needed to
further reduce its phytotoxic side effects. 相似文献
194.
Jrme Van Biervliet DVM Dipl ACVIM Marc Kraus DVM Dipl ACVIM Brett Woodie DVM Dipl ACVS Thomas J. Divers DVM Dipl ACVIM Dipl ACVECC Anna Gelzer Dr. Med. Vet. Dipl ACVIM Dorothy Ainsworth DVM PhD Dipl ACVIM 《Journal of Veterinary Cardiology》2006,8(1):69-73
A 5-year-old Holstein cow, pregnant with a valuable calf, was presented with signs of heart failure (tachycardia, peripheral edema, and distended jugular veins) related to pericardial lymphoma and associated cardiac tamponade. In addition, pleural effusion was present in both hemithoraces. Medical treatment, which consisted of repeated pericardiocenteses, placement of indwelling pleural catheters, administration of intravenous fluid therapy, antibiotics and anti-inflammatory drugs, was ineffective in controlling recurrence of clinical signs despite a temporary improvement. A standing thoracoscopic pericardiotomy was performed in an attempt to reduce clinical signs of heart failure and to prolong life. Clinical signs of heart failure abated and no recurrence was seen. Standing thoracoscopic pericardiotomy along with possible corticosteroids can be recommended as palliative treatment in an effort to extend life for reproductive performance in genetically valuable animals. 相似文献
195.
Cecil C. Konijnendijk Robert M. Ricard Andy Kenney Thomas B. Randrup 《Urban Forestry & Urban Greening》2006,4(3-4):93-103
Urban forestry is generally defined as the art, science and technology of managing trees and forest resources in and around urban community ecosystems for the physiological, sociological, economic, and aesthetic benefits trees provide society. First mentioned in the United States as early as in 1894, the concept underwent a revival during the 1960s as a comprehensive and interdisciplinary approach to the specific challenges related to growing trees in urban environments. Later, urban forestry evoked the interest of scientists and practitioners in other parts of the world. However, harmonization of urban forestry terminology has been complicated by, for example, the involvement of different disciplines and translation difficulties. In many European languages, for example, the direct translation of ‘urban forestry’ relates more to forest ecosystems than to street and park trees. Efforts in North America and Europe defining ‘urban forest’, ‘urban forestry’ and related terms are introduced. A comparative analysis of selected urban forestry terminology in both parts of the world shows that urban forestry has a longer history in North America, based on traditions of shade tree management. Moreover, urban forestry has become more institutionalized in North America. Urban forestry in Europe has built strongly on a century-long tradition of ‘town forestry’. In both parts of the world, definitions of urban forestry and urban forest have become more comprehensive, including all tree stands and individual trees in and around urban areas. Agreement also exists on the multifunctional and multidisciplinary character of urban forestry. These similarities offer opportunities for international harmonization of terminology. 相似文献
196.
Dead wood is a critical resource for biodiversity in boreal forests. We analysed the persistence of five model species inhabiting
dead wood. By parameterising a metapopulation model (the incidence function model), the model species were all assigned characteristics
that makes it likely that they have disappeared from some (20%) forest landscapes with a long history of forest management.
In the metapopulation model, a forest stand (5 ha) was regarded as a habitat patch. The amount of habitat in each patch was
obtained from models of dead wood dynamics of Norway spruce in central Sweden. Dead wood generated by altered management over
the entire landscape was found to be less efficient in reducing extinction risks in comparison to the same amount of dead
wood generated by protecting reserves. Because generation of dead wood by altered management is often less expensive than
setting aside reserves, it is difficult to determine which conservation measure is most cost-efficient. In a landscape subjected
to forestry for the first time, it was better to preserve a few large reserves than many small ones. However, in a managed,
highly fragmented forest landscape it was better to set aside many small reserves. The reason for this was that small plots
with high habitat quality could be selected, while large reserves originally contained habitats both of high and low quality,
and the rate of habitat quality increase was low. A strategy for biodiversity conservation in a managed forest landscape should
include information about the history of the landscape, the current amount and spatial distribution of forest habitats, and
the potential for rapid restoration of forest habitats, both on managed and unmanaged forest land. 相似文献
197.
Fabio C. Chaves Thomas J. Gianfagna 《Physiological and Molecular Plant Pathology》2007,70(4-6):174-179
Flavan-3-ol monomers and oligomers from dimers to decamers were quantitatively determined by HPLC-FLD in leaves of four Theobroma cacao varieties. Cacao flush leaves had higher procyanidin content than mature leaves. Moniliophthora perniciosa basidiospore infection results in an increase in cacao leaf procyanidins in the inoculated leaves, as well as in the uninoculated, adjacent, older leaves on an actively growing branch, resulting in both a local and systemic increase in procyanidin content in response to infection. Procyanidin oligomers increased significantly in leaves of the less susceptible genotype Scavina 6 upon infection, and total procyanidin levels were higher than in Cacao Comum a more disease susceptible genotype. Selection of genotypes with high constitutive and/or inducible content of procyanidins in young flush leaves may be a strategy to develop witches’ broom disease resistant cultivars. 相似文献
198.
The pink bollworm (PBW), Pectinophora gossypiella (Saunders) (Lepidoptera: Gelechiidae), is the key pest in cotton (Gossypium spp.) production areas in the southwestern United States and in many other cotton-producing areas of the world. The high costs of chemical control, continuing economic losses, secondary pest problems and environmental considerations suggest the need for ecologically oriented PBW management strategies. Extensive research has resulted in a broad array of monitoring, biological control, cultural, behavioural, genetic and host plant resistance methods that can serve as a base for the formulation of integrated PBW management systems. The life history characteristics of the PBW, in particular the high mobility of adults, indicate the need for combinations of selected integrated pest management (IPM) components implemented over large geographical areas. The areas involved present a wide range of PBW population densities, differences in cotton production methods and social and environmental considerations. The best option is tailor-made systems for targeted management areas with the selection of IPM components based on the PBW population density, crop production methods and economic feasibility. The unlikelihood of eradication indicates the need for long-term monitoring and programme maintenance following successful area-wide management. The success of area-wide PBW management is highly dependent on participation in the planning, site selection, implementation and assessment phases of the programme by all segments of the agricultural community. A highly effective extension--education communication programme is an essential component. Local uncoordinated efforts have not reduced the economic status of this pest in any area where it is an established pest. The potential long-term benefits of PBW population suppression on an area-wide basis appear to justify area-wide efforts in terms of reduced costs, more effective control, less environmental contamination and other peripheral problems associated with conventional control approaches. 相似文献
199.
Lyctia Zepeda Kenneth L. Buelow Kenneth V. Nordlund chester B. Thomas Michael T. Collins William J. Goodger 《Preventive veterinary medicine》1998,33(1-4):183-193
We used a linear programming model to estimate the financial returns to a Staphylococcus aureus testing and control program over a 1-year period for a 100-cow herd, with a 8636-kg rolling-herd average. Six tests, which vary in sensitivity from 0.80 to 0.98 and specificity of 0.99, were examined in simulated herds with 10, 20 and 30% prevalence of S. aureus infection. Sensitivity of these results to a range of assumptions regarding rolling-herd average, milk price, somatic cell-count premium, and cost and cure rate of dry treatment were examined to determine the profits from the program. The profits of a control program are most dependent upon prevalence, cell-count premium, and cost of dry treatment. In our simulation for a 100-cow herd, a testing and control program appears to cost less than US$10 per cow per year, and pays for itself within 1 yr, except under the lowest prevalence and most-adverse conditions (low yield, high cost of dry treatment, or low SCC premium). 相似文献
200.
Hereditary nephritis in the bull terrier: evidence for inheritance by an autosomal dominant gene 总被引:2,自引:0,他引:2
J C Hood W F Robinson C R Huxtable J S Bradley R J Sutherland M A Thomas 《The Veterinary record》1990,126(18):456-459
A high prevalence of renal failure has been reported in bull terriers in Australia. The pattern of inheritance was analysed in a family of 33 bull terriers in which 10 dogs had renal disease manifested by proteinuria, ultrastructural abnormalities in the glomerular basement membrane, renal failure, or 'end stage' kidneys. The presence of at least one affected parent for each affected offspring, the approximately equal male/female ratio and the apparent absence of 'generation-skipping', strongly supported an autosomal dominant mode of inheritance, assuming a fully penetrant single major gene locus. Further evidence was not compatible with either an autosomal recessive or X-linked inheritance pattern. This contrasts with the X-linked inheritance shown in Alport's-type human hereditary nephritis and hereditary glomerulopathy in the samoyeds. Hereditary nephritis in the bull terrier should be a useful model for non-Alport's-type human hereditary nephritis, which is also reported to have an autosomal dominant inheritance pattern. 相似文献