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201.
Mary B. Mahaffey DVM MS Don L. Barber DVM MS Jeanne A. Barsanti DVM MS Wayne A. Crowell DVM PhD 《Veterinary radiology & ultrasound》1984,25(6):254-259
Double-contrast cystograms and cystometrograms were performed simultaneously in each of six male and six female dogs with normal urinalyses. The dogs were sedated with oxymorphone and acepromazine. Detrusor reflex occurred in 11 of 12 dogs. After bladder infusion of 0.88 ml/kg of positive-contrast medium, there was mucosal irregularity in eight of 12 dogs and bladder shape distortion in 12 of 12 dogs. Bladder distortion decreased with progressive infusion of CO2 , and mucosal irregularity was eliminated after infusion of 50–100 ml CO2 . The bladder neck in all dogs was initially located within the pelvic canal. In ten of 12 dogs, the bladder neck was cranially displaced when the bladder was fully distended. Bladder wall thickness was approximately 1 mm circumferentially at all degrees of distention. There was no discernible difference between bladder shape prior to and at initiation of contraction. It was concluded that radiographic determination of a normal urinary bladder can be made without complete bladder distention and that cystograms and cystometrograms can be routinely performed simultaneously in dogs in which both procedures are required. 相似文献
202.
Stewart-Johnson Alva Dziva Francis Abdela Woubit Rahaman Saed Adesiyun Abiodun 《Tropical animal health and production》2019,51(2):369-372
Tropical Animal Health and Production - Livestock-associated methicillin-resistant Staphylococcus aureus (LA-MRSA) is a cause of zoonotic infections in many countries. People with occupational... 相似文献
203.
Maldwyn John Evans Sam C. Banks Kendi F. Davies Jeff Mcclenahan Brett Melbourne Don A. Driscoll 《Landscape Ecology》2016,31(8):1815-1831
Context
Edge effects due to habitat loss and fragmentation have pervasive impacts on many natural ecosystems worldwide.Objective
We aimed to explore whether, in tandem with the resource-based model of edge effects, species feeding-guild and flight-capacity can help explain species responses to an edge.Methods
We used a two-sided edge gradient that extended from 1000 m into native Eucalyptus forest to 316 m into an exotic pine plantation. We used generalised additive models to examine the continuous responses of beetle species, feeding-guild species richness and flight-capable group species richness to the edge gradient and environmental covariates.Results
Phytophagous species richness was directly related to variation in vegetation along the edge gradient. There were more flight-capable species in Eucalyptus forest and more flightless species in exotic pine plantation. Many individual species exhibited multiple-peaked edge-profiles.Conclusions
The resource based model for edge effects can be used in tandem with traits such as feeding-guild and flight-capacity to understand drivers of large scale edge responses. Some trait-groups can show generalisable responses that can be linked with drivers such as vegetation richness and habitat structure. Many trait-group responses, however, are less generalisable and not explained by easily measured habitat variables. Difficulties in linking traits with resources along the edge could be due to unmeasured variation and indirect effects. Some species’ responses reached the limits of the edge gradient demonstrating the need to examine edge effects at large scales, such as kilometres.204.
205.
Recent technological advances mean that samples from animal experiments may be analysed more cheaply, more easily and with a much greater return of data than previously. Research groups are frequently faced with a choice of continuing to use established technology in which they may have made a significant investment of time and resources, and have significant amounts of reference data, or switching to new technology where reference data may be limited. Apart from cost, the choice needs to be based on a comparison between the increase in data available from future experiments by switching and the value of comparison with reference data from historical experiments analysed with earlier technology. One approach to this problem is to ensure that sufficient quantity and variety of samples are taken from each experiment and appropriately stored to allow re-establishment of a sufficiently large reference set and to avoid the need to repeat animal experiments. The establishment of ‘biobanks' of experimental material will require funding for infrastructure, consistent storage of metadata and, importantly,horizon-scanning to ensure that samples are taken appropriately for techniques which will become accessible in future. Such biobanks are a recognised resource in human medicine, where the value of samples increases as more analysis is carried out and added to the metadata. 相似文献
206.
Potential exposure to Australian bat lyssavirus is unlikely to prevent future bat handling among adults in South East Queensland 下载免费PDF全文
M. K. Young S. Banu B. J. McCall S. Vlack H. Carroll S. Bennett R. Davison D. Francis 《Zoonoses and public health》2018,65(1):e237-e242
Despite ongoing public health messages about the risks associated with bat contact, the number of potential exposures to Australian bat lyssavirus (ABLV) due to intentional handling by members of the general public in Queensland has remained high. We sought to better understand the reasons for intentional handling among these members of the public who reported their potential exposure to inform future public health messages. We interviewed adults who resided in a defined geographic area in South East Queensland and notified potential exposure to ABLV due to intentional handling of bats by telephone between 1 January 2012 and 31 December 2013. The participation rate was 54%. Adults who reported they had intentionally handled bats in South East Queensland indicated high levels of knowledge and perception of a moderately high risk associated with bats with overall low intentions to handle bats in the future. However, substantial proportions of people would attempt to handle bats again in some circumstances, particularly to protect their children or pets. Fifty‐two percent indicated that they would handle a bat if a child was about to pick up or touch a live bat, and 49% would intervene if a pet was interacting with a bat. Future public health communications should recognize the situations in which even people with highrisk perceptions of bats will attempt to handle them. Public health messages currently focus on avoidance of bats in all circumstances and recommend calling in a trained vaccinated handler, but messaging directed at adults for circumstances where children or pets may be potentially exposed should provide safe immediate management options. 相似文献
207.
208.
Marron N Villar M Dreyer E Delay D Boudouresque E Petit JM Delmotte FM Guehl JM Brignolas F 《Tree physiology》2005,25(4):425-435
To test if some leaf parameters are predictors of productivity in a range of Populus deltoides (Bartr.) Marsh. x P. nigra L. clones, we assessed leaf traits and productivity in 2-month-old rooted cuttings from 31 clones growing in 4-l pots in a greenhouse, under conditions of controlled temperature and optimal irrigation. We evaluated four groups of variables describing (1) productivity (total biomass), (2) leaf growth (total leaf number increment and total leaf area increment rate), (3) leaf structure (specific leaf area and nitrogen and carbon contents) and (4) carbon isotope discrimination (delta), which is negatively correlated with time-integrated water-use efficiency. High-yielding clones did not necessarily display high leaf growth rates, but they displayed a larger total leaf area, lower specific leaf area and lower leaf nitrogen concentration than clones with low productivity. Total leaf area was mainly controlled by maximal individual leaf area and total leaf area increment rate (r = 0.51 and 0.56, respectively). Carbon isotope discrimination did not correlate with total biomass, but it was associated with total number of leaves and total leaf area increment rate (r = 0.39 and 0.45, respectively). Therefore, leaf area and specific leaf area were better indicators of productivity than leaf growth traits. The observed independence of delta from biomass production provides opportunities for selecting poplar clones combining high productivity and high water-use efficiency. 相似文献
209.
Qingjiang Hou James Brandle Kenneth Hubbard Michele Schoeneberger Carlos Nieto Charles Francis 《Agroforestry Systems》2003,57(2):137-147
Root-pruning is generally recommended as an appropriate treatment to reduce competition for soil water and/or nutrients and suppression of crop yield in areas adjacent to windbreaks. Several recent studies suggest, however, that factors other than soil water might be causing yield reduction at the interface. For two consecutive years, we evaluated root-pruning effects on soil water at the windbreak/crop interface under both cropped (soybean [Glycine max (L) Merr.] variety Iroquois, 1997) and non-cropped (1998) conditions in Mead, Nebraska, USA. Volumetric soil water content near the windbreaks was systematically measured at various soil depths, distances from the windbreak, and windbreak exposures using Time Domain Reflectometry (TDR). Overall differences in soil water content between root-pruned and non-pruned plots in soybean were smaller in magnitude at all distances in both the west (windbreak on the east side) and the east (windbreak on the west side) exposures in 1997, compared with the non-cropped condition in the south exposure in 1998. With a soybean crop in 1997, volumetric soil water content in the east exposure averaged 2.3% greater in the top 30 cm of the soil profile at a distance of 0.75H (H = windbreak height) into the field from the windbreak when compared to the non-pruned treatment. In the west exposure, however, the differences were undetectable at corresponding distance and depth. The increase in soybean yield in root-pruned plots corresponded well with the observed differences in soil water content at various distances, especially in the east exposure. Under a non-cropped condition in 1998, soil water content in the root-pruned plots was significantly greater than the non-pruned plots in the top 45-cm profile, averaging 3.3% at 0.75H and 2.2% at 1.0H. Beyond 1.0H, the increase was not significant. These results agree with the previously reported range of crop yield suppression near windbreaks, indicating that soil water competition between the crop and windbreak is highly related to, and probably plays a leading role in yield suppression within the competition zone.This revised version was published online in November 2005 with corrections to the Cover Date. 相似文献
210.
We offer a critique of Canada's approach to domestic food security with respect to international agreements, justiciability and case law, the breakdown of the public safety net, the institutionalisation of charitable approaches to food insecurity, and the need for 'joined-up' food and nutrition policies. We examined Canada's commitments to the right to food, as well as Canadian policies, case law and social trends, in order to assess Canada's performance with respect to the human right to food. We found that while Canada has been a leader in signing international human rights agreements, including those relating to the right to food, domestic action has lagged and food insecurity increased. We provide recommendations for policy changes that could deal with complex issues of state accountability, social safety nets and vulnerable populations, and joined-up policy frameworks that could help realise the right to adequate food in Canada and other developed nations. 相似文献