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81.
82.
Evaluation of T2‐weighted versus short‐tau inversion recovery sagittal sequences in the identification and localization of canine intervertebral disc extrusion with low‐field magnetic resonance imaging 下载免费PDF全文
Daniel Housley Abby Caine Giunio Cherubini Olivier Taeymans 《Veterinary radiology & ultrasound》2017,58(4):433-443
Sagittal T2‐weighted sequences (T2‐SAG) are the foundation of spinal protocols when screening for the presence of intervertebral disc extrusion. We often utilize sagittal short‐tau inversion recovery sequences (STIR‐SAG) as an adjunctive screening series, and experience suggests that this combined approach provides superior detection rates. We hypothesized that STIR‐SAG would provide higher sensitivity than T2‐SAG in the identification and localization of intervertebral disc extrusion. We further hypothesized that the parallel evaluation of paired T2‐SAG and STIR‐SAG series would provide a higher sensitivity than could be achieved with either independent sagittal series when viewed in isolation. This retrospective diagnostic accuracy study blindly reviewed T2‐SAG and STIR‐SAG sequences from dogs (n = 110) with surgically confirmed intervertebral disc extrusion. A consensus between two radiologists found no significant difference in sensitivity between T2‐SAG and STIR‐SAG during the identification of intervertebral disc extrusion (T2‐SAG: 92.7%, STIR‐SAG: 94.5%, P = 0.752). Nevertheless, STIR‐SAG accurately identified intervertebral disc extrusion in 66.7% of cases where the evaluation of T2‐SAG in isolation had provided a false negative diagnosis. Additionally, one radiologist found that the parallel evaluation of paired T2‐SAG and STIR‐SAG series provided a significantly higher sensitivity than T2‐SAG in isolation, during the identification of intervertebral disc extrusion (T2‐SAG: 78.2%, paired T2‐SAG, and STIR‐SAG: 90.9%, P = 0.017). A similar nonsignificant trend was observed when the consensus of both radiologists was taken into consideration (T2‐SAG: 92.7%, paired T2‐SAG, and STIR‐SAG = 97.3%, P = 0.392). We therefore conclude that STIR‐SAG is capable of identifying intervertebral disc extrusion that is inconspicuous in T2‐SAG, and that STIR‐SAG should be considered a useful adjunctive sequence during preliminary sagittal screening for intervertebral disc extrusion in low‐field magnetic resonance. 相似文献
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Olivier Brandenberger Dr Med Vet Fabrice Rossignol DVM Diplomate ECVS Antoine Lechartier DVM Diplomate ECVS Céline Mespoulhès‐Rivière DVM Diplomate ECVS Amelie Vitte DVM Anthony Rossignol Norm Ducharme DVM PhD Diplomate ACVS Karl Joseph Boening Dr Med Vet Diplomate ECVS 《Veterinary surgery : VS》2017,46(5):705-713
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Claudia Spadavecchia Olivier Levionnois Peter Kronen Ole K. Andersen 《Veterinary journal (London, England : 1997)》2010,183(3):337-344
The aim of this study was to quantify the effects of isoflurane at approximately the minimum alveolar concentration (peri-MAC) on the temporal summation (TS) of reflex activity in ponies. TS was evoked by repeated electrical stimulations applied at 5 Hz for 2 s on the digital nerve of the left forelimb of seven ponies. Surface electromyographic activity was recorded from the deltoid and common digital extensor muscles. TS thresholds and amplitude of response to stimulations of increasing intensities were assessed during anaesthesia at 0.85, 0.95 and 1.05 times the individual MAC, and after anaesthesia in standing animals. Under isoflurane anaesthesia, TS thresholds increased significantly in a concentration-dependent fashion and at each isoflurane MAC, the responses increased significantly for increasing stimulation intensities. A concentration-dependent depression of evoked reflexes with a reduction in the slopes of the stimulus–response function was observed for both muscles. The results demonstrated that with this model it is possible to describe and quantify the effects of anaesthetics on spinal sensory-motor processing in ponies. 相似文献
88.
Many northern hardwood understory plants have medicinal properties but their cost of production under conventional cultivation
practices is fairly high. Therefore wild harvesting continues putting the natural populations at risk. Their cultivation in
a forest farming system seems a promising alternative. This study was aimed at assessing the impact of canopy opening and
soil fertility on growth and active component production of four medicinal plants: black cohosh (Actaea racemosa), wild ginger (Asarum canadense), blue cohosh (Caulophyllum thalictroides) and bloodroot (Sanguinaria canadensis). Rhizome sections were planted in two sugar maple forests. Mortality and total leaf area were monitored during 3 years,
while subplots were harvested at the end of the second year for biomass and active component analyses. Multiple regressions
indicated that all species responded more to acidity related elements (pH, Al, Al + H, Fe, Zn) than to soil fertility (Ca,
K, Mg, P, C/N, base saturation and cation exchange capacity). This suggests that adjusting the pH by liming could be appropriate.
Growth increased with irradiance, except for blue cohosh, indicating that forest openings could also be part of an appropriate
forest management plan for their cultivation. While active component concentrations of rhizomes and roots increased in conditions
that negatively affected growth, such as low pH, soil fertility or light availability, their total active component content
exhibited responses that were similar to those of the growth variables. Thus, it seems that soil and light conditions that
favour the growth of these medicinal plants also favour their total yield in active components. 相似文献
89.
Amanda D. Bambrick Joann K. Whalen Robert L. Bradley Alain Cogliastro Andrew M. Gordon Alain Olivier Naresh V. Thevathasan 《Agroforestry Systems》2010,79(3):343-353
Land use affects the carbon sequestration potential of soils across landscapes. Tree-based intercropping (TBI) systems where
annual crops are grown between established tree rows are expected to exhibit spatial heterogeneity in the soil organic carbon
(SOC) content due to differences in carbon input and decomposition rates of litter from trees and herbaceous plants. This
study aimed to quantify variability in the SOC of TBI systems, compare the SOC content of TBI and nearby conventional agroecosystems,
and determine if SOC was related to soil fertility. The TBI research sites were established 4 years (St. Paulin and St. Edouard,
Quebec, Canada), 8 years (St. Remi, Quebec, Canada) and 21 years (Guelph, Ontario, Canada) before soil samples were collected
for this study. The SOC content was greater within 0.75 m of the tree row than in the intercropped space at the St. Edouard
and St. Remi sites. At the Guelph site, the SOC was spatially heterogeneous in plots with Norway spruce (Picea abies L.) but not hybrid poplar (Populus deltoides × P. nigra clone DN-177), probably due to litterfall distribution. Formerly a tree plantation, the TBI system at St. Remi contained
77% more SOC than a nearby conventional agroecosystem, while there was 12% more SOC in the TBI system than the conventional
agroecosystem at Guelph. There was no difference in the SOC content of 4-year old TBI sites and nearby conventional agroecosystems.
However, an increase in SOC at all TBI sites was positively related to the plant-available N concentrations, indicating the
benefit of temperate TBI systems for soil fertility. 相似文献
90.
Thibaut Olivier Vaidevutis Šveikauskas Elisabeth Demonty Kris De Jonghe Pascal Gentit Mojca Viršček-Marn Sabine Grausgruber-Gröger Sébastien Morio Francesco Faggioli Michèle Visage Frédéric Fauche Maria Gusina Marta Luigi Helena Lasner Irena Mavrič-Pleško 《European journal of plant pathology / European Foundation for Plant Pathology》2016,144(3):645-654