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91.
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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
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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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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
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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
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Tognolini M Giorgio C Hassan Mohamed I Barocelli E Calani L Reynaud E Dangles O Borges G Crozier A Brighenti F Del Rio D 《Journal of agricultural and food chemistry》2012,60(36):8877-8884
The Eph tyrosine kinase receptors and their ephrin ligands play a central role in human cancer as their deregulated expression induces tumorigenesis with aggressive phenotypes. To evaluate their potential contribution to EphA2-ephrinA1 modulation, several colonic catabolites of dietary (poly)phenolics, known to be generated in vivo, were screened using an ELISA-based binding assay. Some of the catabolites inhibited the binding in a dose-dependent manner (IC(50) values from 0.26 to 43 μM). Functional studies on prostate adenocarcinoma cells revealed that pyrogallol and protocatechuic acid specifically antagonized ephrinA1-Fc-induced EphA2 phosphorylation at concentrations that were not cytotoxic. The active concentrations of pyrogallol appear to be close to what can be reached in vivo under physiological conditions. Finally, because of the roles played by the Eph-ephrin system not only in cancer development but also in neurodegeneration and diabetes, pyrogallol and protocatechuic acid are candidates for more detailed functional studies to elucidate their role in these pathophysiological processes. 相似文献
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Coline Druart Maurice Millet Renaud Scheifler Olivier Delhomme Annette de Vaufleury 《Journal of Soils and Sediments》2011,11(8):1373-1384