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排序方式: 共有503条查询结果,搜索用时 15 毫秒
451.
452.
STEVEN DE DECKER DVM INGRID M.V.L. GIELEN PhD LUC DUCHATEAU MSc PhD INGEBORGH POLIS PhD HENRI J.J. VAN BREE PhD Diplomate ECVDI & ECVS LUC M.L. VAN HAM PhD Diplomate ECVN 《Veterinary surgery : VS》2010,39(1):28-34
Objective— To evaluate agreement and repeatability of vertebral column measurements using computed tomography (CT) and magnetic resonance imaging (MRI).
Study Design— Retrospective observational study.
Animals— Dogs (n=18) with disc associated wobbler syndrome; Dog cadavers (n=3).
Methods— Five measurements of the 5th cervical vertebra were performed: vertebral body length (VBL), vertebral canal height (VCH), vertebral body height (VBH), vertebral canal width (VCW), and vertebral body width (VBW). Measurements were performed independently twice by 2 observers. Bland-Altman plots were created to evaluate agreement. Cadaveric vertebrae with soft tissue removed had the same variables and actual dimensions measured.
Results— The largest discrepancy between CT and MRI measurement was for VBL (mean difference±SD=1.262 mm±1.245; P <.001), with the difference for all the other variables being acceptable. The 1st measurement was significantly higher than the 2nd only for VBL using CT (mean difference=0.476 mm±1.120; P =.009), with all other variables having acceptable differences. Mean difference for all measurements between 2 observers was small, except for VBL using CT (mean difference=0.762 mm±1.042; P <.001). Only the difference for VBL between CT and cadaver specimens was statistically significant.
Conclusions— Our results suggest high repeatability and good agreement for most vertebral measurements of interest. VBL measurement using CT was considered problematic.
Clinical Relevance— Provided limitations are understood, linear measurements of vertebral dimensions from CT and MRI images can be used clinically. 相似文献
Study Design— Retrospective observational study.
Animals— Dogs (n=18) with disc associated wobbler syndrome; Dog cadavers (n=3).
Methods— Five measurements of the 5th cervical vertebra were performed: vertebral body length (VBL), vertebral canal height (VCH), vertebral body height (VBH), vertebral canal width (VCW), and vertebral body width (VBW). Measurements were performed independently twice by 2 observers. Bland-Altman plots were created to evaluate agreement. Cadaveric vertebrae with soft tissue removed had the same variables and actual dimensions measured.
Results— The largest discrepancy between CT and MRI measurement was for VBL (mean difference±SD=1.262 mm±1.245; P <.001), with the difference for all the other variables being acceptable. The 1st measurement was significantly higher than the 2nd only for VBL using CT (mean difference=0.476 mm±1.120; P =.009), with all other variables having acceptable differences. Mean difference for all measurements between 2 observers was small, except for VBL using CT (mean difference=0.762 mm±1.042; P <.001). Only the difference for VBL between CT and cadaver specimens was statistically significant.
Conclusions— Our results suggest high repeatability and good agreement for most vertebral measurements of interest. VBL measurement using CT was considered problematic.
Clinical Relevance— Provided limitations are understood, linear measurements of vertebral dimensions from CT and MRI images can be used clinically. 相似文献
453.
DINH VAN HUAN 《江西水产科技》2018,(3)
近年来,越南水产品(越南主要出口产品)的出口趋于稳定增长。经过20多年的发展,水产部门在提高增长质量、保护环境和满足其他重要的可持续性标准方面取得了重大进展。 相似文献
454.
S. A. HASSAN F. BIGLER P. BLAISINGER H. BOGENSCHÜTZ J. BRUN P. CHIVERTON E. DICKLER M. A. EASTERBROOK P. J. EDWARDS W. D. ENGLERT S. I. FIRTH P. HUANG C. INGLESFIELD F. KLINGAUF C. KÜHNER M. S. LEDIEU E. NATON P. A. OOMEN W. P. J. OVERMEER P. PLEVOETS J. N. REBOULET W. RIECKMANN L. SAMSOSE-PETERSEN S. W. SHIRES A. STÄUBLI J. STEVENSON J. J. TUSET G. VANWETSWINKEL A. Q. VAN ZON 《EPPO Bulletin》1985,15(2):214-255
455.
456.
457.
B. F. KANIA A. S. J. P. A. M. VAN MIERT 《Journal of veterinary pharmacology and therapeutics》1992,15(1):36-44
In sheep, beta-endorphin (1 and 2 micrograms/kg) administered into the third cerebral ventricle caused a significant inhibition of the frequency of rumen contractions. The amplitude of the first rumen contractions, following immediately after the end of infusion, and the average amplitude of primary rumen contractions, were inhibited. Beta-endorphin caused general psychomotor excitability. These results suggest that an inhibitory mu and delta opioid system is involved in the control of forestomach motility and general behaviour in sheep. All effects of beta-endorphin were completely prevented by i.c.v. 6-hydroxydopamine (6-OHDA, 18.2 micrograms/kg) pre-treatment. These results suggest that beta-endorphin-induced inhibition of rumen motility is due to central noradrenergic system activation. The exact location of this noradrenergic system remains to be determined. 相似文献
458.
459.
By means of microclectrophoresis in agar gel, we studied the hemolymph proteins of different species of the family Triatomidae (class Insecta) and different species of the families Ixodidae and Argasidae (clalss Arachnoidea). The results show a specific electrophoretic pattern for each species. Insects infected with pathogenic organisms have the same pattern as normal insects. 相似文献
460.
R. J. G. ZWIJNENBERG A. G. VULTO† A. S. J. P. A. M. VAN MIERT† J. T. LUMEIJ DVM PhD 《Journal of veterinary pharmacology and therapeutics》1992,15(4):364-378
Antibiotics and chemotherapeutics marketed for use in racing pigeons (Columba livia var. domestica) were evaluated by comparing the dosages and indications given by the manufacturers with the data obtained by pharmacokinetic, bacteriological and efficacy studies. This comparison showed that only three of the recommended dosages and indications of the 60 formulations marketed in The Netherlands are scientifically sound and in accordance with the literature. It is to be expected that the majority of the antimicrobials for pigeons will not satisfy the requirements for final registration as a pigeon therapeutic under the Dutch Veterinary Medicines Act of 1985. Several factors affecting drug availability are discussed, such as the different routes of administration and the influence of food. The public health aspects of the consumption of medicated pigeons is also discussed. Although there is no legislation with regard to this subject, a recommended withdrawal time of 10 days for the majority of the antimicrobials seems advisable. 相似文献