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The aim of the study was to determine identification, three-dimensional modelling, and morphometry of intracranial arteries in New Zealand Rabbit by using computed tomography angiography. A total of 20 adult New Zealand Rabbits from both sexes were used in the study. General anaesthesia procedure was followed before computed tomography angiography imaging. Rabbits were placed in a prone position for imaging. Computed tomography angiography imaging was performed by injecting contrast agent into vena auricularis marginalis of rabbits. Morphometric measurements of the specified points were taken by MIMICS program using the computed tomography angiography images acquired. Three-dimensional intracranial artery model was prepared from the two-dimensional images on the same program. Measurements were statistically compared in terms of sex and side. It was observed in the study that arteria basilaris was generated by bilateral arteria vertebralis at the basal level of medulla oblongata. In the study, a statistically significant difference was determined only in diameter values of arteria cerebri caudalis dextra et sinistra in both female and male rabbits. On the other hand, no statistically significant difference was determined with respect to the side. Consequently, we think that the data of the present study will contribute to further studies on cerebrovascular pathology, clinicians or researchers. 相似文献
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There are numerous publications about feline renal imaging information; however, none have established reference values for kidney size using computed tomography (CT). This study aimed to determine renal size and shape as well as the morphology of renal‐related structures in clinically normal cats (Felis catus) that underwent CT. Twenty‐seven healthy cats underwent pre‐ and post‐iodinated contrast‐enhanced CT. Most cat (59%) kidneys were located at the same level. The average pre‐contrast dimensions of the left kidney included a width of 2.46 ± 0.28 cm, a length of 3.52 ± 0.44 cm and a height 2.19 ± 0.31 cm, whereas those of the right kidneys were 2.45 ± 0.27 cm, 3.54 ± 0.46 cm and 2.05 ± 0.23 cm, respectively. After contrast enhancement, kidneys were slightly enlarged though not significantly. Additionally, renal length (LK or RK) was compared with second lumbar vertebra (L2) length and abdominal aorta diameter (AO). AO was significantly larger in male cats whereas L2 length appeared longer in male cats, but was not statistically different from the female cats. The LK/L2 and RK/L2 ratios were 2.29 ± 0.23 and 2.36 ± 0.20, respectively, and the LK/AO and RK/AO were 11.72 ± 1.37 and 12.05 ± 1.47, respectively. Renal vessels were examined. The renal vein was obviously larger than the renal artery, and paired renal veins were observed periodically. This study provides CT information about the feline kidney, which may help to establish reference values and information regarding renal structure prior to surgery in practice. 相似文献
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Srgio H. G. SILVA David C. WEINDORF Wilson M. FARIA Leandro C. PINTO Michele D. MENEZES Luiz R. G. GUILHERME Nilton CURI 《土壤圈》2021,31(4):615-626
Portable X-ray fluorescence (pXRF) spectrometry and magnetic susceptibility (MS) via magnetometer have been increasingly used with terrain variables for digital soil mapping. However, this methodology is still emerging in many countries with tropical soils. The objective of this study was to use proximal soil sensor data associated with terrain variables at varying spatial resolutions to predict soil classes using the Random Forest (RF) algorithm. The study was conducted on a 316-ha area featuring highly variable soil classes and complex soil-landscape relationships in Minas Gerais State, Brazil. The overall accuracy and Kappa index were evaluated using soils that were classified at 118 sites, with 90 being used for modeling and 28 for validation. Digital elevation models (DEMs) were created at 5-, 10-, 20-, and 30-m resolutions using contour lines from two sources. The resulting DEMs were processed to generate 12 terrain variables. Total Fe, Ti, and SiO2 contents were obtained using pXRF, with MS determined via a magnetometer. Soil class prediction was performed using the RF algorithm. The quality of the soil maps improved when using only the five most important covariates and combining proximal sensor data with terrain variables at different spatial resolutions. The finest spatial resolution did not always provide the most accurate maps. The high soil complexity in the area prevented highly accurate predictions. The most important variables influencing the soil mapping were MS, Fe, and Ti. Proximal sensor data associated with terrain information were successfully used to map Brazilian soils at variable spatial resolutions. 相似文献
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Taesik Yun Yoonhoi Koo Sanggu Kim Wonguk Lee Hakhyun Kim Dongwoo Chang Soochong Kim Mhan-Pyo Yang Byeong-Teck Kang 《The Veterinary quarterly》2021,41(1):163
An 8-year-old neutered male Yorkshire Terrier dog presented with head pressing, vestibular ataxia, neck tenderness, and no oculocephalic reflex. A demarcated lesion in the pons was identified on MRI. The patient was tentatively diagnosed with a glioma and was treated with hydroxyurea plus imatinib and prednisolone. After 30 days of therapeutic treatment, the patient showed a clear improvement in neurological signs, which lasted for 1117 days. On day 569 after the initiation of treatment, 18F-fluorodeoxyglucose (FDG)-positron emission tomography (PET) was performed with no significant findings on visual analysis. The average and maximal standardized uptake values (SUVs) were 1.92 and 2.29, respectively. The tumor-to-normal-tissue (T/N) ratio was 0.97. The first evidence of clinical deterioration was noticed on day 1147. On day 1155, 3,4-dihydroxy-6-[18F]-fluoro-l-phenylalanine (18F-FDOPA)-PET was performed. High uptake of 18F-FDOPA was observed in the intracranial lesion. The mean and maximal SUVs of the tumor were 1.59 and 2.29, respectively. The T/N ratio was 2.22. The patient was euthanized on day 1155 and histopathologic evaluations confirmed glioma (astrocytoma). This case shows that chemotherapy with hydroxyurea plus imatinib may be considered in the treatment of canine glioma. Furthermore, this is the first case describing the application of 18F-FDG and 18F-FDOPA in a dog with glioma. 相似文献