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排序方式: 共有277条查询结果,搜索用时 15 毫秒
271.
Pablo Amengual-Batle Roberto José-López Alexane Durand Michal Czopowicz Elsa Beltran Julien Guevar Kali Lazzerini Steven De Decker Karen Muñana Peter Early Christopher Mariani Natasha Olby Nicholas Petrovitch Rodrigo Gutierrez-Quintana 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2020,34(5):1975-1985
272.
Marina J. Nyqvist Julien Cucherousset Rodolphe E. Gozlan William R.C. Beaumont J. Robert Britton 《Ecology of Freshwater Fish》2020,29(2):377-383
Individual variability in dispersal strategies, where some individuals disperse and others remain resident, is a common phenomenon across many species. Despite its important ecological consequences, the mechanisms and individual consequences of dispersal remain poorly understood. Here, riverine Northern pike (Esox lucius) juveniles (age 0+ (young-of-the-year) and 1+ years) were used to investigate the influence of body size and trophic position (at capture) on the dispersal from off-channel natal habitats and the subsequent consequences for body sizes, specific growth rate and trophic position (at recapture). Individuals that dispersed into the river (“dispersers”) were not significantly different in body size than those remaining on nursery grounds (“stayers”). For trophic position, 0+ dispersers were of significantly lower trophic position than stayers, but with this not apparent in the 1+ fish. Following dispersal into the river, the dispersers grew significantly faster than stayers and, on recapture, were significantly larger, but with no significant differences in their final trophic positions. Early dispersal into the river was, therefore, not associated with early dietary shifts to piscivory and the attainment of larger body sizes of individuals whilst in their natal habitats, contrary to prediction. These results suggest that despite an increasing risk of mortality for individuals dispersing early from natal areas, there are long-term benefits via elevated growth rates and, potentially, higher fitness. Such early dispersal behaviour could be driven by early competitive displacement. 相似文献
273.
Julien Fages Trisha J. Oura James Sutherland‐Smith Samuel H. Jennings 《Veterinary radiology & ultrasound》2020,61(1):40-47
Canine intracranial meningiomas can be graded based on histological classification as benign (grade I), atypical (grade II), and anaplastic or malignant (grade III). In people, grade II/III meningiomas behave more aggressively, have a higher potential for recurrence after surgical resection, and have lower apparent diffusion coefficient (ADC) values with diffusion weighted imaging (DWI). In this retrospective analytical cross‐sectional study, 42 dogs had ADC values quantified in an attempt to differentiate tumor histologic grade. Our hypothesis was that ADC values would be significantly lower in grade II and III versus grade I meningiomas in dogs. On each ADC image, a polygonal region of interest (ROI) was hand‐drawn along the lesion's periphery, excluding fluid‐filled and hemorrhagic regions. Mean ADC value (ADCmean) and minimum ADC value (ADCmin) were calculated. Additionally, two smaller, ovoid ROI were drawn within the lesion with mean ADC calculated (ADCmean sR and ADCmin sR). Normalized ADC values using white matter were also calculated (ADCn and ADCn sR). Grades of each tumor were assigned based on histopathology review. Association between ADC parameters and histological grade was tested by means of two‐sample t‐tests. There were 14 grade I (33.3%), 25 grade II (59.5%), and three grade III (7.2%) meningiomas. ADCmean sR and ADCmin sR were significantly lower when comparing grade II/III to grade I (P < .05). Grade II tumors had significantly lower ADCmean, ADCmean sR, ADCmin sR, ADCn, and ADCn sR than grade I meningiomas. This preliminary study supports the potential of ADC values to help predict the histological grade of intracranial meningiomas in dogs. 相似文献
274.
Chiara Mattei Anna Oevermann Daniela Schweizer Julien Guevar Thomas W. Maddox Kathryn L. Fleming Emanuele Ricci Marco Rosati Roberta Biserni John F. Griffin IV Angie Rupp Rodrigo Gutierrez-Quintana Isabelle Masseau Kimberly M. Newkirk Silke Hecht Swan Specchi 《Veterinary radiology & ultrasound》2023,64(2):294-305
Intravascular lymphoma (IVL) is characterized by the proliferation of large malignant lymphocytes within the lumen of blood vessels. This retrospective, multi-center, case series study aimed to describe the MRI features of confirmed central nervous system IVL in dogs and compare them with histopathological findings. Medical record databases from seven veterinary centers were searched for cases of histologically confirmed IVL. Dogs were included if an MRI was performed. The MRI studies and histopathology samples were reviewed to compare the MRI changes with the histopathological findings. Twelve dogs met the inclusion criteria (12 brains and three spinal cords). Imaging of the brains revealed multifocal T2-weighted/FLAIR hyperintense and T1-weighted iso-hypointense lesions, with variable contrast enhancement; areas of abnormal diffusion both in arterial and venous territories in diffusion-weighted imaging; and meningeal enhancement. On gradient echo images (GRE), the changes comprised tubular susceptibility artifacts, consistent with the “susceptibility vessel sign”, and additional variably sized/shaped intraparenchymal susceptibility artifacts. Spinal cord lesions presented as fusiform T2-weighted hyperintensities with scattered susceptibility artifacts on GRE and variable parenchymal and meningeal contrast enhancement. On histopathology, subarachnoid hemorrhages and neuroparenchymal areas of edema and necrosis, with or without hemorrhage, indicating ischemic and hemorrhagic infarctions, were found. These lesions were concurrent with severely dilated meningeal and parenchymal arteries and veins plugged by neoplastic lymphocytes and fibrin. Due to the unique angiocentric distribution of IVL, ischemic and hemorrhagic infarcts of variable chronicity affecting both the arterial and venous territories associated with thrombi formation can be detected on MRI. 相似文献
275.
276.
Julien Dupouey Benoît Faucher Sophie Edouard Hervé Richet Angeli Kodjo Michel Drancourt Bernard Davoust 《Comparative immunology, microbiology and infectious diseases》2014
Leptospirosis has been reemerging in both developed and developing countries including Europe, where, this phenomenon has notably been associated with urban transmission. However, the comprehensive data that are needed to fully understand the ongoing epidemiological trends are lacking. In this article, we report surveillance data from throughout Europe, especially in France, to have an overview of this neglected disease in temperate countries. Our results underline the important role of wild rodents as reservoir of leptospirosis, and highlight the potential danger of a reemergence of this under-reported infectious disease in European cities, associated with the important expansion of the rat population in urban areas. 相似文献
277.
Löf Magnus Barrere Julien Engman Mattias Petersson Linda K. Villalobos Adrian 《European Journal of Forest Research》2021,140(4):807-817
European Journal of Forest Research - In temperate Europe, oak-dominated forests are widespread, supporting high biodiversity and providing important ecosystem services. Insufficient natural... 相似文献