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High field magnetic resonance imaging contributes to diagnosis of equine distal tarsus and proximal metatarsus lesions: 103 horses 下载免费PDF全文
Myra F. Barrett Kurt T. Selberg Sherry A. Johnson Jake Hersman David D. Frisbie 《Veterinary radiology & ultrasound》2018,59(5):587-596
Injury of the distal tarsus and proximal metatarsus commonly causes lameness. Magnetic resonance imaging (MRI) allows concurrent assessment of both the distal tarsal joints and suspensory ligament origin, and aids identification of lesions that may otherwise go undetected by other modalities. In this retrospective observational study, the medical records of a veterinary imaging center were searched for MRI exams of the distal tarsus and proximal metatarsus for the years 2012 through 2014. Studies for 125 limbs of 103 horses were identified and retrospectively evaluated by two board‐certified veterinary radiologists. Soft tissue and osseous changes were characterized and graded by degree of severity. The patients’ signalment, lameness severity, and results of diagnostic analgesia were recorded. Osteoarthritic changes of the distal intertarsal and tarsometatarsal joints were the most common findings. Other findings included bone marrow lesions, degenerative changes of the small cuboidal bones, subchondral cystic lesions, and intertarsal desmopathy. Suspensory ligament desmopathy was found in 53% of limbs. Fourty‐seven percent of limbs that responded to analgesia of the proximal suspensory ligament had more severe lesions in the distal tarsus. Bone marrow lesions of the third tarsal bone were the only MRI finding that correlated with grade of lameness in patients for which lameness grade was reported. The grade of lameness has a poor correlation with the severity of lesions found on MRI. The findings support the use of MRI for simultaneous evaluation of the proximal metatarsus and distal tarsus, particularly given the difficulty of lesion localization with diagnostic analgesia. 相似文献
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Allen V. Barker Touria E. Eaton Md J. Meagy Emad Jahanzad Gretchen M. Bryson 《Journal of plant nutrition》2017,40(17):2432-2439
An improvement in the mineral nutrient contents of fruits and vegetables is needed to offset reported declines in concentrations of these elements in fruits and vegetables. The declines have been associated with the high productivity of modern cultivars and to depleted soil fertility. This research addressed differences in mineral nutrient concentrations between modern F1 hybrids and heirloom cultivars of cabbage (Brassica oleraceae var. capitata L.)and among fertilization practices with conventional chemical or organic fertilizers and compost. Crop production was greater with the chemical or organic fertilizers than with the compost. Mineral nutrient composition did not vary between modern or heirloom cultivars or among fertilization regimes but varied among cultivars, suggesting that cultivar selection could lead to production of nutrient-rich cabbage. Neither mass of heads nor days to maturation of crops affected nutrient composition. 相似文献
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Huston’s Dynamic Equilibrium Hypothesis predicts that the response of biodiversity to disturbance varies with productivity.
Because disturbance is thought to break competitive advantage of dominant species in productive ecosystems, species richness
is predicted to increase with disturbance frequency in productive systems. Recovery of plant biomass following disturbance
is also predicted to be faster in productive systems. Here we provide the first test of Huston’s hypothesis in the context
of setting harvest rates in managed forests for achieving biodiversity objectives. We examined predictions relating to vegetation
and bird response to disturbance and succession in productive and less productive forests in western Oregon and Washington,
USA. We found that measurements of understory cover and shrub diversity were higher in young, productive stands than less
productive stands of similar age. Later-seral forests in productive environments (mean age = 67 years) had less variable and
more complete canopy closure than similar-age forests in less favorable settings. At the stand scale, bird abundance and richness
decreased with canopy closure in highly productive forests whereas bird abundance and richness increased with canopy closure
in less productive forests. At the landscape scale, bird abundance and richness within stands increased with increasing levels
of disturbance in the surrounding landscape within highly productive forests, whereas bird abundance and richness decreased
with increasing disturbance in the surrounding landscape within less productive forests. Our results indicate that bird response
to disturbance varies across levels of productivity and suggest that bird species abundance and associated species richness
will be maximized through relatively more frequent disturbance in highly productive systems. 相似文献
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C L Swenson J Silverman P C Stromberg S E Johnson D A Wilkie K A Eaton G J Kociba 《Journal of the American Veterinary Medical Association》1988,193(9):1089-1092
Visceral leishmaniasis was diagnosed in a 5-year-old English Foxhound born and housed in an Ohio research colony. Physical examination revealed pyrexia, hematochezia, panuveitis, splenomegaly, and lymphadenopathy. Hematologic and serum biochemical abnormalities consisted of anemia, thrombocytopenia, hypoalbuminemia, hyperglobulinemia, azotemia, and proteinuria. Postmortem examination revealed widely disseminated (spleen, bone marrow, lymph node, liver, kidney, lungs) Leishmania amastigotes within macrophages. 相似文献
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