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In this study, we evaluated by the RAPD technique the genetic diversity of 42 individual Vaccinium myrtillus L. plant samples, collected from different locations of Tuscan Apennines (Italy), which represent the southernmost growing latitude of this plant. Total polyphenols, total anthocyanins and radical scavenging activity were also determined in two successive harvesting years on bilberry samples obtained from the same individuals characterized by molecular analysis. The RAPD analysis indicated a highly prevalent gamic propagation of bilberry in the investigated area, and, in accordance with genetic findings elsewhere reported for populations of Central and Northern Europe, suggested the presence, from North-to-South Europe, of a clonal-to-gamic genetic gradient of the propagation strategy. In the context of a quite homogeneous panorama of biochemical data, significant variations were occasionally evidenced by comparing closely-located individuals. We tentatively attributed such variations mainly to genetics, due to the very close location of biomes exhibiting different biochemical attributes. However, molecular clustering by RAPD did not show any relationship with biochemical diversity. Strong variations of climatic conditions were probable responsible of the remarkable variability of the investigated biochemical parameters in the two harvesting years.  相似文献   
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Canine meningiomas are currently graded using the human grading system. Recently published guidelines have adapted the human grading system for use in dogs. The goal of this study was to validate the new guidelines for canine meningiomas. To evaluate the inter-observer agreement, 5 veterinary surgical pathologists graded 158 canine meningiomas following the human grading system alone or with the new guidelines. The inter-observer agreement for histologic grade and each of the grading criteria (mitotic grade, invasion, spontaneous necrosis, macronucleoli, small cells, hypercellularity, pattern loss and anaplasia) was evaluated using the Fleiss kappa index. The diagnostic accuracy (sensitivity and specificity) was assessed by comparing the diagnoses obtained with the 2 grading systems with a consensus grade (considered the reference classification). The consensus histologic grade was obtained by agreement between 4 experienced veterinary neuropathologists following the guidelines. Compared with the human grading alone, the canine-specific guidelines increased the inter-observer agreement for: histologic grade (κ = 0.52); invasion (κ = 0.67); necrosis (κ = 0.62); small cells (κ = 0.36); pattern loss (κ = 0.49) and anaplasia (κ = 0.55). Mitotic grade agreement remained substantial (κ = 0.63). The guidelines improved the sensitivity in identifying grade 1 (95.6%) and the specificity in identifying grade 2 (96.2%) meningiomas. In conclusion, the new grading guidelines for canine meningiomas are associated with an overall improvement in the inter-observer agreement and higher diagnostic accuracy in diagnosing grade 1 and grade 2 meningiomas.  相似文献   
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