تحسين النتائح
ترتيب حسب
من
الى
الصفحة 1
الصفحة 1
Brain tumor pathology : Current diagnostic hotspots and pitfalls
Since Bailey and Cushing (1926), all brain tumor classifications have been called histogenetic. The nosographic position that the tumor types progressively acquired in the classification systems derived from the resemblance of tumor cells to those of the cytogenesis, modified whenever new information became available from different biological research fields and especially from molecular genetics. Classically, on the basis of the rough correspondence between the mature/immature aspect of tumor cells and the benign/malignant biological behavior of the tumors, the histological labels contained a prognostic significance. The supposed origin of the tumors was thus a factor for prognosis. Later on, with the concept of anaplasia (Cox, 1933; Kernohan et al., 1949) new criteria were introduced for establishing the malignancy grades of tumors. Immunohistochemistry and later molecular genetics further refined the prognostic diagnoses, substantially increasing the opportunities to recognize the cell origin of tumors, beside revealing the pathogenetic mechanisms. Prognoses became more accurate, as required by the greater and more targeted possibilities of therapy.
Arthropod Diversity and Conservation
Despite their enormous bulk and complexity of architecture, plants make up only around a quarter of a million of the 8 million or so species on Earth. The major components of biodiversity, instead, are the smaller, largely unseen, silent majority of invertebrates – most of which are arthropods. Vertebrates, a mere blip on the biotic horizon, are elevated in importance in the bigger scheme of things only by the human psyche. This collection of more than 30 peer-reviewed papers focuses on the diversity and conservation of arthropods, whose species inhabit virtually every recess and plane – and feature somewhere in virtually every food web – on the planet. Highlighting issues ranging from large-scale disturbance to local management, and from spatial heterogeneity to temporal patterns, these papers reflect some of the most exciting new research taking place today – and in some of the most biodiverse corners of the planet.
