Search results for "ISTHMUS"
showing 4 items of 4 documents
Parallel diversifications of Cremastosperma and mosannona (annonaceae), tropical rainforest trees tracking neogene upheaval of South America
2018
Much of the immense present day biological diversity of Neotropical rainforests originated from the Miocene onwards, a period of geological and ecological upheaval in South America. We assess the impact of the Andean orogeny, drainage of Lake Pebas and closure of the Panama isthmus on two clades of tropical trees ( Cremastosperma , ca 31 spp.; and Mosannona , ca 14 spp.; both Annonaceae). Phylogenetic inference revealed similar patterns of geographically restricted clades and molecular dating showed diversifications in the different areas occurred in parallel, with timing consistent with Andean vicariance and Central American geodispersal. Ecological niche modelling approaches show phyloge…
Gold vs. platinum-iridium tip catheter for cavotricuspid isthmus ablation: the AURUM 8 study
2010
Aims Gold electrodes have the theoretical advantage of creating bigger lesions than platinum–iridium (Pt–Ir) electrodes. We performed a prospective randomized study to compare the clinical efficacy of standard 8 mm Pt–Ir tip catheter (control) and 8 mm gold-tip catheters in the ablation of the cavotricuspid isthmus (CTI)-dependent atrial flutter. Methods and results A total of 463 patients undergoing CTI ablation in 19 clinical centres were randomized to receive the treatment by gold-tip or control catheter. The primary endpoint was cumulative radiofrequency (RF) application duration until achieving bidirectional CTI block. It did not differ significantly for the two catheters. The gold-tip…
Long and fluctuating bone fragments in uterine isthmus: a curious feature of true osseous metaplasia.
2013
Osseous metaplasia in the uterine cavity is a rare phenomenon arising from an unusual transformation of non-osseous connective tissue into mature bone. It is unclear how this alteration occurs and it has no single clinical manifestation. We report a case of asymptomatic endometrial osseous metaplasia of the isthmus with a singular picture: numerous long, floating bone-like structures in the cavity. The lesion was treated by operative hysteroscopy. Histological findings described a rare picture of true osseous metaplasia with the extraordinary presence of cells referable to areas of hematopoietic tissue in the cavities of trabecular bone. Physicians should be more informed and alert regardin…
Third canal in the mesial root of permanent mandibular first molars: Review of the literature and presentation of 3 clinical reports and 2 in vitro s…
2007
Introduction. Systematic anatomical studies corroborate the anatomical complexity of the root canal system. Deviations from the norm such as multiple orifices, apical deltas, accessory canals and other variations are frequent. Objectives. To present clinical reports of mandibular molars with three canals in the mesial root and two in vitro studies of the morphology of these canals, together with a review of the literature. Materials and Methods. Three clinical reports are presented of mandibular molars where three canals in the mesial roots were treated endodontically. Two in vitro studies were performed, one using computerized tomography and the other with scanning electron microscopy, to …