Search results for "ECOLOGIA"
showing 10 items of 1399 documents
La hipoxia fetal valorada mediante métodos objetivos y su relación con el Factor de crecimiento del Endotelio Vascular (VEGF) en gestaciones gemelare…
2008
Introducción Para el correcto desarrollo placentario y fetal, se requieren los procesos de vasculogénesis y angiogénesis que están regulados entre otros por la familia VEGF y el Factor de crecimiento placentario (PlGF) que traducen sus señales uniendose a sus receptores transmembrana, el VEGFR1 y 2. El VEGFR1 tiene una forma soluble ( s.Flt-1) que actúa como un inhibidor del VEGF y del PlGF . El VEGF-A es el principal regulador de la angiogénesis siendo el VEGF-121 y VEGF-165 las 2 isoformas más predominantes e importantes, y estando su expresión regulada por la hipoxia. La hipoxia debida a insuficiencia placentaria se observa en gestaciones gemelares con discrepancia ponderal entre los fet…
Ciclos de fecundación in vitro y maduración final con agonista GNRH: Explorando dosis bajas de HCG para soporte de fase lutea
2010
La hormona gonadotropina coriónica humana (hCG) se emplea de forma rutinaria para inducir la maduración final ovocitaria en ciclos de fecundación in vitro (FIV). Sin embargo, su utilización está relacionada con la aparición del Síndrome de Hiperestimulación Ovárica (SHO), especialmente cuando ciertos factores de riesgo están presentes, principalmente la presencia de un número elevado de folículos. Este riesgo puede ser drásticamente disminuido sustituyendo la hCG por un agonista GnRH como inductor de la maduración final en ciclos FIV con antagonistas GnRH. Aunque, este uso se asocia a una alta tasa de aborto temprano ocasionada por una fase lútea deficiente. La función del cuerpo lúteo se v…
Deep-Sea Bioluminescence Blooms after Dense Water Formation at the Ocean Surface
2013
The deep ocean is the largest and least known ecosystem on Earth. It hosts numerous pelagic organisms, most of which are able to emit light. Here we present a unique data set consisting of a 2.5-year long record of light emission by deep-sea pelagic organisms, measured from December 2007 to June 2010 at the ANTARES underwater neutrino telescope in the deep NW Mediterranean Sea, jointly with synchronous hydrological records. This is the longest continuous time-series of deep-sea bioluminescence ever recorded. Our record reveals several weeks long, seasonal bioluminescence blooms with light intensity up to two orders of magnitude higher than background values, which correlate to changes in th…
Globorotalia truncatulinoides in the Mediterranean Basin during the Middle–Late Holocene: Bio-Chronological and Oceanographic Indicator
2022
The planktonic foraminiferal species Globorotalia truncatulinoides is widely used as a biostratigraphic proxy for the Quaternary in the Mediterranean region. High-resolution quantitative studies performed on sediment cores collected in the central and western Mediterranean Sea evidence a significant abundance of G. truncatulinoides during the Middle Holocene. The robust chronological frame allows us to date this bio-event to 4.8–4.4 ka Before Present (BP), very close to the base of the Meghalayan stage (4.2 ka BP). As a consequence, we propose that G. truncatulinoides can be considered a potential marker for the Middle–Late Holocene chronological subdivision. G. truncatulinoides is a deep-d…
LA COLLEZIONE DI AMMONOIDI TRIASSICI G.G. GEMMELLARO. REVISIONE SISTEMATICA ED IMPORTANZA PALEOBIOGEOGRAFICA
2011
Attuali orientamenti nella diagnosi e nel trattamento delle aderenze placentari patologiche: la nostra esperienza
2010
The abnormal adherence of the placenta is a disease characterized by an anomalous miometrial infiltration of Chorionic villi. This event blocks the regular detachment of placenta in post partum and sometimes a severe bleeding that causes the urgency of a caesarean section. In the past years the incidence of this pathology has increased to about 1 in 500/600 deliveries. The cause of abnormal adherence of placenta is unknown but there are some risk factors such as prior caesarean sections, women older than 35 years of age and placenta previa. The early diagnosis is very important and it can be done by Eco-Color-doppler (eventually associated with 3d technique) and Magnetic Resonance. Objectiv…
Carbonate/evaporitic sedimentation during the Messinian salinity crisis in active accretionary wedge basins of the northern Calabria, southern Italy
2020
Abstract This work deals with Messinian deposits belonging to the Neogene infill of the Rossano and Belvedere Basins, respectively developed along the fore-arc and the back-arc areas of the north Calabria accretionary wedge. The main goal is to characterize the carbonate and evaporitic sedimentation during the Messinian Salinity Crisis, in the general framework of the basin architecture and the interplay between eustatic vs tectonic controlled sea-level variations. Fieldwork integrated with seismic lines and well logs interpretations led to the revision of the general stratigraphy of the basins and the proposal of a new sequential stratigraphic model driven by cyclic sea-level variations. E…
Effect of Multiple Stressors on marine organism predicted and quantified through bioenergetic mechanistic models
Anthropogenic pressure on coastal ecosystems is vast and diverse, simultaneous impacts such as pollution, eutrophication and fishing pressure nowadays add up and interact with the effects of climate change (e.g., global warming, acidification and sea level rise). The magnitude of these effects on marine species and their replies can vary and the possible changes can depend on: i) species life-histories (LH) traits, ii) local environmental conditions and iii) contextual presence of more than one anthropogenic related stressor. The study of a single anthropogenic disturbance or Climate Change-derived alteration on multi-level ecological responses is misleading and generates unrealistic conclu…
Can We Define the Risk of Lymph Node Metastasis in Early-Stage Cervical Cancer Patients? A Large-Scale, Retrospective Study
2017
BACKGROUND: Sentinel lymph node (SLN) biopsy has emerged as one of the most appreciated techniques for reducing the rate of complete lymph node dissection (LND) performed in patients with early-stage cervical cancer (ECC). However, its performances are still a matter of debate and, to improve them, international guidelines recommend performing at least unilateral LND in case of SLN mapping. In a prior study, we identified a group of patients without evidence of lymph node metastasis (LNM). Our objective is to define a precise risk of LNM for each ECC patient in order to significantly tailor surgery for ECC. METHODS: Clinical and pathological data of ECC patients were retrospectively collect…
Does the level of serum antimüllerian hormone predict ovulatory function in women with polycystic ovary syndrome with aging?
2012
Abstract OBJECTIVE: To determine possible prediction of regular menses with aging in anovulatory women with polycystic ovary syndrome (PCOS). DESIGN: Cohort. SETTING: Academic practice. PATIENT(S): A total of 54 anovulatory women with PCOS and 28 age- and weight-matched control subjects. INTERVENTION(S): Blood and ovarian ultrasound at baseline and after 5 years. MAJOR OUTCOME MEASURE(S): Serum antimüllerian hormone (AMH), gonadotropins, androgens, insulin sensitivity, and ovarian ultrasound. RESULT(S): After 5 years, there was a significant decrease in AMH in women with PCOS and control subjects (10 of 54 anovulatory women became ovulatory after 5 years). There was a significant negative c…