Search results for "valve"
showing 10 items of 576 documents
Parasites in sympatric populations of native and invasive freshwater bivalves
2021
An increasing threat to local, native freshwater mussels (Unionida)—an ecologically important but globally alarmingly declining group— is the invasion by exotic bivalves. The Enemy Release Hypothesis predicts that introduced species should benefit from enemy-mediated competition because they are less likely to be harmed by natural enemies, such as parasites, than their native competitors. We investigated within-site differences in parasitism between sympatric native (tot. five spp.) and invasive (tot. three spp.) bivalves in eight northern European waterbodies, which harboured totally 15 parasite taxa. In paired comparisons using within-site averages, the mean number of parasite species in …
Increased Parasite Abundance Associated with Reproductive Maturity of the Clam Anodonta piscinalis
1999
Several studies on vertebrates have demonstrated that reproductive activities may increase the parasite load, but this has not been shown in invertebrate hosts. We studied abundance of a potentially harmful gill parasite, the ergasilid copepod Paraergasilus rylovi, from the freshwater bivalve host Anodonta piscinalis in relation to reproductive maturity of the host in the field. Prevalence of this previously unstudied parasite varied from 90 to 100%, and the mean parasite abundance from 16.3 to 28.8 among 3 study populations. Abundance of P. rylovi increased with host size. In the maturating age groups (3-5 yr) the length-adjusted mean parasite abundance among mature, reproducing female cla…
Potential and limitation of combining terrestrial and marine growth records from Iceland
2017
Abstract Seasonally formed, perennial growth increments of various organisms may possibly contain information about past environmental changes, well before instrumental measurements occurred. Such annually resolved proxy records have been mainly obtained from terrestrial archives, with a paucity of similar data originating from marine habitats. Iceland represents ideal conditions to develop both, tree ring (dendro) and bivalve shell (sclero) chronologies from adjacent sites. Here we introduce the first network of Icelandic birch (Betula pubescens Ehrh.) and rowan (Sorbus aucuparia) dendrochronologies, as well as ocean quahog (Arctica islandica L.) sclerochronologies. In order to identify th…
Verschluß einer Gaumenspalte bei einer Patientin mit Ebstein-Anomalie unter Hochfrequenzoszillationsbeatmung
1998
Hintergrund: Es wird uber den zunachst nicht erfolgreichen Versuch der konventionellen Beatmung wahrend eines kieferchirurgischen Eingriffs bei einer Patientin mit Ebstein-Anomalie berichtet. Verminderter pulmonaler Blutflus und entsprechend verminderter linksventrikularer Auswurf fuhrten zu einer arteriellen Hypotonie mit Sauerstoffsattigungsabfall. Unter Spontanatmung normalisierte sich der kritische Zustand rasch. Operation: Der Einsatz eines Hochfrequenzoszillationsbeatmungsgerats (SensorMedics 3100A) mit gleichbleibendem mittlerem Atemwegsdruck und Vermeiden inspiratorischer Spitzendrucke ermoglichte 2 Jahre spater eine adaquate Ventilation und Oxygenierung der Patientin, so das die Op…
Spin Hanle effect in mesoscopic superconductors
2014
Under the terms of the Creative Commons Attribution License 3.0 (CC-BY).
Polyamines and microbiota in bicuspid and tricuspid aortic valve aortopathy
2019
Polyamines are small aliphatic cationic molecules synthesized via a highly regulated pathway and involved in general molecular and cellular phenomena. Both mammalian cells and microorganisms synthesize polyamines, and both sources may contribute to the presence of polyamines in the circulation. The dominant location for microorganisms within the body is the gut. Accordingly, the gut microbiota probably synthesizes most of the polyamines in the circulation in addition to those produced by the mammalian host cells. Polyamines are mandatory for cellular growth and proliferation. Established evidence suggests that the polyamine spermidine prolongs lifespan and improves cardiovascular health in …
Two-year outcomes from the MitrAl ValvE RepaIr Clinical (MAVERIC) trial: a novel percutaneous treatment of functional mitral regurgitation.
2021
AIMS We report the 2-year outcomes of the MitrAl ValvE RepaIr Clinical (MAVERIC) trial. Functional mitral regurgitation (FMR) is associated with poor outcomes for which there remains an unmet clinical need. ARTO is a transcatheter annular reduction device for the treatment of FMR and an emerging alternative for patients at high surgical risk. The MAVERIC trial was designed to evaluate the safety and performance of the ARTO system in FMR and heart failure (HF). METHODS AND RESULTS MAVERIC is an international multicentre, prospective, single arm study enrolling patients with FMR grade ≥ 2, New York Heart Association (NYHA) class ≥II symptoms despite maximal medical therapy. Patients were excl…
Role of functional mitral regurgitation in heart failure with preserved ejection fraction: an unrecognized protagonist?
2016
The Association of H1N1 Pandemic Influenza with Congenital Anomaly Prevalence in Europe
2015
BACKGROUND: In the context of the European Surveillance of Congenital Anomalies (EUROCAT) surveillance response to the 2009 influenza pandemic, we sought to establish whether there was a detectable increase of congenital anomaly prevalence among pregnancies exposed to influenza seasons in general, and whether any increase was greater during the 2009 pandemic than during other seasons.METHODS: We performed an ecologic time series analysis based on 26,967 pregnancies with nonchromosomal congenital anomaly conceived from January 2007 to March 2011, reported by 15 EUROCAT registries. Analysis was performed for EUROCAT-defined anomaly subgroups, divided by whether there was a prior hypothesis of…
What Is the Role of Minimally Invasive Mitral Valve Surgery in High-Risk Patients? A Meta-Analysis of Observational Studies
2016
Background. Minimally invasive valve surgery is related to certain better postoperative outcomes. We aimed to assess the role of minimally invasive mitral valve surgery in high-risk patients. Methods. A systematic literature review identified eight studies of which seven fulfilled criteria for metaanalysis. Outcomes for a total of 1,254 patients (731 were conventional standard sternotomy and 523 were minimally invasive mitral valve surgery) were submitted to meta-analysis using random effects modeling. Heterogeneity and subgroup analysis with quality scoring were assessed. The primary end point was early mortality. Secondary end points were intraoperative and postoperative outcomes and long…