Search results for "H2"

Clinic modelling randomised trials (CMRT's) in animals as a new intermediate between biological experiments and randomised clinical trials: applicati…

1998

Negative Effect of Ranitidine on The Results of Urea Breath Test for The Diagnosis of Helicobacter Pylori

2001

In analogy with proton pump inhibitors, H2-antagonists may also be responsible for false-negative results on urea breath test for the detection of Helicobacter pylori. In this study we assessed the frequency and duration of false-negative urea breath tests in patients given different doses of ranitidine.A total of 120 consecutive dyspeptic patients infected with H. pylori on the basis of concomitant positive results of CLO-test, histology and urea breath test were recruited for this prospective, open, parallel-group study performed in an urban university gastroenterological clinic. They were randomized to receive an acute treatment with either ranitidine 300 mg once a day in the evening, ra…

Histamine release in mesenteric traction syndrome during abdominal aortic aneurysm surgery: prophylaxis with H1 and H2 antihistamines

2002

Objective and design: Mesenteric traction syndrome is described as sudden tachycardia, hypotension and flush. Among other etiological factors eventeration or mesenteric traction of the small intestine may cause histamine release from mesenteric mast cells. We hypothesized that mesenteric traction syndrome may be positively influenced by prophylactic antihistamine administration.¶Methods: Male patients (n = 17, ASA groups III-IV, 48–78 years old) were investigated in a randomised double blind study during elective abdominal aortic aneurysm (AAA) repair. Eight patients had pre-anaesthetic prophylaxis with dimetindene (H1-receptor antagonist) plus cimetidine (H2-receptor antagonist), 9 patient…

The Shwartzman reaction repealed

2007

The article, “ -Galactosylceramide induces protection against lipopolysaccharide-induced shock” (doi:10.1189/jlb.0506298), was selected as a Pivotal Advance because the results suggest that -galactosylceramide ( GalCer), a glycolipid isolated from marine sponges, can protect against the complete morbidity and mortality characterisitic of endotoxin shock by inducing NKT cells to produce TH2 cytokines.

Gas Barrier, Rheological and Mechanical Properties of Immiscible Natural Rubber/Acrylonitrile Butadiene Rubber/Organoclay (NR/NBR/Organoclay) Blend N…

2020

In this paper, gas permeability studies were performed on materials based on natural rubber/acrylonitrile butadiene rubber blends and nanoclay incorporated blend systems. The properties of natural rubber (NR)/nitrile rubber (NBR)/nanoclay nanocomposites, with a particular focus on gas permeability, are presented. The measurements of the barrier properties were assessed using two different gases—O2 and CO2—by taking in account the blend composition, the filler loading and the nature of the gas molecules. The obtained data showed that the permeability of gas transport was strongly affected by: (i) the blend composition—it was observed that the increase in acrylonitrile butadiene rubber compon…

“Compatibilization” through Elongational Flow Processing of LDPE/PA6 Blends

2018

Polyamide/polyolefin blends have gained attention from the academia and the industry for several years. However, in order to optimize their properties, some drawbacks such as chemical incompatibility must be adequately overcome. This can be done by adding suitable compatibilizers. On the other hand, it is less known that suitable processing techniques may also lead to significant results. In a previous work on a low-density polyethylene/polyamide 6 (LDPE/PA6) blend, we found that the orientation due to elongational flow processing conditions could lead to an unexpected brittle&ndash

On the Phase Separation in n-Type Thermoelectric Half-Heusler Materials

2018

Half-Heusler compounds have been in focus as potential materials for thermoelectric energy conversion in the mid-temperature range, e.g., as in automotive or industrial waste heat recovery, for more than ten years now. Because of their mechanical and thermal stability, these compounds are advantageous for common thermoelectric materials such as Bi 2 Te 3 , SiGe, clathrates or filled skutterudites. A further advantage lies in the tunability of Heusler compounds, allowing one to avoid expensive and toxic elements. Half-Heusler compounds usually exhibit a high electrical conductivity σ , resulting in high power factors. The main drawback of half-Heusler compounds is their high lattice th…

Deformation and failure of MXene nanosheets

2020

This work is aimed at the development of finite element models and prediction of the mechanical behavior of MXene nanosheets. Using LS-Dyna Explicit software, a finite element model was designed to simulate the nanoindentation process of a two-dimensional MXene Ti3C2Tz monolayer flake and to validate the material model. For the evaluation of the adhesive strength of the free-standing Ti3C2Tz-based film, the model comprised single-layered MXene nanosheets with a specific number of individual flakes, and the reverse engineering method with a curve fitting approach was used. The interlaminar shear strength, in-plane stiffness, and shear energy release rate of MXene film were predicted using th…

Influence of Glass Additions on Illitic Clay Ceramics

2020

A mixture of an illitic clay and waste glass was prepared and studied during the sintering process. The illitic clay, from the Liepa deposit (Latvia), and green glass waste (GW) were disintegrated to obtain a homogeneous mixture. The addition of disintegrated GW (5&ndash

Characterization of Different Cable Ferrite Materials to Reduce the Electromagnetic Noise in the 2–150 kHz Frequency Range

2018

The gap of standardization for conducted and field coupled electromagnetic interferences (EMI) in the 2–150 kHz frequency range can lead to Electromagnetic Compatibility (EMC) problems. This is caused by power systems such as Pulse Width Modulation (PWM) controlled rectifiers, photovoltaic inverters or charging battery units in electric vehicles. This is a very important frequency spectral due to interferences generated in a wide range of devices and, specifically, communication problems in the new technologies and devices incorporated to the traditional grid to convert it into a Smart Grid. Consequently, it is necessary to provide new solutions to attenuate this kind of interference, which…