Search results for " dose"

Effects of temperature on the acute toxicity of heavy metals (Cr, Cd, and Hg) to the freshwater crayfish, Procambarus clarkii (Girard).

1987

Chromium, an essential trace element for humans and animals is involved in normal carbohydrate metabolism; however, it is toxic at high concentrations. There is no evidence that cadmium and mercury are biologically essential but their toxicity for organisms is well known. Both cause toxic effects at low concentrations to most organisms, especially in combination with other environmental variables such as temperature. Lake Albufera and the surrounding rice field waters are subjected to very heavy loads of sewage and toxic industrial residues (including heavy metals) from the many urban and waste waters in this area. In 1978, the American red crayfish Procambarus clarkii appeared in lake Albu…

The role of cefditoren in the treatment of lower community-acquired respiratory tract infections (LRTIs): from bacterial eradication to reduced lung …

2014

Lower respiratory tract infections (LRTIs), including pneumonia and acute exacerbations of Chronic Obstructive Pulmonary Disease (COPD), are among the most common diagnoses in both outpatient and inpatient settings. Due to the burden of LRTIs healthcare providers must adopt practices focused on improving outcomes with the aim to reduce treatment failure and antibiotic resistances. Moreover, the role of acute and chronic infection in the pathogenesis of COPD has received considerable attention, since chronic infection can contribute to airways inflammation and COPD progression. This review discusses the role of cefditoren for the treatment of LRTIs, compared with the definition of "appropria…

Salbutamol Transport and Deposition in the Upper and Lower Airway with Different Devices in Cats: A Computational Fluid Dynamics Approach

2021

Simple Summary Administration of inhaled salbutamol via metered-dose inhalers can effectively treat bronchoconstriction. Different devices are used for the delivery of this drug in cats, either in the hospital or at home, for long-term treatment. Effective drug administration may depend on the drug delivery device as well as patient cooperation. By using non-invasive computational fluid dynamics techniques, the impact of these devices on the deposition and transport of salbutamol particles in the cat airways was simulated and assessed. The results confirm a variable drug distribution depending on the device used. The percentage of particles reaching the lung was reduced when using spacers a…

Finding the right dose of fulvestrant in breast cancer

2012

Fulvestrant is a selective estrogen receptor downregulator, behaving as a complete antagonist. It was initially approved, at a dose of 250 mg, to treat hormone dependant breast cancer in second line setting. However, a series of pharmacological and pre-clinical studies have suggested that a higher dose of 500 mg may be more effective. The present work summarizes and discusses clinical trials that have aimed to test the benefits of administering fulvestrant at a higher dose. The data support the use of a higher, and more possibly, effective dose of the agent.

Mycophenolate mofetil plus low-dose calcineurin inhibitor for renal dysfunction in liver transplant: A 24-month controlled clinical trial

2007

SU-E-T-176: Commissiong and Initial Clinical Experience with Dosimetry Check, a Commercial Software for in Vivo Volumetric Dosimetry

2013

Purpose: The aim of this work is to study the differences of reference point doses between the commercial EPID based dosimetry software Dosimetry Check (DC) and TPS to establish an accuracy level of the system, to evaluate its use in clinical routine and to obtain results for the first patients. Methods: We used DC v.3.8 (Math Resolutions), two Varian Clinac iX accelerators equipped with EPID aS1000 and Eclipse v.10.0 with AAA algorithm. Several plans with and without air gap were generated over the phantoms: MP1 Water Tank and Solid Octavius 4D (PTW). 5 head and neck, 3 lung and 4 prostate cases were selected for clinical evaluation. We compared the calculated dose at the isocenter and in …

Toxic Proteins and Peptides

1994

Many animals produce poisonous substances which, even at a relatively low dose, are deleterious or lethal to other organisms, including man. They may serve on the one hand to disable or kill prey, or on the other hand as a protection or defence against predators. These substances are mostly produced by special glands, and both poison reservoirs and specialized structures for delivering the secretion, e.g. stings or modified mouthparts or fangs, are usually also present. In accordance with the aims of this book, we will deal with the comparative biochemistry of the animal toxins as natural products with special structures and functions; a discussion of the mechanisms of their pharmacological…

Evaluation of lens absorbed dose with Cone Beam IGRT procedures

2015

The purpose of this work is to evaluate the absorbed dose to the eye lenses due to the cone beam computed tomography (CBCT) system used to accurately position the patient during head-and-neck image guided procedures. The on-board imaging (OBI) systems (v.1.5) of Clinac iX and TrueBeam (Varian) accelerators were used to evaluate the imparted dose to the eye lenses and some additional points of the head. All CBCT scans were acquired with the Standard-Dose Head protocol from Varian. Doses were measured using thermoluminescence dosimeters (TLDs) placed in an anthropomorphic phantom. TLDs were calibrated at the beam quality used to reduce their energy dependence. Average dose to the lens due to …

Radiation dose in non-dental cone beam CT applications: a systematic review.

2018

Background: Radiation-induced health risks are broadly questioned in the literature. As cone beam computed tomography (CBCT) is increasingly used in non-dental examinations, its effective dose needs to be known. This study aimed to review the published evidence on effective dose of non-dental CBCT for diagnostic use by focusing on dosimetry system used to estimate dose. Materials and methods: A systematic review of the literature was performed on 12 November 2017. All the literature up to this date was included. The PubMed and web of science databases were searched. Studies were screened for inclusion based on defined inclusion and exclusion criteria according to the preferred reporting ite…

Variabilidad en la utilización de antihipertensivos entre las zonas básicas de salud de la Comunidad Valenciana

2010

ResumenObjetivosEstimar el consumo de cinco subgrupos terapéuticos empleados en el tratamiento de la hipertensión arterial en las zonas básicas de salud (ZBS) de la Comunidad Valenciana, y analizar sus variaciones.MétodosEstudio ecológico, descriptivo, del consumo de antihipertensivos en las ZBS de la Comunidad Valenciana en el año 2005, seguido de análisis de la variabilidad observada. Se estudiaron las 239 ZBS existentes mediante un análisis descriptivo de consumo (dosis diarias definidas [DDD] por 1.000 habitantes y día en pensionistas [DDD/1.000p/día] o activos [DDD/1.000a/día]) y razones estandarizadas de utilización. Para el análisis de la variabilidad se utilizaron los estadísticos d…