Search results for "evaluation studies"
showing 10 items of 112 documents
Monte Carlo calculation of dose rate distributions around 192Ir wires.
1997
Monte Carlo calculations of absolute dose rate in liquid water are presented in the form of away-along tables for 1 and 5 cm 192 Ir wires of 0.3 mm diameter. Simulated absolute dose rate values can be used as benchmark data to verify the calculation results of treatment planning systems or directly as input data for treatment planning. Best fit value of attenuation coefficient suitable for use in Sievert-integrals-type calculations has been derived based on Monte Carlo calculation results. For the treatment planning systems that are based on TG43 formalism we have also calculated the required dosimetry parameters.
Mediastinal lymph node staging with transesophageal echography in cancer of the lung.
1990
Transesophageal echography (TEE) was used prospectively to study mediastinal lymph node enlargement in 23 patients with cancer of the lung. The findings were validated blindly by comparison with computed tomography (CT, n = 23) and pathological N classification after curative surgery (n = 9). Lymph nodes larger than 1 cm were defined as pathologically enlarged. In the upper mediastinum, 22% (8 vs 36), in the lower mediastinum including the subaortic region 112% (37 vs 33) and in the hilar region 67% (6 vs 9) of enlarged lymph nodes diagnosed by CT were detected by TEE. A pathological study in 9 patients demonstrated true positive findings in 2 vs 1, true negatives in 4 vs 5, false positives…
Long-term volume-targeted pressure-controlled ventilation: sense or nonsense?
2017
The technology underlying the development of novel ventilatory modes for long-term noninvasive ventilation of patients with chronic hypercapnia is continuously evolving. Volume-targeted pressure-controlled ventilation is a hybrid ventilation mode designed to combine the advantages of conventional ventilation modes, while avoiding their drawbacks. However, manufacturers have created different names and have patented algorithms and set-up variables, which can result in confusion for physicians and respiratory therapists. In addition, clear evidence for the superiority of this novel mode has not yet been established. These factors have most likely hindered more widespread use of this mode in c…
Laser Welding - Suitable for Vascular Anastomosis?
1994
Carotid arteries of 21 piglets were transsected and reanastomosed either by laser welding (Neodym:YAG laser) or by conventional suture anastomosis. Histological specimens of the anastomoses obtained 2 to 32 days after the operation showed less foreign body reaction and intimal hyperplasia after laser welding than after suturing. There was, however, no significant difference when comparing occurrence of thrombosis, patency rate, or growth of the anastomosis in growing animals. Neither our study nor a review of the literature of laser-assisted vascular anastomosis in microvessels and large arteries up to 5 mm diameter could establish a definite clinical application for laser welding in vascul…
Evaluation of cut quality using the Amadeus microkeratome with different settings.
2004
Abstract Purpose: To evaluate the quality of keratectomy specimens created with the Amadeus® microkeratome (AMO) using scanning electron microscopy (SEM). Setting: Johannes Gutenberg-University Hospital, Department of Ophthalmology, Mainz, and the Department of Anatomy, Justus Liebig-University, Giessen, Germany. Methods: Corneal cuts were performed in freshly enucleated pig eyes using the Amadeus microkeratome with 9 combinations of oscillation rate and head-advance speed. For the cutting trials, oscillation rates of 8000, 13000, and 18000 rpm and head-advance speeds of 1.0, 2.5, and 4.0 mm/s were chosen. Fifty-four eyes were included, resulting in 9 groups of 6 eyes for each configuration…
Immunonephelometric determination of the apolipoprotein A-II.
1989
A fully mechanized immunonephelometric method is described for the rapid and specific determination of apolipoprotein A-II in serum. The method utilizes commercially available sheep antiserum against human apolipoprotein A-II. Nephelometry was performed with the Behring Nephelometer Analyzer (BNA). A single determination can be performed in 12 minutes, requiring 10 microliters sample volume. The measuring range is about 0.08 to 1.25 g/l apolipoprotein A-II. Precision is characterized by intra-assay coefficients of variation of 3.37%, 3.93% and 4.49% for apolipoprotein A-II concentrations of 1.22 g/l, 0.376 g/l and 0.185 g/l, and inter-assay coefficients of variation of 4.27% for an apolipop…
MR imaging of the lungs with hyperpolarized helium-3 gas transported by air.
2002
Hyperpolarized noble gas MRI shows promise in the functional imaging of the pulmonary air spaces. The production of hyperpolarized (HP) gas requires specialized laser optical pumping apparatus, which is not likely to be home built in the majority of clinical MRI radiology centres. There are two routes through which HP gas will be made available to hospitals for clinical use: either the apparatus will be installed locally at a considerable expense to the centre, or a central facility will produce the gas and then deliver it to remote MRI sites as and when required. In this study, the feasibility of transporting large quantities of HP gas for in vivo MR imaging from a remote production facili…
Evaluation of reverse transcription and polymerase chain reaction (RT/PCR) for the detection of rotaviruses: applications of the assay.
1996
Summary Our aim was to evaluate the reverse transcription and polymerase chain reaction (RT/PCR) technique for the detection of rotavirus shedding by infected children as a routine diagnostic procedure, in comparison to the enzyme-linked immunosorbent assay (ELISA), electron microscopy (EM) and polyacrylamide gel etectrophoresis (PAGE) of rotavirus double stranded RNA. Two-hundred and twenty stool specimens were collected from infants and young children with diarrhoea, and 10–20% faecal suspensions were made. Several methods of rotavirus dsRNA extraction were assayed. Electrophoretic analysis of viral RNA was carried out on 10% polyacrylamide gols followed by silver staining. RT/PCR was per…
Microbial evaluation of Spanish potato omelette and cooked meat samples in University restaurants.
2000
The focus of this study was to evaluate the microbial quality of Spanish potato omelette and cooked meat samples including pork loin, chicken croquettes, long pork sausage, chicken breast, and meatballs from University restaurants. Microbiological analyses of Spanish potato omelette and cooked meat samples resulted in aerobic plate counts from1.00 to 2.90 and from1.00 to 6.04 log10 CFU g(-1), respectively. Total coliforms ranged from3 to 43 most probable number (MPN) g(-1) and from3 to2,400 MPN g(-1) for Spanish potato omelette and meat products, respectively. Escherichia coli, coagulase-positive staphylococci, and Lancefield group-D streptococci were detected in 1.7%, 3.5%, and 12.9% of Sp…
Application of DNA techniques for identification using human dental pulp as a source of DNA
1992
Dental pulp tissue could be obtained in most cases from materials obtained under experimental conditions and from forensic casework (air accidents, burned and putrefied bodies). Teeth extracted during dental treatment (n = 30) were stored for 6 weeks and 4 years at room temperature. In addition teeth (n = 10) extracted from jaw fragments that had been stored for 15 years at room temperature, and teeth extracted post mortem from actual identification cases (n = 8) were investigated. Following extraction from dental pulp tissue the DNA concentration was measured by fluorometry. The amount of DNA obtained from the dental pulp tissue of a single tooth varied from 6 micrograms to 50 micrograms D…