Assessment of body position to quantify its effect on nocturnal blood pressure under ambulatory conditions.

Background: Nocturnal blood pressure readings may be influenced by body position because of variation in the vertical distance between heart and cuff level.

Objectives: To quantify the effect of body position on nocturnal blood pressure and to assess whether this effect influences the reproducibility of nocturnal blood pressure.

Patients And Methods: In 16 individuals (three normotensive and 13 hypertensive) 24 h ambulatory measurement of blood pressure and body position was performed twice, separated by an interval of 2-6 weeks.

Evaluation of techniques for the presentation of laboratory data: support of pattern recognition.

Two tabular and two graphical techniques for the presentation of laboratory test results were compared in a reaction-time experiment with 22 volunteers. The experimental setup was designed to determine whether one or more of the presentation techniques facilitated the recognition of four predefined combinations of abnormal test results. Using a conventional, tabular presentation technique as a reference, faster median response times were obtained with each of the other three presentation techniques, irrespective of pattern.

A re-appraisal of the tri-axial chart for monitoring arterial acid-base values.

Objective: To demonstrate the practicability of a tri-axial chart for the graphical and quantitative monitoring of arterial pH, arterial carbon dioxide partial pressure (PaCO2) and actual arterial bicarbonate-ion concentration (a[HCO3-]) in intensive care patients.

Design: Case report.

Setting: A general intensive care unit (ICU).

Texture analysis in radiographs: the influence of modulation transfer function and noise on the discriminative ability of texture features.

Tissue structures, represented by textures in radiographs, can be quantified using texture analysis methods. Different texture analysis methods have been used to discriminate between different aspects of various diseases in primarily x rays of chest, bone, and breasts. However, most of these methods have not specifically been developed for use on radiographs.

New developments and applications in quantitative electron spectroscopic imaging of iron in human liver biopsies.

Reliable iron concentration data can be obtained by quantitative analyses of image sequences, acquired by electron spectroscopic imaging. A number of requirements are formulated for the successful application of this recently developed in situ quantitative type of analysis. A demonstration of the procedures is given.