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Biomedical subjects

P Baraldi

Publications and source records attributed to P Baraldi.

31 records · Page 2Linked to original sources
PubMed1986

Device for eliminating corneal light reflections during recording of lateral images with a slit lamp.

Corneal reflections produce defects in photographic sections of the lens taken with a slit-lamp biomicroscope for computerized densitometric analysis of cataract opacity. A simple and workable, adjustable antireflection device was built that can be easily adapted to photographic slit lamps, a common instrument in ophthalmology equipment. The slit lamp is a versatile tool for photographing structures in the anterior segment of the eye, particularly the lens. Corneal reflections are eliminated for angles between the light band and a photograph plane ranging from 20 degrees to 90 degrees, with the light band no greater than 0.5 mm and the corneal curvature about 7.6 to 7.9 mm. The device acts by blocking aberrant light rays from the light source that would otherwise be reflected by the mirrorlike surface of the cornea and enter the objective lens. Here we present a prototype designed for the Zeiss slit lamp.

Cornea↗
PubMed1986

Modifications of the slit lamp for digital image processing of the anterior segment of the eye.

The Zeiss slit lamp has been modified in order to extend its use to measurements of lens transparency. Two major modifications have been introduced: (1) a support for a high-sensitivity TV camera that is connected to an image processing system; (2) two potentiometers for recording electrical signals proportional to the rotation angle of the slit-supporting arm with respect to the visual axis and the slit tilting angle. As a result, the slit lamp output consists of three signals; one TV signal for the images and two analog signals for measurement of the angles. With the aid of an image-processing system connected to a minicomputer, software has been developed to enable the operator to acquire reliable digital images of the anterior segment of the eye in real time. The software provides the user with an easy-to-follow menu.

Anterior Eye Segment↗
PubMed1984

Improvements in clinical electronystagmogram analysis.

The authors apply the technique of amplitude histogram analysis to the clinical electronystagmogram (ENG). After a brief survey of the underlying concepts, some typical normal and pathological ENG records are discussed. Comparison of advantages and disadvantages reveals that the quoted technique may be suitable to be profitably introduced in clinical practice.

Electronystagmography↗
PubMed1984

Computer-assisted analyses of [14C]2-DG autoradiographs employing a general purpose image processing system.

A general purpose image processing system is described including B/W TV camera, high resolution image processor and display system (TESAK VDC 501), computer (DEC PDP 11/23), and monochrome and color monitors. Images may be acquired from a microscope equipped with a TV camera or using the TV in direct viewing; the A/D converter and the image processor provides fast (40 ms) and precise (512 X 512 data points) digitization of TV signal with a 256 gray levels maximum resolution. Computer programs have been developed in order to perform qualitative and quantitative analyses of autoradiographs obtained with the 2-DG method, which are written in FORTRAN and MACRO 11 Assembly Language. They include: (1) procedures designed to recognize errors in acquisition due to possible image shading and correct them via software; (2) routines suitable for qualitative analyses of the whole image or selected regions of it, providing the opportunity for pseudocolor coding, statistics, graphic overlays; (3) programs permitting the conversion of gray levels into metabolic rates of glucose utilization and the display of gray- or color-coded metabolic maps.

Animals↗
PubMed1983

[Blood viscosity and erythrocyte deformability in diabetic retinopathy].

The whole blood and plasma viscosity, hematocrit and plasma fibrinogen were studied in 26 diabetic patients (11 with and 15 without retinopathy) and in 25 non-diabetic control subjects. Blood viscosity, plasma viscosity and plasma fibrinogen were significantly higher in diabetics than in controls, but no significant differences were found when diabetics with retinopathy were compared to diabetics without retinopathy. The red cell deformability was significantly reduced in diabetics if compared with that of controls; the statistical significance of this reduction was confirmed only in the group of diabetics with retinopathy, but failed when the group of diabetics without retinopathy was considered.

Adult↗
PubMed1982

Sustained haemodynamic and clinical effects of captopril in long-term treatment of severe chronic congestive heart failure.

1 The angiotensin-converting-enzyme inhibitor captopril is known to produce beneficial haemodynamic effects in patients with chronic congestive heart failure. 2 Twelve patients with chronic congestive heart failure were conventionally treated with digitalis and diuretic therapy plus oral captopril (75-150 mg/day), and 14 patients were used as a control group. 3 There was no improvement in functional and haemodynamic values in the controls, but the patients treated with captopril showed a significant functional improvement (increase of exercise time and improvement in New York Heart Association functional class), a definitive decrease in systemic vascular resistance (20%), and a significant increase in the cardiac index and ejection fraction (18% and 28% respectively).

Aldosterone↗
PubMed1981

Vision in the neonate (full-term and premature): preliminary result of the application of some testing methods.

Little information is available on the functionality of the visual system in neonates. Comparison was made between neonates born at full term and prematures equated for conceptional age, using two methods of investigation: the visual evoked potential (VEP) and the "forced preferential looking" (FPL). The results obtained by the FPL method indicate a greater visual acuity in premature subjects, whereas the results obtained by the VEP method point to no significant difference in implicit time between the two groups.

Evoked Potentials↗
PubMedDate not supplied

Study of the vibrational spectrum of cuprorivaite.

In this research, after tracing a history of the pigment, the preparation and analysis of samples of Egyptian blue have been reported. The main reactions taking place during its preparation are indicated. X-ray diffractions show that, starting from mixtures of precursors with stoichiometric composition, the product is practically only cuprorivaite. The kind of flux and cristallinity of silica does not seem determining factors for the pigment formation. Infrared and Raman spectra and an assignment of the bands are reported. Impurities ascertained are discussed on the basis on the data available.

Copper↗