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Biomedical subjects

A Northeved

Publications and source records attributed to A Northeved.

At least 19 recordsLinked to original sources
PubMed1979

Direct ophthalmoscopy with simultaneous colour television transmission.

The authors have developed a direct ophthalmoscope with simultaneous television transmission. The ophthalmoscope is used clinically for student as well as postgraduate teaching and for intercollegial discussion of retinal changes which give rise to differential diagnostic difficulties.

Diagnosis, Differential↗
PubMed1977

An ultrasonic multitransducer scanner for real-time heart imaging.

An ultrasonic multitransducer scanner has been developed. It works in combination with a conventional echocardiograph and is capable of instant dynamic cross-sectional imaging of the heart. A 10 cm wide area is scanned by 50 parallel sound beams, spaced 2 mm apart, at a frame rate of 36 per second. The equipment is described and preliminary clinical experience is reported. The scanner has been used for routine heart examinations and for obstetrical and abdominal scanning as well.

Echocardiography↗
PubMed1975

Ultrasonic identification and examination of fetal heart structures.

Ultrasonic studies were performed on normal fetuses ranging from 36 to 40 weeks gestational age in an attempt to visualize anatomical details of the fetal heart. We were able to visualize cardiac structures hitherto thought to be unidentifiable. Two-dimensional B-scan exposures of sections showed transverse and longitudinal sections of the fetal heart, including the cardiac septa and inlet and outlet sites of the large vessels. To attempt to elucidate the dynamics of the fetal heart, the motility patterns of the cardiac structures were examined by time-motion mode scanning and the patterns obtained were compared to those observed in the postnatal heart. The reliability of the theories advanced and the further prospects are discussed.

Coronary Vessels↗
PubMed1975

Demonstration of boundary lubrication by synovial fluid.

An account is given of an oscillatory rotating friction measurement apparatus which can be used for demonstration of boundary lubrication by synovial fluid when rubber and glass are employed as rubbing surfaces. A technical description of the apparatus is given. The greatest importance is placed on getting the apparatus to demonstrate reproducible results when saline and normal bovine synovial fluid are used as lubricant. The greatest variations are caused by differences in the cleaning of the rubber and in its tension. On the basis of bovine synovial fluid from ten different hock joints investigations were made of individual variations and changes occurring during storage at 4 degrees C. The individual variations were found to be of no importance; a decrease in the lubricating effect was observed only after storage for two months. Addition of trypsin confirmed that boundary lubrication by synovial fluid can be related to the protein component. The conclusion is that the apparatus is considered suitable for clinical investigations of boundary lubrication in connection with different joint diseases.

Animals↗
PubMed1975

Measurement of the viscosity of synovial fluid.

An account is given of a viscometer which can be used for measuring the viscosity of synovial fluid when only small quantities are avaliable (0.15 ml) and taking into account the non-Newtonian character of the fluid. A technical description of the apparatus is given. A series of experiments are reported in which bovine synovial fluid was used to study whether and what changes took place in connection with storage, alterations in temperature, and post mortem. It was shown that storage at 4 degrees C for up to 2 weeks did not cause any particular changes, that alterations in temperature from room temperature to body temperature resulted in a moderate decrease in the relative viscosity, and that changes found 6 hours post mortem seemed to be insignificant. The conclusion drawn from the experiments is that the apparatus can be regarded as suitable for use in a more comprehensive study of the changes in viscosity which occur in various joint diseases.

Animals↗