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Biomedical subjects

W Rank

Publications and source records attributed to W Rank.

2 recordsLinked to original sources

A new coaxial needle for pre-operative localization of breast abnormalities.

A new coaxial needle, containing a retractable anchoring wire with a helical tip, has been developed for purposes of mammographic and sonographic localization of non-palpable suspicious breast abnormalities before surgical excision. The helically shaped tip provides the needle with a number of potential advantages over other currently available localization needles. During in vitro comparisons with other needles quantitative and qualitative evidence was obtained to suggest that the new needle can be expected to have improved anchoring capability, be deflected less by tough fibrous tissue interfaces and be more visible sonographically. The anchoring wire can also be retracted and repositioned. Preliminary clinical experience with the needle was consistent with these expectations.

Animals

A frequency-time domain signal processing system.

A digital signal processing system for time series analysis with two modes of usage--the first a rapid, hands-on exploratory method, and the second an automatic, printed, labeled graphic output method--is described. The system utilizes a Time Data 1923C system with integral PDP-11 minicomputer, and a console. Major error problems have been contained and a large-volume graphic analysis capability has been developed. Applications include (a) transpulmonary pressure-pulse relationships, (b) elucidation of the multiphasic nature of pulmonary-vein/left-atrial-pressure pulse phenomena, (c) suggestive value of transfer function phenomena as a tool to demonstrate the effect of various loading and ischemic phenomena on the left ventricle, and (d) teaching-demonstration of the techniques of digital signal processing.

Analog-Digital Conversion