ISSN:0363-8855    

出版商:OVID    

年代:1984

数据来源: OVID

摘要:

The increasing cost and complexity of state-of-the-art radiological equipment, and the need for more comprehensive safety and performance assurance, have increased maintenance expenditures to a level where they have become one of the largest operating expenses of radiology departments. To cope with this ever increasing expenditure, a comprehensive in-house maintenance program was implemented in our institution. This program properly balanced the capability of the radiology department's in-house technical personnel with support provided by equipment manufacturers' service organizations. Quality assurance activities are also included as an integral part of the entire program. Since the implementation of the program, an average 40% reduction in the annual maintenance expenditure has been observed.

ISSN:0363-8855    

出版商:OVID    

年代:1984

数据来源: OVID

摘要:

It is often difficult to differentiatepremature ventricular contractions(PVCs) frompremature atrial contractions(PACs) with aberrant conduction by means of surface electrocardiograms. This differentiation is of considerable importance, as the treatment for the two entities differs. Premature beats commonly occur following open-heart surgery. Often during open-heart surgery, the atrial and ventricular pacing wires are inserted and brought to the surface. It is then possible to record the epicardial atrial and ventricular electrograms from these pacing wires. In this paper, the differentiation between PVC and PAC with aberrant conduction is performed using a microcomputer. To minimize the system's cost, the Radio Shack TRS-80 Color Computer, a commercially available personal microcomputer, was chosen as the basis for the monitoring system. After filtering and amplification, the ECG is digitized and analyzed. Once atrial or ventricular activity has been established, an algorithm is used to determine whether the heartbeat was a normal beat, a PAC, or a PVC. This algorithm is based upon the fact that normal beats, PACs, and PVCs have the P wave and QRS complex in a known sequence, with an identifiable time between beats. The occurances of PACs and PVCs are monitored and recorded for future analysis.

ISSN:0363-8855    

出版商:OVID    

年代:1984

数据来源: OVID

ISSN:0363-8855    

出版商:OVID    

年代:1984

数据来源: OVID

ISSN:0363-8855    

出版商:OVID    

年代:1984

数据来源: OVID

摘要:

Computerized decision making aids have been developed for use in certain medical specialties over the last decade. These programs are designed to give expert-level advice within their limited domains. Two major components are required in the design of these systems: development of software and development of a knowledge base to handle the specific medical application. The advantage of the knowledge-based approach is that the application can be changed by replacement of the knowledge base, without requiring changes to the software. In this paper,EMERGE, a medical decision making system, originally developed for analysis of chest pain in the emergency room environment, is described. EMERGE uses production rules for representation of its knowledge base. The method by which this system can accommodate new rule bases for other applications is emphasized, as well as the transportability of the system.

ISSN:0363-8855    

出版商:OVID    

年代:1984

数据来源: OVID

摘要:

This paper reviews the development of the Kock procedure for continent ileostomy. Several problems are encountered in this procedure; primarily relating to 1) construction of the ileal reservoir and 2) construction of the “valve” or continence mechanism. Alternative approaches to each of these areas are compared. Techniques for creation of the ileal reservoir have improved to the stage where advances come slowly. In the area of the continence mechanism, numerous alternatives continue to be evaluated. In general, the procedure is evolving. The use of biomaterials to reinforce the “valve” is on the rise. Advantages and disadvantages of alternative technological approaches are compared.

ISSN:0363-8855    

出版商:OVID    

年代:1984

数据来源: OVID

摘要:

The purpose of this project was to design compact, flexible, portable and modular instrumentation for clinical applications using radioisotopes. The instrumentation designed includes: (1) 3 and 5 nuclear counting channels with energy discrimination; (2) 5 nuclear counting channels without energy discrimination; (3) a pulse-height analyzer. Designed around anApple IIecomputer, the system cost is related to the interfaces and the Apple accessories chosen by the utilizer.

ISSN:0363-8855    

出版商:OVID    

年代:1984

数据来源: OVID

摘要:

A system for automated analysis of action potential characteristics utilizing analog and digital circuits for measuring characteristics in the voltage and time domain is described. A microcomputer is used to acquire, process and store the data, and may be programmed to follow rapid or transient changes on a beat-to-beat basis or slow changes and trends according to the experimental requirements. The system has been found useful in the basic electrophysiology laboratory.

ISSN:0363-8855    

出版商:OVID    

年代:1984

数据来源: OVID

摘要:

InChagas Cardiomyopathy, an immunological reaction is produced that leads to changes in the histological structure of the myocardium, which in turn cause dynamic disorders, as well as morphological alterations in the heart. In theHigh Frequency ECG (HFECG), which contains useful clinical information not recorded in the conventional ECG, the changes induced by Chagas disease produce a larger number ofnotchesin the QRS complex than those found in normal patients. Therefore,notch countsare used as an evidence of cardiac damage. In this paper, a system based on a commercially available personal computer is designed to automate the notch counting procedure. Using this system, the HFECG could be recorded from a larger number of patients making this technique potentially attractive for routine clinical use. Additionally, the subjectivity associated with the manual techniques could be eliminated. This paper presents the design of the instrumentation.

ISSN:0363-8855    

出版商:OVID    

年代:1984

数据来源: OVID