Medical instrumentation最新文献_第5页

Microcomputer analyses of clinical ERG, EOG, and other tests of retinal function. 临床ERG、EOG及其他视网膜功能测试的微机分析。

Medical instrumentation Pub Date : 1988-02-01

G Stanziano, H Kaplan, A Koblasz, K Davey

引用次数: 0

Evaluation of monoexponential extrapolation of transpulmonary thermal-dye kinetics by use of a new model-free deconvolution algorithm. 利用一种新的无模型反卷积算法评价经肺热染料动力学的单指数外推。

Medical instrumentation Pub Date : 1988-02-01

J C Böck, P Deuflhard, A Hoeft, H Korb, J Steinmann, H G Wolpers, G Hellige

{"title":"Evaluation of monoexponential extrapolation of transpulmonary thermal-dye kinetics by use of a new model-free deconvolution algorithm.","authors":"J C Böck, P Deuflhard, A Hoeft, H Korb, J Steinmann, H G Wolpers, G Hellige","doi":"","DOIUrl":"","url":null,"abstract":"This study evaluates the routine mathematic approach (monoexponential extrapolation) for analysis of transpulmonary thermal-dye dilution curves and estimates the effects of systemic-indicator recirculation by use of a deconvolution technique. Fifteen dogs anesthetized with N2O-piritramid were studied before and after induction of pulmonary edema by oleic acid. After introduction of central venous indicator (10 ml of a mixture of cold blood and indocyanine green dye), dilution data were recorded from the pulmonary artery and the ascending aorta. The conclusions were: (1) monoexponential extrapolation yields reasonably good estimates of the mean transit times of dye; (2) mean transit times of heat are usually overestimated by monoexponential extrapolation; (3) extravascular lung thermal volume assessed by monoexponential extrapolation is overestimated by 2.03 ml/kg of body mass under baseline conditions; and (4) the prepulmonary volume of distribution of heat exceeds that of dye by 1.4 ml/kg of body mass, thus increasing the overestimation of pulmonary extravascular heat-accessible space by the conventional technique.","PeriodicalId":76133,"journal":{"name":"Medical instrumentation","volume":"22 1","pages":"20-8"},"PeriodicalIF":0.0,"publicationDate":"1988-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"14409931","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Why we need a tough national science advisor. 为什么我们需要一个强硬的国家科学顾问。

Medical instrumentation Pub Date : 1988-02-01

E Harken D

引用次数: 0

Electrically heated simulator for relative evaluation of alternative infant incubator environments. 电热模拟器的相对评价替代婴儿孵化器环境。

Medical instrumentation Pub Date : 1988-02-01

J S Ultman, S Berman, P Kirlin, J M Vreslovic, C B Baer, K H Marks

{"title":"Electrically heated simulator for relative evaluation of alternative infant incubator environments.","authors":"J S Ultman, S Berman, P Kirlin, J M Vreslovic, C B Baer, K H Marks","doi":"","DOIUrl":"","url":null,"abstract":"A 10.9-cm diameter, copper ellipsoid was electrically heated to provide a simulation of sensible heat transfer from a newborn infant. The use of this simulator to determine mean radiant temperature and convective heat-transfer coefficient was demonstrated in three commercial incubators: the Isolette (Model C-86, Narco/Air Shields); the Armstrong Care-ette (Ohio Medical Products); and the I. C. (Ohmeda). The relative performance of these environmental therapeutic devices in shielding an infant against radiant heat loss was judged by the deviation of mean radiant temperature from incubator air temperature, which was varied from 32-36 degrees C. Whereas the I. C. incubator exhibited a radiant temperature always 0.5 degrees C less than air temperature, the Care-ette incubator showed radiant temperatures of 4.0-5.5 degrees C below air temperature, and the Isolette displayed radiant temperatures of 2.7-4.7 degrees C (inner wall removed) and 2.0-3.8 degrees C (inner wall inserted) below air temperature. The relative performance of the incubators in preventing convective heat loss was judged from the magnitude of the convective heat-transfer coefficient, hv. The I. C. incubator had an hv = 4.52 W/m2/degrees C; the Care-ette, 5.55 W/m2/degrees C; and the Isolette 7.19 W/m2/degrees C (inner wall removed) and 6.23 W/m2/degrees C (inner wall inserted). Although an ellipsoid simulator is not an anatomically correct substitute for an infant, it does provide a reliable and convenient comparison of steady-state heat transfer characteristics of alternative environmental devices.","PeriodicalId":76133,"journal":{"name":"Medical instrumentation","volume":"22 1","pages":"33-8"},"PeriodicalIF":0.0,"publicationDate":"1988-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"14485005","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

An assessment of blood vessel vasoactivity using photoplethysmography. 利用光容积脉搏波描记术评估血管活性。

Medical instrumentation Pub Date : 1988-02-01

M L Evans, L A Geddes

引用次数: 0

Microwave desorption: a combined sterilizer/aerator for the accelerated elimination of ethylene oxide residues from sterilized supplies. 微波解吸:用于加速消除灭菌用品中环氧乙烷残留物的组合消毒器/曝气器。

Medical instrumentation Pub Date : 1988-02-01

A H Samuel, I P Matthews, C Gibson

{"title":"Microwave desorption: a combined sterilizer/aerator for the accelerated elimination of ethylene oxide residues from sterilized supplies.","authors":"A H Samuel, I P Matthews, C Gibson","doi":"","DOIUrl":"","url":null,"abstract":"Ethylene oxide gas is widely used in medical and related facilities for low-temperature sterilization of surgical devices. Evidence of its toxicity and, in particular, its mutagenicity and carcinogenicity provide sufficient reasons for caution in its use and for minimizing exposure. Little advancement has been made in the removal of ethylene oxide residuals from plastics into which the gas is heavily absorbed during sterilization, despite the fact that the gas has been used for 20 years or more. This article describes a novel process (PCT Application/GB85/00509) in which microwave irradiation of ethylene oxide-sterilized materials is utilized to enhance the rate at which the gas is desorbed. The experimental apparatus is described, and an explanation of the effect of microwaves on the energy of activation for diffusion is given. Data are presented in support of the authors' claim of a 400% improvement in the efficiency of the new process over conventional aeration procedures. The advantages and economy of an integrated sterilizer/microwave-enhanced desorber are discussed in the context of the implications that arise from the current regulatory debate.","PeriodicalId":76133,"journal":{"name":"Medical instrumentation","volume":"22 1","pages":"39-44"},"PeriodicalIF":0.0,"publicationDate":"1988-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"14484143","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Ambulatory monitoring of the ST segment, using direct-recording Holter systems. 动态监测ST段，使用直接记录动态心电图系统。

Medical instrumentation Pub Date : 1988-02-01

J Brose, G Flachenecker, A Frey

引用次数: 0

A multichannel PWM telemetry system for kinematic gait analysis. 用于运动步态分析的多通道PWM遥测系统。

Medical instrumentation Pub Date : 1987-12-01

G F Harris, D C Jeutter, B C Bergner, D V Matesi, N J Pelc

引用次数: 0

Analysis of the current-density distribution from a tapered, gelled-pad external cardiac pacing electrode. 锥形凝胶垫心脏外起搏电极电流密度分布分析。

Medical instrumentation Pub Date : 1987-12-01

C R Williams, L A Geddes, J D Bourland, E S Furgason

{"title":"Analysis of the current-density distribution from a tapered, gelled-pad external cardiac pacing electrode.","authors":"C R Williams, L A Geddes, J D Bourland, E S Furgason","doi":"","DOIUrl":"","url":null,"abstract":"We have designed a high-impedance (5000 omega-cm), tapered, gelled-pad, external cardiac pacing electrode that limits the migration of charges to the perimeter of a circular electrode and produces a more uniform current-density distribution than external cardiac pacing electrodes in clinical use. A computer simulation was developed that uses cylindrical coordinates to analyze the current-density distribution at the interface between the electrode and human tissue. Our computer simulation analyzed 32 different electrodes, and the results showed that the gelled-pad thickness, the gelled-pad taper, and the radius of the conducting disk were not significant parameters in determining the current-density distributions for low-resistivity electrodes. Those parameters were, however, significant for high-resistivity electrodes. We defined the optimum resistivity as that at which the tapered, gelled-pad electrode produces the most uniform current-density distribution and delivers the most current to human tissue. When evaluating electrodes at the optimum resistivity, we determined that the peak current density of the tapered, gelled-pad electrode was 50% lower than that of the clinically available electrodes, while delivering 58% more current to the human tissue.","PeriodicalId":76133,"journal":{"name":"Medical instrumentation","volume":"21 6","pages":"329-34"},"PeriodicalIF":0.0,"publicationDate":"1987-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"14556083","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Neuronet: implementation of an integrated clinical neurophysiology system. Neuronet:集成临床神经生理学系统的实现。

Medical instrumentation Pub Date : 1987-12-01

D N Krieger, R M Lofink, E L Doyle, G Burk, R J Sclabassi

引用次数: 0