摘要:

This review analyzes the regulations and control resulting from theMedical Device Amendments of 1976, and their effect onproduct integrity.There is a discussion on claims, safety considerations, recalls, cost factors, and the advantages and disadvantages of increasing governmental regulation of medical devices. A glossary of regulatory terms is included.

ISSN:0363-8855    

出版商:OVID    

年代:1979

数据来源: OVID

摘要:

Proton spin-spin relaxation time (T2) was measured at room temperature(-21oC) at 20 MHz, in human whole blood, plasma, serum, packed red cells, and hemoglobin for normal, and whole blood and plasma for selected pathological samples. Plasma and serum T2values are equal within experimental errors. The average plasma and packed red cells T2for normal blood remains essentially constant at 0.38 s and 0.12 s in the normal range of hemoglobin concentrations. T2of the whole blood, averaging (0.24 + .04) s, is linearly dependent on the hemoglobin concentration, and increases by about 33% from 9 to 17 g hemoglobin / 100ml blood. T2of extracted oxyhemoglobin varies predictably with time from extraction. Pathological samples show noticeable differences in plasma T2values, indicating the possibility of using NMR to distinguish between normal and pathological samples.

ISSN:0363-8855    

出版商:OVID    

年代:1979

数据来源: OVID

摘要:

Compatibility between living tissues and implanted materials may be impossible. An implant may be tolerated, however, for varying periods of time and a dynamic equilibrium between host and implant may be established. The effects of the implant on the host may be: acute toxicity, chronic toxicity, allergenicity, cancerogenicity, teratogenicity. The host environment may cause a breakdown of the implant (chemical or mechanical), and the breakdown products may again interact with the host.Biomaterials Scienceis a descriptive science; biomaterials research has produced various types of classifications. With further research it may progress to an explanatory science. A quantitative assessment of the tolerance of an implant, which is necessary as a basis for the formulation of standards and for the design of predictive tests, may not be possible until we can explain the dynamic equilibrium between host and implant.

ISSN:0363-8855    

出版商:OVID    

年代:1979

数据来源: OVID

摘要:

A modified Doppler ultrasound system has been developed which enables blood pressure measurements to be made noninvasively while a patient is undergoing a treadmill stress test. This system amplifies the Korotkoff sounds to an audible level while minimizing noise artifact, which was a problem in previous blood pressure monitoring systems. An investigation was also initiated to test the significance of using blood pressure measurements and the associated heart rate during the stress test as an additional diagnostic aid in the detection of coronary heart disease. The result of multivariate-discriminant analysis indicates that a possible difference exists in the relationship between systolic blood pressure and heart rate at increased levels of stress for normal patients, compared to those with coronary heart disease. Comparison with arteriography indicates that the stressed blood-pressure versus heart-rate relationship is a good indicator of coronary heart disease.

ISSN:0363-8855    

出版商:OVID    

年代:1979

数据来源: OVID

摘要:

A simple, low-cost computerizedminirecordsystem (minimal essential record) has been in operation at theJohns Hopkins Medical Clinicsince mid-1975. The system has three primary components: (a) theMinirecordwhich contains a listing of problems and medications, plus information about visits to other clinics, (b) anappointment systemused to organize materials prior to clinic encounters and assist in the follow-up of high risk special patients, and (c) anencounter data systemto prepare reports used for management, quality assurance and training. This paper describes the system's operation, and reports on its utility and cost.

ISSN:0363-8855    

出版商:OVID    

年代:1979

数据来源: OVID

ISSN:0363-8855    

出版商:OVID    

年代:1979

数据来源: OVID

ISSN:0363-8855    

出版商:OVID    

年代:1979

数据来源: OVID

ISSN:0363-8855    

出版商:OVID    

年代:1979

数据来源: OVID

ISSN:0363-8855    

出版商:OVID    

年代:1979

数据来源: OVID