摘要:

Drug nebulizers should be designed to produce an aerosol which efficiently targets drug to the respiratory tract. In this article we review the basic principles of aerosol generation from both jet and ultrasonic nebulizers, and the factors governing respiratory tract penetration and deposition. We review methods for accurate measurement of aerosol dose and size, with emphasis on evaporative effects and the implications to drug nebulizer design. We identify three forms of drug aerosol waste attributable to: generation of non-respirable aerosol, losses to the environment, and dead volume solution; and we consider how each may be minimized through good nebulizer design. Finally, we compare the relative merits of jet and ultrasonic nebulizers, and conclude by predicting a new trend in future drug nebulizer therapy.

ISSN:0309-1902    

DOI:10.3109/03091909209021962

出版商:Taylor&Francis    

年代:1992

数据来源: Taylor

摘要:

A pragmatic approach to interference in NMR and MRI systems is presented with the objective of raising the awareness of problems associated with larger installations. The basic premise is that an installation is a system composed of interconnected sub-systems, each with its own idiosyncracies. Consequently all problems should be considered from this view-point. Practical warnings and solutions are given along with simple mathematical equations to permit one to calculate some interference effects. Most problems are associated with RF and gradient sub-systems, so the main content deals with degradation of the NMR signal by noise and coherent RF interference and with the interaction of sub-systems. Attention is drawn to the correct identification of the source of a problem, and the importance of a well engineered solution.‘Quick-fix repairs’can lead to very baffling problems when the system is reconfigured for a different experiment.

ISSN:0309-1902    

DOI:10.3109/03091909209021963

出版商:Taylor&Francis    

年代:1992

数据来源: Taylor

摘要:

Reliability and validity of biparietal diameter (BPD) compared with head circumference (HC) measurement as an index of cranial growth was assessed. A significant correlation between BPD and HC (r = 0.857; p<0.0001) and an interobserver reliability of 92% were found. Infants' age and sex had independent effects on BPD growth rale. Very sick infants had a lower increase in BPD rate than healthy controls. It is suggested that in sick premature infants, when the head is encumbered by various types of apparatus, this technique might prove more feasible than HC measurement.

ISSN:0309-1902    

DOI:10.3109/03091909209021964

出版商:Taylor&Francis    

年代:1992

数据来源: Taylor

摘要:

We have evaluated a new, hand-held, electronic device to measure maximal respiratory pressures, and compared its performance in normal subjects against two pre-existing methods. This new device produces accurate, reproducible results and has the advantages of easy use and portability, which allow it to be used at the patient's bedside, outpatient clinic or pulmonary function laboratory.

ISSN:0309-1902    

DOI:10.3109/03091909209021965

出版商:Taylor&Francis    

年代:1992

数据来源: Taylor

ISSN:0309-1902    

DOI:10.3109/03091909209021966

出版商:Taylor&Francis    

年代:1992

数据来源: Taylor

ISSN:0309-1902    

DOI:10.3109/03091909209021967

出版商:Taylor&Francis    

年代:1992

数据来源: Taylor

ISSN:0309-1902    

DOI:10.3109/03091909209021968

出版商:Taylor&Francis    

年代:1992

数据来源: Taylor

ISSN:0309-1902    

DOI:10.3109/03091909209021969

出版商:Taylor&Francis    

年代:1992

数据来源: Taylor

ISSN:0309-1902    

DOI:10.3109/03091909209021970

出版商:Taylor&Francis    

年代:1992

数据来源: Taylor