摘要:

In anesthetized rabbits, focused intense ultrasound has been found to produce initially increases in conduction and amplitude of light evoked potentials, followed by regular decreases in response upon continued irradiation. The time required to produce complete reversible loss of function was inversely proportional to the acoustic intensity. Temperature changes were directly related to dosage.

ISSN:0002-9408    

出版商:OVID    

年代:1968

数据来源: OVID

ISSN:0002-9408    

出版商:OVID    

年代:1968

数据来源: OVID

摘要:

The paper describes a procedure utilizing a modified biomicroscope and corneal toposcope for the objective determination of the physical parameters of the corneal cone (horizontal cone width and sagittal depth) and the development of a classification of the condition based on comparative ratios of the obtained data.The paper initially describes some existing classifications based on: (a) photo-keratoscopic findings: (b) correlation of the disease stage to visual acquity: (c) observable corneal changes associated with the disease severity; and (d) sequential studies utilizing an electron microscope.The paper then describes the research plan with emphasis on the specific instrumentation utilized and the types of data obtained. A discussion is presented of Lindstedt's device as altered by Sternström, and a procedure noted for the approximate alignment of the target on the corneal apex. By virtue of the methods described, it is felt that the practitioner will have the means to detect more accurately and chart the course of the keratonic condition.

ISSN:0002-9408    

出版商:OVID    

年代:1968

数据来源: OVID

ISSN:0002-9408    

出版商:OVID    

年代:1968

数据来源: OVID

摘要:

The handling of the unilateral aphakic patient is complex. A technique is described that allows the practitioner to take first steps toward restoring binocular vision in suitable cases. A reverse Galilezn telescope is partially incorporated in a contact lens placed in front of the aphakic eye. The negative portion of the telescope is incorporated in the spectacle frame. Several problems and fitting details are considered. An outline of the method employed is presented at the end of the article.

ISSN:0002-9408    

出版商:OVID    

年代:1968

数据来源: OVID

ISSN:0002-9408    

出版商:OVID    

年代:1968

数据来源: OVID

摘要:

Epithelial edema is probably the most common lesion resulting from corneal abuse, yet little is known of its physiological properties. Described here is the recovery time course of one type of edema (hypotonic imbalance) as monitored by one physiological inded: oxygen flux across the tear-epithelial interface.

ISSN:0002-9408    

出版商:OVID    

年代:1968

数据来源: OVID

摘要:

In the United States, pedestrian deaths account for nearly 20% of all traffic fatalities. During darkness the pedestrain's risk is increased. This risk is further increased if a pedestrian is wearing dark clothing or must travel on a roadway concurrently with a driver who has been drinking.In the laboratory phase of this study it was found that at low levels of illumination an individual's sensitivity to contrast decreases as his blood alcohol level increases. All subjects exhibited a significant (p<.01) decrease in contrast sensitivity at blood alcohol levels greater than 0.04%. In the road test phase of the study visibility distances were found to be unacceptably short for “dummy” pedestrians covered with black or gray fabric. Dummies covered with white fabric were safely visible for a driver traveling up to a speed of 50 M.P.H.: however, only reflectorized dummies were safely visible above that speed. At blood alcohol levels greater than 0.04% all of the observers exhibited a significant (p<.01) decrease in the mean visibility distance for each of the simulated pedestrian conditions.

ISSN:0002-9408    

出版商:OVID    

年代:1968

数据来源: OVID

ISSN:0002-9408    

出版商:OVID    

年代:1968

数据来源: OVID

ISSN:0002-9408    

出版商:OVID    

年代:1968

数据来源: OVID