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991.
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D Karczewicz T Baranowska-George O Palacz E Tokarz-Sawińska W Stankiewicz Z Krzystolik W Lubiński K Ko?mider 《Klinika oczna》1989,91(1):9-11
Presented are the results of examination of 75 men, workers of the Chemical Works in Police, in whom in the scheme of complex clinical examinations detailed ophthalmological examinations have been carried out. The period of a professional contact with fluor amounted 6-15 years. The examined persons showed a variety of changes; the most important were opacities of the lens capsule, attenuation of the retinal arteries and a pathological record of the ERG. 相似文献
994.
Time domain formulation of pulse-Doppler ultrasound and blood velocity estimation by cross correlation 总被引:5,自引:0,他引:5
The Doppler effect is usually described as a frequency shift of the backscattered signals from moving targets with respect to the frequency transmitted. Recently, real-time blood flow imaging has become possible thanks to the development of a new velocity estimator based on phase-shift measurements of successive echoes. However, this method suffers from the well-known limitations of pulse-Doppler instruments. A new formulation is presented which describes the pulse-Doppler effect on the successive echoes from a cloud of moving targets as a progressive translation in time due to the displacement of the scatterers between two excitations. This approach allows us to generate efficiently computer-simulated data in order to evaluate accurately the various processing techniques. Furthermore, it leads to a novel class of velocity estimators in the time domain which measure the time shifts which are proportional to the local blood velocity. Among them, the cross correlation of the received rf signals turns out to be well suited. A local cross-correlation function is first calculated from a consecutive pair of range-gated echoes and the time shift is then determined by searching for the time position with the maximum correlation. The time-correlation technique is shown to provide accurate velocity profiles with broadband transducers. Moreover, the classical velocity limitation of pulse-Doppler is overcome because there is no ambiguity in measuring a time shift instead of a phase shift. These major advantages should make quantitative flow mapping possible and more reliable. 相似文献
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Although clinicians generally agree that patients with antisocial personality disorder should not be treated on general psychiatry units, little is known about the response to hospital treatment of personality disorder patients who have antisocial features or traits. In a study to identify predictors of positive and negative response to hospitalization, charts of all patients discharged from a private hospital with diagnoses of antisocial personality disorder or antisocial features over 52 months were reviewed. As a group the 33 patients did not respond well to treatment, and 70 percent left treatment prematurely. Significant predictors of negative response were histories of felony arrest and conviction; a history of repeated lying, aliases, and conning; and an unresolved legal situation at admission. Positive response was related to the presence of anxiety and an axis I diagnosis of depression. The authors believe that antisocial personality disorder is often underdiagnosed and that countertransference can present a significant obstacle to treatment of antisocial patients. 相似文献
998.
Pinhole collimator scintigraphy in differential diagnosis of metastasis, fracture, and infections of the spine 总被引:1,自引:0,他引:1
The informational gains obtained by the use of pinhole collimator scintigraphy (PCS) have been well documented. The present study has been undertaken to prospectively investigate its efficacy in diagnosing several commonly occurring spinal diseases. Patient material consisted of metastatic cancer (39 vertebrae), compression fractures (33 vertebrae), tuberculous spondylitis (17 vertebrae), and pyogenic spondylitis (six vertebrae). PCS findings were characterized in terms of localization, appearance, and homogeneity of abnormal radionuclide accumulation. Thus, metastatic cancer manifested as diffusely or focally homogeneous accumulation within the vertebral body or as a typical short-segmental accumulation along the end-plate, whereas compression fracture manifested as characteristic board-like accumulation along the entire length of end-plates. Tuberculous spondylitis, on the other hand, revealed homogeneous accumulation throughout the vertebral body, and pyogenic spondylitis revealed accumulation at the end-zone of opposing vertebral bodies giving sandwich-like appearance. The disk space at the affected level was not narrowed in the former two diseases but it was narrowed in the latter two. It was concluded that PCS may be useful in differentiating metastatic cancer, compression fracture, tuberculous spondylitis, and pyogenic spondylitis. 相似文献
999.
Reported here is a case of axillary artery aneurysm secondary to crutch trauma as a source of emboli to the upper extremity. This patient along with several reported in the literature was initially diagnosed and treated for brachial artery embolism. It is believed that awareness of this entity as a cause of forearm and hand ischemia is important in planning the appropriate surgical therapy. 相似文献
1000.
The effects of acute blood volume reduction induced by haemodialysison diastolic time intervals were studied in 19 patients by echo-and phonocardiography. Haemodialysis significantly decreasedleft ventricular diameters. The isovolumic relaxation time wasprolonged and negatively correlated with left ventricular enddiastolic dimensions. To study the effect of load reductionon left ventricular filling time, cardiac cycles with the sameRR interval, before and after haemodialysis, were compared.At any given RR interval dialysis resulted in a significantprolongation of the filling time. This study shows that diastolictime intervals are dependent on left ventricular loading conditions,and this effect should be considered when these time intervalsare evaluated in the clinical setting. 相似文献