Radiology reports: assessment of a 5,000-word speech recognizer

A prototype 5,000-word recognizer for the generation of radiologic reports by voice entry was evaluated. The system had a capacity sufficient enough to include all radiologic examinations and all desired words in one lexicon. The lack of such a capacity had been identified as a major limitation of a 1,000-word system previously evaluated. Overall reliability in word recognition was 98%. The device may be widely applicable for use in any radiology practice.     

Paraspinal lipomatosis: a benign mass

Paraspinal lipomatosis usually occurs in patients with steroid excess. In two patients a paraspinal mass was detected on conventional radiographs and was subsequently shown to represent benign fat deposition on computed tomography, thereby obviating further studies. Neither patient had been receiving steroids. Paraspinal lipomatosis may be the cause of a benign mass and may be considered in the differential diagnosis of this finding.     

Diagnosis of internal jugular vein thrombosis

Six patients, aged 14-83 years, were shown by computed tomography (CT) to have thromboses of the internal jugular vein. In all cases, medical attention was sought only after a delay (4-21 days). In no case was the provisional clinical diagnosis correct, with working diagnoses ranging from abscess to neoplasm. A wide variety of likely causes was discovered, including venous catheters, local malignancy, infective cervical adenopathy, and polycythemia. CT showed distended veins with enhancing walls, low-attenuation intraluminal filling defects, and swelling of the adjacent soft tissues. Four of the six patients also underwent ultrasound examinations, which showed the veins to be distended and nonpulsatile, with internal echoes. Both modalities proved reliable and accurate. Because of the subtle and often non-specific clinical findings, it is likely that more clinically unsuspected cases will be encountered by the radiologist.     

A fundamental step-transition in retinal function at low light intensities

There appears to be a fundamental step-transition in retinal function at low light intensities, close to the scotopic-mesopic transition. This step-transition is observed for elements of the retinal dark-light switch, which has been described in the chicken retina. Over the same range of light intensities, there is a step-transition in photoreceptor retinomotor movements and in the coupling of horizontal and All amacrine cells, which suggests a switch in retinal circuitry from rod-processing to cone-processing regimes. A similar step-transition in pineal function suggests that the retinal step-transition signals to the central circadian systems. Finally, this step-transition may also inhibit eye growth, and thus be responsible for the reported diurnal rhythm in eye growth. Disturbances to this step-transition may be the initial cause of disordered eye growth in the form-deprivation myopia paradigm.     

The providers of health services in Lebanon: a survey of physicians

Background  

Emerging from civil distress carries with it major challenges to reforming a health system. One such challenge is to ensure an adequate supply of competent human resources. The objective of this study was to assess the supply of physicians in Lebanon in 1998, with an assessment of their practice patterns and capacity building.     

Role of membrane lipids in cold agglutination of human erythrocytes

The membrane lipid fluidity of normal human erythrocytes was modified by enrichment and depletion in cholesterol, and the expression of I and SP1 antigens was assayed by quantitative hemagglutination from 4 degrees to 24 degrees C by use of a continuous flow system. Below 16 degrees--18 degrees C, cholesterol enrichment increased and cholesterol depletion decreased percent agglutination. As temperatures approached approximately 18 degrees--20 degrees C, differences in agglutination between modified and unmodified erythrocytes became insignificant despite marked differences in lipid fluidity at that temperature. Thus, fluidity changes alone cannot be responsible for the effect of membrane cholesterol on cold agglutination. In an additional study, the temperature dependence of a relative equilibrium association constant, estimated by probit analysis of percent agglutination at various antisera concentrations, was biphasic with a sharp break at 16 degrees C. Our studies are consistent with the hypothesis that I and Sp1 antigens preferentially partition into a lipid domain that forms during lateral phase separation of membrane lipid developing at low temperature. A resulting increase in antigen density would then become responsible for augmented agglutination by specific antibody.