Hemispheric differences in the rates of information processing for simple non-verbal stimuli

An inspection time task, used to gauge differences in speed of information processing between the hemispheres, was administered to 22 normal subjects. It was found that the left visual field-right hemisphere (LVF-RH) exhibited an inferior performance relative to the right visual field-left hemisphere (RVF-LH). These results were consistent with other studies which have found an RVF-LH advantage for the processing of temporal/serial information. The possible ramifications of these results for models of asymmetry which do and do not attribute the left hemisphere's preferential capacity for language to these fundamental processes are then discussed.

Cavitation effects during lithotripsy. Part II. Clinical observations

Cavitation effects during biliary lithotripsy can produce sonographically visible microbubbles. The relationship between microbubble formation and clinical outcome of gallstone lithotripsy performed with a commercial lithotriptor was studied in 50 treatments in 29 patients. Microbubble formation in bile was a useful predictor of successful stone fragmentation in 31 of 34 treatments. Microbubble formation in the liver correlated with transient hepatocellular damage (as indicated by a twofold rise in serum transaminase levels) immediately after seven of 10 treatments. Advancing the focal volume of the lithotroptor deeper into the patient (placing the stone at the proximal point of the focal zone) may be a useful strategy for reducing hepatic cavitation effects, which appear to be responsible for temporary hepatocellular damage.

Relationship between stone motion, targeting, and fragmentation during experimental biliary lithotripsy

In vitro experiments in an anthropomorphic phantom were performed to clarify the relationship between stone motion, targeting, and fragmentation. Stone motion was minimized by pinning the stone against the dependent wall of a mock gallbladder cavity during shock wave treatment. Fragmentation was most effective (probably due to increased cavitation effects) when the shock wave traversed fluid at the point of its impact with a stone. The results suggest that treatment with the patient in the supine or oblique position may produce a better outcome than treatment in the prone position. Buoyant stones exhibited the greatest motion, which was often to-and-fro in nature. Although restricting the size of the mock gallbladder cavity reduced stone motion, maintaining a 1-cm fluid path was beneficial for achieving optimal pulverization.

Health characteristics by occupation and industry of longest employment

Includes estimates on length of longest job held, limitation of activity, disability days, incidence of acute conditions, persons injured, hospitalizations, and utilization of medical and dental services of persons aged 17 years and over in the civilian noninstitutionalized population. These estimates are presented by occupation and industry of longest employment for those who had ever worked. Estimates are based on data collected in the National Health Interview Survey of 1980.

Hemiazygos continuation of a left inferior vena cava: CT appearance

The CT appearance of hemiazygos continuation of a left-sided inferior vena cava is presented along with discussion of associated anomalies.

The relation between degree of blood pressure reduction and mortality among hypertensives in the Hypertension Detection and Follow-Up Program

The relation between degree of diastolic blood pressure reduction and mortality was examined among hypertensive persons in the Hypertension Detection and Follow-up Program. This program, conducted from 1973-1979, was a multicenter community-based trial, which followed 10,940 hypertensive participants for five years. The one-year annual visit was the first occasion on which change in blood pressure could be measured on all participants. During the subsequent four years of follow-up on 10,053 participants, 568 deaths occurred. With time-dependent life tables and time-dependent Cox life table regression analyses, the existence of a quadratic function which modeled the relation between diastolic blood pressure reduction and mortality was supported, even after adjusting for other risk factors. The minimum mortality hazard ratio, based on a particular model, occurred at a diastolic blood pressure reduction of 26.2 mmHg (standard error = 13.4) in the whole population and 10.0 mmHg (standard error = 5.3) in the baseline diastolic blood pressure stratum 90-104 mmHg. After this reduction, there was a small increase in the risk of death. There was no evidence of the quadratic function after fitting the same model with systolic blood pressure. Methodological issues involved in studying a particular degree of blood pressure reduction were considered. The confidence interval around the change corresponding to the minimum hazard ratio was wide, and the obtained blood pressure level should not be interpreted as a goal for treatment. Blood pressure reduction was attributed not only to pharmacologic therapy but also to regression to the mean, and to other factors unrelated to treatment.

Two-compartment Markov regression analysis

This paper presents a computer program for estimating transition rates between states in a two-compartment Markov process, where the rates are functions of covariates. Parameters are estimated by the method of maximum likelihood using the Newton-Raphson iterative procedure. The program provides statistics for testing hypotheses concerning regression coefficients and calculates observed versus expected values in order to assess the fit of the model to the data.