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Biomedical subjects

S J Schneider

Publications and source records attributed to S J Schneider.

7 recordsLinked to original sources
PubMed1992

Lambdoid phages as elements of bacterial genomes (integrase/phage21/Escherichia coli K-12/icd gene).

The lambdoid phages are a group of related temperate bacteriophages that lysogenize by site-specific recombination with the bacterial chromosome. Various members of the group have different specific chromosomal insertion sites, despite the fact that the enzymes catalyzing the insertion (integrases) appear to be all descended from a common ancestor. Insertion sites are not located randomly on the E. coli chromosome but are restricted to one segment of the map; also, most prophages are oriented in the same direction along the chromosome. Lambdoid phage 21 inserts within the isocitrate dehydrogenase gene and introduces an alternative 165 bp 3' end for that gene. A defective element (e14) inserts at the same position. We suggest that this mode of insertion arose from insertion of an ancestral phage to the right of icd which then picked up part of the icd gene by abnormal excision and speculate that, at an earlier time, phages may have arrived at their present locations by a process of chromosomal walking.

Bacterial Proteins↗
PubMed1992

Complications of ventriculoperitoneal shunt procedures or hydrocephalus associated with vein of Galen malformations in childhood.

Twenty children with vein of Galen malformations and hydrocephalus required a ventriculoperitoneal shunt. Shunt placement was associated with a 70% incidence of complications that included status epilepticus in 3 patients, intraventricular hemorrhage in 7 patients, and subdural hematoma or hygroma in 5 patients. Based upon this experience, the authors recommend the use of preoperative prophylactic anticonvulsants and the placement of medium pressure frontal ventriculoperitoneal shunts. This report will address the overall experience with and the basis on which these therapeutic recommendations were made.

Adolescent↗
PubMed1979

Disability payments for psychiatric patients: is patient assessment affected?

Collected data for 348 veterans who had been patients at a psychiatric hospital: MMPI results, number of days of hospitalization already past when the MMPI was taken, length of the entire hospitalization during which the MMPI was taken are amount of disability payment at the time of the MMPI, and number of hospitalizations to date. The amount of disability payments was correlated significantly with the MMPI scales associated with psychosis. Veterans who were not receiving disability payments but who later obtained payments appeared more severely psychiatric on the MMPI than others without payments, but were less willing to report their strengths. Those who received only small payments failed to report improvement in the early part of hospitalization and were hospitalized disproportionately to their symptoms, unlike those with maximum payments or rejected claims for payments. It is concluded that patients eligible for larges payments may alter their self reports, but that disability payments nonetheless are awarded only in proportion to actual impairment.

Adult↗
PubMed1979

Strategies for attention allocation in multiple input, multiple response tasks.

9 tasks involving multiple inputs and multiple responses were administered. The tasks involved monitoring, shadowing, and ignoring, in all combinations, monaural and dichotic meassages. Miss rates were compared to determine the effect of adding additional demands to different tasks. Results suggested that, when a demand was added to a task, attention was allocated away primarily from those demands already receiving the greatest amounts of attention, to accommodate the new demand. When the new demand drew attention toward a channel, those demands already receiving the least amounts of attention gained the largest amounts. There were several exceptions to these trends, suggesting that the total amount of effort available for allocation was apparently an important variable. The implication of the results for research in attention was discussed.

Acoustic Stimulation↗
PubMed1978

Speculating about cognitive experiments using schizophrenics.

Several models of selective attention are reviewed, emphasizing how breakdowns in various parts of each model could result in certain attentional deficits. It is concluded that some evidence suggests that the ability to mobilize attention may not be as impaired in schizophrenia as is the ability to choose which stimuli are appropriate for attention. If so, then in any cognitive experiment involving schizophrenics, any schizophrenic subject would be particularly distracted by certain extraneous stimuli, while other schizophrenic subjects would be particularly distracted by other stimuli. The importance of this possibility for cognitive research in schizophrenia is discussed.

Attention↗