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Biomedical subjects

B Meyer

Publications and source records attributed to B Meyer.

At least 379 records · Page 21Linked to original sources
PubMed1981

Heat shock phenomena in Chironomus tentans I. In vivo effects of heat, overheat, and quenching on salivary chromosome puffing.

Incubation of 4th instar larvae of Chironomus tentans at elevated temperatures leads in salivary and Malpighian chromosomes to the appearance of 4-5 new puffs. Previously present puffs, particularly Balbiani rings in salivary chromosomes, become drastically reduced. The reactions of region IV-5C and Balbiani ring 1 and 2 in salivary glands are quantitatively analyzed. Statistically significant heat shock effects are observed already after 5 min and reach a maximum between 30 and 60 min. The effective temperature range is small (between 33 to 40 degrees C) with an optimum at 37 degrees C. Above 40 degrees C, i.e., at overheat shock temperatures, heat shock reactions are suppressed. Larvae heat or overheat shocked for 1-7 h or 15-30 min, respectively, survive when returned to normal culturing temperatures. The recovery from heat shock of the puffing pattern occurs in two phases: a fast one (10-20 min) and a slow one (up to 5 h) sometimes separated by a period of backlash. Quenching of overheat shocked larvae does not result in a delayed heat shock reaction.

Animals↗
PubMed1981

Renal Histidinuria.

One patient with abnormal histidinuria and a normal plasma histidine concentration is presented. This patient had myoclonic seizures like another patient previously reported with histidinuria. The effect of a peroral histidine loading test was studied. The relationship between renal histidinuria and neurological abnormalities is discussed.

Amino Acid Metabolism, Inborn Errors↗
PubMed1981

[Multiple electrode cochlear implants : clinical results (author's transl)].

Multiple electrode cochlear implants were employed in 34 patients with total deafness (25 cases of acquired deafness of an adult age, and 22 cases of congenital or neonatal deafness). Complications encountered initially (eardrum perforation, receiver breakdown) are no longer observed, but emphasis has also to be placed on the reliability of the electrode-nerve interface, which remained unaltered after a follow-up period of nearly five years. The advantages of the method are that it enables frequency discrimination, followed by that of phonemes and finally words and phrases, without the need for up-reading, results being variable from one case to another. Results are dependent on the effectiveness of the electrode-nerve interface and the intellectual development of the patient. Only measurable objective results are reported.

Adolescent↗
PubMed1981

[Respiratory sequelae of severe measles (author's transl)].

Six healthy children, 5 boys and 1 girl aged from 13 months to 4 years had a severe measles bronchopneumonia. The end result is established chronic airflow obstruction. On a background of fairly severe respiratory failure there were paroxysms of breathlessness with fever, wheezes and cyanosis which were little affected by bronchodilators or steroids. The anatomical basis of this syndrome is before all else a bronchiolar obstruction, shown at autopsy in a child dying after four months of the illness. But also there is a disorder of the large bronchi with bronchiectasis and problems with ventilation centrally and/or peripherally. The major radiological signs are airways distension which is always clearly in keeping with emphysema and a thickening of the peri-bronchial walls which are clearly visible on tomography. Thus it appears that measles, as with other respiratory viruses, can lead to permanent sequelae in very young children. It is however possible that the respiratory sequelae may be due to associated viral infections, with adenovirus in particular. On the practical level, the occurrence of an early and severe measles pneumonia in a young child and its persistence with a hypoxia and a lowering of dynamic compliance requires a prolonged follow up and a guarded prognosis. Unfortunately the treatment of this type of chronic airflow obstruction is only symptomatic.

Airway Obstruction↗
PubMed1980

[Experimental studies on various model material. 3. Dimensional behavior and reproductive fidelity as compared to those of elastomers].

Bandless impressions of tooth stumps obtained with the model materials Begolith, Dentaloc, Tewestone, Impredur and Keramid-Cement in combination with the elastic impression materials Silcoflex, Sanal/Silcoflex, Xirux/Xirux F and Impergum were studied in relation to dimensional behavior and reproduction fidelity. With reference to these parameters as well as to the hardness and abrasive behavior of the model materials after processing at various temperatures, recommendations are made for the optimum combination of these two groups of materials in practice.

Acrylic Resins↗
PubMed1980

The development of girls' sex-role attitudes.

The present study investigated girls' perceptions of the adult female role. It focused upon the relative impacts of maternal variables, societal stereotypes, and age upon girls' sex-role concepts. Subjects were 150 girls, ages 6--8 and 10--12, from working-class families in rural Ohio. Several measures were administered to each girl to assess the nature of her sex-role attitudes and aspirations. Questionnaires were sent home to participating mothers to determine maternal sex-role attitudes and aspirations. Questionnaires were sent home to participating mothers to determine maternal sex-role attitudes, maternal employment status, and maternal role satisfaction. The results supported a cognitive-developmental explanation of sex-role attitude development. Younger girls had significantly more sex-typed role prescriptions and aspirations than older girls. The older girls' sex-role attitudes and aspirations correlated significantly with their mothers' sex-role attitudes and goals for their daughters' futures. Maternal employment had no effect on girls' perceptions of the adult female role. It is suggested that this lack of effect may be due to the working-class background of the subjects.

Attitude↗