PubMed Health⌕ Search

Biomedical subjects

G Merker

Publications and source records attributed to G Merker.

At least 55 records · Page 3Linked to original sources

The effect of O-(beta-hydroxyethyl)-rutosides on function and structure of the ganglion cells.

The effect of O-(beta-hydroxyethyl)-rutosides (Venoruton) on function and structure of the motor anterior-horn cells of the lumbar spinal cord was investigated under conditions of ischemia in the rabbit. The determination of the functional parameters of the ganglion cells, such as maximal function time (Fm), disappearance time (SFm), relative efficiency (La), and regeneration expenditure (Ea) revealed that 50 mg/kg of Venoruton injected prior to repeated aortic occlusion of short duration (occlusion time A = Fm and A = 2 Fm, respectively) caused the efficiency of the anterior-horn cells to be decreased. Both qualitative and quantitative analysis of the mitochondrial structure after prolonged aortic occlusion (15-25 min) revealed that after prior injection of Venoruton irreversible structural changes in the mitochondrial membranes of the ischemic area in the spinal cord occurred after aortic occlusion of 15 min duration. In the untreated controls such changes were not observed before 20 min of occlusion. The mitochondrial structure of the non-ischemic area in the spinal cord was found to be undamaged, however, in both controls and experimental animals. Venoruton given after prolonged aortic occlusion resulted in less pronounced structural changes of the mitochondria in the ischemic area of the experimental animals than those found in the untreated controls; paralysis of the hind extremities was found to occur only after prolonged occlusion (25 min), whereas in the controls such changes were already observed after 20 min of occlusion. Since no ultrastructural changes in the ganglion cells of the non-ischemic area in the in the lumbar spinal cord were observed after application of Venoruton, it is assumed that the decreased efficiency of the motor anterior-horn cells found in the ischemic area when Venoruton had been injected before the aortic occlusion may be due to reactions of the cell that only occur when the blood supply has been completely cut off and Venoruton is present at the same time.

Animals↗

[Further development of the program system for lung function diagnostics running on minicomputer C 8205 (author's transl)].

Starting from the level of 1972 the development is characterized in view of -- general technical, psychological and economical problems -- completion of the program library and the -- technique of semi-on-line data collection. The last point describes experiences using the system of VEB Funkwert Erfurt. Different levels of automatization in lung function labs are discussed.

Computers↗

[Computer measurement of residual volume and alveolar gas distribution parameters in epidemiological studies (author's transl)].

Starting from the quick helium-rebreathing-technique of Kowalski-Visser a method of combined measurement of residual volume and closing volume in one test was developed using automatic data - collection in 3 different variants, that is- automatic control during test- manual control during test and- manual control on the table. A computer program running on minicomputer Cellatron 8205 is described. Experiences using the different program-variants are discussed.

Diagnosis, Computer-Assisted↗

[Functional diagnosis of CNSLD in epidemiological surveys-results of the population study in Halle 1974 (author's transl)].

The problems of lung function testing methods in epidemiological studies were assessed in a study population of 853 men aged 40-70. The Helium-rebreathing-method, the X-ray densitometry, the oxygen-method were evaluated for the estimation of the residual volume in epidemiological conditions. The Pneumotest was proved for measurement of unequal ventilation. The necessity of reference values for these methods is discussed.

Adult↗

[Rapid test for quantitative proof of emphysema].

For the purpose of an aimed diagnostics near to practice of unspecific chronic pulmonary diseases a measuring place was developed, by means of which with simple performance of the experiments and short examination-time the determination of vital capacity, forced expiratory volume, maximal breathing capacity, the measurement of the O2-tension of the arterialised ear blood and the determination of the residual volume are possible. The determination of the residual volume is performed according to the classical O2-N2-gasmixture method using the spirotest device in connection with a bag-box system and the PO2-micro-measuring chamber. On 63 patients the residual volume was determined in this measuring place and compared with the rapid He-re-breathing method. The correlation analysis between the RVbody%TK- and the RVO2% TK-values with a correlation coefficient r = 0,887 ascertains the reliability of the demonstrated method. The results of a epidemiological study on 422 test persons on account of the close correlation between RVHe % TK and RVO2% TK with r = 0.62 prove the usability for examinations of the population.

Airway Resistance↗