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M Oehmichen

Publications and source records attributed to M Oehmichen.

At least 73 records · Page 4Linked to original sources

[Methanol, isopropanol, n-propanol--endogenous formation affected by alcohol?].

Methanol, isopropanol and n-propanol are detected usually in blood samples during the determination of congeners. The ethanol-induces formation of methanol and isopropanol has been described formerly. Also little amount of n-propanol were detected in blood, which could not be reduced to the alcoholic beverages.

1-Propanol↗

[Scanning electron microscopy studies for the analysis of mixed script].

Mixed script is a criminalistic problem which--though it is described in different papers--is not systematically investigated. We, therefore, analyzed the mixed script produced by different instruments by SEM: pencil, ink/India ink, ball point pen, felt-tip pen, copied scripts and typewriter. The significance of REM investigations in mixed scripts is stressed.

Crime↗

Cytokinetics of epidermic cells in skin from human cadavers. I. Dependency on the postmortal interval.

Punch biopsies taken from the extensor side of the thigh of 35 human cadavers were incubated in vitro with radioactively labeled thymidine (3H-thymidine = 3H-TdR, 14C-thymidine = 14C-TdR) to determine whether a relationship exists between changes in the proliferative activity of the skin and the postmortal interval after irreversible cardiac arrest. The cadavers were stored at 4 degrees C. Cadavers with indeterminable time of death or presence of intoxication, drug therapy with cytostatic agents, or a skin disease were excluded from the study. Single, double, or multiple biopsies were performed on the same cadaver; single labeling with 3H-TdR was done in all cases; double labeling with 3H-TdR and 14C-TdR in selected cases. No relevant changes in the labeling index (mean, 2.39 +/- 1.03%) were demonstrable within the examined postmortal interval of 77.75 h. The DNA synthesis time (ts) was, on the average, 4.75 +/- 1.44 h; a certain relationship to the postmortal interval existed since ts declined with increasing storage time. The potential doubling time (tpot) decreased accordingly, beginning with 181.7 h (mean storage time, 29.9 h) and ending with 137.7 h (mean storage time, 41.7 h). No statistically relevant differences, however, were established at the 1% level. Whereas both labeling index and tpot during the early postmortal interval are comparable with observations in live humans, ts was relatively short as compared to that for the epidermis of live humans.

Adolescent↗

Cytokinetics of epidermic cells in skin from human cadavers. II. Dependency on sex, age, and site.

Kinetic data on the labeling index (LI), DNA synthesis time (ts), and potential doubling time (tpot) of epidermic cells in relation to sex, age, and site were obtained by in vitro incubation of skin cylinders from 45 human cadavers with DNA precursors 3H- and 14C-thymidine. In a first study on parts of the same material, it was established that LI over a period of more than 70 h and tpot over a period of at least 30 h remained essentially unchanged and are comparable with live humans, when the cadavers were stored at 4 degrees C. The following results were obtained: The female and male cadavers had a LI of 2.6% (+/- 0.8%) or 2.5% (+/- 0.8%), a ts of 3.9 h (+/- 0.2 h) or 5.0 h (+/- 1.6 h), and a tpot of 168.5 h (+/- 34.3 h) or 183.9 h (+/- 27.2 h). The LI for the thigh and knee ranged between 21.3% and 25.8% in different age groups. No statistically relevant differences were established between the sexes or among the age groups. Topographic allocation of the proliferative-kinetic data ultimately showed that, on the average, LI was relatively high at the elbow (3.1% +/- 1.0%) with short tpot (109.3 +/- 72.5 h) and a comparatively large epidermal diameter (47.1 microns); by contrast, LI at the lower abdomen was impressively low (2.1% +/- 0.8%), tpot relatively long (183.0 +/- 138.7 h) and mean epidermal diameter relatively small (23.0 microns). Nevertheless, no statistically relevant differences were established between data for elbow and lower abdomen or between other data for different sites. The proliferative-kinetic data for human cadavers were compared with data reported in the literature for live humans.

Adolescent↗

[Air embolism or putrefaction? Gas analysis findings and their interpretation].

Gas was detected in the hearts of 111 necropsy cases. The gas was quantified and then analyzed by gas chromatography. In 70 cases H2, a clear marker of putrefaction, could be identified in the samples. After critical consideration, air embolism was accepted in 36 of the remaining cases. In nearly all instances, severe skull trauma or stab wounds to the neck or clavicular region gave rise to the air embolism. When the gas analysis data were compared, clear-cut differences were found between the two groups of putrefaction and air embolism. CO2 concentrations below 15%, N2 concentrations above 70%, and a CO2/N2 ratio below 0.2 proved to be good criteria to determine an air embolism. However, gas volumes, O2 concentrations, and CO2/O2 ratios largely overlapped in the two groups. Air embolism samples consistently had lower O2 concentrations and higher CO2 concentrations than atmospheric air, and this was evidently independent from incipient putrefaction. We suggest that these deviations result from a gas exchange between the venous blood and the embolized air volume taking place in the right heart ventricle. The dimensions of the concentration shifts may be understood from severe agonal hypoxia and hypercapnia.

Carbon Dioxide↗