PubMed Health⌕ Search

Biomedical subjects

R Brühl

Publications and source records attributed to R Brühl.

9 recordsLinked to original sources

Matter wave diffraction from an inclined transmission grating: searching for the elusive 4He trimer Efimov state.

The size of the helium trimer is determined by diffracting a beam of 4He clusters from a 100 nm period grating inclined by 21 degrees. Because of the bar thickness the projected slit width is roughly halved to 27 nm, increasing the sensitivity to the trimer size. The peak intensities measured out to the eighth order are evaluated via a few-body scattering theory. The trimer pair distance is found to be (r) = 1.1(+0.4)(-0.5) nm in agreement with predictions for the ground state. No evidence for a significant amount of Efimov trimers is found. Their concentration is estimated to be under 6%, less than expected.

Journal Article↗

[Histochemical and ultrastructural study of cytochrome-oxydase in basal cell epithelioma].

The activity of cytochrome-oxydase is less pronounced in the basal cell epithelioma than in the basal cells of the surrounding normal epidermis. The electron microscopic study of the localisation of the enzyme reveals that the cells of the basal cell epithelioma contain two types of mitochondria, the first of which having the same size as the epidermal mitochondria, and the other being giant mitochondria. The latter seem to be less active. The weak reactivity of the basal cell epithelioma for cytochrome-oxydase is probably due to the reduction of the cristae in mitochondria and to the functional deficiency of the giant mitochondria.

Basal Cell Carcinoma↗

[Ultrastructure of solid basalioma. A morphometric study (author's transl.)].

A morphometric investigation was made on mitochondria of basalioma cells and the cells of the basal layer of the epidermis lying over the tumor. The mitochondria of the basalioma cells occupy 4.7% and of the epidermal basal cells 5.3% of the cytoplasm. The number of mitochondrial sections yields a relation of 6.6:10 in favor of the epidermal cells. These results demonstrate an alteration in the size of the basalioma cell mitochondria. The possible causes of this mitochondria enlargement were discussed. An attenuation of the activities of the mitochondrial, membrane-bound enzymes in the basalioma cells is caused in all probability primarily by a reduction of the cristae material in comparison to the basal epidermal cells. The nucleus-cytoplasm relation amounts to 6.3:10 in the basalioma cells and 3.0:10 in the basal epidermal cells.

Basal Cell Carcinoma↗