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Biomedical subjects

E Runge

Publications and source records attributed to E Runge.

At least 19 recordsLinked to original sources

Enhanced resonant backscattering of excitons in disordered quantum wells.

A clear signature of enhanced backscattering of excitons is observed in the directional resonant Rayleigh scattering of light from localized two-dimensional excitons in disordered quantum wells. Its spectral dependence and time dynamics are measured and theoretically predicted in a quantitative way. The intensity enhancement has a large momentum span extending beyond the external light emission cone. This is a consequence of the small localization length of the exciton as a massive particle probed close to the band bottom. The localization length can be controlled by the photon kinetic energy. This constitutes a qualitative difference to backscattering phenomena in other branches of physics.

Journal Article↗

Quantum mechanical repulsion of exciton levels in a disordered quantum well.

Spatially resolved photoluminescence spectra of a single quantum well are recorded by near-field spectroscopy. A set of over four hundred spectra displaying sharp emission lines from localized excitons is subject to a statistical analysis of the two-energy autocorrelation function. An accurate comparison with a quantum theory of the exciton center-of-mass motion in a two-dimensional spatially correlated disordered potential reveals clear signatures of quantum mechanical energy level repulsion, giving the spatial and energetic correlations of excitons in disordered quantum systems.

Journal Article↗

Patients with persistent APC-resistance without factor V Leiden mutation.

BACKGROUND: Activated protein C (APC) resistance and factor V Leiden mutation are major risk factors for deep venous thrombosis. Previous work has led to the view that the coagulation phenotype and the genetic defect are associated in almost all patients. It has been reported about single APC-resistant patients without associated factor V Leiden, but significance and thrombotic risk of this constellation have not yet been established. PATIENTS AND METHODS: We tested 486 consecutive patients with deep venous thrombosis, arterial disease or other than vascular disease for APC-resistance with a factor VIII based assay. RESULTS: 149 patients (31%) showed a pathological APC-ratio. Sensitivity and specificity for detection of factor V Leiden were 100% and 40%, respectively. At 6 months follow-up APC-ratio returned to normal in 55% of the patients with initial pathological APC-resistance. At 12 months follow-up 91% of the patients with persistent APC-resistance showed a pathological ratio as well. CONCLUSIONS: Patients with APC-resistance not due to factor V Leiden can be attributed to one subset with reversible APC-resistance--possibly due to a hypercoagulable state in an acute thrombotic situation, and to another with persistent APC-resistance.

Activated Protein C Resistance↗

[Current therapy of chronic arterial occlusive diseases of the lower extremities].

Angiologists, vascular surgeons, and angiographers inform about the actual state of the therapy of the arterial occlusive diseases of the legs. The degree I of therapy comprises the conservative treatment for the improvement of the macrocirculation and the normalisation of the disturbed microcirculation, taking into particular consideration the therapy with antiviscositant drugs. The main chapter ends with the possibilities of the influence on the arteriosclerotic vascular processes as well as with the necessary rehabilitative measures. In the paragraph about the degree II of therapy the indications, contraindications, methods and results of the isolated and combined percutaneous transluminal angioplasty, the systemic and local fibrinolysis as well as the reconstructive vascular operations are represented.

Arterial Occlusive Diseases↗

[Whole blood viscosity in patients with acral arterial occlusive diseases and their modification by rheologically active drugs].

Measurements of the whole-blood viscosity in patients with organic and functional disturbances of the acral blood supply were performed. In comparison with the whole-blood viscosity in normal persons patients with acral occlusive diseases showed a significantly increased viscosity. On the other hand, in patients with functional disturbances of the acral blood supply no differences could be established. In a therapy study the good efficacy of rheologically effective medicaments could be demonstrated particularly as combination therapy of pentoxifylline, acetylsalicylic acid and tolazoline in patients with acral occlusive diseases. These medicaments should by all means be used together with the basic therapy. In functional disturbances of the blood supply should predominantly be maintained physiotherapeutic methods of treatment.

Adult↗

[Long-term study of angiologic patients with over 15 years of dispensary care with special reference to early manifesting angio-organopathies].

In our dispensary patients who were more than 15 years cared for angiologically a large proportion (33%) of patients is evident who fell ill already before the 40th year of age mostly under the clinical picture of an obliterating endangiitis. Contrary to the supposition that in these patients the so-called risk factors play an inferior role, after an observation period of more than 15 years a profile of risk factors was found which is similar to that of primary arteriosclerotics. Clearly less insignificantly in the younger group at first only one case of diabetes mellitus appeared. The patients with early manifested angioorganopathy are not less, possibly even earlier threatened by severe complications of the vascular disease on heart and brain. Moreover, the amputation rate and the appearance of a stage IV, despite in general more favourable courses, is greater in the younger patients than in the older ones.

Ambulatory Care↗