A series of GaN x As 1 m x /GaAs quantum well structures with well widths of about 20 nm and x varying between 1% and 3.5% has been grown by metal-organic vapour phase epitaxy. We have studied the ...evolution of the quantum well states under hydrostatic pressure up to 20 kbar at 300 K by photomodulated reflectance (PR) spectroscopy. The energy positions of the quantum well transitions have been obtained by fitting the PR spectra. The pressure dependence of the allowed heavy-hole transitions e n hh n decreases with increasing n . This directly reflects the strong non-parabolic dispersion of the conduction band originating from the interaction of the N-impurity level with the bands of the GaAs host. The fitted energy positions and their pressure dependence can be well described by a 10 band k.p model. The observed splitting between the lowest light-hole and heavy-hole transitions are in agreement with a type I band alignment.
The influence of various CO2 laser surgical techniques on tumor behaviour was examined in an experimental model on C56BL/6 mice (n = 106) with Lewis Lung carcinomas and compared with that of scalpel ...excised tumors. Comparisons were made between the healing procedure, the local recurrence rate, metastatic behaviour and the survival rate (n = 86) of mice after laser surgical excision of tumors, using the superpulsed and continuous wave techniques, with and without additional vaporisation of the wound, as well as after general vaporisation only.
Psoriatische Onycho-Pachydermo-Periostitis Kroiss, M. M.; Vogt, T.; Finkenzeller, T. ...
Zeitschrift für Rheumatologie,
10/2002, Letnik:
61, Številka:
5
Journal Article
The focus of the present study is the optical characterisation of the novel direct band gap material Ga(NAsP) monolithically grown on Si substrate. Ga(NAsP)/(BGa)(AsP) multi-quantum-well ...heterostructures (MQWHs) were deposited by low temperature metal organic vapour phase epitaxy (MOVPE) in a commercial reactor system on nominally exact (001) Si substrates. In order to realise III/V laser diode the MQWH layer-stack was embedded in 1mum thick (BGa)P separate confinement structure (SCH) layers. Structure investigation proved that a precise strain-management allows for the deposition of thick III/V devices without the formation of cracks or misfit dislocations. First gain measurements at room temperature using the stripe-length method show a modal gain of more than 20cm -1 of the active Ga(NAsP) material monolithically integrated on Si substrates, which was discussed in detail.
In several phase II-trials encouraging tumour responses rates in advanced metastatic melanoma (stage IV; AJCC-classification) have been reported for the application of biochemotherapy containing ...interleukin 2. This study was designed to compare the efficacy of therapy with dacarbazine (DTIC) and interferon alpha (IFN-alpha) only to that of therapy with DTIC and IFN-alpha with the addition of interleukin 2 (IL-2) in terms of the overall survival time and rate of objective remissions and to provide an elaborated toxicity profile for both types of therapy. 290 patients were randomized to receive either DTIC (850 mg/m(2)every 28 days) plus IFN-alpha2a/b (3 MIU/m(2), twice on day 1, once daily from days 2 to 5; 5 MIU/m(2)3 times a week from week 2 to 4) with or without IL-2 (4.5 MIU/m(2)for 3 hours i.v. on day 3; 9.0 MIU/m(2) i.v. day 3/4; 4.5 MIU/m(2) s.c. days 4 to 7). The treatment plan required at least 2 treatment cycles (8 weeks of therapy) for every patient. Of 290 randomized patients 281 were eligible for an intention-to-treat analysis. There was no difference in terms of survival time from treatment onset between the two arms (median 11.0 months each). In 273 patients treated according to protocol tumour response was assessable. The response rates did not differ between both arms (P = 0.87) with 18.0% objective responses (9.7% PR; 8.3% CR) for DTIC plus IFN-alpha as compared to 16.1% (8.8% PR; 7.3% CR) for DTIC, IFN-alpha and IL-2. Treatment cessation due to adverse reactions was significantly more common in patients receiving IL-2 (13.9%) than in patients receiving DTIC/IFN-alpha only (5.6%). In conclusion, there was neither a difference in survival time nor in tumour response rates when IL-2, applied according to the combined intravenous and subcutaneous schedule used for this study, was added to DTIC and IFN-alpha. However, toxicity was increased in melanoma patients treated with IL-2. Further phase III trials with continuous infusion and higher dosages must be performed before any final conclusions can be drawn on the potential usefulness of IL-2 in biochemotherapy of advanced melanoma.
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