847 research outputs found
Embolization in an adrenocortical carcinoma as palliative therapy
Background: With an annual incidence of 0.2% of new cases per 100,000 inhabitants, adrenocortical carcinoma is rare. In advanced tumor only palliative treatment modalities are practicable. Because of scarcity of the tumor, standard treatment has not been defined. The decision on therapy frequently depends on the individual situation. Tumor embolization and chemotherapy are amongst the possible options. Patient and Methods: We report on a case of a 32-year-old female patient with a large-volume hormonally active adrenocortical carcinoma and hematogenous liver metastases. This carcinoma was confirmed histologically by means of liver biopsy. Owing to the large tumor extent and metastatic spreading and also in view of the poor general condition of the patient, curative surgical therapy was not possible. For this reason, a local approach was chosen primarily with transarterial tumor embolization at the capillary level. Systemic chemotherapy was given afterwards. Results: Improvement of the patient's general condition, especially the pronounced pain symptoms, could be achieved for a short time by the embolization: both, the patient's clinical condition and the laboratory test parameters improved. However, a rapid tumor progression occured under chemotherapy, which was started after embolization. Conclusion: In advanced adrenocortical carcinoma, tumor embolization can lead to a stabilization of the disease and improvement of the symptoms as appraised by palliative criteria in some patients
Ground state hyperfine splitting of high Z hydrogenlike ions
The ground state hyperfine splitting values of high Z hydrogenlike ions are
calculated. The relativistic, nuclear and QED corrections are taken into
account. The nuclear magnetization distribution correction (the Bohr-Weisskopf
effect) is evaluated within the single particle model with the g_{S}-factor
chosen to yield the observed nuclear moment. An additional contribution caused
by the nuclear spin-orbit interaction is included in the calculation of the
Bohr-Weisskopf effect. It is found that the theoretical value of the wavelength
of the transition between the hyperfine splitting components in ^{165}Ho^{66+}
is in good agreement with experiment.Comment: 12 pages, Late
General theory of three-dimensional radiance measurements with optical microprobes
Measurements of the radiance distribution and fluence rate within turbid samples with fiber-optic radiance microprobes contain a large variable instrumental error caused by the nonuniform directional sensitivity of the microprobes. A general theory of three-dimensional radiance measurements is presented that provides correction for this error by using the independently obtained function of the angular sensitivity of the microprobes. © 1997 Optical Society of America
Theory of equidistant three–dimensional radiance measurements with optical microprobes
Fiber-optic radiance microprobes, increasingly applied for measurements of internal light fields in living tissues, provide three-dimensional radiance distribution solids and radiant energy fluence rates at different depths of turbid samples. These data are, however, distorted because of an inherent feature of optical fibers: nonuniform angular sensitivity. Because of this property a radiance microprobe during a single measurement partly underestimates light from the envisaged direction and partly senses light from other directions. A theory of three-dimensional equidistant radiance measurements has been developed that provides correction for this instrumental error using the independently obtained function of the angular sensitivity of the microprobe. For the first time, as far as we know, the measurements performed with different radiance microprobes are comparable. An example of application is presented. The limitations of this theory and the prospects for this approach are discussed. © 1996 Optical Society of America
Microenvironment and photosynthesis of zooxanthellae in scleractinian corals studied with microsensors for O2, pH and light
During experimental Light-dark cycles, O-2 in the tissue of the colonial scleractinian corals Favia sp. and Acropora sp. reached >250% of air saturation after a few minutes in Light. Immediately after darkening, O-2 was depleted rapidly, and within 5 min the O-2 concentration at the tissue surface reached 6 times higher at a saturating irradiance of 350 mu Ein m(-2) s(-1) than the dark respiration measured under identical hydrodynamic conditions (flow rate of 5 to 6 cm s(-1))
- …