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Background. Melanoma, once considered a rare form of cancer, is increasing in incidence throughout the world. The prognosis of malignant melanoma is inversely related to the depth of tumor invasion. Methods. Twenty-seven patients were treated with r.IFN alpha 2c. Four patients were treated with human natural leukocyte interferon (HNLI). Interferon was applied locally. Historical control groups were used for comparison in the statistical analysis. The data were evaluated taking into account the single risk factor Clark levels III and IV. In the control group there were 10 patients with Clark levels III and IV; in the group of r.IFN apha 2c-treated patients there were 20 patients. The data were analyzed by using the Kaplan-Meier and Cox methods. Results. The percentage of survivals was higher in the interferon-treated groups with Clark levels III and IV, than in the control group, that is 60% compared to 25%, and 40% compared to 33%, respectively. The results of the statistical analysis after 60 months of follow-up are significantly better in the interferon group (P = 0.0175). Conclusions. The control group was not selected at random. Therefore, on the basis of our results, one can say that the treatment of the melanoma patients, Clark levels III and IV, with the r.IFN alpha 2c is promising and that further investigation is justified.  相似文献   
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To define the toxicity profile of recombinant human interleukin-6 (rhIL- 6) and to study its effect on hematopoiesis, biochemical parameters and other cytokines, rhIL-6 was administered in a phase I-II study to 20 patients with breast carcinoma or nonsmall cell lung cancer. RhIL-6 doses were 0.5, 1.0, 2.5, 5.0, 10, and 20 micrograms/kg/d, with at least three patients per dose level. RhIL-6 was administered 24 hours by continuous intravenous infusion followed by subcutaneous (SC) administration for 6 days, partly on an outpatient basis. RhIL-6- related side effects were fever, headache, myalgia, and local erythema. Starting at 2.5 micrograms/kg/d, these side effects were compounded by nausea, reversible increase in liver enzymes, and anemia. Flu-like symptoms were controllable up to and including 10 micrograms rhIL- 6/kg/d with acetaminophen. RhIL-6 increased platelet counts with a decrease in mean platelet volume and increased leukocytes caused by neutrophil, monocyte, and lymphocyte increase, with an increase in T cells and natural killer cells at 1.0 and 2.5 micrograms rhIL-6/kg/d. The reversible anemia was characterized by a decrease in serum iron, and an increase in ferritin and erythropoietin without reticulocytosis. RhIL-6 reduced total cholesterol levels and a dose-related increase of C-reactive protein and serum amyloid A plasma levels was observed. Serum IL-6 levels were increased, especially at 10 and 20 micrograms/kg/d, whereas no change in IL-1 beta and tumor necrosis factor alpha levels was observed. RhIL-6 can be administered with controllable side effects in this setting, up to and including a SC dose of 10 micrograms/kg/d on an outpatient basis, and has a promising stimulating effect on leukopoiesis and thrombopoiesis.  相似文献   
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Some physical concepts of laser-tissue interactions that occur in 308-nm excimer laser angioplasty are addressed. Monte Carlo numerical computations were used to analyze the light fluence rate distributions resulting from finite diameter laser beams incident on tissue, as applied by fiber-optic light delivery catheters. The fluence rate at the inside part of the tissue surface from a 0.2-mm diameter fiber emitting 308-nm light, is increased more than twice relative to the incident power density. The light fluence rate distribution inside the tissue spreads very little outside the incident beam diameter. Therefore, the distributions from different fibers in multifiber catheters will not overlap unless the fibers are very close together. The maximum fluence rate decreases with decreasing beam diameters. Ablation of tissue by a 308-nm excimer laser delivery system in contact with the tissue resulted in a damage zone adjacent to the crater wall, due to expansion of the gaseous debris trapped under the tip of delivery system. In case of contact irradiation, the ablation was more efficient than in case of noncontact irradiation. Direct temperature measurements during excimer laser ablation by an infared (IR) camera showed that temperature accumulation will occur when a sequence of pulses is applied at frequencies of at least 5 Hz. The temperature rise above ambient under circumstances simulating clinical conditions is measured to be 66°± 7°C.  相似文献   
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