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91.
Stereotactic radiosurgery for body tumors is hampered by the difficulties in body fixation and respiratory motions of the tumor. We have developed a Microton-based system for the stereotactic irradiation of body tumors, which delivers radiation at a predetermined respiratory phase. The patients are fixed non-invasively in the custom-made bed, and CT images are obtained. The isocentor is calculated with reference to those images and is marked onto the patient's skin and the custom-made bed. The patient lying on the bed is transferred to the treatment couch of the Microtoron. After reproducing the isocenter, actual treatment is started. The treatment couch as well as the gantry move automatically around the isocenter according to the treatment planning. The circular collimator moves by computer control to reduce geometrical errors to less than 0.5 mm, which is evoked by gantry movement. Respiratory movement of the abdominal wall is measured by laser displacement monitor. The Microtron delivers X-rays at a predetermined respiratory phase with a lag time of 20 msec after the on-signal from the monitor.  相似文献   
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We measured the levels of soluble interleukin-2 receptor (sIL-2R) in the serum of 53 patients with hematological malignancies (14 with acute leukemia, 10 myeloproliferative disorders, 21 non-Hodgkin's lymphoma and 8 multiple myeloma), 40 with non-hematological solid malignancies (24 with lung cancer, 11 digestive system cancer and 5 other cancers) and 95 healthy subjects as a control using an enzyme-linked immunosorbent assay. Both hematological and non-hematological neoplasms showed significantly higher sIL-2R levels than normal subjects (p<0.01). However, compared to solid malignancies, hematological neoplasms displayed a wide range of sIL-2R levels and extremely elevated values of sIL-2R were seen in certain cases. These results seem to suggest that sIL-2R levels may serve as one of non-invasive markers of differential diagnosis for patients with bulky mass lesions between hematological and solid malignancy.  相似文献   
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This retrospective study was conducted to assess the safety, efficacy, and long-term results of multi-modality therapy including radio-frequency thermal ablation (RFA) and radiotherapy as an additional cytoreductive method for eliciting the marked effects of chemotherapy in treating unresectable lung metastases from colorectal cancer. Total of 21 patients with lung metastasis from colorectal cancer were included. They were treated with modified pharmacokinetic modulating chemotherapy (PMC). Eleven were also treated with RFA and/or radiotherapy (multi-modality group), and 10 were treated with chemotherapy alone (chemotherapy group). Characteristics and survival of patients in the multi-modality group were compared with those of the chemotherapy group. The median survival of all patients was 38.6 months after the initial PMC. The cumulative 3-year survival rate of patients in the multi-modality group was 87.5% compared with 33.3% in the chemotherapy group (p=0.0041). The course of multi-modality therapy was uneventful except for pneumothorax in those who received RFA. Although pneumothorax developed in 4 of 11 patients (36.4%) treated with RFA, all were able to receive chemotherapy within 2 weeks after RFA. In conclusion, multi-modality therapy combined with modified PMC, radiation and RFA is a feasible choice of treatment associated with reasonable morbidity and mortality in patients with inoperable lung metastases from colorectal cancer.  相似文献   
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Syndecans are single-pass integral membrane components that serve as co-receptors for growth factors and cytokines and can elicit signal transduction via their cytoplasmic tails. We review here previous studies from our groups on syndecan-3 biology and function in the growth plates of developing long bones in chick and mouse embryos. Gain- and loss-of-function data indicate that syndecan-3 has important roles in restricting mitotic activity to the proliferative zone of growth plate and may do so in close cooperation and interaction with the signaling molecule Indian hedgehog (IHH). Biochemical and protein-modeling data suggest a dimeric/oligomeric syndecan-3 configuration on the chondrocytes cell surface. Analyses of embryos misexpressing syndecan-3 or lacking IHH provide further clues on syndecan-3/IHH interdependence and interrelationships. The data and the conclusions reached provide insights into mechanisms fine-tuning chondrocyte proliferation, maturation, and function in the developing and growing skeleton and into how abnormalities in these fundamental mechanisms may subtend human congenital pathologies, including osteochondromas in hereditary multiple exostoses syndrome.  相似文献   
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BACKGROUND: Extracapsular spread of lymph node metastasis has been shown as a negative prognostic factor in cancers of several other organs. This study was performed to clarify the prognostic significance of extracapsular spread in patients receiving curative resection for gastric cancer. METHODS: Extracapsular spread was defined as infiltration of cancer cells beyond the capsule of the metastatic lymph node. Four hundred and two patients who underwent curative gastrectomy were evaluated. Eight potential prognostic factors, including the International Union Against Cancer (Union International Contra la Cancrum; [UICC]) N stage and nodal status classified by the presence of lymph node metastasis or extracapsular spread, were examined. RESULTS: Three survival curves grouped by nodal status differed significantly, and prognosis of patients with extracapsular spread was significantly worse than for the other groups. Both UICC N stage ( P < .001) and nodal status ( P < .001) were significant prognostic factors by multivariate analysis. UICC N stages were subcategorized by nodal status, and survival was shown to be significantly worse in patients with extracapsular spread in the UICC N1 group ( P = .04). CONCLUSIONS: Extracapsular spread was a significant negative prognostic indicator on multivariate analysis, and may be useful in combination with UICC N stage. Extracapsular spread was regarded as an important indicator to refine the nodal staging system in gastric cancer.  相似文献   
100.
Although the antioxidant properties of green, oolong, and black teas have been well studied, antioxidant activity has not been examined in roasted tea. Therefore, in the current studies, we investigated the antioxidant activity of roasted tea in comparison with those of green, oolong, and black teas. Using water extracts of the various teas, we examined the total phenolic content as well as the antioxidant activities, including the reducing power, the 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity, and the inhibition of hemolysis caused by 2,2'-azo-bis(2-amidinopropane) dihydrochloride (AAPH)-induced lipid oxidation in erythrocyte membranes. The roasted tea contained lower levels of total phenolics than green, oolong, or black tea (green tea > oolong tea > black tea > roasted tea). The relative reducing power and DPPH scavenging activity decreased in the following order: green tea > roasted tea > oolong tea > black tea. Also, green tea was more effective against AAPH-induced erythrocyte hemolysis than other teas (green tea>roasted tea = oolong tea = black tea). These results suggest that roasted tea is beneficial to health, in humans, because of its high antioxidant activity.  相似文献   
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