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71.
PURPOSE: The aim of this study was to determine whether collagen XVIII expression is correlated with circulating serum endostatin and whether this has any prognostic value in patients with non-small cell lung cancer (NSCLC). EXPERIMENTAL DESIGN: Serum endostatin levels were measured quantitatively by a competitive enzyme immunoassay, and collagen XVIII expression in tumor tissue was investigated with an immunohistochemical method in a series of 94 patients who underwent surgery for NSCLC. RESULTS: Sixty cases (63.8%) had positive immunohistochemical staining with anticollagen XVIII polyclonal antibodies, including strongly positive staining in 11 (11.7%) cases. The mean (+/- SD) serum endostatin level was 41.6 +/- 34.4 ng/ml in the patient group and 16.3 +/- 10.3 ng/ml in the control group (P < 0.0001). The 11 cases who were strongly collagen XVIII-positive had significantly higher serum endostatin levels than the cases who were negative or weakly positive (P = 0.0297). The 5-year survival rates of negative, weakly positive, and strongly positive patients were 77.8%, 56.9%, and 43.8%, respectively. The cases with strongly positive collagen XVIII expression had a significantly poorer outcome than cases with negative expression (P = 0.0027). A multivariate analysis with Cox proportional hazards model for disease-specific survival revealed that expression of collagen XVIII (strongly positive versus negative; weakly positive versus negative), tumor classification, and regional lymph node classification were independent prognostic factors. CONCLUSIONS: Our results suggest that expression of collagen XVIII in tumor tissue is strongly associated with a poorer outcome in NSCLC and correlates with elevated levels of circulating serum endostatin.  相似文献   
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Background This retrospective study analyzed the outcome in patients with intracranial germ-cell tumors to determine whether tumor response during radiation therapy can predict achievement of primary local control with radiation therapy alone. Methods Between 1983 and 1993, 22 patients with untreated primary intracranial germ cell tumors received a total whole brain radiation dose of between 18 Gy and 45 Gy (mean 31.3 Gy) with or without a localized field of 10 to 36.4 Gy (mean, 22.4 Gy), or local irradiation only (1 patient). In 10 patients with pineal tumor only, who were treated first with radiation therapy, tumor response to radiation therapy was evaluated using computed tomography (CT) (at baseline, and approximately 20 Gy and 50 Gy). Areas of calcification in the tumor were subtracted from total tumor volume. Follow-up time ranged from 2 to 12 years. Results Five-year actuarial survival rates for patients with germinoma were 71%, 100% for patients with a teratoma component, and 100% for patients without histologic verification. Patients with germinomas or tumors suspected of being germinomas who were given more than 50 Gy had no local relapse. There was no correlation between primary local control by radiation therapy alone and initial tumor volume. The rate of tumor volume response to irradiation assesed by CT was significantly different in those patients who relapsed compared to those who did not relapse Conclusion Tumor response during radiation therapy using CT was considered to be predictive of primary local control with radiation therapy alone.  相似文献   
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A 72-year-old Japanese woman, suffering from squamous cell lung cancer with brain metastasis, underwent 2 courses of combination chemotherapy, consisting of cisplatin and vindesine. Although both the primary tumor and the brain metastasis regressed markedly, she developed left ocular pain with blurred vision. An abnormal mass was found in the left iris, and cytologic examination of the aqueous aspirate revealed a few malignant cells, which, when examined by electron microscopy, were considered to be derived from squamous cell carcinoma of the lung.  相似文献   
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Induction of antitumor immunity to T-9 rat glioma by intracellular hyperthermia using functional magnetic particles was investigated. Magnetite cationic liposomes (MCLs), which have a positive surface charge, were used as heating mediators for intracellular hyperthermia. Solid T-9 glioma tissues were formed subcutaneously on both femurs of female F344 rats, and MCLs were injected via a needle only into the left solid tumors (treatment side). The rats were then divided into two groups, which received no irradiation, or irradiation for 30 min given three times at 24-h intervals with an alternating magnetic field (118 kHz, 384 Oe). On the treatment side, the tumor tissue disappeared completely in many rats exposed to the magnetic field. The tumor tissue on the opposite side also disappeared completely, even though MCLs were not injected into the right solid tumors. To examine whether a long-lasting and tumor-specific immunity could be generated, the rats that had been cured by the hyperthermia treatment were rechallenged with T-9 cells 3 months later. After a period of transient growth, all tumors disappeared. Furthermore, immuno-cytochemical assay revealed that the immune response induced by the hyperthermia treatment was mediated by both CD8+ and CD4+ T cells and accompanied by a marked augmentation of tumor-selective cytotoxic T lymphocyte activity. These results suggest that our magnetic particles are potentially effective tools for hyperthermic treatment of solid tumors, because in addition to killing of the tumor cells by heat, a host immune response is induced.  相似文献   
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Two new 6,6-spiroacetal polyketides, spirotoamides A (1) and B (2), were isolated from a microbial metabolite fraction library of Streptomyces griseochromogenes JC82-1223 by screening of structurally unique compounds based on a search of spectral database. The fraction library was constructed using a systematic separation method to efficiently discover new metabolites from microbial sources such as actinomycetes and fungi. The structures of 1 and 2 were elucidated by 2D-NMR and mass spectrometric measurements. They belong to a class of polyketides, and contain a 6,6-spiroacetal core structure and a carboxamide group. The biosynthetic pathway of 1 and 2 is discussed in the text.  相似文献   
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