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Chondrosarcoma is the second most common primary malignant bone tumor. In this multicenter study, we sought to evaluate the disease‐specific survival (DSS) and disease‐free survival (DFS), and prognostic factors in patients with dedifferentiated chondrosarcoma (DDCS) or grade 3 chondrosarcoma (G3CS) in Japan. We retrospectively investigated the treatment outcomes and prognostic factors in 62 patients with DDCS and 19 patients with G3CS at 15 institutions participating in the Japanese Musculoskeletal Oncology Group. We also clarified significant clinicopathological factors for oncological outcomes. In surgery for primary lesions aimed at cure, a histologically negative margin (R0) was obtained in 93% (14/15) of patients with G3CS and 100% (49/49) of patients with DDCS. The 5‐year DSS was 18.5% in patients with DDCS and 41.7% in patients with G3CS (p = 0.13). Local control was obtained in 80% (12/15) and 79.6% (39/49) of patients with G3CS and DDCS in the primary lesion after surgery with a wide surgical margin, respectively. In multivariate analysis, stage and no treatment/palliative treatment for the primary lesion were independent prognostic factors for DSS of DDCS, and age and no treatment/palliative treatment for DSS of G3CS. The 5‐year DFS rate was 22.8% in 26 patients with DDCS who did not receive adjuvant chemotherapy, and 21.4% in 14 patients who received adjuvant chemotherapy. The prognosis of DDCS remains poor, although R0 resection was carried out in most cases. Effective and/or intensive chemotherapeutic regimens or agents should be considered or developed for patients with high‐grade chondrosarcoma, particularly for those with DDCS.  相似文献   
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IntroductionNonalcoholic fatty liver disease (NAFLD) is diagnosed after excluding other liver diseases. The pathogenesis of NAFLD when complicated by other liver diseases has not been established completely. Metabolic dysfunction‐associated fatty liver disease (MAFLD) involves more metabolic factors than NAFLD, regardless of complications with other diseases. This study aimed to clarify the effects of fatty liver occurring with metabolic disorders, such as MAFLD without diabetes mellitus (DM), on the development of DM.Materials and MethodsWe retrospectively assessed 9,459 participants who underwent two or more annual health check‐ups. The participants were divided into the MAFLD group (fatty liver disease with overweight/obesity or non‐overweight/obesity complicated by metabolic disorders), simple fatty liver group (fatty liver disease other than MAFLD group), metabolic disorder group (metabolic disorder without fatty liver disease), and normal group (all other participants).ResultsThe DM onset rates in the normal, simple fatty liver, metabolic disorder, and MAFLD groups were 0.51, 1.85, 2.52, and 7.36%, respectively. In the multivariate analysis, the MAFLD group showed a significantly higher risk of DM onset compared with other three groups (P < 0.01). Additionally, the risk of DM onset was significantly increased in fatty liver disease with overweight/obesity or pre‐diabetes (P < 0.01).ConclusionsFatty liver with metabolic disorders, such as MAFLD, can be used to identify patients with fatty liver disease who are at high risk of developing DM. Additionally, patients with fatty liver disease complicated with overweight/obesity or prediabetes are at an increased risk of DM onset and should receive more attention.  相似文献   
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In this study, the degradates generated from a pharmaceutical solid were characterized, and a mechanistic pathway underlying their formation was proposed. The chemical stability of a novel triazole antifungal drug, CS‐758, deteriorated significantly when the crystal was disordered, and characteristic degradates were generated. A total of eight degradates in solution and nine degradates in a solid state were isolated by preparative liquid chromatography. Degradates were characterized using high‐performance liquid chromatography–photodiode array, mass spectrometry, and nuclear magnetic resonance. Radical‐mediated oxidation is proposed as the main degradation pathway in the solid state. The initiation step of this pathway is hydrogen atom abstraction from a methine carbon that is adjacent to a dien moiety and the formation of a delocalized vinylic radical intermediate. Molecular oxygen is then added to the radical position to form hydroperoxides. There are three potential oxidation routes based on the proposed autoxidation pathway that lead to the generation of the dioxane ring‐opening hydroxyl form, the 9,10‐epoxide form, or the 11,12‐epoxide form, depending on the substituted position of the added molecular oxygen. The epimer compound generated via the vinylic radical intermediate and sulfoxides was characterized. This degradation mechanism provides the scientific foundation for an oxidative stressing system currently under investigation.  相似文献   
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