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71.
Polymyositis (PM) is an autoimmune inflammatory muscle disease of unknown cause in which cellular immunity is thought to play an important pathogenic role. Class II major histocompatibility complex (class II MHC: human leukocyte antigen (HLA)-DR operates as a cofactor of antigen presentation in immunological responses. There has been a major debate over whether muscle fibers themselves synthesize and express HLA-DR molecules and play a role in antigen presentation in PM pathogenesis. In this study, we demonstrated that most muscle fibers from patients with PM synthesized and expressed HLA-DR molecules on their surface. Human leukocyte antigen-DR expression was highly specific to PM. In addition, class II transactivator (CIITA), human leukocyte antigen DM (HLA-DM), and invariant chain (Ii), which are indispensable for expression of mature HLA-DR molecules and for antigen processing and presentation, were co-expressed. One of the cytokines that could induce this expression is interferon-gamma (IFN-gamma), released by activated lymphocytes. Our results indicate that in PM muscle fibers synthesize and express HLA-DR molecules and may contribute to the inflammatory responses together with lymphocytes.  相似文献   
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An autopsy case with clinically and molecular genetically diagnosed Huntington's disease (HD) accompanied with minimal non-specific neuropathological features was reported. When the patient was 45 years old, he had faulty memory, mood swing, personality change and agitation. Neurological and psychiatric examinations revealed choreoathetoid movements in limbs and trunk, generalized hyperreflexia and mental deterioration. However, cerebellar ataxia and muscle rigidity were not disclosed. Neuroimaging study did not show a definite atrophy of heads of caudate nuclei. Neuroacanthocytosis and Wilson's disease were ruled out by the peripheral blood examination and serum Cu and ceruloplasmin examination. At the age of 55 he died of pneumonia. Post-mortem examination revealed minimal non-specific neuropathological features for HD (Vonsattel's grade 0), that is, no visible fibrillary gliosis in the striatum, and few neuronal loss and only proliferation of astrocytes (astrocytosis) in the striatum. Molecular-genetic study the patient's brain tissues and his youngest son's blood was performed. These studies revealed 40 CAG repeats in the patient, 56 CAG repeats in his youngest son. These results suggest they may be HD. Vonsattel et al. [ 1998] insist that grade 0 comprises 1% of all HD brains, and grade 1 comprises 4% of all HD brains. But we could not find any reports in which the clinical and neuropathological features were described in detail on the cases with clinically and molecular genetically diagnosed HD without specific pathological findings. Therefore, we present in detail the clinical and neuropathological features of such case.  相似文献   
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To update the evidence on the association between smoking and mortality, we analyzed data from a population-based prospective study in Japan. In total, 19950 men and 21534 women aged 40 - 59 who reported their smoking history and had no serious disease at baseline survey were followed. During 1990 - 1999, 1014 men and 500 women died. Smokers were associated with an unhealthy lifestyle. Relative risks (RRs) for selected cause of death due to smoking were slightly attenuated by adjusting for possible confounding factors. Age- and area-adjusted RRs of male current smokers compared with never smokers were 1.66 (95% confidence intervals (CI): 1.40, 1.95) for all causes, 1.69 (1.31, 2.18) for all cancers, 1.67 (1.20, 2.34) for all circulatory system disease, and 1.63 (1.24, 2.15) for other causes, while those of females were 2.03 (1.52, 2.73), 2.06 (1.35, 3.15), 2.99 (1.75, 5.11), 1.31 (0.69, 2.51), respectively. After adjusting for multivariate variables, the corresponding RRs of male smokers were 1.55 (1.29, 1.86), 1.61 (1.20, 2.15), 1.41 (0.97, 2.03), and 1.61 (1.17, 2.19), against 1.89 (1.36, 2.62), 1.83 (1.14, 2.95), 2.72 (1.45, 5.07), and 1.39 (0.71, 2.73) for females. Twenty-two percent of death from all causes, 25% of all cancer, and 17% of all circulatory system disease deaths, could be attributed to cigarette smoking in males, and 5%, 4%, and 11% in females, respectively. Cumulative dose as indicated by pack-years was clearly associated with cancer death. These findings provided information as to the quantitative risk for premature death due to smoking among middle-aged Japanese men and women, and showed that the elevated risk was not explained by the unhealthy lifestyle of smokers.  相似文献   
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J Takeuchi  M Sobue  M Yoshida  E Sato 《Cancer》1978,42(1):202-208
An analysis was carried out on glycosaminoglycan produced in pleomorphic adenoma, adenoid cystic carcinoma, sialadenitis and normal tissue of the salivary gland. After incubation of the tissue segments in a medium containing 35SO4, a radioautograph of the tissue section was made to observe the localization of 35SO4 incorporation, and 35S-labelled materials were purified from the tissues, and analyzed. High 35S-radioactivity was observed in the ductal cells of the inflammatory gland tissue and in the acinar cells of normal palatinal gland, but little radioactivity was observed in the interstitial components in these tissues, and the amount of 35SO4 incorporated in the tumor cells was also significant. Eighty to 90% of the 35S-radioactivity incorporated could be detected as 35S-glycosaminoglycans in all tissues except for the normal palatinal gland, which contained a large amount of 35S-sulfated glycoprotein. No significant difference in the synthetic activity of 35S-glycosaminoglycans and in their components were observed between nonneoplastic and neoplastic cells. These results suggest that glycosaminoglycan-producing cells in pleomorphic adenoma as well as in adenoid cystic carcinoma are derived from the tubuloacinar cells of the salivary gland.  相似文献   
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