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991.
The aim of the present study was to confirm the histopathological features of aggressive B-cell lymphoma in Papua New Guinea (PNG)-an EBV endemic region. The immunophenotypic features and expression of EBV-encoded proteins and RNA in B-cell lymphomas were analyzed in 21 PNG children, and compared to the corresponding features of 17 Japanese children with Burkitt lymphoma (BL). Histological diagnosis of the lymphomas from the PNG children was BL in nine patients; atypical Burkitt/Burkitt-like variant of BL (BLL) in three; diffuse large B-cell lymphoma (DLBCL) in four; and B-lymphoblastic lymphoma (B-LBL) in five. The lymphomas from the PNG children had a high positive rate on EBV-RNA in situ hybridization (EBV-ISH; 66.7%). With regard to the histological typing, 10 of 12 patients (83%) with BL/BLL, one of four (25%) with DLBCL, and three of five (60%) with B-LBL were positive for EBV-ISH. The findings of EBV-positive B-LBL were surprising because it is commonly considered that lymphoblastic lymphoma is not associated with EBV. EBV positivity was not detected in the 12 Japanese patients who were available for the EBV-ISH evaluation. It is concluded that it is possible that a proportion of DLBCL and B-LBL besides BL/BLL are associated with EBV in endemic region.  相似文献   
992.
Neural stem cells (NSCs) have attracted considerable attention as a potential source of cells for therapeutic treatment of impaired areas of the central nervous system. However, efficient and clinically feasible strategies for expansion of the endogenous NSC pool are currently unavailable. In this study, we demonstrate that mood stabilizing drugs, which are used to treat patients with bipolar disorder, enhance the self-renewal capability of mouse NSCs in vitro and that this enhancement is achieved at therapeutically relevant concentrations in the cerebrospinal fluid. The pharmacological effects are mediated by the activation of Notch signaling in the NSC. Treatment with mood stabilizers increased an active form of Notch receptor and upregulated its target genes in neural stem/progenitor cells, whereas coculture with gamma-secretase inhibitor or the presence of mutation in the presenilin1 gene blocked the effects of mood stabilizers. In addition, chronic administration of mood stabilizers expanded the NSC pool in the adult brain, which subsequently increased the cell supply to the olfactory bulb. We suggest that treatment with mood stabilizing drugs could be used to facilitate regeneration following insult to the central nervous system.  相似文献   
993.
In this review, recent changes in both treatments and outcomes of rheumatoid arthritis (RA) in Japan were analyzed by viewing the National Database of Rheumatic Diseases by iR-net, one of the largest clinical databases for RA patients in Japan. Regarding drug therapy, the use of methotrexate has been continuously increasing and has established a place as an anchor drug in the treatment of RA among other nonbiologic disease-modifying antirheumatic drugs; however, the dosage used is still significantly less compared with that of western countries. In addition to methotrexate, the use of tacrolimus has increased gradually. The most prominent observed change is a rapid increase in the use of biologics, which rose to stardom in the treatment of RA in Japan and western countries. These changes in drug therapy could allow us to control RA disease activity more tightly. In line with this, the outcomes of patients with RA in Japan have been improving continuously, both clinically and functionally. Subsequently, the use of both NSAIDs and corticosteroids has decreased. In addition, overall rates of joint operations related to RA have also decreased; in particular, a significant decrease was noticed in the incidence of joint replacement and synovectomy. Overall, the trends in treatments and subsequent outcomes for RA in Japan have exactly followed those seen in western countries.  相似文献   
994.
Bat coronavirus (BtCoV) is assumed to be a progenitor of severe acute respiratory syndrome (SARS)-related coronaviruses. To explore the distribution of BtCoVs in the Philippines, we collected 179 bats and detected viral RNA from intestinal or fecal samples by RT-PCR. The overall prevalence of BtCoVs among bats was 29.6?%. Phylogenetic analysis of the partial RNA-dependent RNA polymerase gene suggested that one of the detected BtCoVs was a novel alphacoronavirus, while the others belonged to the genus Betacoronavirus. Western blotting revealed that 66.5?% of bat sera had antibodies to BtCoV. These surveys suggested the endemic presence of BtCoVs in the Philippines.  相似文献   
995.
This research focused on both the psychological benefits and costs of crying. We investigated the relationships of intrapersonal and interpersonal consequences of crying. Female nurses (N = 300) were requested to describe one of the most impressive negative episodes where they had cried. Then, they were asked to complete a questionnaire including a scale of their psychological changes after the crying episode and the social reactions when they cried. Factor analysis revealed five components of the psychological changes scale. Solitary crying had greater effects for both psychological benefits and costs after crying than crying in front of others. Factor analysis revealed three components of the scale of social reactions. When they cried in front of others, "catharsis", "positive attitude", and "recognition of the relationship with others" after crying were associated with "empathy and social support" from others. The factors of "recognition of negative reality" and "negative attitude" were associated with "criticism and slander" from others. These results were discussed in terms of the communicative functions and the reflective functions of adult crying.  相似文献   
996.
Bats have great potential as reservoirs for emerging viruses such as severe acute respiratory syndrome-coronavirus. In this study, bat coronaviruses (BtCoVs) were detected by RT-PCR from intestinal and fecal specimens of Miniopterus fuliginosus breeding colonies in Wakayama Prefecture caves, where we previously identified bat betaherpesvirus 2. Two primer sets were used for the detection of BtCoV: one was for the RNA-dependent RNA polymerase (RdRp) region and the other was for the spike (S) protein region. Eleven and 73% of intestinal and fecal specimens, respectively, were positive for RdRp region, and 2 and 40% of those were positive for S protein region. Sequencing and phylogenetic analysis showed that the detected BtCoV belonged to the group 1 (alpha) coronaviruses. These data suggest that BtCoV is endemic in M. fuliginosus in Japan.  相似文献   
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