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BACKGROUND: Psychotic symptoms in Alzheimer disease (AD+P) identify a heritable phenotype associated with more rapid cognitive decline. The authors have proposed that AD+P is itself a composite of a misidentification and a paranoid subtype with increased cognitive impairment restricted to the misidentification type. Most prior studies of the clinical correlates of AD+P have been limited, however, by the inclusion of prevalent cases. METHODS: Subjects with possible or probable AD or mild cognitive impairment (MCI) without psychosis at study entry were assessed at the time of initial presentation and then annually. Psychotic symptoms were assessed using the CERAD Behavioral Rating Scale. Survival analyses used Cox proportional hazard models with time-dependent covariates to examine the predictors of psychosis onset. RESULTS: A total of 288 subjects completed at least one follow-up examination. Mean duration of follow-up was 22.1 months. The incidence of psychosis was 0.19 per person-year. Cognitive impairment was associated with onset of psychosis, largely as a result of its association with onset of the misidentification, but not the paranoid, subtype. Including psychotropic medication use in the model revealed an association of antidepressant use with the onset of psychosis. This latter association appeared to arise from an underlying association between depression and the risk of psychosis onset rather than from antidepressant treatment. CONCLUSION: These findings are consistent with the hypothesis that the misidentification and the paranoid subtypes each define a more biologically homogeneous group than AD+P as a whole. Further exploration of the relationship between depressive symptoms and psychosis in patients with AD is warranted.  相似文献   
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Although there are effective antibacterial agents against plague, newer antibacterial agents have been developed which show more potent activity against other bacterial organisms, but have not been tested againstYersinia pestis. A strain ofYersinia pestis was selected (no. 22; National Institute of Infectious Diseases, Tokyo, Japan) that caused a systemic infection in mice.Y. pestis no. 22 was intraperitoneally inoculated into DDY-strain mice, and 13 oral or 6 injectable antibacterial drugs given to the infected mice at varying doses 1 and 24 hours after infection. Levofloxacin, sparfloxacin and ofloxacin were the most effective oral agents against the infection, and prulifloxacin and pazufloxacin were also effective but to a lesser extent. Also, gentamicin and arbekacin were the most potent injectable antibacterial agents againstY. pestis. These results suggest that there are several new drugs, both oral and injectable, which exert excellent in vivo antibacterial activity against a mouse infection model and may be useful for the clinical treatment of plague.  相似文献   
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OBJECTIVE: To evaluate a proposed technique for the 3-dimensional (3D) detection of hemangiomas, including vascular malformation and their feeding arteries, in the head and neck. The new technique combines phase-contrast magnetic resonance angiography (PCMRA) without contrast medium and 3D fast asymmetric spin-echo (FASE) sequences. METHODS: The technique was applied to 3 patients having hemangiomas in the head and neck region. In 1 patient the image obtained with the proposed technique was compared to that obtained by standard contrast angiography. RESULTS: In all 3 patients, the 3D presence of the hemangiomas and the feeding arteries were well defined in images created by the proposed technique. Additionally, the characterization of the hemangioma's 3D structure and distribution of the feeding arteries coincided with those observed using contrast angiography in the case for which contrast angiography was also performed. CONCLUSIONS: Preliminary experience shows that the proposed technique combining 3D-FASE and 3D-PCMRA is useful to visualize both the 3D structure of hemangiomas and to identify the 3D distribution of the feeding arteries without using contrast medium.  相似文献   
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iNKT cells are a unique subset of CD1-restricted T lymphocytes that express T cell receptor (TCR) and some NK receptors. iNKT cells express an invariant TCRalpha chain composed of Valpha14-Jalpha18 segments in mice and Valpha24-Jalpha18 segments in humans associated with TCRbeta chains using a restricted set of Vbeta. iNKT cells recognize glycolipid antigens such as alpha-galactosylceramide (alpha-GC) presented by CD1d, non-pormorphic MHC class I-like molecule, and rapidly secrete large amounts of cytokines including IL-4 and IFN-gamma upon activation. Due to its potent ability to produce a variety of cytokines, iNKT cells are involved in a various kinds of immunoregulation. iNKT cells play a regulatory role in some disease models such as type I diabetes in NOD mice. In contrast, iNKT cells exaggerate the pathogenesis such as arthritis, allergic airway inflammation and atherosclerosis. In addition, iNKT cells are an attractive target for immunotherapy because several different synthetic glycolipid antigens to modify the function of iNKT cells are available. In this review, we examine the potential roles of NKT cells in the pathogenesis of a variety of diseases including autoimmunity , allergy, infection and cancer. Additionally, we discuss on the recent advances in glycolipid therapy for these disease models.  相似文献   
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To elucidate the significance of angiotensin II (AID-induced hypertension chemotherapy, changes of tissue blood flow both in normal subcutis and in tumors (AH109A, LY80) were measured with the hydrogen gas clearance method. A newly-developed anesthetic machine was used to keep the animals' condition constant. Tissue blood flow in normal subcutis and tumors always fluctuated with time under normotension. The nature and the rate of fluctuation in tumor Wood flow were almost identical in two different types of tumors. However, the fluctuation of blood flow in tumor and that in normal subcutis were almost always inversely related when blood flows in these different tissues were measured simultaneously, i.e., when tissue blood flow in normal subcutis decreased, tumor blood flow increased, and vice versa. The findings supported the idea that the connection mode between the tumor vascular bed and normal vascular bed is a parallel circuit. Vascular resistance in the normal vascular bed under All-induced hypertension seemed to be greater than that under normotension, because the All-increased tumor blood flow always exceeded the maximum tumor blood flow under normotension. Due to the fluctuations of tumor blood flow, no-flow or low-flow areas, resistant to delivery of anti-cancer drugs, moved sporadically within the tumor under the normotensive condition. However, good conditions for drug delivery to tumor tissue were induced by All-induced hypertension.  相似文献   
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