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1.
We studied 14 patients with obsessive-compulsive disorder (OCD) by positron emission tomography and the fluorodeoxyglucose method, looking for abnormalities in local cerebral metabolic rates for glucose in brain structures that have been hypothesized to function abnormally in OCD. These patients were compared with 14 normal controls and 14 patients with unipolar depression. The patients with unipolar depression and OCD did not differ in levels of anxiety, tension, or depression. In OCD, metabolic rates were significantly increased in the left orbital gyrus and bilaterally in the caudate nuclei. This was apparent on all statistical comparisons with both controls and unipolar depression. The right orbital gyrus showed at least a trend to an increased metabolic rate in all comparisons. The metabolic rate in the left orbital gyrus, relative to that in the ipsilateral hemisphere (orbital gyrus/hemisphere ratio), was significantly elevated compared to controls and subjects with unipolar depression, and stayed high even with successful drug treatment. Though it was in the normal range in the morbid state, with improvement in OCD symptoms after drug treatment, the caudate/hemisphere metabolic ratio increased uniformly and significantly bilaterally. This ratio did not increase in patients who did not respond to treatment. Thus, OCD showed cerebral glucose metabolic patterns that differed from controls in both the symptomatic and recovered states.  相似文献   
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In recent years, research on the aetiology of psoriasis has focused on immune aetiopathogenesis. However, in the last few years, research on the immunoloogical changes in psoriasis has failed to mention the lymphatics. Also, studies emphasizing the importance of the dermal lymphatics have neglected the lymphatic changes seen in psoriasis. Therefore, we decided to put this matter back on the agenda. Skin biopsies from 20 patients with psoriasis vulgaris were examined lymphatically by light microscopy using the orcein stain. We found a considerable increase in both number and dilatation in the lymphatics of psoriatic plaques, compared with both the clinically uninvolved skin of the psoriatic patients and also the skin of the control group.  相似文献   
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We show here that T cell cross-reactivity between heterologous viruses influences the immunodominance of virus-specific CD8(+) T cells by two mechanisms. First, T cells specific for cross-reactive epitopes dominate acute responses to viral infections; second, within the memory pool, T cells specific for cross-reactive epitopes are maintained while those specific for non-cross-reactive epitopes are selectively lost. These findings suggest an immunological paradigm in which viral infections shape the available T cell repertoire, causing alterations in the hierarchies of both the primary and memory CD8(+) T cell responses elicited by subsequent viral infections. Thus, immunodominance is a function of the host's previous exposure to unrelated pathogens, and this may have an impact on protective immunity and immunopathology.  相似文献   
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Abstract

Synthetic micro/nanomotors (MNMs) are novel, self-propelled nano or microscale devices that are widely used in drug transport, cell stimulation and isolation, bio-imaging, diagnostic and monitoring, sensing, photocatalysis and environmental remediation. Various preparation methods and propulsion mechanisms make MNMs “tailormade” nanosystems for the intended purpose or use. As the one of the newest members of nano carriers, MNMs open a new perspective especially for rapid drug transport and gene delivery. Although there exists limited number of in-vivo studies for drug delivery purposes, existence of in-vitro supportive data strongly encourages researchers to move on in this field and benefit from the manoeuvre capability of these novel systems. In this article, we reviewed the preparation and propulsion mechanisms of nanomotors in various fields with special attention to drug delivery systems.  相似文献   
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Inhibition of the proteasome has emerged as a clinically effective anticancer therapeutic approach in recent years. Bortezomib (Velcade®) showed extremely high potency against a wide range of cancer cell lines. Ixazomib (MLN9708-MLN2238), the second-generation proteasome inhibitor, selectivity and potency were similar to that of bortezomib, is currently being investigated in phase I studies. It shows superior antitumor activity in hematologic malignancy, especially multiple myelomas. In this study, for the first time, we evaluated and compared the antiproliferative and apoptotic effects of the novel proteasome inhibitor MLN2238 (the active form of MLN9708) with bortezomib using in vitro chronic myeloid leukemia. Cytotoxic and apoptotic effects of MLN2238 and bortezomib were determined by trypan blue dye exclusion assays, WST-1 cell proliferation assay, increased AnnexinV-PI binding capacity, changes in caspase-3 activity and loss of mitochondrial membrane potential (JC-1). Associated with proteasome pathway NFκB1 and c-myc mRNA expression levels were examined by the qRT-PCR method. We observed that cytotoxic and apoptotic effects on K562 cells were started at 5?μm of MLN2238 and 1?μm of bortezomib after 24 and 48?h. Also, MLN2238 and bortezomib downregulated NFκB1 and c-myc mRNA expression at 24?h. Our result revealed that MLN22238 and bortezomib had significant cytotoxic and apoptotic effects on K562 cells. Here, we first demonstrate in vitro data that support the development of MLN2238, by direct comparison with bortezomib on K562 cells.  相似文献   
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