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Nasopharyngeal carcinoma (NPC) is originated from the epithelial cells of nasopharynx, Epstein–Barr virus (EBV)-associated and has the highest incidence and mortality rates in Southeast Asia. Late presentation is a common issue and early detection could be the key to reduce the disease burden. Sensitivity of plasma EBV DNA, an established NPC biomarker, for Stage I NPC is controversial. Most newly reported NPC biomarkers have neither been externally validated nor compared to the established ones. This causes difficulty in planning for cost-effective early detection strategies. Our study systematically evaluated six established and four new biomarkers in NPC cases, population controls and hospital controls. We showed that BamHI-W 76 bp remains the most sensitive plasma biomarker, with 96.7% (29/30), 96.7% (58/60) and 97.4% (226/232) sensitivity to detect Stage I, early stage and all NPC, respectively. Its specificity was 94.2% (113/120) against population controls and 90.4% (113/125) against hospital controls. Diagnostic accuracy of BamHI-W 121 bp and ebv-miR-BART7-3p were validated. Hsa-miR-29a-3p and hsa-miR-103a-3p were not, possibly due to lower number of advanced stage NPC cases included in this subset. Decision tree modeling suggested that combination of BamHI-W 76 bp and VCA IgA or EA IgG may increase the specificity or sensitivity to detect NPC. EBNA1 99 bp could identify NPC patients with poor prognosis in early and advanced stage NPC. Our findings provided evidence for improvement in NPC screening strategies, covering considerations of opportunistic screening, combining biomarkers to increase sensitivity or specificity and testing biomarkers from single sampled specimen to avoid logistic problems of resampling.  相似文献   
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常规免疫组织化学(immunohistochemistry,IHC)是组织病理学中广泛应用的诊断技术.但该技术存在诸多局限性,包括观察者间的变异性高,每张组织切片仅能标记一个标志物.本文详细描述了各种多重检测技术,这些技术克服了上述局限性,可在单张切片上同时检测多个标志物,可对细胞组成、细胞功能和细胞间相互作用进行整合...  相似文献   
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Recurrent loss-of-function mutations of spliceosome gene, ZRSR2, occur in myelodysplastic syndromes (MDS). Mutation/loss of ZRSR2 in human myeloid cells primarily causes impaired splicing of the U12-type introns. In order to further investigate the role of this splice factor in RNA splicing and hematopoietic development, we generated mice lacking ZRSR2. Unexpectedly, Zrsr2-deficient mice developed normal hematopoiesis with no abnormalities in myeloid differentiation evident in either young or ≥1-year old knockout mice. Repopulation ability of Zrsr2-deficient hematopoietic stem cells was also unaffected in both competitive and non-competitive reconstitution assays. Myeloid progenitors lacking ZRSR2 exhibited mis-splicing of U12-type introns, however, this phenotype was moderate compared to the ZRSR2-deficient human cells. Our investigations revealed that a closely related homolog, Zrsr1, expressed in the murine hematopoietic cells, but not in human cells contributes to splicing of U12-type introns. Depletion of Zrsr1 in Zrsr2 KO myeloid cells exacerbated retention of the U12-type introns, thus highlighting a collective role of ZRSR1 and ZRSR2 in murine U12-spliceosome. We also demonstrate that aberrant retention of U12-type introns of MAPK9 and MAPK14 leads to their reduced protein expression. Overall, our findings highlight that both ZRSR1 and ZRSR2 are functional components of the murine U12-spliceosome, and depletion of both proteins is required to accurately model ZRSR2-mutant MDS in mice.  相似文献   
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目的:比较鞘内注射孤啡肽在Swiss albino和C57BL两种小鼠中所引发的痛觉超敏的特点。方法:以随机、双盲、画笔轻触法,观察鞘内注射孤啡肽50min内两种小鼠痛觉超敏反应。结果:在Swiss albino小鼠中,孤啡肽引起的痛觉超敏持续50min,在5fmol--50pmol的剂量范围内,没有观察到量效关系。在C57BL小鼠中,孤啡肽引起的痛觉超敏持续30min,在10fmol~1nmol的剂量范围内,呈现出钟形的量效曲线。结论:鞘内注射孤啡肽的作用有小鼠种系间的区别。  相似文献   
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Asia is a large continent and there is significant diversity between countries and regions. Over the last 30 years, absolute blood pressure (BP) levels in Asia have increased to a greater extent than those in other regions. In diverse Asia‐Pacific populations, for choosing an Asia‐specific approach to hypertension management is important to prevent target organ damage and cardiovascular diseases. In this consensus document of HOPE Asia Network, we introduce seven action approaches for management of hypertension in Asia.  相似文献   
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The aim of this study was to determine if the following characteristics were associated with the presence of psoriatic arthritis in a sample of psoriasis patients: race, family history of psoriasis and psoriatic arthritis, age of onset of psoriasis, smoking, alcohol consumption and the maximum body surface area (BSA) affected by psoriasis. This was a case–control study involving 400 psoriasis patients who attended the Psoriasis and Photo‐medicine clinic in the National Skin Center of Singapore over a 1‐year period. Cases were psoriasis patients with psoriatic arthritis while controls were psoriasis patients without psoriatic arthritis. The diagnosis of psoriatic arthritis was made by rheumatologists and participants completed a self‐administered standardized questionnaire. The maximum BSA involved was determined from the case notes. Psoriatic arthritis was not significantly associated with sex, race, age of onset of psoriasis, a family history of psoriasis, smoking and alcohol consumption but was significantly associated with a family history of psoriatic arthritis (P < 0.001) and the maximum body surface involved (P = 0.05). Using multivariate analysis to control for variables, the presence of psoriatic arthritis was significantly associated with a family history of psoriatic arthritis (odds ratio [OR] = 20.5; 95% confidence interval [CI] = 2.49–169.10) and the maximum BSA involved (OR = 2.52; 95% CI = 1.33–4.75). Indian psoriatic patients were more likely to have psoriatic arthritis compared to the other races. A family history of psoriatic arthritis and a greater maximum body surface involved may be associated with having psoriatic arthritis in this study population of psoriasis patients.  相似文献   
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