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针对日常使用中遇到的Brilliance 16排螺旋CT高压系统、机架以及控制器局域网络(CAN)通讯等故障现象进行分析与维修,最终通过更换滤波电容、机架数据采集控制器(DMC)电源以及信号刷等配件得以排除故障。通过对故障准确判断以及合理运用厂家Service模式下的维修工具软件快速解决故障,保障了影像科检查工作的顺利进行,从而提高设备的稳定性。  相似文献   
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目的探讨乙肝相关性肝癌临床病理学特征与溶血磷脂酸(LPA)和高敏C反应蛋白(hs-CRP)表达的相关性。方法选取2019年1月至2020年1月间河南省驻马店市中心医院收治的198例乙肝相关性肝癌患者作为乙肝组,198例酒精相关性肝癌患者作为酒精组。两组患者都进行血清hs-CRP和LPA表达检测,调查患者的病理学特征并进行相关性分析。结果乙肝组患者血清hs-CRP和LPA含量均高于酒精组,差异均有统计学意义(均P <0.05)。两组患者血清ALP、AFP、ALT、AST和GGT含量比较,差异均无统计学意义(P> 0.05)。乙肝组不同临床分期和组织学分化患者的血清hs-CRP和LPA含量比较,差异均有统计学意义(均P <0.05)。乙肝组患者的临床分期和组织学分化与血清hs-CRP和LPA表达均存在相关性,差异均有统计学意义(均P <0.05)。患者的临床分期和组织学分化均为影响hs-CRP和LPA表达的重要因素,差异均有统计学意义(均P <0.05)。结论相对于酒精相关性肝癌,乙肝相关性肝癌的血清hs-CRP和LPA呈现高表达,与患者的临床病理学特征存在相关性。  相似文献   
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In the field of drug development, technology for producing human metabolites at a low cost is required. In this study, we explored the possibility of using prokaryotic water-soluble cytochrome P450 (CYP) to produce human metabolites. Streptomyces griseolus CYP105A1 metabolizes various non-steroidal anti-inflammatory drugs (NSAIDs), including diclofenac, mefenamic acid, flufenamic acid, tolfenamic acid, meclofenamic acid, and ibuprofen. CYP105A1 showed 4′-hydroxylation activity towards diclofenac, mefenamic acid, flufenamic acid, tolfenamic acid, and meclofenamic acid. It should be noted that this reaction specificity was similar to that of human CYP2C9. In the case of mefenamic acid, another metabolite, 3′-hydroxymethyl mefenamic acid, was detected as a major metabolite. Substitution of Arg at position 73 with Ala in CYP105A1 dramatically reduced the hydroxylation activity toward diclofenac, flufenamic acid, and ibuprofen, indicating that Arg73 is essential for the hydroxylation of these substrates. In contrast, substitution of Arg84 with Ala remarkably increased the hydroxylation activity towards diclofenac, mefenamic acid, and flufenamic acid. Recombinant Rhodococcus erythrocyte cells expressing the CYP105A1 variant R84A/M239A showed complete conversion of diclofenac into 4′-hydroxydiclofenac. These results suggest the usefulness of recombinant R. erythropolis cells expressing actinomycete CYP, such as CYP105A1, for the production of human drug metabolites.  相似文献   
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PurposeOptical coherence tomography angiography (OCTA) was utilized to examine changes in ocular surface squamous neoplasia (OSSN) vascular patterns over time in individuals treated with topical medical therapy.MethodsTen individuals with OSSN diagnosed by clinical examination and high resolution (HR)-optical coherence tomography (OCT) were recruited. All individuals received topical immuno- or chemotherapy. OCTA images were obtained and analyzed at three points: presentation, mid-treatment and tumor resolution. Tumor metrics including tumor area (TA), tumor volume (TV), tumor depth (TD), and total tumor density (TTD) were calculated. Vessel area density (VAD) was also quantified within the OSSN, the subepithelium under and adjacent to the OSSN and the subepithelium of the uninvolved, contralateral eye. Vascular network changes were also subjectively evaluated.ResultsTA, TV, TD and TTD all significantly decreased with time (p < 0.001). The mean VAD within the OSSN significantly decreased (p < 0.001) between visits (presentation: 26.52 ± 6.8%, mid-treatment: 7.19 ± 5.88%, tumor resolution: 0.11 ± 0.34%). The mean subepithelial VAD under the OSSN also decreased with time (23.22 ± 11.03%, 20.99 ± 5.99% and 19.58 ± 7.08%), and after resolution the sub-tumor VAD (19.58 ± 7.08%) was comparable to the subepithelial VAD in the contralateral eye (15.47 ± 4.37%, p > 0.05). The mean VAD in the subepithelium adjacent to the OSSN increased with treatment, then decreased significantly between mid-treatment and resolution (23.26 ± 4.54, 28.30 ± 7.43% and 21.68 ± 6.10%, p = 0.009). Qualitatively, the tumor subepithelial vascular network was complex and dense but with tumor resolution appeared less tortuous and similar to the uninvolved eye.ConclusionOCTA provided insight into the pathophysiology of tumor angiogenesis, showing decreased vascular density and normalization of vascular networks associated with tumor resolution.  相似文献   
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AIM: To explore the changes in lens thickness and density with age. METHODS: A Chinese population-based retrospective study was performed. A total of 497 individuals (490 right eyes and 495 left eyes), ranging from 3 to 69 years old were included. Lens images obtained from IOL Master 700 were used to measure lens thickness and density. Piecewise regression model was chosen to illustrate the relationship of lens thickness and density with age. RESULTS: The proportion of people aged 3-18, 19-40, over 40 was 38.6%, 50.9% and 10.5% respectively. The whole lens thickness decreased with age during the first 7 years of life, kept stable from 8 to 16 years old, and then increased at the rate of about 27 µm per year. The thickness of the lens cortex and nucleus tended to decrease first and then increase with age, which was dependent on age stages. The whole lens density also decreased with age until 7 years old. The increasing rate of lens density was different in different age groups. The whole lens density increased rapidly from 7 to 22 years old and slowed down after 22 years old. Similarly, the changing tendency of lens cortical and nuclear density differed in different age phases. CONCLUSION: Both lens thickness and density are significantly associated with age, whereas they do not change linearly with age. Moreover, it is necessary to increase the population over 40 years old and conduct further research.  相似文献   
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PurposeTo test the following hypotheses: (a) balloon or stent assistance increases coil packing density (CPD) in the endovascular treatment of intracranial aneurysms, and (b) CPD correlates to ostium area (OA) and aneurysm volume (AV).Materials and MethodsThis retrospective study included 60 aneurysms (54 ruptured and 6 unruptured) treated with simple coiling (SC) (n = 18), balloon-assisted coiling (BAC) (n = 7), or stent-assisted coiling (SAC) (n = 35) at the authors’ institution between August 2017 and December 2019. AV and OA measurements were obtained from 3-dimensional digital subtraction angiography images using commercial software. Coil sizes were retrieved from patient files, and coil volume (CV) measurements were obtained from https://www.angiocalc.com/. Analysis of covariance, multivariate covariance analysis, and Pearson correlation analyses were performed.ResultsThe median value for AV, CV, CPD, and OA was 63.4 mm3 (range, 5.5–1,771.4 mm3), 23.13 mm3 (range, 2.03–296.95 mm3), 33.29% (range, 13.41%–81.02%), and 10.7 mm2 (range, 2.7–49.9 mm2), respectively. Multivariate analysis showed that the CPD values were not significantly different among the treatment groups, although OA significantly differed between the SC and SAC groups (P < .05). Pearson correlations showed that similar to AV, OA was negatively correlated with CPD (r = ?0.321, P < .05).ConclusionsThe CPD value in cerebral aneurysms treated with BAC or SAC did not differ from that in aneurysms treated with SC.  相似文献   
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