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991.
EcoRI is an important biomacromolecule in live cells and protects bacterial cells against foreign DNA. In this work, we developed a simple and convenient G-triplex (G3) (5′-TGGGAAGGGAGGGAATTCCCT-3′)-based colorimetric assay for the rapid and selective detection of EcoRI activity and inhibition. The sequence specifically responds to EcoRI in the presence of K+ and hemin to form a G-triplex/hemin complex. Taking advantage of G-triplex, EcoRI activity was investigated under the optimized conditions. The absorption intensity ratio displayed a linear relationship against the concentration of EcoRI in the range 0 to 100 U mL−1, and the detection limit was 5.7 U mL−1. Furthermore, G3 showed good selectivity, and the ability to be used to screen for EcoRI inhibitors, indicating its potential in detection and analysis applications.

A new G-triplex-based probe was developed for detecting EcoRI activity and inhibition. The probe showed good selectivity towards EcoRI. The assay was colorimetric and can be monitored by the naked eye.  相似文献   
992.
Graphene sheets decorated with nickel or copper oxides that were anchored on polyaniline (denoted as PANI-graphene/NiO and PANI-graphene/CuO) were prepared by a simple, easy to-control electrochemical method and applied as novel materials for sensitive and selective methanol sensing. The fabricated sensors exhibited good electrocatalytic activity, appropriate dynamic linear range (20–1300 mM), sensitivity (0.2–1.5 μA mM−1 cm−2) and excellent selectivity towards methanol. It should be highlighted from the selectivity tests that no significant interference was observed from ethanol and other alcohols. To our best knowledge, using inexpensive but efficient transition metals like Ni, Cu instead of Pt, Pd and their composites with PANI, graphene would be scientifically novel and practically feasible approach for sensor fabrication that could be potentially used to identify methanol adulteration in counterfeit alcoholic beverages.

PANI/graphene/NiO or PANI/graphene/CuO were prepared by a simple, easy to-control electrochemical method and applied as novel materials for sensitive and selective methanol sensing.  相似文献   
993.
青年人胃癌30例临床分析   总被引:4,自引:1,他引:3  
目的探讨青年人胃癌的临床特点和提高对本病早期诊断。方法对本组30例青年人胃癌的临床资料、内镜特征进行分析、比较。结果青年人胃癌的部位多位于胃窦及胃体部,病变类型以BorramnnIII和BorramnnIV期为多,年龄越小,分期越晚。结论青年人胃癌早期症状无特异性,容易漏诊、误诊,临床大夫须提高对本病认识。  相似文献   
994.
Atraumatic convexity subarachnoid hemorrhage (c-SAH) concomitant with large artery atherosclerosis (LAA) stroke has been rarely discussed in the literature. Our aim in this study is to characterize the clinical and neuroradiological features of patients with LAA stroke and c-SAH.A retrospective study from a single institution was performed between January 2016 and June 2020. Only patients diagnosed with c-SAH and LAA stoke were included in this study. The clinical presentation and neuroimaging finding were summarized by our experienced neurologists.In total, 12 patients (8 men, 4 women), ranging in age from 45 to 75 years, were identified. All of them had cardiovascular risk factors and hypertension was the commonest (50%). Almost all patients presented hemiparesis (91.7%). Other clinical presentations included, dysarthria (41.7%), hemianesthesia (33.3%), facial palsy (33.3%), aphasia (16.7%), and cognitive impairment (8.3%). Internal border-zone (IBZ) infarction and cortical border-zone (CBZ) infarction occurred in 12 and 3 patients, respectively. c-SAH might occurred in different cortical sulcis. Percentages of frontal lobe, parietal lobe and fronto-parietal lobe were 41.7% (n = 5), 25% (n = 3) and 25% (n = 3), respectively. All ischemic lesions were ipsilateral to the sites of c-SAH. High-grade atherosclerotic stenosis of large artery was detected in all patients. The M1 segment of middle cerebral artery (MCA) is the second most common atherosclerotic artery after internal carotid artery (ICA).Our data suggest that LAA stroke is always ipsilateral to the site of c-SAH. Severe atherosclerotic changes can also been seen in the M1 segment of MCA apart from extracranial ICA. Moreover, border zone infarction may be a specific form of infarct when c-SAH is confronted with LAA stroke.  相似文献   
995.
Background:For patients with acute exacerbation of chronic obstructive pulmonary disease (AECOPD) complicated by respiratory acidosis, noninvasive ventilation therapy is thought to be the first-line treatment. In patients with AECOPD, the effect of high-flow nasal oxygen therapy is not well studied. In this study, the existing data will be synthesized to obtain an effective rate of movement of nasal oxygen therapy in patients with AECOPD.Methods:Using PubMed, EMBASE, Cochrane Library, Web of Science, Scopus, a systematic search will be undertaken to identify randomized controlled trails (RCTs) on the clinical therapeutic effects of rate of movement of nasal oxygen therapy in patients with AECOPD without language constraints from their onset to November 2020. To classify potentially qualifying tests, we will also review Google Scholar, ClinicalTrials.gov, and the reference lists of included studies. Two independent reviewers will review inclusion trials and execute data extraction. Research bias and quality will be measured using the Cochrane Collaboration Bias Method 2.0. The findings of the analysis will be pooled using a formula of fixed-effects or random-effects. We will address any dispute by dialogue, and cases of disagreement will be mediated by a third author.Results:The current research will examine the clinical therapeutic results of patients with AECOPD with rate of movement of nasal oxygen therapy.Conclusion:To assess the efficacy of rate of movement of nasal oxygen therapy in patients with AECOPD, the present analysis would provide consistent facts.OSF registration number:November 18, 2020.osf.io/umd48. (https://osf.io/umd48/).  相似文献   
996.
To introduce a novel technique of using individualized 3D printing occipitocervical fusion instrument (3D-OCF) for the treatment of upper cervical deformity with atlantoaxial joint dislocation.The surgery for deformity of the craniocervical junction area is a challenge in the field of spine. If the surgical deviation is too large to injure the spinal cord or vertebral artery, it will cause catastrophic damage to the patient. Therefore, it is controversial whether these patients should undergo surgical treatment. We provide a novel surgical approach for the challenging upper cervical surgery through 3D-OCF and a typical patient.We present a 54-year-old female patient, who suffered from dizziness and numbness in her limbs for 8 months. After the patient was admitted, we performed the three-dimensional CT scan, modeled using Mimics software 17.0, and designed customized occipitocervical fusion instrument. Besides, we repeatedly perform simulated surgery based on 3D-printed models before surgery.The operative time was 142 minutes and the intraoperative blood loss was 700 mL. X-ray showed reduction of atlantoaxial dislocation and accurate position of internal fixation. The patient''s symptoms were significantly relieved: the sensation of dizziness and numbness of limbs was obviously relieved, and the sense of banding in chest, abdomen, and ankle was disappeared. At the last follow-up, imaging showed that 3D-OCF had bone-integration and Syringomyelia was disappeared. The patient''s cervical JOA (Japanese Orthopaedic Association) score increased from 10 points to 17 points.Individualized 3D-OCF can improve the safety and accuracy of upper cervical surgery, reduce the operative time and the number of fluoroscopy. Our study provides a novel surgical approach for the challenging upper cervical surgery.  相似文献   
997.
Based on the Thompson classification of intervertebral discs (IVDs), we systematically analyzed gene expression differences between severely degenerated and mildly degenerated IVDs and explored the underlying molecular mechanisms using bioinformatics methods and multichip integration. We used multiomics analysis, includes mRNA microarray and methylation chips, to explore the genetic network and mechanisms of lumbar disc herniation (LDH). Subsequently, the Combat function of the R language SVA package was applied to eliminate heterogeneity between the gene expression data. And the protein–protein interaction (PPI) network, gene ontology (GO), and molecular pathways were used to constructs the mechanisms network. Consequently, we obtained 149 differentially expressed genes. Related molecular pathways are the following: ribosome activity, oxidative phosphorylation, extracellular matrix response. Besides, through PPI network analysis, genes with higher connectivity such as UBA52, RPLP0, RPL3, RPLP2, and RPL27 were also identified, suggesting that they play important regulatory roles in the complex network associated with LDH. Additionally, cg12556991 (RPL27) and cg06852319 (RPLP0) were found to be LDH-related candidate DNA methylation modification sites in the IVDs tissue of LDH patients. In conclusions, ribosome activity, oxidative phosphorylation, and extracellular matrix response may be potential molecular mechanisms underlying LDH, while hub genes involved in UBA52, RPLP0, RPL3, RPLP2, and RPL27, and candidate DNA methylation modification sites of cg12556991and cg06852319 are likely key regulators in the development of LDH.  相似文献   
998.
目的探讨儿童左束支区域起搏(LBBAP)的安全性及有效性.方法回顾性分析2019年1月至6月于北京安贞医院小儿心脏科住院采用LBBAP方式行永久心脏起搏器植入术的6例患儿(男1例、女5例)的临床资料、起搏心电图及参数并进行随访.组间比较采用t检验.结果6例患儿年龄9~14岁,体重26~48 kg;三度房室传导阻滞5例,右室心尖起搏术后伴心功能下降1例;1例患儿心功能降低,余5例心功能均正常;QRS波时限(95±13)ms;左心室舒张末径(LVEDD)Z值为1.85±0.65.起搏心电图V1呈右束支传导阻滞样,QRS波时限(111±20)ms,与术前相比,差异无统计学意义(t=-1.610,P>0.05).起搏阈值为(0.85±0.26)V,感知(15.0±4.3)mV,阻抗(717±72)Ω.3例可记录到P电位.起搏钉至左心室激动时间为(56±5)ms,不同输出电压下数值恒定.术后超声提示电极均位于室间隔左心室心内膜下.随访无心肌穿孔、电极脱位等并发症发生,患儿术后3个月阈值、感知及阻抗分别为(0.60±0.09)V、(16.1±3.9)mV、(662±78)Ω.左心室射血分数(LVEF)降低者LBBAP术后3d恢复正常(45%比57%).术后3个月LVEDD Z值降至(1.1±0.3),较术前明显减小(t=2.383,P<0.05).结论LBBAP可实现窄QRS波起搏,接近生理性起搏,起搏参数稳定,可快速、有效地纠正长期心动过缓所致的左心扩大及长期右室心尖起搏所致的心功能低下及心脏扩大.较大年龄儿童行LBBAP近期安全性、有效性好,远期潜在风险有待进一步观察研究.  相似文献   
999.
目的探讨SGCE基因变异导致儿童期起病的肌阵挛肌张力障碍综合征患儿的临床特点及基因分型.方法收集2018年5月至2019年10月首都医科大学附属北京儿童医院神经内科和北京大学第一医院儿科共同收集的9例经全外显子组测序方法以及多重链接依赖的探针扩增技术确诊的SGCE基因变异导致的肌阵挛肌张力障碍综合征患儿的临床资料,并对患儿进行随访,对临床特点及基因变异结果进行回顾性总结分析.结果9例患儿中男4例、女5例,起病年龄1岁~3岁2月龄.首发症状为肌阵挛者4例,肌张力障碍者5例.病程中,9例均有肌阵挛症状,8例有肌张力障碍症状.8例肌阵挛表现为双上肢不自主抖动.6例病程中曾有下肢突然抖动一下,导致步态不稳甚至跌倒.肌张力障碍症状表现为行走姿势异常,其中5例右下肢受累,3例左下肢受累.3例有阳性家族史.9例患儿智力发育均正常.发作期及发作间期视频脑电图未见明显异常,肌电图及头颅磁共振成像正常.基因结果示9例携带SGCE基因变异,其中3例为移码变异,2例为无义变异,2例为错义变异,1例为大片段缺失变异,1例为剪切位点变异;7例为遗传性变异,均为父源,2例为新生变异.治疗上,8例加用美多芭口服,6例肌阵挛较前有所减少,走路姿势不同程度改善.4例加用硝西泮,2例有效.结论SGCE基因变异可导致肌阵挛肌张力障碍综合征,多在幼儿期或学龄前期起病,肌阵挛和肌张力障碍均可为首发症状.非癫痫性肌阵挛是其突出症状,且有上肢优势特点.绝大多数病程中伴肌张力障碍,部分肌张力障碍可自行缓解.SGCE基因为母源印记基因,遗传性变异多为父源.  相似文献   
1000.
【摘要】 目的 分析早期蕈样肉芽肿(MF)皮损的反射性共聚焦显微镜(RCM)与组织病理学特征的一致性,探讨RCM作为病理学诊断早期MF的辅助价值及动态监测治疗反应的可行性。方法 2014年1月至2018年1月在杭州市第三人民医院皮肤科门诊收集临床疑诊MF病例40例,男26例,女14例,年龄(47.0 ± 17.6)岁。根据总结的早期MF的RCM特征,对活检部位进行初步定位后行组织病理学检查,对比MF的RCM与病理特征。对MF确诊病例进行窄谱中波紫外线联合干扰素治疗,运用RCM对靶向皮损跟踪随访,9个月后评价疗效。结果 在40例临床疑诊MF病例中,根据RCM特征初步诊断典型MF 8例,疑似MF18例,排除14例;根据MF病理学特征诊断典型MF12例,疑似14例,排除14例。一致性分析显示,RCM特征分类与病理诊断结果的Kappa系数为0.848,P < 0.01。RCM与组织病理学特征之间表皮低折光细胞浸润的相关性最高(Kappa系数 = 1,P = 0.005),其次是红斑期的真皮纤维化(Kappa系数 = 0.714,P = 0.035)。MF的RCM特征随着治疗的进行逐步恢复正常,但直至临床皮损完全缓解,非典型淋巴细胞依然存在。结论 RCM技术可用于早期疑诊MF皮损的病理取材定位,同时可尝试作为一种动态监测MF疗效的方法。  相似文献   
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