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21.
目的 构建一套预防医学本科毕业生应对突发生物性公共卫生事件核心能力评价指标体系。方法 采用深入访谈和小组讨论等研究方法确定核心能力结构,并运用德尔菲法进行2轮专家咨询。以21位专家对该体系的咨询结果为依据,最终确定指标体系及其权重。采用Excel和SPSS 21.0软件进行数据整理和统计分析。结果 专家咨询的积极系数大于80%,权威系数大于0.7,均值为0.906。最终确定的指标体系由4个一级指标、10个二级指标、39个三级指标构成。结论 该评价指标体系可为探索提高毕业生核心能力的有效途径提供参考依据。 相似文献
22.
目的 探讨13-甲基十四烷酸(13-MTD)对局灶性脑缺血损伤的保护作用。 方法 线栓法制备大鼠右侧大脑中动脉缺血6,12及24 h模型。雄性SD大鼠随机分为假手术组、溶媒对照组及13-MTD 40(M40),80(M80),120 mg/kg(M120)干预组。采用Longa法进行神经功能缺失评分; 采用2,3,5-氯化三苯基四氮唑(TTC)染色法观察脑梗死体积; 采用Auto CAD图像分析软件计算脑水肿程度; 采用伊文思蓝(EB)检测血脑屏障(BBB)通透性。 结果 与溶媒对照组比较,13-MTD 40,80,120 mg/kg干预组均可明显改善不同脑缺血时限神经功能缺失症状,使脑梗死体积明显缩小,亦可使脑含水量和脑水肿程度减轻,EB渗出减少,且在缺血6 h时,M80组的效果最佳,并有量效差异。 结论 各剂量的13-MTD对不同时间大鼠局灶性脑缺血所致的脑损伤均有保护作用,在缺血6 h时,80 mg/kg的13-MTD疗效较为显著。 相似文献
23.
孤立性肺结节良恶性危险因素研究进展 总被引:2,自引:0,他引:2
孤立性肺结节的检出率随着CT影像技术的进步,有着显著的上升,并且当代人们对健康的意识也越来越强,而早期结节的性质由于多种因素的影响较难鉴别,因此,肺结节的良恶性如果能够在初期得到全面的评估,将具有积极的意义。本文对良恶性孤立性肺结节患者的年龄、性别、血清肿瘤标志物、CT影像学特点、吸烟史、既往肿瘤史等相关因素的价值做一综述。 相似文献
24.
Yiping Chen Zuan Lin Chenfang Miao Qianqian Cai Fenglan Li Zongfu Zheng Xinhua Lin Yanjie Zheng Shaohuang Weng 《RSC advances》2020,10(45):26765
The development of a simple detection strategy for trypsin (Try) is urgent, and is ascribed to the diagnostic value of Try in several diseases. Herein, a facile but effective fluorescence strategy for Try was developed based on the protamine (Pro)-induced aggregation of carbon quantum dots (CQDs). The fluorescence of negatively charged CQDs was quenched with Pro due to the assembly of CQDs and Pro (CQDs/Pro) through electrostatic interaction. However, the highly positively charged Pro, which is rich in basic arginine residues, was preferred to be hydrolyzed by Try. Try can induce the deaggregation of CQDs/Pro, thereby enabling the release of CQDs to restore the fluorescence intensity. Thus, the use of CQDs/Pro as a testing platform will be employed as a “turn-on” method for Try. In addition, the fluorescence-resuming response was proportional to Try, ranging from 25 ng mL−1 to 500 ng mL−1 with a limit of detection (LOD) of 8.08 ng mL−1. This “turn-on” fluorescence assay for Try was label-free, convenient, and relatively free of interference from coexisting substances. Actual applications for Try monitoring and trypsin inhibitor screening also illustrated the considerable prospect of CQDs in the clinical field, combined with the superiority of the simple mixing operation.In this work, a simple melting method was developed for carbon quantum dot fabrication to integrate with protamine as an effective signal-on fluorescence strategy for trypsin detection.With increasing attention being paid to human health for disease diagnosis and treatment, increasing efforts have been spent on the development of new analytical methods toward biological macromolecule detection.1,2 Trypsin (Try) is one of the most vital digestive proteases produced in pancreatic acinar cells, and can catalyze the hydrolysis of peptides mainly found at the C-terminus of lysine and arginine residues.3–5 Abnormal Try activity will be reflected in pancreatic function and the corresponding pathological changes of the human body. In general, Try is a biomarker for several diseases, such as acute pancreatitis, cystic fibrosis, and pancreatic cancer.5–7 Therefore, accurate monitoring for Try levels through simple and economical assays has attracted increasing interest in disease diagnosis and treatment.At present, considerable efforts have been devoted to developing efficient and reliable methods for Try detection based on various strategies, including colorimetry,8 electrochemistry,9 and fluorescence methods.10 Fluorescent approaches have been widely used due to their characteristics of simplicity, rapidity, sensitivity, and realizing real-time detection.11,12 Fluorescent methods for Try have mainly been developed based on the hydrolytic effect of Try using peptide chains or specific proteins as substrates,7,10,13,14 and using fluorescent dots, like CdTe QDs.14 Although current fluorescent methods are accurate and reliable, a simple and easy sensing system that detects Try with a controllable response integration modulated by Try through a biocompatible probe is still lacking. Given its special structural properties, protamine (Pro) is a highly cationic peptide under physiological conditions that possesses unique physiological function and substrates for enzymatic catalysis.8 The arginine-rich structure of protamine can also be catalyzed by Try as an ideal substrate for Try monitoring.8,15,16 Hence, the interaction system containing Pro and a fluorescence probe, such as AIEgen, can be applied for the analytical assembly of Try.17 With regard to the relatively complicated preparation of AIE, other fluorescent probes for Try detection are desirable and urgently needed.Among the current fluorescent nanomaterials, fluorescent carbon quantum dots (CQDs) have been used to construct biosensors due to their safety, unique optical properties, and ease of modification.18–20 Changing the structure or the surface properties of CQDs can result in a difference in the interaction and function between CQDs and external substances.21,22 Thus, various fluorescent sensors based on CQDs have been established to detect specific targets varying from ions, nucleic acids, and drugs.22–25 Positively and negatively charged carbon dots with controlled N-doping play opposite adsorption interaction with ssDNA in different applications.21–23 Hence, a series of different application systems can be proposed to establish by utilizing the different surface properties of CQDs.Herein, negatively charged CQDs, fabricated from a simple melting operation, were applied as the sensing probe for Try detection without any complex surface functionalization or conjugation and compared with other reported quantum dots,26 as shown in Scheme 1. Using Pro as the selective enzymatic substrate for Try, the integration of the prepared CQDs and Pro induce them to assemble and form an aggregation-caused quenching system of CQDs and Pro (CQDs/Pro) via electrostatic interaction. Under the strong and specific hydrolysis of Try to Pro, Pro loses its function with CQDs, and then the CQDs/Pro disaggregates to recover the fluorescence intensity. This facile system using Pro as the medium for inducing CQD aggregation provided novel insights into the design of some quantum dots with the appropriate surface property for the fabrication of simple, selective, and effective fluorescence assays for bioanalysis without a complicated surface functionalization.Open in a separate windowScheme 1The fabrication of CQDs and its electrostatic interaction with protamine as a simple quenching platform for trypsin detection. 相似文献
25.
目的比较大鼠大脑中动脉闭塞(MCAO)模型和光化学诱导局灶性脑缺血模型的磁共振影像及超微结构的差异。方法分别建立大鼠MCAO和光化学诱导局灶性脑缺血模型,利用小动物磁共振成像系统观察脑缺血区域及周边血管分布,结合透射电镜技术比较两种模型缺血区超微结构的变化。结果MCAO模型缺血区范围较大且不稳定,细胞结构破坏严重,血管变形显著,新生血管较少。光化学诱导模型缺血区范围较小且稳定,细胞结构损伤区域较小,新生血管较多。结论两种模型方法各有优缺点,均为脑缺血后血管损伤保护及溶栓治疗的研究提供实用性工具,可根据科研需求选取适合的造模方法 相似文献
26.
目的研究金铁锁Psammosilene tunicoides根的化学成分。方法经硅胶、Sephadex LH-20凝胶、ODS反相硅胶等柱色谱方法进行分离,并运用NMR、HR-ESI-MS等波谱学方法进行化合物的结构鉴定。结果从金铁锁根80%乙醇水提取物中分离得到2个麦芽酚苷类化合物,分别鉴定为麦芽酚-3-O-[6-O-(4-O-α-L-吡喃鼠李糖基)-Z-p-香豆酰基]-β-D-吡喃葡萄糖苷(1)和麦芽酚-3-O-[6-O-(4-O-α-L-吡喃鼠李糖基)-E-p-香豆酰基]-β-D-吡喃葡萄糖苷(2)。结论化合物1和2为新的麦芽酚苷类化合物,分别命名为金铁锁酚苷A和B。 相似文献
27.
28.
29.
《Journal of stroke and cerebrovascular diseases》2022,31(4):106370
Background and AimsAntiretroviral treatment (ART) era HIV-associated stroke data from Sub-Saharan Africa is limited. We determined the prevalence of HIV in patients presenting with acute symptomatic stroke; and compared risk factors, clinical characteristics, and brain imaging with age-matched stroke patients without HIV.MethodsWe conducted a retrospective study of adults presenting with any type of stroke to a South African tertiary hospital in a 12-month period. Patients living with HIV (PLWH) and HIV-uninfected patients (HIV-) were matched on age group (1:2 ratio).ResultsTheacute stroke prevalence of HIV infection was 9.3% (95%CI: 7.4-11.2%) among 884 stroke patients. Mean age at presentation in PLWH was 46 (±11) years compared to 55 (±14) years in HIV- (p<0.001). Hypertension (p=0.011) and dyslipidaemia (p=0.005) were less prevalent in PLWH. Concurrent infection was more prevalent in PLWH (p=<0.001), largely in patients with low CD4 counts. PLWH with higher CD4 counts had traditional risk factors and less concurrent infection. Among PLWH, 39.3% had been started / restarted on ART within 6-months. Basal ganglia infarcts (p=0.014) and multiple vascular territory involvement (p=0.002) was more common in PLWH. Clinical presentation, ischaemic stroke type, and in-hospital outcomes did not differ between groups.ConclusionStroke patients with HIV were younger, had less traditional cardiovascular risk factors, and more concurrent infections than patients without HIV when CD4 count was low. Recent ART initiation or reinitiation rates were high. Significant differences in CT brain imaging findings were seen. Understanding the multifactorial mechanisms underlying increased stroke risk in this population is crucial. 相似文献
30.