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四位一体联动打造分析化学教学新模式
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作者 宋文璟 范荣华 于龙 《大学化学》 CAS 2023年第5期6-12,共7页
面向国家亟需公共卫生人才这一新形势,针对分析化学教学过程中存在的问题,基于产出导向教育(OBE)理念,将面授、雨课堂、思维导图、Excel有机融合,系统联动,构建“四位一体”的混合教学模式。通过课前预习准备、课中互动传授、课后归纳重... 面向国家亟需公共卫生人才这一新形势,针对分析化学教学过程中存在的问题,基于产出导向教育(OBE)理念,将面授、雨课堂、思维导图、Excel有机融合,系统联动,构建“四位一体”的混合教学模式。通过课前预习准备、课中互动传授、课后归纳重构,引导学生利用碎片化时间自主学习,将知识传授、价值引领和能力培养深度结合,实现立德树人的根本任务,取得了良好效果。 展开更多
关键词 分析化学 公共卫生 产出导向教育 雨课堂 思维导图
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亚实性肺结节CT征象在良恶性鉴别及腺癌恶性侵袭程度评估中的价值 被引量:28
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作者 郭芳芳 李欣菱 +6 位作者 王欣悦 郑文松 王卿 宋文静 于铁链 范亚光 王颖 《中国肺癌杂志》 CAS CSCD 北大核心 2018年第6期451-457,共7页
背景与目的亚实性肺结节为肺原发腺癌的常见计算机体层成像(computed tomography,CT)表现,依据其CT影像特征预测病理分型对确定临床治疗策略具有临床价值。本研究根据病理分类,回顾性分析良性、不典型腺瘤样增生(atypical adenomatous h... 背景与目的亚实性肺结节为肺原发腺癌的常见计算机体层成像(computed tomography,CT)表现,依据其CT影像特征预测病理分型对确定临床治疗策略具有临床价值。本研究根据病理分类,回顾性分析良性、不典型腺瘤样增生(atypical adenomatous hyperplasia,AAH)/原位腺癌(adenocarcinoma in situ,AIS)/微侵袭性腺癌(minimally invasive adenocarcinoma,MIA)、侵袭性腺癌三组亚实性肺结节的CT征象,评估其在良恶性鉴别及恶性侵袭程度判别中的价值。方法回顾性分析106例经手术切除亚实性结节的CT征象。依据手术病理分为良性和恶性组,恶性组根据侵袭程度分为无/微侵袭组(AAH/AIS/MIA)、侵袭性腺癌组,测量结节大小、实性成分比例、瘤肺界面、形状、边缘、胸膜牵拉征、空气支气管征、结节内血管异常等CT征象。根据单因素分析(χ2检验、非参数检验Mann-Whitney U检验)结果筛选有统计学差异的变量,纳入Logistic回归多因素分析。结果 Logistic回归分析显示清晰的瘤肺界面、空气支气管征以及结节内血管异常是恶性结节的重要预测指标,风险比分别为38.1(95%CI:5.0-287.7;P<0.01)、7.9(95%CI:1.3-49.3;P=0.03)、7.2(95%CI:1.4-37.0;P=0.02)。更大的实性成分所占比例是侵袭性腺癌与AAH/AIS/MIA组鉴别的重要指标,其风险比分别为1.04(95%CI:1.01-1.06,P=0.01)。结论亚实性结节中出现清晰的瘤肺界面、空气支气管征、结节内血管异常提示其恶性概率增加。恶性结节中实性成分所占比例越大预示着侵袭性更高。 展开更多
关键词 肺肿瘤 亚实性结节 计算机体层成像 定量变量 定性变量 良性 恶性
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基于芳香胺化合物的光催化脱卤加氢 被引量:1
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作者 孟涤 朱倩 +5 位作者 魏燕 甄胜利 段苒 陈春城 宋文静 赵进才 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2020年第10期1474-1479,共6页
近年来,光催化活化碳卤键已经成为构筑新化学键的有力方法.其基本原理在于利用光激发产生的高活性激发态或中间物种,经由电子转移过程实现碳卤键的断裂产生碳自由基和卤离子(C–X+e-→C·+X–).碳自由基通过加氢或者或亲电进攻等途... 近年来,光催化活化碳卤键已经成为构筑新化学键的有力方法.其基本原理在于利用光激发产生的高活性激发态或中间物种,经由电子转移过程实现碳卤键的断裂产生碳自由基和卤离子(C–X+e-→C·+X–).碳自由基通过加氢或者或亲电进攻等途径完成反应,实现碳卤键到碳氢、碳碳等化学键的转化.目前已报道的用于活化碳卤键的光催化剂包括过渡金属(如钌、铱)配合物,过渡金属盐(CeⅢCl63–)、有机小分子光(二氢苯二嗪、苯基吩噻嗪、苝酰亚胺以及芘类衍生物分子)等.本工作中我们开发了基于小分子芳香胺,包括N,N,N’,N’-四甲基对苯二胺(TMPD)与N,N,N’,N’-四甲基联苯胺(TMB)等作为光催化剂实现高惰性芳香卤代化合物脱卤加氢的催化体系.荧光强度/寿命测试表明芳香胺的强还原性单重激发态可通过扩散控制的电子转移实现惰性卤代底物(氯苯,六氟苯等)中碳卤键的解离;并且原位顺磁共振直接观察到了这一步骤产生的芳基自由基以及TMPD正离子自由基;自由基捕获实验也为解离电子转移活化碳卤键提供了进一步的支持.芳香胺分子在计量反应条件下可同时作为光敏剂和电子/氢给体可在紫外光照下(λ>360 nm)实现芳香卤代化合物的脱卤加氢,并表现出较高的转化率和选择性:溴苯乙酮(86%, 90%)、六氟苯(91%,五氟苯26%/1,2,4,5-四氟苯17%)、氯苯(63%,80%).引入N,N-二异丙基乙二胺(DIPEA)作为电子给体,能够还原芳香胺正离子自由基完成催化剂循环, DIPEA同时作为氢给体参与芳基自由基加氢.我们在催化反应条件下(5mol%芳香胺)调研了脱卤加氢的卤代底物范畴.以TMPD为例,对溴苯乙酮光照4小时后可得到90%脱溴产物;相对难还原的溴苯经过6小时光反应脱卤达到37%.六氟苯经过24小时反应后可以脱去1-2个氟,生成五氟苯(25%)和1,2,4,5-四氟苯(50%).对氯苯甲酸甲酯在7.5小时反应后得到了72%的加氢产物;而对于更难还原的氯苯两小时光照可生成约40%的脱氯产物(增加TMPD用量可进一步提高脱氯效率至63%).TMPD催化杂环卤代化合物脱卤的效果也较好,如3-溴噻吩(18 h, 41%)和3-溴-4甲基吡啶(25 h, 60%).另外TMB和4,4’,4’’-(1,3,5-三嗪-2,4,6-三基)三苯胺作为光催化剂也可实现脱卤加氢.我们进一步研究了典型持久性有机污染物2,2’,4,4’-四溴联苯醚(BDE47)的光催化脱溴反应, 30小时光照后脱溴效率可达83%,并且产生了40%的全脱溴产物联苯醚.脱溴中间产物分布表明邻位溴脱除速率高于对位溴.这一结果与解离电子转移活化碳卤键的机理一致.总而言之,我们的工作表明小分子芳香胺光敏剂的激发态能够通过扩散控制的电子转移活化碳卤键.它们作为光催化剂可实现多种有机卤化物的脱卤加氢. 展开更多
关键词 碳卤键活化 光催化 脱卤加氢 卤代有机污染物 环境修复
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融合现代信息技术的化学实验成绩评定体系 被引量:1
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作者 宋文璟 刘畅 《大学化学》 CAS 2021年第2期28-33,共6页
科学的成绩评定方法能够充分调动学生实验学习的积极性,从而提高实验教学质量。从新时代化学实验教学的需求出发,分析构建与现代信息技术深度融合的成绩评定体系的必要性,并制定了涵盖预习、操作、数据质量、计算、报告和文献于一体的... 科学的成绩评定方法能够充分调动学生实验学习的积极性,从而提高实验教学质量。从新时代化学实验教学的需求出发,分析构建与现代信息技术深度融合的成绩评定体系的必要性,并制定了涵盖预习、操作、数据质量、计算、报告和文献于一体的模块化、等级制评定体系及详细指标。同时利用Excel和MATLAB软件实现了数据的自动评判与总分统计。 展开更多
关键词 化学实验 成绩 自动评定 等级制 模块化
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A Rapidly Convergence Algorithm for Linear Search and its Application
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作者 Jianliang Li Hua Zhu +1 位作者 Xianzhong Zhou wenjing song 《Numerical Mathematics A Journal of Chinese Universities(English Series)》 SCIE 2006年第4期299-305,共7页
The essence of the linear search is one-dimension nonlinear minimization problem, which is an important part of the multi-nonlinear optimization, it will be spend the most of operation count for solving optimization p... The essence of the linear search is one-dimension nonlinear minimization problem, which is an important part of the multi-nonlinear optimization, it will be spend the most of operation count for solving optimization problem. To improve the efficiency, we set about from quadratic interpolation, combine the advantage of the quadratic convergence rate of Newton's method and adopt the idea of Anderson-Bjorck extrapolation, then we present a rapidly convergence algorithm and give its corresponding convergence conclusions. Finally we did the numerical experiments with the some well-known test functions for optimization and the application test of the ANN learning examples. The experiment results showed the validity of the algorithm. 展开更多
关键词 线性搜索 非线性优化 加速收敛 学习算法
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Canonical Correlation between the Leaf Quality Indicators of "Moderate Aroma" Flue-cured Tobacco
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作者 Lin MENG Yuangang DAI +4 位作者 Chengdong WANG Shusheng WANG wenjing song Yuanhua WU Yimin XU 《Asian Agricultural Research》 2015年第9期41-45 49,49,共6页
In order to find out the correlation between tobacco quality evaluation indicators in China's traditional " moderate aroma" tobaccoproducing areas and simplify the tobacco quality evaluation indicators,w... In order to find out the correlation between tobacco quality evaluation indicators in China's traditional " moderate aroma" tobaccoproducing areas and simplify the tobacco quality evaluation indicators,we evaluate the appearance quality and smoking quality of 143 flue-cured tobacco leaf samples in China's " moderate aroma" tobacco-producing areas,test the physical traits and chemical component,and analyze the canonical correlation between four quality evaluation indicators. The results show that there is significant or extremely significant canonical correlation between four evaluation indicators( tobacco smoking quality,chemical component,appearance quality and physical trait quality); the cumulative variance contribution rate of evaluation indicators is in the order of chemical component( 69. 17%) > appearance quality( 68. 76%) > physical traits( 64. 13%); appearance quality is most closely related to physical traits( 93. 84%). The individual indicators for tobacco quality evaluation make different contribution to the correlation between quality evaluation indicators. The chemical component evaluation indicators mainly include total sugar and ratio of total sugar to betaine; sensory taste indicators mainly include aroma volume,smoke concentration,irritation and softness degree; physical trait evaluation indicators mainly include leaf weight,leaf length and leaf density; appearance quality indicators mainly include leaf organizational structure,color,maturity and identity. Studies have shown that in the large-scale ecoregion,using canonical correlation analysis to simplify tobacco quality evaluation indicators is feasible. 展开更多
关键词 Flue-cured TOBACCO QUALITY Evaluation INDICATORS C
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MiRNA 24-3p-rich exosomes functionalized DEGMA-modified hyaluronic acid hydrogels for corneal epithelial healing
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作者 Xiaomin Sun wenjing song +11 位作者 Lijing Teng Yongrui Huang Jia Liu Yuehai Peng Xiaoting Lu Jin Yuan Xuan Zhao Qi Zhao Yingni Xu Jingjie Shen Xiaoyun Peng Li Ren 《Bioactive Materials》 SCIE CSCD 2023年第7期640-656,共17页
The damage of corneal epithelium may lead to the formation of irreversible corneal opacities and even blindness.The migration rate of corneal epithelial cells directly affects corneal repair.Here,we explored ocu-micro... The damage of corneal epithelium may lead to the formation of irreversible corneal opacities and even blindness.The migration rate of corneal epithelial cells directly affects corneal repair.Here,we explored ocu-microRNA 24-3p(miRNA 24-3p)that can promote rabbit corneal epithelial cells migration and cornea repair.Exosomes,an excellent transport carrier,were exacted from adipose derived mesenchymal stem cells for loading with miRNA 24-3p to prepare miRNA 24-3p-rich exosomes(Exos-miRNA 24-3p).It can accelerate corneal epithelial migration in vitro and in vivo.For application in cornea alkali burns,we further modified hyaluronic acid with di(ethylene glycol)monomethyl ether methacrylate(DEGMA)to obtain a thermosensitive hydrogel,also reported a thermosensitive DEGMA-modified hyaluronic acid hydrogel(THH)for the controlled release of Exos-miRNA 24-3p.It formed a highly uniform and clear thin layer on the ocular surface to resist clearance from blinking and extended the drug-ocular-epithelium contact time.The use of THH-3/Exos-miRNA 24-3p for 28 days after alkali burn injury accelerated corneal epithelial defect healing and epithelial maturation.It also reduced corneal stromal fibrosis and macrophage activation.MiRNA 24-3p-rich exosomes functionalized DEGMA-modified hyaluronic acid hydrogel as a multilevel delivery strategy has a potential use for cell-free therapy of corneal epithelial regeneration. 展开更多
关键词 miRNA 24-3p EXOSOME Corneal epithelium Cell migration Thermosensitive hydrogel
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Lung adenocarcinoma associated with cystic airspaces
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作者 Xue Yang Linlin Zhang +3 位作者 Fanlu Meng wenjing song Dong Li Diansheng Zhong 《Chronic Diseases and Translational Medicine》 CSCD 2023年第1期58-62,共5页
To the Editor,Lung cancer associated with cystic airspaces is a group of uncommon lung malignant lesions that are easy to misdiagnose even though the use of computed tomography(CT)has been more common for lung cancer ... To the Editor,Lung cancer associated with cystic airspaces is a group of uncommon lung malignant lesions that are easy to misdiagnose even though the use of computed tomography(CT)has been more common for lung cancer screening in the clinic.The incidence of this lesion has been reported at 0.5%–3.7%in different studies.1–3 Up to 80%of patients was of pulmonary adenocarcinomas and most patients had a history of smoking. 展开更多
关键词 LUNG ADENOCARCINOMA LUNG
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MicroRNA-activated hydrogel scaffold generated by 3D printing accelerates bone regeneration 被引量:2
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作者 Ting Pan wenjing song +5 位作者 Hongbao Xin Haiyue Yu He Wang Dandan Ma Xiaodong Cao Yingjun Wang 《Bioactive Materials》 SCIE 2022年第4期1-14,共14页
Bone defects remain a major threat to human health and bone tissue regeneration has become a prominent clinical demand worldwide.The combination of microRNA(miRNA)therapy with 3D printed scaffolds has always posed a c... Bone defects remain a major threat to human health and bone tissue regeneration has become a prominent clinical demand worldwide.The combination of microRNA(miRNA)therapy with 3D printed scaffolds has always posed a challenge.It can mimic physiological bone healing processes,in which a biodegradable scaffold is gradually replaced by neo-tissue,and the sustained release of miRNA plays a vital role in creating an optimal osteogenic microenvironment,thus achieving promising bone repair outcomes.However,the balance between two key factors-scaffold degradation behavior and miRNA release profile-on osteogenesis and bone formation is still poorly understood.Herein,we construct a series of miRNA-activated hydrogel scaffolds(MAHSs)generated by 3D printing with different crosslinking degree to screened the interplay between scaffold degradation and miRNA release in the osteoinduction activity both in vitro and in vivo.Although MAHSs with a lower crosslinking degree(MAHS-0 and MAHS-0.25)released a higher amount of miR-29b in a sustained release profile,they degraded too fast to provide prolonged support for cell and tissue ingrowth.On the contrary,although the slow degradation of MAHSs with a higher crosslinking degree(MAHS-1 and MAHS-2.5)led to insufficient release of miR-29b,their adaptable degradation rate endowed them with more efficient osteoinductive behavior over the long term.MAHS-1 gave the most well-matched degradation rate and miR-29b release characteristics and was identified as the preferred MAHSs for accelerated bone regeneration.This study suggests that the bio-adaptable balance between scaffold degradation behavior and bioactive factors release profile plays a critical role in bone regeneration.These findings will provide a valuable reference about designing miRNAs as well as other bioactive molecules activated scaffold for tissue regeneration. 展开更多
关键词 Bone repair microRNA therapy SCAFFOLD OSTEOGENESIS
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Corneal regeneration by utilizing collagen based materials 被引量:1
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作者 Xuan Zhao wenjing song +1 位作者 Sa Liu Li Ren 《Science China Chemistry》 SCIE EI CAS CSCD 2016年第12期1548-1553,共6页
Corneal disease is the main cause of blindness and keratoplasty is the only widely accepted treatment. Shortage of donor tissue makes the biomaterials for corneal regeneration a hot area of research. Collagen is the m... Corneal disease is the main cause of blindness and keratoplasty is the only widely accepted treatment. Shortage of donor tissue makes the biomaterials for corneal regeneration a hot area of research. Collagen is the main component of corneal stroma, so collagen becomes a promising material for corneal repair. However, due to the drawbacks of collagen, it needs to be further modified to satisfy the requirement of corneal regeneration. In this article, we highlight the importance of collagen materials for corneal repair, and summarize several methods of preparing collagen based corneal regeneration materials, including chemical crosslinking, plastic compression of collagen, and collagen vitrigel. These modification methods can make collagen membranes with remarkable properties such as enough mechanical and suture retention strength, antibacterial property and excellent optical property. These materials may provide potential treatment for corneal disease. 展开更多
关键词 角膜新生 骨胶原 织物工程 biomaterial
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Visualizing phase transition of upper critical solution temperature (UCST) polymers with AIE
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作者 Yong-Guang Jia Kai-Feng Chen +10 位作者 Meng Gao Sa Liu Jin Wang Xiaohui Chen Lin Wang Yunhua Chen wenjing song Huatang Zhang Li Ren Xiao-Xia Zhu Ben Zhong Tang 《Science China Chemistry》 SCIE EI CAS CSCD 2021年第3期403-407,共5页
The stimuli-responsive polymers with upper critical solution temperatures(UCST) are highly attractive for drug delivery applications. However, the phase transition process of UCST polymer is usually characterized by t... The stimuli-responsive polymers with upper critical solution temperatures(UCST) are highly attractive for drug delivery applications. However, the phase transition process of UCST polymer is usually characterized by turbidity measurement and electron microscopy, which are significantly restricted by low sensitivity and static observation. In contrary, the fluorescence technique has significant advantages in terms of high sensitivity, easy operation, and dynamic observation. However, the conventional fluorophores suffer from the drawbacks of aggregation-caused quenching(ACQ) after being encapsulated by UCST polymers, which are not suitable for direct visualization of the phase transition process. To tackle this challenge, we herein developed a series of UCST polymers based on polyacrylamides decorated with bile acid and aggregation-induced emission(AIE)-active tetraphenylethene(TPE) groups, which can be used for direct fluorescence monitoring of the phase transition process. Moreover, the AIE-active UCST polymers can serve as drug carriers, which can not only monitor the drug release process under thermal stimuli, but also verify the drug release by fluorescence recovery after thermal stimuli. It is expected that the AIE-active UCST polymers with self-monitoring ability are promising for biomedical applications. 展开更多
关键词 upper critical solution temperatures aggregation-induced emission phase transition process drug release monitoring bile acid
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基于核苷酸配合物的多级手性的研究进展
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作者 李晖 朱艳宏 +3 位作者 周培 仇启明 宋文静 谷磊磊 《中国科学:化学》 CAS CSCD 北大核心 2020年第9期947-961,共15页
手性是自然界中普遍存在的一种特殊对称性.生物体展示了跨多尺度的手性信息与传递的功能.研究多级手性的传递、诱导与放大是涉及化学、生物、物理、材料等多个学科的基本科学问题.从分子手性到宏观手性可在不同的长度与尺度下分为四个层... 手性是自然界中普遍存在的一种特殊对称性.生物体展示了跨多尺度的手性信息与传递的功能.研究多级手性的传递、诱导与放大是涉及化学、生物、物理、材料等多个学科的基本科学问题.从分子手性到宏观手性可在不同的长度与尺度下分为四个层级:构型(分子)手性(一级)、构象手性(二级)、相手性(三级)、宏观手性(四级).基于核苷酸配位超分子组装体的X射线单晶结构研究并结合固(晶)态圆二色谱分析方法是研究多级手性问题的有效途径.深刻认识与理解多尺度的手性组装、手性诱导与手性传递不仅有助于我们认识生物体的结构与功能的关系,而且还为合理设计与合成手性功能材料与人工分子机器提供理论基础.本文基于本课题组在核苷酸手性配位超分子组装体方面的研究成果,阐述了一种有效研究构象手性与相手性的方法,即X射线单晶衍射技术与固态圆二色光谱相关联的手性研究方法.首次将有机化学中的轴手性拓展至一维配位聚合物中而创新地提出“拓展轴手性”的概念.在精确晶体结构数据分析的基础上,揭示了金属配位键、氢键、π-π堆积作用等在手性诱导、手性组装和手性传递等方面的作用.同时,对未来手性研究提出了展望. 展开更多
关键词 手性 晶体结构 圆二色谱 配位超分子组装体 核苷酸
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