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A Case Study on the Effectiveness of Pre-Class Activities in Higher Vocational English Classes: Taking Pingliang Vocational and Technical College as an Example
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作者 Liuna Yang 《Journal of Contemporary Educational Research》 2024年第8期233-237,共5页
Based on Bloom’s“effective teaching theory,”this paper proposes pre-class activities to improve students’enthusiasm and autonomy in English learning.These include sentence construction,situational dubbing,famous q... Based on Bloom’s“effective teaching theory,”this paper proposes pre-class activities to improve students’enthusiasm and autonomy in English learning.These include sentence construction,situational dubbing,famous quotes,English songs,English games,Chinese stories,regional cultures,and theme debates,which combine life,interest,and inspiration as the main characteristics.The activities can enhance the sense of participation and achievement of all students to achieve the purpose of effective teaching. 展开更多
关键词 Higher vocational college English class Pre-class activity EFFECTIVENESS
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Visualization for Explanation of Deep Learning-Based Defect Detection Model Using Class Activation Map 被引量:1
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作者 Hyunkyu Shin Yonghan Ahn +3 位作者 Mihwa Song Heungbae Gil Jungsik Choi Sanghyo Lee 《Computers, Materials & Continua》 SCIE EI 2023年第6期4753-4766,共14页
Recently,convolutional neural network(CNN)-based visual inspec-tion has been developed to detect defects on building surfaces automatically.The CNN model demonstrates remarkable accuracy in image data analysis;however... Recently,convolutional neural network(CNN)-based visual inspec-tion has been developed to detect defects on building surfaces automatically.The CNN model demonstrates remarkable accuracy in image data analysis;however,the predicted results have uncertainty in providing accurate informa-tion to users because of the“black box”problem in the deep learning model.Therefore,this study proposes a visual explanation method to overcome the uncertainty limitation of CNN-based defect identification.The visual repre-sentative gradient-weights class activation mapping(Grad-CAM)method is adopted to provide visually explainable information.A visualizing evaluation index is proposed to quantitatively analyze visual representations;this index reflects a rough estimate of the concordance rate between the visualized heat map and intended defects.In addition,an ablation study,adopting three-branch combinations with the VGG16,is implemented to identify perfor-mance variations by visualizing predicted results.Experiments reveal that the proposed model,combined with hybrid pooling,batch normalization,and multi-attention modules,achieves the best performance with an accuracy of 97.77%,corresponding to an improvement of 2.49%compared with the baseline model.Consequently,this study demonstrates that reliable results from an automatic defect classification model can be provided to an inspector through the visual representation of the predicted results using CNN models. 展开更多
关键词 Defect detection VISUALIZATION class activation map deep learning EXPLANATION visualizing evaluation index
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Synthesis and Antitumor Activity of 3-[2-(4-Hydroxy-Phenyl)-Ethyl]-Benzo[d] Isoxazole-4,6-Diol
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作者 Li Wang 《International Journal of Organic Chemistry》 CAS 2023年第1期1-6,共6页
A new phloretin derivative 1 3-[2-(4-hydroxy-phenyl)-ethyl]-benzo[d] isoxazole-4,6-diol (yield 63%) was synthesized from phloretin by carbonyl nucleophilic addition condensation reaction. Its structure was characteriz... A new phloretin derivative 1 3-[2-(4-hydroxy-phenyl)-ethyl]-benzo[d] isoxazole-4,6-diol (yield 63%) was synthesized from phloretin by carbonyl nucleophilic addition condensation reaction. Its structure was characterized by 1H NMR, 13C NMR and HR-MS. The phloretin, compound 1, resveratrol and acetylated resveratrol were determined by comparing them with paclitaxel. Anti-tumor activity of alcohol on SPC-A1, EC109, A549, MCF-7 and MDA-MB-231 cell lines. Compound 1 showed better antitumor activity than docetaxel against A549 tumor cells. 展开更多
关键词 3-[2-(4-Hydroxy-Phenyl)-Ethyl]-Benzo[d] Isoxazole-4 6-Diol SYNTHESIS Antitumor activity
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Synthesis, Structural Characterization and Antimicrobial Activity of a Novel Cobalt(II) Complex Based on 3-Methyl-1-Phenyl-4-(2-Thienoyl)-Pyrazol-5-One
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作者 Emeline Sorelle Mefouegang Claudelle Sybilline Anensong Djadock +5 位作者 Golngar Djimassingar Gabriel Tchuente Kamsu Donald Raoul Tchuifon Tchuifon Alain Charly Tagne Kuate Dirk Bockfeld Jean Ngoune 《Journal of Materials Science and Chemical Engineering》 2023年第8期109-126,共18页
New cobalt(II) complex, [Co(O<sub>2</sub>C<sub>15</sub>H<sub>11</sub>N<sub>2</sub>S)<sub>2</sub>(OH<sub>2</sub>)<sub>2</sub>]∙2H<s... New cobalt(II) complex, [Co(O<sub>2</sub>C<sub>15</sub>H<sub>11</sub>N<sub>2</sub>S)<sub>2</sub>(OH<sub>2</sub>)<sub>2</sub>]∙2H<sub>2</sub>O (1∙2H<sub>2</sub>O), has been synthesized upon reaction of cobalt chloride hexahydrate (Co(Cl)<sub>2</sub>∙6H<sub>2</sub>O) with 3-methyl-1-Phenyl-4-(2-thienoyl)-pyrazol-5-one (referred as HL) in ethanol at room temperature. Single crystal X-ray diffraction (XRD), spectroscopic methods, and microelemental analyses were used to characterize 1∙2H<sub>2</sub>O. Compound 1∙2H<sub>2</sub>O crystallizes in the orthorhombic crystal system with a Pbca space group and with the cobalt atom being pseudo-octahedral coordinated. The broth microdilution technique was used to screen the free ligand (HL) and the complex (1∙2H<sub>2</sub>O) for antimicrobial activities. HL has a low activity (MIC > 100 μg/mL) on all microorganisms, whereas compound 1∙2H<sub>2</sub>O displayed moderate activity (10 ∙2H<sub>2</sub>O exhibited bactericidal and fungicidal activity respectively on all the bacteria and yeasts tested. These findings reveal that the antimicrobial activity of HL was enhanced upon coordination to Co(II) ion against all microorganisms (bacteria and fungus). 展开更多
关键词 COBALT ACYLPYRAZOLONE X-Ray Diffraction Antimicrobial activity 3-Methyl-1-Phenyl-4-(2-Thienoyl)-Pyrazol-5-One
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Synthesis, Structural Characterization and Antimicrobial Activity of a Novel Cobalt(II) Complex Based on 3-Methyl-1-Phenyl-4-(2-Thienoyl)-Pyrazol-5-One
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作者 Emeline Sorelle Mefouegang Claudelle Sybilline Anensong Djadock +5 位作者 Golngar Djimassingar Gabriel Tchuente Kamsu Donald Raoul Tchuifon Tchuifon Alain Charly Tagne Kuate Dirk Bockfeld Jean Ngoune 《Journal of Modern Physics》 2023年第8期109-126,共12页
New cobalt(II) complex, [Co(O<sub>2</sub>C<sub>15</sub>H<sub>11</sub>N<sub>2</sub>S)<sub>2</sub>(OH<sub>2</sub>)<sub>2</sub>]∙2H<s... New cobalt(II) complex, [Co(O<sub>2</sub>C<sub>15</sub>H<sub>11</sub>N<sub>2</sub>S)<sub>2</sub>(OH<sub>2</sub>)<sub>2</sub>]∙2H<sub>2</sub>O (1∙2H<sub>2</sub>O), has been synthesized upon reaction of cobalt chloride hexahydrate (Co(Cl)<sub>2</sub>∙6H<sub>2</sub>O) with 3-methyl-1-Phenyl-4-(2-thienoyl)-pyrazol-5-one (referred as HL) in ethanol at room temperature. Single crystal X-ray diffraction (XRD), spectroscopic methods, and microelemental analyses were used to characterize 1∙2H<sub>2</sub>O. Compound 1∙2H<sub>2</sub>O crystallizes in the orthorhombic crystal system with a Pbca space group and with the cobalt atom being pseudo-octahedral coordinated. The broth microdilution technique was used to screen the free ligand (HL) and the complex (1∙2H<sub>2</sub>O) for antimicrobial activities. HL has a low activity (MIC > 100 μg/mL) on all microorganisms, whereas compound 1∙2H<sub>2</sub>O displayed moderate activity (10 ∙2H<sub>2</sub>O exhibited bactericidal and fungicidal activity respectively on all the bacteria and yeasts tested. These findings reveal that the antimicrobial activity of HL was enhanced upon coordination to Co(II) ion against all microorganisms (bacteria and fungus). 展开更多
关键词 COBALT ACYLPYRAZOLONE X-Ray Diffraction Antimicrobial activity 3-Methyl-1-Phenyl-4-(2-Thienoyl)-Pyrazol-5-One
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Exploration of the Role-Playing Model in Primary School Class Activities Under the Background of“Class Activity Month”
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作者 Siliang Yu 《Journal of Contemporary Educational Research》 2021年第11期167-170,共4页
Education in the new era advocates taking students as the main body and improving students’core literacy on this basis.Subjectivity has also become one of the keys to quality education.Primary school is not only the ... Education in the new era advocates taking students as the main body and improving students’core literacy on this basis.Subjectivity has also become one of the keys to quality education.Primary school is not only the initial stage of life,but also the key period to develop students’subjectivity.At present,there are many problems in class activities,such as the weak concept of taking students as the main body,the lack of subject consciousness among students,the flawed construction system of class activities,the unreasonable evaluation system of class activities,and so on.By establishing the role-playing model under the background of“class activity month,”students can play different roles in class activities and participate in various links,such as theme selection,scheme design,organization,implementation,summary,and evaluation of class activities.Through this process,it does not only improve the quality of class activities,but also cultivate students’subject consciousness and ability in a certain subject,thus highlighting their subject status in class activities. 展开更多
关键词 class activity month Role-playing model class activity in primary school
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Expression, Purification and Insecticidal Activity Analysis of Cry1Ac without Helix α-1
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作者 刘京国 郭蓓 +1 位作者 赵晓萌 师光禄 《Agricultural Science & Technology》 CAS 2012年第2期265-267,303,共4页
[Objective] This study aimed to analyze the expression, purification and insecticidal activity of Cry1Ac without helix α-1 of domain I in E. coli. [Method] Plasmid of B. thuringiensis HD-1 was used as the template fo... [Objective] This study aimed to analyze the expression, purification and insecticidal activity of Cry1Ac without helix α-1 of domain I in E. coli. [Method] Plasmid of B. thuringiensis HD-1 was used as the template for amplification of Cry1Ac gene, which was linked with pET28a vector to construct the recombinant plasmid. After transformation and IPTG induction, expression of target protein was detected by using SDS-PAGE method. Target protein was extracted and coated on the surface of feed for H. armigera to determine the insecticidal activity. [Result] Cry1Acdela1 gene could normally express the target protein in E. coli. However, the target protein existed in the form of inclusion body. Results of bioassay analysis showed that under the same concentration, fatality rate of activated Cry1Ac toxin reached above 75%, while that of Cry1Acdelα1 was only about 10%. [Conclusion] E. coli-expressed Cry1Acdelα1 had no insecticidal activity against H. armigera. 展开更多
关键词 CRY1AC α-1 fragment Insecticidal activity
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The Application of Goal-Setting Theory in the Second Classroom Teaching Activities of College English
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作者 宋琳琳 胡春华 《英语广场(学术研究)》 2012年第5期93-95,共3页
Interest is the precondition and motivation for people's accomplishment.However,due to the exam-oriented system,millions of parents and teachers neglect the interests of children,and our children nearly forget the... Interest is the precondition and motivation for people's accomplishment.However,due to the exam-oriented system,millions of parents and teachers neglect the interests of children,and our children nearly forget their interests or hobbies.Based on different interests of children,the thesis analyzes how to apply the goal-setting theory in the second classroom teaching activities of College English,using the example of Lushan College of Guangxi University of Technology. 展开更多
关键词 goal-setting theory second class teaching activities College English
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A Pair of New Spirocyclic Alkaloid Enantiomers with TrxR Inhibitory Activities Were Isolated from Marine-Derived Aspergillus ruber TX-M4-1 被引量:1
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作者 WANG Cong WANG Yufei +4 位作者 SUN Jian WANG Shiyi DU Weisheng ZHOU Liman KONG Fandong 《Journal of Ocean University of China》 SCIE CAS CSCD 2023年第6期1677-1682,共6页
One new spirocyclic alkaloid,5-isopentenyl-cryptoechinuline D(1),along with 11 known compounds(2–12),were iso-lated from a marine fungus Aspergillus ruber TX-M4-1.The structures of compounds 1–12 were elucidated by ... One new spirocyclic alkaloid,5-isopentenyl-cryptoechinuline D(1),along with 11 known compounds(2–12),were iso-lated from a marine fungus Aspergillus ruber TX-M4-1.The structures of compounds 1–12 were elucidated by spectroscopic evi-dences.Compound 1 was initially isolated as an enantiomer,and further separation of 1 by chiral HPLC afforded a pair of enantio-mers,including(-)-5-isopentenyl-cryptoechinuline D(1a)and(+)-5-isopentenyl-cryptoechinuline D(1b).Their absolute configura-tions were elucidated by ECD spectroscopic data.Compounds 1a,5 and 10 could inhibit thioredoxin reductase(TrxR)activity with IC50 values of 6.2,36.3 and 18.6μmol L^(-1),respectively.Surface plasmon resonance(SPR)study also demonsrated the interactions between compounds 6,8 and Niemann-Pick C1 Like 1(NPC1L1)respectively,which indicate that compounds 6 and 8 are potential NPC1L1 inhibitors. 展开更多
关键词 Aspergillus ruber TX-M4-1 spirocyclic alkaloid TrxR inhibitory activity
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Activity budgets in a group of Sichuan snub-nosed monkeys in Shennongjia Nature Reserve,China 被引量:3
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作者 Yiming LI 《Current Zoology》 SCIE CAS CSCD 北大核心 2009年第3期173-179,共7页
We examined time allocation by Sichuan snub-nosed monkeys Rhinopithecus roxellana in the montane, temperate and highly seasonal forests of the Shennongjia Nature Reserve in China, in order to improve our understanding... We examined time allocation by Sichuan snub-nosed monkeys Rhinopithecus roxellana in the montane, temperate and highly seasonal forests of the Shennongjia Nature Reserve in China, in order to improve our understanding of the ecological and social influences on monkey behavior. We collected data on activity budgets in relation to food availability in a group of monkeys from July 2003 to September 2004 (except February 2004), using instantaneous scan samples. The monkeys spent 36.21% of daytime moving ( n = 21, 269 records), 24.39% foraging, 9.33% inactive, 11,7% performing social behaviors, and 18.38% performing other behaviors. There were seasonal and annual variations in the proportions of time devoted to some activities. These variations were largely attributed to seasonal or annual fluctuations in the distribution and quality of food resources. Adult males spent more time moving, searching, and displaying other behaviors, but less time feeding and performing social behaviors than adult females. Adults performed other behaviors more often and moving less often than juveniles. These differences in activity budgets may reflect fundamental differences in reproductive biology, parental investment, and development among the different age/sex classes [ Current Zoology 55 (3) : 173 - 179, 2009] . 展开更多
关键词 activity budgets Seasonal food availability Age/sex classes Sichuan snub-nosed monkeys Rhinopithecus roxellana
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基于深度学习算法联合Grad-CAM的宫腔镜子宫内膜病变诊断模型研究
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作者 曹明亮 尹蜜 +9 位作者 王庆彬 朱汉峰 李星 张珺 毛林 穆雪峰 曹敏 马于涛 王健 张燕 《实用妇产科杂志》 CAS CSCD 北大核心 2024年第5期409-413,共5页
目的:探讨基于深度学习(DL)算法联合可视化技术梯度加权类激活热图(Grad-CAM)开发的宫腔镜子宫内膜病变诊断模型的有效性。方法:选择2021年6月1日至2022年12月31日在武汉大学人民医院妇科行宫腔镜检查的291例患者的303段宫腔镜视频(478... 目的:探讨基于深度学习(DL)算法联合可视化技术梯度加权类激活热图(Grad-CAM)开发的宫腔镜子宫内膜病变诊断模型的有效性。方法:选择2021年6月1日至2022年12月31日在武汉大学人民医院妇科行宫腔镜检查的291例患者的303段宫腔镜视频(4781张图像),采用权重采样的方法,将数据集划分为训练集(3703张)和测试集(1078张)。在对训练集用于模型学习与训练后,选择残差神经网络(ResNet18)和高效神经网络(EfficientNet-B0)两种模型架构对测试集分别采用五类和二类分类任务进行模型验证。以病理组织学为金标准,评估其诊断效能,从而选出最优模型,并将Grad-CAM层嵌入最优模型中,输出宫腔镜图像Grad-CAM。结果:①在五类分类任务中,EfficientNet-B0模型的准确度(93.23%)高于ResNet18模型(84.23%);EfficientNet-B0模型在诊断无不典型性子宫内膜增生、子宫内膜息肉、子宫内膜癌、子宫内膜非典型增生、黏膜下肌瘤5种疾病的曲线下面积(AUC)均稍高于ResNet18模型,两者的AUC几乎都在0.980以上。②在准确度的二类分类任务中和对特异度的评估中,两种模型相似,均在93.00%以上,而EfficientNet-B0模型敏感度(91.14%)明显优于ResNet18模型(77.22%)。③EfficientNet-B0模型联合Grad-CAM算法可识别出图像中异常区域,取活检经病理检查证实,模型输出热力图中标记区域约95%为病灶区域。结论:EfficientNet-B0模型联合Grad-CAM研发的宫腔镜诊断模型具有较高的诊断准确度、敏感度和特异度,在诊断子宫内膜病变方面具有应用价值。 展开更多
关键词 宫腔镜 子宫内膜癌 卷积神经网络 梯度加权类激活热图 深度学习
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Activity of the Fungicide JS399-19 Against Fusarium Head Blight of Wheat and the Risk of Resistance 被引量:7
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作者 CHEN Yu WANG Wen-xiang +3 位作者 ZHANG Ai-fang GU Chun-yan ZHOU Ming-guo GAO Tong-chun 《Agricultural Sciences in China》 CAS CSCD 2011年第12期1906-1913,共8页
This report reviews the characteristics of JS399-19, a novel cyanoacrylate fungicide. JS399-19 strongly inhibits the mycelial growth of the fungal plant pathogens of the genus Fusarium and exhibits great potential in ... This report reviews the characteristics of JS399-19, a novel cyanoacrylate fungicide. JS399-19 strongly inhibits the mycelial growth of the fungal plant pathogens of the genus Fusarium and exhibits great potential in controlling Fusarium head blight (FHB) on wheat and other cereals. The mode of action of JS399-19 is evidently different from that of benzimidazole (for example, carbendazim) and other sort of fungicides, making it a possible replacement for carbendazim in China to manage carbendazim-resistant subpopulations of Fusarium graminearum and F. asiaticum. JS399-t9 has excellent protective and curative activity against these pathogens. Incorrect use of this fungicide, however, is likely to select for resistance. Among JS399-19-resistant mutants of F. asiaticum induced in the laboratory, the resistant level of mutants was high and the phenotype of resistance against JS399-19 was conferred by a major gene by genetic analysis. The fitness of laboratory-induced JS399-19-resistant mutants of F. asiaticum was nearly equal to that of their parents. JS399-19 lacks cross resistance with other sort fungicides. To control FHB with JS399-19 and to delay the development of the fungicide-resistance, farmers should use tank mixtures containing JS399-19 and carbendazim, metconazole, tebuconazole, or prothioconazole. 展开更多
关键词 fungicide JS399-19 cyanoacrylate fungicide Fusarium head blight activity resistance risk
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Calculation of Activity Coefficients for Components in Ti-15-3 Melt 被引量:3
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作者 苏彦庆 刘源 +2 位作者 郭景杰 贾均 丁宏升 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 1999年第1期54-57,共4页
Based on Kohler’s ternary solution model and Miedemaa’s model for calculating the heats of formation-△Hij of binary Systems, the integral equation has ben established for calculating the activity coefficients in te... Based on Kohler’s ternary solution model and Miedemaa’s model for calculating the heats of formation-△Hij of binary Systems, the integral equation has ben established for calculating the activity coefficients in ternarysolution. With the equation, the activity coefficients in Ti-15-3 melt have been calculated. The results show that allof components’ activity coefficients are less than 1, in other wolds, compared with ideal solution, all components takeon a negative deviation. At 2000K, the activity coefficients in Ti-15-3 melt are shown as: about 0.9 for Ti, about0.85 for V, about 0. 1 for Al, aboaut 0.5 for Cr and about 0.23 for Sn. me addition of V lowers the activity coefficient of Ti, but raise the ones of Al, Cr and Sn. These results can be directly used to calculate the evaporation loss ofAl, Cr and Sn during the ISM(Induction Skull Melting) process and at the same time estimate the reactivity betweenTi-15-3 melt and refractory during the cast production. 展开更多
关键词 activity COEFFICIENT Ti-15-3 alloy ISM process
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Ensemble-based active learning for class imbalance problem 被引量:1
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作者 Yanping Yang Guangzhi Ma 《Journal of Biomedical Science and Engineering》 2010年第10期1022-1029,共8页
In medical diagnosis, the problem of class imbalance is popular. Though there are abundant unlabeled data, it is very difficult and expensive to get labeled ones. In this paper, an ensemble-based active learning algor... In medical diagnosis, the problem of class imbalance is popular. Though there are abundant unlabeled data, it is very difficult and expensive to get labeled ones. In this paper, an ensemble-based active learning algorithm is proposed to address the class imbalance problem. The artificial data are created according to the distribution of the training dataset to make the ensemble diverse, and the random subspace re-sampling method is used to reduce the data dimension. In selecting member classifiers based on misclassification cost estimation, the minority class is assigned with higher weights for misclassification costs, while each testing sample has a variable penalty factor to induce the ensemble to correct current error. In our experiments with UCI disease datasets, instead of classification accuracy, F-value and G-means are used as the evaluation rule. Compared with other ensemble methods, our method shows best performance, and needs less labeled samples. 展开更多
关键词 class IMBALANCE active learning ENSEMBLE RANDOM SUBSPACE MISclassIFICATION COST
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Characterization and Anti-tumor Activity of Glycopeptides from Ganoderma sinensis 被引量:5
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作者 GAO Yang JIANG Ru-zhi +3 位作者 CHEN Ying-hong LUO Hao-ming XU Duo-duo GAO Qi-pin 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2009年第1期47-51,共5页
The water-soluble part(GS) of Ganoderma sinense Zhao, Xu et Zhang was divided into high molecular(GS-H) and low molecular(GS-L) parts by Cellulose Super Filtration, and GS was also fractionated into four fractio... The water-soluble part(GS) of Ganoderma sinense Zhao, Xu et Zhang was divided into high molecular(GS-H) and low molecular(GS-L) parts by Cellulose Super Filtration, and GS was also fractionated into four fractions, GS-1, 2, 3, and 4 by ethanol precipitation according to their molecular weights. Chemical analysis shows that GS and GS-1, 2, 3, 4 were complexes of polysaccharide and peptide. The fractions with molecular weights over 4000, GS-1, 2, 3, and GS-H show anti-tumor activities, however, the fractions with molecular weights lower than 4000, GS-4, and GS-L have no anti-tumor activity, indicating that the anti-tumor activity of Ganoderma Sinensis was caused by glucopeptides with molecular weight ranging from 4000 to 20000. Two purified glucopeptides, GS-6b and GS-7b were obtained from GS-H by ion-exchange and gel-permeation chromatography. Their molecular weights, glycosidic linkages, and configurations were detected by means of IR spectrum, sugar composition analysis, and methylation analysis. The polysaccharide parts of GS-6b and GS-7b had glucan backbone consisting of β-1→3 Glc, and side chain containing glucosyl, mannosyl, fucosyl, xylosyl, galactosyl, and glucuronic acid residues attached on 1-2, 1-4, 1-6 positions of the backbone of GS-6b, or 1-6, 1-4 positions of the backbone of GS-7b. The peptide parts in GS-6b and GS-7b were composed of 10 kinds of amino acids, including Asp, Ser, Arg, Gly, Thr, Pro, Ala, Val, Met, and Lys. 展开更多
关键词 Ganoderma sinense Zhao Xu et Zhang Anti-tumor activity Glucopeptide β- 1→3 glucan
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Synthesis, Crystal Structure and Antitumor Activity of (E)-4-tert-Butyl-N-(2,4-dichlorobenzylidene)-5-(1,2,4-triazol-1-yl)-thiazol-2-amine 被引量:5
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作者 胡艾希 覃智 +1 位作者 叶姣 夏曙 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2010年第11期1680-1683,共4页
The title compound (E)-4-tert-butyl-N-(2,4-dichlorobenzylidene)-5-(1,2,4-triazol-1-yl)-thiazol-2-amine was synthesized by the reaction of 4-tert-butyl-5-(1,2,4-triazol-1-yl)-thiazol-2-amine with 2,4-dichlorobe... The title compound (E)-4-tert-butyl-N-(2,4-dichlorobenzylidene)-5-(1,2,4-triazol-1-yl)-thiazol-2-amine was synthesized by the reaction of 4-tert-butyl-5-(1,2,4-triazol-1-yl)-thiazol-2-amine with 2,4-dichlorobenzaldehyde, and its crystal structure was determined by singlecrystal X-ray diffraction. The crystal belongs to the triclinic system, space group P1 with a = 7.9748(4), b = 10.1803(5), c = 11.4603(6), α = 102.882(1), β = 100.253(1), γ = 104.457(1)°, V = 850.95(7)3, Z = 2, F(000) = 392, C16H15Cl2N5S, Mr = 380.29, Dc = 1.484 g/cm3, S = 1.095, μ = 0.512 mm-1, the final R = 0.0301 and wR = 0.0965 for 3334 observed reflections (I 〉 2σ(I)). The preliminary antitumor activity shows that for the title compound the IC50 of Hela is 0.175 μmol/mL and that of Bel7402 is 0.156 μmol/mL. 展开更多
关键词 (E)-4-tert-butyl-N-(2 4-dichorobenzylidene)-5-(1 2 4-triazl-1-yl)-thiazol-2-amine crystal structure synthesis antitumor activity
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Synthesis, Crystal Structure and Fungicidal Activity of N-(4-tert-buty)-5-(1,2,4-triazol-1-yl)thiazol-2-yl)propionamide 被引量:3
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作者 叶姣 孙晓潇 +1 位作者 邱慎意 胡艾希 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2014年第3期429-433,共5页
The title compound has been synthesized by the reaction of 4-tert-butyl-5-(1,2,4- triazol-1-yl)-2-aminothiazole with propionic anhydride, and its crystal structure was determined by single-crystal X-ray diffraction.... The title compound has been synthesized by the reaction of 4-tert-butyl-5-(1,2,4- triazol-1-yl)-2-aminothiazole with propionic anhydride, and its crystal structure was determined by single-crystal X-ray diffraction. The crystal belongs to the orthorhombic system, space group Pbca with α = 18.441(2), b = 8.3284(9), c = 19.257(2) A, Z = 8, V = 2957.5(5) A3, Mr = 279.37, Dc = 1.255 mg/m3, S = 1.033, μ =0.219 mm^-1, F(000) = 1184, the final R = 0.0349 and wR = 0.0876 for 2629 observed reflections (I 〉 2σ(I)). X-ray crystal structure presents the intermolecular N–H···N hydrogen bond, which plays an important role in stabilizing the crystal structure. The preliminary bioassay indicates that the title compound exhibits potent fungicidal activity against R. Solani (25 mg/L) with inhibition rate of 80.0%. 展开更多
关键词 N- 4-tert-buty)-5-(1 2 4-triazoi- l-yl)thiazol-2-yl)propionamide SYNTHESIS crystal structure fungicidal activity
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Studies on Condensed Heterocyclic Compounds(Ⅲ)——Synthesis and Antibacterial Activity of 3-(4-Pyridyl)-6-Alkyl/Aromatic Heterocyclyl-s-Triazolo[3,4-b]-1, 3,4-Thiadiazoles and 1,4-Bis [6-(4-Pyridyl)-s-Triazolo [3,4-b]-1, 3,4-Thiadiazol-3-yl]-n-Butane 被引量:2
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作者 Zhang Ziyi, Chen Xin, Wei Lulin and Ma Zhaoli (Department, of Chemistry, Lanzhou University, Lanzhou) 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 1991年第2期129-133,共5页
In recent years, fused heterocycles have been reported to possess important properties in synthesis and pharmacology. Especially, s-triazolo, 3,4-thiadiazole derivatives have been attracting much attention for chemist... In recent years, fused heterocycles have been reported to possess important properties in synthesis and pharmacology. Especially, s-triazolo, 3,4-thiadiazole derivatives have been attracting much attention for chemists and pharmacologists because they show broad spectra of biological activities, such as antifungal, antibacterial, hy- 展开更多
关键词 s-Triazolo[3 4-b]-1 3 4-thiadiazoles SYNTHESIS Antibacterial activity
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Synthesis,Crystal Structure and Antitumor Activity of N-(4-tert-butyl-5-(4-chlorobenzyl)thiazol-2-yl)-2,6-difluorobenzamide 被引量:2
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作者 申坤 彭俊梅 +2 位作者 李婉 颜晓维 胡艾希 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2014年第6期855-858,共4页
The title compound was synthesized by the reaction of 4-tert-butyl-5-(4-chlorobenzyl)-2-aminothiazole with 2,6-difluorobenzoic acid. The crystal structure of the title compound, C21H19ClF2N2OS, was determined by sin... The title compound was synthesized by the reaction of 4-tert-butyl-5-(4-chlorobenzyl)-2-aminothiazole with 2,6-difluorobenzoic acid. The crystal structure of the title compound, C21H19ClF2N2OS, was determined by single-crystal X-ray diffraction. The crystal belongs to the triclinic system, space group Pbca with a = 12.6479(13), b = 13.1204(13), c = 14.1341(15), Z = 4, V = 2011.5(4)3, Mr = 420.89, Dc = 1.390 g/cm3, S = 1.023, μ = 0.326 mm-1, F(000) = 872, the final R = 0.0365 and wR = 0.0880 for 6101 observed reflections(I 〉 2σ(I)), and R = 0.0507, wR = 0.0978 for 7779 independent reflections. X-ray crystal structure displays that the hydrogen bonding interactions observed link the molecules to form a dimeric unit. The preliminary biological test of the title compound shows good antitumor activity, with IC50 of 0.046 μmol/mL against the Hela cell line. 展开更多
关键词 N-(4-tert-butyl-5-(4-chlorobenzyl)thiazol-2-yl)-2 6-difluorobenzamide SYNTHESIS crystal structure antitumor activity
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18β-glycyrrhetinic acid promotes gastric cancer cell autophagy and inhibits proliferation by regulating miR-328-3p/signal transducer and activator of transcription 3
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作者 Yi Yang Yi Nan +7 位作者 Yu-Hua Du Shi-Cong Huang Dou-Dou Lu Jun-Fei Zhang Xia Li Yan Chen Lei Zhang Ling Yuan 《World Journal of Gastroenterology》 SCIE CAS 2023年第27期4317-4333,共17页
BACKGROUND Gastric cancer(GC)is one of the most common cancer types worldwide,and its prevention and treatment methods have garnered much attention.As the active ingredient of licorice,18β-glycyrrhetinic acid(18β-GR... BACKGROUND Gastric cancer(GC)is one of the most common cancer types worldwide,and its prevention and treatment methods have garnered much attention.As the active ingredient of licorice,18β-glycyrrhetinic acid(18β-GRA)has a variety of pharmacological effects.The aim of this study was to explore the effective target of 18β-GRA in the treatment of GC,in order to provide effective ideas for the clinical prevention and treatment of GC.AIM To investigate the mechanism of 18β-GRA in inhibiting cell proliferation and promoting autophagy flux in GC cells.METHODS Whole transcriptomic analyses were used to analyze and screen differentially expressed microRNAs(miRNAs)in GC cells after 18β-GRA intervention.Lentivirus-transfected GC cells and the Cell Counting Kit-8 were used to detect cell proliferation ability,cell colony formation ability was detected by the clone formation assay,and flow cytometry was used to detect the cell cycle and apoptosis.A nude mouse transplantation tumor model of GC cells was constructed to verify the effect of miR-328-3p overexpression on the tumorigenicity of GC cells.Tumor tissue morphology was observed by hematoxylin and eosin staining,and microtubule-associated protein light chain 3(LC3)expression was detected by immunohistochemistry.TransmiR,STRING,and miRWalk databases were used to predict the relationship between miR-328-3p and signal transducer and activator of transcription 3(STAT3)-related information.Expression of STAT3 mRNA and miR-328-3p was detected by quantitative polymerase chain reaction(qPCR)and the expression levels of STAT3,phosphorylated STAT3(p-STAT3),and LC3 were detected by western blot analysis.The targeted relationship between miR-328-3p and STAT3 was detected using the dual-luciferase reporter gene system.AGS cells were infected with monomeric red fluorescent protein-green fluorescent protein-LC3 adenovirus double label.LC3 was labeled and autophagy flow was observed under a confocal laser microscope.RESULTS The expression of miR-328-3p was significantly upregulated after 18β-GRA intervention in AGS cells(P=4.51E-06).Overexpression of miR-328-3p inhibited GC cell proliferation and colony formation ability,arrested the cell cycle in the G0/G1 phase,promoted cell apoptosis,and inhibited the growth of subcutaneous tumors in BALB/c nude mice(P<0.01).No obvious necrosis was observed in the tumor tissue in the negative control group(no drug intervention or lentivirus transfection)and vector group(the blank vector for lentivirus transfection),and more cells were loose and necrotic in the miR-328-3p group.Bioinformatics tools predicted that miR-328-3p has a targeting relationship with STAT3,and STAT3 was closely related to autophagy markers such as p62.After overexpressing miR-328-3p,the expression level of STAT3 mRNA was significantly decreased(P<0.01)and p-STAT3 was downregulated(P<0.05).The dual-luciferase reporter gene assay showed that the luciferase activity of miR-328-3p and STAT33’untranslated regions of the wild-type reporter vector group was significantly decreased(P<0.001).Overexpressed miR-328-3p combined with bafilomycin A1(Baf A1)was used to detect the expression of LC3 II.Compared with the vector group,the expression level of LC3 II in the overexpressed miR-328-3p group was downregulated(P<0.05),and compared with the Baf A1 group,the expression level of LC3 II in the overexpressed miR-328-3p+Baf A1 group was upregulated(P<0.01).The expression of LC3 II was detected after intervention of 18β-GRA in GC cells,and the results were consistent with the results of miR-328-3p overexpression(P<0.05).Additional studies showed that 18β-GRA promoted autophagy flow by promoting autophagosome synthesis(P<0.001).qPCR showed that the expression of STAT3 mRNA was downregulated after drug intervention(P<0.05).Western blot analysis showed that the expression levels of STAT3 and p-STAT3 were significantly downregulated after drug intervention(P<0.05).CONCLUSION 18β-GRA promotes the synthesis of autophagosomes and inhibits GC cell proliferation by regulating the miR-328-3p/STAT3 signaling pathway. 展开更多
关键词 18β-glycyrrhetinic acid miR-328-3p Signal transducer and activator of transcription 3 Cell proliferation Autophagy flow
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