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罗马直立生菜生长发育及营养指标对臭氧浓度升高和持续熏蒸的响应

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生态学报 2024年第14期44卷 6276-6287页

作者：刘颖宋蕊王效科高艺芹冯美琪翟欣月万五星河北师范大学生命科学学院石家庄050024 中国科学院生态环境研究中心城市与区域生态国家重点实验室北京100085

环境臭氧(O_(3))已成为影响植物生长发育的重要生态因子。为探究地面O_(3)污染对蔬菜形态学特征及营养指标的影响,选罗马直立生菜(Lactuca sativa ***)为实验材料,采用开顶式气室开展熏蒸实验。实验设置4个O_(3)熏蒸浓度(NF:未过滤的环... 详细信息

环境臭氧(O_(3))已成为影响植物生长发育的重要生态因子。为探究地面O_(3)污染对蔬菜形态学特征及营养指标的影响,选罗马直立生菜(Lactuca sativa ***)为实验材料,采用开顶式气室开展熏蒸实验。实验设置4个O_(3)熏蒸浓度(NF:未过滤的环境空气;NF40:环境空气+40 nmol/mol;NF80:环境空气+80 nmol/mol;NF120:环境空气+120 nmol/mol),每个处理设置3个重复组,分析评价O_(3)污染对植物造成的可见伤害、生产量、叶片解剖学特征以及食用部位营养指标的影响。研究表明:(1)O_(3)熏蒸对生菜叶片产生不可逆的可见伤害,叶片出现浅黄色斑点和棕色斑点,且随着熏蒸时间延长,叶片出现黄化,大面积的坏死斑块,衰老加速。(2)高浓度O_(3)胁迫显著降低了生长阶段的株高(P<0.05)。与NF组相比,NF40、NF80、NF120组分别使生物量下降5.90%、14.99%、39.21%。(3)随着O_(3)熏蒸浓度升高,气孔密度增加,气孔开度减小。叶片厚度、海绵组织厚度、栅栏组织厚度与O_(3)暴露剂量AOT40呈显著负相关关系(P<0.05)。(4)高浓度O_(3)暴露使蔬菜中Ca、Na、Fe、Zn、Mg等元素含量显著降低,脂肪和蛋白质含量增加,生菜的营养指标发生改变。研究表明,罗马直立生菜对环境O_(3)污染敏感,其生长发育及营养指标在O_(3)胁迫条件下发生明显变化。目前,关于O_(3)污染对蔬菜形态学特征影响的研究较少,研究系统探讨蔬菜的叶片厚度、栅栏组织、海绵组织、气孔密度及开度等形态学指标在臭氧污染条件下的变化。蔬菜的品质是关系到“三农”问题的重要方面,研究探讨了臭氧污染对蔬菜的产量及营养指标的影响,可为O_(3)污染条件下蔬菜的生产提供科学参考。

关键词：臭氧罗马直立生菜可见伤害叶解剖结构营养指标

On the molecular mechanism of ion specific Hofmeister series

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中国科学：化学英文版 2014年第1期57卷 36-47页

作者： XIE WenJun LIU ChengWen YANG LiJiang gao yiqin Peking National Laboratory for Molecular Sciences Institute of Theoretical and Computational Chemistry College of Chemistry and Molecular Engineering Peking University

Hofmeister series ranks the ability of salt ions in influencing a variety of properties and processes in aqueous *** this review,we reexamine how these ions and some other small molecules affect water structure and thermodynamic properties,such as surface tension and protein backbone *** illustrate the difficulties in interpreting the thermodynamic information based on structural and dynamic *** an alternative,we show that the solvation properties of ions and proteins/small molecules can be used to explain the salt effects on the thermodynamic properties of the *** analysis shows that the often neglected cation-anion cooperativity plays a very important role in these *** also argue that the change of hydrogen donor/acceptor equilibrium by added cosolutes/cosolvents can be used to explain their effects on protein secondary structure denaturation/protection:those increase hydrogen donor concentrations such as urea and salts with strongly solvated cations/weakly hydrated anions tend to dissolve protein backbone acting as secondary structure denaturants,whereas those lack of hydrogen donors but rich in acceptors have the opposite effect.

关键词： Hofmeister series,salt effects,ion cooperativity,hydrogen donor acceptor equilibrium,surface tension,protein dena-turant,protein protectant

Status and developmental trends in recombinant collagen preparation technology

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Regenerative Biomaterials 2024年第2期3卷 17-36页

作者： Xiaolei Guo Yuan Ma Hang Wang Hongping Yin Xinli Shi yiqin Chen Guobiao gao Lei Sun Jiadao Wang Yunbing Wang Daidi Fan Center for Medical Device Evaluation National Medical Products AdministrationBeijing 100081China State Key Laboratory of Tribology Tsinghua UniversityBeijing 100084China school of Life Science and Technology China Pharmaceutical UniversityNanjing 210009China National Engineering Research Center for Biomaterials&College of Biomedical Engineering Sichuan UniversityChengdu 610064China Biotech.&Biomed.Research Institute Northwest UniversityXi'an 710127China

Recombinant collagen is a pivotal topic in foundational biological research and epitomizes the application of critical bioengineer-ing *** technological advancements have pro-found implications across diverse areas such as regenerative medicine,organ replacement,tissue engineering,cosmetics and ***,recombinant collagen and its preparation methodologies rooted in genetically engineered celis mark pivotal milestones in medical product *** article pro-vides a comprehensive overview of the current genetic engi-neering technologies and methods used in the production of recombinant collagen,as well as the conventional production process and gquality control detection methods for this ***,the discussion extends to foresee the strides in physical transfection and magnetic control sorting studies,envisioning an enhanced preparation of recombinant collagen-seeded cells to further fuel recombinant collagen production.

关键词： recombinant collagen preparation genetic engineering collagen characterization physical transfection seed cell sorting

Nutritional and lipid profile status of children with spinal muscular atrophy in China:A retrospective case-control study

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Chinese Medical Journal 2024年第10期137卷 1243-1245页

作者： Yijie Feng Jia Wei Mei Yao Jianing Jin yiqin Cui Qi Long Fei Chen Yi Hong Dongming Zhou Jingjing Hu Xiao Chen Feng gao Changzheng Yuan Shanshan Mao Department of Neurology Children’s HospitalZhejiang University School of MedicineNational Clinical Research Center for Child HealthHangzhouZhejiang 310052China Department of Infection Children’s HospitalZhejiang University School of MedicineNational Clinical Research Center for Child HealthHangzhouZhejiang 310052China Department of Nutrition Children’s HospitalZhejiang University School of MedicineNational Clinical Research Center for Child HealthHangzhouZhejiang 310052China Children’s Hospital Zhejiang University School of MedicineNational Clinical Research Center for Child HealthHangzhouZhejiang 310052China School of Public Health Zhejiang University School of MedicineHangzhouZhejiang 310012China Children’s Hospital School of Public HealthZhejiang University School of MedicineNational Clinical Research Center for Child HealthHangzhouZhejiang 310052China

To the Editor:5q spinal muscular atrophy(5qSMA)is an autosomal recessive neuromuscular disorder caused by the lack of the survival motor neuron(SMN)protein encoded by the SMN1 gene,located at 5q11.2-q13.3.[1]The incidence is 1/10,000-1/6000 live births,and the mutation carrier rate in China is 1/42.[1]Spinal muscular atrophy(SMA)is mainly divided into four subtypes:SMA type I,II,III,and IV,based on the motor milestones ever *** I-III occur in children,[1]which often result in progressive muscular atrophy and weakness as well as multi-system dysfunction,including nutritional and metabolic issues.[2]Children with SMA may have hidden nutritional and lipid imbalances,despite normal body appearance and anthropometric measurements,making it difcult to detect early and intervene.

关键词： atrophy muscular children

跨文化语境下中西“逸品”研究的互鉴及其意义

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学术研究 2024年第7期 73-78页

作者：孙壹琴高小康中山大学哲学系广东广州510275 汕头大学文学院广东汕头515063

作为中国绘画品评体系中的最高品第,“逸品”通常指简约率真、自然不拘、高绝超俗的艺术品质、创作风格与品评标准。身处不同文化环境下的国内外学者通过美学、艺术理论与艺术史的研究角度对中国绘画领域内“逸品”概念的理论渊源、价... 详细信息

作为中国绘画品评体系中的最高品第,“逸品”通常指简约率真、自然不拘、高绝超俗的艺术品质、创作风格与品评标准。身处不同文化环境下的国内外学者通过美学、艺术理论与艺术史的研究角度对中国绘画领域内“逸品”概念的理论渊源、价值取向与创作实践层面进行了深入的探究。国内学者注重“逸品”概念界定与演变历程,并强调“逸品”概念从心的精神特征。国外学者趋向于从艺术风格的层面阐释“逸品”,并由此逐步将“逸品”概念引入中国古代绘画发展史以及日本艺术史之中,由于国内外研究对“逸品”概念从心与运笔特征的侧重不同,对双方成果进行互鉴研究有助于从理论与创作层面进一步丰富对“逸品”概念的阐释;也有助于拓展有关“逸品”概念实践范围的认知,促进“逸品”概念在世界文化语境下的形象化与可阐释性。

关键词：逸品思维认知绘画风格跨文化交流

Effect of octreotide on human pancreatic cancer cells after transfected with somatostatin receptor type 2 gene

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World Journal of Gastroenterology 2004年第15期10卷 2292-2294页

作者： Zheng-RenLiu Ren-yiqin gao-SongWu QingChang Da-YuWang Sheng-QuanZou Fa-ZuQiu DepartmentofGeneralSurgery TongjiHospitalTongjiMedicalCollegeHuazhongUniversityofScienceandTechnologyWuhan430030HubeiProvinceChina

AIM: To observe the effect of octreotide on apoptosis rate of human pancreatic cancer cells PC-3 after transfected with somatostatin receptor type 2 (SST2) ***: SST2 plasmid was transfected into PC-3 cells by liposome. Result of transfection was detected by immunocytochemical staining and Western *** rates of PC-3 cells under different dosages of octreotide were measured by MTT assay and flow cytometry (FCM).RESULTS: Apoptosis rate caused by octreotide of transfected PC-3 cells was 7.56+2.06% at the dosage of 0.20 μg/mL, 9.25+1.73% at the dosage of 0.40 μg/mL and 14.28±2.72% at the dosage of 0.80 μg/mL. Apoptosis rate caused by octreotide of non-transfected PC-3 cells was 5.76+0.75% at the dosage of 0.20 μg/mL, 6.69±0.80% at the dosage of 0.d0 μg/mL and 7.26±1.28% at the dosage of 0.80 μg/mL. Transfected PC-3 cells growth inhibition rate caused by octreotide was 9.36+1.34% at the dosage of 0.20 μg/mL, 12.03+1.44% at the dosage of 0.40 μg/mL and 20.23+4.21% at the dosage of 0.80 μg/mL. Non-transfected PC-3 cells growth inhibition rate caused by octreotide was 6.44+0.66% at the dosage of 0.20 μg/mL,7.65+0.88% at the dosage of 0.40 μg/mL and 9.29+1.32% at the dosage of 0.80 μg/mL. We found that octreotidecaused higher apoptosis rate and inhibition rate in transfected groups than in non-transfected groups (P<0.05)at the tested dosages (0.20, 0.40 and 0.80 μg/mL).CONCLUSION: Deficiency of SST2 was probably the major reason why octreotide had little effect on PC-3 *** SST2 gene could strengthen the ability of octreotide of killing PC-3 cells. It provided an experimental evidence for using both octreotide and transfection with SST2 gene on clinical treatment of pancreatic cancer.

关键词：奥曲肽胰腺癌肿瘤细胞基因转染生长激素抑制素受体2 质粒

Microscopic Insight into the Protein Denaturation Action of Urea and Its Methyl Derivatives

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Microscopic Insight into the Protein Denaturation Action of ...

Probing Spontaneous Base Flipping of A Single-Mismatched Base Pair in Double-Stranded DNA

中国化学会第五届全国生物物理化学会议（NCBPC5）

作者：丁蓓 Lijiang Yang Debopreeti Mukherjee Jianxin Chen yiqin gao Feng Gai Center for Ultrafast Science and Technology School of Chemistry and Chemical EngineeringShanghai Jiao Tong University College of Chemistry and Molecular Engineering Peking University Department of Chemistry and The Ultrafast Optical Processes Laboratory University of Pennsylvania

We employ site-specific two-dimensional infrared spectroscopy as well as molecular dynamics simulations to investigate the binding interactions of urea and three of its derivatives,methylurea,1,3-dimethylurea and tetramethylurea,with protein aromatic and polar *** find that（1） urea methylation leads to preferential interactions between the co-solvent molecules and aromatic sidechains with an affinity that increases with the number of methyl groups;（2） interactions with tetramethylurea cause significant dehydration of aromatic sidechains and the effect is most pronounced for tryptophan;and（3） while neither urea nor tetramethylurea shows preferential accumulation around a polar sidechain,the number of hydrogen-bond donors around this sidechain is significantly decreased in the presence of *** together,our findings suggest that these urea derivatives,especially tetramethylurea,can effectively disrupt hydrophobic interactions in ***,tetramethylurea can promote intramolecular hydrogen-bond formation and hence induce-helix folding in peptides,as observed.

关键词： cosolvent effect two-dimensional infrared spectroscopy vibrational probes

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Probing Spontaneous Base Flipping of A Single-Mismatched Bas...

Tautomerization-dependent Recognition and Excision of Oxidation Damage in Base-excision DNA Repair

第八届全国化学生物学学术会议

作者： Yandong Yin Lijiang Yang Guanqun Zheng Chan Gu Chengqi Yi Chuan He yiqin gao Xin-Sheng Zhao Beijing National Laboratory for Molecular Sciences Peking University State Key Laboratory for Structural Chemistry of Unstable and Stable Species Peking University Biodynamic Optical Imaging Center Peking University Department of Chemical Biology Peking University Institute of Theoretical and Computational Chemistry College of Chemistry and Molecular EngineeringPeking University Department of Chemistry the University of Chicago Biodynamic Optical Imaging Center Peking University Synthetic and Functional Biomolecules Center Peking University Beijing National Laboratory for Molecular Sciences Institute of Theoretical and Computational Chemistry College of Chemistry and Molecular Engineering Beijing National Laboratory for Molecular SciencesPeking University

＜正＞Many DNA base repairs and modifications,such as DNA methylation/demethylation, deamination,and hydroxylation,are known to occur extrahelically with the target base flipped out of the DNA *** these bases flip out of the DNA duplex, however,is still unknown（Figure A）.In this work,we probed,by applying the newly developed diffusion-decelerated fluorescence correlation spectroscopy（ddFCS）,the

关键词： Dynamics Spontaneous single base flipping ddFCS

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Tautomerization-dependent Recognition and Excision of Oxidat...