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Photosynthesis and biochemical responses to elevated O_3 in Plantago major and Sonchus oleraceus growing in a lowland habitat of northern China

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Journal of Environmental Sciences 2017年第3期29卷 113-121页

作者： Benying su Meihua Zhou hong Xu Xiujie Zhang Yonggeng Li Hua su Bao Xiang State Key Laboratory of Environmental Criteria and Risk Assessment Chinese Research Academy of Environmental Sciences State Key Laboratory of Vegetation and Environmental Change Institute of BotanyChinese Academy of Sciences

A field experiment was carried out to compare the responses to ozone （03） in two common herbaceous plant species, Plantago major L. and Sonchus oleraceus L., by building open-top growth chambers in situ to simulate 03 stress （＋03, 85 ± 5 ppb, 9 hr/day for 30 days） in a lowland habitat in Inner Mongolia, Northern China. Responses to 03 of gas exchange, chlorophyll a fluorescence, leaf pigment content, andoxidant capability, soluble protein content, membrane lipid peroxidation and dark respiration （Rd） were analyzed. Results showed that elevated 03 exposure significantly reduced the light-saturated net photosyn- thesis （PNsat）, stomata] conductance （gs） and transpiration rate （E） in both species. Although non-significant interactive effect between species and 0s on PNsat was analyzed, the reduction in PNsat in S. oleraceus might be due primarily to the higher fraction of close PSII reaction centers and impaired activities of plant mesophyll cells as evidences by decreased maximum efficiency of PSII photochemistry after dark adapted state （Fv/Fm） and unchanged intercellular CO2 concentration （Ci）. Besides, biochemical analysis showed that S. oleraceus had lower antioxidant ability compared to P. major. As a result, S. oleraceus was damaged to the larger extent in terms of lipid peroxidation and visible O3 injury, indicating that S. oleraceus was more sensitive to O3 than P. major. Our results indicated that wild herbaceous plant species growing in a lowland habitat in sandy grassland were sensitive to O3 stress and S. oleraceus can be considered as one of the bio-indicators for high O3 concentration in semi-arid -rassland of northern China.

关键词： Biochemical analysisHerbaceous speciesGas exchangeOzoneSemi-arid grassland

Maintaining moderate levels of hypochlorous acid promotes neural stem cell proliferation and differentiation in the recovery phase of stroke

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Neural Regeneration Research 2025年第3期20卷 845-857页

作者： Lin-Yan Huang Yi-De Zhang Jie Chen Hai-Di Fan Wan Wang Bin Wang Ju-Yun Ma Peng-Peng Li Hai-Wei Pu Xin-Yian Guo Jian-Gang Shen su-Hua Qi School of Medical Technology Xuzhou Key Laboratory of Laboratory DiagnosticsXuzhou Medical UniversityXuzhouJiangsu ProvinceChina School of Pharmacy Xuzhou Medical UniversityXuzhouJiangsu ProvinceChina Department of Laboratory Medicine Branch Hospital of Huai’an First People’s HospitalHuai’anJiangsu ProvinceChina Department of Laboratory Medicine the Affiliated Hospital of Xuzhou Medical UniversityXuzhouJiangsu ProvinceChina School of Chinese Medicine The University of Hong KongHong Kong Special Administrative RegionChina

It has been shown clinically that continuous removal of ischemia/reperfusion-induced reactive oxygen species is not conducive to the recovery of late ***,previous studies have shown that excessive increases in hypochlorous acid after stroke can cause severe damage to brain *** previous studies have found that a small amount of hypochlorous acid still exists in the later stage of stroke,but its specific role and mechanism are currently *** simulate stroke in vivo,a middle cerebral artery occlusion rat model was established,with an oxygen-glucose deprivation/reoxygenation model established in vitro to mimic *** found that in the early stage(within 24 hours)of ischemic stroke,neutrophils produced a large amount of hypochlorous acid,while in the recovery phase(10 days after stroke),microglia were activated and produced a small amount of hypochlorous ***,in acute stroke in rats,hypochlorous acid production was prevented using a hypochlorous acid scavenger,taurine,or myeloperoxidase inhibitor,4-aminobenzoic acid *** results showed that high levels of hypochlorous acid(200μM)induced neuronal apoptosis after oxygen/glucose deprivation/***,in the recovery phase of the middle cerebral artery occlusion model,a moderate level of hypochlorous acid promoted the proliferation and differentiation of neural stem cells into neurons and *** suggests that hypochlorous acid plays different roles at different phases of cerebral ischemia/reperfusion *** levels of hypochlorous acid(5 and 100μM)promoted nuclear translocation ofβ-*** transfection of single-site mutation plasmids,we found that hypochlorous acid induced chlorination of theβ-catenin tyrosine 30 residue,which promoted nuclear ***,our study indicates that maintaining low levels of hypochlorous acid plays a key role in the recovery of neurological function.

关键词： cell differentiation cerebral ischemia/reperfusion injury chlorination hypochlorous acid microglia neural stem cell neurogenesis nuclear translocation stroke β-catenin

Effect of cyclic wetting-drying on tensile mechanical behavior and microstructure of clay-bearing sandstone

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International Journal of Coal Science & Technology 2021年第5期8卷 956-968页

作者： Pingye Guo juan Gu Yi su Jiong Wang Zhanwen Ding State Key Laboratory for Geo-Mechanics and Deep Underground Engineering Beijing 100083China School of Mechanics Architecture and Civil EngineeringChina University of Mining and TechnologyBeijing 100083China Tang Steel International Engineering Technology Corp Tangshan 063000China China Henan Geological and Mineral Resources Construction Engineering(Group)Co. LtdZhengzhou 450007China

The understanding of the weakening mechanism of tensile strength of rock subjected to cyclic wetting-drying is critical for rock *** strength tests were conducted on a total of 35 sandstone specimens with different wetting-drying *** crack propagation process and acoustic emission characteristics of the tested samples were obtained through a high-speed camera and acoustic emission *** results indicate that the tensile strength is observably reduced after cyclic wetting-drying,and the extent of the reduction is not only related to the number of wettingdrying cycle,but also closely related to the clay mineral content of the *** addition,as the cycles of wetting-drying increase,the effect of each single cycle on tensile strength get reduced until it becomes ***,the crack initiation and penetration time is prolonged as the number of wetting-drying cycle increases,which indicates that cyclic wetting-drying weakens the rock stiffness and enhances the ductility of ***,the acoustic emission characteristics of the tested samples further confirmed the ductile behaviour of the sandstone samples with increasing wetting-drying ***,through the analysis of the microstructure and mineral composition of the samples with different wetting-drying cycles,it is concluded that the main weakening mechanisms of sandstones containing clay minerals are frictional reduction,chemical and corrosive deterioration.

关键词： Sandstone Wetting-drying cycle Tensile strength Weakening mechanism Failure characteristics

Amiodarone-induced hepatotoxicity-quantitative measurement of iodine density in the liver using dual-energy computed tomography:Three case reports

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World Journal of Clinical Cases 2020年第20期8卷 4958-4965页

作者： Hai-juan Lv hong-Wei Zhao Department of Radiology The Second Affiliated Hospital of Jiaxing UniversityJiaxing 314000Zhejiang ProvinceChina

BACKGROUND Amiodarone is the drug most commonly used to manage ***-term amiodarone administration causes hepatotoxicity due to iodine accumulation in the ***,we present three cases of amiodarone-induced hepatotoxicity in patients on long-term oral amiodarone therapy who underwent dual-energy computed tomography(DECT).CASE suMMARY We report the clinical and iodine density in the liver using DECT in three patients with amiodarone-induced *** enzymes were increased in these three patients,and abdominal DECT without contrast medium showed highly increased attenuation in the ***,the iodine concentration in the liver was *** first patient with amiodarone-induced reversible hepatotoxicity,showed a reversible course of liver function and a decrease in CT values after discontinuation of *** second patient on long-term oral amiodarone had increased iodine concentration in the liver and liver damage,the patient eventually developed rapidly progressive pneumonia and died of multiple organ *** third patient,showed an increased iodine concentration in the liver and elevated liver ***,the patient refused radiofrequency ablation for atrial fibrillation and continued oral amiodarone to control atrial fibrillation,and routine liver function tests were required every 3-6 mo in this *** DECT is a potentially noninvasive diagnostic tool for quantifying iodine concentration in the liver and monitoring adverse reactions due to amiodarone.

关键词： Case report Amiodarone Hepatotoxicity Iodine density Computed tomography Dual energy Arrhythmias

Barriers to colorectal cancer screening:A case-control study

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World Journal of Gastroenterology 2009年第20期15卷 2531-2536页

作者： Shan-Rong Cai su-Zhan Zhang hong-hong Zhu Shu Zheng Cancer Institute Zhejiang University 88 Jiefang Rd. Hangzhou 310009 Zhejiang Province China Division of Epidemiology Department of Community Health Saint Louis University School of Public Health 3545 Lafayette Ave. St Louis Missouri 63104 United States Department of Epidemiology Johns Hopkins University Bloomberg School of Public Health Baltimore Maryland 21205 United States

AIM:To investigate barriers to colorectal cancer(CRC) screening in a community ***:We conducted a community-based case-control study in an urban Chinese population by *** were selected from those completing both a fecal occult blood test(FOBT) case and colonoscopy in a CRC screening program in *** groups were matched by gender, age group and *** 1 included those having a positive FOBT but refusing a *** 2 included those who refused both an FOBT and ***:The impact of occupation on willingness to attend a colorectal screening program differed by gender.P for heterogeneity was 0.009 for case vs control group 1, 0.01 for case versus control group 2, and 0.80 for control group 1 vs *** awareness of CRC and its screening program, characteristics of screening tests, and lack of time affected the screening *** support, fear of pain and bowel preparation were barriers to a colonoscopy as a screening ***-two percent of control group 1 and 87.1% of control group 2 were willing attend if the colonoscopy was free, but only 56.3% and 53.1%, respectively, if it was *** odds ratios for case vs control group 1 were 0.10 among those unwilling to attend a free colonoscopy and 0.50 among those unwilling to attend a self-paid ***:Raising the public awareness of CRC and its screening, integrating CRC screening into the health care system, and using a painless colonoscopy would increase its screening rate.

关键词： Colorectal cancer screening Barrier Community-based case-control study Colonoscopy Fecal occult blood test

Protection of ghrelin postconditioning on hypoxia/ reoxygenation in gastric epithelial cells

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World Journal of Gastroenterology 2012年第38期18卷 5377-5388页

作者： Zhang-Bo Liu su-juan Fei Sheng-Ping Zhu Jin-Zhou Zhu hong-Xia Han Qiu-Ju Dong Jian-Fu Zhang DepartmentofGastroenterol-ogy TheAffiliatedHospitalofXuzhouMedicalCollege99WestHuaihaiRoadXuzhou221002JiangsuProvinceChina Department of Physiology Xuzhou MedicalCollege Xuzhou 221002 Jiangsu Province China

AIM: To investigate the protective effect and mechanisms of ghrelin postconditioning against hypoxia/reoxygenation (H/R)-induced injury in human gastric epithelial cells. METHODS: The model of H/R injury was established in gastric epithelial cell line (GES-1) human gastric epithelial cells. Cells were divided into seven groups: normal control group (N); H/R postconditioning group; DMSO postconditioning group (DM); ghrelin postconditioning group (GH); D-Lys3-GHRP-6 + ghrelin postconditioning group (D + GH); capsazepine + ghrelin postconditioning group (C + GH); and LY294002 + ghrelin postconditioning group (L + GH). 3-(4,5-dimethylthazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assay was used to detect GES-1 cell viability. Hoechst 33258 fluorochrome staining and flow cytometry were conducted to determine apoptosis of GES-1cells. Spectrophotometry was performed to determine release of lactate dehydrogenate (LDH). Protein expression of Bcl-2, Bax, Akt, and glycogen synthase kinase (GSK)-3β was determined by western blotting. Expression of vanilloid receptor subtype 1 (VR1), Akt and GSK-3β was observed by immunocytochemistry. REsuLTS: Compared with the H/R group, cell viability of the GH group was significantly increased in a dosedependent manner (55.9% ± 10.0% vs 69.6% ± 9.6%, 71.9% ± 17.4%, and 76.3% ± 13.3%). Compared with the H/R group, the percentage of apoptotic cells in the GH group significantly decreased (12.38% ± 1.51% vs 6.88% ± 0.87%). Compared with the GH group, the percentage of apoptotic cells in the D + GH group, C + GH group and L + GH groups significantly increased (11.70% ± 0.88%, 11.93% ± 0.96%, 10.20% ± 1.05% vs 6.88% ± 0.87%). There were no significant differences in the percentage of apoptotic cells between the H/R and DM groups (12.38% ± 1.51% vs 13.00% ± 1.13%). There was a significant decrease in LDH release following ghrelin postconditioning compared with the H/R group (561.58 ± 64.01 U/L vs 1062.45 ± 105.29 U/L). There was a significant

关键词： Protection of ghrelin postconditioning on hypoxia/ reoxygenation in gastric epithelial cells

Activation of CFTR-mediated Cl^- Transport by Capsaicinoids in Cell Culture Model

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Chemical Research in Chinese Universities 2009年第2期25卷 220-223页

作者： ZHAO Xue-hang HOU Tmg-ting GE hong suN juan-juan YANG hong MA Tong-hui Membrane Channel Research Laboratory Northeast Normal University Changchun 130024 P. R. China Liaoning Provincial Key Laboratory of Biotechnology and Drug Discovery School of Life Sciences Liaoning Normal University Dalian 116029 P. R. China

Previous studies reported that capsaicin potentiates AF508 mutant cystic fibrosis transmembrane conductance regulator（CFTR） channel gating defect by transfected cell-based assays. It has been postulated that orally ingested capsaicin may conceptually be used to develop a therapeutic strategy to treat gastrointestinal disorders in CF patients. We tried to reproduce and extend those pre-clinical data of previous studies. Cell-based fluorescence func- tional measurements in Fischer thyroid epithelial cells（FRT） expressing CFTR showed no effect of capsaicin on potentiating AF508-CFTR, while genistein showed a strongly positive activity. Studies show that capsaicin and dihy- drocapsaicin activated cAMP-prestimulated wild-type CFTR in a dose-dependent manner with a maximal response of 70% of that activated by genistein, thus gave an apparent EC50 of （40.4±6.8）μmol/L and （150.2±7.4） μtmol/L respectively. Preliminary study shows that the binding sites for capsaicin and dihydrocapsaicin may be probably partially overlapped with that for genistein because the maximal activation of wild-type CFTR with genistein is partially blocked by caosaicin and dihydrocapsaicin.

关键词： Capsaicinoid Cystic fibrosis transmembrane conductance regulator(CFTR) Activation

S/N Ratio of 4-Channel A/D Geological Radar Non-uniform Sampling Signals

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Journal of China University of Mining and Technology 2007年第4期17卷 534-536页

作者： MA Kai su hong-qi Computer StaffRoom Xuzhou Medical College Xuzhou Jiangsu 221002 China School of Mechanical Electronic and Information Engineering China University of Mining ＆ Technology Beijing 100083 China

Using the quantitative error probability density method we studied the S/N ratio of alternately sampled signals digitized by a 4-channel A/D. A complete expression for the S/N ratio of a 4-channel A/D non-uniform sampling signal was deduced. First we obtained an expression for the S/N ratio of a 1-channel A/D uniform sampling signal when the sampling frequency was equal to or greater than 2 times the frequency of the sampled signal. Based on the S/N ratio of a 2-channel A/D,alternating,non-uniform sampling signal,we analyzed the distribution of quantitative error using the quantitative error probability density method and the distribution convolution formula. From this the S/N ratio expression of a 4-channel A/D sampling signal was deduced. The simulation result shows that the deduced expression is correct.

关键词： geological radar 4-channel non-uniform sampling sum distribution S/N ratio

A density functional theory study on the interaction between UO_2^(2+) and the carbamoylphosphoramidic acid ligand for uranium extraction from seawater

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Nuclear Science and Techniques 2018年第6期29卷 128-140页

作者： Xiao-Jing Guo Cheng Li Jiang-Tao Hu hong-juan Ma hong-Liang Qian Shanghai Institute of Applied Physics Chinese Academy of Sciences School of Engineering China Pharmaceutical University

Phosphorylurea molecules, which contain both phosphoryl and carbonyl groups, are considered efficient extractants for UO_2^(2+). This study aims to explain the complexation of UO_2^(2+)with carbamoylphosphoramidic acid(CPO), a simple model for phosphorylurea, for ligand design for uranium recovery from seawater using density functional theory calculations, natural bond order analysis,and the quantum theory of atoms in molecules. The results showed that, when CPO acts as a monodentate ligand, the affinity of phosphoryl for UO_2^(2+)is stronger than that of carbonyl, and CPO coordinates with UO_2^(2+)through the phosphoryl oxygen atom. When CPO serves as a bidentate ligand, both the phosphoryl and carbonyl oxygen atoms connect to UO_2^(2+), and the U–O(carbonyl) bond plays a more important role than the U–O(phosphoryl) bond in the interaction between UO_2^(2+)and CPO. This paradox may be caused by the significant charge transfer from the U–O(carbonyl) p bond orbital to the C–N σ antibond orbital of the bidentate CPO. The NH spacer between the phosphoryl and carbonyl groups could ensure the delocalization of the electron system of the molecule. The bidentate binding motif is favored by entropy and opposed by enthalpy, while the monodentate binding motif is favored by enthalpy and opposed by entropy. Ultimately, the bidentate binding motif is more favorable than the monodentate one. As expected, the interaction between UO_2^(2+)and the deprotonated CPO is stronger than that between UO_2^(2+)and the neutral CPO. Comparing the interaction between UO_2^(2+)and CPO with that between UO_2^(2+)and Nphenylcarbamoylphosphoramidic acid(Ph CPO), formed by replacing one hydrogen atom from the terminal nitrogen atom of CPO with a phenyl group, the phenyl substituent at the terminal nitrogen atom of Ph CPO shows a slightly negative effect on the interaction between UO_2^(2+)and Ph CPO.

关键词：相互作用理论学习海水密度抽取 CPO 铀苯基取代