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On analytic formulas of Feynman propagators in position space

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Chinese Physics C 2010年第10期34卷 1576-1582页

作者： zhang Hong-Hao FENG Kai-Xi qiu Si-Wei ZHAO An LI Xue-Song School of Physics and Engineering Sun Yat-Sen University Science College Hunan Agricultural University

We correct an inaccurate result of previous work on the Feynman propagator in position space of a free Dirac field in （3 ＋ 1）-dimensional spacetime; we derive the generalized analytic formulas of both the scalar Feynman propagator and the spinor Feynman propagator in position space in arbitrary （D ＋ 1）- dimensional spacetime; and we further find a recurrence relation among the spinor Feynman propagator in （D＋1）-dimensional spacetime and the scalar Feynman propagators in （D＋1）-, （D-1）- and （D＋3）-dimensional spacetimes.

关键词： Feynman propagator Klein-Gordon field Dirac field arbitrary dimensional spacetime

Manganese enhances the expression of the manganese superoxide dismutase in cultured primary chick embryonic myocardial cells

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Journal of Integrative Agriculture 2017年第9期16卷 2038-2046页

作者： QIN Shi-zhen LIAO Xiu-dong LU Lin zhang Li-yang XI Lin GUO Yan-li LUO Xu-gang Mineral Nutrition Research Division Institute of Animal SciencesChinese Academy of Agricultural Sciences College of Animal Science and Technology Gansu Agricultural University Department of Animal Science North Carolina State University

In the present study, the effect of manganese（Mn） on antioxidant status and the expression of the manganese superoxide dismutase（MnSOD） gene in cultured primary myocardial cells collected from the chick embryos was investigated. The hypothesis that Mn supplementation would enhance the expression of MnSOD in cultured primary myocardial cells of chick embryos was tested. Eggs collected from Mn-depleted Arbor Acres laying breeder hens were incubated for 10 days and then myocardial cells were isolated and cultivated for 8 days. The embryonic myocardial cells on day 6 were treated with Mn in the cell culture medium at different time points when the proportion of cells showing spontaneous contraction was over 95% after the 3-day primary culture. A completely randomized design involving a 3 Mn levels（0, 0.5 and 1.0 mmol L^（-1））×3 incubation time points（12, 24 and 48 h） factorial arrangement of treatments（n=6） was used in the current experiment. The results showed that MnSOD activity and m RNA expression level were induced by Mn and increased with incubation time, which supported the hypothesis that Mn would enhance the expression of the MnSOD gene, and thus might protect myocardial cells from oxidative stress during the chick embryonic development.

关键词： manganese MnSOD expressions cultured primary myocardial cells chick embryos

RNA interference-mediated silencing of vATPase subunits A and E affect survival and development of the 28-spotted ladybeetle,Henosepilachna vigintioctopunctata

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Insect Science 2021年第6期28卷 1664-1676页

作者： Wei Guo Mujuan Guo Chunxiao Yang Zhuoqi Liu Shimin Chen Jing Lu Baoli qiu Youjun zhang Xuguo Zhou Huipeng Pan Key Laboratory of Bio-Pesticide Innovation and Application of Guangdong Province South China Agricultural UniversityGuangzhou510642China State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources South China Agrcultural Univer-sityGuangzhou510642China Department of Plant Protection Institute of Vegetables and FlowersChinese Academy of Agricultural SciencesBeijing100081China Department of Entomology University of KentuckyLexingtonKY40546USA

RNA interference(RNAi)has emerged as a powerful tool for developing novel management strategies for controlling insect *** 28-spotted ladybeetle,Henosepilachna vigintioctopunctata is one of the most important pests attacking solanaceous plants in *** this study,the potential of dietary RNAi to manage *** was investigated using both in vitro synthesized and bacterially expressed double-stranded RNAs(dsRNAs)of HvvATPase A and HvvATPase *** expression levels of HvvATPase A and HvvATPase E were higher in Malpighian tubules than in other tissue *** silencing of HvvATPase A and HvvATPase E led to significant mortality in *** *** addition,the ingestion of HvvATPase A and HvvATPase E significantly deterred feeding behavior and subsequently arrested the development of ***,the bacterially expressed dsRNAs consistently caused higher mortality in larvae and ***,the nontarget effects of the dsRNAs of *** on the predatory ladybeetle Propylaea japonica were *** 1st instar larvae were administered vATPase A and vATPase E dsRNAs from *** and *** under the worst-case scenario,in which dsGFP served as negative *** were significant effects of dsHvvATPase A on *** at the transcriptional level but not at the organismal level,whereas dsHvvATPase E did not effect *** at either the transcriptional or the organismal ***,the results of the study suggest that HvvATPase A and HvvATPase E can act as novel molecular targets for the control of ***.

关键词： dietary RNAi Henosepilachna vigintioctopunctata mortality nontarget effects Propylaea japonica vATPase

Predictors of outcomes of endoscopic balloon dilatation in strictures after esophageal atresia repair: A retrospective study

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World Journal of Gastroenterology 2020年第10期26卷 1080-1087页

作者： Dong-Ling Dai Chen-Xi zhang Yi-Gui Zou Qing-Hua Yang Yu Zou Fei-qiu Wen Department of Gastroenterology Shenzhen Children’s Hospital

BACKGROUND Endoscopic balloon dilatation (EBD) has become the first line of therapy for benign esophageal strictures (ESs);however,there are few publications about the predictive factors for the outcomes of this *** To assess the predictive factors for the outcomes of EBD treatment for strictures after esophageal atresia (EA) *** Children with anastomotic ES after thoracoscopic esophageal atresia repair treated by EBD from January 2012 to December 2016 were *** procedures were performed under tracheal intubation and intravenous anesthesia using a three-grade controlled radial expansion balloon with *** were recorded and predictors of the outcomes were *** A total of 64 patients were included in this *** rates of response,complications,and recurrence were 96.77%,8.06%,and 2.33%,*** number of dilatation sessions and complications were significantly higher in patients with a smaller stricture diameter (P=0.013 and 0.023,respectively) and with more than one stricture (P=0.014 and 0.004,respectively).The length of the stricture was significantly associated with complications of EBD (P=0.001).A longer interval between surgery and the first dilatation was related to more sessions and a poorer response (P=0.017 and 0.024,respectively).CONCLUSION The diameter,length,and number of strictures are the most important predictive factors for the clinical outcomes of endoscopic balloon dilatation in pediatric *** interval between surgery and the first EBD is another factor affectingresponse and the number of sessions of dilatation.

关键词： Children Endoscopic balloon dilatation Esophageal stricture Outcome Predictor

Targeting integrin pathways:mechanisms and advances in therapy

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Signal Transduction and Targeted Therapy 2023年第2期8卷 381-422页

作者： Xiaocong Pang Xu He Zhiwei qiu Hanxu zhang Ran Xie Zhiyan Liu Yanlun Gu Nan Zhao Qian Xiang Yimin Cui Department of Pharmacy Peking University First HospitalXishiku StreetXicheng District100034BeijingChina Institute of Clinical Pharmacology Peking University First HospitalXueyuan Road 38Haidian District100191BeijingChina

Integrins are considered the main cell-adhesion transmembrane receptors that play multifaceted roles as extracellular matrix(ECM)-cytoskeletal linkers and transducers in biochemical and mechanical signals between cells and their environment in a wide range of states in health and *** functions are dependable on a delicate balance between active and inactive status via multiple mechanisms,including protein-protein interactions,conformational changes,and *** to their exposure on the cell surface and sensitivity to the molecular blockade,integrins have been investigated as pharmacological targets for nearly 40 years,but given the complexity of integrins and sometimes opposite characteristics,targeting integrin therapeutics has been a *** date,only seven drugs targeting integrins have been successfully marketed,including abciximab,eptifibatide,tirofiban,natalizumab,vedolizumab,lifitegrast,and ***,there are approximately 90 kinds of integrin-based therapeutic drugs or imaging agents in clinical studies,including small molecules,antibodies,synthetic mimic peptides,antibody-drug conjugates(ADCs),chimeric antigen receptor(CAR)T-cell therapy,imaging agents,etc.A serious lesson from past integrin drug discovery and research efforts is that successes rely on both a deep understanding of integrin-regulatory mechanisms and unmet clinical ***,we provide a systematic and complete review of all integrin family members and integrin-mediated downstream signal transduction to highlight ongoing efforts to develop new therapies/diagnoses from bench to *** addition,we further discuss the trend of drug development,how to improve the success rate of clinical trials targeting integrin therapies,and the key points for clinical research,basic research,and translational research.

关键词： drugs mechanisms inactive

Purification, structure characterization and antioxidant activity of polysaccharides from Saposhnikovia divaricata

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Chinese Journal of Natural Medicines 2019年第10期17卷 792-800页

作者： MENG Yao YI Lin CHEN Lei HAO Jie LI Du-Xin XUE Jie XU Nai-Yu zhang zhen-Qing College of Pharmaceutical Sciences Soochow UniversitySuzhou 215123China Jiangsu Key Laboratory of Translational Research and Therapy for Neuro-Psycho-Diseases Soochow UniversitySuzhou 215021China

Polysaccharide from traditional Chinese herb, Saposhnikovia divaricata(Turcz.) Schischk.(SD) was extracted, fractionated and characterized in this work. Four fractions were prepared. Their molecular weight, monosaccharide compositions, linkage modes and structural properties were characterized with SEC-MALS-RI, HPAEC-PAD, GC-MS and NMR. SDP1 was assigned as a 1, 4-α-glucan with small amount of O-6 linked branches. SDP2 contained a big amount of the 1, 4-α-glucan and a small amount of arabinogalactan, while SDP3 possessed relatively lower amount of the 1, 4-α-glucan and a big amount of the arabinogalactan. SDP4 was defined as a pectic arabinogalactan. Four fractions showed antioxidant activities in both molecular and cellular levels and their activity was ranked as SDP4 ≈ SDP3>SDP2>SDP1. The 1, 4-α-glucan in SDP1 had the weakest, while SDP3 and SDP4 showed similar and the highest antioxidant activity. The arabinogalactan was the major component of both SDP3 and SDP4, which significantly contributed to the antioxidant activity of SDP.

关键词： Saposhnikovia divaricata Polysaccharides Arabinogalactan Antioxidant activity

Outcomes after primary coronary intervention with drugeluting stent implantation in diabetic patients with acute ST elevation myocardial infarction

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Chinese Medical Journal 2007年第21期120卷 1862-1867页

作者： zhang Qi SHEN Jie zhang Rui-yan qiu Jian-ping LU Ji-de zhang Yu CHEN Yue-hua zhang Jun-feng zhang Jian-sheng HU Jian YANG zhen-kun zhenG Ai-fang zhang Xian SHEN Wei-feng Department of Cardiology Ruijin Hospital Shanghai Jiao Tong University School of Medicine Shanghai 200025 China Department of Cardiology Shanghai Gongli Hospital Shanghai 200025 China Department of Cardiology Third People＇s Hospital Shanghai Jiao Tong University School of Medicine Shanghai 200025 China

Background Drug-eluting stent （DES） has been used widely for the treatment of patients with acute coronary syndrome with or without diabetes mellitus during percutaneous coronary intervention （PCI）, but its long-term safety and efficacy in diabetic patients with acute ST elevation myocardial infarction （STEMI） remain uncertain. This study aimed to investigate the clinical outcomes after primary coronary intervention with DES implantation for diabetic patients with acute STEMI, compared with non-diabetic counterparts. Methods From December 2004 to March 2006, 56 consecutive diabetic patients （diabetic group） and 170 non-diabetic patients （non-diabetic group） with acute STEMI who underwent primary PCI with DES implantation in 3 hospitals were enrolled. Baseline clinical, angiographic, and procedural characteristics, as well as occurrence of major adverse cardiac event （MACE） including cardiac death, non-fatal recurrent myocardial infarction （re-MI） and target vessel revascularization （TVR） during hospitalization and one-year clinical follow-up were compared between the two groups. Results Patients in diabetic group were more hyperlipidemic （69.6% and 51.8%, P=-0.03） and had longer time delay from symptom onset to admission （（364±219） minutes and （309±223） minutes, P=-0.02） than those in non-diabetic group. The culprit vessel distribution, reference vessel diameter, and baseline TIMI flow grade were similar between the two groups, but multi-vessel disease was more common in diabetic than in non-diabetic group （82.1% and 51.2%, P〈0.001）. Despite similar TIMI flow grades between the two groups after stenting, the occurrence of TIMI myocardial perfusion grade （TMPG）〉2 was lower in diabetic group （75.0% vs 88.8% in non-diabetic groups, P=-0.02）. The MACE rate was similar during hospitalization between the two groups （5.4% vs 3.5%, P=-0.72）, but it was significantly higher in diabetic group （16.1%） during one-year follow-up, as compared with non-diabetic group （6.5%, P=-0.

关键词： acute myocardial infarction drug-eluting stent clinical outcome primary coronary intervention

Anti-corrosive Hybrid Electrolytes for Rechargeable Aqueous Zinc Batteries

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Chemical Research in Chinese Universities 2021年第2期37卷 328-334页

作者： WANG Jia qiu Huayu ZHAO Zhiming zhang Yuchen ZHAO Jingwen MA Yinglei LI Jiedong XING Min LI Guicun CUI Guanglei College of Materials Science and Engineering Qingdao University of Science and TechnologyQingdao266042P.R.China Qingdao Industrial Energy Storage Research Institute Qingdao Institute of Bioenergy and Bioprocess TechnologyChinese Academy of SciencesQingdao266101P.R.China

Aqueous zinc(Zn)-metal cells with cost-effective components and high safety have long been a promising large-scale energy storage system,but Zn anodes are intrinsically unstable with common aqueous electrolytes,causing substantial underutilization of the theoretical *** this work,we report a strictly neutral aqueous Zn electrolyte at a low cost by leveraging the dynamic hydrolysis equilibrium of a dual-salt Zn(Ac)2/NaAc(Ac:CH3COO−)*** the pH regulation,the corrosion and hydrogen evolution encountered in Zn anodes can be suppressed *** hybrid aqueous electrolyte not only enables dendrite-free Zn plating/stripping at a nearly 95%Coulombic efficiency[an increase of 24%compared to that of the single-salt 1 mol/L Zn(Ac)2 electrolyte],but also supports the reversible operation of Zn cells paired with either Na3V2(PO4)3 or iodine cathodes—the former delivers a high output voltage of 1.55 V with an energy level of 99.5 W·h/kg(based on the mass of the cathode),and the latter possesses a high specific capacity of 110.9 mA·h/g while yielding long-term cyclability(thousands of cycles).These findings open up a new avenue of modifying practical electrolytes having targeted properties to stabilize multivalent metal anodes.

关键词： pH regulation Aqueous Zn-based battery Na3V2(PO4)3 cathode

Extraction and back-extraction behaviors of 14 rare earth elements from sulfuric acid medium by TODGA

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Journal of Rare Earths 2018年第6期36卷 642-647页

作者： Huiting Yuan Weixiang Hong Yushan Zhou Baisong Pu Aijun Gong Tao Xu Qishan Yang Fukai Li Lina qiu Weiwei zhang Yuning Liu School of Chemistry and Biological Engineering University of Science and Technology BeijingBeijing 100083China North China Rare Earth Hi-Tech Company Limited Baotou 014030China School of Chemistry and Chemical Engineering Inner Mangolia University of Science and TechnologyBaotou 014010China

The unique physical and chemical properties of rare earth elements lay the foundation for their extensive application. N,N,N’,N’ Tetra-octyl-3-oxopentanediamide(TODGA) is excellent in its ability of extracting rare earth elements and it is favored for green initiative. In this paper, the extraction and back-extraction of14 rare earth elements by TODGA were studied. Experiments show that in conditions of 6 mol/L sulfuric acid, the extraction temperature of 25 ℃,the phase ratio of 1:1 and 0.04 mol/LTODGA(aviation kerosene as the diluent), the extraction rates of 14 rare earth elements including lanthanum, cerium, praseodymium,neodymium, europium, gadolinium, terbium, dysprosium, holmium, erbium, thulium, ytterbium, lutetium, and yttrium were 99.00%-99.73%. Mixed with hydrochloric acid and nitric acid(HCl 3.5 mol/L, HNO30.5 mol/L), the recoveries of the 14 rare earth elements are 91.52%-99.91% when the extraction temperature is 25 ℃ and the ratio is 1:1. The following application is based on the optimum conditions above with practical samples(from the roasting production line of China North Rare Earth High-tech Company Limited) for extraction and back-extraction experiments. Experiments show that TODGA has excellent enrichment effect on 14 rare earth elements, the extraction rates are 91.36%-99.80%, the back-extraction rates are 87.29%-99.64% and the total recoveries are 81.19%-99.44%.

关键词： Rare earth Extraction Back-extraction N,N,N',N' Tetra-octyl-3-oxopentanediamide(TODGA) Enrichment