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Two New Triterpenes from Astilbe chinensis

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Chinese Chemical Letters 2006年第5期17卷 628-630页

作者： Jun yi hu Zhi YAO Jie TENG Yoshihisa TAKAISHI Hong Quan DUAN The College of Pharmaceuticals and Biotechnology Tianjin University Tianjin 300072 School of Chemical Engineering A.nshanUniversity of Science ＆ Technology Liaoning 114002 Department of Immunology Tianjin Medical University Tianjin300070 Faculty of Pharmaceutical Sciences University of Tokushima Shomachi 1-78 Tokushirna 770-8505 Japan School of Pharmacy Tianjin Medical University Tianjin 300070

Two new triterpenoids, 3β, 6β, 24-trihydroxyolean-12-en-27-oic acid and 3β-acetoxy-6β-hydroxyurs-12-en-27-oic acid, as well as three known triterpenoids were isolated from ~e rhizomes of Astilbe chinensis. Their s... 详细信息

关键词： Astilbe chinensis triterpene cytotoxic activities.

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Research on the On-orbit Background of the Hard X-Ray Imager Onboard ASO-S

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Research in Astronomy and Astrophysics 2022年第9期22卷 116-131页

作者： Wei Liu Deng-yi Chen Xian-Kai Jiang Jian Wu Zhe Zhang yi-Ming hu Yang Su Wei Chen Tao Ma Key Laboratory of Dark Matter and Space Astronomy Purple Mountain ObservatoryChinese Academy of SciencesNanjing 210023China School of Astronomy and Space Science University of Science and Technology of ChinaHefei 230026China

The space environment background of various particle fluxes of the Hard X-ray Imager(HXI), one of the payloads of the Advanced Space-based Solar Observatory(ASO-S) spacecraft, is investigated and presented. Different approaches are used to obtain the input information on various space environment particles(protons, alpha particles, electrons, positrons, neutrons, and photons). Some special regions(SAA and radiation belt) are also taken into account. The findings indicate that electrons are the primary background source in the radiation belt. Due to the large background flux generated by electrons, HXI cannot effectively observe solar flares in the radiation *** the radiation belt, primary protons and albedo photons are the main sources of background at low and high magnetic latitudes respectively. The statistical analysis of the flare and background spectra shows that the errors of the flare energy spectrum observation are mainly concentrated in the high energy band, and the detector still has a certain spectrum observation capability for flares of C-class and below in the low energy band of the non-radiation belt. The imaging observation of flares of C-class and below is significantly affected by the accuracy of background subtraction. The energy band with the best signal-to-noise ratio is from 10 to 50 ke V, which can be used to monitor the formation and class of flares.

关键词： instrumentation:detectors Sun:X-rays gamma-rays X-rays:diffuse background (cosmology:)cosmic background radiation

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A Study on the Biocompatibility of MgO Coating Prepared by Anodic Oxidation Method on Magnesium Metal

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Journal of Bionic Engineering 2020年第1期17卷 76-91页

作者： Yangmei Chen Xugang Lu Fenghua Zhao yi hu Shibing Xiong Yuqiang Guo Ping huang Bangcheng Yang Engineering Research Center in Biomaterials Sichuan UniversityChengdu 610064China National Engineering Research Center for Biomaterials Sichuan UniversityChengdu 610064China Sichuan Guojia Biomaterials Co. LtdChengdu 610064China Jiangsu Collaborative Innovation Center of Biomedical Functional Materials Nanjing Normal UniversityNanjing 210046China Panzhihua International Research Institute of Vanadium and Titanium Panzhihua UniversityPanzhihua 617000China

Magnesium(Mg),is widely used for the bone repair in oral and orthopedic application due to excellent bioactivity,degradation and ***,the range of application is greatly limited because of the rapid degradation of Mg metal in the *** modification is an effective method to enhance the corrosion resistance and reduce the degradation rate of Mg *** the present study,pure Mg metal(P-Mg)was subjected to alkali-heat treatment(AT-Mg)or anodic oxidation-heat treatment(AO-HT-Mg).Both AT-Mg and AO-HT-Mg had a layer of MgO on their surfaces after *** the effects of MgO coating on corrosion resistance,bioactivity,Mesenchymal Stem Cells’(MSCs)proliferation,adhesion and osteogenic differentiation,and the bone repair capability of Mg metal were *** found both AT-Mg and AO-HT-Mg had stronger corrosion resistance than *** on both AT-Mg and AO-HT-Mg had higher expression of proteins and genes of ALP,OCN,Col-I and Runx2 than those on *** also showed better bone repair property than P-Mg in *** general,MgO layer formed by anodic oxidation-heat treatment had better resistance and biocompatibility than that produced by alkali-heat *** study indicated the MgO coating not only improved the corrosion resistance of Mg metal,but also promoted the osteogenic differentiation of MSCs and bone regeneration.

关键词： magnesium MgO coating alkali-heat treatment anodic oxidation-heat treatment corrosion resistance biomedical-materials

220 GHz Multi Circuit Integrated Front End Based on Solid-State Circuits for High Speed Communication System

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Chinese Journal of Electronics 2022年第3期31卷 569-580页

作者： NIU Zhongqian ZHANG Bo DAI Bingli ZHANG Jicong SHEN Fang hu yi FAN Yong ZHANG yihan School of Electronic Science and Engineering University of Electronic Science and Technology of China Chongqing Institute of Microelectronics Industry Technology University of Electronic Science and Technology of China

This paper presents the research on a 220 GHz multi circuit inte-grated front end based on solidstate circuits. This integrated front end integrates a 220 GHz subharmonic mixer, a 110 GHz tripler, a 110 GHz 8 d B hybrid coupler and a 220 GHz waveguide bandpass filter(BPF) in one single block. Compared to the traditional transceivers which usually use cascade connection of the independent mixers and multipliers, the size of the proposed multi circuit integrated front-end block is 25 mm × 20 mm × 20 mm, ten times smaller than the cascading transceiver. In order to check the tripler’s output power, a modified compact 110 GHz 8 d B hybrid coupler is set between mixer and tripler. Due to the characteristics of the hybrid coupler, the deterioration of cascading transceiver’s performance caused by mismatch has also been improved. In addition, to achieve single sideband(SSB) communication, a 220 GHz BPF with high selectivity is integrated in the circuit. The measured conversion loss of the fabricated multi circuit integrated front end is less than 11 d B, where the LO and RF frequency are 37 and 210-220 GHz. Based on this front-end, a 220 GHz high speed communication system has been setup and it can achieve 10 Gbps data transmission using 16 QAM modulation.

关键词： BPF compact hybrid coupler traditional transceivers millimetre wave frequency convertors solid-state circuits frequency multipliers multipliers waveguide bandpass filter millimetre wave mixers cascading transceiver performance conversion loss multicircuit integrated front-end block millimetre wave couplers SSB communication subharmonic mixer 16QAM modulation high speed communication system independent mixers radio transceivers cascade connection band-pass filters single sideband communication

Synthesis of Vitamin E Succinate from Candida rugosa Lipase in Organic Medium

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Chemical Research in Chinese Universities 2013年第2期29卷 223-226页

作者： JIANG Xiang-jun hu yi JIANG Ling GONG Ji-hong huANG He School of Biotechnology and Pharmaceutical Engineering Nanjing University of Technology Nanjing 210009 P. R. China

A screening of commercially available lipases for the synthesis of vitamin E succinate showed that lipase from Candida rugosa presented the highest yield. The synthesis of vitamin E succinate in organic solvents with dif- ferent lgP values ranging from -1.3 to 3.5 was investigated. Of particular interest was that dimethyl sulfoxide （DMSO） with the lowest lgP exhibited the highest yield among all the organic solvents used. It suggests that lgP is incapable of satisfactorily predicting the biocompatibility of organic solvents due to the complexity of enzymatic reaction with hydrophilic and hydrophobic substrates in organic solvent. Effects of different operating conditions, such as molar ratio of substrate, enzyme concentration, reaction temperature, mass transfer, and reaction time were also studied. Under the optimum conditions of 10 g/L enzyme, a stirring rate of 100 r/min, a substrate molar ratio of 5：1 at 55℃ for 18 h, a satisfactory yield（46.95%） was obtained. The developed method has a potential to be used for efficient enzymatic production of vitamin E succinate.

关键词： Vitamin E succinate Candida rugosa lipase Operating condition

Innate and adaptive immune escape mechanisms of hepatitis B virus

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World Journal of Gastroenterology 2022年第9期28卷 881-896页

作者： hua-Jun Zhao yi-Fei hu Qiu-Ju Han Jian Zhang Institute of Immunopharmaceutical Sciences School of Pharmaceutical SciencesShandong UniversityJinan 250012Shandong ProvinceChina

Chronic hepatitis B virus(HBV)infection is an international health problem with extremely high mortality and morbidity *** current clinical chronic hepatitis B(CHB)treatment strategies can partly inhibit and eliminate HBV,viral breakthrough may result due to non-adherence to treatment,the emergence of viral resistance,and a long treatment *** CHB infection arises as a consequence of complex interactions between the virus and the host innate and adaptive immune ***,understanding the immune escape mechanisms involved in persistent HBV infection is important for designing novel CHB treatment strategies to clear HBV and achieve long-lasting immune *** review details the immunological and biological characteristics and escape mechanisms of HBV and the novel immune-based therapies that are currently used for treating HBV.

关键词： Hepatitis B virus Innate immunity Adaptive immunity Immune tolerance Therapeutic strategy

2D layered black arsenic-phosphorus materials:Synthesis,properties,and device applications

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Nano Research 2022年第4期15卷 3737-3752页

作者： Junchuan Liang yi hu Kaiqiang Zhang Yaoda Wang Xinmei Song Anyang Tao Yuzhu Liu Zhong Jin MOE Key Laboratory of Mesoscopic Chemistry MOE Key Laboratory of High Performance Polymer Materials and TechnologyJiangsu Key Laboratory of Advanced Organic MaterialsSchool of Chemistry and Chemical EngineeringNanjing UniversityNanjing 210023China Shenzhen Research Institute of Nanjing University Shenzhen 518063China

Phosphorene,especially black phosphorus(BP),has attracted considerable attention due to the unique characteristics,such as tunable direct bandgap,high carrier mobility,and strong in-plane ***,a new modification strategy for black phosphorus has been developed by alloying black phosphorus with the congener element *** elemental composition tuning of black phosphorus with arsenic can not only maintain its special crystal structure and high anisotropy but also modify its electrical and optical properties for the further applications of multifunctional *** achieved two-dimensional(2D)black arsenic-phosphorus materials exhibit outstanding optical,electrical,and photoelectric properties,such as very narrow band gap,anisotropic infrared absorption,and bipolar transfer characteristics,presenting great potential in infrared photodetectors and highperformance field effect transistors(FETs).In this review,we introduce the recent progress made in the synthesis and applications of black arsenic-phosphorus,and provide an outlook and perspectives on the current challenges and future opportunities in this *** hope that this review can bring new insights and inspirations on the further development of 2D black arsenic-phosphorus based materials and devices.

关键词： black arsenic-phosphorus two-dimensional(2D)materials black phosphorus field effect transistors mid-infrared photodetectors

Low-molecular-weight heparin and preeclampsia—does the sword cut both ways?Three case reports and review of literature

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World Journal of Clinical Cases 2024年第9期12卷 1634-1643页

作者： Dan Shan Tao Li Xi Tan Ya-yi hu Department of Obstetrics and Gynecology West China Second University HospitalSichuan UniversityChengdu 610000Sichuan ProvinceChina Key Laboratory of Birth Defects and Related Diseases of Women and Children Sichuan UniversityMinistry of EducationChengdu 610000SichuanChina

BACKGROUND Low-molecular-weight heparins(LMWH)are the most commonly used anticoagulants during *** is considered to be the drug of choice due to its safety in not crossing *** the beneficial effect in the improvement of microcirculation,prophylactic application of LMWH in patients with preeclampsia became a ***,the bleeding risk related with LMWH in preeclampsia patients has seldomly been *** current study aimed to identify the potential risks regarding LMWH application in patients with *** SUMMARY Herein we present a case series of three pregnant women diagnosed with preeclampsia on LMWH therapy during *** the cases experienced catastrophic hemorrhagic *** reviewing the twenty-one meta-analyses,the bleeding risk related with LMWH seems *** one study analyzed the bleeding risk of LMWH and found a significantly higher risk of developing PPH in women receiving *** studies reported minor bleeding risks,none of these were serious enough to stop LMWH *** of bleeding either from uterus or from intrabdominal organs in preeclampsia patients on LMWH therapy should not be *** management of blood pressure even after delivery and homeostasis suture in surgery are *** Consideration should be given to the balance between benefits and risks of LMWH in patients with preeclampsia.

关键词： Pregnancy Preeclampsia Low-molecular-weight heparin Hemorrhage Case report

Follicle-stimulating hormone as a predictor for sperm retrieval rate in patients with nonobstructive azoospermia, a systematic review and meta-analysis

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Asian Journal of Andrology 2015年第2期17卷 281-284,I0010页

作者： Qi Yang Yan-Ping huang Hong-Xiang Wang Kai hu yi-Xin Wang yi-Ran huang Bin Chen Department of Urology Ren Ji Hospital School of Medicine Shanghai Jiao Tong University Shanghai institute of Andrology Shanghai 200127 China.

Noninvasive parameters for predicating sperm retrieval rate （SRR） are desirables. Follicle-stimulating hormone （FSH） has been an important predictor since the first years of testicular sperm extraction. Recent studies showed continuous interests in FSH, with both pros and cons. Thus, we conducted a meta-analysis to evaluate the diagnostic value of FSH as a predictor for patients with nonobstructive azoospermia （NOA） taking testicular sperm retrieval. Eligible diagnosis tests were identified from electronic databases （Cochrane Central Register of Controlled Trials, Medline, and EMBASE） without language restrictions. The database search, quality assessment, and data extraction were performed independently by two reviewers. The reference standard was the sperm retrieval result. Diagnostic value of FSH were explored by area under receiver operation characteristics （ROC） curve using Review Manager, version 5.1.0 （Cochrane Collaboration, Oxford, UK） and Meta-DiSc, version 1.4. Meta regression will be done if there is heterogeneity. Then, we find 11 tests including a total of 1350 patients met the inclusion criteria. Our pooled analysis showed that the area under ROC curve of FSH was 0.72 ~ 0.04. Meta regression analyses showed that region and average age have an influence on the diagnostic value. FSH showed more diagnostic value with patients in East Asia and with younger patients. We concluded that FSH had moderate value in independently predicating SRR in men with NOA （area under curve 〉0.7）. More detailed diagnosis tests should be anticipated in the future to confirm the diagnostic value of other noninvasive parameters.

关键词： follicule-stimulating hormone meta-analysis nonobstructive azoospermia testicular sperm retrieval