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Progress on Transition Metal Ions Dissolution Suppression Strategies in Prussian Blue Analogs for Aqueous Sodium-/Potassium-Ion Batteries
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作者 Wenli Shu Junxian Li +3 位作者 Guangwan Zhang Jiashen Meng Xuanpeng Wang Liqiang Mai 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第7期142-168,共27页
Aqueous sodium-ion batteries(ASIBs)and aqueous potassium-ion batteries(APIBs)present significant potential for large-scale energy storage due to their cost-effectiveness,safety,and environmental compatibility.Nonethel... Aqueous sodium-ion batteries(ASIBs)and aqueous potassium-ion batteries(APIBs)present significant potential for large-scale energy storage due to their cost-effectiveness,safety,and environmental compatibility.Nonetheless,the intricate energy storage mechanisms in aqueous electrolytes place stringent require-ments on the host materials.Prussian blue analogs(PBAs),with their open three-dimensional framework and facile synthesis,stand out as leading candidates for aqueous energy storage.However,PBAs possess a swift capacity fade and limited cycle longevity,for their structural integrity is compromised by the pronounced dis-solution of transition metal(TM)ions in the aqueous milieu.This manuscript provides an exhaustive review of the recent advancements concerning PBAs in ASIBs and APIBs.The dissolution mechanisms of TM ions in PBAs,informed by their structural attributes and redox processes,are thoroughly examined.Moreover,this study delves into innovative design tactics to alleviate the dissolution issue of TM ions.In conclusion,the paper consolidates various strategies for suppressing the dissolution of TM ions in PBAs and posits avenues for prospective exploration of high-safety aqueous sodium-/potassium-ion batteries. 展开更多
关键词 Prussian blue analogs Transition metal ions dissolution Suppression strategies Aqueous sodium-ion batteries Aqueous potassium-ion batteries
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Experimental and computational optimization of Prussian blue analogues as high-performance cathodes for sodium-ion batteries:A review
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作者 Gwangeon Oh Junghoon Kim +4 位作者 Shivam Kansara Hyokyeong Kang Hun-Gi Jung Yang-Kook Sun Jang-Yeon Hwang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第6期627-662,I0015,共37页
In this review,we discuss the electrochemical properties of Prussian blue(PB)for Na^(+)storage by combining structural engineering and electrolyte modifications.We integrated experimental data and density functional t... In this review,we discuss the electrochemical properties of Prussian blue(PB)for Na^(+)storage by combining structural engineering and electrolyte modifications.We integrated experimental data and density functional theory(DFT)in sodium-ion battery(SIB)research to refine the atomic arrangements and crystal lattices and introduce substitutions and dopants.These changes affect the lattice stability,intercalation,electronic and ionic conductivities,and electrochemical performance.We unraveled the intricate structure-electrochemical behavior relationship by combining experimental data with computational models,including first-principles calculations.This holistic approach identified techniques for optimizing PB and Prussian blue analog(PBA)structu ral properties for SIBs.We also discuss the tuning of electrolytes by systematically adjusting their composition,concentration,and additives using a combination of molecular dynamics(MD)simulations and DFT computations.Our review offers a comprehensive assessment of strategies for enhancing the electrochemical properties of PB and PBAs through structural engineering and electrolyte modifications,combining experimental insights with advanced computational simulations,and paving the way for next-generation energy storage systems. 展开更多
关键词 Prussian blue analogs(PBAs) Sodium ion batteries(SIBs) Structural engineering Electrolyte modifications Experiments Density functional theory(DFT)
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An Adaptive Control Strategy for Energy Storage Interface Converter Based on Analogous Virtual Synchronous Generator
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作者 Feng Zhao Jinshuo Zhang +1 位作者 Xiaoqiang Chen Ying Wang 《Energy Engineering》 EI 2024年第2期339-358,共20页
In the DC microgrid,the lack of inertia and damping in power electronic converters results in poor stability of DC bus voltage and low inertia of the DC microgrid during fluctuations in load and photovoltaic power.To ... In the DC microgrid,the lack of inertia and damping in power electronic converters results in poor stability of DC bus voltage and low inertia of the DC microgrid during fluctuations in load and photovoltaic power.To address this issue,the application of a virtual synchronous generator(VSG)in grid-connected inverters control is referenced and proposes a control strategy called the analogous virtual synchronous generator(AVSG)control strategy for the interface DC/DC converter of the battery in the microgrid.Besides,a flexible parameter adaptive control method is introduced to further enhance the inertial behavior of the AVSG control.Firstly,a theoretical analysis is conducted on the various components of the DC microgrid,the structure of analogous virtual synchronous generator,and the control structure’s main parameters related to the DC microgrid’s inertial behavior.Secondly,the voltage change rate tracking coefficient is introduced to adjust the change of the virtual capacitance and damping coefficient flexibility,which further strengthens the inertia trend of the DC microgrid.Additionally,a small-signal modeling approach is used to analyze the approximate range of the AVSG’s main parameters ensuring system stability.Finally,conduct a simulation analysis by building the model of the DC microgrid system with photovoltaic(PV)and battery energy storage(BES)in MATLAB/Simulink.Simulation results from different scenarios have verified that the AVSG control introduces fixed inertia and damping into the droop control of the battery,resulting in a certain level of inertia enhancement.Furthermore,the additional adaptive control strategy built upon the AVSG control provides better and flexible inertial support for the DC microgrid,further enhances the stability of the DC bus voltage,and has a more positive impact on the battery performance. 展开更多
关键词 Adaptive control analogous virtual synchronous generator DC/DC converter inertia of DC microgrid DC microgrid with PV and BES BATTERY DC bus voltage
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Treatment of central precocious puberty by GnRH analogs: long-term outcome in men 被引量:13
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作者 Silvano Bertelloni Dick Mul 《Asian Journal of Andrology》 SCIE CAS CSCD 2008年第4期525-534,共10页
In boys, central precocious puberty (CPP) is the appearance of secondary sex characteristics driven by pituitary gonadotropin secretion before the age of 9 years. In the last years, relevant improvements in the trea... In boys, central precocious puberty (CPP) is the appearance of secondary sex characteristics driven by pituitary gonadotropin secretion before the age of 9 years. In the last years, relevant improvements in the treatment of CPP have been achieved. Because CPP is rare in boys, the majority of papers on this issue focus on girls and do not address specific features of male patients regarding end results and safety. In the present paper, recent advances of CPP management with GnRH analogs in men are summarized. End results in untreated and treated patients are also reviewed by an analysis of the recently published literature on treatment of CPP in men. The available data indicate that therapy with GnRH analogs can improve final height into the range of target height without significant adverse short-term and long-term effects, but longer follow-up of larger series of patients is still required to draw definitive conclusions. 展开更多
关键词 ADOLESCENT MALE central precocious puberty gonadotropin-releasing hormone analog treatment gonadotropin-releasing hormone analog safety long-term outcome adult height
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Studies on the Synthesis of a Natural Product-Piceatannol and its Analogs 被引量:4
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作者 Zhi Song PIAO Lin WANG +1 位作者 Ya Bin FENG Zhi Zhong ZHAO 《Chinese Chemical Letters》 SCIE CAS CSCD 2002年第6期521-524,共4页
Piceatannol, (E)-3, 3, 4, 5-tetrahydroxy stilbene, a natural polyhydroxy stilbene, possesses many biological activities, its synthesis has been reported. We designed another route of its synthesis, which can be contr... Piceatannol, (E)-3, 3, 4, 5-tetrahydroxy stilbene, a natural polyhydroxy stilbene, possesses many biological activities, its synthesis has been reported. We designed another route of its synthesis, which can be controlled more easily. The synthetic product was characterized by elemental analysis, IR, MS and 1H-NMR. Its analogs were synthesized by the similar method. 展开更多
关键词 Total synthesis PICEATANNOL analogs.
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Isomerization of n-pentane catalyzed by amide-AlCl3-based ionic liquid analogs with various additives 被引量:2
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作者 Pengcheng Hu Jingwei Zheng +2 位作者 Wei Jiang Lijuan Zhong Shufeng Zhou 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2020年第1期152-157,共6页
The isomerization of n-pentane to generate high-quality blending components for clean gasoline was catalyzed by several amide-AlCl3-based ionic liquid(IL) analogs with various amides as donor molecules. The catalytic ... The isomerization of n-pentane to generate high-quality blending components for clean gasoline was catalyzed by several amide-AlCl3-based ionic liquid(IL) analogs with various amides as donor molecules. The catalytic performance of these IL analogs was evaluated in a magnetic agitated autoclave operated in batch mode.IL analog based n-methylacetamide(NMA)-AlCl3 with the amide/AlCl3 molar ratio of 0.65 showed excellent performance toward n-pentane isomerization because 0.65 NMA-1.0 AlCl3 had a low viscosity and bidentate coordination structure. The influences of reaction time, reaction temperature, and stirring speed on the catalytic performance were also investigated. Optimal reaction conditions comprised the reaction time of 1 h, the reaction temperature of 40 °C, and the stirring speed of 1500 r·min-1. Under optimal condition, the n-C5 conversion,research octane number(RON) increment, total liquids yield, and isoparaffin yield in isomerized oil were56.80%, 13.51, 89.90 wt%, and 44.32 wt%, respectively. A new mathematical model was constructed to predict the relationships among RON increment, RON increment/n-C5 conversion ratio, and n-C5 conversion. The new model indicated that an appropriate conversion per pass of n-C5 did not exceed 50%–55%. Various cycloparaffin additives were used to improve the catalytic performance of 0.65 NMA-1.0 AlCl3. The n-C5 conversion increased from 56.80% to 67.32%. The RON increment, total liquids yield, and isoparaffin yield reached 17.83, 97.36 wt%,and 63.74 wt%, respectively. 展开更多
关键词 ISOMERIZATION Ionic liquid analogs N-PENTANE Mathematical model ADDITIVES
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Determination of structure-activity relationships between fentanyl analogs and human μ-opioid receptors based on active binding site models 被引量:3
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作者 Ming Liu Xiaoli Liu +2 位作者 Ping Wan Qiangsan Wu Wenxiang Hu 《Neural Regeneration Research》 SCIE CAS CSCD 2011年第4期267-276,共10页
Fentanyl is a potent and widely used clinical narcotic analgesic, as well as a highly selective IJ-opioid agonist. The present study established a homologous model of the human μ-opioid receptor; an intercomparison o... Fentanyl is a potent and widely used clinical narcotic analgesic, as well as a highly selective IJ-opioid agonist. The present study established a homologous model of the human μ-opioid receptor; an intercomparison of three types of μ-opioid receptor protein sequence homologous rates was made. The secondary receptor structure was predicted, the model reliability was assessed and verified using the Ramachandran plot and ProTab analysis. The predictive ability of the CoMFA model was further validated using an external test set. Using the Surflex-Dock program, a series of fentanyl analog molecules were docked to the receptor, the calculation results from Biopolymer/SitelD showed that the receptor had a deep binding area situated in the extracellular side of the transmembrane domains (TM) among TM3, TM5, TM6, and TMT. Results suggested that there might be 5 active areas in the receptor. The important residues were Asp147, Tyr148, and Tyr149 in TM3, Trp293, and His297 in TM6, and Trp318, His319, Ile322, and Tyr326 in TM7, which were located at the 5 active areas. The best fentanyl docking orientation position was the piperidine ring, which was nearly perpendicular to the membrane surface in the 7 TM domains. Molecular dynamic simulations were applied to evaluate potential relationships between ligand conformation and fentanyl substitution. 展开更多
关键词 μ-opioid receptor fentanyl analogs AGONIST active site structure-activity relationship
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Studies on the Synthesis of Pyridine Analogs of the Natural Product3,5,4'-Trimethoxystilbene 被引量:2
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作者 Zhi Song PIAO Lin WANG Zhi Zhong ZHAO 《Chinese Chemical Letters》 SCIE CAS CSCD 2003年第11期1119-1122,共4页
Five pyridine analogs of the natural product, 3, 5, 4'-trimethoxystilbene, were synthesized. The final compounds were characterized by 1H-NMR.
关键词 SYNTHESIS pyridine analogs of 3 5 4'-trimethoxystilbene .
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THE PREPARATION AND BIOACTIVITIES OF OPTICALANALOGS OF BAOGONGTENG A 被引量:2
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作者 杨丽敏 王惠宁 严忠红 《Medical Bulletin of Shanghai Jiaotong University》 CAS 1999年第1期51-53,共3页
objective We prepared optical analogs of Baogongteng A and investigated their bioactivities soas to find new effective hypotoxic drugs at M- receptors. Methods Racemic analogs of Baogongteng A wereresolved with chiral... objective We prepared optical analogs of Baogongteng A and investigated their bioactivities soas to find new effective hypotoxic drugs at M- receptors. Methods Racemic analogs of Baogongteng A wereresolved with chiral acid. Results Six chiral analogs of Baogongteng A were prepared. In mydriatic tests inrabbits, (+) - 32 - benzoyloxy - 6β - acetoxytropane and (+) - 32 - parachloro benzoyloxy- 6β- acetoxytropanepossess anticholinergic activities. Conclusion The configuration of enantiomers has significant influence on thebioactivity of analogs of Baogongteng A. 展开更多
关键词 analogs of Baogongteng A CHIRAL MEDICINE ANTICHOLINERGIC ACTIVITY
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Synthesis and Antibacterial Activity of Novel Oxazolidinone Analogs Containing Substituted Thiazole/Fused-Bicyclic Groups 被引量:1
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作者 ZHAI Xin ZHAO Yan-fang WANG Jia HONG Wei HUANG Liang GONG Ping 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2006年第4期459-464,共6页
Sixteen novel oxazolidinone analogs containing substituted thiazole/fused-bicyclic(imidazo[ 1,2-b] pyridazine/ imidazo[2,1-b] thiazole) groups were designed and synthesized. A new method for the preparation of the k... Sixteen novel oxazolidinone analogs containing substituted thiazole/fused-bicyclic(imidazo[ 1,2-b] pyridazine/ imidazo[2,1-b] thiazole) groups were designed and synthesized. A new method for the preparation of the key intermediate compound 11 was proposed. The structures of the target compounds were confirmed by ^1H NMR, IR and MS, and their in vitro antibacterial activities against staphylococcus aureus were evaluated. Among them, compound 16a displays a promising antibacterial activity comparable to that of linezolid. 展开更多
关键词 Oxazolidinone analog SYNTHESIS Antibacterial activity
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Synthesis and antibacterial activity of 4″-O-carbamoyl analogs of clarithromycin 被引量:3
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作者 Xue Cui Shen Bo Jiao Shu Tao Ma 《Chinese Chemical Letters》 SCIE CAS CSCD 2010年第3期257-260,共4页
A series of novel 4'-O-carbamoyl analogs of clarithromycin were synthesized and evaluated for their in vitro antibacterial activity. All of the desired compounds showed excellent activity against erythromycin-susc... A series of novel 4'-O-carbamoyl analogs of clarithromycin were synthesized and evaluated for their in vitro antibacterial activity. All of the desired compounds showed excellent activity against erythromycin-susceptible S.pneumoniae.Particularly,4-fluorobenzyl carbamate 7a demonstrated potent activity against erythromycin-resistant S.pneumoniae encoded by the mef gene,and remarkably improved activity against erythromycin-resistant S.pneumoniae encoded by the erm gene,and the erm and mef genes. 展开更多
关键词 Clarithromycin analogs 4″-O-carbamate SYNTHESIS Antibacterial activity Resistant bacteria
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Effects of glucagon-like peptide 1 analogs in combination with insulin on myocardial infarct size in rats with type 2 diabetes mellitus 被引量:1
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作者 Vladislav A Zykov Taisiia P Tuchina +6 位作者 Denis A Lebedev Irina B Krylova Alina Y Babenko Elvira V Kuleshova Elena N Grineva Alekber A Bayramov Michael M Galagudza 《World Journal of Diabetes》 SCIE CAS 2018年第9期149-156,共8页
AIM To evaluate the effects of glucagon-like peptide-1 analogs(GLP-1 a) combined with insulin on myocardial ischemiareperfusion injury in diabetic rats.METHODS Type 2 diabetes mellitus(T2 DM) was induced in maleWistar... AIM To evaluate the effects of glucagon-like peptide-1 analogs(GLP-1 a) combined with insulin on myocardial ischemiareperfusion injury in diabetic rats.METHODS Type 2 diabetes mellitus(T2 DM) was induced in maleWistar rats with streptozotocin(65 mg/kg) and verified using an oral glucose tolerance test. After anesthesia, the left coronary artery was occluded for 40 min followed by 80 min reperfusion. Blood glucose level was measured during surgery. Rats were randomized into six groups as follows:(1) control rats;(2) insulin(0.1 U/kg) treated rats prior to ischemia;(3) insulin(0.1 U/kg) treated rats at reperfusion;(4) GLP-1 a(140 mg/kg) treated rats prior to ischemia;(5) GLP-1 a(140 mg/kg) treated rats at reperfusion; and(6) rats treated with GLP-1 a(140 mg/kg) prior to ischemia plus insulin(0.1 U/kg) at reperfusion. Myocardial area at risk and infarct size was measured planimetrically using Evans blue and triphenyltetrazolium chloride staining, respectively.RESULTS There was no significant difference in the myocardial area at risk among groups. Insulin treatment before ischemia resulted in a significant increase in infarct size(34.7% ± 3.4% vs 18.6% ± 3.1% in the control rats, P < 0.05). Post-ischemic administration of insulin or GLP-1 a had no effect on infarct size. However, pre-ischemic administration of GLP-1 a reduced infarct size to 12% ± 2.2%(P < 0.05). The maximal infarct size reduction was observed in the group treated with GLP-1 a prior to ischemia and insulin at reperfusion(8% ± 1.6%, P < 0.05 vs the control and GLP-1 a alone treated groups).CONCLUSION GLP-1 a pre-administration results in myocardial infarct size reduction in rats with T2 DM. These effects are maximal in rats treated with GLP-1 a pre-ischemia plus insulin at reperfusion. 展开更多
关键词 Glucagon-like peptide-1 analog INSULIN Myocardial ISCHEMIA-REPERFUSION injury INFARCT size Type 2 diabetes mellitus RATS Experimental research
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3D-QSAR Studies on 3-Substituted N-Benzhydryl-nortropane Analogs as Nociception Receptor Agonists 被引量:2
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作者 苗俊秋 何素海 +2 位作者 董秀山 梁泰刚 李青山 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2016年第9期1319-1327,共9页
The nociceptin receptor(NOP) has been involved in multiple biological functions, including pain, anxiety, cough, substance abuse, cardiovascular control, and immunity. Thus, selective NOP agonists might have clinica... The nociceptin receptor(NOP) has been involved in multiple biological functions, including pain, anxiety, cough, substance abuse, cardiovascular control, and immunity. Thus, selective NOP agonists might have clinical potential for the treatment of related diseases. In the present work, three-dimensional quantitative structure-activity relationship(3D-QSAR) studies were performed on a series of 3-substituted N-benzhydryl-nortropane analogs as NOP agonists using comparative molecular field analysis(Co MFA) and comparative molecular similarity indices analysis(CoM SIA) techniques. The statistically significant models were obtained with 54 compounds in training set by ligand-based atom-by-atom matching alignment. The CoM FA model gave cross-validated coefficient(q2) value of 0.530 using 6 components, non-cross-validated(r2) value of 0.921 with estimated F value of 93.668, and standard error of estimate(SEE) of 0.185. The best Co MSIA model resulted in q2 = 0.592, r2 = 0.945, N = 10, SEE = 0.162, and F = 75.654, based on steric, electrostatic, hydrophobic and hydrogen bond acceptor fields. The predictive ability of the Co MFA and CoM SIA models was further validated using a test set of 18 molecules that were not included in the training set, which resulted in predictive correlation coefficients(r2pred) of 0.551 and 0.637, respectively. Moreover, the CoM FA and CoM SIA contour maps identified the features important for exhibiting potent binding affinities on NOP, and can thus serve as a useful guide for the design of potential NOP agonists. 展开更多
关键词 QSAR CoMFA CoMSIA 3-substituted N-benzhydryl-nortropane analogs nociception receptor agonists
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Hepatocellular carcinoma progression in hepatitis B virus-related cirrhosis patients receiving nucleoside(acid)analogs therapy:A retrospective cross-sectional study 被引量:2
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作者 Dan-Hong Yang Wei-Ping Wang +3 位作者 Qiang Zhang Hong-Ying Pan Yi-Cheng Huang Jia-Jie Zhang 《World Journal of Gastroenterology》 SCIE CAS 2021年第17期2025-2038,共14页
BACKGROUND Antiviral therapy cannot completely block the progression of hepatitis B to hepatocellular carcinoma(HCC).Furthermore,there are few predictors of early HCC progression and limited strategies to prevent prog... BACKGROUND Antiviral therapy cannot completely block the progression of hepatitis B to hepatocellular carcinoma(HCC).Furthermore,there are few predictors of early HCC progression and limited strategies to prevent progression in patients with HBV-related cirrhosis who receive nucleos(t)ide analog(NA)therapy.AIM The study aim was to clarify risk factors and the diagnostic value of alphafetoprotein(AFP)for HCC progression in NA-treated hepatitis B virus(HBV)-related cirrhosis patients.METHODS In this retrospective cross-sectional study,we analyzed the clinical data of 266 patients with HBV-related cirrhosis who received NA treatment between February 2014 and April 2020 at Zhejiang Provincial People’s Hospital.The patients were divided into two groups,145 who did not progress to HCC(No-HCC group),and 121 who progressed to HCC during NA treatment(HCC group).The logistic regression analysis was used to analyze the risk factors of HCC progression.The diagnostic value of AFP for HCC was evaluated by receiver operating characteristic(ROC)curve analysis.RESULTS Univariate analysis showed that age≥60 years(P=0.001),hepatitis B and alcoholic etiology(P=0.007),smoking history(P<0.001),family history of HBV-related HCC(P=0.002),lamivudine resistance(P=0.011),HBV DNA negative(P=0.023),aspartate aminotransferase>80 U/L(P=0.002),gamma-glutamyl transpeptidase>120 U/L(P=0.001),alkaline phosphatase>250 U/L(P=0.001),fasting blood glucose(FBG)≥6.16(mmol/L)(P=0.001)and Child-Pugh class C(P=0.005)were correlated with HCC progression.In multivariate analysis,age≥60 years[hazard ratio(HR)=3.089,95%confidence interval(CI):1.437-6.631,P=0.004],smoking history(HR=4.001,95%CI:1.836-8.716,P<0.01),family history of HBV-related HCC(HR=6.763,95%CI:1.253-36.499,P<0.05),lamivudine resistance(HR=2.949,95%CI:1.207-7.208,P=0.018),HBV DNA negative(HR=0.026,95%CI:0.007-0.139,P<0.01),FBG≥6.16 mmol/L(HR=7.219,95%CI:3.716-14.024,P<0.01)were independent risk factors of HCC progression.ROC of AFP for diagnosis of HCC was 0.746(95%CI:0.674-0.818).A cutoff value of AFP of 9.00 ug/L had a sensitivity of 0.609,and specificity of 0.818 for diagnosing HCC.CONCLUSION Age≥60 years,smoking history,family history of HCC,lamivudine resistance,HBV DNA negative,FBG≥6.16 mmol/L were risk factors of HCC progression.Serum AFP had limited diagnostic value for HCC. 展开更多
关键词 Hepatitis B virus Hepatocellular carcinoma CIRRHOSIS Risk factors Nucleos(t)ide analogs PROGRESSION
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Exploration of nucleos(t)ide analogs cessation in chronic hepatitis B patients with hepatitis B e antigen loss 被引量:1
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作者 Yan Xue Meng Zhang +5 位作者 Tao Li Feng Liu Li-Xin Zhang Xiao-Ping Fan Bao-Hua Yang Lei Wang 《World Journal of Gastroenterology》 SCIE CAS 2021年第14期1497-1506,共10页
BACKGROUND Nucleos(t)ide analogs(NAs)cessation in chronic hepatitis B(CHB)patients remains a matter of debate in clinical practice.Current guidelines recommend that patients with hepatitis B e antigen(HBeAg)seroconver... BACKGROUND Nucleos(t)ide analogs(NAs)cessation in chronic hepatitis B(CHB)patients remains a matter of debate in clinical practice.Current guidelines recommend that patients with hepatitis B e antigen(HBeAg)seroconversion discontinue NAs after relatively long-term consolidation therapy.However,many patients fail to achieve HBeAg seroconversion after the long-term loss of HBeAg,even if hepatitis B surface antigen(HBsAg)loss occurs.It remains unclear whether NAs can be discontinued in this subset of patients.AIM To investigate the outcomes and factors associated with HBeAg-positive CHB patients with HBeAg loss(without hepatitis B e antibody)after cessation of NAs.METHODS We studied patients who discontinued NAs after achieving HBeAg loss.The Cox proportional hazards model was used to identify predictors for virological relapse after cessation of NAs.The cut-off value of the consolidation period was confirmed using receiver operating characteristic curves;we confirmed the cut-off value of HBsAg according to a previous study.The log-rank test was used to compare cumulative relapse rates among groups.We also studied patients with CHB who achieved HBeAg seroconversion and compared their cumulative relapse rates.Propensity score matching analysis(PSM)was used to balance baseline characteristics between the groups.RESULTS We included 83 patients with HBeAg loss.The mean age of these patients was 32.1±9.5 years,and the majority was male(67.5%).Thirty-eight patients relapsed,and the cumulative relapse rate at months 3,6,12,24,36,60,120,and 180 were 22.9%,36.1%,41.0%,43.5%,45.0%,45.0%,45.0%,and 52.8%,respectively.Twentysix(68.4%)patients relapsed in the first 3 mo after NAs cessation,and 35 patients(92.1%)relapsed in the first year after NAs cessation.Consolidation period(≥24 mo vs<24 mo)(HR 0.506,P=0.043)and HBsAg at cessation(≥100 IU/mL vs<100 IU/mL)(HR 14.869,P=0.008)were significant predictors in multivariate Cox regression.In the PSM cohort,which included 144 patients,there were lower cumulative relapse rates in patients with HBeAg seroconversion(P=0.036).CONCLUSION HBeAg-positive CHB patients with HBeAg loss may be able to discontinue NAs therapy after long-term consolidation,especially in patients with HBsAg at cessation<100 IU/mL.Careful monitoring,especially in the early stages after cessation,may ensure a favorable outcome. 展开更多
关键词 Chronic hepatitis B Hepatitis B e antigen Nucleos(t)ide analogs CESSATION
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Conformation Analysis and Comparison of Epristeride(17β-N-t-Butylcarboxamide-androst-3,5-diene-3-carboxylic Acid) and Its Analogs
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作者 YAO Li-xin 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2005年第5期525-527,共3页
Conformations of Epristeride( 17-β-N-t-butylcarboxamide-androst-3,5-diene-3-carboxylic acid) and its analogs were analyzed with the random search method and compared by means of the methods for steroid conformers, ... Conformations of Epristeride( 17-β-N-t-butylcarboxamide-androst-3,5-diene-3-carboxylic acid) and its analogs were analyzed with the random search method and compared by means of the methods for steroid conformers, Connolly surfaces, dihedral angles, and molecular accessibility probes with protons, hydroxyl and methyl groups contained simultaneously. Analog d is different from others, which is in accordance with the preliminary clinical trial results under double blind conditions. 展开更多
关键词 Epristeride Conformation analysis Molecular accessibility analog
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Synthesis of Analogs of Anacardosidefrom Sem ecarpusAnacardium
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作者 WANG Yu-lan CAI Meng-shen 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 1999年第3期294-299,共6页
关键词 analogs of anacardoside SYNTHESIS Phenolic glycoside DISACCHARIDE
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Synthesis and Anti-HIV Activity of Trisubstituted (3′R, 4′R)-3′,4′- Di-O-(S)-camphanoyl-(+)-cis-khellactone (DCK) Analogs
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作者 Chun Hong ZHAO Ting ZHOU +4 位作者 Lan XIE Jing Yun LI Zuo Yi BAO Zhao Wen LOU Kuo Hsiung LEE 《Chinese Chemical Letters》 SCIE CAS CSCD 2005年第10期1297-1300,共4页
To further explore the potential of DCK analogs as anti-HIV drug candidates, ten new tri-substituted (3'R,4'R)-3',4'-di-O-(S)-camphanoyl-(+)-cis-khellactone (DCK) derivatives (4-13) were designed, synth... To further explore the potential of DCK analogs as anti-HIV drug candidates, ten new tri-substituted (3'R,4'R)-3',4'-di-O-(S)-camphanoyl-(+)-cis-khellactone (DCK) derivatives (4-13) were designed, synthesized, and evaluated against HIV replication in MT4 cells and H9 lympho- cytes. 展开更多
关键词 anti-HIV agent DCK analogs synthesis.
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Characteristic fragmentation behavior of the analogs of endomorphin-2 with phenylglycine in position 3 or 4 by ESI-FT tandem mass spectrometry
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作者 Chang Feng Hu Chuan Jun Zhu +3 位作者 Yan Feng Gao Xuan Shao Rui Wang Yu Xin Cui 《Chinese Chemical Letters》 SCIE CAS CSCD 2008年第12期1479-1482,共4页
A series of analogs of endomorphin-2 (EM-2) with phenylglycine (Phg) in position 3 or 4 were synthesized. In electrospray ionization Fourier transform ion cyclotron resonance (ESI-Fr-ICR) MS/MS spectra of these ... A series of analogs of endomorphin-2 (EM-2) with phenylglycine (Phg) in position 3 or 4 were synthesized. In electrospray ionization Fourier transform ion cyclotron resonance (ESI-Fr-ICR) MS/MS spectra of these compounds, some b, y, a, and internal ions were observed and slight mass differences between the calculated and observed results are obtained. Their sequences were derived successfully. However, the MS/MS patterns of these analogs with Dphg and Lphg were very similar. It is hard to distinguish them by MS/MS spectra. Moreover, if the third position was substituted by phenylglycine (L or D), a rearrangement could occur in MS/MS experiment to lose proline residue. 展开更多
关键词 Endomorphin-2 Opioid peptide analogs PHENYLGLYCINE ESI-FT MS
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Synthesis and Insecticidal Activity of Novel Camptothecin Derivatives Containing Analogs of Chrysanthemic Acid Moieties
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作者 DENG Li ZHANG Lan +4 位作者 CAO Li-dong XIE Ru-liang ZHANG Yan-ning HE Wei-zhi JIANG Hong-yun 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2014年第6期1320-1330,共11页
Creating high-efifcient and environment-friendly pesticides is very important to produce the pollution free agriculture food and maintain the balance of the survival environmental of the human being. According to repo... Creating high-efifcient and environment-friendly pesticides is very important to produce the pollution free agriculture food and maintain the balance of the survival environmental of the human being. According to reports, camptothecin (CPT) and its derivatives are now being explored as a class of botanical insecticide in agriculture due to its novel mode of action. In order to improve the insecticidal activity of CPT, ten novel camptothecin (1) and 10-hydroxycamptothecin (2) derivatives (1a, 1b, 1c, 1d, 1e;2a, 2b, 2c, 2d, 2e) were designed and synthesized via esteriifcation with analogs of chrysanthemic acid, which have outstanding insecticidal activity. The results showed that compound 2a exhibited potent antifeeding effect and the best contact toxicity among the target compounds against the third-instar larvae of beet armyworm, Spodoptera exigua H&#252;bner. Compound 2a was also found to be the most effective cytotoxic compound to the tested insect cell lines, IOZCAS-Spex-II, which were established from the fat bodies of S. exigua. It was proposed that the 10-hydroxyl group in the camptothecin derivatives is a key factor for the antifeeding activity of a compound. The nature of the substituents was considered the major factor in determining the insecticidal activity of these compounds. 展开更多
关键词 CAMPTOTHECIN analogs of chrysanthemic acid SYNTHESIS antifeeding activity contact toxicity CYTOTOXICITY
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