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Memory effect in time fractional Schrödinger equation
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作者 祖传金 余向阳 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第2期216-221,共6页
A significant obstacle impeding the advancement of the time fractional Schrodinger equation lies in the challenge of determining its precise mathematical formulation.In order to address this,we undertake an exploratio... A significant obstacle impeding the advancement of the time fractional Schrodinger equation lies in the challenge of determining its precise mathematical formulation.In order to address this,we undertake an exploration of the time fractional Schrodinger equation within the context of a non-Markovian environment.By leveraging a two-level atom as an illustrative case,we find that the choice to raise i to the order of the time derivative is inappropriate.In contrast to the conventional approach used to depict the dynamic evolution of quantum states in a non-Markovian environment,the time fractional Schrodinger equation,when devoid of fractional-order operations on the imaginary unit i,emerges as a more intuitively comprehensible framework in physics and offers greater simplicity in computational aspects.Meanwhile,we also prove that it is meaningless to study the memory of time fractional Schrodinger equation with time derivative 1<α≤2.It should be noted that we have not yet constructed an open system that can be fully described by the time fractional Schrodinger equation.This will be the focus of future research.Our study might provide a new perspective on the role of time fractional Schrodinger equation. 展开更多
关键词 time fractional Schrodinger equation memory effect non-Markovian environment
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The superiority of PMFs on reversing drug resistance of colon cancer and the effect on aerobic glycolysis-ROS-autophagy signaling axis
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作者 YUQIN YIN YU WU +6 位作者 HONGLIANG HUANG YINGYING DUAN ZHONGWEN YUAN LIHUI CAO JINJIN YING YONGHENG ZHOU SENLING FENG 《Oncology Research》 SCIE 2024年第12期1891-1902,共12页
Background:Polymethoxylatedflavones(PMFs)are compounds present in citrus peels and other Rutaceae plants,which exhibit diverse biological activities,including robust antitumor and antioxidant effects.However,the mechan... Background:Polymethoxylatedflavones(PMFs)are compounds present in citrus peels and other Rutaceae plants,which exhibit diverse biological activities,including robust antitumor and antioxidant effects.However,the mechanism of PMFs in reversing drug resistance to colon cancer remains unknown.In the present study,we aimed to investigate the potential connection between the aerobic glycolysis-ROS-autophagy signaling axis and the reversal of PTX resistance in colon cancer by PMFs.Methods:MTT Cell viability assay and colony formation assay were used to investigate the effect of PMFs combined with PTX in reversing HCT8/T cell resistance ex vivo;the mRNA and protein levels of the target were detected by SDS-PAGE(sodium dodecyl sulfate-polyacrylamide gel electrophoresis),quantitative real-timefluorescence polymerase chain reaction(qRT-PCR)and Western blot protein immunoblotting(WB);An HCT8/T cell xenograft model was established to investigate the MDR reversal activity of PMFs in vivo;The extracellular acidification rate(ECAR)and the oxygen consumption rate(OCR)were detected to assess the cellular oxygen consumption rate and glycolytic process.Results:HCT8/T cells demonstrated significant resistance to PTX,up-regulating the expression levels of ABCB1 mRNA,P-gp,LC3-I,and LC3-II protein,and increasing intracellular reactive oxygen species(ROS)content.PMFs mainly contain two active ingredients,nobiletin,and tangeretin,which were able to reverse drug resistance in HCT8/T cells in a concentration-dependent manner.PMFs exhibited high tolerance in the HCT8/T nude mouse model while increasing the sensitivity of PTX-resistant cells and suppressing tumor growth significantly.PMFs combined with PTX reduced extracellular acidification rate(ECAR)and oxygen consumption rate(OCR)in HCT8/T cells.Additionally,PMFs reduced intracellular ROS content,down-regulated the expression levels of autophagy-related proteins LC3-I,LC3-II,Beclin1,and ATG7,and significantly reduced the number of autophagosomes in HCT8/T cells.Conclusions:The present study demonstrated that PMFs could potentially reverse PTX resistance in colon cancer by regulating the aerobic glycolysis-ROS-autophagy signaling axis,which indicated that PMFs would be potential potentiators for future chemotherapeutic agents in colon cancer. 展开更多
关键词 Polymethoxylated flavones(PMFs) Colon cancer drug resistance Aerobic glycolysis-ROS-autophagy Warburg effect
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Kongsheng Zhenzhong pill's effect on the learning and memory ability and its neuroprotective effects in vascular dementia rats 被引量:3
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作者 Xuming Ji Huayun Yu +4 位作者 Bin Ouyang Guowei Liu Zhichun Wu Heng Liu Fang Du 《Neural Regeneration Research》 SCIE CAS CSCD 2011年第30期2342-2346,共5页
Clinical reports have demonstrated that the Kongsheng Zhenzhong pill (KSZZP), a classical prescription deriving from Valuable Prescription for Emergencies, has good therapeutic effects on vascular dementia. However,... Clinical reports have demonstrated that the Kongsheng Zhenzhong pill (KSZZP), a classical prescription deriving from Valuable Prescription for Emergencies, has good therapeutic effects on vascular dementia. However, the mechanisms that mediate its effects remain unclear. In this study, the expression of N-methyI-D-aspartate receptor 1 mRNA, the content of nitric oxide, and the concentration of calcium in neurons was determined with in situ hybridization, spectrophotometry and flow cytometry, respectively. In addition, the expressions of N-methyI-D-aspartate receptor 1, nerve growth factor protein, and glial cell line-derived neurotrophic factor protein were detected with immunohistochemistry. We found that KSZZP could significantly decrease the expression of N-methyI-D-aspartate receptor 1 mRNA and protein, the content of nitric oxide, and the concentration of calcium in neurons. KSZZP also increased the expression of nerve growth factor and glial cell line-derived neurotrophic factor protein in the hippocampus CA1 region and in the cerebral cortex. Morris water maze and passive avoidance tests verified that KSZZP ameliorated the cognitive impairments of vascular dementia rats. Moreover, the KSZZP-induced improvements in the cognitive functions of vascular dementia rats were correlated with both inhibition of N-methyl-D-aspartate-induced excitable neurotoxicity and elevation of neurotrophic factor expression. 展开更多
关键词 Kongsheng Zhenzhong pill vascular dementia learning and memory ability neuroprotective effects
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Vitamin D,selenium,and antidiabetic drugs in the treatment of type 2 diabetes mellitus with Hashimoto's thyroiditis 被引量:2
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作者 Fen Feng Bin Zhou +3 位作者 Ci-La Zhou Ping Huang Gang Wang Kuang Yao 《World Journal of Diabetes》 SCIE 2024年第2期209-219,共11页
BACKGROUND Diabetes and thyroiditis are closely related.They occur in combination and cause significant damage to the body.There is no clear treatment for type-2 diabetes mellitus(T2DM)with Hashimoto's thyroiditis... BACKGROUND Diabetes and thyroiditis are closely related.They occur in combination and cause significant damage to the body.There is no clear treatment for type-2 diabetes mellitus(T2DM)with Hashimoto's thyroiditis(HT).While single symptomatic drug treatment of the two diseases is less effective,combined drug treatment may improve efficacy.AIM To investigate the effect of a combination of vitamin D,selenium,and hypoglycemic agents in T2DM with HT.METHODS This retrospective study included 150 patients with T2DM and HT treated at The Central Hospital of Shaoyang from March 2020 to February 2023.Fifty patients were assigned to the control group,test group A,and test group B according to different treatment methods.The control group received low-iodine diet guidance and hypoglycemic drug treatment.Test group A received the control treatment plus vitamin D treatment.Test group B received the group A treatment plus selenium.Blood levels of markers of thyroid function[free T3(FT3),thyroid stimulating hormone(TSH),free T4(FT4)],autoantibodies[thyroid peroxidase antibody(TPOAB)and thyroid globulin antibody(TGAB)],blood lipid index[low-density lipoprotein cholesterol(LDL-C),total cholesterol(TC),triacylglycerol(TG)],blood glucose index[fasting blood glucose(FBG),and hemoglobin A1c(HbA1c)]were measured pre-treatment and 3 and 6 months after treatment.The relationships between serum 25-hydroxyvitamin D3[25(OH)D3]level and each of these indices were analyzed.RESULTS The levels of 25(OH)D3,FT3,FT4,and LDL-C increased in the order of the control group,test group A,and test group B(all P<0.05).The TPOAB,TGAB,TC,TG,FBG,HbA1c,and TSH levels increased in the order of test groups B,A,and the control group(all P<0.05).All the above indices were compared after 3 and 6 months of treatment.Pre-treatment,there was no divergence in serum 25(OH)D3 level,thyroid function-related indexes,autoantibodies level,blood glucose,and blood lipid index between the control group,test groups A and B(all P>0.05).The 25(OH)D3 levels in test groups A and B were negatively correlated with FT4 and TGAB(all P<0.05).CONCLUSION The combination drug treatment for T2DM with HT significantly improved thyroid function,autoantibody,and blood glucose and lipid levels. 展开更多
关键词 Type-2 diabetes mellitus Hashimoto's thyroiditis Vitamin D Selenium agent Hypoglycemic drugs Curative effect
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EFFECTS OF HEAT TREATMENT ON TENSILE PROPERTIES AND SHAPE MEMORY EFFECTS OF Ni-Ti-Nb ALLOY 被引量:2
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作者 Zheng Yufeng, Cai Wei, Luo Yichun, Zhao Liancheng School of Materials Science and Engineering, Harbin Institute of Technology, Harbin 150001 《中国有色金属学会会刊:英文版》 CSCD 1997年第4期93-97,共5页
EFFECTSOFHEATTREATMENTONTENSILEPROPERTIESANDSHAPEMEMORYEFFECTSOFNiTiNbALLOY①ZhengYufeng,CaiWei,LuoYichun,Z... EFFECTSOFHEATTREATMENTONTENSILEPROPERTIESANDSHAPEMEMORYEFFECTSOFNiTiNbALLOY①ZhengYufeng,CaiWei,LuoYichun,ZhaoLianchengSchoo... 展开更多
关键词 Ni Ti Nb ALLOY HEAT treatment TENSILE PROPERTIES SHAPE memory effect
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Effects of Predeformation on the Reverse Martensitic Transformation of TiNi Shape Memory Alloy 被引量:14
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作者 Yanjun ZHENG Lishan CUI +1 位作者 Fan ZHANG Dazhi YANG 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2000年第6期611-614,共4页
DSC was used to study the effects of predeformation on the reverse martensitic transformation of near-equiatomic TiNi alloy. Both the start temperature As and the finish temperature Af of the reverse transformation in... DSC was used to study the effects of predeformation on the reverse martensitic transformation of near-equiatomic TiNi alloy. Both the start temperature As and the finish temperature Af of the reverse transformation increased with increasing degree of predeformation, but the algebraic difference between As and Af decreased with increasing predeformation until it reached a minimum value, then remained unchanged with further deformation. Transformation heat also increased with increasing predeformation until it reached a maximum value, then decreased with further predeformation. All the phenomena above were considered to be closely related with the release of elastic strain energy during predeformation. 展开更多
关键词 TINI effects of Predeformation on the Reverse Martensitic Transformation of TiNi Shape memory Alloy
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Effects of aging on the microstructure of a Cu-Al-Ni-Mn shape memory alloy 被引量:1
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作者 U.Sari T.Kirindi +1 位作者 F.Ozcan M.Dikici 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2011年第4期430-436,共7页
The influence of aging on the microstructure and mechanical properties of Cu-11.6wt%Al-3.9wt%Ni-2.5wt%Mn shape memory alloy(SMA) was studied by means of scanning electron microscopy(SEM),transmission electron micr... The influence of aging on the microstructure and mechanical properties of Cu-11.6wt%Al-3.9wt%Ni-2.5wt%Mn shape memory alloy(SMA) was studied by means of scanning electron microscopy(SEM),transmission electron microscopy(TEM),X-ray diffractometer,and differential scanning calorimeter(DSC).Experimental results show that bainite,γ2,and α phase precipitates occur with the aging effect in the alloy.After aging at 300°C,the bainitic precipitates appear at the early stages of aging,while the precipitates of γ2 phase are observed for a longer aging time.When the aging temperature increases,the bainite gradually evolves into γ2 phase and equilibrium α phase(bcc) precipitates from the remaining parent phase.Thus,the bainite,γ2,and α phases appear,while the martensite phase disappears progressively in the alloy.The bainitic precipitates decrease the reverse transformation temperature while the γ2 phase precipitates increase these temperatures with a decrease of solute content in the retained parent phase.On the other hand,these precipitations cause an increasing in hardness of the alloy. 展开更多
关键词 copper alloys shape memory effect martensitic transformations AGING PRECIPITATES
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Microwave sintering effects on the microstructure and mechanical properties of Ti–51at%Ni shape memory alloys 被引量:1
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作者 Mustafa K. Ibrahim E. Hamzah +2 位作者 Safaa N. Saud E. N. E. Abu Bakar A. Bahador 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2017年第3期280-288,共9页
Ti–51at%Ni shape memory alloys(SMAs) were successfully produced via a powder metallurgy and microwave sintering technique.The influence of sintering parameters on porosity reduction,microstructure,phase transformatio... Ti–51at%Ni shape memory alloys(SMAs) were successfully produced via a powder metallurgy and microwave sintering technique.The influence of sintering parameters on porosity reduction,microstructure,phase transformation temperatures,and mechanical properties were investigated by optical microscopy,field-emission scanning electron microscopy(FE-SEM),X-ray diffraction(XRD),differential scanning calorimetry(DSC),compression tests,and microhardness tests.Varying the microwave temperature and holding time was found to strongly affect the density of porosity,presence of precipitates,transformation temperatures,and mechanical properties.The lowest density and smallest pore size were observed in the Ti–51at%Ni samples sintered at 900°C for 5 min or at 900°C for 30 min.The predominant martensite phases of β2 and β19′ were observed in the microstructure of Ti–51at%Ni,and their existence varied in accordance with the sintering temperature and the holding time.In the DSC thermograms,multi-transformation peaks were observed during heating,whereas a single peak was observed during cooling;these peaks correspond to the presence of the β2,R,and β19′ phases.The maximum strength and strain among the Ti–51at%Ni SMAs were 1376 MPa and 29%,respectively,for the sample sintered at 900°C for 30 min because of this sample's minimal porosity. 展开更多
关键词 TITANIUM nickel alloys shape memory effect POWDER METALLURGY (PM) microwave HEATING SINTERING microstructure mechanical properties
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Effects of Ta Addition on NiTi Shape Memory Alloys 被引量:3
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作者 Jianlu MA, Jiangnan LIU+, Zhengpin WANG and Fei XUE (Dept. of Materials Science & Engineering, Xi’an Institute of Technology, Xi’an 710032, China) Kuang-Hsi WU and Zhongjie PU (Department of Mechanical Engineering, Florida International University, USA) 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2000年第5期534-536,共3页
The effect of Ta addition on the martensitic transformation characteristics and the X-ray visibility on NiTi shape memory alloy have been studied in (Ni51Ti49)1-xTax system. It was found that the transformation temper... The effect of Ta addition on the martensitic transformation characteristics and the X-ray visibility on NiTi shape memory alloy have been studied in (Ni51Ti49)1-xTax system. It was found that the transformation temperatures of the Ni51Ti49 binary alloy increased drastically by an addition of 0~4 at. pet Ta, but only slightly when the concentration exceeded 4 at. pct; the addition of Ta greatly decreases the sensitivity of the martensitic transformations to the variation in the Ni-Ti ratio. The addition of Ta to the NiTi binary alloy can improve its X-ray visibility. 展开更多
关键词 NITI effects of Ta Addition on NiTi Shape memory Alloys TA
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The neuroprotective effects of the anti-diabetic drug linagliptin against Aβ-induced neurotoxicity 被引量:2
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作者 Chih-Li Lin Chien-Ning Huang 《Neural Regeneration Research》 SCIE CAS CSCD 2016年第2期236-237,共2页
Impaired insulin signaling in Alzheimer’s disease(AD)brains:The insulin signaling pathway is a fundamental physiological mechanism that presents in nearly all vertebrate cells.However,sometimes cells stop respondi... Impaired insulin signaling in Alzheimer’s disease(AD)brains:The insulin signaling pathway is a fundamental physiological mechanism that presents in nearly all vertebrate cells.However,sometimes cells stop responding properly to insulin stimulation.This condition is known as insulin resistance,which is a hallmark of two very common conditions,metabolic syndrome and type 2 diabetes(T2D). 展开更多
关键词 GLP induced neurotoxicity DPP The neuroprotective effects of the anti-diabetic drug linagliptin against A AMPK
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Effects of aging treatment on the microstructure and superelasticity of columnar-grained Cu71Al18Mn11 shape memory alloy 被引量:3
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作者 Ji-li Liu Hai-you Huang Jian-xin Xie 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2016年第10期1157-1166,共10页
The effect of aging treatment on the superelasticity and martensitic transformation critical stress in columnar-grained Cu_(71)Al_(18)Mn_(11) shape memory alloy(SMA) at the temperature ranging from 250°C ... The effect of aging treatment on the superelasticity and martensitic transformation critical stress in columnar-grained Cu_(71)Al_(18)Mn_(11) shape memory alloy(SMA) at the temperature ranging from 250°C to 400°C was investigated. The microstructure evolution during the aging treatment was characterized by optical microscopy, scanning electron microscopy, transmission electron microscopy, and X-ray diffraction. The results show that the plate-like bainite precipitates distribute homogeneously within austenitic grains and at grain boundaries. The volume fraction of bainite increases with the increase in aging temperature and aging time, which substantially improves the martensitic transformation critical stress of the alloy, whereas the bainite only slightly affects the superelasticity. This behavior is attributed to a coherent relationship between the bainite and the austenite, as well as to the bainite and the martensite exhibiting the same crystal structure. The variations of the martensitic transformation critical stress and the superelasticity of columnar-grained Cu_(71)Al_(18)Mn_(11) SMA with aging-temperature and aging time are described by the Austin-Rickett equation, where the activation energy of bainite precipitation is 77.2 kJ ·mol1. Finally, a columnar-grained Cu_(71)Al_(18)Mn_(11) SMA with both excellent superelasticity(5%-9%) and high martensitic transformation critical stress(443-677 MPa) is obtained through the application of the appropriate aging treatments. 展开更多
关键词 copper aluminum manganese alloys shape memory effect columnar grains aging bainite superelasticity
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Excellent effects and possible mechanisms of action of a new antibody–drug conjugate against EGFR-positive triple-negative breast cancer 被引量:2
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作者 Dan-Dan Zhou Wei-Qi Bai +4 位作者 Xiao-Tian Zhai Li-Ping Sun Yong-Su Zhen Zhuo-Rong Li Qing-Fang Miao 《Military Medical Research》 SCIE CAS CSCD 2022年第4期419-431,共13页
Background:Triple-negative breast cancer(TNBC)is the most aggressive subtype and occurs in approximately 15%–20%of diagnosed breast cancers.TNBC is characterized by its highly metastatic and recurrent features,as wel... Background:Triple-negative breast cancer(TNBC)is the most aggressive subtype and occurs in approximately 15%–20%of diagnosed breast cancers.TNBC is characterized by its highly metastatic and recurrent features,as well as a lack of specific targets and targeted therapeutics.Epidermal growth factor receptor(EGFR)is highly expressed in a variety of tumors,especially in TNBC.LR004-VC-MMAE is a new EGFR-targeting antibody–drug conjugate produced by our laboratory.This study aimed to evaluate its antitumor activities against EGFR-positive TNBC and further studied its possible mechanism of antitumor action.Methods:LR004-VC-MMAE was prepared by coupling a cytotoxic payload(MMAE)to an anti-EGFR antibody(LR004)via a linker,and the drug-to-antibody ratio(DAR)was analyzed by HIC-HPLC.The gene expression of EGFR in a series of breast cancer cell lines was assessed using a publicly available microarray dataset(GSE41313)and Western blotting.MDA-MB-468 and MDA-MB-231 cells were treated with LR004-VC-MMAE(0,0.0066,0.066,0.66,6.6 nmol/L),and the inhibitory effects of LR004-VC-MMAE on cell proliferation were examined by CCK-8 and colony formation.The migration and invasion capacity of MDA-MB-468 and MDA-MB-231 cells were tested at different LR004-VCMMAE concentrations(2.5 and 5 nmol/L)with wound healing and Transwell invasion assays.Flow cytometric analysis and tumorsphere-forming assays were used to detect the killing effects of LR004-VC-MMAE on cancer stem cells(MDA-MB-468 and MDA-MB-231 cells).The mouse xenograft models were also used to evaluate the antitumor efficacy of LR004-VC-MMAE in vivo.Briefly,BALB/c nude mice were subcutaneously inoculated with MDA-MB-468 or MDAMB-231 cells.Then they were randomly divided into 4 groups(n=6 per group)and treated with PBS,naked LR004(10 mg/kg),LR004-VC-MMAE(10 mg/kg),or doxorubicin,respectively.Tumor sizes and the body weights of mice were measured every 4 d.The effects of LR004-VC-MMAE on apoptosis and cell cycle distribution were analyzed by flow cytometry.Western blotting was used to detect the effects of LR004-VC-MMAE on EGFR,ERK,MEK phosphorylation and tumor stemness marker gene expression.Results:LR004-VC-MMAE with a DAR of 4.02 were obtained.The expression of EGFR was found to be significantly higher in TNBC cells compared with non-TNBC cells(P<0.01).LR004-VC-MMAE inhibited the proliferation of EGFRpositive TNBC cells,and the ICvalues of MDA-MB-468 and MDA-MB-231 cells treated with LR004-VC-MMAE for 72 h were(0.13±0.02)nmol/L and(0.66±0.06)nmol/L,respectively,which were significantly lower than that of cells treated with MMAE[(3.20±0.60)nmol/L,P<0.01,and(6.60±0.50)nmol/L,P<0.001].LR004-VC-MMAE effectively inhibited migration and invasion of MDA-MB-468 and MDA-MB-231 cells.Moreover,LR004-VC-MMAE also killed tumor stem cells in EGFR-positive TNBC cells and impaired their tumorsphere-forming ability.In TNBC xenograft models,LR004-VC-MMAE at 10 mg/kg significantly suppressed tumor growth and achieved complete tumor regression on day 36.Surprisingly,tumor recurrence was not observed until the end of the experiment on day 52.In a mechanistic study,we found that LR004-VC-MMAE significantly induced cell apoptosis and cell cycle arrest at G/M phase in MDAMB-468[(34±5)%vs.(12±2)%,P<0.001]and MDA-MB-231[(27±4)%vs.(18±3)%,P<0.01]cells.LR004-VC-MMAE also inhibited the activation of EGFR signaling and the expression of cancer stemness marker genes such as Oct4,Sox2,KLF4 and EpCAM.Conclusions:LR004-VC-MMAE showed effective antitumor activity by inhibiting the activation of EGFR signaling and the expression of cancer stemness marker genes.It might be a promising therapeutic candidate and provides a potential therapeutic avenue for the treatment of EGFR-positive TNBC. 展开更多
关键词 Triple-negative breast cancer Epidermal growth factor receptor Antibody–drug conjugate Targeted therapy Antitumor effect
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Pruned Volterra Models with Memory Effects for Nonlinear Power Amplifiers 被引量:1
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作者 Pengpeng Li Qingfang Zhang +2 位作者 Ping Wang Zhongshan Xie Bing Liu 《Communications and Network》 2013年第3期570-572,共3页
In this letter, a novel model is proposed for modeling the nonlinearity and memory effects of power amplifiers. The classical Volterra model is modified through a function of the sum of nonlinearity order with sum of ... In this letter, a novel model is proposed for modeling the nonlinearity and memory effects of power amplifiers. The classical Volterra model is modified through a function of the sum of nonlinearity order with sum of memory length. The parameters of this model can be extracted in digital domain since the model is analyzed based on the envelope signals. The model we proposed enables a substantial reduction in the number of coefficients involved, and with excellent accuracy. 展开更多
关键词 VOLTERRA SERIES Power AMPLIFIER (PA) BEHAVIORAL Model memory effect
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New finite strain elastoplastic equations for accurately and explicitly simulating pseudoelastic-to-plastic transition effects of shape memory alloys 被引量:1
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作者 Siyu WANG Lin ZHAN +1 位作者 Huifeng XI Heng XIAO 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2020年第10期1583-1596,共14页
A new finite strain elatoplastic J2-flow model with coupling effects of both isotropic and anisotropic hardening is proposed with the co-rotational logarithmic rate.In terms of certain single-variable shape functions ... A new finite strain elatoplastic J2-flow model with coupling effects of both isotropic and anisotropic hardening is proposed with the co-rotational logarithmic rate.In terms of certain single-variable shape functions representing uniaxial loading and unloading curves,explicit multi-axial expressions for the three hardening quantities incorporated in the new model proposed are derived in unified forms for the purpose of automatically and accurately simulating complex pseudoelastic-to-plastic transition effects of shape memory alloys(SMAs)under multiple loading-unloading cycles.Numerical examples show that with only a single parameter of direct physical meaning for each cycle,accurate and explicit simulations may be achieved for extensive data from multiple cycle tests. 展开更多
关键词 shape memory alloy(SMA) finite deformation PSEUDO-ELASTICITY plasticity cyclic loading transition effect elastoplastic equation explicit and accurate approach
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Wavelet network based predistortion method for wideband RF power amplifiers exhibiting memory effects 被引量:1
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作者 JIN Zhe SONG Zhi-huan HE Jia-ming 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2007年第4期625-630,共6页
RF power amplifiers (PAs) are usually considered as memoryless devices in most existing predistortion techniques. Nevertheless, in wideband communication systems, PA memory effects can no longer be ignored and memoryl... RF power amplifiers (PAs) are usually considered as memoryless devices in most existing predistortion techniques. Nevertheless, in wideband communication systems, PA memory effects can no longer be ignored and memoryless predistortion cannot linearize PAs effectively. After analyzing PA memory effects, a novel predistortion method based on wavelet networks (WNs) is proposed to linearize wideband RF power amplifiers. A complex wavelet network with tapped delay lines is applied to construct the predistorter and then a complex backpropagation algorithm is developed to train the predistorter parameters. The simulation results show that compared with the previously published feed-forward neural network predistortion method, the proposed method provides faster convergence rate and better performance in reducing out-of-band spectral regrowth. 展开更多
关键词 Power amplifiers. Predistortion. memory effects. Wavelet networks
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Effects of ginsenoside of stem and leaf combined with choline on learning and memory ability of rat models with Alzheimer diseases 被引量:1
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作者 Xiaomin Zhao Xianglin Xie +3 位作者 Zuoli Xia Yunsheng Gao Yuyun Zhu Hongxia Gu 《Neural Regeneration Research》 SCIE CAS CSCD 2006年第4期331-334,共4页
BACKGROUND: Central adrenergic nerve and 5-serotonergic nerve can influence central cholinergic nerve on learning and memory and make easy for study; however, ginsenoside of stem and leaf (GSL) can improve function... BACKGROUND: Central adrenergic nerve and 5-serotonergic nerve can influence central cholinergic nerve on learning and memory and make easy for study; however, ginsenoside of stem and leaf (GSL) can improve functions of central adrenergic nerve; moreover, 5-serotonergic nerve and the combination with choline can produce synergistic effect and enhance learning and memory ability so as to improve learning and memory disorder of patients with Alzheimer disease (AD). OBJECTIVE : To observe the effects of GSL combining with choline on learning and memory of AD model rats DESIGN : Randomized grouping design and controlled animal study SETIING : Department of Pharmacology, Taishan Medical College MATERIALS : The experiment was carried out in the Pharmacological Department of Medical College of Jilin University from October 1996 to January 1997. Forty healthy male Wistar rats of clean grade were randomly divided into 5 groups, including sham-injury group, model group, GSL group, choline group and combination group, with 8 rats in each group. Main medications: GSL with the volume more than 92.8% was provided by Department of Chemistry, Norman Bethune Medical College of Jilin University. Panaxatriol, the main component, was detected with thin layer scanning technique and regarded as the index of GSL quality [(55±1)%, CV= 2%, n = 5]. Choline was provided by the Third Shanghai Laboratory Factory. METHODS : 150 nmol quinolinic acid was used to damage bilateral Meynert basal nuclei of adult rats so as to establish AD models. Rats in GSL, choline and combination groups were intragastric administrated with 400 mg/kg GSL, 200 mg/kg choline (20 mL/kg), and both respectively last for 17 days starting from two days before operation. Rats in sham-injury group and model group were perfused with the same volume of distilled water once in each morning for the same days. (1) Passive avoidance step-down test: Five minutes later, rats jumped up safe platform when they were shocked with 36 V alternating current. If rats jumped down from the platform and the feet touched railings, the response was wrong. Numbers of wrong response were recorded within 3 minutes, and then the test was redone after 24 hours. (2) Morris water-maze spatial localization task: Swimming from jumping-off to platform directly was regarded as right response. Additionally, 4 successively right responses were regarded as the standard. Each rat was trained 10 times a day with 120 s per time for 3 successive days. The interval was 30 s. Three days later, numbers of right response were recorded. The training times were increased to 30 for unlearned rats. (3) Measurement of activity of choline acetylase in cerebral cortex: Rats were sacrificed at 17 days after operation to obtain cerebral cortex to measure activity of choline acetylase with radiochemistry technique. (4) Synergistic effect: It was expressed as Q value: Q value = factual incorporative effect/anticipant incorporative effect; Q ≥ 1 was regarded as synergistic effect. Anticipant incorporative effect = (EA+EB-EA·EB), EA and EB were single timing effect, respectively in GSL group and choline group. E(step-down test and Morris water maze test) = (x in model group - factual value in medicine groups)/x in model group; E (activity of choline acetylase) = (factual value in medicine groups -xin model group)/xin model group. MAIN OUTCOME MEASURES : (1) Passive avoidance step-down test and Morris water-maze spatial localization task in the study of learning and memory; (2) activity of choline acetylase. RESULTS : All 40 rats were involved in the final analysis. (1) Passive avoidance response: At learning phase on first day and retesting phase on the next day, numbers of wrong responses within 3 minutes were more in model group than sham operation group, and there was significant difference [(5.88±1.46), (2.25±0.87) times; (2.63±1.06), (0.50±0.53) times; P 〈 0.01]; numbers of wrong responses within 3 minutes were less in combination group than model group, and there was significant difference [learning phase: (1.12±0.83), (5.88±1.46) times; retesting phase: (0.38±0.74), (2.63±1.06)times, P 〈 0.01]; moreover, effect was stronger than that in GSL group and choline group. The Q value was 1.07 and 1.59, respectively and it showed synergistic effect. Spatial localization task: Training times were more in model group than sham operation group, and there was significant difference [(2.9±2.5), (12.6±3.5) times; P 〈 0.01]. Training times were less in combination group than model group, and there was significant difference [(11.8±2.4), (27.9±2.5) times, P 〈 0.01]; moreover, effect was stronger than that in GSL group and choline group. The Q value was 1.07 and it showed synergistic effect. (3) Activity of choline acetylase: Activity was lower in model group than sham operation group, and there was significant difference [(30.56±8.33), (61.11 ±8.33) nkat/g; P 〈 0.01]. Activity was higher in combination group than model group and there was significant difference [(50.00±8.33), (30.56±8.33) nkat/g, P 〈 0.01];moreover, effect was stronger than that in GSL group and choline group. The Q value was 1.5 and it showed synergistic effect. CONCLUSZON: GSL in combination with choline can synergically improve the disorder of learning and memory of AD model rats. Its mechanism may be involved in enhancing the function of central cholinergic system. 展开更多
关键词 stem effects of ginsenoside of stem and leaf combined with choline on learning and memory ability of rat models with Alzheimer diseases
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Total Ionization Dose Effects on Charge Storage Capability of Al2O3/HfO2/Al2O3-Based Charge Trapping Memory Cell 被引量:1
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作者 Yan-Nan Xu Jin-Shun Bi +5 位作者 Gao-Bo Xu Bo Li Kai Xi Ming Liu Hai-Bin Wang Li Luo 《Chinese Physics Letters》 SCIE CAS CSCD 2018年第11期86-89,共4页
Because of the discrete charge storage mechanism, charge trapping memory(CTM) technique is a good candidate for aerospace and military missions. The total ionization dose(TID) effects on CTM cells with Al2O3/HfO2/... Because of the discrete charge storage mechanism, charge trapping memory(CTM) technique is a good candidate for aerospace and military missions. The total ionization dose(TID) effects on CTM cells with Al2O3/HfO2/Al2O3(AHA) high-k gate stack structure under in-situ 10 keV x-rays are studied. The C-V characteristics at different radiation doses demonstrate that charge stored in the device continues to be leaked away during the irradiation,thereby inducing the shift of flat band voltage(V(fb)). The dc memory window shows insignificant changes, suggesting the existence of good P/E ability. Furthermore, the physical mechanisms of TID induced radiation damages in AHA-based CTM are analyzed. 展开更多
关键词 AHA Total Ionization Dose effects on Charge Storage Capability of Al2O3/HfO2/Al2O3-Based Charge Trapping memory Cell Al
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Why Don’t We Adequately Identify and Manage Adverse Drug Reactions despite Having the Needed Information?
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作者 Mark J. Kupersmith Karl Kieburtz 《Health》 2024年第2期148-159,共12页
Importance/Objective: Adverse Drug Reactions (ADRs) are unavoidable, but recognizing and addressing ADRs early can improve wellness and prevent permanent injury. We suggest that available medical information and digit... Importance/Objective: Adverse Drug Reactions (ADRs) are unavoidable, but recognizing and addressing ADRs early can improve wellness and prevent permanent injury. We suggest that available medical information and digital/electronic methods could be used to manage this major healthcare problem for individual patients in real time. Methods: We searched the available digital applications and three literature databases using the medical subject heading terms, adverse drug reaction reporting systems or management, filtered by clinical trial or systemic reviews, to detect publications with data about ADR identification and management approaches. We reviewed the reports that had abstract or summary data or proposed or implemented methods or systems with potential to identify or manage ADRs in clinical settings. Results: The vast majority of the 481 reports used retrospectively collected data for groups of patients or were limited to surveying one population group or class of medication. The reports showed potential and definite associations of ADRs for specific drugs and problems, mostly, but not exclusively, for patients in hospitals and nursing homes. No reports described complete methods to collect comprehensive data on ADRs for individual patients in a healthcare system. The digital applications have ADR information, but all are too cumbersome or incomplete for use in active clinical settings. Several studies suggested that providing information about potential ADRs to clinicians can reduce these problems. Conclusion and Relevance: Although investigators and government agencies agree with the need, there is no comprehensive ADR management program in current use. Informing the patient’s healthcare practitioners of potential ADRs at the point of service has the potential for reduction of these complications, which should improve healthcare and reduce unneeded costs. 展开更多
关键词 Adverse drug Reaction Medication Side effect Identification Medication Complication Medication Safety
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Effect of Ultrasound-Guided Transversus Abdominis Plane Block Combined with Lornoxicam on Pain and Recovery Quality After Abdominal Surgery in Patients with Drug Addiction
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作者 Ling Luo Zhouxu Yang Hongtao Yang 《Journal of Clinical and Nursing Research》 2023年第5期89-96,共8页
Objective:This paper aims to analyze the analgesic effect of ultrasound-guided transversus abdominis plane block(TAPB)combined with non-steroidal anti-inflammatory analgesic drug lornoxicam on abdominal surgery in pat... Objective:This paper aims to analyze the analgesic effect of ultrasound-guided transversus abdominis plane block(TAPB)combined with non-steroidal anti-inflammatory analgesic drug lornoxicam on abdominal surgery in patients with a history of drug addiction.Methods:32 patients aged 18-60 who underwent lower abdominal surgery in the First People's Hospital of Liangshan Yi Autonomous Prefecture and Butuo County People's Hospital of Liangshan Yi Autonomous Prefecture from January 2022 to March 2023 were selected,the patients must have drug abuse history for more than 1 year,with a history of drug withdrawal and relapse.The patients were divided into observation group and control group by the envelope method,with 16 cases in the observation group and 16 cases in the control group.Two groups of patients underwent ultrasound-guided bilateral transversus abdominis plane block after the operation.The observation group was treated with dexmedetomidine hydrochloride 1μg/kg+0.25%ropivacaine hydrochloride 40ml,and the control group was treated with 40ml 0.9%sodium chloride injection,the two groups of patients returned to the ward after operation and given intravenous infusion of lornoxicam for relieving the pain.The visual analogue scale(VAS)score of postoperative pain,the times of rescue analgesia,the time of postoperative anal exhaust,the time of ambulation,nausea and vomiting,withdrawal symptoms,related adverse reactions,and hospitalization days were compared between the two groups.Results:The VAS score of postoperative pain in the observation group was significantly lower than that in the control group,P<0.05.Patients in the observation group used less postoperative rescue analgesics than those in the control group,P<0.05.For postoperative anal exhaust time,the difference between the two groups of patients was relatively small,and the time in the observation group was shorter,P>0.05.The time to get out of bed and the length of hospital stay were not significantly different between the control group and the observation group,P>0.05.The withdrawal symptoms of the patients in the observation group were better,P<0.05,nausea and vomiting,and other adverse reactions were lower in the control group,P<0.05.Conclusion:Ultrasound-guided transversus abdominis plane block combined with lornoxicam can be used to relieve pain in abdominal surgery for patients with drug addiction,which can effectively improve the therapeutic effect of patients and reduce the number of postoperative rescue analgesia.Thus,it has high clinical application value. 展开更多
关键词 Ultrasound-guided transversus abdominis plane block LORNOXICAM Patients with drug addiction Nursing effect
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Volterra series based predistortion for broadband RF power amplifiers with memory effects
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作者 Jin Zhe Song Zhihuan He Jiaming 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2008年第4期666-671,共6页
RF power amplifiers (PAs) are usually considered as memoryless devices in most existing predistortion techniques. However, in broadband communication systems, such as WCDMA, the PA memory effects are significant, an... RF power amplifiers (PAs) are usually considered as memoryless devices in most existing predistortion techniques. However, in broadband communication systems, such as WCDMA, the PA memory effects are significant, and memoryless predistortion cannot linearize the PAs effectively. After analyzing the PA memory effects, a novel predistortion method based on the simplified Volterra series is proposed to linearize broadband RF PAs with memory effects. The indirect learning architecture is adopted to design the predistortion scheme and the reeursive least squares algorithm with forgetting factor is applied to identify the parameters of the predistorter. Simulation results show that the proposed predistortion method can compensate the nonlinear distortion and memory effects of broadband RF PAs effectively. 展开更多
关键词 power amplifiers PREDISTORTION memory effects Volterra series
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