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Piezoelectric and flexoelectric effects of DNA adsorbed films on microcantilevers
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作者 Yuan YANG Nenghui ZHANG +2 位作者 Hanlin LIU Jiawei LING Zouqing TAN 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2023年第9期1547-1562,共16页
DNA-based biosensors have played a huge role in many areas,especially in current global coronavirus outbreak.However,there is a great difficulty in the characterization of piezoelectric and flexoelectric coefficients ... DNA-based biosensors have played a huge role in many areas,especially in current global coronavirus outbreak.However,there is a great difficulty in the characterization of piezoelectric and flexoelectric coefficients of the nanoscale DNA film,because the existing experimental methods for hard materials are almost invalid.In addition,the relevant theoretical models for DNA films only consider a single effect without clarifying the difference between the two electromechanical effects on device detection signals.This work aims to present multiscale models for DNA-microcantilever experiments to clarify the competitive mechanism in piezoelectric and flexoelectric effects of DNA films on detection signals.First,a Poisson-Boltzmann(PB)equation is used to predict the potential distribution due to the competition between fixed phosphate groups and mobile salt ions in DNA films.Second,a macroscopic piezoelectric/flexoelectric constitutive equation of the DNA film and a mesoscopic free energy model of the DNA solution are combined to analytically predict the electromechanical coefficients of the DNA film and the relevant microcantilever signals by the deformation equivalent method and Zhang’s two-variable method.Finally,the effects of detection conditions on microscopic interactions,electromechanical coupling coefficients,and deflection signals are studied.Numerical results not only agree well with the experimental observations,but also reveal that the piezoelectric and flexoelectric effects of the DNA film should be equivalently modeled when interpreting microcantilever detection signals.These insights might provide opportunities for the microcantilever biosensor with high sensitivity. 展开更多
关键词 dna microcantilever biosensor electromechanical coupling effect flexo-electricity PIEZOELECTRICITY multiscale model
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氧化石墨烯-DNA纳米探针用于三磷酸腺苷的检测与药物递送
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作者 张越 梁蕊 +1 位作者 赵灿男 李春梅 《应用化学》 CAS CSCD 北大核心 2024年第1期118-127,共10页
癌细胞内三磷酸腺苷(ATP)浓度异常与肿瘤发生发展过程密切相关,因此,快速、准确地检测细胞内外ATP水平具有重要意义。盐酸阿霉素(DOX)是一种广泛使用的抗癌药物,能嵌入DNA碱基对,并通过抑制DNA复制和转录诱导细胞凋亡。氧化石墨烯(Graph... 癌细胞内三磷酸腺苷(ATP)浓度异常与肿瘤发生发展过程密切相关,因此,快速、准确地检测细胞内外ATP水平具有重要意义。盐酸阿霉素(DOX)是一种广泛使用的抗癌药物,能嵌入DNA碱基对,并通过抑制DNA复制和转录诱导细胞凋亡。氧化石墨烯(Graphene oxide, GO)由于具有毒性低、比表面积大和易功能化,可以有效、稳定地负载DNA纳米探针进入细胞等优点而被广泛应用。然而,复杂环境中的生物分子容易通过物理吸附竞争性结合到GO表面,导致假阳性信号。基于此,提出了一种新型的GO-DNA纳米探针,并将其应用于ATP的检测与抗癌药物DOX靶向递送。以ATP的核酸适配体与其互补链杂交形成双链DNA(dsDNA),并通过G-C碱基对负载DOX,利用互补链延伸的poly A序列吸附到GO表面构建了GO-dsDNA-DOX纳米探针,能极大程度地降低复杂环境中物理吸附引起的干扰,减少假阳性信号产生。ATP与适配体特异性结合会导致DOX释放,根据其荧光“off-on”实现ATP的定量分析,DOX荧光强度与ATP含量在0.08~8.0 mmol/L范围内呈现良好的线性关系,线性方程为IF=3.0897c+129.08,检测限(3σ/k)为0.059 mmol/L,且方法具有良好的选择性和抗干扰能力。细胞毒性及荧光成像结果表明,负载DOX的纳米探针在人乳腺癌细胞(MCF-7)内有明显的药物释放,显著诱导细胞凋亡。该研究建立了一种免修饰、简单和快速的ATP含量检测分析方法,并利用癌细胞内高浓度ATP实现靶向药物递送,降低了对正常细胞的毒副作用,为癌症的治疗提供了新思路。 展开更多
关键词 三磷酸腺苷 dna纳米探针 氧化石墨烯 荧光检测 盐酸阿霉素 药物递送
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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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A robust luminescent assay for screening alkyladenine DNA glycosylase inhibitors to overcome DNA repair and temozolomide drug resistance
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作者 Ying-Qi Song Guo-Dong Li +5 位作者 Dou Niu Feng Chen Shaozhen Jing Vincent Kam Wai Wong Wanhe Wang Chung-Hang Leung 《Journal of Pharmaceutical Analysis》 SCIE CAS CSCD 2023年第5期514-522,共9页
Temozolomide(TMZ)is an anticancer agent used to treat glioblastoma,typically following radiation therapy and/or surgical resection.However,despite its effectiveness,at least 50%of patients do not respond to TMZ,which ... Temozolomide(TMZ)is an anticancer agent used to treat glioblastoma,typically following radiation therapy and/or surgical resection.However,despite its effectiveness,at least 50%of patients do not respond to TMZ,which is associated with repair and/or tolerance of TMZ-induced DNA lesions.Studies have demonstrated that alkyladenine DNA glycosylase(AAG),an enzyme that triggers the base excision repair(BER)pathway by excising TMZ-induced N3-methyladenine(3meA)and N7-methylguanine lesions,is overexpressed in glioblastoma tissues compared to normal tissues.Therefore,it is essential to develop a rapid and efficient screening method for AAG inhibitors to overcome TMZ resistance in glioblastomas.Herein,we report a robust time-resolved photoluminescence platform for identifying AAG inhibitors with improved sensitivity compared to conventional steady-state spectroscopic methods.As a proof-of-concept,this assay was used to screen 1440 food and drug administration-approved drugs against AAG,resulting in the repurposing of sunitinib as a potential AAG inhibitor.Sunitinib restored glioblastoma(GBM)cancer cell sensitivity to TMZ,inhibited GBM cell proliferation and stem cell characteristics,and induced GBM cell cycle arrest.Overall,this strategy offers a new method for the rapid identification of small-molecule inhibitors of BER enzyme activities that can prevent false negatives due to a fluorescent background. 展开更多
关键词 drug screening Alkyladenine dna glycosylase N3-methyladenine GLIOBLASTOMA TEMOZOLOMIDE SUNITINIB
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DNADam ageEffectsofHydroxyapatiteUltrofinePowderonW-256 Sarcom a Cells and Lym phocytes in Rats 被引量:1
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作者 XIA Qinghua 1, HU Panlin 2, CHEN Daoda 1, ZHANG Jianpin 1, TIAN Yuan 1, ZHANG Jinghui 1 1 Department of General Surgery, Xiehe Hospital, Tongji Medical University, Wuhan 430022 2 Departmnet of General Surgery, Puqi Peoples Hospital, 《Journal of Huazhong University of Science and Technology(Medical Sciences)》 SCIE CAS 1999年第3期215-218,共4页
To explore the anticancer mechanism and DNA damages of hydroxyapatite ultrofine powder (HAUFP) on lymphocytes of rats, DNA damages in W 256 sarcoma cells and lymphocytes of rats were measured by single cell gel elec... To explore the anticancer mechanism and DNA damages of hydroxyapatite ultrofine powder (HAUFP) on lymphocytes of rats, DNA damages in W 256 sarcoma cells and lymphocytes of rats were measured by single cell gel electrophoresis (SCGE). The results showed that HAUFP damaged DNA of W 256 sarcoma cells obviously but only cause slight damage of DNA of lymphocytes in rats. It is suggested that HAUFP selectively damaged DNA of tumor cells with only mild damage of lymphocyte DNA. HAUFP has powerful anticancer effect and little genetic toxicity. 展开更多
关键词 hydroxyapatite ultrofine powder dna damage anticancer effect RATS
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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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铜绿假单胞菌oprI基因DNA疫苗及其重组亚单位疫苗免疫效果的评估
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作者 祝世纪 宫强 +1 位作者 田佳雨 李雅静 《中国预防兽医学报》 CAS CSCD 北大核心 2024年第3期285-291,共7页
为评估铜绿假单胞菌opr I基因DNA疫苗和重组亚单位疫苗对小鼠的免疫效果,本实验将铜绿假单胞菌外膜蛋白编码基因opr I克隆至真核表达载体p CAGGS-HA中构建重组质粒p CAGGS-opr I,经酶切鉴定正确后获得DNA疫苗。同时将opr I基因克隆至原... 为评估铜绿假单胞菌opr I基因DNA疫苗和重组亚单位疫苗对小鼠的免疫效果,本实验将铜绿假单胞菌外膜蛋白编码基因opr I克隆至真核表达载体p CAGGS-HA中构建重组质粒p CAGGS-opr I,经酶切鉴定正确后获得DNA疫苗。同时将opr I基因克隆至原核表达载体p ET32a中构建重组质粒p ET32a-oprI,经酶切鉴定正确后转入大肠杆菌,经IPTG诱导重组Opr I蛋白(rOprI)的表达,采用亲和层析法纯化后以SDS-PAGE检测,结果显示正确表达了r Opr I,且获得了其纯化蛋白,利用其制备重组亚单位疫苗。分别以DNA疫苗和重组亚单位疫苗免疫BALB/c小鼠,并以铜绿假单胞菌的灭活疫苗和外膜蛋白疫苗为对照,采用间接ELISA法检测免疫后不同时间小鼠血清中的抗体水平和血清中IFN-γ、IL-2和IL-4的含量;初免42 d后以铜绿假单胞菌(1.25×109 cfu/mL,100μL/只)对各组小鼠进行攻毒试验,通过测定各疫苗对小鼠的保护率,评估疫苗的保护效果。结果显示,各疫苗诱导的免疫小鼠血清抗体水平和细胞因子含量均显著高于阴性对照组(P<0.05),且重组亚单位疫苗诱导小鼠的抗体水平和IL-4含量均显著高于DNA疫苗(P<0.05),而IFN-γ和IL-2含量则与DNA疫苗无显著差异(P>0.05)。小鼠攻毒试验结果显示,DNA疫苗组、重组亚单位疫苗组、外膜蛋白疫苗组和灭活疫苗组小鼠获得的免疫保护率分别为45%、55%、70%和95%。上述结果首次表明以铜绿假单胞菌opr I基因制备的DNA疫苗和r Opr I重组亚单位疫苗均可诱导小鼠产生体液和细胞免疫应答,并可为小鼠提供对铜绿假单胞菌攻毒的免疫保护效果,但二者的免疫效果还需进一步提高。本研究为铜绿假单胞菌疫苗的研究提供了参考依据。 展开更多
关键词 铜绿假单胞菌 oprI基因 dna疫苗 重组亚单位疫苗 免疫效果
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外周血循环肿瘤DNA预测晚期非小细胞肺癌免疫治疗疗效及预后价值
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作者 袁胜芳 王布 +3 位作者 项保利 赵建清 沈晶晶 张志华 《实用医学杂志》 CAS 北大核心 2024年第15期2110-2115,共6页
目的探讨外周血循环肿瘤DNA预测晚期非小细胞肺癌(NSCLC)免疫治疗疗效及预后的价值。方法对2021年1-12月收治于河北北方学院附属第一医院呼吸与危重症医学科住院的78例晚期驱动基因阴性使用替雷利珠单抗治疗的NSCLC患者进行前瞻性研究,... 目的探讨外周血循环肿瘤DNA预测晚期非小细胞肺癌(NSCLC)免疫治疗疗效及预后的价值。方法对2021年1-12月收治于河北北方学院附属第一医院呼吸与危重症医学科住院的78例晚期驱动基因阴性使用替雷利珠单抗治疗的NSCLC患者进行前瞻性研究,免疫治疗2周期后按照实体瘤疗效评价标准(RECIST1.1)评价疗效,包括完全缓解(CR)、部分缓解(PR)、疾病稳定及疾病进展,将CR和PR患者定义为观察组(n=48),其他患者被定义为对照组(n=30),测定两组患者治疗前后外周血中ctDNA水平,采用ROC曲线分析外周血ctDNA水平对于免疫治疗后达客观缓解的预测价值。对所有患者进行随访,统计其无进展生存期,采用单因素及多因素回归分析免疫治疗后患者预后的影响因素,采用Spearman相关系数对ctDNA水平与PFS进行相关性分析,采用Kalplan-Meier生存曲线进行生存分析。结果观察组治疗前后外周血ctDNA水平分别为(4.47±1.21)、(2.65±1.14)ng/μL(t=7.559,P<0.001),对照组治疗前后外周血ctDNA水平为(4.54±1.15)、(4.29±1.57)ng/μL(t=0.699,P=0.487),两组患者在治疗前外周血ctDNA水平差异无统计学意义(t=-0.25,P=0.801),观察组治疗后外周血ctDNA水平较对照组下降(t=-5.35,P<0.001)。ROC曲线分析外周血ctDNA水平预测免疫治疗后达客观缓解的曲线下面积为0.819,预测的敏感性度81.3%,特异度为80%,外周血ctDNA水平与患者无进展生存期(PFS)呈负相关(r=-0.784,P<0.001),采用单因素Cox回归对入组患者的临床病理特征及ctDNA水平进行分析,结果显示肿瘤最大径>5 cm(HR=0.501,95%CI:0.282~0.890)、肿瘤Ⅳ期(HR=0.392,95%CI:0.227~0.677)、治疗方式(HR=15.473,95%CI:6.731~35.567)及ctDNA水平(HR=4.567,95%CI:3.182~6.555)均为晚期NSCLC患者免疫治疗后PFS的影响因素,再将有统计学差异的上述指标进行多因素分析,结果显示:治疗方式(HR=2.981,95%CI:1.019~8.722)及外周血ctDNA水平(HR=3.918,95%CI:2.619~5.861)是晚期NSCLC患者PFS的独立影响因素,采用Kalplan-Meier生存曲线进行分析,结果显示观察组的中位PFS为8.4个月,对照组的中位PFS为5.4个月,差异有统计学意义(χ^(2)=46.828,P=0.000)。结论免疫联合化疗可增强杀伤肿瘤细胞的能力,外周血ctDNA水平可评估免疫治疗的疗效及预后,可用于指导晚期NSCLC患者的免疫治疗。 展开更多
关键词 循环肿瘤dna 非小细胞肺癌 免疫检查点抑制剂 疗效分析 预后
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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:1
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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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基于环境DNA技术的黄河流域下游山区河流大型底栖动物群落多样性特征及其影响要素分析
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作者 赵茜 潘福霞 +2 位作者 李斌 臧小苗 丁森 《湖泊科学》 EI CAS CSCD 北大核心 2024年第2期523-535,共13页
河流生物群落组成由多种环境因子共同作用形成,但其影响机制尚不清楚。本研究基于环境DNA技术,选择黄河流域下游4条山区河流(锦绣川、锦阳川、锦云川和三川汇合后河流)的10个样点开展大型底栖动物监测。结果发现:不同溪段水质状况有所差... 河流生物群落组成由多种环境因子共同作用形成,但其影响机制尚不清楚。本研究基于环境DNA技术,选择黄河流域下游4条山区河流(锦绣川、锦阳川、锦云川和三川汇合后河流)的10个样点开展大型底栖动物监测。结果发现:不同溪段水质状况有所差异,锦云川盐化程度(以电导率EC表征)和营养盐浓度较高,锦阳川抗生素浓度较高,锦绣川水质较好。山区河流大型底栖动物群落组成差异明显,锦绣川以水生昆虫为主,软体动物占比较低。其中,昆虫纲的大蚊(Tipula abdominalis)、天角蜉(Uracanthella punctisetae)和寡毛纲的顠体虫(Aeolosoma sp.)是造成锦绣川与其他河流大型底栖动物群落结构差异的关键物种。冗余分析和变差分解分析结果表明,盐化、营养盐和抗生素均会对大型底栖动物群落组成产生影响。其中,EC的解释率为22.86%,营养盐中的TP、NH_(3)-N和TN的解释率分别为20.12%、13.25%和7.81%;此外,盐化可与营养盐和抗生素通过耦合效应对大型底栖动物群落组成产生影响,贡献率分别为21.60%和16.20%;抗生素与营养盐的贡献率为19.60%。逐步判别回归模型结果显示,Margalef指数(d)受盐化(EC)和营养盐(NH_(3)-N和NO_(3)^(-)-N)的共同影响;随着河流中EC浓度升高,d与NH_(3)-N之间的正响应关系及其与NO_(3)^(-)-N之间的负响应关系显著增强。因此,多环境因子对水生生物的影响不容忽视,在大型底栖动物生物多样性保护中应关注各类环境因子的影响贡献。 展开更多
关键词 环境dna 多环境因子 耦合效应 大型底栖动物 山区河流 黄河流域下游
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DNA损伤效应主动监测的抗氧化基因缺失微生物传感器的构建及性能评价
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作者 俞悦 李安一 +5 位作者 王文甲 姜浩 邓玉林 李晓琼 吕雪飞 戴荣继 《航天医学与医学工程》 CAS 2024年第2期73-77,共5页
目的活性氧基团(ROS)水平升高会引起生物体的DNA氧化损伤,监测DNA的氧化损伤程度,能够实现ROS损伤效应的有效评价。基于微生物传感器监测DNA损伤效应可以定量评价氧化损伤程度,但微生物本身具有的ROS清除机制,会影响监测灵敏度。本研究... 目的活性氧基团(ROS)水平升高会引起生物体的DNA氧化损伤,监测DNA的氧化损伤程度,能够实现ROS损伤效应的有效评价。基于微生物传感器监测DNA损伤效应可以定量评价氧化损伤程度,但微生物本身具有的ROS清除机制,会影响监测灵敏度。本研究旨在敲除细菌ROS清除机制的关键基因,构建抗氧化基因缺失微生物传感器,实现对DNA损伤效应的灵敏监测,评价ROS对生物体的损伤效应。方法本研究基于λ-Red同源重组的方法敲除细菌抗氧化损伤相关基因ahpCF、katE与katG,构建抗氧化基因缺失微生物传感器,并评价传感器对萘啶酮酸钠和紫外照射的响应。结果成功构建ΔahpCF、ΔahpCF/ΔkatE与ΔahpCF/ΔkatE/ΔkatG三种抗氧化基因缺失的微生物传感器,工程菌ΔahpCF/ΔkatE/ΔkatG对DNA损伤试剂萘啶酮酸钠的响应灵敏度最高,检测限为0.40μmol/L,另外,1.80 min的紫外照射(254 nm)可诱导工程菌产生显著的荧光表达效应。结论本研究构建了抗氧化基因缺失微生物传感器,实现了对DNA损伤试剂和紫外照射等DNA损伤效应的主动灵敏监测,可为未来空间辐射效应的评价提供一种主动、有效、灵敏的潜在监测方法。 展开更多
关键词 dna损伤效应 基因敲除 微生物传感器 空间辐射 萘啶酮酸钠 紫外照射
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Antibody-platinum(IV)prodrugs conjugates for targeted treatment of cutaneous squamous cell carcinoma
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作者 Xiangye Yin Yingjie Zhuang +9 位作者 Haiqin Song Yujian Xu Fan Zhang Jianxin Cui Lei Zhao Yingjie Yu Qixu Zhang Jun Ye Youbai Chen Yan Han 《Journal of Pharmaceutical Analysis》 SCIE CAS CSCD 2024年第3期389-400,共12页
Antibody-drug conjugates(ADCs)are a new type of targeting antibodies that conjugate with highly toxic anticancer drugs via chemical linkers to exert high specificity and efficient killing of tumor cells,thereby attrac... Antibody-drug conjugates(ADCs)are a new type of targeting antibodies that conjugate with highly toxic anticancer drugs via chemical linkers to exert high specificity and efficient killing of tumor cells,thereby attracting considerable attention in precise oncology therapy.Cetuximab(Cet)is a typical antibody that offers the benefits of good targeting and safety for individuals with advanced and inoperable cutaneous squamous cell carcinoma(cSCC);however,its anti-tumor activity is limited to a single use.Cisplatin(CisPt)shows good curative effects;however,its adverse effects and non-tumor-targeting ability are major drawbacks.In this study,we designed and developed a new ADC based on a new cytotoxic platinum(IV)prodrug(C8Pt(IV))and Cet.The so-called antibody-platinum(IV)prodrugs conjugates,named Cet-C8Pt(IV),showed excellent tumor targeting in cSCC.Specifically,it accurately delivered C8Pt(IV)into tumor cells to exert the combined anti-tumor effect of Cet and CisPt.Herein,metabolomic analysis showed that Cet-C8Pt(IV)promoted cellular apoptosis and increased DNA damage in cSCC cells by affecting the vitamin B6 metabolic pathway in tumor cells,thereby further enhancing the tumor-killing ability and providing a new strategy for clinical cancer treatment using antibody-platinum(IV)prodrugs conjugates. 展开更多
关键词 Antibody drug conjugate Cutaneous squamous cell carcinoma dna damage Platinum drug Targeted therapy
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ecDNA在小细胞肺癌致癌相关性、异质性和耐药性的机制研究进展
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作者 杜威 陆瑶 +1 位作者 陆亚兴(综述) 董秀娟(审校) 《中国肿瘤临床》 CAS CSCD 北大核心 2024年第4期203-208,共6页
随着染色体外DNA(extrachromosomal DNA,ecDNA)研究的深入,研究发现ecDNA大多只存在于肿瘤细胞内,并且在肿瘤异质性和耐药中起着关键作用。ecDNA存在于多种恶性肿瘤中,但在正常细胞中极少出现。因为ecDNA具有强大的癌基因扩增和动态改... 随着染色体外DNA(extrachromosomal DNA,ecDNA)研究的深入,研究发现ecDNA大多只存在于肿瘤细胞内,并且在肿瘤异质性和耐药中起着关键作用。ecDNA存在于多种恶性肿瘤中,但在正常细胞中极少出现。因为ecDNA具有强大的癌基因扩增和动态改变能力,故肿瘤细胞中含有ecDNA的患者临床预后更差。目前的研究已经证实小细胞肺癌(small cell lung cancer,SCLC)患者癌细胞中存在ecDNA。本文综述了ecDNA的形成机制并以此为基础讨论了ecDNA在癌细胞中扩增的过程,其促进肿瘤生长,复发和转移的机制以及ecDNA与SCLC高耐药性的关系。最后本文总结了ecDNA富集的SCLC的治疗方向,为未来进一步的研究提供一定指导。 展开更多
关键词 ecdna 小细胞肺癌 肿瘤异质性 癌基因扩增 耐药性
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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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Drug-Drug Interactions in Patients with Breast Cancer
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作者 Balaram Gudapati Terry Oroszi 《Journal of Biosciences and Medicines》 2024年第9期113-131,共19页
The research paper investigates the intricate landscape of drug-drug interactions (DDIs) within the context of breast cancer treatment, with a particular focus on the elderly population and the use of complementary an... The research paper investigates the intricate landscape of drug-drug interactions (DDIs) within the context of breast cancer treatment, with a particular focus on the elderly population and the use of complementary and alternative medicine (CAM). The study underscores the heightened susceptibility of elderly patients to DDIs due to the prevalence of polypharmacy and the widespread utilization of CAM among breast cancer patients. The potential ramifications of DDIs, encompassing adverse drug events and diminished treatment efficacy, are elucidated. The paper accentuates the imperative for healthcare providers to comprehensively understand both conventional and CAM therapies, enabling them to provide patients with informed guidance regarding safe and efficacious treatment options, culminating in enhanced patient outcomes. 展开更多
关键词 Breast Cancer drug-drug Interactions POLYPHARMACY Side effects Anti-Cancer drug Failure Complementary and Alternative Medicine
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Three-dimensional aspects of formulation excipients in drug discovery:a critical assessment on orphan excipients,matrix effects and drug interactions
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作者 Vijayabhaskar Veeravalli Hanumanth Srikanth Cheruvu +1 位作者 Pratima Srivastava Lakshmi Mohan Vamsi Madgula 《Journal of Pharmaceutical Analysis》 SCIE CAS CSCD 2020年第6期522-531,共10页
Formulation/pharmaceutical excipients play a major role in formulating drug candidates,with the objectives of ease of administration,targeted delivery and complete availability.Many excipients used in pharmaceutical f... Formulation/pharmaceutical excipients play a major role in formulating drug candidates,with the objectives of ease of administration,targeted delivery and complete availability.Many excipients used in pharmaceutical formulations are orphanized in preclinical drug discovery.These orphan excipients could enhance formulatability of highly lipophilic compounds.Additionally,they are safe in preclinical species when used below the LD50 values.However,when the excipients are used in formulating compounds with diverse physico-chemical properties,they pose challenges by modulating study results through their bioanalytical matrix effects.Excipients invariably present in study samples and not in the calibration curve standards cause over-/under-estimation of exposures.Thus,the mechanism by which excipients cause matrix effects and strategies to nullify these effects needs to be revisited.Furthermore,formulation excipients cause drug interactions by moderating the pathways of drug metabolizing enzymes and drug transport proteins.Although it is not possible to get rid of excipient driven interactions,it is always advised to be aware of these interactions and apply the knowledge to draw meaningful conclusions from study results.In this review,we will comprehensively discuss a)orphan excipients that have wider applications in preclinical formulations,b)bioanalytical matrix effects and possible approaches to mitigating these effects,and c)excipient driven drug interactions and strategies to alleviate the impacts of drug interactions. 展开更多
关键词 Formulation excipients PRECLINICAL drug discovery Matrix effects drug interactions BIOANALYSIS PHARMACOKINETICS Formulation development
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Methodological challenges to control for immortal time bias in addressing drug effects in type 2 diabetes
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作者 Xi-Lin Yang Xiao-Xu Huo Juliana CN Chan 《World Journal of Methodology》 2015年第3期122-126,共5页
There are multiple biases in using observational studies to examine treatment effects such as those from prevalent drug users, immortal time and drug indications. We used renin angiotensin system(RAS) inhibitors and s... There are multiple biases in using observational studies to examine treatment effects such as those from prevalent drug users, immortal time and drug indications. We used renin angiotensin system(RAS) inhibitors and statins as reference drugs with proven efficacies in randomized clinical trials(RCTs) and examined their effectiveness in the prospective Hong Kong Diabetes Registry using adjustment methods proposed in the literature. Using time-dependent exposures to drug treatments yielded greatly inflated hazard ratios(HR) regarding the treatment effects of these drugs for cardiovascular disease(CVD) in type 2 diabetes. These errors were probably due to changing indications to use these drugs during follow up periods, especially at the time of drug commencement making time-dependent analysis extremely problematic. Using time-fixed analysis with exclusion of immortal time and adjustment for confounders at baseline and/or during follow-up periods, the HR of RAS inhibitors for CVD was comparable to that in RCT. The result supported the use of the Registry for performing pharmacoepidemiological analysis which revealed an attenuated low low-density lipoprotein cholesterol related cancer risk with RAS inhibitors. On the other hand, time-fixed analysis with including immortal time and adjustment for confounders at baseline and/or during follow-up periods, the HR of statins for CVD was similar to that in the RCT. Our results highlight the complexity and difficulty in removing these biases. We call for validations of the methods to cope with immortal time and drug use indications before applying them to particular research questions, so to avoid making erroneous conclusions. 展开更多
关键词 Pharmacoepidemiological analysis IMMORTAL TIME BIAS drug effects Prevalent drug user BIAS drug INDICATION BIAS Type 2 diabetes
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EFFECT OF ANTITUMOR DRUGS ON THE ACTIVITY OF DNA TOPOISOMERASE I
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作者 钱毅 曾桂超 张迺蘅 《Chinese Journal of Cancer Research》 SCIE CAS CSCD 1990年第4期40-44,共5页
The activity of DNA topoisomerase Ⅱ prepared from either normal or tumor tissues were compared. It was found that the unknotting activity of the enzyme in malignant tumor cells was higher than that in normal cells. W... The activity of DNA topoisomerase Ⅱ prepared from either normal or tumor tissues were compared. It was found that the unknotting activity of the enzyme in malignant tumor cells was higher than that in normal cells. We selected some antitumor drugs including Chinese traditional medicine, and observed their effects on the unknotting activity of topoisomerase Ⅱ. The results showed that inhibition of the unknotting activity of the enzyme required very low concentrations of drugs, but much higher concentrations were required for other tested. Some antitumor drugs had no effect on the enzyme were also proved. It is interesting that carrageenan, an antiviral drug, strongly blocked the unknotting activity although its antitumor activity has not been reported. 展开更多
关键词 dna effect OF ANTITUMOR drugS ON THE ACTIVITY OF dna TOPOISOMERASE I
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Preventive Effects of Five Drugs on Mycoplasma Pneumonia of Swine (MPS)
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作者 Zhang Yan Liu Hailong +4 位作者 Lin Zhemin Cao Zongxi Tan Shuyi Chen Xiaojie Xie Yueshan 《Animal Husbandry and Feed Science》 CAS 2016年第5期278-280,共3页
The paper was to explore the preventive effects of five drugs on mycoplasma pneumonia of swine (MPS) and to provide reference for clinical medication of pig farms in Hainan Province. A total of 444 health piglets we... The paper was to explore the preventive effects of five drugs on mycoplasma pneumonia of swine (MPS) and to provide reference for clinical medication of pig farms in Hainan Province. A total of 444 health piglets were randomly divided into 6 groups, including five medication groups (72 piglets in group A, 74 pig- lets in group B, 72 piglets in group C, 76 piglets in group D, 76 piglets in group E) and one control group (74 piglets). The piglets in experimental groups were treated drugs once a day for successive 5 days at 30, 60, 90, 120 and 150 of age. The piglets in control group were free of medication. At 70 and 140 days of age, 15 piglets of each group were randomly selected to collect their blood sermn. The Mycoplasma hyopneumoniae (M-Hyo) antibodies in serum were measured by en- zyme-linked immunosorbent assay (ELISA). During the experiment, the incidence rates of respiratory disease, lung lesion, feed conversion rate, average daily gain (ADG), and mortality rate of pigs were also observed and recorded. The results showed that the five drugs had significant difference in preventative effects. Group C (Zhiyuanjing group) received the best preventive effect and the highest economic benefits. Compared with control group, the ADG and feed conversion rate in group C were increased by 7.53% and 9.09%, respectively; the incidence rate of respiratory disease was reduced by 13.44% and lung lesion was alleviated by 81.43% ; and the earnings of each pig could rise by 132.70 yuan. The preventative effect and economic benefit of the drugs was sequenced by Chansu Kechuanling and Bingchan Kechuanwang. Wante Feilin and amoxicillin had weaker preventive effects against MPS but greatly influenced growth performance of pigs, so they should be used alternatively with other drugs. 展开更多
关键词 Mycoplasma pneumonia of swine (MPS) Mycoplasma hyopneumoniae (M-Hyo) drugS Preventive effect
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