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牛副流感病毒3型NP蛋白在昆虫杆状病毒系统中的表达
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作者 项钰 郭衍冰 +7 位作者 孙兴忠 郝良玉 张天宇 张艺馨 姜乐凡 周子博 王楠 曹利利 《畜牧与兽医》 北大核心 2026年第1期101-106,共6页
为表达牛副流感病毒3型(BPIV3)核衣壳蛋白(NP),利用昆虫表达系统构建pFastBAC-NP重组质粒,经转座获得重组杆粒Bacmid-NP,转染昆虫细胞(Sf9)后获得重组杆状病毒。通过Bacmid-NP感染Sf9细胞表达NP蛋白,利用高浓度咪唑洗脱纯化NP蛋白,利用... 为表达牛副流感病毒3型(BPIV3)核衣壳蛋白(NP),利用昆虫表达系统构建pFastBAC-NP重组质粒,经转座获得重组杆粒Bacmid-NP,转染昆虫细胞(Sf9)后获得重组杆状病毒。通过Bacmid-NP感染Sf9细胞表达NP蛋白,利用高浓度咪唑洗脱纯化NP蛋白,利用半数组织培养感染剂量(TCID_(50))测定病毒滴度,SDS-PAGE和Western blot分析NP蛋白的纯化效果,BCA测定蛋白浓度,并将蛋白免疫小鼠,检测免疫后抗体水平。结果:构建的Bacmid-NP采用pUC/M13通用引物验证,证实NP基因成功克隆至Bacmid杆粒;P3代重组病毒的TCID_(50)为10^(-6.86)/0.1 mL;Bacmid-NP传代后Western blot检测,可在67 ku出现特异性条带;通过SDS-PAGE对感染Bacmid-NP的Sf9细胞进行检测,结果表明上清液与沉淀均可表达;Western blot鉴定结果表明67 ku左右有特异性反应条带,说明NP蛋白可以分泌表达;采用镍柱纯化,SDSPAGE鉴定纯化效果,并将纯化蛋白与BPIV3阳性血清进行Western blot试验,结果显示纯化蛋白为单条带,可以与阳性血清特异性结合,蛋白浓度为0.596 mg/mL,免疫小鼠后血清效价可达1∶64000。综上,本试验利用昆虫表达系统成功表达了NP蛋白,为进一步建立检测方法和疫苗研制提供了技术基础。 展开更多
关键词 牛副流感病毒3型 杆状病毒表达系统 np蛋白
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从能否去掉“的”再探“NP的VP”结构
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作者 闫晓凤 《现代语言学》 2026年第1期755-761,共7页
从“这本书的出版”引发的关于“NP的VP”的结构问题学术界已展开众多讨论。不同于大多聚焦于词类及其转换的研究,本文从实际语料出发,将重点讨论能否去掉“的”,分析这一特殊用法的表现特征及形成的原因。本文发现,在去掉“的”不影响... 从“这本书的出版”引发的关于“NP的VP”的结构问题学术界已展开众多讨论。不同于大多聚焦于词类及其转换的研究,本文从实际语料出发,将重点讨论能否去掉“的”,分析这一特殊用法的表现特征及形成的原因。本文发现,在去掉“的”不影响语用的句子中,VP主要由一般或具体的动词构成,并与前面的名词构成主动关系;在去掉“的”后不成立或难以成立的句子中,动词多为抽象的动词,转化为名词义的能力较强,对“的”依赖性较强,此时动词与“的”前面的名词多构成被动关系。后者中的动词很可能是兼类词,其名词义与动词义都被广泛应用。上述现象表明,“NP的VP”结构中“的”的可省略性,与动词的名物化倾向及其兼类属性密切相关。 展开更多
关键词 名物化 np的VP 动词 兼类
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携带DEV-gB/NP28重组减毒沙门氏菌诱导鸭的免疫应答研究 被引量:3
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作者 鲜思美 李婷 +4 位作者 冯将 李鹏飞 包细明 张益 文明 《中国预防兽医学报》 CAS CSCD 北大核心 2018年第4期330-335,共6页
为探究表达鸭肠炎病毒(DEV)gB/NP28双基因重组减毒沙门菌口服疫苗在鸭体内诱导免疫应答能力,本研究将构建的重组菌(pcDNA3.1-DEV-gB/NP28)/SL7207、DVE弱毒疫苗、重组质粒pcDNA3.1-DEV-gB/NP28及PBS分别免疫雏鸭,通过间接免疫荧光法检... 为探究表达鸭肠炎病毒(DEV)gB/NP28双基因重组减毒沙门菌口服疫苗在鸭体内诱导免疫应答能力,本研究将构建的重组菌(pcDNA3.1-DEV-gB/NP28)/SL7207、DVE弱毒疫苗、重组质粒pcDNA3.1-DEV-gB/NP28及PBS分别免疫雏鸭,通过间接免疫荧光法检测免疫鸭脾脏、胸腺、法氏囊、哈德氏腺组织中的抗原表达;双抗体夹心ELISA方法检测肠道黏膜sIgA;间接ELISA方法监测血清中DEV特异性抗体、外周血T淋巴细胞增殖及IFN-γ、IL-4细胞因子含量,对该口服疫苗进行免疫学评价。结果表明,重组菌能够诱导鸭产生良好的黏膜免疫、体液免疫和细胞免疫应答;攻毒试验显示,在DVE强毒攻击下重组菌免疫可提供75%以上的保护,表明重组菌免疫对DEV攻击具有一定的免疫保护作用。 展开更多
关键词 鸭病毒性肠炎病毒 GB基因 np28基因 减毒沙门氏菌 免疫应答
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应用SYBR GreenⅠ荧光定量PCR方法检测人工感染雏鸭体内DEV NP基因表达水平 被引量:2
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作者 杨颖 夏梦 +3 位作者 殷俊磊 杜海燕 周碧君 文明 《浙江农业学报》 CSCD 北大核心 2011年第4期703-707,共5页
为阐明DEV的感染与致病机理,更深入地研究病原与鸭体的相互关系。将鸭肠炎病毒(DEV)强毒GZ株经腿部肌肉注射感染15日龄雏鸭后,应用建立的SYBR GreenⅠ荧光定量PCR方法对NP(病毒核衣壳蛋白)基因转录物进行定量,以检测NP基因在雏鸭体内各... 为阐明DEV的感染与致病机理,更深入地研究病原与鸭体的相互关系。将鸭肠炎病毒(DEV)强毒GZ株经腿部肌肉注射感染15日龄雏鸭后,应用建立的SYBR GreenⅠ荧光定量PCR方法对NP(病毒核衣壳蛋白)基因转录物进行定量,以检测NP基因在雏鸭体内各组织的表达水平。结果显示:NP基因在所检组织中均有表达,感染后3 h即可在肝、脾、脑、胸腺、肾和肺6种组织中检测到NP基因的表达;感染后6 h,除上述组织外还可在十二指肠和盲肠检测出;感染后10 h又可在胸肌和心肌等检测出。不同受检组织检出量有所不同,且在感染后30或48 h达到高峰,持续至96 h,之后均有所下降。 展开更多
关键词 鸭肠炎病毒 np基因 实时荧光定量PCR 雏鸭
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携带DEV-NP28/gB双基因DNA疫苗减毒沙门氏菌的构建 被引量:2
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作者 王相金 文明 +3 位作者 周碧君 王开功 程振涛 汪德生 《生物技术》 CAS CSCD 北大核心 2013年第4期36-40,共5页
目的:构建携带pcDNA3.1-DEV-NP28/gB双基因DNA疫苗减毒沙门氏菌。方法:大量培养含pcDNA3.1-DEVNP28/gB大肠杆菌DH5α,提取重组质粒,转化至感受态减毒沙门氏菌SL7207中,培养后再提取重组质粒,通过双酶切、PCR和序列测序进行鉴定。结果:... 目的:构建携带pcDNA3.1-DEV-NP28/gB双基因DNA疫苗减毒沙门氏菌。方法:大量培养含pcDNA3.1-DEVNP28/gB大肠杆菌DH5α,提取重组质粒,转化至感受态减毒沙门氏菌SL7207中,培养后再提取重组质粒,通过双酶切、PCR和序列测序进行鉴定。结果:经对重组质粒双酶切和PCR后,均可得到与预期大小相一致的DNA片段(1 062bp);测序发现重组质粒目的基因序列与预期设计一致。结论:成功构建了携带pcDNA3.1-DEV-NP28/gB的减毒沙门氏菌SL7207。 展开更多
关键词 鸭肠炎病毒 np基因 GB基因 DNA疫苗 减毒沙门氏菌 构建
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结肠癌中高表达delta Np63基因和蛋白的临床意义
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作者 粟珏佳 杨云峰 +2 位作者 韩军 陈建川 张青平 《生命科学研究》 CAS CSCD 北大核心 2012年第5期438-440,465,共4页
了解结肠癌组织中delta Np63基因和蛋白的表达情况,探讨其表达变化的临床价值和意义.采用RT-PCR(reverse transcriptase-polymerase chain reaction)的方法检测delta Np63基因的表达,Western blot检测deltaNp63蛋白的表达.结肠癌组织中d... 了解结肠癌组织中delta Np63基因和蛋白的表达情况,探讨其表达变化的临床价值和意义.采用RT-PCR(reverse transcriptase-polymerase chain reaction)的方法检测delta Np63基因的表达,Western blot检测deltaNp63蛋白的表达.结肠癌组织中delta Np63基因和蛋白的表达明显高于癌旁正常组织(P<0.05).并且与肿瘤病理分级和临床分期密切相关(P<0.05).这一结果提示delta Np63基因可能在结肠癌疾病进展中发挥重要作用. 展开更多
关键词 deLTA np63 结肠癌 表达
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Zincophilic Ti_(3)C_(2)Cl_(2)MXene and anti-corrosive Cu NPs for synergistically regulated deposition of dendrite-free Zn metal anode 被引量:4
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作者 Yunfei Shen Yi Liu +7 位作者 Kaisheng Sun Tiantian Gu Gang Wang Yue Yang Jianxiang Pang Yang Zheng Xiaodong Yang Long Chen 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2024年第2期137-147,共11页
Dendrites growth,chemical corrosion,and hydrogen evolution reaction(HER)on zinc anodes are the main barriers for the development of aqueous zinc-ion batteries(AZIBs).Constructing interfacial protec-tive layer is an ef... Dendrites growth,chemical corrosion,and hydrogen evolution reaction(HER)on zinc anodes are the main barriers for the development of aqueous zinc-ion batteries(AZIBs).Constructing interfacial protec-tive layer is an effective way to alleviate the side reactions on the anodes.Herein,Cu/Ti_(3)C_(2)Cl_(2)MXene(CMX)with high zincophilic and hydrophobic property is prepared by the lewis molten salts etching method,and the CMX interface protection layer is constructed by a simple spin coating.The CMX coat-ing layer can provide abundant nucleation sites and uniformize the charge distribution through the zin-cophilic Ti_(3)C_(2)Cl_(2)MXene matrix,leading to homogenous Zn deposition.In addition,the hydrophobic coat-ing contained anti-corrosive Cu nanoparticles can prevent the Zn anode from the electrolyte,beneficial for suppressing the chemical corrosion and HER.Therefore,the stable and reversible Zn plating/stripping is achieved for the Zn anode coated by the CMX,which exhibits the lifespan of over 1400 h at 0.5 mA cm^(−2),and even can steadily run for 700 h with 65 mV at 10 mA cm^(−2).Furthermore,CMX@Zn shows a high coulombic efficiency of over 100%for 3800 cycles,which indicates that the CMX@Zn electrode has excellent stability and reversibility of Zn stripping/plating.The full batteries assembled with ZnCoMnO/C(ZCM)cathodes also exhibits higher capacity(450.6 mAh g^(−1)at 0.1 A g^(−1))and cycle stability(capacity retention of 70%after 1500 cycles).This work enhanced the lifespan of AZIBs and broaden the research of multifunctional coating layer to other secondary batteries based on metal anodes. 展开更多
关键词 Zinc anode Spin coating Zincophilic MXene Anti-corrosive Cu nps Multifunctional coating
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Analysis of prompt fission neutron spectrum and multiplicity for ^(237)Np(n, f) in the frame of multi-modal Los Alamos model 被引量:1
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作者 郑娜 丁毅 +2 位作者 钟春来 陈金象 樊铁栓 《Chinese Physics B》 SCIE EI CAS CSCD 2009年第4期1413-1420,共8页
The improved version of Los Alamos model with the multi-modal fission approach is used to analyse the prompt fission neutron spectrum and multiplicity for the neutron-induced fission of 237Np. The spectra of neutrons ... The improved version of Los Alamos model with the multi-modal fission approach is used to analyse the prompt fission neutron spectrum and multiplicity for the neutron-induced fission of 237Np. The spectra of neutrons emitted from fragments for the three most dominant fission modes (standard Ⅰ, standard Ⅱ and superlong) are calculated separately and the total spectrum is synthesized. The multi-modal parameters contained in the spectrum model are determined on the basis of experimental data of fission fragment mass distributions. The calculated total prompt fission neutron spectrum and multiplicity are better agreement with the experimental data than those obtained from the conventional treatment of the Los Alamos model. 展开更多
关键词 237np(n f) prompt neutron spectrum neutron multiplicity multi-modal model LosAlamos model
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Upregulation of cell adhesion through delta Np63 silencing in human 5637 bladder cancer cells 被引量:1
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作者 Yun-Feng He Dai-Yin Tian +4 位作者 Zheng-Jin Yi Zhi-Kang Yin Chun-Li Luo Wei Tang Xiao-Hou Wu 《Asian Journal of Andrology》 SCIE CAS CSCD 2012年第5期788-792,共5页
Some researchs have demonstrated that the loss of delta Np63 is associated with aggressive phenotypes and poor prognosis. However, other research indicates that delta Np63 is considered to have oncogenic properties. D... Some researchs have demonstrated that the loss of delta Np63 is associated with aggressive phenotypes and poor prognosis. However, other research indicates that delta Np63 is considered to have oncogenic properties. Delta Np63 overexpression is often observed in association with the oncogenic growth of squamous cell carcinomas and bladder cancer. In this study, we investigated the oncogenic role of delta Np63 in regulating cell adhesion in transitional cell carcinoma of the bladder (TCCB). The cells were stably transfected with the delta Np63 short hairpin RNA (shRNA) plasmid. Immunocytochemistry was performed to determine the knockdown efficiency. Tumour cells were studied for their ability to adhere to vascular endothelial cells. Confocal microscopy was used to analyse the changes in cytoskeletal F-actin. F-actin expression was measured by flow cytometry. Cell invasion ability was assessed using transwell chambers. The delta Np63-silenced tumour cells were shown to adhere more tightly than controls to vascular endothelial cells (P〈0.05). The content of F-actin in the delta Np63-silenced cells was enhanced (P〈0.05). The Matrigel invasion assays showed that human 5637 bladder cancer cells had a lower degree of motility when transfected with pdelta Np63-shRNA (P〈0.05). In conclusion, silencing of the delta Np63 expression can enhance the adhesiveness of 5637 cells by inducing F-actin cytoskeleton production, and it will possibly inhibit the TCCB invasion and metastasis. 展开更多
关键词 bladder transitional cell carcinoma cell adhesion delta np63
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Detection of minor constituents in TongMai Granules using NP×RP off-line twodimensional liquid chromatography coupled with orbitrap mass spectrometry 被引量:1
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作者 Lulu Xu Zhanpeng Shang +4 位作者 Yue Chai Yang Zhang Rong Yu Min Ye Xue Qiao 《Journal of Chinese Pharmaceutical Sciences》 CAS CSCD 2020年第11期793-803,共11页
TongMai Granules is a Chinese medicine patent drug to treat cardiovascular diseases.It is prepared from the water extract of Dan-shen,Chuan-xiong and Ge-gen.The main compounds of TongMai Granules are isoflavone glycos... TongMai Granules is a Chinese medicine patent drug to treat cardiovascular diseases.It is prepared from the water extract of Dan-shen,Chuan-xiong and Ge-gen.The main compounds of TongMai Granules are isoflavone glycosides,isoflavones,and phenolic acids.However,it is difficult to detect low-polar compounds such as tanshinones and phthalides though they may also contribute to the therapeutic effect.In this work,an off-line two-dimensional chromatography method was developed to enrich the minor constituents in TongMai Granules.The extract was subjected to an SEP-PAK silica SPE column and eluted with petroleum ether,ethyl acetate–methanol(6:1,v/v),and methanol,successively.The three fractions were then analyzed using ultra-high performance liquid chromatography coupled with orbitrap mass spectrometry(UHPLC/orbitrap-MS).The isoflavones from Ge-gen,phenolic acids from Dan-shen and phthalides from Chuan-xiong were distributed in different fractions.A total of 131 compounds,including 59 from Ge-gen,26 from Dan-shen,43 from Chuan-xiong,and 3 common ones from Dan-shen and Chuan-xiong were tentatively identified.Among them,26 compounds were identified by comparing with reference standards.This study set a good example for comprehensive analysis of the constituents in traditional Chinese medicine formula. 展开更多
关键词 TongMai Granules Off-line two-dimensional chromatography np×RP UHPLC/orbitrap-MS
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Syntheses and Crystal Structures of Silver(I) Complexes by Depolymerizing [Ag(C≡CPh)]_n with a NP_3 Ligand 被引量:1
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作者 马震 林韵 陈忠宁 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2005年第3期339-345,共7页
Two silver(I) complexes were prepared by the reaction of [Ag(C≡CPh)]n with NP3 [NP3 = N(CH2CH2PPh2)3] or with NP3 and [Cu(CH3CN)4]ClO4. Complex 1 [(Ag2Cl(NP3)2)(Ag5- (C≡CPh)6)] contains both NP3 and PhC≡C- ligand... Two silver(I) complexes were prepared by the reaction of [Ag(C≡CPh)]n with NP3 [NP3 = N(CH2CH2PPh2)3] or with NP3 and [Cu(CH3CN)4]ClO4. Complex 1 [(Ag2Cl(NP3)2)(Ag5- (C≡CPh)6)] contains both NP3 and PhC≡C- ligands. The complex cation is (Ag2Cl(NP3)2)+, in which two Ag(NP3)+ cations were bridged by a Cl- donor. The anion is (Ag5(C≡CPh)6)-, where five Ag+ ions are linked by six C≡CPh- to form a pentanuclear cluster. Complex 2 only contains NP3 ligand, where the silver center adopts a trigonal-bipyramidal geometry. Crystal data for 1: C133H116Ag7Cl3- N2P6, Mr = 2789.54, triclinic, space group P1, a = 13.0780(2), b = 15.3678(2), c = 31.2041(3) ?, α = 91.3928(7), β = 90.9328(8), γ = 96.0244(4)o, V = 6233.8(1) ?3, T = 293(2) K, Z = 2, Dc = 1.486 g/cm3, F(000) = 2796, μ = 1.266 mm-1, the final R = 0.0746 and wR = 0.1953 for 16475 observed reflections with I > 2σ(I). Crystal data for 2: C42H42AgClNO4P3, Mr = 861.00, trigonal, space group R3, a = 17.451(1), b = 17.451(1), c = 11.3985(7) ?, V = 3006.0(3) ?3, T = 293(2) K, Z = 3, Dc = 1.427 g/cm3, F(000) = 1326, μ = 0.731 mm-1, the final R = 0.0251 and wR = 0.0663 for 1499 observed reflections with I > 2σ(I). 展开更多
关键词 ACETYLIde crystal structure np3 ligand silver(I) complexes
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New method for detection fusion of MAC based on DCM and NP rule 被引量:1
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作者 Zhenhua Xu Jianguo Huang Qunfei Zhang 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2012年第4期612-617,共6页
The problem of distributed detection fusion using multiple sensors for remote underwater target detection is studied. Considering that multiple access channel (MAC) schemes are able to offer high efficiency in bandw... The problem of distributed detection fusion using multiple sensors for remote underwater target detection is studied. Considering that multiple access channel (MAC) schemes are able to offer high efficiency in bandwidth usage and consume less energy than the parallel access channel (PAC), the MAC scheme is introduced into the underwater target detection field. The model of underwater distributed detection fusion based on MAC schemes is established. A new method for detection fusion of MAC based on deflection coefficient maximization (DCM) and Neyman-Pearson (NP) rule is proposed. Under the power constraint of local sensors, this paper uses the DCM theory to derive the optimal weight coefficients and offsets. The closed-form expressions of detection probability and false alarm probability for fusion systems are obtained. The optimal detection performance of fusion systems is analyzed and deeply researched. Both the theory analysis and simulation experiments indicate that the proposed method could improve the detection performance and decrease the error probability effectively under power constraints of local sensors and low signal to noise ratio. 展开更多
关键词 deflection coefficient maximization (DCM) multipleaccess channel (MAC) Neyman-Pearson np rule detection fusion target detection.
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Rabbit Defensin(NP-1) Gene Transformation of Wheat and In Vitro Microbicidal Activity Assay of Transgenic Plants 被引量:1
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作者 郭殿京 《High Technology Letters》 EI CAS 1999年第1期96-99,共4页
Monocot high expression vector pBARUNP1, harboring rabbit defensin(NP 1) gene and selective bar gene for resistance to the herbicide Basta, were constructed and then transferred into immature embryos of wheat (“Bobw... Monocot high expression vector pBARUNP1, harboring rabbit defensin(NP 1) gene and selective bar gene for resistance to the herbicide Basta, were constructed and then transferred into immature embryos of wheat (“Bobwhite” and “Zhong 60634”)via particle bombardment. Southern and RNA dot blots showed the stable integration and transcription of foreign NP 1 gene in the wheat genome. Furthermore, in vitro microbicidal activity assay indicated the proper translation of defensin. Crude protein extraction of transgenic plants exhibited to some extent cytotoxic to several pathogens including G. saubinetii, B. subtilis, E.coli, and A. tumefaciens. 展开更多
关键词 WHEAT RABBIT defensin(np 1)gene TRANSGENIC plant In VITRO microbicidal activity ASSAY
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Polyethylene glycol phospholipids encapsulated silicon 2,3-naphthalocyanine dihydroxide nanoparticles(SiNcOH-DSPE-PEG(NH2)NPs) for single NIR laser induced cancer combination therapy 被引量:3
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作者 Jing-Ping Wei Xiao-Lan Chen +4 位作者 Xiao-Yong Wang Jing-Chao Li Sai-Ge Shi Gang Liu Nan-Feng Zheng 《Chinese Chemical Letters》 SCIE CAS CSCD 2017年第6期1290-1299,共10页
Currently,the combination of photothermal therapy(PTT) and photodynamic therapy(PDT) has emerged as a powerful technique for cancer treatment.However,most examples of combined PTT and PDT reported use multi-compon... Currently,the combination of photothermal therapy(PTT) and photodynamic therapy(PDT) has emerged as a powerful technique for cancer treatment.However,most examples of combined PTT and PDT reported use multi-component nanocomposites under excitation of separate wavelength,resulting in complex treatment process.In this work,a novel theranostic nanoplatform(SiNcOH-DSPE-PEG(NH2)NPs) has been successfully developed by coating silicon 2,3-naphthalocyanine dihydroxide(SiNcOH)with DSPE-PEG and DSPE-PEG-NH2 for photoacoustic(PA) imaging-guided PTT and PDT tumor ablation for the first time.The as-prepared single-agent SiNcOH-DSPE-PEG(NH2) NPs not only have good water solubility and biocompatibility,but also exhibit high photothermal conversion efficiency and singlet oxygen generation capability upon 808 nm NIR laser irradiation.In addition,owing to their high absorption at NIR region,the SiNcOH-DSPE-PEG(NH2) NPs can also be employed as an effective diagnostic nanoagent for photoacoustic(PA) imaging.In vitro and in vivo experimental results clearly indicated that the simultaneously combined PTT and PDT under the guidance of PA imaging with single NIR laser excitation can effectively kill cancer cells or eradicate tumor tissues.Taking facile synthesis and high efficiency in cancer treatment by SiNcOH-DSPE-PEG(NH2) NPs into consideration,our study provides a promising strategy to realize molecular imaging-guided combination therapy. 展开更多
关键词 SiNcOH-DSPE-PEG(NH2) nps Photothermal therapy(PTT) Photodynamic therapy(PDT) Photoacoustic(PA) imaging Combinatorial PTT/PDT
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环境水样中^(237)Np和^(241)Am分析方法的研究进展
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作者 文雯 娄海林 +3 位作者 文富平 王绍林 丛日俐 李玉芹 《核电子学与探测技术》 北大核心 2025年第10期1569-1584,共16页
环境样品中放射性核素的分析测量是辐射防护和辐射监测的关键过程,对评估放射性核素的环境影响和放射性风险具有重要意义。本文综述了环境水样中^(237)Np和^(241)Am分析方法的研究现状,在目前环境中^(237)Np和^(241)Am的放射性水平以及N... 环境样品中放射性核素的分析测量是辐射防护和辐射监测的关键过程,对评估放射性核素的环境影响和放射性风险具有重要意义。本文综述了环境水样中^(237)Np和^(241)Am分析方法的研究现状,在目前环境中^(237)Np和^(241)Am的放射性水平以及Np和Am化学性质的基础上,对水样预处理、分离纯化和测量三个方面进行了详细综述,总结分析了目前环境水样^(237)Np和^(241)Am分析方法的特点和难点,并展望了未来环境水样中^(237)Np和^(241)Am分析技术的发展方向。 展开更多
关键词 水样 ^(237)np ^(241)Am 分析 测量
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深地低本底辐射环境对NP69人鼻咽上皮细胞增殖迁移的抑制效应及机制
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作者 郝智贞 李灿 +6 位作者 王领 邹宇豪 文继锐 吴江 万学红 刘锋 刘吉峰 《四川大学学报(医学版)》 北大核心 2025年第5期1336-1343,共8页
目的本研究旨在探究深地低本底辐射环境对NP69人鼻咽上皮细胞生物学行为的影响及其潜在分子机制。方法采用平行对照实验设计,分别于中国深地原位生命观测站(China in situ Deep-Underground Facility&Life Observatory,DeUFO)地表0 ... 目的本研究旨在探究深地低本底辐射环境对NP69人鼻咽上皮细胞生物学行为的影响及其潜在分子机制。方法采用平行对照实验设计,分别于中国深地原位生命观测站(China in situ Deep-Underground Facility&Life Observatory,DeUFO)地表0 m(DeUFO-0 m)、埋深1000 m(DeUFO-1000 m)、埋深1500 m(DeUFO-1500 m)同步培养NP69人鼻咽上皮细胞。通过Cell Counting Kit-8(CCK-8)法和划痕实验等分别检测细胞增殖及迁移能力变化,并利用高通量转录组测序(RNA sequencing,RNA-Seq)分析差异表达基因(differentially expressed genes,DEGs)。采用基因本体(Gene Ontology,GO)和京都基因与基因组百科全书(Kyoto Encyclopedia of Genes and Genomes,KEGG)数据库对差异基因进行功能注释及通路富集分析。结果CCK8显示,培养72 h后,DeUFO-0 m组的吸光度值分别为DeUFO-1000 m组、DeUFO-1500 m组的1.35倍和1.27倍(均P<0.0001);培养96 h后,DeUFO-0 m组的吸光度值分别为DeUFO-1000 m组、DeUFO-1500 m组的1.52倍和1.41倍(均P<0.0001)。克隆形成实验显示,DeUFO-0 m组的细胞克隆数分别为DeUFO-1000 m组、DeUFO-1500 m组的1.59倍和1.27倍(均P<0.001)。划痕实验显示,DeUFO-0 m组36 h愈合率分别为DeUFO-1000 m组、DeUFO-1500 m组的2.22倍和4.00倍(均P<0.0001)。Transwell实验显示,DeUFO-0 m组的迁移细胞数分别为DeUFO-1000 m组、DeUFO-1500 m组的2.08倍和2.56倍(均P<0.0001)。转录组测序分析显示,CELF2、CELF4、CGB8、GRHL2和DMRTA2基因在深地不同埋深实验组中均呈现一致性上调表达。通路富集分析表明,细胞外基质(extracellular matrix,ECM)重构相关通路及基因表达调控通路在实验组中显著富集(FDR<0.05)。结论深地低本底辐射环境可通过调控CELF家族基因等靶点,介导ECM重塑及转录后调控机制,进而抑制NP69人鼻咽上皮细胞的增殖与迁移活性。本研究为环境辐射剂量-细胞效应量效关系的建立提供了实验依据。 展开更多
关键词 深地医学 低本底辐射环境 np69人鼻咽上皮细胞 细胞增殖/迁移 转录组学
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“NP的VP”式的DP结构重议
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作者 曹道根 潘海华 《语言科学》 北大核心 2025年第4期362-375,共14页
文章重新论证"NP的VP"式(如"这本书的出版")具有"内动外名"的句法构造。主要观点如下:1)只要承认其中"NP的"是领有成分,就必须承认此式有(零形)D功能投射,即此式有外层名词性句法构造。2)此式... 文章重新论证"NP的VP"式(如"这本书的出版")具有"内动外名"的句法构造。主要观点如下:1)只要承认其中"NP的"是领有成分,就必须承认此式有(零形)D功能投射,即此式有外层名词性句法构造。2)此式内层谓词性结构通常为词汇层VP或题元层vP/VoiceP,但名物化层级也存在向形态层最为有限的功能扩展。3)按所述物化事件是否涉及可数性特征核验或是否有数量描述,此式外层名词性架构区分为两类,差别在于DP内是否包含量词性轻名投射;量词性轻名词同时在语义和句法层面实现名物化。4)DP不含轻名投射的情形下(即[DP-VP]型式),领有名词移位生成;反之(即[DP-nP-VP]型式),领有名词基础生成于[Spec,DP],并成为VP中空主语或空宾语Pro的控制成分。5)"的"在此式中只是领格标记,既不构成此式作为名物化结构的结构中心,也不构成"NP的"这一领有短语的结构中心;"的"在此式中没有发生功能投射。 展开更多
关键词 名物化 np的VP DP结构
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Purification and Characterization of a Nonylphenol (NP)-degrading Enzyme from Bacillus cereus.Frankland
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作者 YANG Ge ZHANG Ying BAI Yanfen 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2011年第4期644-648,共5页
An extracellular NP-degrading enzyme secreted by Bacillus cereus.Frankland was purified to homogeneity by a combination of ammonium sulfate precipitation,Phenyl-Sepharose hydrophobic-interaction chromatography and DEA... An extracellular NP-degrading enzyme secreted by Bacillus cereus.Frankland was purified to homogeneity by a combination of ammonium sulfate precipitation,Phenyl-Sepharose hydrophobic-interaction chromatography and DEAE anion-exchange chromatography.On SDS(sodium dodecyl sulfate)-polyacrylamide gel electrophoresis analysis,the purified enzyme showed a relative molecular mass of 58.3 kDa.The depolymerzation of subunits was accompanied with the loss of NP-degrading enzyme activity,and removing denaturing factors by dialysis could restore the dimer structure and enzymatic activity.The enzyme had an isoelectric point of 5.5 and an optimal temperature of 60℃,and was the most active at pH 6.0.The enzymatic activity was stable at pH 4-8 and inhibited by Cu2+.TenN-terminal amino acids were determined to be ASVNSIKIGY,demonstrating that the purified enzyme was a novel one.The hydrolysis pattern of the purified enzyme indicated that the NP-degrading enzyme was an endo NP-degrading enzyme.The extraordinary thermo-stability provided the enzyme with a good prospect to be used as a new tool for clean-production process for textile industry. 展开更多
关键词 nonylphenol(np Bacillus cereus.Frankland np-degrading enzyme PURIFICATION CHARACTERIZATION
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English BNP identification based on corpus-trained decision tree
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作者 孟遥 赵铁军 +1 位作者 李生 张晓光 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2001年第4期383-386,共4页
Finding simple, non recursive, base noun phrase is an important step for many natural language processing applications. This paper presents a new corpus based approach using decision tree for that purpose. In contrast... Finding simple, non recursive, base noun phrase is an important step for many natural language processing applications. This paper presents a new corpus based approach using decision tree for that purpose. In contrast to previous methods for Base NP identification, we adopt a decision tree trained from Penn Treebank to identify Base NP. And a self learning mechanism is further integrated into our model. Experimental results show good performances using our method. The method can also be applied to processing of any other language. 展开更多
关键词 Base np decision tree CORPUS
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基于NP语言的证据加密研究综述
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作者 王玉珠 张明武 《密码学报(中英文)》 北大核心 2025年第2期247-264,共18页
基于NP语言的证据加密是一种无需密钥生成阶段的新型加密方案,解密者拥有某NP问题实例对应的证据而不是密钥,这意味着接收者不需要事先指定,仅有拥有解密能力者(证据)才能解密.由于双方在通信之前不需要交换密钥,证据加密有很多有趣的... 基于NP语言的证据加密是一种无需密钥生成阶段的新型加密方案,解密者拥有某NP问题实例对应的证据而不是密钥,这意味着接收者不需要事先指定,仅有拥有解密能力者(证据)才能解密.由于双方在通信之前不需要交换密钥,证据加密有很多有趣的应用场景.另一方面,证据加密不仅是独立的加密原语,还可作为基础部件用于构造其他强大的密码学方案.目前,证据加密已受到研究人员的广泛重视,其研究方向主要分为两个分支.其一是通用证据加密,这类方案能支持所有NP问题,但大多依赖于强假设条件.其二是仅支持特定NP语言的证据加密,该分支着重基于经过深入研究的密码学假设,致力于实现实用性强的构造方案.本文对证据加密的安全模型、方案设计等作综述性研究和比较分析,探讨了经典的证据加密方案,归纳了证据加密的不同安全框架,剖析了证据加密的典型变体,同时对证据加密在构建其他密码原语方面的应用进行比较分析.最后结合证据加密相关的类似原语对今后的研究方向进行展望. 展开更多
关键词 证据加密 np语言 np完全语言 多线性映射 不可区分性混淆
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