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Sonic Hedgehog及其受体Patched在小鼠视交叉发育过程中的表达 被引量:3
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作者 郝彦利 陈新安 《神经解剖学杂志》 CAS CSCD 北大核心 2005年第4期333-339,共7页
在小鼠胚胎发育过程中,胚胎第13d(E13)至15d(E15)是视交叉发育的主要阶段。在本研究中,我们观察了在E13~E15,Sonic Hedgehog(Shh)及其受体Patched(Ptc)在视觉传导通路的表达。结果发现:在视交叉和视束中,Shh在视神经纤维接近中线时表... 在小鼠胚胎发育过程中,胚胎第13d(E13)至15d(E15)是视交叉发育的主要阶段。在本研究中,我们观察了在E13~E15,Sonic Hedgehog(Shh)及其受体Patched(Ptc)在视觉传导通路的表达。结果发现:在视交叉和视束中,Shh在视神经纤维接近中线时表达上调,越过中线后表达下调,并且主要表达在较深的区域。Ptc在E13~E14的视网膜和E14~E15的视束中有表达,但在视交叉中无表达。Ptc,而不是Shh,表达在体外培养的生长锥中。Shh和Ptc在视觉传导通路发育中的表达提示Shh可能在引导视神经生长方面发挥一定作用。 展开更多
关键词 Sonic HEDGEHOG 受体patched 小鼠 视交叉 视觉传导通路发育
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patched基因在肝细胞癌中的表达及意义 被引量:1
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作者 刘云建 黄淑红 +3 位作者 陈连周 薛玲 张红卫 汪谦 《山东医药》 CAS 北大核心 2007年第6期13-14,共2页
目的探讨patched(Ptc)基因在肝细胞癌(HCC)中的表达及其临床意义。方法采用组织芯片技术和免疫组化(ABC-HRP)法对150例HCC手术切除标本进行Ptc检测,评估Ptc的表达与HCC临床病理的关系。结果150例肝癌组织,脱片9例,141例中39例有高表达(2... 目的探讨patched(Ptc)基因在肝细胞癌(HCC)中的表达及其临床意义。方法采用组织芯片技术和免疫组化(ABC-HRP)法对150例HCC手术切除标本进行Ptc检测,评估Ptc的表达与HCC临床病理的关系。结果150例肝癌组织,脱片9例,141例中39例有高表达(26.6%);25例癌旁肝组织无脱片,阳性表达3例(12.0%)。二者比较有显著性差异(P<0.05)。Ptc阳性表达与HCC的转移、淋巴浸润、包膜形成及细胞分化密切相关(P<0.05)。结论Ptc检测对估计HCC的转移、复发及预后具有意义。 展开更多
关键词 肝肿瘤 patched 基因
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N-S EQUATION CALCULATIONS ON MULTI-ELEMENT AIRFOILS WITH ZONAL PATCHED GRIDS 被引量:2
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作者 郭同庆 陆志良 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2003年第2期155-158,共4页
For a complex flow about multi-element airfoils a mixed grid method is set up. C-type grids are produced on each element′s body and in their wakes at first, O-type grids are given in the outmost area, and H-type grid... For a complex flow about multi-element airfoils a mixed grid method is set up. C-type grids are produced on each element′s body and in their wakes at first, O-type grids are given in the outmost area, and H-type grids are used in middle additional areas. An algebra method is used to produce the initial grids in each area. And the girds are optimized by elliptical differential equation method. Then C-O-H zonal patched grids around multi-element airfoils are produced automatically and efficiently. A time accurate finite-volume integration method is used to solve the compressible laminar and turbulent Navier-Stokes (N-S) equations on the grids. Computational results prove the method to be effective. 展开更多
关键词 multi-element airfoils zonal patched grids finite-volume method N-S equations
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Patched基因在恶性肿瘤中的表达及其临床意义 被引量:2
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作者 蔡清河 涂海健 余加和 《医学综述》 2009年第4期520-522,共3页
Shh信号通道在胚胎发育过程中对细胞的生长、发育、增殖和分化意义重大,通道的异常会引起肿瘤的发生Patched基因是Shh信号通道中的一种肿瘤抑制基因。近年来的许多研究发现,Patched基因的异常表达与一些恶性肿瘤的发生发展密切相关,P... Shh信号通道在胚胎发育过程中对细胞的生长、发育、增殖和分化意义重大,通道的异常会引起肿瘤的发生Patched基因是Shh信号通道中的一种肿瘤抑制基因。近年来的许多研究发现,Patched基因的异常表达与一些恶性肿瘤的发生发展密切相关,Patched基因可以作为某些恶性肿瘤诊断和评价预后的指标,是某些恶性肿瘤生物治疗的靶标之一。本文就Patched基因在某些恶性肿瘤的表达及其临味意义予以综述。 展开更多
关键词 patched基因 SHH信号通路 恶性肿瘤
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RT-PCR法研究soni chedgehog基因及其受体patched在小鼠牙胚钟状晚期的表达 被引量:1
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作者 周彦秋 林久祥 《北京大学学报(医学版)》 CAS CSCD 北大核心 2002年第2期137-139,共3页
目的 :判断sonichedgehog(Shh)基因及其受体patched(Ptc)是否在小鼠牙胚钟状晚期有表达。 方法 :用RT PCR法研究Shh及其受体Ptc在小鼠牙胚钟状晚期的表达。设计Shh及其受体Ptc的PCR引物 ;选取新生鼠第 1天 (P1)、第 3天 (P3)、第 7天 (... 目的 :判断sonichedgehog(Shh)基因及其受体patched(Ptc)是否在小鼠牙胚钟状晚期有表达。 方法 :用RT PCR法研究Shh及其受体Ptc在小鼠牙胚钟状晚期的表达。设计Shh及其受体Ptc的PCR引物 ;选取新生鼠第 1天 (P1)、第 3天 (P3)、第 7天 (P7)的牙胚为研究对象 ,提取总RNA。两步法进行RT PCR反应 ,10 g·L- 1 琼脂糖电泳观察。结果 :出生后第 1天、第 3天、第 7天小鼠牙胚RT PCR产物可见Shh、Ptc条带。结论 :Shh及其受体Ptc在小鼠牙胚钟状晚期有表达。 展开更多
关键词 RT-PCR法 研究 sonichedgehog基因 受体 patched 小鼠 牙胚钟状 晚期 表达
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sonic hedgehog及patched基因在角化囊肿中的表达
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作者 周彦秋 林久祥 张波 《北京大学学报(医学版)》 CAS CSCD 北大核心 2002年第4期380-383,共4页
目的 :了解Shh(Sonichedgehog) ,Bmp - 4,Ptc(patched)基因在角化囊肿中的表达情况 ,明确Shh及其相关基因在角化囊肿发病中的作用。方法 :选取角化囊肿石蜡切片。将Shh ,Bmp 4,Ptc分别转染与大肠杆菌XL 1 Blue ,提质粒 ,线性化质粒 ,体... 目的 :了解Shh(Sonichedgehog) ,Bmp - 4,Ptc(patched)基因在角化囊肿中的表达情况 ,明确Shh及其相关基因在角化囊肿发病中的作用。方法 :选取角化囊肿石蜡切片。将Shh ,Bmp 4,Ptc分别转染与大肠杆菌XL 1 Blue ,提质粒 ,线性化质粒 ,体外转录法合成地高辛标记的RNA探针 ,原位杂交检测角化囊肿中Shh ,Bmp 4,Ptc的表达情况。结果 :Shh ,Bmp 4共同表达于角化囊肿上皮细胞 ,胞浆呈强阳性表达 ;Ptc表达于角化囊肿间充质细胞 ,胞浆表达较弱。结论 :Shh ,Bmp 4,Ptc在角化囊肿中都有异常表达 ,提示 (1)角化囊肿的发生与生长发育中的上皮残余有关 ;(2 )Shh与Ptc之间平衡的破坏是发生角化囊肿的条件之一 ;(3)角化囊肿与正常生长发育相似 ,存在Bmp 展开更多
关键词 Sonic hedgehog基因 patched基因 角化囊肿 原位杂交 基因表达
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食道鳞状细胞癌组织及癌旁组织中sonic hedgehog和patched1的表达
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作者 张满 崔宏伟 +1 位作者 师迎旭 杨凌 《中国医药导报》 CAS 2015年第32期91-93,F0004,共4页
目的在食道鳞状细胞癌和配对癌旁组织中检测sonic hedgehog(SHH)和patched1(PTCH1)的表达。方法选取内蒙古医科大学附属医院胸外科2012~2014年经手术切除、病理科确诊为食道鳞状细胞癌的标本共30例及其癌旁组织,应用免疫组织化学染... 目的在食道鳞状细胞癌和配对癌旁组织中检测sonic hedgehog(SHH)和patched1(PTCH1)的表达。方法选取内蒙古医科大学附属医院胸外科2012~2014年经手术切除、病理科确诊为食道鳞状细胞癌的标本共30例及其癌旁组织,应用免疫组织化学染色方法检测SHH和patched1的表达。结果在30例食道鳞状细胞癌组织中10例(33.3%)PTCH1阳性表达,肿瘤组织中未检测到SHH蛋白的表达,癌旁组织中未见两种蛋白的表达。PTCH1的表达与患者吸烟、饮酒,食道鳞状细胞癌的肿瘤分化、分期,淋巴结转移无关(P〉0.05)。结论 SHH的表达不是激活hedgehog通路的原因。 展开更多
关键词 食道鳞状细胞癌 癌旁组织 Sonic HEDGEHOG patched1
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Patched基因在结肠癌组织中的表达及意义
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作者 蔡清河 涂海健 +2 位作者 余加和 杨莺卿 谢志勇 《中国医药指南》 2011年第12期179-181,共3页
目的探讨Patched(Ptch)基因在结肠癌组织中的表达及意义。方法应用RT-PCR方法和免疫组织化学对38例结肠癌手术切除的标本进行Ptch基因表达检测,评估Ptch基因表达与结肠癌临床病理的关系。结果癌组织的Patched基因呈高表达,与癌旁组织比... 目的探讨Patched(Ptch)基因在结肠癌组织中的表达及意义。方法应用RT-PCR方法和免疫组织化学对38例结肠癌手术切除的标本进行Ptch基因表达检测,评估Ptch基因表达与结肠癌临床病理的关系。结果癌组织的Patched基因呈高表达,与癌旁组织比较,二者有显著性差异;Ptch基因表达强度与癌的分期密切相关,早期结肠癌的表达强度明显高于进展期癌。结论 Shh信号通路异常的活性状态有可能参与结肠癌的发生过程。Ptch基因检测对评估结肠癌的分期和预后具有重要意义。 展开更多
关键词 肿瘤 结肠 patched基因
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Patched/hedgehog信号通路与膀胱肿瘤关系的研究进展
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作者 胡道琴 谢文练 《岭南现代临床外科》 2007年第1期67-69,共3页
膀胱肿瘤是我国泌尿系统最常见的恶性肿瘤,绝大多数(90%以上)是移行细胞癌,超过70%的移行细胞癌(TCC)在治疗后复发,复发肿瘤中约10%-15%出现恶性程度增加。如果能够明确引起膀胱癌复发的机制,预测膀胱癌复发,将会改进患者... 膀胱肿瘤是我国泌尿系统最常见的恶性肿瘤,绝大多数(90%以上)是移行细胞癌,超过70%的移行细胞癌(TCC)在治疗后复发,复发肿瘤中约10%-15%出现恶性程度增加。如果能够明确引起膀胱癌复发的机制,预测膀胱癌复发,将会改进患者的治疗情况。Hedgehog信号通路在胚胎发育中起着重要的作用。控制着细胞的增殖与命运。近年来人们发现许多疾病都与这个信号通路有关。当这个信号通路异常激活时,会引起肿瘤的发生与发展。本文就Patched/hedgehog信号通路与膀胱肿瘤的关系作一综述。 展开更多
关键词 HEDGEHOG patched 信号通路 膀胱肿瘤 肿瘤关系 HEDGEHOG 移行细胞癌 复发肿瘤
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Shh、Patched和PCNA在子宫肌瘤中的表达 被引量:1
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作者 沈丽萍 胡萍萍 吴晓红 《江苏医药》 CAS CSCD 北大核心 2010年第9期1024-1026,F0002,共4页
目的探讨子宫肌瘤中Sonic hedgehog(Shh)及其受体Patched的表达及与PCNA表达的关系。方法应用免疫荧光染色法检测72例子宫肌瘤组织及对应瘤旁正常组织中Shh、Patched的表达,运用免疫组织化学染色法检测相应标本中PCNA的表达。结果子宫... 目的探讨子宫肌瘤中Sonic hedgehog(Shh)及其受体Patched的表达及与PCNA表达的关系。方法应用免疫荧光染色法检测72例子宫肌瘤组织及对应瘤旁正常组织中Shh、Patched的表达,运用免疫组织化学染色法检测相应标本中PCNA的表达。结果子宫肌瘤中Shh、Patched和PCNA的阳性表达率分别为37.50%、33.33%和87.5%,明显高于瘤旁正常组织的12.5%、8.33%和33.33%(P<0.05)。结论 Shh通路的激活可能通过促进细胞增殖在子宫肌瘤形成过程中起重要作用。 展开更多
关键词 子宫肌瘤 Shh通路 patched PCNA
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The role of the hedgehog/patched signaling pathway in epithelial stem cell proliferation: from fly to human 被引量:3
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作者 PARISIMICHAELJ HAIFANLIN 《Cell Research》 SCIE CAS CSCD 1998年第1期15-21,共7页
The hedgehog-patched (hh-ptc) intercellular signaling pathway has recently been shown to control the proliferation of epithelial stem cells in both Drosophila and vertebrates. Mutant and ectopic expression analyses in... The hedgehog-patched (hh-ptc) intercellular signaling pathway has recently been shown to control the proliferation of epithelial stem cells in both Drosophila and vertebrates. Mutant and ectopic expression analyses in Drosophila suggest that the HH protein diffuses from the signaling cells to promote the proliferation of nearby ovarian somatic stem cells by antagonizing the suppression of its receptor PTC towards the CI transcription factor in the stem cells. Consequently, the transcription of CIdependent genes leads to stem cell proliferation. This regulatory pathway appears to function also in vertebrates,where defects in ptc cause basal cell carcinoma, tumors of epidermal stem cell origin. Basal cell carcinoma can also be induced by ectopic expression of Sonic hedgehog (shh) or Glil, the vertebrate homolog of ci. These studies suggest the conservation of the hh signaling pathway in controlling epithelial stem cell divisions among different organisms. 展开更多
关键词 Stem cell EPITHELIA HEDGEHOG patched Drosophila VERTEBRATE
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PEDOT:PSS-patched magnetic graphene films with tunable dielectric genes for electromagnetic interference shielding and infrared stealth 被引量:2
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作者 Jin-Cheng Shu Yu-Ze Wang Mao-Sheng Cao 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2024年第19期28-36,共9页
The intelligent era brings electronics closer to humans,but also produces a large scale of electromag-netic(EM)radiation simultaneously,which causes serious harm to health and high sophisticated equip-ment.Exploring t... The intelligent era brings electronics closer to humans,but also produces a large scale of electromag-netic(EM)radiation simultaneously,which causes serious harm to health and high sophisticated equip-ment.Exploring the underlying response logic of EM materials is urgently needed to face the challenge of EM interference(EMI)and secondary EM pollution better.Herein,PEDOT:PSS-patched magnetic graphene films are fabricated by vacuum-assisted molecular patching engineering,with tunable EM wave response.Based on the observation of micro-nano structure,the dielectric genes are visually revealed,which offers a bran-new horizon for the optimization of EM properties.Impressively,the constructed films achieve double band shielding toward gigahertz wave and infrared radiation.The optimal EMI shielding efficiency exceeds 99%,and covers the entire X-band.Meanwhile,the green shielding index rises from 0.3 to 0.6,indicating that it is a potential green EMI shielding materials.Furthermore,the periodic macroscopic interfaces and the inherent thermal anisotropy endow the films with thermal insulation and flexible in-frared stealth functions in simulated thermal environments.This work refreshes the insight into multi-band shielding,providing a new idea to EM energy governance. 展开更多
关键词 PEDOT:PSS-patched magnetic graphene films Vacuum-assisted molecular patching engineering Dielectric genes Electromagnetic interference shielding Thermal stealth
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Molecular characterization and expression analysis of Patched 1 gene in the half-smooth tongue sole(Cynoglossus semilaevis)
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作者 DONG Zhongdian QI Qian +4 位作者 ZHANG Ning SHAO Changwei ZHANG Liyan WEN Haishen CHEN Songlin 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2016年第6期19-28,共10页
The signaling molecule hedgehog(Hh) is essential for cellular signaling required for body pattern formation in embryonic and individual development in vertebrate and invertebrates.Patched 1(Ptc1),a receptor of Hh,... The signaling molecule hedgehog(Hh) is essential for cellular signaling required for body pattern formation in embryonic and individual development in vertebrate and invertebrates.Patched 1(Ptc1),a receptor of Hh,mediates the activity of Hh by binging the Hh ligands.In this study,the Ptc1 of half-smooth tongue sole Cynoglossus semilaevis(CsPtc1) was cloned and characterized.The full-length of CsPtc1 cDNA is 5 212 nucleotides(nt),and encodes a protein with 1 543 amino acid residues.CsPtc1 shared many features with Ptc1 of other telesot species.Real-time quantitative PCR revealed CsPtc1 mRNA expressed in brain,liver,heart,gill,intestines,spleen,gonad and kidney,with expression level in testis significantly higher than in ovary.In testis,hybridization signals were mainly detected in primary spermatocytes,secondary spermatocytes,and sertoli cells,while weak signals were found in oocytes.Correspondingly,the degree of methylation is higher in female than in male and pseudomale.Results indicate that CsPtc1 may be involved in Desert Hedgehog(DHH) maintenance of the male and pseudo-male germ line and spermatogenesis. 展开更多
关键词 half-smooth tongue sole male and female patched 1 RACE QRT-PCR METHYLATION
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CyclinD(-/-)/Patched(+/-)双基因敲除鼠的构建
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作者 辛世杰 李璇 +1 位作者 Molly Duman-Scheel Wei Du 《中华医学杂志》 CAS CSCD 北大核心 2008年第3期185-188,共4页
目的构建CycD(-/-)/Ptc(+/-)双基因敲除鼠以验证Hh传导系统与Rb系统的关系。方法应用已有的杂合子CycD基因敲除鼠CycD(+/-)与杂合子Ptc基因敲除鼠Ptc(+/-)进行交配繁殖,得到双基因杂合子敲除鼠CycD(+/-)/Ptc(+... 目的构建CycD(-/-)/Ptc(+/-)双基因敲除鼠以验证Hh传导系统与Rb系统的关系。方法应用已有的杂合子CycD基因敲除鼠CycD(+/-)与杂合子Ptc基因敲除鼠Ptc(+/-)进行交配繁殖,得到双基因杂合子敲除鼠CycD(+/-)/Ptc(+/-),再利用该双基因杂合子敲除鼠进行二次交配繁殖,得到实验组CycD(-/-)/Ptc(+/-)双基因敲除鼠。结果实验得到了双基因敲除鼠CycD(-/-)/Ptc(+/-)、双基因杂合子基因敲除鼠CycD(+/-)/Ptc(+/-)、CycD单基因敲除鼠CycD(-/-)/Ptc(+/+)。结论通过本实验方法得到CycD(-/-)/Ptc(+/-)双基因敲除鼠,可用于进一步揭示Ptc基因与CycD基因相互影响调控的作用及Hedgehog与Rb信号传导通路在哺乳动物中的相关性。 展开更多
关键词 CYCLIN D patched 基因敲除鼠
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基于多尺度Patch与卷积交互的电缆温度预测模型
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作者 王婷婷 李廷顺 +2 位作者 谭文 吕博 陈翼轩 《计算机应用》 北大核心 2026年第1期314-321,共8页
高压电缆长期过热可能导致绝缘热击穿,进而影响电网的稳定性。然而,当前研究主要集中在传统预测模型上,忽略了温度数据的复杂性和动态特征。为了解决此问题,提出一种基于多尺度Patch与卷积交互的电缆温度预测模型(MSP-CI)。首先,采用通... 高压电缆长期过热可能导致绝缘热击穿,进而影响电网的稳定性。然而,当前研究主要集中在传统预测模型上,忽略了温度数据的复杂性和动态特征。为了解决此问题,提出一种基于多尺度Patch与卷积交互的电缆温度预测模型(MSP-CI)。首先,采用通道重组采样方法降低输入维度,并构建多尺度Patch分支结构,以实现复杂时间序列的解耦;其次,结合序列分解与卷积交互策略,分别提取粗粒度Patch的宏观信息与细粒度Patch的微观信息;最后,构建注意力融合模块,以动态平衡宏观与微观信息的权重,并得到最终的预测结果。在真实高压电缆温度数据集上的实验结果表明,MSP-CI相较于TimeMixer、PatchTST(Patch Time Series Transformer)和MSGNet(Multi-Scale interseries Graph Network)等基线模型,在均方误差(MSE)上下降了7.02%~34.87%,在平均绝对误差(MAE)上下降了5.15%~32.04%。可见,MSP-CI能有效提升电缆温度预测的准确率,为电力调度运行提供依据。 展开更多
关键词 高压电缆 温度预测 多尺度 PATCH 卷积交互
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CONSERVATION OF THREE-POINT COMPACT SCHEMES ON SINGLE AND MULTIBLOCK PATCHED GRIDS FOR HYPERBOLIC PROBLEMS 被引量:1
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作者 Zi-niu Wu (Department of Engineering Mechanics, Tsinghua University, Beijing 100084, China) 《Journal of Computational Mathematics》 SCIE CSCD 2003年第3期383-400,共18页
For nonlinear hyperbolic problems, conservation of the numerical scheme is important for convergence to the correct weak solutions. In this paper the conservation of the well-known compact scheme up to fourth order of... For nonlinear hyperbolic problems, conservation of the numerical scheme is important for convergence to the correct weak solutions. In this paper the conservation of the well-known compact scheme up to fourth order of accuracy on a single and uniform grid is studied, and a conservative interface treatment is derived for compact schemes on patched grids. For a pure initial value problem, the compact scheme is shown to be equivalent to a scheme in the usual conservative form. For the case of a mixed initial boundary value problem, the compact scheme is conservative only if the rounding errors are small enough. For a patched grid interface, a conservative interface condition useful for mesh refinement and for parallel computation is derived and its order of local accuracy is analyzed. 展开更多
关键词 CONSERVATION Compact scheme Uniform grid Multiblock patched grid.
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A Hierarchical Short Microneedle-Cupping Dual-Amplified Patch Enables Accelerated,Uniform,Pain-Free Transdermal Delivery of Extracellular Vesicles 被引量:1
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作者 Minwoo Song Minji Ha +8 位作者 Sol Shin Minjin Kim Soyoung Son Jihyun Lee Gui Won Hwang Jeongyun Kim Van Hieu Duong Jae Hyung Park Changhyun Pang 《Nano-Micro Letters》 2026年第1期268-289,共22页
Microneedles(MNs)have been extensively investigated for transdermal delivery of large-sized drugs,including proteins,nucleic acids,and even extracellular vesicles(EVs).However,for their sufficient skin penetration,con... Microneedles(MNs)have been extensively investigated for transdermal delivery of large-sized drugs,including proteins,nucleic acids,and even extracellular vesicles(EVs).However,for their sufficient skin penetration,conventional MNs employ long needles(≥600μm),leading to pain and skin irritation.Moreover,it is critical to stably apply MNs against complex skin surfaces for uniform nanoscale drug delivery.Herein,a dually amplified transdermal patch(MN@EV/SC)is developed as the stem cell-derived EV delivery platform by hierarchically integrating an octopusinspired suction cup(SC)with short MNs(≤300μm).While leveraging the suction effect to induce nanoscale deformation of the stratum corneum,MN@EV/SC minimizes skin damage and enhances the adhesion of MNs,allowing EV to penetrate deeper into the dermis.When MNs of various lengths are applied to mouse skin,the short MNs can elicit comparable corticosterone release to chemical adhesives,whereas long MNs induce a prompt stress response.MN@EV/SC can achieve a remarkable penetration depth(290μm)for EV,compared to that of MN alone(111μm).Consequently,MN@EV/SC facilitates the revitalization of fibroblasts and enhances collagen synthesis in middle-aged mice.Overall,MN@EV/SC exhibits the potential for skin regeneration by modulating the dermal microenvironment and ensuring patient comfort. 展开更多
关键词 Biomimetics CUPPING MICRONEEDLE Transdermal patch Extracellular vesicles
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Plant patch size,not number,determines vegetation recovery in mildly degraded Bangor alpine steppes under grazing exclusion
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作者 NIU Haishan LIU Min +6 位作者 ZHANG Jing KONG Qian LI Runfu ZHU Chuanlu CUI Xiaoyong WANG Shiping WANG Yanfen 《Journal of Mountain Science》 2026年第1期67-80,共14页
The alpine grassland vegetation on the Qinghai-Tibet Plateau is composed of plant patches in varied sizes.It remains uncertain whether vegetation recovery following grazing exclusion(GE)in degraded grasslands is drive... The alpine grassland vegetation on the Qinghai-Tibet Plateau is composed of plant patches in varied sizes.It remains uncertain whether vegetation recovery following grazing exclusion(GE)in degraded grasslands is driven by increases in patches number(NP),patch size(PS),or both.We based our predictions on two hypotheses:GE intensifies plant competition,and facilitation prevails near patches while competition prevails in interpatch spaces.We predicted that the NP would remain stable or decrease and PS would increase under GE treatment.To evaluate these predictions,we conducted a study in six lightly degraded alpine grasslands under free grazing(FG)conditions in Bangor County,Xizang Autonomous Region,China,with corresponding GE treatments using transects in 2017 and 2018.Results revealed that four sites in 2017 and five sites in 2018 had reduced NP and increased PS,with probabilities of 0.033(2017)and 0.004(2018),respectively,and a joint probability of 0.0001 under the null hypothesis that GE does not affect NP or PS.The NP reduction was solely due to the decrease in small patch sizes.An increase in PS was common across species,and a predominant tendency for NP reduction was observed among species across the sites.The overall changes in NP and PS were primarily driven by the three most abundant species(contributing more than 60%in both years),rather than by shifts in floristic composition.Our findings highlight that vegetation recovery in Bangor alpine steppes following GE relies solely on the expansion of existing patches rather than the recruitment of new ones in interpatch gaps.We recommend prioritizing growth-promoting measures,such as nutrient or water management,over seed addition when assisting with GE for restoring lightly degraded grasslands. 展开更多
关键词 Plant patches Stipa purpurea Patch size Grazing exclusion Degraded restoration
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广西沙化土地景观格局十年变化特征分析
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作者 莫奇京 罗蔚生 +3 位作者 徐占勇 柳雄辉 唐秋月 谭必增 《中南林业调查规划》 2026年第1期63-71,共9页
基于广西2014年、2019年和2023年沙化监测数据,综合运用Patch Analyst、Fragstats景观格局指数计算软件、景观生态学理论及马尔可夫转移矩阵方法,将沙化区域土地利用类型划分为耕地、林地等6个景观类型,从整体景观水平与景观类型水平分... 基于广西2014年、2019年和2023年沙化监测数据,综合运用Patch Analyst、Fragstats景观格局指数计算软件、景观生态学理论及马尔可夫转移矩阵方法,将沙化区域土地利用类型划分为耕地、林地等6个景观类型,从整体景观水平与景观类型水平分析其十年变化特征。结果显示:1)景观类型结构呈“剧烈调整-稳定微调”的阶段特征。2014—2019年,耕地占比从56.29%降至44.48%,林地、建设用地占比分别上升4.96%、3.60%;2019—2023年各景观类型占比波动均小于0.3%,最终形成“耕地相对主导、林地跟进、建设用地崛起”的多元格局,生态修复成效显现。2)景观破碎化集中在2014—2019年。景观水平上,斑块数量由9268个增至120314个,平均斑块面积从25.22 hm^(2)降至1.94 hm^(2);类型水平上,各景观平均斑块面积降幅为84.2%~90.9%。人类活动是导致该阶段景观破碎化的主要因素,2019年后破碎化格局趋于稳定。3)景观类型转移在2014—2019年较为活跃、2019—2023年趋于稳定,生态修复、城镇化、土地开发为三大核心驱动因素。 展开更多
关键词 沙化 景观格局 FRAGSTATS Patch Analyst 广西
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Engineering a Bilayered Scaffold as a Potential Cardiac Patch:From Scaffold Design to In Vitro Assessment
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作者 Adile Yuruk Ayhan Duzler +1 位作者 Sevil Dincer Isoglu Ismail Alper Isoglu 《Journal of Bionic Engineering》 2026年第1期394-415,共22页
In this study,we developed a novel bilayered scaffold consisting of a bottom layer composed of the Decellularized Bovine Pericardium(DP)coated with Polyaniline Nanoparticles(PANINPs)and a top layer made of an electros... In this study,we developed a novel bilayered scaffold consisting of a bottom layer composed of the Decellularized Bovine Pericardium(DP)coated with Polyaniline Nanoparticles(PANINPs)and a top layer made of an electrospun Poly(lactic-co-glycolic acid)/Gelatin(PLGA/Gel)membrane incorporated with Vascular Endothelial Growth Fac-tor(VEGF)and hawthorn extract.Functionally,the DP supplies native Extracellular Matrix(ECM)components and mechanical support,while PANINPs provide conductivity.The electrospun PLGA/Gel layer mimics fibrous ECM.It incorporates bioactives,with VEGF promoting pro-angiogenic stimulation and hawthorn extract enhanc-ing anticoagulant activity,as well as increasing surface hydrophilicity.The tissue adhesive ensures the interfacial integrity between the two layers.Decellularization efficiency was confirmed histologically using 4',6-diamidino-2-phenylindole(DAPI)and Hematoxylin-Eosin(H&E)staining.The DP exhibited a DNA content of 115.9±47.8 ng/mg DNA,compared to 982.88±395.42 ng/mg in Native Pericardium(NP).The PANINPs had an average par-ticle size of 104.94±13.7 nm.The conductivity of PANINPs-coated decellularized pericardium was measured to be 9.093±8.6×10-4 S/cm using the four-point probe method.PLGA/Gel membranes containing hawthorn extract(1%,5%,10%,and 15%w/v)and VEGF(0.1μg/mL,0.5μg/mL,and 1μg/mL)were fabricated by electrospinning,result-ing in fiber diameters between 850 and 1200 nm and pore sizes between 14 and 20μm.The anticoagulant efficiency of the membranes containing hawthorn extract reached 430 s in the Activated Partial Thromboplastin Time Assay(aPTT).Mechanical testing revealed a tensile strength of 22.70±6.33 MPa,an elongation of 53.58±10.63%,and Young's modulus of 0.67±0.10 MPa.The scaffold also exhibited over 91%cell viability and excellent cardiomyo-cyte adhesion.The hemolysis ratio was determined to be 0.421±0.191%,which confirms its blood compatibility.Our results indicate that the proposed bilayered scaffold can be a promising candidate for cardiac patch applications. 展开更多
关键词 Cardiac patch Bilayered scaffold DECELLULARIZATION ELECTROSPINNING Hawthorn extract VEGF
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