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Deep Transfers of p-Class Tower Groups
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作者 Daniel C. Mayer 《Journal of Applied Mathematics and Physics》 2018年第1期36-50,共15页
Let p be a prime. For any finite p-group G, the deep transfers T H,G ' : H / H ' → G ' / G " from the maximal subgroups H of index (G:H) = p in G to the derived subgroup G ' are introduced as an ... Let p be a prime. For any finite p-group G, the deep transfers T H,G ' : H / H ' → G ' / G " from the maximal subgroups H of index (G:H) = p in G to the derived subgroup G ' are introduced as an innovative tool for identifying G uniquely by means of the family of kernels ùd(G) =(ker(T H,G ')) (G: H) = p. For all finite 3-groups G of coclass cc(G) = 1, the family ùd(G) is determined explicitly. The results are applied to the Galois groups G =Gal(F3 (∞)/ F) of the Hilbert 3-class towers of all real quadratic fields F = Q(√d) with fundamental discriminants d > 1, 3-class group Cl3(F) □ C3 × C3, and total 3-principalization in each of their four unramified cyclic cubic extensions E/F. A systematic statistical evaluation is given for the complete range 1 d 7, and a few exceptional cases are pointed out for 1 d 8. 展开更多
关键词 Hilbert p-Class Field Towers p-Class GROUpS p-principalization Quadratic FIELDS Dihedral FIELDS of Degree 2p Finite p-Groups Two-Step Centralizers polarization pRINCIpLE Descendant Trees p-Group Generation Algorithm p-Multiplicator RANK Relation RANK Generator RANK Deep Transfers Shallow Transfers partial Order and Monotony pRINCIpLE of Artin patterns parametrized polycyclic pc-presentations Commutator Calculus
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Successive Approximation of p-Class Towers
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作者 Daniel C. Mayer 《Advances in Pure Mathematics》 2017年第12期660-685,共26页
Let F be a number field and p be a prime. In the successive approximation theorem, we prove that, for each integer n ≥ 1, finitely many candidates for the Galois group of the nth stage of the p-class tower over F are... Let F be a number field and p be a prime. In the successive approximation theorem, we prove that, for each integer n ≥ 1, finitely many candidates for the Galois group of the nth stage of the p-class tower over F are determined by abelian type invariants of p-class groups C1pE of unramified extensions E/F with degree [E : F] = pn-1. Illustrated by the most extensive numerical results available currently, the transfer kernels (TE, F) of the p-class extensions TE, F : C1pF → C1pE from F to unramified cyclic degree-p extensions E/F are shown to be capable of narrowing down the number of contestants significantly. By determining the isomorphism type of the maximal subgroups S G of all 3-groups G with coclass cc(G) = 1, and establishing a general theorem on the connection between the p-class towers of a number field F and of an unramified abelian p-extension E/F, we are able to provide a theoretical proof of the realization of certain 3-groups S with maximal class by 3-tower groups of dihedral fields E with degree 6, which could not be realized up to now. 展开更多
关键词 p-Class TOWERS Galois GROUpS Second p-Class GROUpS Abelian Type Invariants of p-Class GROUpS p-Transfer Kernel Types Artin Limit pattern Quadratic FIELDS Unramified Cyclic Extensions of Degree p Dihedral FIELDS of Degree 2p Finite p-Groups MAXIMAL Nilpotency CLASS MAXIMAL Subgroups polycyclic pc-presentations Commutator Calculus Central Series
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基于UPLC-QTRAP^(■)/MS^(2)方法评价不同干燥方式对益母草中化学成分的影响 被引量:21
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作者 谭亚杰 濮宗进 +9 位作者 唐于平 严辉 郭盛 朱振华 乐世俊 陈艳琰 彭国平 黄胜良 周桂生 段金廒 《中草药》 CAS CSCD 北大核心 2019年第7期1576-1586,共11页
目的通过多种化学成分的含量变化,评价晒干、阴干、红外干燥(50、60、70、80℃)、微波干燥(50、60、70、80、100℃)和热风干燥(50、60、70、80℃)等15种干燥方法对益母草药材品质的影响,并优选出适宜的益母草产地加工方法。方法运用UPLC... 目的通过多种化学成分的含量变化,评价晒干、阴干、红外干燥(50、60、70、80℃)、微波干燥(50、60、70、80、100℃)和热风干燥(50、60、70、80℃)等15种干燥方法对益母草药材品质的影响,并优选出适宜的益母草产地加工方法。方法运用UPLC-QTRAP?/MS2法测定益母草中3个生物碱类成分(盐酸水苏碱、盐酸益母草碱、葫芦巴碱)、4个酚酸类成分(苯甲酸、对羟基苯甲酸、香草酸、丁香酸)、5个苯丙素类成分(红景天苷、毛蕊花糖苷、绿原酸、咖啡酸、阿魏酸)、11个黄酮类成分(芦丁、异槲皮苷、金丝桃苷、汉黄芩素、山柰酚-3-O-芸香糖苷、芫花素、芹菜素、山柰酚、异鼠李素、橙皮素、槲皮素)和1个环烯醚萜苷类成分(益母草苷)的含量变化。结合主成分分析(PCA)和逼近理想值排序法(TOPSIS),综合评价不同干燥方式得到的益母草样品的品质。结果不同干燥方式对益母草中24个化学成分的含量影响显著,基于此进行PCA并将15种干燥方法分为3类;另外采用TOPSIS法对15种干燥方法进行评分,前3位为热风70℃、热风60℃和微波100℃干燥,都在很大程度上保留了益母草中活性成分。结论结合实践,优选热风70℃干燥为益母草产地加工工艺,为益母草的品质提供保障,为全国益母草生产加工提供科学依据。 展开更多
关键词 UpLC-QTRAp^(■)/MS^(2) TOpSIS法 绿 -3-O-
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Theory of pleiotropic action of biologically active compounds and medicines—Basic principles and practical application
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作者 N. A. Bizunok 《Open Journal of Clinical Diagnostics》 2013年第3期94-104,共11页
This article represents the main positions of the theory of pleiotropic action of biologically active compounds (BACs) and medicines, which has been designed by the author based on her own experimental researches. The... This article represents the main positions of the theory of pleiotropic action of biologically active compounds (BACs) and medicines, which has been designed by the author based on her own experimental researches. The term “pleiotropy” means the ability of the BACs and medicines to implement more than one mechanism of action resulting in the specific biological (pharmacological) effect. The interaction of these mechanisms forms a distinct pattern of biological response (pleiotropic pattern), which reflects the change in his character with the increased dose (concentration)-dependent efficacy of BACs and medicines. The article consists of description of different pleiotropic patterns established in experiments on the model of reactive oxygen species (ROS) generation by macrophages dependent on activity of specialized enzyme called Nox2-NAD(P)H oxidase (Nox2, EC 1.6.3.1). Moreover, it consists of explanation of pharmacodynamic nature of pleiotropic patterns by means of application Chou-Talalay median effect equalization and combination index (CI) theory. The novel theory explains unsolved until now universal aspects of activity BACs and medicines, such as slope angles of “dose-effect” dependences in the conditions relevant in vivo, and it is of fundamental interest. However, it has applications in experimental pharmacology, as it allows defining the choice of the individual compounds and combinations, modulating the trust effect selectively and efficiently. This knowledge opens up new approaches to medicines discovery and evaluation, their rational dosing and combining. 展开更多
关键词 Reactive Oxygen Species (ROS) Nox2-NAD(p)H Oxidase (Nox2) Slope Angles of DOSE-EFFECT DEpENDENCES pLEIOTROpY pLEIOTROpIC patterns polytropism pharmacological Affect Nature MEDICINES Combinations Novel THEORY of Biologically Active Compounds (BACs) and MEDICINES Action
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Co-Periodicity Isomorphisms between Forests of Finite <I>p</I>-Groups
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作者 Daniel C. Mayer 《Advances in Pure Mathematics》 2018年第1期77-140,共64页
Based on a general theory of descendant trees of finite p-groups and the virtual periodicity isomorphisms between the branches of a coclass subtree, the behavior of algebraic invariants of the tree vertices and their ... Based on a general theory of descendant trees of finite p-groups and the virtual periodicity isomorphisms between the branches of a coclass subtree, the behavior of algebraic invariants of the tree vertices and their automorphism groups under these isomorphisms is described with simple transformation laws. For the tree of finite 3-groups with elementary bicyclic commutator qu-otient, the information content of each coclass subtree with metabelian main-line is shown to be finite. As a striking novelty in this paper, evidence is provided of co-periodicity isomorphisms between coclass forests which reduce the information content of the entire metabelian skeleton and a significant part of non-metabelian vertices to a finite amount of data. 展开更多
关键词 FINITE p-Groups Descendant Trees pro-p GROUpS Coclass FORESTS Generator RANK Relation RANK Nuclear RANK parametrized polycyclic pc-presentations Automorphism GROUpS Central Series Two-Step Centralizers Commutator Calculus Transfer Kernels Abelian Quotient Invariants p-Group Generation Algorithm
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Expression of p27Kip1, A Cell Cycle Repressor Protein with Dual Roles for Both Cancer Prevention and Promotion, Is Regulated Primarily at the Level of Unusual p27Kip1 mRNA—A Short Concept Proposal 被引量:2
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作者 Isao Eto 《American Journal of Molecular Biology》 2018年第3期186-193,共8页
The p27Kip1 is a cell cycle repressor protein that regulates primarily the cell cycle transition from G1 to S phase and hence the DNA replication is in the S phase and cell division in the M phase. Expression of p27Ki... The p27Kip1 is a cell cycle repressor protein that regulates primarily the cell cycle transition from G1 to S phase and hence the DNA replication is in the S phase and cell division in the M phase. Expression of p27Kip1 protein has dual roles for both cancer prevention and promotion. For example, numerous nutritional and chemopreventive anti-cancer agents specifically increase the expression of p27Kip1 protein without directly affecting the expression of any other cell cycle regulatory proteins. On the other hand, pro-cancer agents (like glucose, insulin and other growth factors frequently seen in obesity and/or diabetes) specifically decrease the expression of p27Kip1 protein without directly affecting the expression of any other cell cycle regulatory proteins. Unlike expression of any other cell cycle regulatory proteins, expression of p27Kip1 protein is very unusual. The mRNA of p27Kip1 has a very long and unusual 5’-untranslated region (from -575 to -1 in human). It appears that the 5’-untranslated region of p27Kip1 mRNA forms two alternative secondary structures. One increases the expression of p27Kip1 protein when anti-cancer agents are added and another decrease the expression of p27K1p1 when pro-cancer agents are added. For this short concept proposal, Dr. Albert Einstein’s “visualized thought experiments (German: Gedanken experiment)” were used as a fundamental tool for understanding how either anti- or pro-cancer agents bring the primary structure of the 5’-untranslated region of p27Kip1 mRNA into two alternative secondary structures, thereby either increasing or decreasing, respectively, the translation initiation of p27Kip1 protein. 展开更多
关键词 p27KIp1 Cell Cycle Repressor protein CANCER prevention Anti-Cancer AGENTS CANCER pROMOTION pro-Cancer AGENTS p27KIp1 MRNA 5-prime-Untranslated Region Translation Initiation 5-prime Cap Upstream Open Reading Frame Internal Ribosome Entry Site
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鼻息肉上皮中血管活性肠肽和P物质表达的初步研究 被引量:2
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作者 薛刚 吴靖芳 +2 位作者 尚小领 林彦涛 成日青 《河北北方学院学报(医学版)》 2005年第1期4-6,共3页
目的:探讨人鼻息肉组织中SP和VIP的表达及意义。方法:采用HE染色、PAS染色和免疫组化方法检测人鼻息肉组织的病理变化及SP和VIP表达。结果:鼻息肉黏膜均有不同程度的改变,实验组与对照组相比基膜明显增厚(P <0 .0 1) ;A、C组差别显著... 目的:探讨人鼻息肉组织中SP和VIP的表达及意义。方法:采用HE染色、PAS染色和免疫组化方法检测人鼻息肉组织的病理变化及SP和VIP表达。结果:鼻息肉黏膜均有不同程度的改变,实验组与对照组相比基膜明显增厚(P <0 .0 1) ;A、C组差别显著(P <0 .0 5 )。实验组黏液腺面积与对照组相比差别显著(P <0 .0 1)。SP和VIP免疫反应阳性结构均呈棕黄色,二者在实验组与对照组分布相似。SP阳性纤维分布于血管、腺体周围,可见散在的圆形或椭圆型阳性细胞,部分黏膜下腺体上皮细胞也呈SP阳性;但实验组阳性纤维和细胞明显稀疏。VIP阳性纤维和细胞位于黏膜腺体、血管周围以及部分黏膜上皮和黏膜下腺上皮细胞胞质中,但实验组中VIP阳性纤维着色较深,密度增加。结论:SP和VIP在鼻息肉形成中具有重要的作用。 展开更多
关键词 p物质 VIp HE Sp pAS
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Transplantation of human hepatocytes into tolerized genetically immunocompetent rats 被引量:23
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作者 EdwinC.Ouyang CatherineH.Wu +2 位作者 CherieWalton KittichaiPromrat GeorgeY.Wu 《World Journal of Gastroenterology》 SCIE CAS CSCD 2001年第3期324-330,共7页
AIM: To determine whether normal genetically immunocompetent rodent hosts could be manipulated to accept human hepatocyte transplants with long term survival without immunosuppression. METHODS: Tolerance towards human... AIM: To determine whether normal genetically immunocompetent rodent hosts could be manipulated to accept human hepatocyte transplants with long term survival without immunosuppression. METHODS: Tolerance towards human hepatocytes was established by injection of primary human hepatocytes or Huh7 human hepatoma cells into the peritoneal cavities of fetal rats. Corresponding cells were subsequently transplanted into newborn rats via intrasplenic injection within 24h after birth. RESULTS: Mixed lymphocyte assays showed that spleen cells from non-tolerized rats were stimulated to proliferate when exposed to human hepatocytes, while cells from tolerized rats were not. Injections made between 15 d and 17 d of gestation produced optimal tolerization. Transplanted human hepatocytes in rat livers were visualized by immunohistochemical staining of human albumin. By dot blotting of genomic DNA in livers of tolerized rats 16 weeks after hepatocyte transplantation, it was found that approximately 2.5 X 10(5) human hepatocytes survived per rat liver. Human albumin mRNA was detected in rat livers by RT-PCR for 15 wk, and human albumin protein was also detectable in rat serum. CONCLUSION: Tolerization of an immuno-competent rat can permit transplantation, and survival of functional human hepatocytes. 展开更多
关键词 ALBUMINS Animals Cell Line Transformed Disease Models Animal Female Gene Expression Graft Survival Hepatitis HEpATOBLASTOMA Hepatocytes Humans Immune Tolerance IMMUNOCOMpETENCE Liver Liver Neoplasms Lymphocyte Culture Test Mixed Microscopy Confocal pregnancy RNA Messenger RATS Rats Sprague-Dawley Research Support Non-U.S. Gov't Research Support U.S. Gov't p.H.S.
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P-gp、GST-Л、TOPO在肺癌中的表达及意义 被引量:5
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作者 李凡彩 周英琼 +1 位作者 侯巧燕 陆明深 《华夏医学》 2005年第1期1-5,共5页
目的 :探讨多药耐药基因 (MDR)产物在肺癌组织中的表达及其相互关系。方法 :采用免疫组化 S- P方法检测 6 0例肺癌组织中 MDR基因产物 (P- gp、GST-Л和 TOPO )的表达情况。结果 :1肺癌组织中的 P- gp、GST-Л和 TOPO 阳性表达率分别为 ... 目的 :探讨多药耐药基因 (MDR)产物在肺癌组织中的表达及其相互关系。方法 :采用免疫组化 S- P方法检测 6 0例肺癌组织中 MDR基因产物 (P- gp、GST-Л和 TOPO )的表达情况。结果 :1肺癌组织中的 P- gp、GST-Л和 TOPO 阳性表达率分别为 6 3.3%、6 6 .7%和 5 0 .0 %。GST- Л和 P- gp在非小细胞肺癌 (NSCL C)中的表达率分别为 75 %和70 .8% ,在小细胞肺癌 (SCL C)中的表达率均为 14 .3% ,两者比较均有显著性差异 (P<0 .0 5 )。GST- Л和 P- gp在腺癌的表达明显高于鳞癌 (P<0 .0 1) ;TOPO 在腺癌组的表达率明显低于鳞状细胞癌组和小细胞癌组 (P<0 .0 5 )。 2两种或两种以上 MDR基因产物的共表达率为 80 % ,明显高于单独基因的表达率 11.7% (P- gp)和 13.3% (TOPO )。GST-Л表达均伴有 P- gp和 /或 TOPO 的表达 ;P- g P表达和 GST-Л表达呈明显正相关 (P<0 .0 1)。 TOPO 表达与P- gp、GST- Л表达均呈显著负相关 (P<0 .0 1)。结论 :P- gp、GST- Л和 TOPO 在肺癌组织中的表达对肿瘤的耐药起重要作用 ,单基因和多基因协同作用 ,以多基因共表达作用为主。 展开更多
关键词 GST-Л TOpOⅡ p-Gp (NSCLC) (SCLC) p-Gp表达 S-p方法 MDR
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阿尔金淡水泉早古生代泥质高压麻粒岩及其P-T演化轨迹 被引量:39
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作者 曹玉亭 刘良 +2 位作者 王超 陈丹玲 张安达 《岩石学报》 SCIE EI CAS CSCD 北大核心 2009年第9期2260-2270,共11页
南阿尔金构造带淡水泉一带出露的含石榴石蓝晶石黑云母片麻岩是一套典型的泥质高压麻粒岩,其峰期特征矿物组合为石榴子石+蓝晶石+钾长石+金红石+石英。根据矿物内部一致性热力学数据和Thermocalc 3.23程序计算,确定其峰期变质温压条件为... 南阿尔金构造带淡水泉一带出露的含石榴石蓝晶石黑云母片麻岩是一套典型的泥质高压麻粒岩,其峰期特征矿物组合为石榴子石+蓝晶石+钾长石+金红石+石英。根据矿物内部一致性热力学数据和Thermocalc 3.23程序计算,确定其峰期变质温压条件为T>850℃和P>11kbar。结合岩相学研究和P-T视剖面图计算,可识别出该岩石经历了4个阶段的变质演化,构成了一个早期快速等温降压,后期近等压降温的顺时针型的退变质P-T演化轨迹,为与陆壳俯冲碰撞有关的高压变质事件的产物。该岩石锆石阴极发光图像显示其内部具有明显的核-边结构,核部为残留的原岩碎屑锆石,边部则表现为面状或扇状生长的变质锆石的特征。微区原位LA-ICP-Ms微量元素分析表明,核部测点的重稀土含量较高,对应Th/U接近于0.4,具有岩浆锆石的特征;边部测点的重稀土相对亏损,重稀土配分曲线平坦,对应Th/U比值均小于0.1,显示与石榴子石平衡共生的变质锆石特征。LA-ICP-MS微区定年获得其变质年龄为486±5Ma,该年龄值与阿尔金江尕勒萨依和英格利萨依两地超高压变质岩石的变质年龄相近,进一步证明沿阿尔金构造带南缘断续存在一条早古生代的高压-超高压变质岩带。另外,本次研究在获得该泥质高压麻粒岩峰期变质时代的同时,还获得该岩石原岩的形成时代上限值约为719Ma,从而限定阿尔金构造带南缘阿尔金群的形成时代可能不属古元古代,而应属新元古代。 展开更多
关键词 Altyn Tagh area metamorphic age mineral assemblage internal structure pelitic GRANULITE rapid EXHUMATION
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3株致病性鸡大肠杆菌P型菌毛结构基因的克隆、序列测定及同源性分析 被引量:1
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作者 苗玉和 王文成 张贵刚 《中国兽医学报》 CAS CSCD 北大核心 2005年第3期250-252,共3页
用鸡致病性大肠杆菌分离株O1、O2和O78的基因组DNA做为模板,PCR分别扩增出了0.55kb的P型菌毛结构基因(papA)。将扩增得到的3个papA基因片段分别克隆进pGEM-T○R载体中,转化至受体菌JM109中,用Amp/IPTG/X-gal琼脂平板蓝白菌落筛选法,得... 用鸡致病性大肠杆菌分离株O1、O2和O78的基因组DNA做为模板,PCR分别扩增出了0.55kb的P型菌毛结构基因(papA)。将扩增得到的3个papA基因片段分别克隆进pGEM-T○R载体中,转化至受体菌JM109中,用Amp/IPTG/X-gal琼脂平板蓝白菌落筛选法,得到含阳性重组子的菌株,提取质粒后用BamH和Sal双酶切进行鉴定。所得阳性重组子进行DNA序列测定,测序结果经DNAStar核酸分析软件包分析比较,结果表明,所构建的克隆质粒中均含有相应完整papA基因,其开放式阅读框架大小为549bp,编码182个氨基酸。此3株菌的P型菌毛结构基因的同源性为98.9%~100%,其中O1株和O78株的P型菌毛基因的ORF序列100%相同,O2株有2个碱基与前两者不同。 展开更多
关键词 p型菌毛 DNA DNA IpTG Star pCR Amp Sal
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Polydatin prevents the induction of secondary brain injury after traumatic brain injury by protecting neuronal mitochondria 被引量:17
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作者 Li Li Hong-Ping Tan +8 位作者 Cheng-Yong Liu Lin-Tao Yu Da-Nian Wei Zi-Chen Zhang Kui Lu Ke-Sen Zhao Marc Maegele Dao-Zhang Cai Zheng-Tao Gu 《Neural Regeneration Research》 SCIE CAS CSCD 2019年第9期1573-1582,共10页
Polydatin is thought to protect mitochondria in different cell types in various diseases.Mitochondrial dysfunction is a major contributing factor in secondary brain injury resulting from traumatic brain injury.To inve... Polydatin is thought to protect mitochondria in different cell types in various diseases.Mitochondrial dysfunction is a major contributing factor in secondary brain injury resulting from traumatic brain injury.To investigate the protective effect of polydatin after traumatic brain injury,a rat brain injury model of lateral fluid percussion was established to mimic traumatic brain injury insults.Rat models were intraperitoneally injected with polydatin(30 mg/kg)or the SIRT1 activator SRT1720(20 mg/kg,as a positive control to polydatin).At 6 hours post-traumatic brain injury insults,western blot assay was used to detect the expression of SIRT1,endoplasmic reticulum stress related proteins and p38 phosphorylation in cerebral cortex on the injured side.Flow cytometry was used to analyze neuronal mitochondrial superoxide,mitochondrial membrane potential and mitochondrial permeability transition pore opened.Ultrastructural damage in neuronal mitochondria was measured by transmission electron microscopy.Our results showed that after treatment with polydatin,release of reactive oxygen species in neuronal mitochondria was markedly reduced;swelling of mitochondria was alleviated;mitochondrial membrane potential was maintained;mitochondrial permeability transition pore opened.Also endoplasmic reticulum stress related proteins were inhibited,including the activation of p-PERK,spliced XBP-1 and cleaved ATF6.SIRT1 expression and activity were increased;p38 phosphorylation and cleaved caspase-9/3 activation were inhibited.Neurological scores of treated rats were increased and the mortality was reduced compared with the rats only subjected to traumatic brain injury.These results indicated that polydatin protectrd rats from the consequences of traumatic brain injury and exerted a protective effect on neuronal mitochondria.The mechanisms may be linked to increased SIRT1 expression and activity,which inhibits the p38 phosphorylation-mediated mitochondrial apoptotic pathway.This study was approved by the Animal Care and Use Committee of the Southern Medical University,China(approval number:L2016113)on January 1,2016. 展开更多
关键词 nerve REGENERATION TRAUMATIC brain injury pOLYDATIN MITOCHONDRIA endoplasmic reticulum stress SIRT1 reactive oxygen species p38 MITOCHONDRIAL membrane potential MITOCHONDRIAL permeability transition pore lateral fluid pERCUSSION neural REGENERATION
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郯庐断裂带张八岭隆起南段肥东群石榴角闪岩变质P-T演化史对其构造属性的制约 被引量:21
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作者 石永红 朱光 王道轩 《岩石学报》 SCIE EI CAS CSCD 北大核心 2009年第12期3335-3345,共11页
通过对张八岭隆起南端肥东群中磁铁石榴铁闪石岩的岩相学、矿物成分分析和热力学评价,并结合野外地质填图和共生围岩分析表明,该岩石经历了5期变质作用,展现了顺时针的P-T演化特征,早期阶段表现为近等压升温,晚期阶段为降温降压的过程,... 通过对张八岭隆起南端肥东群中磁铁石榴铁闪石岩的岩相学、矿物成分分析和热力学评价,并结合野外地质填图和共生围岩分析表明,该岩石经历了5期变质作用,展现了顺时针的P-T演化特征,早期阶段表现为近等压升温,晚期阶段为降温降压的过程,其峰期变质平均P-T条件为:524℃和0.49GPa。结合地质背景和郯庐断裂带的演化特征分析,早期过程可能反映的扬子基底所经历的区域变质过程,晚期过程可能是由于郯庐断裂的后期抬升分量所致,不具有造山带的P-T演化特征。对比前人对宿松群的变质演化历史的研究,肥东群和宿松群峰期变质压力差可达0.8GPa,表明两者属于不同变质级别的块体。因而,肥东群和宿松群不能作为被郯庐断裂左行错开的标志层。由此表明,张八岭隆起南段所出露的肥东群变质杂岩,属于扬子板块上的变质基底,郯庐断裂带活动中将其剥露地表,并没有经历过大别造山带的变质作用。 展开更多
关键词 influence fault zone temperature and pRESSURE analysis late stage 宿 belong to southern TERRAIN peak pRESSURE
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HPLC特征图谱结合多模式识别及熵权TOPSIS法的不同基原蒲黄药材质量评价 被引量:9
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作者 田芳 张英 +2 位作者 吴孟华 曹晖 马志国 《中草药》 北大核心 2025年第4期1377-1384,共8页
目的建立蒲黄Typhae Pollen的特征图谱分析方法,结合熵权-优劣解距离(TOPSIS)法评价2种基原蒲黄质量,采用化学模式识别分析方法进一步明确2种基原蒲黄的质量差异标志物。方法采用HPLC法建立24批蒲黄不同基原药材的特征图谱,采用“中药... 目的建立蒲黄Typhae Pollen的特征图谱分析方法,结合熵权-优劣解距离(TOPSIS)法评价2种基原蒲黄质量,采用化学模式识别分析方法进一步明确2种基原蒲黄的质量差异标志物。方法采用HPLC法建立24批蒲黄不同基原药材的特征图谱,采用“中药色谱指纹图谱相似度评价系统”软件(2012版)确定2种基原蒲黄各自的共有峰及其基原之间交叉共有峰,均采用对照品进行色谱峰的指认。以峰面积为依据,采用熵权TOPSIS法计算相对贴近程度,得到2种基原蒲黄的综合质量排名及各特征峰的权重;同时,采用主成分分析(principal component analysis,PCA)、偏最小二乘法判别分析(partial least square discriminate analysis,PLS-DA)筛选并确认2种基原蒲黄的质量差异标志物。结果水烛香蒲、东方香蒲特征图谱分别指认并确定了13个特征峰和16个特征峰,其中峰8、9、12是东方香蒲的特有峰,峰7、11与峰13之间的相对峰高可直观区分2种基原蒲黄。特征图谱对比分析发现,东方香蒲的含量测定指标选择峰13(水仙苷)更为合理。熵权TOPSIS法结果表明,各基原蒲黄样品批次间的特征峰均可稳定传递,东方香蒲的相对贴近程度(C_(i))均高于水烛香蒲,说明2种基原蒲黄质量有差异。PCA提取出4个主成分,累积方差贡献率可达89.008%。PLS-DA筛选出山柰酚-3-O-芸香糖苷等9个质量差异标志物,其中山柰酚-3-O-芸香糖苷、异槲皮苷、异鼠李素-3-O-葡萄糖苷等7个质量差异标志物为首次提出。结论建立的分析方法可对2种基原蒲黄进行区分,并特异性识别两者的差异性成分,为蒲黄不同基原之间的区分鉴别及其质量控制提供依据。 展开更多
关键词 熵权TOpSIS法 -3-O-(2G-α-L-)- -3-O- -3-O-(2G-α-L-)- -3-O- -3-O- -3-O- -3-O-
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Immunotherapy of Cancer—A Historical Note
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作者 Istvan Berczi 《Journal of Cancer Therapy》 2014年第13期1186-1189,共4页
We examined the possibility that the anti-estrogens, tamoxifen (TX) and toremifen (TO) interacted?with the immune system. Indeed, both TX and TO stimulated cells mediated cytotoxicity reactions by various killer cells... We examined the possibility that the anti-estrogens, tamoxifen (TX) and toremifen (TO) interacted?with the immune system. Indeed, both TX and TO stimulated cells mediated cytotoxicity reactions by various killer cells: killer T (TK), natural killer (NK), lymphokine activated killer (LAK) cells. Both TX and TO inhibited the growth of tumors that express estrogen receptors. Thus these antiestrogens inhibited tumor growth and stimulated killer cells for cytotoxicty on such tumors. Therefore these agents were presumed to stimulate tumor immunity. We tested the P815 mouse mastcytoma with TK, LK, and TX or TO. A therapeutic effect was observed in both experiments. The SL2-5 murine lymphoma was tested with NK and TX cells or TO cells and successful immunotherapy was observed.?We digested human breast carcinomas and lung tumors with collagenase. The killer cells were separated from tumor cells on Ficoll gradients. TX and TO enhanced the cytotoxic effect of autologous killer cells on the corresponding tumor cells. This experiment indicates that the results obtained in animals are also valid for human malignant disease. 展开更多
关键词 Murine Tumors: p815 Masocytoma SL2-5 Lymphoma Human Cancers: Breast CARCINOMAS and Lung CARCINOMAS Tamoxifen Toremiphen Thymus-Derived Lymphocytes KILLER T CELLS (TK Cells) Natural KILLER CELLS (NK Cells) Lymhokine Activated KILLER CELLS (LAK Cells) Combination IMMUNOTHERApY of CANCER
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Long noncoding RNA GAS5 acts as a competitive endogenous RNA to regulate GSK-3β and PTEN expression by sponging miR-23b-3p in Alzheimer's disease
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作者 Li Zeng Kaiyue Zhao +5 位作者 Jianghong Liu Mimin Liu Zhongdi Cai Ting Sun Zhuorong Li Rui Liu 《Neural Regeneration Research》 2026年第1期392-405,共14页
Long noncoding RNA and microRNA are regulatory noncoding RNAs that are implicated in Alzheimer's disease, but the role of long noncoding RNA-associated competitive endogenous RNA has not been fully elucidated. The... Long noncoding RNA and microRNA are regulatory noncoding RNAs that are implicated in Alzheimer's disease, but the role of long noncoding RNA-associated competitive endogenous RNA has not been fully elucidated. The long noncoding RNA growth arrest-specific 5(GAS5) is a member of the 5′-terminal oligopyrimidine gene family that may be involved in neurological disorders, but its role in Alzheimer's disease remains unclear. This study aimed to investigate the function of GAS5 and construct a GAS5-associated competitive endogenous RNA network comprising potential targets. RNA sequencing results showed that GAS5 was upregulated in five familial Alzheimer's disease(5×FAD) mice, APPswe/PSEN1dE9(APP/PS1) mice, Alzheimer's disease-related APPswe cells, and serum from patients with Alzheimer's disease. Functional experiments with targeted overexpression and silencing demonstrated that GAS5 played a role in cognitive dysfunction and multiple Alzheimer's disease-associated pathologies, including tau hyperphosphorylation, amyloid-beta accumulation, and neuronal apoptosis. Mechanistic studies indicated that GAS5 acted as an endogenous sponge by competing for microRNA-23b-3p(miR-23b-3p) binding to regulate its targets glycogen synthase kinase 3beta(GSK-3β) and phosphatase and tensin homologue deleted on chromosome 10(PTEN) expression in an Argonaute 2-induced RNA silencing complex(RISC)-dependent manner. GAS5 inhibited miR-23b-3p-mediated GSK-3β and PTEN cascades with a feedforward PTEN/protein kinase B(Akt)/GSK-3β linkage. Furthermore, recovery of GAS5/miR-23b-3p/GSK-3β/PTEN pathways relieved Alzheimer's disease-like symptoms in vivo, indicated by the amelioration of spatial cognition, neuronal degeneration, amyloid-beta load, and tau phosphorylation. Together, these findings suggest that GAS5 promotes Alzheimer's disease pathogenesis. This study establishes the functional convergence of the GAS5/miR-23b-3p/GSK-3β/PTEN pathway on multiple pathologies, suggesting a candidate therapeutic target in Alzheimer's disease. 展开更多
关键词 Alzheimer's disease amyloid-beta peptide accumulation cognitive dysfunction competitive endogenous RNA glycogen synthase kinase 3beta lncRNA growth arrest-specific 5 microRNA-23b-3p neuronal apoptosis phosphatase and tensin homologue deleted on chromosome 10 tau phosphorylation
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The involvement of p38 MAPK in transforming growth factor β1-induced apoptosis in murine hepatocytes 被引量:15
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作者 LiaoJH ChenJS 《Cell Research》 SCIE CAS CSCD 2001年第2期89-94,共6页
We reported in this manuscript that TGF-beta1 induces apoptosis in AML12 murine hepatocytes, which is associated with the activation of p38 MAPK signaling pathway. SB202190, a specific inhibitor of p38 MAPK, strongly ... We reported in this manuscript that TGF-beta1 induces apoptosis in AML12 murine hepatocytes, which is associated with the activation of p38 MAPK signaling pathway. SB202190, a specific inhibitor of p38 MAPK, strongly inhibited the TGF-beta1-induced apoptosis and PAI-1 promoter activity. Treatment of cells with TGF-beta1 activates p38. Furthermore, over-expression of dominant negative mutant p38 also reduced the TGF-beta1-induced apoptosis. The data indicate that the activation of p38 is involved in TGF-beta1-mediated gene expression and apoptosis. 展开更多
关键词 Animals Apoptosis Cells Cultured DNA Fragmentation Enzyme Inhibitors Gene Expression Regulation Enzymologic Genes Reporter Genetic Vectors HEpATOCYTES IMIDAZOLES MAp Kinase Signaling System Mice Mitogen-Activated protein Kinases Mutation phosphorylation plasminogen Activator Inhibitor 1 pYRIDINES Research Support Non-U.S. Gov't TRANSFECTION Transforming Growth Factor beta p38 Mitogen-Activated protein Kinases
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肝炎后肝硬化患者血清TNF-α、BGP及尿Crosslaps变化与骨代谢的关系 被引量:1
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作者 陈自平 刘倩 +1 位作者 王文奇 闫明先 《山东医药》 CAS 北大核心 2005年第10期1-3,共3页
目的探讨肝炎后肝硬化患者骨代谢异常的发病机制。方法分别测定36例乙型肝炎后肝硬化患者血清TNF-α、骨钙素(BGP)、尿骨胶原交联(Crosslaps)水平及骨密度,并与15例健康者对照。结果肝硬化组血清肿瘤坏死因子α(TNF-α)、尿Crosslaps水... 目的探讨肝炎后肝硬化患者骨代谢异常的发病机制。方法分别测定36例乙型肝炎后肝硬化患者血清TNF-α、骨钙素(BGP)、尿骨胶原交联(Crosslaps)水平及骨密度,并与15例健康者对照。结果肝硬化组血清肿瘤坏死因子α(TNF-α)、尿Crosslaps水平较对照组显著升高(P<0.01,<0.05),其中骨质疏松(OP)组较非骨质疏松(NOP)组升高明显(P<0.01,<0.01),而肝硬化组血清BGP水平较对照组明显降低(P<0.01),其中OP组较NOP组降低更明显(P<0.05)。OP组血清TNF-α、尿Crosslaps均与尺桡骨密度呈负相关(r=-0.483,P<0.05;r=-0.624,P<0.01),而血清BGP与尺桡密度呈正相关(r=0.51,P<0.05)。结论乙肝后肝硬化患者存在骨形成减弱,骨吸收加强,从而导致肝性骨病(HBD)发生。血清TNF-α水平升高可引起骨吸收加强,是HBD发生的重要原因之一。降低体内TNF-α水平,对HBD防治可能有一定意义。 展开更多
关键词 尿Crosslaps TNF-α BGp α(TNF-α) 尿 0.05 HBD p水平 NOp
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反式二氢二醇环氧苯并芘诱发细胞p53基因的变化 被引量:1
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作者 黄勇 陈家堃 +3 位作者 吴中亮 吕嘉春 纪卫东 蒋义国 《毒理学杂志》 CAS CSCD 北大核心 2005年第2期99-101,共3页
目的 观察苯并(a)芘[B(a)P]代谢产物反式二氢二醇环氧苯并芘[anti 7,8, dihydrodiol 9,10 epoxidebenzo(a)pyrene ,BPDE]诱发的恶性转化的人支气管上皮细胞(humanbronchialepithelialcells ,HBE)及其裸鼠成瘤细胞中的p5 3基因突变情况... 目的 观察苯并(a)芘[B(a)P]代谢产物反式二氢二醇环氧苯并芘[anti 7,8, dihydrodiol 9,10 epoxidebenzo(a)pyrene ,BPDE]诱发的恶性转化的人支气管上皮细胞(humanbronchialepithelialcells ,HBE)及其裸鼠成瘤细胞中的p5 3基因突变情况,探讨BPDE诱导细胞癌变的机制。方法 多聚酶链聚合反应 单链构象多态性分析(PCR SSCP)、基因测序。结果 PCR SSCP分析结果提示,反式BPDE诱发的恶性转化细胞及其裸鼠成瘤细胞p5 3基因的Exon 7和Exon 8有突变。基因测序发现裸鼠成瘤细胞(B3 )的p5 3基因Exon 8的第2 82位密码子位置出现了一个G→T点突变,其编码的氨基酸由精氨酸(CGG)→亮氨酸(CTG)。结论 反式BPDE可诱导p5 3基因发生突变,提示p5 3基因突变可能是BPDE诱导细胞癌变的重要机制之一。 展开更多
关键词 p53基因突变 pCR-SSCp BpDE (a) cells
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奎硫平、利培酮对首发精神分裂症患者认知功能及P300的影响 被引量:9
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作者 王长虹 李晏 +3 位作者 刘旭 王来海 潘苗 穆俊林 《中国心理卫生杂志》 CSSCI CSCD 北大核心 2005年第5期333-336,共4页
目的:比较利培酮和奎硫平对首发精神分裂症患者认知功能的影响。方法:采用随机对照研究连续观察12周,利培酮组32例,剂量范围为1~7mg/d,奎硫平组35例,剂量范围25~750mg/d。进行PANSS、韦氏记忆量表(WMS)和事件相关电位P_(300)检查。结... 目的:比较利培酮和奎硫平对首发精神分裂症患者认知功能的影响。方法:采用随机对照研究连续观察12周,利培酮组32例,剂量范围为1~7mg/d,奎硫平组35例,剂量范围25~750mg/d。进行PANSS、韦氏记忆量表(WMS)和事件相关电位P_(300)检查。结果:首发精神分裂症患者的长时记忆、短时记忆、瞬时记忆及记忆商数(MQ)受损较为明显,与对照组比较差异有显著性(P<0.05)。P_(300)电位成分中P_2、N_2及P_3潜伏期明显延长,P_2及P_3波幅明显降低,与对照组比差异均有显著性(P<0.05)。经过12周治疗,奎硫平和利培酮组PANSS 总分、阳性症状分、阴性症状分及一般精神病理症状分均降低,两组相比差异无显著性(P>0.05),说明两药的疗效相当。服用奎硫平及利培酮治疗的患者WMS 的再认、联想、理解及记忆商(MQ)均明显高于治疗前,治疗后两组患者WMS 各项目之间比较差异均无显著性(P>0.05);两组在治疗前后P_(300)各指标之间差异无显著性。结论:首发精神分裂症患者存在着认知功能障碍,奎硫平与利培酮对改善首发精神分裂症认知功能的作用相当。 展开更多
关键词 pANSS p300检查 p300电位 p3潜伏期 p3波幅
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