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Energy Saving Cooperative Communication over Fading Channels with Relay Selection and Power Control 被引量:7
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作者 Wei Yifei Teng Yinglei +2 位作者 Wang Li Song Mei Man Yi 《China Communications》 SCIE CSCD 2012年第6期124-134,共11页
In order to save energy and make more efficient use of wireless channel, this article puts forward an energy saving cooperative relaying scheme which actuates the cooperative transmis- sion only when the feedback from... In order to save energy and make more efficient use of wireless channel, this article puts forward an energy saving cooperative relaying scheme which actuates the cooperative transmis- sion only when the feedback from the destination indicates failure of the direct transmission. The proposed scheme selects the optimal relay and its corresponding transmission power in each time slot based on channel condition and residual ener- gy with the objective of minimizing energy con- sumption and extending network lifetime. In the study, the f'mite-state Markov channel model is used to characterize the correlation structure of channel fading in wireless networks, and the pro- cedure of relay selection and transmission power decision is formulated as a M arkov decision process. Numerical and simulation results show that the proposed scheme consumes less energy and prolongs the network lifetime. 展开更多
关键词 energy saving relay selection POWERCONTROL coop erative communication
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Reputation-Based Hierarchically Cooperative Spectrum Sensing Scheme in Cognitive Radio Networks 被引量:3
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作者 CHEN Huifang XIE Lei NI Xiong 《China Communications》 SCIE CSCD 2014年第1期12-25,共14页
Cooperative spectrum sensing in cog- nitive radio is investigated to improve the det- ection performance of Primary User (PU). Meanwhile, cluster-based hierarchical coop- eration is introduced for reducing the overh... Cooperative spectrum sensing in cog- nitive radio is investigated to improve the det- ection performance of Primary User (PU). Meanwhile, cluster-based hierarchical coop- eration is introduced for reducing the overhead as well as maintaining a certain level of sens- ing performance. However, in existing hierar- chically cooperative spectrum sensing algo- rithms, the robustness problem of the system is seldom considered. In this paper, we pro- pose a reputation-based hierarchically coop- erative spectrum sensing scheme in Cognitive Radio Networks (CRNs). Before spectrum sensing, clusters are grouped based on the location correlation coefficients of Secondary Users (SUs). In the proposed scheme, there are two levels of cooperation, the first one is performed within a cluster and the second one is carried out among clusters. With the reputa- tion mechanism and modified MAJORITY rule in the second level cooperation, the pro- posed scheme can not only relieve the influ- ence of the shadowing, but also eliminate the impact of the PU emulation attack on a rela- tively large scale. Simulation results show that, in the scenarios with deep-shadowing or mul- tiple attacked SUs, our proposed scheme ach- ieves a better tradeoff between the system robustness and the energy saving compared with those conventionally cooperative sensing schemes. 展开更多
关键词 cognitive radio networks coop- erative spectrum sensing cluster location cor- relation REPUTATION
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STUDY ON CELL ORIGIN OF MALIGNANT LYMPHOPROLIFERATIVE DISORDERS WITH POLYMERASE CHAIN REACTION
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作者 王鲁群 《中国实验血液学杂志》 CAS CSCD 1995年第2期180-184,共5页
Genotype of IgH, TCRγ and TCR δ gene rearrangement in 42 cases of malignant lymphoproliferative disorders were studied by using polymerase chain reaction (PCR) technique. The results suggested that among the 23 case... Genotype of IgH, TCRγ and TCR δ gene rearrangement in 42 cases of malignant lymphoproliferative disorders were studied by using polymerase chain reaction (PCR) technique. The results suggested that among the 23 cases, in which malignant cells expressed B-lineage cell surface markers, 20 showed IgH gene rearrangement and 11 had TCRγ gene rearrangement and / or TCRδ gene deletion. All the 11 cases expressed T-lineage cell differentiation antigens were found to have TCRγand TCRδ gene rearrangement or deletion and only one had IgH gene rearrangement. Double rearrangements of IgH and TCRγ genes were detected in all the 3 cases of T and B double-phenotype ALL. In the cases malignant cells did not express any lineage specific antigens while 4/5 had TCRγ gene rearrangement but all failed in IgH gene rearrangement. The relation of cellular differentiation origin and rearrangement of antigen receptor genes with clinical manifestations was discussed. 展开更多
关键词 POLYMERASE CHAIN reaction gene REARRANGEMENT MALIGNANT lymphoprolif erative DISORDER
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Auxiliary Classifier of Generative Adversarial Network for Lung Cancer Diagnosis
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作者 P.S.Ramapraba P.Epsiba +1 位作者 K.Umapathy E.Sivanantham 《Intelligent Automation & Soft Computing》 SCIE 2023年第5期2177-2189,共13页
The classification of lung nodules is a challenging problem as the visual analysis of the nodules and non-nodules revealed homogenous textural patterns.In this work,an Auxiliary Classifier(AC)-Generative Adversarial Net... The classification of lung nodules is a challenging problem as the visual analysis of the nodules and non-nodules revealed homogenous textural patterns.In this work,an Auxiliary Classifier(AC)-Generative Adversarial Network(GAN)based Lung Cancer Classification(LCC)system is developed.The pro-posed AC-GAN-LCC system consists of three modules;preprocessing,Lungs Region Detection(LRD),and AC-GAN classification.A Wienerfilter is employed in the preprocessing module to remove the Gaussian noise.In the LRD module,only the lung regions(left and right lungs)are detected using itera-tive thresholding and morphological operations.In order to extract the lung region only,floodfilling and background subtraction.The detected lung regions are fed to the AC-GAN classifier to detect the nodules.It classifies the nodules into one of the two classes,i.e.,binary classification(such as nodules or non-nodules).The AC-GAN is the extended version of the conditional GAN that predicts the label of a given image.Three different optimization techniques,adaptive gradient optimi-zation,root mean square propagation optimization,and Adam optimization are employed for optimizing the AC-GAN architecture.The proposed AC-GAN-LCC system is evaluated on the Lung Image Database Consortium(LIDC)data-base Computed Tomography(CT)scan images.The proposed AC-GAN-LCC system classifies∼15000 CT slices(7310 non-nodules and 7685 nodules).It pro-vides an overall accuracy of 98.8%on the LIDC database using Adam optimiza-tion by a 10-fold cross-validation approach. 展开更多
关键词 Lung cancer generative adversarial network auxiliary classifier image classification system deep learning
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Cooperative Learning Makes Extensive Reading More Enjoyable
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作者 I-Chia Chou 《Sino-US English Teaching》 2012年第8期1373-1379,共7页
In the field of L2 (second language) reading, scholars generally agree that ER (extensive reading) improves L2 learners' reading speed and comprehension and enriches their L2 vocabulary (Grabe & Stoller, 1997)... In the field of L2 (second language) reading, scholars generally agree that ER (extensive reading) improves L2 learners' reading speed and comprehension and enriches their L2 vocabulary (Grabe & Stoller, 1997). This teacher-inquiry type of paper presents a practical suggestion for supplementing ER activity with the element of CL (cooperative learning). ER, theoretically speaking, focuses on the solitary task of silent reading. The CL technique used in this study was a book-talk activity. Forty-five freshmen from a course of children and young adult literatures were required to read at least 20 English books throughout a semester. CL was added to facilitate students' ER in young adult literature. After a semester, short-answer questions were asked regarding students' comments on ER as well as CL. Students overall agreed that when ER is supplemented with CL, reading in an L2 seems to be less intimidating. 展开更多
关键词 L2 (second language) reading ER (extensive reading) CL (cooperative learning)
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Cooperative Quantum Cutting of Nano-Crystalline BaF2:Tb^3+, Yb^3+ in Oxyfluoride Glass Ceramics 被引量:2
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作者 陈景鑫 叶松 +1 位作者 王玺 邱建荣 《Chinese Physics Letters》 SCIE CAS CSCD 2008年第6期2078-2080,共3页
We report on cooperative quantum cutting in Tb^3+- Yb^3+ codoped glass ceramics. Precipitation of BaF2 nanocrystals is confirmed by XRD and HRTEM analysis. Near-infrared emission due to transition of Yb^3+ ions und... We report on cooperative quantum cutting in Tb^3+- Yb^3+ codoped glass ceramics. Precipitation of BaF2 nanocrystals is confirmed by XRD and HRTEM analysis. Near-infrared emission due to transition of Yb^3+ ions under 485 nm excitation indicates cooperative energy transfer from Tb^3+ to Yb^3+. The quantum efficiency of this process reaches 145%. The realization of quantum cutting in glass ceramics may have promising applications in solar cells. 展开更多
关键词 DOWNCONVERSION SPECTROSCOPY ER3+
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锻造工艺及热处理对含Er7050铝合金组织与力学性能的影响
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作者 刘宇航 荣莉 +8 位作者 黄晖 陈炯燊 马晨曦 史晓成 魏午 文胜平 高坤元 吴晓蓝 聂祚仁 《稀有金属材料与工程》 北大核心 2026年第2期517-527,共11页
为了探究多向锻造对铝合金微观组织及力学性能的影响,以均火态含Er7050铝合金为研究对象,对该合金在400℃下进行了3种不同锻造道次的多向锻造,即三墩三拔(3U3CS)、六墩六拔(6U6CS)以及九墩九拔(9U9CS)。随后,合金经过固溶处理、水淬和T... 为了探究多向锻造对铝合金微观组织及力学性能的影响,以均火态含Er7050铝合金为研究对象,对该合金在400℃下进行了3种不同锻造道次的多向锻造,即三墩三拔(3U3CS)、六墩六拔(6U6CS)以及九墩九拔(9U9CS)。随后,合金经过固溶处理、水淬和T6时效处理。对样品进行微观结构分析和机械性能测试。通过比较3种不同锻造工艺所得样品的机械性能,发现经过九墩九拔锻造工艺处理的样品具有最佳的机械性能,这归功于该锻造工艺使其产生细小的晶粒和致密的析出强化相,该锻造工艺条件下样品的平均抗拉强度为621.4 MPa,平均屈服强度为545.4 MPa,平均伸长率为13.58%,对比其他两种锻造工艺处理的样品均有提升,这表明优化的锻造工艺显著改善了机械性能。 展开更多
关键词 含Er7050铝合金 多向锻造 显微组织演变 再结晶
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Er和Cu复合添加对A356合金组织与力学性能的影响
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作者 汤江涛 冯丽 +3 位作者 冯恩浪 姜岳峰 梁田 马颖澈 《金属热处理》 北大核心 2026年第1期12-21,共10页
通过在A356铝合金中加入0.2%、0.4%稀土元素Er及复合添加0.1%Er、1.76%Cu,研究了Er、Cu对压铸成形A356铝合金微观组织和力学性能的影响。结果表明:加入稀土元素Er后,共晶Si的形貌由长纤维状或长棒状转变为细小的纤维状或点状结构,共晶S... 通过在A356铝合金中加入0.2%、0.4%稀土元素Er及复合添加0.1%Er、1.76%Cu,研究了Er、Cu对压铸成形A356铝合金微观组织和力学性能的影响。结果表明:加入稀土元素Er后,共晶Si的形貌由长纤维状或长棒状转变为细小的纤维状或点状结构,共晶Si的共晶转变温度及α-Al的熔化温度降低。随着Er含量的增加,合金的抗拉强度由242.0 MPa小幅升高至250.0 MPa,但伸长率由7.00%降低至5.50%。在A356铝合金中复合添加0.1%Er和1.76%Cu时,合金中形成了Al_(3)Er、Al_(8)Cu_(4)Er、Al_(2)Cu等金属间化合物,合金的抗拉强度为243.0 MPa,伸长率降低为1.50%,表明Er和Cu未表现出良好的协同强韧化作用。其主要原因是快速凝固促使富Cu相以粗大块状或团簇状在枝晶间析出,导致应力集中,并在拉伸过程中于其棱角处萌生微裂纹,从而严重恶化塑性。 展开更多
关键词 压铸态 A356合金 稀土Er CU 复合协同
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内质网应激促进铁死亡加重脑缺血再灌注损伤 被引量:1
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作者 张月婷 李静林 +3 位作者 傅振燚 晏斐 高宇 刘佳鑫 《中国组织工程研究》 北大核心 2026年第11期2806-2813,共8页
背景:栓子栓塞脑动脉导致相应的脑组织缺血缺氧,在恢复血流以及再氧合时,通常会出现脑缺血再灌注损伤。然而,目前关于铁死亡与内质网应激在脑缺血再灌注损伤中相互作用的研究较为有限。目的:探讨内质网应激和铁死亡在脑缺血再灌注损伤... 背景:栓子栓塞脑动脉导致相应的脑组织缺血缺氧,在恢复血流以及再氧合时,通常会出现脑缺血再灌注损伤。然而,目前关于铁死亡与内质网应激在脑缺血再灌注损伤中相互作用的研究较为有限。目的:探讨内质网应激和铁死亡在脑缺血再灌注损伤中的作用及机制。方法:HT-22细胞系分为4组:对照组未进行造模和干预,模型组构建氧糖剥夺/再灌注模型,4-PBA组在进行氧糖剥夺/再灌注前使用1.25 mmol/L内质网应激抑制剂4-PBA处理2 h,4-PBA组+CCT组在进行氧糖剥夺/再灌注前使用1.25 mmol/L 4-PBA和5μmol/L蛋白激酶RNA样ER激酶激活剂CCT020312处理2 h。通过CCK-8实验检测细胞活力;Western blot检测铁死亡、内质网应激及蛋白激酶RNA样ER激酶/转录激活因子4信号通路相关蛋白的表达;流式细胞术检测细胞凋亡;使用试剂盒检测Fe²⁺浓度。结果与结论:与对照组相比,氧糖剥夺/再灌注处理通过诱导铁死亡、内质网应激和细胞凋亡机制显著抑制了神经细胞的增殖活性。内质网应激抑制剂4-PBA处理有效减轻了氧糖剥夺/再灌注引起的铁死亡、凋亡以及细胞活力抑制现象。此外,4-PBA还显著降低了氧糖剥夺/再灌注造模后蛋白激酶RNA样ER激酶和转录激活因子4表达水平。而PERK激活剂CCT020312则逆转了4-PBA上述作用。结果表明:内质网应激通过蛋白激酶RNA样ER激酶/转录激活因子4信号通路促进铁死亡,从而加重脑缺血再灌注损伤。 展开更多
关键词 铁死亡 内质网应激 急性缺血性脑卒中 氧糖剥夺/再灌注 细胞活力 细胞凋亡 蛋白激酶RNA样ER激酶(PERK) 转录激活因子4(ATF4)
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党参-茯苓配伍调控ERα/PI3K/Akt信号通路改善单侧颈总动脉永久结扎痴呆大鼠的认知障碍
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作者 杨佳瑶 何玉莲 +5 位作者 郭延垒 尚芳红 花雷 阳勇 张小梅 魏江平 《南方医科大学学报》 北大核心 2026年第2期247-258,共12页
目的基于UPLC-Q-TOF-MS/MS分析研究党参-茯苓配伍(CRP)治疗痴呆症的作用机制。方法采用于UPLC-Q-TOFMS/MS分析单侧颈总动脉永久结扎(UCCA)模型大鼠的CRP的入血入脑成分,并对入血和入脑成分进行网络药理学分析。CRP灌胃UCCA大鼠干预1个... 目的基于UPLC-Q-TOF-MS/MS分析研究党参-茯苓配伍(CRP)治疗痴呆症的作用机制。方法采用于UPLC-Q-TOFMS/MS分析单侧颈总动脉永久结扎(UCCA)模型大鼠的CRP的入血入脑成分,并对入血和入脑成分进行网络药理学分析。CRP灌胃UCCA大鼠干预1个月后通过Morris水迷宫评价其学习记忆能力;苏木精-伊红染色观察海马和皮质的病理形态学变化;NeuN染色分析海马和皮层神经元数量变化;采用代谢组学分析CRP治疗UCCA大鼠前后脑内代谢物变化差异;酶联免疫吸附测定(ELISA)检测脑内谷氨酸和γ-氨基丁酸(GABA)的含量;免疫组化法考察雌激素受体α(ERα)的蛋白表达;Western blotting分析p-PI3K、PI3K、p-Akt、Akt的蛋白表达。结果在UCCA大鼠的脑组织和血液中分别鉴定出125种和126种成分,其中,脑组织中发现了89种党参成分和36种茯苓成分,血液中发现了85种党参成分和41种茯苓成分。网络药理学分析表明,CRP治疗痴呆主要与调节进入脑组织的成分所影响的PI3K/Akt等信号通路有关。与假手术组比较,模型大鼠的第5天的逃避潜伏期明显延长(P<0.01),平台象限活动时间、海马和皮质的神经元明显损伤且NeuN平均光密度明显下降(P<0.05);脑内谷氨酸和GABA/谷氨酸含量明显升高(P<0.05),ERα、p-PI3K/PI3K、p-Akt/Akt蛋白表达下调(P<0.05)。与模型组比较,CRP干预大鼠的第5天的逃避潜伏期明显缩短(P<0.01),穿越平台次数、平台象限活动时间均明显增加(P<0.05),海马和皮质的神经元损伤好转且NeuN平均光密度明显升高(P<0.05);代谢组学分析表明CRP治疗作用主要富集于雌激素信号通路和GABA能突触等信号通路。CRP组大鼠脑内的谷氨酸和GABA/谷氨酸含量明显降低(P<0.05),ERα、p-PI3K/PI3K和p-Akt/Akt蛋白表达上调(P<0.05)。结论CRP能够改善UCCA痴呆大鼠的学习和记忆缺陷,这与其对脑内ERα/PI3K/Akt信号通路的调节有关。 展开更多
关键词 党参-茯苓配伍 痴呆 单侧颈总动脉永久结扎大鼠 γ-氨基丁酸 ERα/PI3K/Akt信号通路
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2.79μm侧面泵浦激光器及光纤耦合性能研究
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作者 杨航 崔建丰 +5 位作者 贾红宝 王浪 邬小娇 朱佳辉 裴文娣 李福玖 《激光与红外》 北大核心 2026年第1期18-24,共7页
实验通过设计并搭建一套LD侧面泵浦Er,Cr∶YSGG晶体的电光调Q中红外固体激光器,通过对热焦距的仿真确定500mm平-平对称腔结构。对比分析了不同泵浦脉宽下的静态、动态能量输出,实验表明在泵浦脉宽14ms下性能最佳,分别获得静态、动态能... 实验通过设计并搭建一套LD侧面泵浦Er,Cr∶YSGG晶体的电光调Q中红外固体激光器,通过对热焦距的仿真确定500mm平-平对称腔结构。对比分析了不同泵浦脉宽下的静态、动态能量输出,实验表明在泵浦脉宽14ms下性能最佳,分别获得静态、动态能量输出12835mJ和1551mJ、动静比为3126、电-光转换效率079。此外,实验通过耦合空芯光纤与光子晶体光纤进行传能测试,结果表明空芯光纤与光子晶体光纤传输效率分别为50和70,并进行有限元仿真分析,其中光子晶体光纤在279μm波段的损耗和色散分别为001224dB/m和-230 ps/(nm·km)。 展开更多
关键词 Er Cr∶YSGG激光器 LD侧面泵浦 光纤耦合 Ag/AgI空芯光纤 光子晶体光纤
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基于孪生网络的抗乳腺癌药物活性筛选研究
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作者 李杨飞 汪秋蒙 代华蓉 《现代信息科技》 2026年第4期138-145,152,共9页
乳腺癌是女性最常见的恶性肿瘤之一,亟须精准高效的候选药物筛选方法。文中提出一种基于孪生网络的三层筛选框架:首先通过K-means聚类与互信息分析筛选关键分子描述符,缓解高维冗余问题;其次采用双分支多层感知机分别预测IC50_nM与pIC50... 乳腺癌是女性最常见的恶性肿瘤之一,亟须精准高效的候选药物筛选方法。文中提出一种基于孪生网络的三层筛选框架:首先通过K-means聚类与互信息分析筛选关键分子描述符,缓解高维冗余问题;其次采用双分支多层感知机分别预测IC50_nM与pIC50,并利用孪生网络增强小样本ADMET数据,提升分类性能;最后结合遗传算法与决策树规则实现多目标优化。实验结果显示,模型在活性预测中误差降低15.2%,ADMET分类精度提升至87.5%,成功筛选出632种兼具活性与成药性的潜在候选分子,为抗乳腺癌药物早期研发提供了有力的计算支撑。 展开更多
关键词 乳腺癌 雌激素受体α(ERα) 孪生网络 生物活性预测 ADMET性质优化 候选药物筛选
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煤矿用纤维增强复合材料隔爆外壳的安全性研究
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作者 刘隽宁 刘得英 +3 位作者 赵军 任飞 辛丽娜 柴妤卓 《矿业研究与开发》 北大核心 2026年第1期255-263,共9页
为满足煤矿井下设备轻量化与防爆安全需求,采用玻璃纤维/环氧树脂复合材料(GF/ER)制备出一种容积为19.5 L的I类非金属轻型隔爆外壳,并通过材料性能测试、有限元仿真及多项防爆安全试验分析GF/ER型隔爆外壳的综合性能。结果表明:GF/ER型... 为满足煤矿井下设备轻量化与防爆安全需求,采用玻璃纤维/环氧树脂复合材料(GF/ER)制备出一种容积为19.5 L的I类非金属轻型隔爆外壳,并通过材料性能测试、有限元仿真及多项防爆安全试验分析GF/ER型隔爆外壳的综合性能。结果表明:GF/ER型隔爆外壳满足煤矿井下设备对高力学强度、高阻燃性(V-0级)和抗静电性的要求;GF/ER型隔爆外壳的拉伸性能、弯曲性能及冲击强度变化率均小于10%,表明其具有优异的耐久性和环境适应性;在参考压力测试中,GF/ER型隔爆外壳的最大爆炸压力达0.496 MPa,极限承压能力为3.1 MPa,远超标准要求的1.5 MPa;在工作载荷下,GF/ER型隔爆外壳隔爆面间隙变形小于0.15 mm,结构稳定可靠;与同等尺寸金属隔爆箱相比,GF/ER型隔爆外壳实现了超过50%的减重效果,显著降低井下作业负担,提升了移动设备续航能力。研究成果为矿用装备轻量化提供了可行的技术路径和理论依据。 展开更多
关键词 纤维增强复合材料 GF/ER型隔爆外壳 物理化学特性 防爆安全 有限元分析
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治乳腺癌前,一定要做这项检查
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作者 谢晓 《健康养生》 2026年第3期73-73,共1页
对女人而言,雌激素很重要,但它却也是乳腺癌的推手。甲乳疾病专家王深明教授提醒:“发现乳腺癌后,一定要检测癌细胞是否表达雌激素受体(ER)。”化疗、放疗之外,还可尝试这个“很多病人在乳腺癌手术、化疗后,使用内分泌治疗,有效提高了... 对女人而言,雌激素很重要,但它却也是乳腺癌的推手。甲乳疾病专家王深明教授提醒:“发现乳腺癌后,一定要检测癌细胞是否表达雌激素受体(ER)。”化疗、放疗之外,还可尝试这个“很多病人在乳腺癌手术、化疗后,使用内分泌治疗,有效提高了生存期限。”对内分泌治疗,王深明教授建议乳腺癌患者都应该了解。 展开更多
关键词 ER检测 内分泌治疗 雌激素 乳腺癌
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Endoplasmic reticulum:Regulator of structural potentiation of dendritic spines
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作者 Philip J.Dittmer Mark L.Dell’Acqua 《Neural Regeneration Research》 2026年第3期1114-1115,共2页
Since the first electron micrograph of“lace-like structures”over 75 years ago,the endoplasmic reticulum(ER)is now viewed as a highly dynamic,constantly remodeling,continuous network of tubules and cisternae that pla... Since the first electron micrograph of“lace-like structures”over 75 years ago,the endoplasmic reticulum(ER)is now viewed as a highly dynamic,constantly remodeling,continuous network of tubules and cisternae that plays an important role in a broad range of cellular activities from calcium regulation to protein synthesis and trafficking.In neurons,the ER extends from the soma through the axon to presynaptic terminals,and throughout the dendritic arbor into as many as half of all postsynaptic dendritic spines at any given time(Falahati et al.,2022). 展开更多
关键词 calcium regulation endoplasmic reticulum er dendritic arbor TRAFFICKING tubules cisternae dendritic spines protein synthesis endoplasmic reticulum
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Chitinase boosts endoplasmic reticulum stress and triggers apoptosis and autophagy in a hepatocellular carcinoma rat model
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作者 Asmaa I.Nabeel Fatma S.M.Moawed Enas M.Moustafa 《Asian Pacific Journal of Tropical Biomedicine》 2026年第3期129-138,共10页
Objective:To assess the antitumor activity of the novel chitinase produced by fermented,isolated Trichoderma viride in a hepatocellular carcinoma(HCC)male rat model.Methods:Diethyl-nitrosamine induction combined with ... Objective:To assess the antitumor activity of the novel chitinase produced by fermented,isolated Trichoderma viride in a hepatocellular carcinoma(HCC)male rat model.Methods:Diethyl-nitrosamine induction combined with ionizing radiation exposure was used to establish the HCC rat model.All rats were divided into 4 groups:the control group,the chitinase group,the HCC group,and the HCC+chitinase group.The antiproliferative effect of chitinase was evaluated in human HCC cells.The effect of chitinase in vivo on oxidative stress,endoplasmic reticulum stress chaperones,autophagy markers,PI3K/AKT/mTOR,AMPK pathway expression,and apoptotic indicators was determined and confirmed by histological examination.Results:Chitinase significantly inhibited the viabilities of HepG2 cells.Moreover,in the Wistar male rat model of HCC,chitinase decreased ATP levels,modulated endoplasmic reticulum stress,mediated autophagy factors,and promoted apoptosis.Conclusions:Chitinase might play a role in the apoptosis as well as autophagy pathways and may act as a potential tumor suppressor. 展开更多
关键词 Trichoderma viride CHITINASE Hepatocellular carcinoma ER stress APOPTOSIS AUTOPHAGY PI3K/AKT/MTOR AMPK
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基于多尺度检测卷积的光学遥感图像目标检测方法研究
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作者 郭欣怡 吕晨阳 印通 《机电信息》 2026年第5期42-45,50,共5页
光学遥感图像目标检测是遥感领域的关键技术之一。遥感图像具有目标尺度变化剧烈的特点,对图像目标检测准确率影响较大,常见的基于无锚框的目标检测方法在自然图像检测领域具有优势,但对光学遥感图像进行检测时效果不理想。因此,设计一... 光学遥感图像目标检测是遥感领域的关键技术之一。遥感图像具有目标尺度变化剧烈的特点,对图像目标检测准确率影响较大,常见的基于无锚框的目标检测方法在自然图像检测领域具有优势,但对光学遥感图像进行检测时效果不理想。因此,设计一个多尺度检测卷积结构(Multi-scale Detection Convolution Structure,MDCS),在没有先验信息的情况下,自适应拟合具有不规则纵横比的多尺度目标边界框,加强神经网络对多尺度目标的响应。基于CenterNet无锚框检测方法,引入多尺度检测卷积结构提出了一个遥感图像多尺度检测网络(Multi-scale Detection Convolutional Network,MDCNet)。基于MDCNet网络模型在DOTA光学遥感数据集上进行遥感图像目标检测实验,实现了67.3%的遥感图像目标检测准确率,验证了MDCNet网络对于多尺度目标检测性能提升的有效性。 展开更多
关键词 图像目标检测 光学遥感图像 Cent er Net 卷积神经网络
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Salvia miltiorrhiza extract improves menopausal symptoms in naturally aged mice
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作者 Jeong Eun Kwon Yeong-Geun Lee +4 位作者 Hyukjin Kwon Jihyeong Park Gavin Kim Young-Mi Cho Se Chan Kang 《Asian Pacific Journal of Tropical Biomedicine》 2026年第3期119-128,I0001-I0003,共13页
Objective:To investigate the efficacy and underlying mechanisms of standardized Salvia miltiorrhiza extract(SMEX)in alleviating menopausal symptoms using MCF-7 cells and an ovary-intact menopause mouse model resulting... Objective:To investigate the efficacy and underlying mechanisms of standardized Salvia miltiorrhiza extract(SMEX)in alleviating menopausal symptoms using MCF-7 cells and an ovary-intact menopause mouse model resulting from hypothalamic-pituitary-ovarian axis aging.Methods:Estrogen receptor(ER)-related molecular responses were first assessed in MCF-7 cells treated with SMEX.In vivo efficacy was then evaluated in 52-week-old female mice orally administered SMEX(50 or 100 mg/kg/day)or 17β-estradiol(E2)for 12 weeks.ER expression and downstream AKT/ERK signaling pathways in uterine tissues were determined.In addition,histological analysis of reproductive organs,assessment of serum lipid and hormone levels,neurotransmitter measurements,and behavioral tests were performed.Results:SMEX upregulated ERαand ERβexpression and suppressed pS2 mRNA in MCF-7 cells,indicating selective ER modulation.In SMEX-treated mice,uterine ER expression and activation of the AKT and ERK pathways were significantly increased,leading to partial restoration of epithelial thickness and stratification in the oviduct and vagina.SMEX also significantly reduced serum low-density lipoprotein cholesterol levels and reversed menopausal alterations in the follicle-stimulating hormone/luteinizing hormone ratio.Additionally,it elevated serotonin and norepinephrine levels in the pituitary,thereby alleviating depression-like behavior.Conclusions:SMEX modulates ER signaling and improves neurohormonal balance,effectively alleviating menopausal symptoms in both in vitro and in vivo models.This highlights its potential as a safe,natural alternative to hormone replacement therapy and as a promising functional ingredient in therapeutic natural products. 展开更多
关键词 Salvia miltiorrhiza extract Selective ER modulation Ovary-intact menopause model
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Er:YAG激光在糖尿病肾病并发牙周炎中的应用及对牙周状态、肾功能、龈沟液炎症因子的影响
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作者 么远 曹佳佳 +4 位作者 殷悦 赵志宇 毕磊 卢娜 张春光 《检验医学与临床》 2026年第1期101-105,111,共6页
目的探讨Er:YAG激光在糖尿病肾病并发牙周炎中的应用及对牙周状态、肾功能、龈沟液炎症因子的影响。方法选取2021年4月至2024年11月该院收治的124例糖尿病肾病并发牙周炎患者作为研究对象,按照治疗方法将所有患者分为基础组和激光组,每... 目的探讨Er:YAG激光在糖尿病肾病并发牙周炎中的应用及对牙周状态、肾功能、龈沟液炎症因子的影响。方法选取2021年4月至2024年11月该院收治的124例糖尿病肾病并发牙周炎患者作为研究对象,按照治疗方法将所有患者分为基础组和激光组,每组62例。基础组给予牙周基础治疗,激光组在基础组治疗的基础上给予Er:YAG激光治疗。比较基础组和激光组患者的临床疗效、牙周状态相关指标[探诊深度(PD)、改良龈沟出血指数(mSBI)、牙齿松动度(TM)、临床附着丧失(CAL)]、肾功能和血糖指标[尿素氮(BUN)、血肌酐(SCr)、糖化血红蛋白(HbA1c)]、龈沟液炎症因子[肿瘤坏死因子(TNF)-α、基质金属蛋白酶(MMP)-8、细胞间黏附分子(ICAM)-1]。结果激光组治疗总有效率高于基础组,差异有统计学意义(P<0.05)。基础组和激光组治疗后PD、mSBI、TM、CAL均小于治疗前,SCr、BUN、HbA1c、TNF-α、MMP-8、ICAM-1水平均低于治疗前,且激光组治疗后PD、mSBI、TM、CAL均小于基础组,TNF-α、MMP-8、ICAM-1水平均低于基础组,差异均有统计学意义(P<0.05)。结论Er:YAG激光联合牙周基础治疗糖尿病肾病并发牙周炎有助于改善牙龈症状,降低炎症反应,促进患者康复。 展开更多
关键词 Er:YAG激光治疗 牙周基础治疗 糖尿病肾病 牙周炎 炎症反应
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Nd:YAG激光和Er:YAG激光治疗2型糖尿病患者种植体周围炎的短期效果评价
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作者 孙斌 王苹 《上海口腔医学》 2026年第1期54-59,共6页
目的:评价Nd:YAG激光和Er:YAG激光治疗2型糖尿病患者种植体周围炎的短期效果。方法:选择2021年2月—2024年2月收治的2型糖尿病种植体周围炎患者97例,采用随机数字表法分为A组(48例,Nd:YAG激光)和B组(49例,Er:YAG激光)。对比两组患者治... 目的:评价Nd:YAG激光和Er:YAG激光治疗2型糖尿病患者种植体周围炎的短期效果。方法:选择2021年2月—2024年2月收治的2型糖尿病种植体周围炎患者97例,采用随机数字表法分为A组(48例,Nd:YAG激光)和B组(49例,Er:YAG激光)。对比两组患者治疗前后的牙周指标、炎性因子水平、骨吸收程度、龈沟液细菌含量、血糖水平、生活质量评分及疗效。结果:治疗后,两组龈沟出血指数(sulcus bleeding index,SBI)、菌斑指数(plaque index,PLI)和牙周探诊深度(probing depth,PD)显著降低,且A组SBI、PLI和PD均显著低于B组(P<0.05)。治疗后,两组近、远中边缘骨吸收显著降低,且A组显著低于B组(P<0.05)。两组炎性因子水平治疗后显著降低,A组白细胞介素6(IL-6)、肿瘤坏死因子α(tumor necrosis factorα,TNF-α)和基质金属蛋白酶8(matrix metalloproteinase-8,MMP-8)水平均显著低于B组(P<0.05)。两组龈沟液细菌含量治疗后显著降低,且A组显著低于B组(P<0.05)。治疗前、后两组患者血糖水平相比无显著差异(P>0.05)。治疗后,两组生活质量评分显著升高,A组躯体功能、心理功能及总分均显著高于B组(P<0.05)。两组治疗总有效率相比,无显著差异(P>0.05)。结论:Nd:YAG激光治疗2型糖尿病患者种植体周围炎能有效改善牙周情况,减少骨吸收,降低炎性因子水平及龈沟液细菌含量,提高生活质量。 展开更多
关键词 ND:YAG激光 ER:YAG激光 2型糖尿病 种植体周围炎 牙周指标
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