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IRS辅助MU-MISO系统中基于深度残差学习的信道估计
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作者 陈发堂 朱鹏云 +1 位作者 杨涛 孙宸 《电讯技术》 北大核心 2024年第7期1079-1087,共9页
针对智能反射表面辅助多用户通信系统中传统信道估计方法性能下降的问题,将信道估计问题转化为信道去噪问题,利用深度残差学习方法学习残差噪声,从含噪导频信号中恢复信道系数。同时为提升信道估计精度,设计信道估计网络进一步提升去噪... 针对智能反射表面辅助多用户通信系统中传统信道估计方法性能下降的问题,将信道估计问题转化为信道去噪问题,利用深度残差学习方法学习残差噪声,从含噪导频信号中恢复信道系数。同时为提升信道估计精度,设计信道估计网络进一步提升去噪性能。网络主体包含两个模块:拼接信息保留模块将每一层卷积输出相融合,防止信道特征丢失,有效提取信道噪声的主体特征;扩张卷积稀疏模块通过扩大感受野范围获得信道的重要结构和细节特征,恢复信道噪声的边缘细节特征。仿真结果表明,归一化均方误差约等于0.45时,所提方法在不明显增加复杂度情况下,相比于线性最小均方误差算法获得3.7 dB的信噪比增益,更为接近最小均方误差信道估计器的性能,表现出了更好的性能和可用性。 展开更多
关键词 mu-MISO系统 智能反射面 信道估计 深度残差学习 扩张卷积
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针对MUS求解问题的加强剪枝策略
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作者 蒋璐宇 欧阳丹彤 +1 位作者 董博文 张立明 《软件学报》 EI CSCD 北大核心 2024年第4期1964-1979,共16页
极小不可满足子集(minimal unsatisfiable subsets,MUS)的求解是布尔可满足性问题中的一个重要子问题.对于一个给定的不可满足问题,其MUS的求解能够反映出问题中导致其不可满足的关键原因.然而,MUS的求解是一项极其耗时的任务,不同的剪... 极小不可满足子集(minimal unsatisfiable subsets,MUS)的求解是布尔可满足性问题中的一个重要子问题.对于一个给定的不可满足问题,其MUS的求解能够反映出问题中导致其不可满足的关键原因.然而,MUS的求解是一项极其耗时的任务,不同的剪枝过程将直接影响到搜索空间的大小、算法的迭代次数,从而影响算法的求解效率.提出一种针对MUS求解的加强剪枝策略ABC(accelerating by critical MSS),依据MSS、MCS、MUS这3者之间的对偶性和碰集关系特点,提出cMSS和subMUS概念,并总结出4条性质,即每个MUS必是subMUS的超集,进而在避免对MCS的碰集进行求解的情况下有效利用MUS和MCS互为碰集的特征,有效避免求解碰集时的时间开销.当subMUS不可满足时,则subMUS是唯一的MUS,算法将提前结束执行;当subMUS可满足时,则剪枝掉此节点,进而有效避免对求解空间中的冗余空间进行搜索.同时,通过理论证明ABC策略的有效性,并将其应用于目前最高效的单一化模型算法MARCO和双模型算法MARCO-MAM,在标准测试用例下的实验结果表明,该策略可以有效地对搜索空间进行进一步剪枝,从而提高MUS的枚举效率. 展开更多
关键词 极小不可满足子集 极大可满足子集 muS枚举 幂集探索 不可行分析
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β-catenin accumulation in nuclei of hepatocellular carcinoma cells up-regulates glutathione-s-transferase M3 mRNA 被引量:1
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作者 Yu-Sang Li Min Liu +1 位作者 Yoshihiro Nakata He-Bin Tang 《World Journal of Gastroenterology》 SCIE CAS CSCD 2011年第13期1772-1778,共7页
AIM: To identify the differentially over-expressed genes associated with β-catenin accumulation in nuclei of hepatocellular carcinoma (HCC) cells. METHODS: Differentially expressed genes were identified in radiation-... AIM: To identify the differentially over-expressed genes associated with β-catenin accumulation in nuclei of hepatocellular carcinoma (HCC) cells. METHODS: Differentially expressed genes were identified in radiation-induced B6C3 F1 mouse HCC cells by mRNA differential display, Northern blot and RT-PCR, respectively. Total glutathione-s-transferase (GST) activity was measured by GST activity assay and β-catenin localization was detected with immunostaining in radiation-induced mouse HCC cells and in HepG2 cell lines.RESULTS: Two up-regulated genes, glutamine synthetase and glutathione-s-transferase M3 (GSTM3), were identified in radiation-induced mouse HCC cells. Influence of β-catenin accumulation in nuclei of HCC cells on upregulation of GSTM3 mRNA was investigated. The nearby upstream domain of GSTM3 contained the β-catenin/TcfLef consensus binding site sequences [5'-(A/T)(A/T) CAAAG-3'], and the total GST activity ratio was considerably higher in B6C3F1 mouse HCC cells with β-catenin accumulation in nuclei of HCC cells than in those without β-catenin accumulation (0.353 ± 0.117vs 0.071 ± 0.064, P < 0.001). The TWS119 (a distinct GSK-3β inhibitor)-induced total GST activity was significantly higher in HepG2 cells with β-catenin accumulation than in those without β-catenin accumulation in nuclei of HCC cells. Additionally, the GSTM3 mRNA level was significantly higher at 24 h than at 12 h in TWS119-treated HepG2 cells. CONCLUSION: β-catenin accumulation increases GST activity in nuclei of HCC cells, and GSTM3 may be a novel target gene of the β-catenin/Tcf-Lef complex. 展开更多
关键词 β-catenin accumulation Differential display analysis glutathione-s-transferase M3 Hepatocellular carcinoma RADIATION
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大规模离散MU-MIMO:低复杂度、信息理论最优检测与多用户编码
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作者 陈学辉 池育浩 刘雷 《中兴通讯技术》 北大核心 2024年第1期46-54,共9页
研究了一种实际的大规模离散多用户多输入多输出(MU-MIMO)系统,涵盖了大规模天线与用户、实用的信道编译码、任意输入分布、仅接收机已知信道状态信息、一般右酉不变信道矩阵、模数转化器等实际通信约束。针对理想和低分辨率模数转换器... 研究了一种实际的大规模离散多用户多输入多输出(MU-MIMO)系统,涵盖了大规模天线与用户、实用的信道编译码、任意输入分布、仅接收机已知信道状态信息、一般右酉不变信道矩阵、模数转化器等实际通信约束。针对理想和低分辨率模数转换器下的大规模离散MU-MIMO系统,分别提出了低复杂度、信息理论最优接收机和多用户码设计准则,并给出实际多用户低密度奇偶校验码(LDPC)设计。数值实验证实所设计的多用户LDPC比现有的单用户LDPC获得了2~5dB性能增益,同时还解决在信道恶劣和低分辨率模数转换器下单用户码无法准确恢复信息的难题,揭示了现有贝叶斯最优接收机与单用户码直接结合不再是最优方案。 展开更多
关键词 大规模离散mu-MIMO 低复杂度 信息理论最优 迭代接收机 多用户码
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Immunoprophylactic potential of filarial glutathione-s-transferase in lymphatic filariaisis
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作者 Madhusmita Bal Mandal N +2 位作者 Achary KG Das MK Kar SK 《Asian Pacific Journal of Tropical Medicine》 SCIE CAS 2011年第3期185-191,共7页
Objective:To elucidates the immunoprophylactic potential of glutathion-s-transferase(GST) from cattle filarial parasite Setaria digitata(S.digitata) against lymphatic filariasis.Methods: GST was purified through affin... Objective:To elucidates the immunoprophylactic potential of glutathion-s-transferase(GST) from cattle filarial parasite Setaria digitata(S.digitata) against lymphatic filariasis.Methods: GST was purified through affinity chromatography(SdGST) and chacterized by SDS-PAGE and Nano-LC MS/MS analysis.Antibody isotypes to SdGST were measured by ELISA.Antibody dependant cellular cytotoxicity(ADCC) was performed in vitro using sera from immunized animals and immune individuals.T-cell proliferation and cytokine response to SdGST in different groups of filariasis were measured.Immunoprophylactic potential of SdGST was evaluate in animal model.Results:SdGST exhibited 30-fold enhancement of enzyme activity over crude parasitic extract.It was found to be 26 kDa by SDS-PAGE.Nano LC-MS/MS analysis followed by blast search showed 100%homology with Dirqfilaria immitis(D.immitis) and only 43%with Homo sapiens(H.sapiens).Immunoblotting analysis showed putatively immune individuals carry significant level of antibodies to SdGST as compared with microfilaraemics.Immunized sera and sera endemic normal could neutralize the enzymatic activity of SdGST and inducing in vitro cytotoxicity of microfilariae.Peripheral blood mononuclear cells(PBMC) from endemic normals upon stimulation with SdGST showed a mixed type of Th1/Th2 response.SdGST immunization clear microfilariae from circulation in S.digitata implanted mastomys.Conclusions:The heterologous GST could be potentially developed as a vaccine candidate against lymphatic filarial parasite. 展开更多
关键词 glutathione-s-transferase SETARIA digitata LYMPHATIC FILARIASIS
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Vertical distribution characteristics of soil saturated hydraulic conductivity under different land use patterns in the Mu Us sandy land
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作者 LIU Xingting QIAO Jiangbo +4 位作者 YANG Tao MA Yali TIAN Hanyang HAN Xiaoyang ZHU Yuanjun 《地球环境学报》 CSCD 2024年第4期665-674,共10页
Background,aim,and scope Soil saturated hydraulic conductivity(K_(s))is a key parameter in the hydrological cycle of soil;however,we have very limited understanding of K_(s)characteristics and the factors that inf lue... Background,aim,and scope Soil saturated hydraulic conductivity(K_(s))is a key parameter in the hydrological cycle of soil;however,we have very limited understanding of K_(s)characteristics and the factors that inf luence this key parameter in the Mu Us sandy land(MUSL).Quantifying the impact of changes in land use in the Mu Us sandy land on K_(s)will provide a key foundation for understanding the regional water cycle,but will also provide a scientific basis for the governance of the MUSL.Materials and methods In this study,we determined K_(s)and the basic physical and chemical properties of soil(i.e.,organic matter,bulk density,and soil particle composition)within the first 100 cm layer of four different land use patterns(farmland,tree,shrub,and grassland)in the MUSL.The vertical variation of K_(s)and the factors that influence this key parameter were analyzed and a transfer function for estimating K_(s)was established based on a multiple stepwise regression model.Results The K_(s)of farmland,tree,and shrub increased gradually with soil depth while that of grassland remained unchanged.The K_(s)of the four patterns of land use were moderately variable;mean K_(s)values were ranked as follows:grassland(1.38 mm·min^(-1))<tree(1.76 mm·min^(-1))<farmland(1.82 mm·min^(-1))<shrub(3.30 mm·min^(-1)).The correlation between K_(s)and organic matter,bulk density,and soil particle composition,varied across different land use patterns.A multiple stepwise regression model showed that silt,coarse sand,bulk density,and organic matter,were key predictive factors for the K_(s)of farmland,tree,shrub,and grassland,in the MUSL.Discussion The vertical distribution trend for K_(s)in farmland is known to be predominantly influenced by cultivation,fertilization,and other factors.The general aim is to improve the water-holding capacity of shallow soil on farmland(0-30 cm in depth)to conserve water and nutrients;research has shown that the K_(s)of farmland increases with soil depth.The root growth of tree and shrub in sandy land exerts mechanical force on the soil due to biophysical processes involving rhizospheres,thus leading to a significant change in K_(s).We found that shallow high-density fine roots increased the volume of soil pores and eliminated large pores,thus resulting in a reduction in shallow K_(s).Therefore,the K_(s)of tree and shrub increased with soil depth.Analysis also showed that the K_(s)of grassland did not change significantly and exhibited the lowest mean value when compared to other land use patterns.This finding was predominantly due to the shallow root system of grasslands and because this land use pattern is not subject to human activities such as cultivation and fertilization;consequently,there was no significant change in K_(s)with depth;grassland also had the lowest mean K_(s).We also established a transfer function for K_(s)for different land use patterns in the MUSL.However,the predictive factors for K_(s)in different land use patterns are known to be affected by soil cultivation methods,vegetation restoration modes,the distribution of soil moisture,and other factors,thus resulting in key differences.Therefore,when using the transfer function to predict K_(s)in other areas,it will be necessary to perform parameter calibration and further verification.Conclusions In the MUSL,the K_(s)of farmland,tree,and shrub gradually increased with soil depth;however,the K_(s)of grassland showed no significant variation in terms of vertical distribution.The mean K_(s)values of different land use patterns were ranked as follows:shrub>farmland>tree>grassland;all land use patterns showed moderate levels of variability.The K_(s)for different land use patterns exhibited differing degrees of correlation with soil physical and chemical properties;of these,clay,silt,sand,bulk density,and organic matter,were identified as important variables for predicting K_(s)in farmland,tree,shrub,and grassland,respectively.Recommendations and perspectives In this study,we used a stepwise multiple regression model to establish a transfer function prediction model for K_(s)for different land use patterns;this model possessed high estimation accuracy.The ability to predict K_(s)in the MUSL is very important in terms of the conservation of water and nutrients. 展开更多
关键词 mu Us sandy land saturated hydraulic conductivity vertical distribution transfer function
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Ecological effect of the plantation of Sabina vulgaris in the Mu Us Sandy Land,China
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作者 NAN Weige DONG Zhibao +2 位作者 ZHOU Zhengchao LI Qiang CHEN Guoxiang 《Journal of Arid Land》 SCIE CSCD 2024年第1期14-28,共15页
Vegetation restoration through artificial plantation is an effective method to combat desertification,especially in arid and semi-arid areas.This study aimed to explore the ecological effect of the plantation of Sabin... Vegetation restoration through artificial plantation is an effective method to combat desertification,especially in arid and semi-arid areas.This study aimed to explore the ecological effect of the plantation of Sabina vulgaris on soil physical and chemical properties on the southeastern fringe of the Mu Us Sandy Land,China.We collected soil samples from five depth layers(0-20,20-40,40-60,60-80,and 80-100 cm)in the S.vulgaris plantation plots across four plantation ages(4,7,10,and 16 years)in November 2019,and assessed soil physical(soil bulk density,soil porosity,and soil particle size)and chemical(soil organic carbon(SOC),total nitrogen(TN),available nitrogen(AN),available phosphorus(AP),available potassium(AK),cation-exchange capacity(CEC),salinity,p H,and C/N ratio)properties.The results indicated that the soil predominantly consisted of sand particles(94.27%-99.67%),with the remainder being silt and clay.As plantation age increased,silt and very fine sand contents progressively rose.After 16 years of planting,there was a marked reduction in the mean soil particle size.The initial soil fertility was low and declined from 4 to 10 years of planting before witnessing an improvement.Significant positive correlations were observed for the clay,silt,and very fine sand(mean diameter of 0.000-0.100 mm)with SOC,AK,and p H.In contrast,fine sand and medium sand(mean diameter of 0.100-0.500 mm)showed significant negative correlations with these indicators.Our findings ascertain that the plantation of S.vulgaris requires 10 years to effectively act as a windbreak and contribute to sand fixation,and needs 16 years to improve soil physical and chemical properties.Importantly,these improvements were found to be highly beneficial for vegetation restoration in arid and semi-arid areas.This research can offer valuable insights for the protection and restoration of the vegetation ecosystem in the sandy lands in China. 展开更多
关键词 Sabina vulgaris plantation age soil physical and chemical properties soil particle size soil fertility vegetation restoration mu Us Sandy Land
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糖尿病小鼠肾小管上皮细胞HNF4A和MUCDHL下调促进肾纤维化
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作者 贾静 梁露群 +10 位作者 谭万林 许晓晓 阮媛媛 李霜 陈荣誉 余雄 王方芳 陈钰婷 彭玉琳 郭兵 王圆圆 《中国病理生理杂志》 CAS CSCD 北大核心 2024年第6期1085-1096,共12页
目的:探索肝细胞核因子4α(HNF4A)和μ-原钙黏蛋白(MUCDHL)在糖尿病小鼠肾脏中的作用和联系。方法:(1)选取12周龄的db/m小鼠和db/db小鼠各6只,正常饮食喂养至16周,Western blot检测肾组织纤维连接蛋白(FN)、Ⅲ型胶原(Col-Ⅲ)、上皮钙黏... 目的:探索肝细胞核因子4α(HNF4A)和μ-原钙黏蛋白(MUCDHL)在糖尿病小鼠肾脏中的作用和联系。方法:(1)选取12周龄的db/m小鼠和db/db小鼠各6只,正常饮食喂养至16周,Western blot检测肾组织纤维连接蛋白(FN)、Ⅲ型胶原(Col-Ⅲ)、上皮钙黏素(E-cadherin)、α-平滑肌肌动蛋白(α-SMA)、HNF4A、Snail和MUCDHL的蛋白水平,免疫组织化学染色观察FN、HNF4A和MUCDHL蛋白的表达及分布情况。(2)体外培养小鼠肾小管上皮细胞(mRTEC),分为正常糖(NG)组、高糖(HG)组、过表达对照组(NG+vector组和HG+vector组)、过表达组(NG+OE-MUCDHL组、HG+OE-MUCDHL组、NG+OE-HNF4A组和HG+OE-HNF4A组)、敲减对照组(NG+control组和HG+control组)和敲减组(NG+si-MUCDHL组、HG+si-MUCDHL组、NG+si-HNF4A组和HG+si-HNF4A组),Western blot检测相关指标的蛋白水平。结果:(1)与db/m组相比,db/db组体重、血糖和尿白蛋白/肌酐比值均显著升高(P<0.05),提示db/db小鼠有明显肾损伤;与db/m组相比,db/db组FN、Col-Ⅲ、α-SMA和Snail蛋白表达升高,E-cadherin、HNF4A和MUCDHL蛋白表达降低(P<0.05);MUCDHL主要表达在肾小管上皮细胞顶端膜,FN主要表达在肾小管间质,HNF4A主要表达在肾小管细胞浆和细胞核。(2)与NG组相比,HG组FN、Col-Ⅲ、α-SMA和Snail蛋白表达升高,E-cadherin、HNF4A和MUCDHL蛋白表达降低(P<0.05);过表达MUCDHL后FN、Col-Ⅲ、α-SMA和Snail蛋白表达降低,E-cadherin和MUCDHL蛋白表达升高(P<0.05),HNF4A表达不变;敲减MUCDHL后相关指标表达与上述效应相反(P<0.05),HNF4A表达不变;过表达HNF4A可使MUCDHL表达增加,其余指标的表达变化与过表达MUCDHL一致;敲减HNF4A表达可使上述效应反转(P<0.05);MUCDHL可能是HNF4A的下游靶基因。结论:HNF4A和MUCDHL在糖尿病小鼠肾小管中表达降低。HNF4A可能通过上调MUCDHL的表达延缓糖尿病肾病肾纤维化进程。 展开更多
关键词 糖尿病肾病 纤维化 μ-原钙黏蛋白 肝细胞核因子4Α
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移动的“地界”(mu ddix):小凉山彝族家支的分化与整合
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作者 杨铭君 李建明 《原生态民族文化学刊》 北大核心 2024年第4期141-152,156,共13页
家支制度被认为是凉山彝族社会政治制度的重要组成部分,它向内凝聚了血缘共同体的团结,向外抵御了共同体潜在的风险。因此,一般认为家支仅仅是以血缘世系为纽带进行整合的。通过对近代以来云南小凉山的考察发现,在有“等级团结”关系的... 家支制度被认为是凉山彝族社会政治制度的重要组成部分,它向内凝聚了血缘共同体的团结,向外抵御了共同体潜在的风险。因此,一般认为家支仅仅是以血缘世系为纽带进行整合的。通过对近代以来云南小凉山的考察发现,在有“等级团结”关系的彝族社会中,家支具有延展性,它既指一个具有血缘世系纽带的群体,也指具有等级涵盖关系的家支联合体。在本土概念中将其归纳为“地界”(mu ddix)。“地界”是指在小凉山彝族社会内部以诺伙家支为名号,诺伙、曲诺、阿加和呷西这三层身份关系为基础,以家支地界利益为最高原则来组成和维系共同体运转的法权机制,以此来讨论小凉山彝族社会中的家支构成关系、运转逻辑与分化原则。只有理解了“地界”中家支分化与整合的关系才能真正厘清小凉山彝族社会运行的基本逻辑。 展开更多
关键词 地界 家支 小凉山 彝族 社会整合
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Simultaneous Waveform Inverse Modelling for Litho-Fluid Prediction in an Old Marginal, “Agbbo”Field, Onshore Niger Delta, Nigeria
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作者 Charles Chibueze Ugbor Peter Ogobi Odong Chukwuemeka Austine Okonkwo 《Journal of Geoscience and Environment Protection》 2024年第5期40-59,共20页
Simultaneous waveform inversion was used to predict lithofacies and fluid type across the field. Very often, characterizing reservoirs in terms of lithology and fluid type using conventional methods is replete with un... Simultaneous waveform inversion was used to predict lithofacies and fluid type across the field. Very often, characterizing reservoirs in terms of lithology and fluid type using conventional methods is replete with uncertainties, especially in marginal fields. An approach is employed in this study that integrated rock physics and waveform inverse modelling for lithology and fluid-type characterization to appropriately identify potential hydrocarbon saturated zones and their corresponding lithology. Seismic and well-log data were analyzed using Hampson Russel software. The method adopted includes lithofacies and fluid content analysis using rock physics parameters and seismic simultaneous inverse modelling. Rock physics analysis identified 2 broad reservoirs namely: HDZ1 and HDZ2 reservoirs. Results from the inverse modelling showed that low values of acoustic impedance from 19,743 to 20,487 (ft/s)(g/cc) reflect hydrocarbon-bearing reservoirs while medium to high values shows brine and shale respectively, with brine zone ranging from 20,487 to 22,531 (ft/s)(g/cc) and shale above 22,531 (ft/s)(g/cc). Two lithofacies were identified from inversion analysis of Vp/Vs and Mu-Rho, namely: sand and shale with VpVs 1.95 values respectively. Mu-Rho > 12.29 (GPa)(g/cc) and <12.29 (GPa) (g/cc) represent sand and shale respectively. From 3D volume, it was observed that a high accumulation of hydrocarbon was observed to be saturated at the north to the eastern part of the field forming a meandering channel. Sands were mainly distributed around the northeastern to the southwestern part of the field, that tends to be away from Well 029. This was also validated by the volume of rigidity modulus (Mu-Rho) showing high values indicating sands fall within the northeastern part of the field. 展开更多
关键词 Simultaneous Waveform Inversion Lithofacies Fluid Type Rock Physics HYDROCARBON Acoustic Impedance mu-Rho Reservoir
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Eclipse计划系统MU Objective工具在鼻咽癌容积调强放射治疗计划中的应用研究
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作者 陈宗友 曾华驱 +5 位作者 汤树奎 林启富 梁柱 赖春任 赵善辉 温尊北 《中国医学装备》 2023年第10期53-60,共8页
目的:探讨Varian Eclipse计划系统MU Objective工具在鼻咽癌容积调强放射治疗(VMAT)计划中的应用,旨在保证治疗计划质量的同时降低治疗计划的机器跳数(MU)。方法:选取已接受容积调强放射治疗技术的21例鼻咽癌患者,在未使用MU Objective... 目的:探讨Varian Eclipse计划系统MU Objective工具在鼻咽癌容积调强放射治疗(VMAT)计划中的应用,旨在保证治疗计划质量的同时降低治疗计划的机器跳数(MU)。方法:选取已接受容积调强放射治疗技术的21例鼻咽癌患者,在未使用MU Objective工具的情况下给每例患者设计治疗参考计划(MU_(ref));将使用MU Objective工具对MU_(ref)进行重新优化,分别设置MU_(ref)的MU的30%、50%、70%、90%和120%,分别命名为MU_(30%)、MU_(50%)、MU_(70%)、MU_(90%)和MU_(120%)。将治疗计划MU_(30%)、MU_(50%)、MU_(70%)、MU_(90%)和MU_(120%)分别与MU_(ref)进行配对t检验统计分析,比较两种治疗计划的靶区、危及器官(OAR)剂量分布和计划的MU。结果:使用MU Objective工具对参考计划优化MU后,与参考计划相比部分靶区和OAR剂量体积参数差异虽有统计学意义,但无临床意义。治疗计划参数为MU_(30%)、MU_(50%)、MU_(70%)和MU_(90%)时,与MU_(ref)比较计划MU平均分别减少21.5%、19.5%、16.6%和8%,差异有统计学意义(t=9.652,t=8.843,t=8.963,t=11.323;P<0.05)。在MU_(120%)时,治疗计划MU平均增加1.7%,但未显著提高靶区剂量覆盖。结论:对于鼻咽癌VMAT计划,使用Eclipse计划系统的MU Objective工具在减少计划MU的同时可获得与参考计划相似的剂量分布。MU Objective工具可作为鼻咽癌或其他部位VMAT计划的常规使用工具,以保证计划质量同时减少放射治疗计划的MU。 展开更多
关键词 容积调强放射治疗(VMAT) Eclispe计划系统 mu Objective工具 机器跳数(mu)
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Pharmacogenetics of azathioprine in inflammatory bowel disease: A role for glutathione-S-transferase? 被引量:2
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作者 Gabriele Stocco Marco Pelin +6 位作者 Raffaella Franca Sara De Iudicibus Eva Cuzzoni Diego Favretto Stefano Martelossi Alessandro Ventura Giuliana Decorti 《World Journal of Gastroenterology》 SCIE CAS 2014年第13期3534-3541,共8页
Azathioprine is a purine antimetabolite drug commonly used to treat inflammatory bowel disease (IBD). In vivo it is active after reaction with reduced glutathione (GSH) and conversion to mercaptopurine. Although this ... Azathioprine is a purine antimetabolite drug commonly used to treat inflammatory bowel disease (IBD). In vivo it is active after reaction with reduced glutathione (GSH) and conversion to mercaptopurine. Although this reaction may occur spontaneously, the presence of isoforms M and A of the enzyme glutathione-S-transferase (GST) may increase its speed. Indeed, in pediatric patients with IBD, deletion of GST-M1, which determines reduced enzymatic activity, was recently associated with reduced sensitivity to azathioprine and reduced production of azathioprine active metabolites. In addition to increase the activation of azathioprine to mercaptopurine, GSTs may contribute to azathioprine effects even by modulating GSH consumption, oxidative stress and apoptosis. Therefore, genetic polymorphisms in genes for GSTs may be useful to predict response to azathioprine even if more in vitro and clinical validation studies are needed. 展开更多
关键词 Inflammatory bowel disease AZATHIOPRINE PHARMACOGENETICS glutathione-s-transferase Pediatric patients
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Glutathione-S-transferase M1 polymorphisms on the susceptibility to esophageal cancer among three Chinese minorities:Kazakh,Tajik and Uygur 被引量:1
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作者 Xiao-Mei Lu Ting Yang +5 位作者 Shu-Yong Xu Hao Wen Xing Wang Zhi-Hui Ren Yan Zhang Wei Wang 《World Journal of Gastroenterology》 SCIE CAS CSCD 2006年第48期7758-7761,共4页
AIM: To investigate the glutathione-S-transferase M1 (GSTM1) polymorphisms in three Chinese minorities, Kazakh, Uygur, and Tajik; and the pathological significance of GSTM1 polymorphisms in esophageal carcinogenesi... AIM: To investigate the glutathione-S-transferase M1 (GSTM1) polymorphisms in three Chinese minorities, Kazakh, Uygur, and Tajik; and the pathological significance of GSTM1 polymorphisms in esophageal carcinogenesis in Kazakh.METHODS: A total of 1121 blood samples (442 males and 679 females) were obtained from healthy Kazakh (654), Uygur (412) and Tajik (55). Primary esophageal squamous cell cancer (ESCC) tissues from Kazakh were obtained from 116 patients who underwent surgery. GSTM1 polymorphisms were analyzed by a combined approach of PCR and electrophoresis techniques.RESULTS: GSTM1 null genotype was found in 62.63% Uygur, 50.91% Tajik and 47.40% Kazakh. A significantly higher frequency of GSTM1 null genotype in Uygur was observed compared with Kazakh (OR: 1.859, 95% CI: 1.445 -2.391, χ^2 = 23.71, P = 0.000). In addition, GSTM1 null genotype was found in 23.53% of welldifferentiated ESCC in Kazakh, in 49.23% of poorly differentiated ESCC, with a significant difference (OR: 3.152, 95% CI: 1.403-7.080, χ^2 = 8.018, P = 0.007).CONCLUSION: There is a marked difference in the frequency of common GSTM1 null genotype between Uygur and Kazakh. GSTM1 null genotype is associated with differentiation of ESCC in Kazakh. 展开更多
关键词 glutathione-s-transferase M1 KAZAKH UYGUR TAJIK Esophageal cancer
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Glutathione-S-transferases genes-promising predictors of hepatic dysfunction 被引量:3
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作者 Vasyl Prysyazhnyuk Larysa Sydorchuk +5 位作者 Ruslan Sydorchuk Iryna Prysiazhniuk Kateryna Bobkovych Inna Buzdugan Valentina Dzuryak Petro Prysyazhnyuk 《World Journal of Hepatology》 2021年第6期620-633,共14页
diseases pathogenesis are genes that encodes the synthesis of glutathione-Stransferase(GST),known as the second phase enzyme detoxification system that protects against endogenous oxidative stress and exogenous toxins... diseases pathogenesis are genes that encodes the synthesis of glutathione-Stransferase(GST),known as the second phase enzyme detoxification system that protects against endogenous oxidative stress and exogenous toxins,through catalisation of glutathione sulfuric groups conjugation and decontamination of lipid and deoxyribonucleic acid oxidation products.The group of GST enzymes consists of cytosolic,mitochondrial and microsomal fractions.Recently,eight classes of soluble cytoplasmic isoforms of GST enzymes are widely known:α-,ζ-,θ-,κ-,μ-,π-,σ-,andω-.The GSTs gene family in the Human Gene Nomenclature Committee,online database recorded over 20 functional genes.The level of GSTs expression is considered to be a crucial factor in determining the sensitivity of cells to a broad spectrum of toxins.Nevertheless,human GSTs genes have multiple and frequent polymorphisms that include the complete absence of the GSTM1 or the GSTT1 gene.Current review supports the position that genetic polymorphism of GST genes is involved in the pathogenesis of various liver diseases,particularly non-alcoholic fatty liver disease,hepatitis and liver cirrhosis of different etiology and hepatocellular carcinoma.Certain GST allelic variants were proven to be associated with susceptibility to hepatological pathology,and correlations with the natural course of the diseases were subsequently postulated. 展开更多
关键词 glutathione-s-transferase Non-alcoholic fatty liver disease Drug induced liver disease Liver cirrhosis
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Prognostic Significance of Comparison of Clinical Indicators with Manifestations of Genetic Polymorphism of Glutathione-S-Transferases in Non-Small Cell Lung Cancer 被引量:1
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作者 Mikhail N. Shapetska Evelina V. Krupnova +4 位作者 Alena P. Mikhalenka Natalia V. Chebotareva Anna N. Shchayuk Svetlana G. Pashkevich Alexander V. Prokhorov 《Journal of Cancer Therapy》 2018年第12期962-973,共12页
The article presented the results of comparison of polymorphic variants of the genes GSTM1, GSTT1, GSTP1 and clinical manifestations of non-small cell lung carcinoma. The association of the genotype GSTT1 (del) with t... The article presented the results of comparison of polymorphic variants of the genes GSTM1, GSTT1, GSTP1 and clinical manifestations of non-small cell lung carcinoma. The association of the genotype GSTT1 (del) with the risk of developing squamous cell lung cancer has been revealed (OR = 2.54 CI: 1.13 - 5.72, p = 0.035). Analysis of patient survival rate (n = 173) in groups of various histological types of lung cancer showed that in the group of squamous cell lung cancer (n = 91) in patients with genotype GSTT1 (del), the survival rate median was significantly higher—84 months (95% CI 12.4 - 155.7) than in patients with the genotype GSTT1 (+)—36 months (95% CI 25.2 - 46.8, p = 0.045). In contrast, in the adenocarcinoma group (n = 82), the survival rate median in patients with the genotype GSTT1 (del) was 19 months. (95% CI 6.2 - 33.5), and in patients with genotype GSTT1 (+)—67 months (95% CI 50.1 - 84.0), which is the basis for continuing this comparison in an additional group of testees, as the sampling did not achieve the reliability of p = 0.12. Hypothetically, these differences may be due to differences in the gender composition of squamous cell lung cancer and adenocarcinoma and the involvement of GST enzymes in the metabolism of estrogens in adenocarcinoma in women and other hormonal background and reactivity of the male body with squamous cell carcinoma. Further research and subsequent analysis of the results will be aimed at confirming this hypothesis. 展开更多
关键词 SQUAMOUS Cell Lung Carcinoma ADENOCARCINOMA glutathione-s-transferase Survival Rate
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Evaluation of Glutathione-S-transferase and ceruloplasmin levels in gingival crevicular fluid and gingival tissue as diagnostic markers for chronic periodontitis 被引量:1
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作者 Jothi. M. Varghese Vinutha Bhat +1 位作者 G. S. Bhat Namita Rao 《Advances in Bioscience and Biotechnology》 2012年第4期437-441,共5页
Periodontitis, is an infectious ailment of multifactorial origin, that brings about destruction of bone and surrounding tissues. There are various oral pathogens that may be responsible for the destruction. The host e... Periodontitis, is an infectious ailment of multifactorial origin, that brings about destruction of bone and surrounding tissues. There are various oral pathogens that may be responsible for the destruction. The host encounters these microbial invasions and their products by the production and release of inflammatory mediators from the cells within the body. Glutathione-S-transferase (GST) are a group of enzymes that utilize glutathione in conditions resulting in oxidative stress. These enzymes play a key role in the detoxifycation of such substance. It aids in preventing damage to important cellular components caused by release of free reactive oxygen species. Ceruloplasmin is a ferroxidase enzyme. It plays a role as an anti-inflammatory agent, by its ability to scavenge free radicals within the body. The present study was targeted at evaluating the levels of Glutathione-S-Transferase (GST) and Ceruloplasmin as diagnostic markers for patients with chronic periodontitis in gingival crevicular fluid (GCF) and the gingival tissues. Thirty patients were divided into two groups. Experimental group comprising of 15 subjects with chronic perio- dontitis and the control group was composed of 15 healthy individuals. Highly significant changes in GST between the diseased and normal patients (P = 0.001) were detected. There was a decrease in GST level in both gingival tissue & GCF in diseased patients when compared to the control patients. The ceruloplasmin levels in GCF and gingival tissues showed no difference between the control and diseased group. Hence,these results indicate a relationship suggesting that GST produced during chronic inflammation could be used as biomarker that indicate periodontal disease . 展开更多
关键词 glutathione-s-transferase CERULOPLASMIN GCF GINGIVAL TISSUES Chronic PERIODONTITIS
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基于新浪微博数据的东航MU5735坠毁事件舆情热度演化及情感分析 被引量:1
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作者 岳扬 山成虎 +3 位作者 彭春霖 郑小琳 闫玉玺 谷琼 《计算机时代》 2023年第2期55-60,共6页
采用一种结合关键词提取和机器学习的情感分析方法对东航MU5735坠毁事件相关的部分微博数据进行情感分析,统计、分析坠机事件发生后的微博热搜话题数据。研究发现,东航MU5735坠毁事件的舆情热度演化整体上遵守生命周期理论,不过该类突... 采用一种结合关键词提取和机器学习的情感分析方法对东航MU5735坠毁事件相关的部分微博数据进行情感分析,统计、分析坠机事件发生后的微博热搜话题数据。研究发现,东航MU5735坠毁事件的舆情热度演化整体上遵守生命周期理论,不过该类突发性网络舆情通常表现为热度迅速升高,舆情迅速进入成长期和爆发期,潜伏期往往很短。公众对该事件以中性情感为主,消极情感次之。本文还结合传播学、心理学、社会学、统计学多角度对舆情进行解读。 展开更多
关键词 东航mu5735坠毁事件 新浪微博 舆情分析 情感分析 舆情演化
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适配器相关蛋白复合物1亚基Mu2在结肠癌中的表达及临床意义
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作者 张鑫 汪刘华 +1 位作者 苗永昌 王道荣 《实用临床医药杂志》 CAS 2023年第9期59-64,共6页
目的探讨适配器相关蛋白复合物1亚基Mu2(AP1M2)表达与结肠癌患者临床病理特征的相关性。方法收集2017年1-12月连云港市第二人民医院行根治性手术治疗的97例结肠恶性肿瘤患者的癌组织及癌旁组织。收集患者临床病理特征资料,采用免疫组化... 目的探讨适配器相关蛋白复合物1亚基Mu2(AP1M2)表达与结肠癌患者临床病理特征的相关性。方法收集2017年1-12月连云港市第二人民医院行根治性手术治疗的97例结肠恶性肿瘤患者的癌组织及癌旁组织。收集患者临床病理特征资料,采用免疫组化法检测结肠癌组织与癌旁组织中AP1M2蛋白的表达水平,采用酶联免疫吸附测定法检测AP1M2在血清中表达情况。分析AP1M2蛋白表达与结肠恶性肿瘤患者临床病理特征的关系;采用Kaplan-Meier法分析结肠癌患者术后5年生存情况的影响因素;采用生物信息学分析AP1M2涉及的蛋白及相关通路情况。结果免疫组化分析发现,AP1M2在结肠癌组织中的表达高于癌旁组织;在97对标本中,结肠癌组织AP1M2高表达73例,癌旁组织AP1M2高表达43例,差异有统计学意义(P=0.004)。酶联免疫吸附测定法检测发现,结肠癌患者癌组织血清中AP1M2表达高于癌旁组织,差异有统计学意义(P=0.02)。肿瘤直径>5 cm、N_(1)~N_(2)分期(有淋巴结转移)、T分期的T_(3)~T_(4)期、术后5年复发患者AP1M2高表达比率分别高于肿瘤直径≤5 cm、N_(0)分期(无淋巴结转移)、T分期的T_(1)~T_(2)期、术后5年无复发患者,差异有统计学意义(P<0.05)。术后随访5年,24例AP1M2低表达患者术后5年死亡5例,而73例AP1M2高表达患者术后5年死亡24例,差异有统计学意义(P=0.005)。Cox分析显示,AP1M2是结肠癌患者术后死亡的危险因素。生物学分析显示,AP1M2与肿瘤代谢及黏附相关。结论AP1M2表达水平在结肠癌组织中及血清中上调,这与肿瘤临床分期、淋巴结转移情况相关,与结肠癌患者预后也相关。AP1M2可作为结肠癌预后的潜在预测指标。 展开更多
关键词 结肠癌 适配器相关蛋白复合物1亚基mu2 病理特征 危险因素 生存期 预后
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Modification of the Genetic Polymorphism of Glutathione-S-Transferase (GSTM1 and GSTT1) in Motorcycle Drivers Exposed to BTEX in Cotonou
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作者 Cachon Fresnel Boris Sagbo H. Firmin +4 位作者 Nanoukon Chimène Djedatin Gustave Atindehou Ménonvè Senou Maximin Ayi-Fanou Lucie 《Journal of Biosciences and Medicines》 CAS 2022年第11期104-112,共9页
The glutathione-S-transferase genes mainly the GSTM1 and GSTT1 alleles are responsible for the synthesis of detoxication enzymes that can remove toxic substances. The objective of this study is to seek changes in the ... The glutathione-S-transferase genes mainly the GSTM1 and GSTT1 alleles are responsible for the synthesis of detoxication enzymes that can remove toxic substances. The objective of this study is to seek changes in the genetic polymorphism of glutathione-S-transferase GSTM1 and GSTT1 in motorcycle drivers exposed to BTEX. Our study group consists of 60 motorcycle drivers including 30 professional and 30 non-professional. Blood samples were preleveled from the study population in the EDTA tubes and DNA was extracted by the phenol/chloroform method. The PCR technique was used to determine the presence or absence of genes. Our results showed that the percentage of GSTM1 null genotype has a statistically significant difference (P = 0.02), while the percentage of GSTT1 null genotype was non-significant (P = 0.76) between the two groups. The percentage of deletion of both genes is higher in professional than non-professional motorcycle drivers. Air pollution in Cotonou by BTEX seems to influence the deletion of the GSTM1 and GSTT1 genes at a higher percentage among professional than non-professional motorcycle drivers. 展开更多
关键词 BTEX glutathione-s-transferase Deletion PCR Motorcycle Drivers
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Carboxylesterase and Glutathione-S-Transferase (GST's) Induced Resistance to Bacillus thuringiensis Toxin CrylAb in Rice Leaf Folder, Cnaphalocrocis medinalis (Guenee) Populations
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作者 Veegala Ramesh Babu Vemuri Shashi Bhushan +3 位作者 Chintalapati Padmavathy: Muthugonder Mohan SenaMahendran. Balachandran Bellamkonda Ramesh 《Journal of Agricultural Science and Technology(A)》 2013年第1期53-59,共7页
The rice leaf folder (RLF), Cnaphalocrocis medinalis (Guenee) (lnsecta: Lepidoptera: Pyralidae), is an important pest, widely distributed in many rice growing areas of Asia. The over-use of broad-spectrum chem... The rice leaf folder (RLF), Cnaphalocrocis medinalis (Guenee) (lnsecta: Lepidoptera: Pyralidae), is an important pest, widely distributed in many rice growing areas of Asia. The over-use of broad-spectrum chemical insecticides has been cited as a major cause of outbreaks of C. medinalis as excessive spraying of insecticide disrupts natural biological control insecticides still remain the major control tactics against leaf folder. Carbofuran and fenthion, bendiocarb, acephate, carbosulfan, quinolphos, monocrotophos, phosphamidon and fenvalerate are the common ones used against rice leaf folder. Genetically, modified rice lines expressing B. thuringiensis insecticidal crystal proteins produced are highly tolerant to leidopteran pests. Though economic and environmental benefits of GM crops is well established, the matter of concern is the possibility of target insect pest developing resistance to this B. thuringiensis insecticidal toxins, evident from many laboratory and field experiments against many insect pests. The involvement of GSH S-transferase, carboxylesterase, and microsomal monooxygenase in insecticide resistance has been reported in insecticide-resistant strains of many insect species. Hence, the present study was taken up to monitor for cross resistance between B. thuringiensis cry toxins and synthetic insecticides in larvae of leaf folder as it is mediated by carboxylesterase titre and other enzymes by bioassay for two selected rice leaf folder field populations at the Entomology division of Directorate of Rice Research which showed 2-fold resistance ratio. Qualitative and quantitative changes of carboxylesterase (CarE) and glutathione-s-transferase (GST's) were worked out with midguts extracts of the two C. medinalis populations in the presence of a-napthyl acetate and chlorodi-nitro benzene substrates. 展开更多
关键词 Cnaphalocrocis medinalis carboxylesterase and glutathione-s-transferase ISOZYMES B type esterases.
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