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THERMAL DECOMPOSITION BEHAVIOR OF AMMONIUM THIO TUNGSTATE in H_2 被引量:1
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作者 P. F. Xing , L. F. Ma , K. Quan and Y. C. Zhai School of Materials and Metallurgy , Northeastern University , Shenyang 110006 , China 《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 1999年第5期1171-1174,共4页
The ther m al deco m position mechanism of a m m oniu m thiotungstate of the size of 63 ~75 μmin H2 has been investigated by D T A and X R D methods . The ther m al deco m position activationenergies and the ord... The ther m al deco m position mechanism of a m m oniu m thiotungstate of the size of 63 ~75 μmin H2 has been investigated by D T A and X R D methods . The ther m al deco m position activationenergies and the orders of a m m oniu m thiotu ngstate were calculated by means of Kissinger , Freem an Carroll and Coast Redfern m ethods . It w as also obtained that therm al deco m posi tion is cond ucted according to four reaction equations :( N H4) 2 W S4· H2 O(s) ( N H4) 2 W S4(s) + H2 O(g) W S2(s) + 2 N H3(g) + H2(g) + 2 S(s) + H2 O(g) W S2(s) + 2 N H3(g) + 2 H2 S(g) + H2 O(g) W S2(s) + W(s) + 2 N H3(g) + 2 H2 S(g) + H2 O(g) . 展开更多
关键词 a m moniu m thiotungstate ther m al deco m position W S2 H2
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Chemical Composition of Pellonula leonensis Fish Oils from the Congo River Obtained by Soxhlet Extraction
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作者 Bob Wilfrid Loumouamou Léa Béatrice Mambou Gadet Michel Dzondo 《Open Journal of Applied Sciences》 2024年第8期2112-2123,共12页
The chemical composition of Pellonula leonensis fish oils from the Congo River (at Boko city) was carried out. The fatty acids were determined by gas chromatography. The Sn-2 position of fatty acids on glycerol was ca... The chemical composition of Pellonula leonensis fish oils from the Congo River (at Boko city) was carried out. The fatty acids were determined by gas chromatography. The Sn-2 position of fatty acids on glycerol was carried out by the ISO 6800 standard. The separation of the compounds (as free fatty acids, monoglycerides, diglycerides, triglycerides, sterols and methyl esters, etc.) was carried out by HPLC using gel permeation with refractometric detection. The phospholipid composition was by HPLC with an evaporative light scattering detector. We obtained oil contents of 32.10 (±0.46)%. The major fatty acids were Palmitic acid (27.41%) and oleic acid (24.23%). The SFA were of 44.50%. The MUFA represent 32.54% and PUFA 22.60%. Regarding the Sn-2 position on glycerol, 48.0% were by SFA and 51.3% were by unsaturated fatty acids. Among them 34.2% of fatty acids were 17.5% oleic acid molecules, 3.3% DHA molecules and 2.1% EPA molecules. Free fatty acids have contents of more than 62%, Diglycerides 16.63% and triglycerides 20.46%. Seven different phospholipids were identified, namely: Phosphatidylglycerol (PG), Phosphatidylethanolamine (PE), Phosphatidylinositol (PI), Phosphatidylcholine (PC), Sphingomyelin (SM), Lyso Phosphatitdylcholine (LPC) and Lyso Phosphatidylethanolamine (LPE). According to the high levels in position 2 of the glycerol of palmitic acid, the consumption of Pellonula leonensis fish could be moderate. 展开更多
关键词 Pellonula leonensis Fatty Acids Sn-2 position TRIACYLGLYCEROL Phospholopids
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Average position in quantum walks with a U(2) coin
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作者 李敏 张永生 郭光灿 《Chinese Physics B》 SCIE EI CAS CSCD 2013年第3期40-43,共4页
We investigated discrete-time quantum walks with an arbitary unitary coin.Here we discover that the average position x=max(x) sin(α+γ),while the initial state is 1/2~(1/2)(|0L+i|0R).We verify the result... We investigated discrete-time quantum walks with an arbitary unitary coin.Here we discover that the average position x=max(x) sin(α+γ),while the initial state is 1/2~(1/2)(|0L+i|0R).We verify the result,and obtain some symmetry properties of quantum walks with a U(2) coin with |0L and |0R as the initial state. 展开更多
关键词 quantum random walk U(2 coin average position
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SYNTHESIS OF ADENOSINE DERIVATIVES WITH CARBOXYALKYL SIDE CHAIN AT 2',3'OR 5'POSITION
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作者 Zeng Li SONG Jun Dong ZHANG Li He ZHANG School of Pharmaceutical Sciences,Beijing Medical University,Beijing 100083. 《Chinese Chemical Letters》 SCIE CAS CSCD 1993年第12期1053-1056,共4页
Some nucleoside carhoxylic acid derivatives,such as(±)ethyl ester of griseolic acid (4)and 9-(2'-deoxy-2'-(benzyloxycarbonyl)-methylene-β-D-rihohept-2'-enofuranosyluranate)adenine (11),were synthesiz... Some nucleoside carhoxylic acid derivatives,such as(±)ethyl ester of griseolic acid (4)and 9-(2'-deoxy-2'-(benzyloxycarbonyl)-methylene-β-D-rihohept-2'-enofuranosyluranate)adenine (11),were synthesized.The formation of lactone of 5'-deoxy-adenosineacetic acid(AAA,3)was investigated by using different reagents for lactonization from AAA,but all of the efforts failed, and sone unexpected compounds were obtained. 展开更多
关键词 DMSO HNMR 亚砜 FAB OR 5’position SYNTHESIS OF ADENOSINE DERIVATIVES WITH CARBOXYALKYL SIDE CHAIN AT 2 AT
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Hybrid H_2/H_∞ force/position control based on neural networks
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作者 温淑焕 蔡建羡 王洪瑞 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2004年第5期569-572,共4页
A neural network control scheme with mixed H2/H∞performance was proposed for robot force/position control under parameter uncertainties and external disturbances. The mixed H2/H∞tracking performance ensures both rob... A neural network control scheme with mixed H2/H∞performance was proposed for robot force/position control under parameter uncertainties and external disturbances. The mixed H2/H∞tracking performance ensures both robust stability under a prescribed attenuation level for external disturbance and H2optimal tracking. The neural network was introduced to adaptively estimate nonlinear uncertainties, improving the system’s performance under parameter uncertainties as well as obtaining the H2/H∞tracking performance. The simulation shows that the control method performs better even when the system is under large modeling uncertainties and external disturbances. 展开更多
关键词 ROBOTICS force/position control mixed H_2/H_∞control neural networks
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不同厂家热电池FeS_(2)-CoS_(2)复合正极材料的比较研究
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作者 冯帅 张纯 +4 位作者 彭振国 孙现忠 刘岁鹏 史紫阳 杨军 《火工品》 CAS 北大核心 2025年第1期77-82,共6页
为了加快热电池FeS_(2)-CoS_(2)复合正极材料的优化及应用,采用两种不同厂家生产的CoS_(2)作为导电剂添加到FeS_(2)中,制备出FeS_(2)-CoS_(2)复合正极材料及其单体电池,并对两种CoS_(2)原材料、FeS_(2)-CoS_(2)复合正极材料的微观形貌... 为了加快热电池FeS_(2)-CoS_(2)复合正极材料的优化及应用,采用两种不同厂家生产的CoS_(2)作为导电剂添加到FeS_(2)中,制备出FeS_(2)-CoS_(2)复合正极材料及其单体电池,并对两种CoS_(2)原材料、FeS_(2)-CoS_(2)复合正极材料的微观形貌、粒度分布、X射线衍射分析以及单体电池的放电性能进行了研究。结果表明,广东产的FeS_(2)-CoS_(2)正极材料具有更均匀的微观分布和较少的小粒度粒子,湖南产的FeS_(2)-CoS_(2)正极材料更适合小电流放电应用,而广东产的FeS_(2)-CoS_(2)正极材料更适合于高功率放电。此外,将两种FeS_(2)-CoS_(2)正极材料应用于某型号热电池并进行高低温放电测试,结果表明广东产的FeS_(2)-CoS_(2)正极材料在放电性能上优于湖南产的FeS_(2)-CoS_(2)正极材料。 展开更多
关键词 热电池 正极材料 FeS_(2) CoS_(2) 微观形貌 放电性能
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The Expression of Apoptosis-Related Genes Bcl-2 and Bax Protein and Apoptosis Positivity in Cervical Carcinoma during Irradiation
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作者 赵东利 石景森 +2 位作者 李明众 宋丽萍 王书文 《The Chinese-German Journal of Clinical Oncology》 CAS 2005年第2期105-107,共3页
To evaluate the apoptosis positivity, the expression of Bcl-2, bax proteinsin 30 patients with squamous cell cervix carcinoma before and after radiotherapy. Methods: By usingimmuno-histochemical and TDT-dUTP nick end ... To evaluate the apoptosis positivity, the expression of Bcl-2, bax proteinsin 30 patients with squamous cell cervix carcinoma before and after radiotherapy. Methods: By usingimmuno-histochemical and TDT-dUTP nick end labelling techniques, 30 cases of squamous cell cervicalcarcinoma were analyzed. Results: The apoptosis positivity before and after irradiation was 76.7%and 100% respectively, with the difference being significant (P 【 0.05); The positive rates of Bcl-2protein before and after irradiation were 73.3% and 46.7% respectively, with the difference beingsignificant (P 【 0.05); The positive rates of bax protein before and after irradiation were 86% and100% respectively, with the difference being significant (P 【 0.05). Conclusion: bax and Bcl-2protein play an important role in apoptosis induced by fractionated radiation therapy. Apoptosisinduced by irradiation is contributed to upregulation of bax protein or downregulation of Bcl-2protein. 展开更多
关键词 cervical carcinoma RADIOTHERAPY apoptosis positivity bcl-2 protein baxprotein
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伊尼妥单抗治疗人表皮生长因子受体2阳性转移性乳腺癌伴胃肠功能紊乱1例
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作者 朱莉丽 付马墨阳 +3 位作者 鲁磊 刘湘晨 尚宏清 王冰涛 《中国当代医药》 CAS 2024年第3期24-28,共5页
乳腺癌是女性常见的肿瘤,如今乳腺癌实体肿瘤通过相应的治疗可取得较好的疗效,但人表皮生长因子受体2(HER2)阳性乳腺癌侵袭性较强、恶性程度高,需引起患者及医务人员的重视。本文回顾性分析1例激素受体阴性、HER2阳性伴胃肠功能紊乱的... 乳腺癌是女性常见的肿瘤,如今乳腺癌实体肿瘤通过相应的治疗可取得较好的疗效,但人表皮生长因子受体2(HER2)阳性乳腺癌侵袭性较强、恶性程度高,需引起患者及医务人员的重视。本文回顾性分析1例激素受体阴性、HER2阳性伴胃肠功能紊乱的乳腺癌患者诊治经过。患者初诊为局部晚期炎症乳腺癌伴腋窝淋巴结转移,给予新辅助化疗及手术治疗。术后3年后病情进展,予以伊尼妥单抗联合白蛋白紫杉醇,后续伊尼妥单抗单独靶向治疗,病情持续缓解。提示对于HER2阳性晚期乳腺癌,伊尼妥单抗是个很好的单抗类药物选择。 展开更多
关键词 伊尼妥单抗 转移性乳腺癌 胃肠功能紊乱 人表皮生长因子受体2阳性
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CTCS-2+ATO列控系统对短站坪长度需求适应性研究
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作者 张敏慧 张伟 +2 位作者 刘长波 宋睿 全宏宇 《铁道工程学报》 EI CSCD 北大核心 2024年第2期74-79,共6页
研究目的:对于有地下线路的铁路工程,由于开挖土方等方面的问题,要求站坪长度尽量缩短,以节省工程投资。现有CTCS-2+ATO列控系统因其安全防护距离设置位置、车载设备安装位置、适应的运行速度较高等原因,对站坪长度要求较CBTC列控系统长... 研究目的:对于有地下线路的铁路工程,由于开挖土方等方面的问题,要求站坪长度尽量缩短,以节省工程投资。现有CTCS-2+ATO列控系统因其安全防护距离设置位置、车载设备安装位置、适应的运行速度较高等原因,对站坪长度要求较CBTC列控系统长,成为在市域铁路运用时的不利因素,需要对其进行短站坪长度需求的适应性分析并提出适宜的解决方法,提升系统的竞争力。研究结论:(1)侧线股道增设安全线,基于列车停稳信息及时解锁过走防护区段、利用应答器报文增加过走防护区段信息、及时回缩列控移动授权范围等配套方法,将安全距离、附加距离设于目标点信号机的内方,利用安全线及咽喉区线路缩短股道区线路长度;(2)合理约束车载应答器接收天线安装位置,根据市域列车运行速度计算、确定可靠解析出报文所需要的应答器距离信号机距离,以及应答器组间最小距离要求,最终确定股道出站应答器安装位置最小长度需求;(3)经折返线道岔侧向的进路不发低频码,轨道电路长度仅考虑轨道占用检查时间,进一步缩短折返道岔区段长度要求;(4)本研究成果在市域铁路中有广阔的运用前景。 展开更多
关键词 CTCS-2+ATO 短站坪长度 安全距离 设置位置
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磷脂酶A_2氨基末端衍生肽的合成及其抗细菌活性的研究
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作者 安娜 李艳 +1 位作者 廖柳凤 梁宁生 《中国医药导报》 CAS 2024年第10期24-27,共4页
目的 探讨磷脂酶A_(2)(PLA_(2))氨基末端衍生肽的合成及抗菌活性。方法 根据PLA_(2)氨基末端氨基酸残基的顺序合成为多肽PLA_(2)N_(11)、PLA_(2)N_(15)、PLA_(2)N_(20),将其分别与2种细菌(大肠埃希菌、枯草杆菌)在特定条件下培养,并以... 目的 探讨磷脂酶A_(2)(PLA_(2))氨基末端衍生肽的合成及抗菌活性。方法 根据PLA_(2)氨基末端氨基酸残基的顺序合成为多肽PLA_(2)N_(11)、PLA_(2)N_(15)、PLA_(2)N_(20),将其分别与2种细菌(大肠埃希菌、枯草杆菌)在特定条件下培养,并以生理盐水作为对照,分析抗菌活性。结果 与对照比较,多肽不同作用浓度时PLA_(2)N_(11)、PLA_(2)N_(15)、PLA_(2)N_(20)对革兰氏阳性枯草杆菌杀菌活性更强,各多肽间比较,差异有统计学意义(P<0.05);当多肽作用浓度为500μg/ml时,PLA_(2)N_(15)对革兰氏阳性枯草杆菌杀菌活性可达99.8%,高于PLA_(2)N_(11)、PLA_(2)N_(20),及对照(P<0.05)。与对照比较,各多肽不同作用浓度时对大肠埃希菌杀菌活性比较,差异有统计学意义(P<0.05);多肽作用浓度为7.81、125.00、500.00μg/ml时,PLA_(2)N_(15)的杀菌活性均高于PLA_(2)N_(11)和PLA_(2)N_(20),及对照(P<0.05);多肽作用浓度为31.25μg/ml时,PLA_(2)N_(15)的杀菌活性低于PLA_(2)N_(11)的杀菌活性,且高于PLA_(2)N_(20)的杀菌活性(P<0.05)。结论 多肽PLA_(2)N_(11)、PLA_(2)N_(15)、PLA_(2)N_(20)对枯草杆菌、大肠埃希菌有很强的杀菌作用。 展开更多
关键词 磷脂酶A_2氨基末端衍生肽 抗菌活性 革兰氏阳性菌 革兰氏阴性菌
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曲妥珠单抗联合化疗致人表皮生长因子受体2阳性乳腺癌患者心脏毒性的影响因素分析
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作者 陈永刚 赵恒毅 孙雯霏 《中医临床研究》 2024年第6期101-105,共5页
目的:探讨曲妥珠单抗联合化疗致人表皮生长因子受体2(Human Epidermal Growth Factor Receptor-2,HER-2)阳性乳腺癌患者心脏毒性的影响因素。方法:选取2020年12月-2022年12月徐州市中心医院诊治的152例HER-2阳性乳腺癌患者为研究对象。... 目的:探讨曲妥珠单抗联合化疗致人表皮生长因子受体2(Human Epidermal Growth Factor Receptor-2,HER-2)阳性乳腺癌患者心脏毒性的影响因素。方法:选取2020年12月-2022年12月徐州市中心医院诊治的152例HER-2阳性乳腺癌患者为研究对象。所有患者均采用曲妥珠单抗联合化疗(AC→PH)方案治疗,治疗期间每3个月使用超声监测心功能,统计心脏毒性发生情况。收集患者的临床资料,包括年龄、体质量指数、肿瘤分期、合并症(高血压病、糖尿病、高脂血症)、雌激素受体(Estrogen Receptor,ER)/孕激素受体(Progesterone Receptor,PR)的表达情况、吸烟史、饮酒史、同期行放疗及右丙亚胺使用情况,采用单因素分析、多因素Logistic回归分析患者发生心脏毒性的危险因素。结果:152例患者中心脏毒性发生率为26.31%,发生心脏毒性的患者常见的心电图改变有:T波改变、窦性心率过缓/过速、ST段异常等。单因素分析显示,年龄≥60岁、合并高血压病、合并高脂血症、同期行放疗、联合使用右丙亚胺是发生心脏毒性的影响因素(P <0.05)。多因素Logistic回归分析显示,年龄[95%置信区间(CI):2.429~5.135]、合并高血压病(95%CI:1.625~3.962)、合并高脂血症(95%CI:2.054~5.362)、同期行放疗(95%CI:1.759~4.637)是曲妥珠单抗联合化疗致HER-2阳性乳腺癌患者心脏毒性的危险因素(P<0.05),而联合使用右丙亚胺(95%CI:3.772~6.015)可显著减少心脏毒性的发生(P <0.05)。结论:年龄≥60岁、合并高血压病/高脂血症、同期行放疗是曲妥珠单抗联合化疗致HER-2阳性乳腺癌患者心脏毒性发生的危险因素,使用右丙亚胺是HER-2阳性乳腺癌患者发生心脏毒性的保护因素;化疗期间应将年龄≥60岁、合并高血压病和高脂血症、同期行放疗的患者列为心脏毒性的重点防治人群,联合应用右丙亚胺有助于减少心脏毒性发生。 展开更多
关键词 曲妥珠单抗 化疗 人表皮生长因子受体2阳性乳腺癌 心脏毒性 因素分析
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c-Fos enhances the survival of thymocytes during positive selection by upregulating Bcl-2 被引量:2
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作者 Xiaoming Wang Yafeng Zhang +2 位作者 Gang Xiao Xiang Gao Xiaolong Liu 《Cell Research》 SCIE CAS CSCD 2009年第3期340-347,共8页
T cells are derived from progenitor thymocytes, of which only a minority receive the appropriate TCR signal, undergo positive selection and mature. Owing to the very short lifespan of thymocytes, the prerequisite for ... T cells are derived from progenitor thymocytes, of which only a minority receive the appropriate TCR signal, undergo positive selection and mature. Owing to the very short lifespan of thymocytes, the prerequisite for posi- tive selection is survival. TCR signal-induced Bcl-2 expression is believed to play a dominant role in the survival of positively selecting thymocytes, but how Bcl-2 is directly regulated is unknown. Here we report that the immediate early gene (IEG) c-Fos can stimulate the expression of Bcl-2, depending on a specific AP-l-binding site in the Bcl-2 promoter. In c-Fos transgenic (Fos-Tg) mice, c-Fos binds to this site and promotes the expression of Bcl-2. As a result, Fos-Tg thymocytes exhibited enhanced survival, and more mature single-positive (SP) thymocytes were generated, even on a unique TCR background. The TCR repertoire remained normal in Fos-Tg mice. Our results identified c-Fos as the mediator of the stimulatory effect of TCR signaling on Bcl-2 expression. Therefore, c-Fos, as an IEG, because of its early response ability, can quickly rescue the survival of short-lived thymocytes during positive selection. Our results provide novel insight into the mechanism regulating the survival of positively selecting thymocytes. 展开更多
关键词 C-FOS BCL-2 SURVIVAL thymocyte development positive selection
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阿贝西利联合非甾体类芳香化酶抑制剂一线治疗HR+/HER2-绝经后晚期乳腺癌患者的效果观察
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作者 陈燕红 王玮 +2 位作者 刘玉娟 覃清清 黄江昌 《科技与健康》 2024年第15期113-116,共4页
探讨针对激素受体阳性/人类表皮生长因子受体2阴性(HR+/HER2-)绝经后晚期乳腺癌患者应用阿贝西利联合非甾体类芳香化酶抑制剂一线治疗的效果。以玉林市红十字会医院在2022年1月—2023年4月收治的92例HR+/HER2-绝经后晚期乳腺癌患者为研... 探讨针对激素受体阳性/人类表皮生长因子受体2阴性(HR+/HER2-)绝经后晚期乳腺癌患者应用阿贝西利联合非甾体类芳香化酶抑制剂一线治疗的效果。以玉林市红十字会医院在2022年1月—2023年4月收治的92例HR+/HER2-绝经后晚期乳腺癌患者为研究对象,采用随机数字表法将其分为对照组(n=46,应用非甾体类芳香化酶抑制剂一线治疗)和研究组(n=46,在对照组基础上应用阿贝西利治疗),对比两组疗效、不良反应发生率、生活质量。研究发现,针对HR+/HER2-绝经后晚期乳腺癌患者应用阿贝西利联合非甾体类芳香化酶抑制剂一线治疗,疗效有所提高,不良反应未增加,安全性较高,患者生活质量显著提高,值得推广。 展开更多
关键词 激素受体阳性 晚期乳腺癌 阿贝西利 人类表皮生长因子受体2阴性
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Effect of basic fibroblast growth factor and danshen on bcl-2 and p53 mRNA expression in the brain of rats exposed to repeated, high, positive acceleration (+Gz)
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作者 Hongjin Liu Qing Cai 《Neural Regeneration Research》 SCIE CAS CSCD 2008年第7期747-750,共4页
BACKGROUND: Both animal experiments and clinical studies have shown that basic fibroblast growth factor (bFGF) and danshen (Salvia miltiorrhiza) can exhibit protective effects on ischemia-reperfusion cerebral inj... BACKGROUND: Both animal experiments and clinical studies have shown that basic fibroblast growth factor (bFGF) and danshen (Salvia miltiorrhiza) can exhibit protective effects on ischemia-reperfusion cerebral injury. OBJECTIVE: To test whether bFGF and danshen can protect cerebral injury induced by exposure to repeated, high, positive acceleration (+Gz) in an animal model and to analyze the possible mechanisms. DESIGN, TIME AND SETTING: Randomized controlled animal study. The experiment was performed at the Research Center for Molecular Biology, Air-force General Hospital of Chinese PLA from April to August 2000. MATERIALS: A total of 20 clean grade, healthy, Sprague Dawley rats of both genders, weighing (200 ± 15) g, were provided by our experimental animal center. Rats were randomly divided into 5 groups: the control group, +Gz exposure group, bFGF group, danshen group, and saline group, with 4 animals per group. bFGF (Beijing Bailuyuan Biotechnology Co. Ltd.) and danshen solution (Shanghai Zhongxi Pharmaceutical Co. Ltd.) were used. METHODS: All rats were fixed on a rotary arm of a centrifugal apparatus (2 m in radius) with their heads oriented towards the center of the apparatus. Except for rats in the control group, the value of +Gz exposure was +14 Gz with an acceleration rate of 1.5 G/s. The peak force lasted for 45 seconds. +Gz exposure was performed three times with intervals of 30 minutes. Rats in the control group received the same +Gz procedure, but the G value was +1 Gz. Rats in bFGF group and danshen group were intraperitoneally injected with 100 μg/kg bFGF or 15 g/kg danshen solution, respectively, at 30 minutes prior to centrifugation and immediately after centrifugation. Rats in saline group were injected with the same volume of saline. Six hours after exposure, rats were decapitated. One hemisphere was preserved in liquid nitrogen for RNA extraction and the other was processed for apoptosis detection. MAIN OUTCOME MEASURES: mRNA levels of bcl-2 and p53 were measured by semi-quantitative reverse-transcription polymerase chain reaction. Apoptotic cell death was detected by terminal deoxynuleotidyl transferase-mediated dUTP nick end labeling. RESULTS: Changes in mRNA expression of bcl-2 and p53 and apoptotic cells were observed in rat brain six hours after repeated +Gz exposures, bFGF and danshen were able block the changes of bcl-2 and p53 expression and inhibit apoptotic cell death. CONCLUSION: The data suggest that apoptosis and changes in bcl-2 and p53 expression in the rat brain can be induced by repeated +Gz exposures. Apoptosis is, therefore, one of the molecular mechanisms of brain damage induced by repeated +Gz exposures, bFGF and danshen were of the equal potency in preventing brain injury induced by repeated +Gz exposures. 展开更多
关键词 positive acceleration RATS apoptosis BCL-2 P53 gene expression basic fibroblast growth factor DANSHEN
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Coexistence of positive and negative magnetic entropy changes in CeMn_2(Si_(1-x)Ge_x)_2 compounds
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作者 左文亮 胡凤霞 +1 位作者 孙继荣 沈保根 《Chinese Physics B》 SCIE EI CAS CSCD 2015年第9期444-447,共4页
A series of CeMn2(Si1-xGex)2(x = 0.2, 0.4, 0.6, 0.8) compounds are prepared by the arc-melting method. All the samples primarily crystallize in the Th Cr2Si2-type structure. The temperature dependences of zero-fie... A series of CeMn2(Si1-xGex)2(x = 0.2, 0.4, 0.6, 0.8) compounds are prepared by the arc-melting method. All the samples primarily crystallize in the Th Cr2Si2-type structure. The temperature dependences of zero-field-cooled(ZFC) and FC magnetization measurements show a transition from antiferromagnetic(AFM) state to ferromagnetic(FM) state at room temperature with the increase of the Ge concentration. For x = 0.4, the sample exhibits two kinds of phase transitions with increasing temperature: from AFM to FM and from FM to paramagnetic(PM) at around TN-197 K and T C-300 K,respectively. The corresponding Arrott curves indicate that the AFM–FM transition is of first-order character and the FM–PM transition is of second-order character. Meanwhile, the coexistence of positive and negative magnetic entropy changes can be observed, which are corresponding to the AFM–FM and FM–PM transitions, respectively. 展开更多
关键词 magnetocaloric effect CeMn2(Si0.6Ge0.4)2 compound metamagnetic transition positive entropy change
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Current status of PI3K-mTOR inhibition in hormone-receptor positive, HER2-negative breast cancer
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作者 Navid Sobhani Daniele Generali +2 位作者 Fabrizio Zanconati Marina Bortul Bruna Scaggiante 《World Journal of Clinical Oncology》 CAS 2018年第8期172-179,共8页
Breast cancer (BC) is the most common cancer in women and second only to lung cancer in terms of mortality. Among the three different BC subtypes, the oestrogen receptor positive represents nearly 70% of all cases and... Breast cancer (BC) is the most common cancer in women and second only to lung cancer in terms of mortality. Among the three different BC subtypes, the oestrogen receptor positive represents nearly 70% of all cases and it is usually treated with anti-oestrogen drugs. However, the majority of hormone receptor positive metastatic BC patients develop resistance to anti-oestrogen treatments.The need for more down-stream therapies brought to the development of therapeutic strategies inhibiting the phosphatidylinositol 3-kinase-mammalian target of rapamycin (mTOR) pathway. Inhibitors of the mTOR have been tested in different clinical trials; everolimus has been Food and Drug Administration approved for the treatment of oestrogen receptor positive/human epidermal growth factor receptor 2 negative BC patients in combination with exemestane in patients who have progressed to anastrozole or letrozole after the encouraging results coming from BOLERO-2 trial. Similar results were obtained by the TAMRAD investigatory study testing tamoxifen in combination with everolimus in advanced BC. This editorial focuses on the results from BOLERO-2, BOLERO 4 and BOLERO-6, which tested the clinical importance of mTOR inhibition. We comment also on the role of phosphatidylinositol 3-kinase-mTOR inhibition as reported in the BELLE-2 and BELLE-3 trials and the future directions for the inhibition of this tumour metabolic axis. 展开更多
关键词 HORMONE receptor positive/Her2-negative BREAST cancer PI3K mTOR TORC1/2 Akt EVEROLIMUS
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冠心病合并2型糖尿病患者冠状动脉正性重构的影响因素及临床预测模型构建 被引量:2
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作者 连政 于海荣 +1 位作者 刘佩林 郭彩霞 《疑难病杂志》 CAS 2024年第1期31-36,共6页
目的探讨冠心病合并2型糖尿病患者发生冠状动脉正性重构的影响因素并构建相关的临床预测模型用以早期识别高危患者,指导临床治疗。方法选择2016年1月—2023年6月于首都医科大学附属北京同仁医院心血管中心诊断的冠心病合并2型糖尿病患者... 目的探讨冠心病合并2型糖尿病患者发生冠状动脉正性重构的影响因素并构建相关的临床预测模型用以早期识别高危患者,指导临床治疗。方法选择2016年1月—2023年6月于首都医科大学附属北京同仁医院心血管中心诊断的冠心病合并2型糖尿病患者104例,通过冠状动脉内超声(IVUS)对靶病变进行测量,并计算重构指数(RI),根据RI将患者分为正性重构组和非正性重构组,搜集患者的临床资料,对2组数据进行统计并构建临床预测模型。结果Logistic回归分析结果发现,低血钙[OR(95%CI)=1.544(1.263~1.927),P<0.001]、并发急性冠状动脉综合征(ACS)[OR(95%CI)=1.198(1.024~1.401),P=0.024]、高糖化血红蛋白(HbA1c)[OR(95%CI)=1.498(1.104~2.032),P=0.010]和高低密度脂蛋白胆固醇(LDL-C)[OR(95%CI)=1.275(1.139~1.428,P<0.001]是冠心病合并2型糖尿病患者冠状动脉正性重构的独立危险因素。基于以上危险因素构建冠心病合并2型糖尿病患者冠状动脉正性重构的列线图模型,预测发生率与实际发生率基本一致,模型内部验证曲线下面积(AUC)为0.937,且具有良好的临床适用度。结论根据冠心病合并2型糖尿病患者的危险因素构建的列线图模型对其发生冠状动脉正性重构具有较好的预测效能。 展开更多
关键词 冠心病 糖尿病 2 冠状动脉正性重构 临床预测模型
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老年2型糖尿病合并社区获得性肺炎的病原学特点及死亡危险因素分析 被引量:1
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作者 许圣慧 王坤芳 +3 位作者 谢轩 于凯娜 闫丽娟 吕侯强 《临床误诊误治》 CAS 2024年第13期45-50,共6页
目的探究老年2型糖尿病合并社区获得性肺炎(CAP)病原学特点及影响死亡的危险因素。方法回顾性分析2021年4月至2023年4月收治的190例老年2型糖尿病合并CAP的病例资料,依据院内预后情况分为死亡组和存活组。比较2组感染的病原菌分布特点... 目的探究老年2型糖尿病合并社区获得性肺炎(CAP)病原学特点及影响死亡的危险因素。方法回顾性分析2021年4月至2023年4月收治的190例老年2型糖尿病合并CAP的病例资料,依据院内预后情况分为死亡组和存活组。比较2组感染的病原菌分布特点及临床资料,采用多因素Logistic回归分析老年2型糖尿病合并CAP患者死亡的相关危险因素。结果190例老年2型糖尿病合并CAP院内存活159例,占83.68%;死亡31例,占16.32%。检出病原菌包括革兰阴性菌164株、革兰阳性菌94株,真菌9株,分别占61.42%、35.21%、3.37%。检出鲍曼不动杆菌53株、肺炎克雷伯菌46株、金黄色葡萄球菌46株,肺炎链球菌32株、铜绿假单胞菌24株,分别占总病原菌的19.85%、17.23%、17.23%、11.99%、8.99%。死亡组鲍曼不动杆菌、金黄色葡萄球菌、肺炎克雷伯菌及混合菌感染率高于存活组(P<0.05)。机械通气、慢性肾脏病、肺炎严重度指数(PSI)评分≥130分、脓毒症、糖化血红蛋白(HbA1c)>8.0%、白细胞计数(WBC)>10×10^(9)/L,血乳酸、血肌酐、C反应蛋白(CRP)升高,CD4+/CD8+、CD4+降低是老年2型糖尿病合并CAP患者死亡的独立危险因素(P<0.05,P<0.01)。结论老年2型糖尿病合并CAP患者病原菌分布较广,以革兰阴性菌为主。机械通气、慢性肾脏病、PSI评分≥130分、脓毒症、HbA1c>8.0%、WBC>10×10^(9)/L,血乳酸、血肌酐、CRP升高,CD4+/CD8+、CD4+降低均为老年2型糖尿病合并CAP患者死亡的独立危险因素。 展开更多
关键词 糖尿病 2 社区获得性肺炎 老年人 革兰阴性菌 革兰阳性菌 真菌 预后 危险因素
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Positive temperature coefficient of resistivity effects of semiconducting (Bi(1/2)Na(1/2)) TiO_3-CaTiO_3-BaTiO_3 ceramics sintered in air atmosphere
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作者 马季 朱兴文 +3 位作者 张芳 徐琼 姜文中 周晓 《Journal of Shanghai University(English Edition)》 CAS 2010年第6期452-455,共4页
Y^3+-doped (Bi 1/2 Na 1/2) TiO 3-CaTiO 3-BaTiO 3 (BNCBT) positive temperature coefficient of resistivity (PTCR) ceramics sintered in air atmosphere were investigated in this study. (Bi 1/2 Na 1/2) TiO 3 (BNT... Y^3+-doped (Bi 1/2 Na 1/2) TiO 3-CaTiO 3-BaTiO 3 (BNCBT) positive temperature coefficient of resistivity (PTCR) ceramics sintered in air atmosphere were investigated in this study. (Bi 1/2 Na 1/2) TiO 3 (BNT) component can remarkably increase the onset temperature T c of PTCR ceramics with the expense of the resistivity R 25 increase. CaTiO 3 (9–27 mol%) component can decrease the resistivity, and adjust the effects of BNT phase on the T c point. For the sample containing 3 mol% CaTiO 3 , T c raises from 122 ℃ to 153 ℃ when only 0.6 mol% BNT added, while for the ones with higher CaTiO 3 content (9–27 mol%), T c is only increased by a rate of 8–9℃/1.0 mol% BNT. The effects of BNT and CaTiO 3 components on R25/Rmin (negative temperature coefficient effect) are also discussed. 展开更多
关键词 lead-free materials positive temperature coefficient of resistivity (PTCR) (Bi 1/2 Na 1/2 TiO 3 CaTiO 3 negative temperature coefficient (NTC) effect
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Graph neural network-based scheduling for multi-UAV-enabled communications in D2D networks 被引量:1
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作者 Pei Li Lingyi Wang +3 位作者 Wei Wu Fuhui Zhou Baoyun Wang Qihui Wu 《Digital Communications and Networks》 SCIE CSCD 2024年第1期45-52,共8页
In this paper,we jointly design the power control and position dispatch for Multi-Unmanned Aerial Vehicle(UAV)-enabled communication in Device-to-Device(D2D)networks.Our objective is to maximize the total transmission... In this paper,we jointly design the power control and position dispatch for Multi-Unmanned Aerial Vehicle(UAV)-enabled communication in Device-to-Device(D2D)networks.Our objective is to maximize the total transmission rate of Downlink Users(DUs).Meanwhile,the Quality of Service(QoS)of all D2D users must be satisfied.We comprehensively considered the interference among D2D communications and downlink transmissions.The original problem is strongly non-convex,which requires high computational complexity for traditional optimization methods.And to make matters worse,the results are not necessarily globally optimal.In this paper,we propose a novel Graph Neural Networks(GNN)based approach that can map the considered system into a specific graph structure and achieve the optimal solution in a low complexity manner.Particularly,we first construct a GNN-based model for the proposed network,in which the transmission links and interference links are formulated as vertexes and edges,respectively.Then,by taking the channel state information and the coordinates of ground users as the inputs,as well as the location of UAVs and the transmission power of all transmitters as outputs,we obtain the mapping from inputs to outputs through training the parameters of GNN.Simulation results verified that the way to maximize the total transmission rate of DUs can be extracted effectively via the training on samples.Moreover,it also shows that the performance of proposed GNN-based method is better than that of traditional means. 展开更多
关键词 Unmanned aerial vehicle D2 Dcommunication Graph neural network Power control position planning
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