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温度和光照强度对不同品质类型小麦旗叶光合特性和衰老的影响 被引量:83
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作者 张黎萍 荆奇 +2 位作者 戴廷波 姜东 曹卫星 《应用生态学报》 CAS CSCD 北大核心 2008年第2期311-316,共6页
以两个蛋白质含量不同的小麦品种豫麦34(高蛋白)和扬麦9号(低蛋白)为材料,研究不同温光条件对小麦灌浆期旗叶光合特性和衰老的影响.结果表明:高温、弱光处理显著降低了小麦旗叶净光合速率(Pn)及叶绿素荧光参数Fv/Fm和ΦPSⅡ,但高温和弱... 以两个蛋白质含量不同的小麦品种豫麦34(高蛋白)和扬麦9号(低蛋白)为材料,研究不同温光条件对小麦灌浆期旗叶光合特性和衰老的影响.结果表明:高温、弱光处理显著降低了小麦旗叶净光合速率(Pn)及叶绿素荧光参数Fv/Fm和ΦPSⅡ,但高温和弱光对小麦旗叶造成伤害的生理机制不同,高温主要降低了叶绿素含量(SPAD值)和Pn,灌浆后期Pn下降幅度达50%;而弱光主要降低了叶绿素荧光参数,抑制了光合系统PSⅡ的活性.高温使小麦旗叶丙二醛(MDA)含量升高,超氧化物歧化酶(SOD)活性和可溶性蛋白质含量下降,加速了植株衰老;而弱光下SOD活性较高,小麦衰老进程较高温缓慢,植株对弱光的耐受性较强.豫麦34对高温、弱光逆境的反应比扬麦9号敏感. 展开更多
关键词 小麦 高温 光照强度 叶绿素荧光 衰老
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高性能泡沫混凝土隧道隔震材料研究 被引量:52
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作者 赵武胜 陈卫忠 +1 位作者 谭贤君 黄胜 《岩土工程学报》 EI CAS CSCD 北大核心 2013年第8期1544-1552,共9页
基于泡沫混凝土作为隧道隔震材料在力学性能上的要求,开展了影响泡沫混凝土隔震性能的九因素四水平正交试验,通过正交试验得到了影响泡沫混凝土隔震性能的主要因素及各组分的最佳配合比,并研制得到了一种高性能泡沫混凝土。静力与动力... 基于泡沫混凝土作为隧道隔震材料在力学性能上的要求,开展了影响泡沫混凝土隔震性能的九因素四水平正交试验,通过正交试验得到了影响泡沫混凝土隔震性能的主要因素及各组分的最佳配合比,并研制得到了一种高性能泡沫混凝土。静力与动力试验结果表明该高性能泡沫混凝土的强度、延性、防水性能较普通泡沫混凝土都有明显改善。同时,为验证其作为隧道隔震层的减震效果,将其运用于西藏嘎隆拉隧道洞口段的抗震计算中。数值计算结果显示高性能泡沫混凝土可以有效降低隧道衬砌单元的应力及塑性破坏区的大小,从而证明其具有良好的隔震性能。综合考虑高性能泡沫混凝土的隔震性能与经济性,研究成果对高烈度区隧道的抗震设计有较好的借鉴意义。 展开更多
关键词 高性能泡沫混凝土 正交试验 高烈度 隧道 隔震层
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高强度综放开采地表沉陷规律实测研究 被引量:53
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作者 谭志祥 王宗胜 +2 位作者 李运江 孙新民 邓喀中 《采矿与安全工程学报》 EI 北大核心 2008年第1期59-62,共4页
为了为泗河堤坝加固提供实测数据,鲍店煤矿专门在堤坝下1312高强度(推进速度大、回采率高、宽深比大)综放工作面上方进行了20次地表沉陷观测.通过对观测资料的分析研究,获得了该区条件下高强度综放工作面开采时的地表移动变形规律、各... 为了为泗河堤坝加固提供实测数据,鲍店煤矿专门在堤坝下1312高强度(推进速度大、回采率高、宽深比大)综放工作面上方进行了20次地表沉陷观测.通过对观测资料的分析研究,获得了该区条件下高强度综放工作面开采时的地表移动变形规律、各种角值参数和预计参数.与普通综放面的观测成果对比发现:高强度综放面开采后地表下沉值和变形值更大;地表主要变形值更加集中、下沉盆地更陡;地表下沉过程非常剧烈,最大下沉速度高达375 mm/d. 展开更多
关键词 高强度 综采放顶煤 地表沉陷 移动变形 预计参数
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利用微米木纤维定向重组技术形成超高强度纤维板的细胞裂解理论研究 被引量:48
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作者 马岩 《林业科学》 EI CAS CSCD 北大核心 2003年第3期111-115,共5页
采用人造板微观力学和木材细胞学理论 ,提出了一种利用定向重组微米木纤维技术形成超高强度人造板的细胞裂解理论和强度参数预测方法。应用提出的理论 ,可以根据纤维、木质素、细胞直径和排列的程度 ,建立理想状态下微米重组高强度定向... 采用人造板微观力学和木材细胞学理论 ,提出了一种利用定向重组微米木纤维技术形成超高强度人造板的细胞裂解理论和强度参数预测方法。应用提出的理论 ,可以根据纤维、木质素、细胞直径和排列的程度 ,建立理想状态下微米重组高强度定向纤维板木纤维细胞在定向重组微米技术形成超高强度人造板的细胞裂解理论 ,为人造板力学运用数学手段深入到细胞结构研究的深度提供了一种新的理论和方法。 展开更多
关键词 微米木纤维 定向重组技术 强度 纤维板 人造板 微观力学 木材细胞学
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High intensity focused ultrasound in clinical tumor ablation 被引量:38
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作者 Yu-Feng Zhou 《World Journal of Clinical Oncology》 CAS 2011年第1期8-27,共20页
Recent advances in high intensity focused ultrasound(HIFU),which was developed in the 1940s as a viable thermal tissue ablation approach,have increased its popularity.In clinics,HIFU has been applied to treat a variet... Recent advances in high intensity focused ultrasound(HIFU),which was developed in the 1940s as a viable thermal tissue ablation approach,have increased its popularity.In clinics,HIFU has been applied to treat a variety of solid malignant tumors in a well-defined volume,including the pancreas,liver,prostate,breast,uterine fibroids,and soft-tissue sarcomas.In comparison to conventional tumor/cancer treatment modalities,such as open surgery,radio-and chemo-therapy,HIFU has the advantages of non-invasion,non-ionization,and fewer complications after treatment.Over 100 000 cases have been treated throughout the world with great success.The fundamental principles of HIFU ablation are coagulative thermal necrosis due to the absorption of ultrasound energy during transmission in tissue and the induced cavitation damage.This paper reviews the clinical outcomes of HIFU ablation for applicable cancers,and then summarizes the recommendations for a satisfactory HIFU treatment according to clinical experience.In addition,the current challenges in HIFU for engineers and physicians are also included.More recent horizons have broadened the application of HIFU in tumor treatment,such as HIFU-mediated drug delivery,vessel occlusion,and soft tissue erosion(“histotripsy”).In summary,HIFU is likely to play a significant role in the future oncology practice. 展开更多
关键词 high intensity FOCUSED ultrasound Thermal ablation IMAGE-GUIDED therapy Cancer BUBBLE CAVITATION BIOEFFECTS
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强流加速器中束晕-混沌的小波间隔反馈控制 被引量:23
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作者 高远 翁甲强 +1 位作者 方锦清 罗晓曙 《物理学报》 SCIE EI CAS CSCD 北大核心 2001年第8期1440-1446,共7页
在束晕 混沌的小波函数控制已实现的基础上 ,给出了一种形式更为简单的小波函数控制器 ,并研究了束晕 混沌的多周期间隔反馈控制方法 .以控制初始条件遵从Kapchinshij Vladimirskij分布的离子束为例进行模拟 ,结果表明 ,通过适当选择... 在束晕 混沌的小波函数控制已实现的基础上 ,给出了一种形式更为简单的小波函数控制器 ,并研究了束晕 混沌的多周期间隔反馈控制方法 .以控制初始条件遵从Kapchinshij Vladimirskij分布的离子束为例进行模拟 ,结果表明 ,通过适当选择间隔的周期数和小波控制器的控制参数 ,仍能很有效地对束晕 混沌进行控制 ,并能达到消除束晕及其再生现象的理想结果 . 展开更多
关键词 小波函数控制器 多周期间隔 束晕-混沌 强流离子束 强流加速器
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Petawatt class lasers worldwide 被引量:25
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作者 Colin Danson David Hillier +1 位作者 Nicholas Hopps David Neely 《High Power Laser Science and Engineering》 SCIE CAS CSCD 2015年第1期5-18,共14页
The use of ultra-high intensity laser beams to achieve extreme material states in the laboratory has become almost routine with the development of the petawatt laser. Petawatt class lasers have been constructed for sp... The use of ultra-high intensity laser beams to achieve extreme material states in the laboratory has become almost routine with the development of the petawatt laser. Petawatt class lasers have been constructed for specific research activities,including particle acceleration, inertial confinement fusion and radiation therapy, and for secondary source generation(x-rays, electrons, protons, neutrons and ions). They are also now routinely coupled, and synchronized, to other large scale facilities including megajoule scale lasers, ion and electron accelerators, x-ray sources and z-pinches. The authors of this paper have tried to compile a comprehensive overview of the current status of petawatt class lasers worldwide.The definition of ‘petawatt class' in this context is a laser that delivers >200 TW. 展开更多
关键词 DIODE PUMPED high intensity high power LASERS megajoule PETAWATT LASERS
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1330号台风海燕强烈发展和快速移动原因分析 被引量:26
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作者 张玲 许映龙 黄奕武 《气象》 CSCD 北大核心 2014年第12期1464-1480,共17页
本文运用NCEP再分析资料(水平分辨率1°×1°,垂直层次26层)和各种常规观测资料以及中央气象台台风实时定位定强数据对2013年全球最强台风海燕的特点和极端性展开分析,并运用天气学分析和动力学诊断的方法探讨"海燕&qu... 本文运用NCEP再分析资料(水平分辨率1°×1°,垂直层次26层)和各种常规观测资料以及中央气象台台风实时定位定强数据对2013年全球最强台风海燕的特点和极端性展开分析,并运用天气学分析和动力学诊断的方法探讨"海燕"强度发展的动力机制和快速移动的原因,同时发掘预报着眼点,以提高中央气象台对类似台风的综合预报能力。本文主要研究结论为:(1)"海燕"在登陆菲律宾之前的持续加强和高强度维持发生在副热带西风急流加强南压和副热带高压南侧对流层各层低纬东风同时加强的条件下。(2)副热带西风急流加强南压是导致西太平洋副热带高压加强和副热带高压南侧对流层各层低纬东风加强及"海燕"高速靠近并登陆菲律宾的重要原因。(3)"海燕"的水平风速分布存在明显不对称,呈现台风北侧东风大于南侧西风、台风东侧南风大于西侧北风的特点,其中纬向风的不对称更显著。而由台风海燕东西两侧经向风和南北两侧纬向风的不对称分布导致的切变正涡度的增加可能是台风强度持续增强的重要原因之一。(4)对流层低层水平辐合的显著加强和台风海燕南北两侧经向垂直环流圈的加强和建立也是"海燕"强度持续加强的重要原因之一。(5)台风海燕持续加强和高强度维持的主要动力机制为内核区对流层低层水平辐合和对流层中低层涡度的持续增长以及台风所处环境的高层辐散的明显增加和高低层垂直切变的减小。(6)预报启示为:对于秋冬季的台风而言,除了西太平洋副热带高压、西风槽、对流层低层偏东风、越赤道气流外,还需关注对流层上层副热带西风急流的变化,特别是对于偏西行台风而言,副热带西风急流的加强南压可能会导致台风移速的加快和强度的明显加强。另外对流层上层不光是台风的出流层,能影响台风高层出流的变化,对流层上层的环流还 展开更多
关键词 超强台风海燕 强度强 移速快 天气分析 动力学诊断分析
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高强度可食性魔芋葡甘聚糖薄膜研究 被引量:16
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作者 罗学刚 《中国包装》 2000年第1期89-91,共3页
以魔芋葡甘聚糖为原料, 添加5~10% 的增塑剂( 甘油或山梨糖醇) 、3 ~5 % 的补强剂( 海藻酸钠或明胶) , 在微量碱存在下混炼制成粘稠状溶胶流延成膜。制成的可食性魔芋葡甘聚糖薄膜具有良好的耐水性、耐热性、可分解性,... 以魔芋葡甘聚糖为原料, 添加5~10% 的增塑剂( 甘油或山梨糖醇) 、3 ~5 % 的补强剂( 海藻酸钠或明胶) , 在微量碱存在下混炼制成粘稠状溶胶流延成膜。制成的可食性魔芋葡甘聚糖薄膜具有良好的耐水性、耐热性、可分解性, 较好的拉伸强度,百分伸长率, 耐折度和透明度, 今后有望成为一种新的食品包装用膜。 展开更多
关键词 魔芋葡甘聚糖 薄膜 可食性包装膜 食品包装
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High-intensity focused ultrasound ablation:An effective bridging therapy for hepatocellular carcinoma patients 被引量:23
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作者 Tan To Cheung Sheung Tat Fan +11 位作者 See Ching Chan Kenneth SH Chok Ferdinand SK Chu Caroline R Jenkins Regina CL Lo James YY Fung Albert CY Chan William W Sharr Simon HY Tsang Wing Chiu Dai Ronnie TP Poon Chung Mau Lo 《World Journal of Gastroenterology》 SCIE CAS 2013年第20期3083-3089,共7页
AIM:To analyze whether high-intensity focused ultrasound(HIFU) ablation is an effective bridging therapy for patients with hepatocellular carcinoma(HCC).METHODS:From January 2007 to December 2010,49 consecutive HCC pa... AIM:To analyze whether high-intensity focused ultrasound(HIFU) ablation is an effective bridging therapy for patients with hepatocellular carcinoma(HCC).METHODS:From January 2007 to December 2010,49 consecutive HCC patients were listed for liver transplantation(UCSF criteria).The median waiting time for transplantation was 9.5 mo.Twenty-nine patients received transarterial chemoembolization(TACE) as a bringing therapy and 16 patients received no treatment before transplantation.Five patients received HIFU ablation as a bridging therapy.Another five patients with the same tumor staging(within the UCSF criteria) who received HIFU ablation but not on the transplant list were included for comparison.Patients were comparable in terms of Child-Pugh and model for end-stage liver disease scores,tumor size and number,and cause of cirrhosis.RESULTS:The HIFU group and TACE group showed no difference in terms of tumor size and tumor number.One patient in the HIFU group and no patient in the TACE group had gross ascites.The median hospital stay was 1 d(range,1-21 d) in the TACE group and two days(range,1-9 d) in the HIFU group(P < 0.000).No HIFU-related complication occurred.In the HIFU group,nine patients(90%) had complete response and one patient(10%) had partial response to the treatment.In the TACE group,only one patient(3%) had response to the treatment while 14 patients(48%) had stable disease and 14 patients(48%) had progressive disease(P = 0.00).Seven patients in the TACE group and no patient in the HIFU group dropped out from the transplant waiting list(P = 0.559).CONCLUSION:HIFU ablation is safe and effective in the treatment of HCC for patients with advanced cirrhosis.It may reduce the drop-out rate of liver transplant candidate. 展开更多
关键词 Ablation BRIDGING therapy CIRRHOSIS HEPATOCELLULAR CARCINOMA high-intensity FOCUSED ultrasound Liver TRANSPLANT New technology
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高强度可食性魔芋葡甘聚糖薄膜应用研究初报 被引量:19
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作者 罗学刚 《天然产物研究与开发》 CAS CSCD 2000年第4期12-16,共5页
以魔芋葡甘聚糖为原料 ,添加 5%~ 10 %的增塑剂 (甘油或山梨糖醇 )、3%~5%的补强剂 (海藻酸钠或明胶 ) ,在微量碱存在下混炼制成粘稠状溶胶流延成膜。制成的可食性魔芋葡甘聚糖薄膜具有良好的耐水性、耐热性、可分解性、较好的拉伸强... 以魔芋葡甘聚糖为原料 ,添加 5%~ 10 %的增塑剂 (甘油或山梨糖醇 )、3%~5%的补强剂 (海藻酸钠或明胶 ) ,在微量碱存在下混炼制成粘稠状溶胶流延成膜。制成的可食性魔芋葡甘聚糖薄膜具有良好的耐水性、耐热性、可分解性、较好的拉伸强度、百分伸长率、耐折度和透明度 ,今后有望成为一种新的食品包装用膜。 展开更多
关键词 魔芋葡甘聚糖 可食性包装膜 食品包装材料
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High-intensity focused ultrasound treatment for patients with unresectable pancreatic cancer 被引量:20
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作者 Peng-Zhou Li, Shai-Hong Zhu, Wei He, Li-Yong Zhu, Sheng-Ping Liu, Yan Liu, Guo-Hui Wang, Fei Ye Department of General Surgery ,Department of Radiology, Third Xiangya Hospital, Central South University, Changsha 410013, China 《Hepatobiliary & Pancreatic Diseases International》 SCIE CAS 2012年第6期655-660,共6页
BACKGROUND: High-intensity focused ultrasound (HIFU) is a non-invasive method of solid tissue ablation therapy. However, only a few studies have reported the effect of HIFU for unresectable pancreatic cancer. This stu... BACKGROUND: High-intensity focused ultrasound (HIFU) is a non-invasive method of solid tissue ablation therapy. However, only a few studies have reported the effect of HIFU for unresectable pancreatic cancer. This study aimed to evaluate the clinical benefits, survival time and complications associated with the use of HIFU ablation in patients with unresectable pancreatic cancer. METHODS: Twenty-five patients with unresectable pancreatic cancer were enrolled in our study. All patients received HIFU therapy for tumors at least once. The therapeutic effects of HIFU was evaluated in terms of Karnofsky performance status (KPS) scores, pain relief, serum CA19-9, and imaging by B-US and CT before and after the therapy. We also recorded median overall survival time and complications caused by the treatment. RESULTS: In the 25 patients, KPS scores were above 60, and increased KPS was observed in 23 patients after treatment. Pain relief occurred in 23 patients. Serum CA19-9 levels were significantly reduced one month after HIFU treatment and became negative in 5 patients. B-US revealed enhanced tumor echogenicity in 13 patients and decreased tumor blood supply in 9. Tumor necrosis was confirmed by CT in 8 patients one month after HIFU treatment. The median overall survival time was 10 months, and the 1-year survival rate was 42%. No severe complications were observed after HIFU treatment. CONCLUSION: HIFU can effectively relieve pain, increase KPS, decrease tumor growth and prolong the survival time of patients with unresectable pancreatic cancer. 展开更多
关键词 pancreatic cancer high-intensity focused ultrasound THERAPY
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新型高强度玻璃纤维制备与性能研究 被引量:20
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作者 刘建勋 朱建勋 祖群 《功能材料》 EI CAS CSCD 北大核心 2010年第7期1290-1293,共4页
研究了一种新的高强度玻璃纤维(NEWHS),其主成分为SiO2、Al2O3、MgO,总含量>96%(质量分数),其余为助熔剂、澄清剂和不可避免的杂质;经过熔制得到玻璃实验样品,对各试验样品进行高温粘度、析晶上限、新生态强度、软化点、耐酸性等性... 研究了一种新的高强度玻璃纤维(NEWHS),其主成分为SiO2、Al2O3、MgO,总含量>96%(质量分数),其余为助熔剂、澄清剂和不可避免的杂质;经过熔制得到玻璃实验样品,对各试验样品进行高温粘度、析晶上限、新生态强度、软化点、耐酸性等性能检测,得到新型高强度玻璃纤维的各性能数据:新生态强度为4600~4800MPa、软化点温度为965~970℃、耐酸性质量损失率<5.25%;新型高强度玻璃纤维的力学性能、耐温性能、耐酸性能皆高于现有高强度玻璃纤维产品(HS2、HS4),也高于AdvantexTM、Hiper-texTM玻璃纤维,接近美国S-2TM,可以投入生产。 展开更多
关键词 玻璃纤维 高强度 新生态强度 耐酸性 耐温性
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西伯利亚高压特征指数及其变率分析 被引量:19
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作者 侯亚红 杨修群 +1 位作者 李刚 王茜 《南京气象学院学报》 CSCD 北大核心 2008年第3期326-330,共5页
使用1948—2005年的NCEP/NCAR再分析月平均资料,根据海平面气压场的演变特征定义了西伯利亚高压面积、中心强度、中心经度和中心纬度4个特征指数,通过分析西伯利亚高压的特征指数,揭示了西伯利亚高压的变化特征。结果表明:1948—2005年... 使用1948—2005年的NCEP/NCAR再分析月平均资料,根据海平面气压场的演变特征定义了西伯利亚高压面积、中心强度、中心经度和中心纬度4个特征指数,通过分析西伯利亚高压的特征指数,揭示了西伯利亚高压的变化特征。结果表明:1948—2005年,西伯利亚高压具有明显的年际变化和年代际变化。在年代际尺度上,西伯利亚高压表现出随时间变化先减弱、缩小,后又振荡增强、加大的趋势。西伯利亚高压的位置变化趋势是先西撤、后东进,1999年后又西撤。另外,西伯利亚高压是随时间向南推进的。西伯利亚高压各指数异常变率存在不同的变化周期。西伯利亚高压面积和中心强度距平指数存在周期为24 a和14 a左右的年代际振荡和周期分别为8 a左右和4~6 a的年际振荡;中心经度和纬度距平指数都存在周期为准30 a及12~14 a左右的年代际振荡,同时还存在周期为8 a和3~6 a的显著年际变化。 展开更多
关键词 西伯利亚高压 异常变化 面积指数 中心强度指数 中心经度指数 中心纬度指数
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Ebselen对大强度耐力训练大鼠肝脏细胞凋亡及自由基代谢的影响 被引量:13
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作者 熊正英 刘军 《体育科学》 CSSCI 北大核心 2008年第11期62-67,共6页
目的:探讨ebselen对运动训练大鼠肝细胞凋亡表达、自由基代谢等指标的影响,为其在运动医学领域的应用提供实验依据。方法:30只SD雄性健康大鼠,随机分为3组:安静对照组(A)、运动对照组(B)和运动加药组(C),每组10只。将ebselen溶于5%的DMS... 目的:探讨ebselen对运动训练大鼠肝细胞凋亡表达、自由基代谢等指标的影响,为其在运动医学领域的应用提供实验依据。方法:30只SD雄性健康大鼠,随机分为3组:安静对照组(A)、运动对照组(B)和运动加药组(C),每组10只。将ebselen溶于5%的DMSO生理盐水溶液中,用量为50mg/kg/d,灌胃给运动加药组,其他两组灌服给同等量的DMSO生理盐水作为对照。建立为期8周的大强度耐力训练模型。常规方法检测大鼠肝脏MDA、TAOC、SOD、GSH-Px等指标,免疫组化法检测凋亡蛋白Bcl-2、Bax的表达;TUNEL检测肝细胞凋亡指数;透射电子显微镜观察肝细胞超微结构的改变。实验数据由SPSS11.0统计软件进行处理。结果:与安静组相比,运动组大鼠肝脏内MDA含量显著升高,抗氧化酶SOD、GSH-Px均下降,T-AOC下降,细胞凋亡指数AI显著增高,Bax/Bcl-2比值下降,肝细胞超微结构损伤明显;加入ebselen进行干预后,大鼠抗氧化酶SOD、GSH-Px均有所升高,MDA含量显著下降,总抗氧化能力显著升高,细胞凋亡指数AI下降,Bax/Bcl-2比值上升,肝细胞超微结构损伤被有效抑制。结论:Ebselen对运动训练导致的肝细胞损伤有明显的保护作用,机制可能与ebselen可以抑制运动诱导的肝细胞凋亡、提高大鼠肝脏抗氧化酶表达等有关。 展开更多
关键词 EBSELEN 大强度 耐力训练 自由基 肝细胞凋亡 超微结构 动物实验
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大强度间歇训练心肌细胞分子适应机制 被引量:16
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作者 马继政 牛洁 《体育科技文献通报》 2010年第3期33-34,共2页
运动强度可能是影响心脏功能的一个非常重要的运动学参数。运动诱导心肌细胞内在的分子变化机制表明大强度间歇训练可能是提高心脏功能最佳的运动方式。
关键词 大强度 间歇训练 心肌细胞 生理性适应
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现代运动减肥方法研究进展 被引量:15
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作者 杨献南 《哈尔滨体育学院学报》 2015年第3期84-90,共7页
运用文献资料法对国内外运动减肥方法的研究进行综述与讨论,提出了该研究领域未来努力的方向:(1)转变传统运动减肥观念,加强大强度间歇性运动减肥机制的系统性研究;(2)探索大强度间歇性运动对不同年龄、不同性别、不同体质水平以及不同... 运用文献资料法对国内外运动减肥方法的研究进行综述与讨论,提出了该研究领域未来努力的方向:(1)转变传统运动减肥观念,加强大强度间歇性运动减肥机制的系统性研究;(2)探索大强度间歇性运动对不同年龄、不同性别、不同体质水平以及不同疾病肥胖者产生的减肥效果;(3)重视大强度运动的强度控制和持续时间对减肥效果的影响;(4)加强研究不同有氧运动强度与持续时间对不同人群减肥效果的影响,创新测量工具与规范测量方法;(5)加强运动强度控制界线研究,明确两种运动方式的强度控制范围;(6)加强减肥与运动情境的关系以及肥胖者日常行为、生活方式改变与减肥的关系研究。 展开更多
关键词 运动减肥方法 中低强度 持续性 大强度 间歇性
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High intensity focused ultrasound: A noninvasive therapy for locally advanced pancreatic cancer 被引量:14
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作者 Feng Wu 《World Journal of Gastroenterology》 SCIE CAS 2014年第44期16480-16488,共9页
The noninvasive ablation of pancreatic cancer with high intensity focused ultrasound(HIFU) energy is received increasingly widespread interest. With rapidly temperature rise to cytotoxic levels within the focal volume... The noninvasive ablation of pancreatic cancer with high intensity focused ultrasound(HIFU) energy is received increasingly widespread interest. With rapidly temperature rise to cytotoxic levels within the focal volume of ultrasound beams, HIFU can selectively ablate a targeted lesion of the pancreas without any damage to surrounding or overlying tissues. Preliminary studies suggest that this approach is technical safe and feasible, and can be used alone or in combination with systemic chemotherapy for the treatment of patients with locally advanced pancreatic cancer. It can effectively alleviate cancer-related abdominal pain, and may confer an additional survival benefit with few significant complications. This review provides a brief overview of HIFU, describes current clinical applications, summarizes characteristics of continuous and pulsed HIFU, and discusses future applications and challenges in the treatment of pancreatic cancer. 展开更多
关键词 Pancreatic cancer high intensity focused ultrasound Focused ultrasound surgery Thermal ablation HYPERTHERMIA Therapeutic ultrasound
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Impact of a single bout of high-intensity interval exercise and short-term interval training on interleukin-6, FNDC5, and METRNL mRNA expression in human skeletal muscle 被引量:15
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作者 Malcolm Eaton Cesare Granata +3 位作者 Julianne Barry Adeel Safdar David Bishop Jonathan P.Little 《Journal of Sport and Health Science》 SCIE 2018年第2期191-196,共6页
Background: Exercise promotes numerous phenotypic adaptations in skeletal muscle that contribute to improved function and metabolic capacity. An emerging body of evidence suggests that skeletal muscle also releases a ... Background: Exercise promotes numerous phenotypic adaptations in skeletal muscle that contribute to improved function and metabolic capacity. An emerging body of evidence suggests that skeletal muscle also releases a myriad of factors during exercise, termed "myokines". The purpose of this study was to examine the effects of high-intensity interval training(HIIT) on the acute regulation of the mRNA expression of several myokines, including the prototypical myokine interleukin-6(IL-6), and recently identified myokines fibronectin type III domain-containing protein 5(FNDC5)(irisin) and meteorin-like protein(METRNL).Methods: Both before and after a 20-day period of twice-daily high-volume HIIT, 9 healthy males(20.5 ± 1.5 years performed a standardized bout of high-intensity interval exercise(HIIE; 5 × 4 min at ~80% pretraining peak power output) with skeletal muscle biopsy samples(vastus lateralis) obtained at rest, immediately following exercise, and at 3 h recovery.Results: Before training, a single bout of HIIE increased IL-6(p < 0.05) and METRNL(p < 0.05) mRNA expression measured at 3 h recovery when compared to rest. Following 20 days of HIIT, IL-6 and FNDC5 mRNA were increased at 3 h recovery from the standardized HIIE bout when compared to rest(both p < 0.05). Resting METRNL and FNDC5 mRNA expression were higher following training(p < 0.05), and there was an overall increase in FNDC5 mRNA post-training(main effect of training, p < 0.05).Conclusion: In human skeletal muscle(1) an acute bout of HIIE can induce upregulation of skeletal muscle IL-6 mRNA both before and after a period of intensified HIIT;(2) Resting and overall FNDC5 mRNA expression is increased by 20 days of HIIT; and(3) METRNL mRNA expression is responsive to both acute HIIE and short-term intense HIIT. Future studies are needed to confirm these findings at the protein and secretion level in humans. 展开更多
关键词 Brown adipose tissue Exerkines high-intensity interval training Intermittent exercise MYOKINE Obesity
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Enhancement of antitumor vaccine in ablated hepatocellular carcinoma by high-intensity focused ultrasound 被引量:12
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作者 Ying Zhang Jian Deng +1 位作者 Jun Feng Feng Wu 《World Journal of Gastroenterology》 SCIE CAS CSCD 2010年第28期3584-3591,共8页
AIM:To investigate whether tumor debris created by high-intensity focused ultrasound(HIFU)could trigger antitumor immunity in a mouse hepatocellular carcinoma model. METHODS:Twenty C57BL/6J mice bearing H22 hepatocell... AIM:To investigate whether tumor debris created by high-intensity focused ultrasound(HIFU)could trigger antitumor immunity in a mouse hepatocellular carcinoma model. METHODS:Twenty C57BL/6J mice bearing H22 hepatocellular carcinoma were used to generate antitumor vaccines.Ten mice underwent HIFU ablation,and the remaining 10 mice received a sham-HIFU procedure with no ultrasound irradiation.Sixty normal mice were randomly divided into HIFU vaccine,tumor vaccine and control groups.These mice were immunized with HIFU-generated vaccine,tumor-generated vaccine,and saline,respectively.In addition,20 mice bearing H22 tumors were successfully treated with HIFU ablation. The protective immunity of the vaccinated mice was investigated before and after a subsequent H22 tumor challenge.Using the 3-(4,5-dimethylthiazol-2-yl)-2,5- diphenyltetrazolium bromide assay,the cytotoxicity of splenic lymphocytes co-cultured with H22 cells wasdetermined in vitro before the tumor challenge,and tumor volume and survival were measured in vivo after the challenge in each group.The mechanism was also explored by loading the vaccines with bone marrowderived dendritic cells(DCs). RESULTS:Compared to the control,HIFU therapy, tumor-generated and HIFU-generated vaccines significantly increased cytolytic activity against H22 cells in the splenocytes of the vaccinated mice(P<0.001). The tumor volume was significantly smaller in the HIFU vaccine group than in the tumor vaccine group(P <0.05)and control group(P<0.01).However,there was no tumor growth after H22 rechallenge in the HIFU therapy group.Forty-eight-day survival rate was 100%in mice in the HIFU therapy group,30%in both the HIFU vaccine and tumor vaccine groups,and 20% in the control group,indicating that the HIFU-treated mice displayed significantly longer survival than the vaccinated mice in the remaining three groups(P< 0.001).After bone marrow-derived DCs were incubated with HIFU-generated and tumor-generated vaccines, the number of mature DCs expressing MHC-Ⅱ + ,CD80 + and CD86 + mo 展开更多
关键词 Hepatocellular carcinoma high-intensity focused ultrasound Immune response IMMUNOGENICITY IMMUNOTHERAPY Thermal ablation Tumor vaccine
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