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71.
Huang Y Tang C Wang S Lu Y Shen W Yang J Chen J Lin R Cui S Xiao H Qu S Lai X Shan B 《BMC neuroscience》2012,13(1):75
ABSTRACT: BACKGROUND: Acupuncture has been applied to aid in the recovery of post-stroke patients, but its mechanism is unclear. This study aims to analyze the relationship between acupuncture and glucose metabolism in cerebral functional regions in post-stroke patients using 18 FDG PETCT techniques. Forty-three ischemic stroke patients were randomly divided into 5 groups: the Waiguan (TE5) needling group, the TE5 sham needling group, the sham point needling group, the sham point sham needling group and the non-needling group. Cerebral functional images of all patients were then acquired using PET-CT scans and processed by SPM2 software. RESULTS: Compared with the non-needling group, sham needling at TE5 and needling/sham needling at the sham point did not activate cerebral areas. However, needling at TE5 resulted in the activation of Brodmann Area (BA) 30. Needling/sham needling at TE5 and needling at the sham point did not deactivate any cerebral areas, whereas sham needling at the sham point led to deactivation in BA6. Compared with sham needling at TE5, needling at TE5 activated BA13, 19 and 47 and did not deactivate any areas. Compared with needling at the sham point, needling at TE5 had no associated activation but a deactivating effect on BA9. CONCLUSION: Needling at TE5 had a regulating effect on cerebral functional areas shown by PET-CT, and this may relate to its impact on the recovery of post-stroke patients. 相似文献
72.
对不同新旧程度的特定红外辐射材料的红外光谱分析,找到了变化显著的红外特征峰为1122cm~(-1),并以此峰峰面积S的函数表征该材料有效性的参考指标Ⅰ。 相似文献
73.
Rosenthal EC Cui H Koch J Escarpa Gaede P Hummert M Dechert S 《Dalton transactions (Cambridge, England : 2003)》2005,(18):3108-3117
A series of mixed alkoxyalkoxo chloro complexes of vanadium(V), [VOCl2(OCH2CH2OR)]2 (R = Me, Et, iPr, Bz), [VOCl2(OCMe2CH2OMe)]2 and [VOCl2(OCH2(cyclo-C4H7O)]2, were synthesised and characterised. The title compounds can be obtained either from VOCl3 and the alkoxyalcohols by HCl elimination or from the corresponding lithium alkoxides and VOCl3 by salt metathesis reaction. X-Ray diffraction studies revealed the title compounds to be dimers with chloride bridging ligands and intramolecular ether coordination. Electrochemical results obtained by cyclic voltammetry indicate irreversible, reductive behaviour. The interactions of the title compounds with oxygen, nitrogen and phosphorus donor ligands were examined. Phosphorus and nitrogen donors lead to reduction products whereas tetrahydrofuran coordinates to the vanadium(V) centre by breaking the chloride bridge. All tetrahydrofuran complexes, [VOCl2(OCH2CH2OR)(thf)] (R = Me, Et, iPr) and [VOCl2(OCMe2CH2OMe)(thf)], have been characterised by single-crystal X-ray diffraction. The solid-state structures of these complexes show that they consist of six-coordinate monomers. Reaction of [VOCl2(OCH2CH(2)OMe)]2 with Me3SiCH2MgCl gave [VO(CH2SiMe3)3], which has been structurally characterised. The compounds were tested as catalysts for epoxidation and polymerisation reactions. They convert unfunctionalised olefins into the corresponding epoxides with moderate activity. They are good pre-catalysts for the polymerisation of ethene and oligomerise 1-hexene. 相似文献
74.
对一种新型的超导低温系统电流引线(Peltier引线)进行了分析;建立了考虑热界面效应的数学模型,给出了可用于迭代求解的解析表达式;以最小漏热和最小功耗两种目标分别对直接冷却下的Peltier引线进行了结构优化,分析了热电材料与铜之间的接触界面热阻、电阻的影响。不考虑界面阻力时,优化得到的PCL引线与二元电流引线相比,漏热可减少近30%,功耗可减少约26%。界面阻力会明显削弱PCL引线的优势,需在设计中给与足够重视,依据工作电流将界面阻力控制在可以接受的范围。 相似文献
75.
Mohasan Muhammad Aqeel Anas Bin Lv Pengyu Yang Yantao Duan Huiling 《Acta Mechanica Sinica》2021,37(3):447-455
Acta Mechanica Sinica - In this work, we numerically study the impact of a water droplet onto a deep oil pool. Two fluids are immiscible and the viscosity of the pool liquid is changed... 相似文献
76.
Yi-en Du Xianjun Niu Xinru He Kai Hou Huiling Liu Caifeng Zhang 《Molecules (Basel, Switzerland)》2021,26(19)
In this work, TiO2/CdS nanocomposites with co-exposed {101}/[111]-facets (NH4F-TiO2/CdS), {101}/{010} facets (FMA-TiO2/CdS), and {101}/{010}/[111]-facets (HF-TiO2/CdS and Urea-TiO2/CdS) were successfully synthesized through a one-pot solvothermal method by using [Ti4O9]2− colloidal solution containing CdS crystals as the precursor. The crystal structure, morphology, specific surface area, pore size distribution, separation, and recombination of photogenerated electrons/holes of the TiO2/CdS nanocomposites were characterized. The photocatalytic activity and cycling performance of the TiO2/CdS nanocomposites were also investigated. The results showed that as-prepared FMA-TiO2/CdS with co-exposed {101}/{010} facets exhibited the highest photocatalytic activity in the process of photocatalytic degradation of methyl orange (MO), and its degradation efficiency was 88.4%. The rate constants of FMA-TiO2/CdS was 0.0167 min−1, which was 55.7, 4.0, 3.7, 3.5, 3.3, and 1.9 times of No catalyst, CdS, HF-TiO2/CdS, NH4F-TiO2/CdS, CM-TiO2, Urea-TiO2/CdS, respectively. The highest photocatalytic activity of FMA-TiO2/CdS could be attributed to the synergistic effects of the largest surface energy, co-exposed {101}/{010} facets, the lowest photoluminescence intensity, lower charge-transfer resistance, and a higher charge-transfer efficiency. 相似文献
77.
78.
用甲基氯硅烷蒸气或溶液处理硅胶,均可制成憎水硅胶。关于憎水硅胶的吸附性能和热稳定性的研究,文献中时有报道。本文主要探讨以下3个问题:(1)在水蒸气吸附中,硅胶表面自由羟基和缔合羟基究竟哪种起主要作用;(2)从吸附水蒸气等数据讨论硅胶表面有机基团—OSi(CH_3)_3的热稳定性;(3)用二甲基二氯硅烷(DMCS)和三甲基氯硅烷(TMCS)处理的憎水硅胶,哪种硅胶的热稳定性较高。这些基本问题,不仅具有学术意义,对研究氧化物表面改性也有参考价值。 相似文献
79.
本文就表面活性剂-磺基水杨酸对镱在乙炔-空气火焰中的高增敏作用进行了研究,结果表明,在十二烷基硫酸钠(SDS)与磺基水杨酸(SSA)共存时。镱的灵敏度增高50倍,其它稀土元素和一些阴离子对Yb的干扰得到了有效的抑制,对硫酸根和磷酸根尤其明显,同时也研究了该体系的增敏机理。在Yb-SDS-SSA体系中,镱的检出限为0.031μg/mL,在0.050~2.0μg/mL镱的浓度范围内,其相对标准偏差为3.0%。 相似文献
80.