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101.
【摘要】 目的 探讨头颈部CT血管造影(CTA)及ABCD2评分对短暂性脑缺血发作(TIA)患者血管特征及介入治疗的意义。方法 对2010年1月—2012年1月收治的64例临床诊断TIA患者行ABCD2评分及头颈部CTA检查,分析患者头颈部血管狭窄程度、分布及其与ABCD2评分的相关性。按动脉狭窄程度将患者分为低和中高危组,中高危组中有22例患者行血管支架成形术治疗,分别于术后3、6和12个月进行随访。结果 64例患者中,头颈动脉狭窄52例(81.25%),累及动脉149段,其中颅内动脉81段(54.36%),颅外动脉68段(45.64%)。低危组患者动脉狭窄以轻、中度为主,中高危组患者以中、重度为主(χ2 = 10.126,P = 0.018)。与血管支架成形术前的 ABCD2评分(6.41 ± 0.50)分相比,术后患者3、6和12个月评分明显降低,分别为(2.88 ± 0.69)、(2.82 ± 0.63)和(3.00 ± 0.71)分,差异有统计学意义(F = 86.657,P < 0.05)。结论 头颈部CTA联合ABCD2评分能对 TIA患者狭窄血管及介入疗效进行有效评价。 相似文献
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In this study, methyl oleate was bromoacrylated in the presence of N‐bromosuccinimide and acrylic acid in one step. Homopolymers and copolymers of bromoacrylated methyl oleate (BAMO) were synthesized by free radical bulk polymerization and photopolymerization techniques. Azobisisobutyronitrile (AIBN) and 2,2‐dimethoxy‐2‐phenyl‐acetophenone were used as initiators. The new monomer BAMO was characterized by FTIR, GC‐MS, 1H, and 13C‐NMR spectroscopy. Styrene (STY), methylmethacrylate (MMA), and vinyl acetate (VA) were used for copolymerization. The polymers synthesized were characterized by FTIR, 1H‐NMR, 13C‐NMR, and differential scanning calorimetry (DSC). Molecular weight and polydispersities of the copolymers were determined by GPC analysis. Ten different feed ratios of the monomers STY and BAMO were used for the calculation of reactivity ratios. The reactivity ratios were determined by the Fineman–Ross and Kelen–Tudos methods using 1H‐NMR spectroscopic data. The reactivity ratios were found to be rsty = 0.891 (Fineman–Ross method), 0.859 (Kelen–Tudos method); rbamo = 0.671 (Fineman–Ross method), 0.524 (Kelen–Tudos method). © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 94: 2475–2488, 2004 相似文献
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Although sound AA6061-T6 joints can be produced by friction stir welding, a loss in strength takes place in the weld region. In this study, it was demonstrated that the strength of the nugget could be increased by the use of a higher strength interlayer during friction stir welding. This strength recovery cannot, however, be attainable in the heat affected zone. Although an external cooling was applied during welding in order to increase strength in the heat affected zone, it was not sufficient for achieving the required cooling condition for improved strength. 相似文献
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1 INTRODUCTIONAntimonymercaptides[1~ 4 ] usedasheatstabiliz erisattractivenotonlyforitsrelativelylowcost ,butalsoforitssimilarstabilizingeffectcomparedwiththatofthemostexcellentone organotin .Bymakingfulluseoftheplentifulantimonyresource ,developingantimonym… 相似文献
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Gürkan Kumbarolu 《Energy》2011,36(5):2419-2433
At a time of increased international concern and negotiations for greenhouse gas emission reduction, country studies on the underlying effects of greenhouse gas emission growth gain importance. The case of Turkey is particularly interesting due to rapidly growing emissions, accompanied by a political will and actions to reduce the quick growth. The refined Laspeyres method is used in this study to identify factors that accelerate or reduce the increase in Turkish CO2 emissions. A year-by-year decomposition over 1990-2007 is carried out at sectoral level based on disaggregated data that is consistent over time and consistent with international standards. Various interesting results on the underlying effects of sectoral emission growth are found. Valuable insights are gained into CO2 impacts of sectoral policies including energy and emission intensities, fuel switching and activity changes. The results yield important hints for the planning of energy and climate policy. 相似文献
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Forecasting based on sectoral energy consumption of GHGs in Turkey and mitigation policies 总被引:1,自引:0,他引:1
Recently, global warming and its effects have become one of the most important themes in the world. Under the Kyoto Protocol, the EU has agreed to an 8% reduction in its greenhouse gas (GHG) emissions by 2008–2012. The GHG emissions (total GHG, CO2, CO, SO2, NO2, E (emissions of non-methane volatile organic compounds)) covered by the Protocol are weighted by their global warming potentials (GWPs) and aggregated to give total emissions in CO2 equivalents. The main subject in this study is to obtain equations by the artificial neural network (ANN) approach to predict the GHGs of Turkey using sectoral energy consumption. The equations obtained are used to determine the future level of the GHG and to take measures to control the share of sectors in total emission. According to ANN results, the maximum mean absolute percentage error (MAPE) was found as 0.147151, 0.066716, 0.181901, 0.105146, 0.124684, and 0.158157 for GHG, SO2, NO2, CO, E, and CO2, respectively, for the training data with Levenberg–Marquardt (LM) algorithm by 8 neurons. R2 values are obtained very close to 1. Also, this study proposes mitigation policies for GHGs. 相似文献
110.