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101.
目的:观察抗癌青黄汤联合羟基脲片治疗慢性髓系白血病(CML)慢性期毒热炽盛证的临床疗效。方法:将60例CML慢性期毒热炽盛证患者随机分为治疗组和对照组,每组各30例。对照组给予羟基脲片治疗,治疗组在对照组基础上加用抗癌青黄汤治疗。2组均以4周为1个疗程,治疗2个疗程后观察2组的综合疗效、白细胞计数、骨髓中不成熟粒细胞水平、中医证候积分以及不良反应。结果:总有效率治疗组为86.67%(26/30),高于对照组的70.00%(21/30),2组比较,差异有统计学意义(P<0.05);2组白细胞计数、骨髓中不成熟粒细胞水平、中医证候积分治疗前后组内比较及治疗后组间比较,差异均有统计学意义(P<0.05或P<0.01);不良反应发生率治疗组为13.33%(4/30),低于对照组的20.00%(6/30),组间比较,差异无统计学意义(P>0.05)。结论:抗癌青黄汤联合羟基脲片治疗CML慢性期毒热炽盛证疗效较佳,能改善患者临床症状和造血功能,值得临床推广应用。  相似文献   
102.
Ma  Yanyan  Li  Guangxue  Ye  Siyuan  Zhang  Zhiheng  Zhao  Guangming  Li  Jingyang  Zhou  Chunyan  Ding  Wenjie  Yang  Xin 《中国海洋湖沼学报》2010,28(6):1362-1370
The water and sediment discharge regulation (WSDR) project, which has been performed since 2002 before flood season every year, is of great significance to the river management in China. Until 2007, six experiments have been fulfilled to evaluate the effect of the project on the natural environment. To fill the gap of investigations, a study on flood and suspended sediment transportation and channel changing along the distributary channel of the Huanghe (Yellow) River was conducted during the WSDR project period in 2007. The lower channel was scoured rapidly and the channel became unobstructed gradually several days after the flood peak water was discharged from the Xiaolangdi Reservoir. Within four days after the flood peak at 3 000 m3/s entered the distributary, the channel in the river mouth area was eroded quickly. Both the mean values of area and depth of the main channel were tripled, and the maximum flood carrying capacity increased to 5 500 m3/s or more. Then, the river channel was silted anew in a very short time after completion of the WSDR. Favored by the WSDR project, the river status in April 2008 became better than that of the year before. The adjustment ranges of main channel parameters were about 30%, 10%, and 10% at sections C2, Q4, and Q7, respectively. The process of rapid erosion-deposition was more active 15 km away in the channel from the river mouth due to the marine influence. It is reasonable for discharging sediment at concentration peak from Xiaolangdi Reservoir at the end of the flood peak. As a result, the sediment peak reached the river mouth about two days later than that of the water current. In addition, the WSDR project has improved the development of the estuarine wetland. Wetland vegetation planted along the river banks restrained the water flow as a strainer and improved the main channel stability. It is suggested to draw water at mean rate of 150 m3/s from the Huanghe River during flood periods, because at the rate the water in the wetland would be stored and replenished in balance. Moreover, we believe that cropland on the river shoal of the lower Huanghe River should be replaced by wetland. These activities should achieve the Huanghe River management strategy of “To concentrate flow to scour sediment, stabilize the main channel, and regulate water and sediment”.  相似文献   
103.
本文选择黄河三角洲大汶流自然保护区为研究对象,以多时相遥感影像,对土地利用类型进行解译分析。同时,以平均低潮线作为分析基线,提取海岸线变化信息。结果表明:1996-2009年研究区面积净增13.35km2。各种土地利用类型中滩涂所占面积最大,养殖池所占比例最小,但增幅明显。芦苇地面积后期增长迅速,指示研究区生态环境趋向转好。自然因素(黄河来水来沙量)和人类活动(黄河调水调沙工程,湿地恢复工程,滩涂规模开发以及人类开垦造田)是研究区土地利用类型变化的直接驱动力。1976-2009年研究区海岸净造陆面积217.14km2,沙嘴变幅为29.2km。黄河入海水沙量和滨海区的海洋潮流条件共同影响着海岸线的变迁。  相似文献   
104.
基于变分模态分解算法的探地雷达信号去噪研究   总被引:1,自引:0,他引:1  
探地雷达信号属于非平稳信号,容易受到干扰噪声影响导致探测能力降低.为了消除雷达信号的噪声,经验模态分解(EMD)、总体经验模态分解(EEMD)和完全总体经验模态分解(CEEMD)等方法被应用到雷达数据处理中.EMD虽然不断被改进,但仍存在一些不足,例如容易受到噪声干扰,存在模态混叠现象,依赖经验性等问题.因此笔者采用变...  相似文献   
105.
Earth fracturing or fissuring is a natural phenomenon and a major geohazard in many countries. The factors that cause the earth to fracture were analyzed in Yuci City, in Shanxi Province of China using the geographical information system (GIS). A nonlinear simulation and assessment model of earth fracturing was established using the artificial neural network (ANN) technology to simulate the structure and function of the neural network (NN) of the human brain with engineering technology. The developed nonlinear modeling and forecasting system was used to assess and forecast the earth fracture hazard in Yuci City. The results of this study provided useful and essential information for scientific policy-making in the areas of city planning, environmental protection, and land development.  相似文献   
106.
第二代小波变换及其在地震信号去噪中的应用   总被引:12,自引:0,他引:12  
本文讨论了第二代小波变换的基本原理和变换过程,并将第二代小波变换引入到地震资料去噪处理中,基于提升法的小波变换是一种柔性的小波构造方法,它使用线性、非线性或空间变化的预测和更新算子,并能确保变换的可逆性。通过对模拟数据和实际资料的处理,证明了的它对地震信号去噪具有很好的效果。离散信号的小波去噪可分为三步:小波分解,系数缩减(切除噪声部分),信号重建。目前常用的小波去噪的方法有硬阈值法和软阈值法,这里采用软阈值法去噪。本文的提升变换采用的是Deslauriers-Dubuc(4,2)小波,基于以上变换方法,分别对含噪的模拟数据及实际地震数据进行3级可逆提升变换,对每一级上的细节信号按上述的软域值法进行处理,削减小波系数中的噪声部分,从而实现了信号去噪,结果证明去除随机噪声的效果是令人满意的。  相似文献   
107.
苏兴涛  冉灵杰  祝强  冯跃文  张永兴  张思源  孙小艳 《地质论评》2023,69(3):2023030013-2023030013
地表基质取样是开展地表基质层调查必不可少的工作环节,笔者等在浅地表层钻探技术的基础上,结合浅覆盖区矿产勘查、地球化学勘查、区域地质填图、环境调查、工程勘查、考古调查等领域钻探技术应用现状,根据不同地表景观及基质类型条件下的钻探取样需求,梳理了岩石、砾质、土质、泥质等地表基质钻探取样技术要点,研发了电动背包式钻机、Ф60/40mm单管冲击钻进、Ф50mm双管冲击钻进、Ф208mm中空螺旋钻进等取样器具及配套钻进工艺,在北京、内蒙古巴彦淖尔、浙江宁波、西藏那曲等地区开展了野外试验应用,通过获取满足要求的样品,很好的揭示了地层信息及物质组成,进一步在实践中提出了不同种类地表基质钻探取样技术方法,为建立自然资源调查监测体系及地表基质层调查工作提供钻探技术支撑。  相似文献   
108.
109.
贾峪口土洞崩塌灾害隐患点位于房山区佛子庄乡贾峪口村北侧,坡顶处存在两条近东西走向的危岩带,坡顶及坡面处植被发育较好,坡顶处未发现明显后缘裂缝,整体稳定性较好,但危岩带内大面积基岩裸露,受雨水冲刷及差异风化等作用影响,表面较为破碎,呈块状、碎裂状,岩腔、裂隙发育。通过勘查掌握了该危岩带及危岩体的基本特征,分析了其主要破坏方式及危岩的运动特征,并对其稳定性进行了定性分析与定量计算。结果表明,危岩带及危岩体在暴雨、地震等工况条件下处于不稳定状态,具有发生崩塌灾害的隐患。针对危岩带的特点,提出危岩清削+主动防护网+被动防护网的治理措施,较为有效地解除了该区域的安全隐患。  相似文献   
110.
Sediment carbon sequestration plays an essential role in mitigating atmospheric CO2 increases and the subsequently global greenhouse effect. To clarify the late Quaternary strata and carbon burial records in Yellow River delta(YRD), detailed analysis of benthic foraminifera, total carbon(TC), organic carbon(Corg), sedimentary characteristics and moisture contents of sediments, was performed on core ZK3, 30.3 m in length and obtained from YRD in 2007. Eight depositional units(designated U1-U8 in ascending order) were identified. A comprehensive analysis method of historical geography and sedimentary geology was used to determine the precise depositional ages of the modern Yellow River delta(MYRD), from which pre-MYRD ages were deduced. The results indicates that the maximum burial rates of TC, inorganic carbon(IC) and Corg occurred in the delta front(U5), and the minimum in the shallow sea(U3). Remarkable high sedimentation rates in the MYRD are responsible for burial efficiency of carbon, with an average rate of Corg burial reaching 2087±251 g(m2 yr)-1, and that of IC reaching 13741±808 g(m2 yr)-1, which are much higher than those of other regions with high contents of Corg. Therefore, YRD has a significant burial efficiency for carbon sequestration.  相似文献   
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