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71.
目的 探讨 颅内结核常见征象及少见征象的CT表现以提高对本病的认识。材料与方法头颅CT平扫与增强扫描并随访10例患者在临床上的愈合情况。结果10例患者行抗痨治疗后好转或康复。结论CT能对颅内结核病作出准确的诊断。 相似文献
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Accurate forecasting of the intensity changes of hurricanes is an important yet challenging problem in numerical weather prediction. The rapid intensification of Hurricane Katrina(2005) before its landfall in the southern US is studied with the Advanced Research version of the WRF(Weather Research and Forecasting) model. The sensitivity of numerical simulations to two popular planetary boundary layer(PBL) schemes, the Mellor–Yamada–Janjic(MYJ) and the Yonsei University(YSU) schemes, is investigated. It is found that, compared with the YSU simulation, the simulation with the MYJ scheme produces better track and intensity evolution, better vortex structure, and more accurate landfall time and location. Large discrepancies(e.g.,over 10 hPa in simulated minimum sea level pressure) are found between the two simulations during the rapid intensification period. Further diagnosis indicates that stronger surface fluxes and vertical mixing in the PBL from the simulation with the MYJ scheme lead to enhanced air–sea interaction, which helps generate more realistic simulations of the rapid intensification process. Overall, the results from this study suggest that improved representation of surface fluxes and vertical mixing in the PBL is essential for accurate prediction of hurricane intensity changes. 相似文献
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本文对银南氧化带金矿中各种方解石的矿物学研究表明:红色方解石的热释光强度大于灰色方解石和白色方解石的热释光强度,从红色解石→灰色方解石→白色方解石,CaO CO2的总量偏离理论值的程度增大,CaO/CO2比值偏离理论值的程度也增大,亦即其晶格的缺陷增多,红外吸收强度也随之增大;包裹体研究表明,本矿床的方解石可能均系地下热卤水形成。 相似文献
75.
山谷风环流控制下的大气污染物输送和扩散过程:二维数值模拟研究 总被引:3,自引:0,他引:3
本文以兰州地区的实际地形为背景,建立了一个二维小尺度数值模式,并用它对山谷之间热力差异造成的山谷风环流及其控制下山谷中高架源排放的污染物输送和扩散过程进行了模拟研究。结果表明,在山谷风环流控制下,造成山谷内高污染浓度的主要因素有两个:一是日出前和日落后山谷风的转换;二是在白天由于山谷风环流所造成的山谷上空较强的下沉气流。 相似文献
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以陕南商洛地区为例, 选取适当的农业气候区划及垂直分层指标, 利用GIS空间分析及制图功能, 在实现指标空间化基础上, 采用模糊综合评判方法, 实现山区农业气候垂直分层。结果表明:商洛地区在不同气候带内可分别划分3个垂直气候层:北亚热带山区有温热易旱层 (低于700 m)、温暖半湿润层 (750~1250 m) 和温凉冷凉湿润层 (1250~1800 m); 暖温带山区包括温暖易旱层 (800~1100 m)、温凉半湿润层 (1100~1500 m) 和冷凉湿润层 (1500~2500 m)。并对各层适宜发展农业生态类型进行了评述。 相似文献
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在WindowsMobile手机上实现地震短信的截获,并依据短信内容,利用ArcGISMobile实现震中区相关信息的展示,可在一定程度上满足应急人员对灾情信息的了解。 相似文献
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Although Pampus minor has been classified as a new species, it still remains controversial. Was used a DNA barcoding technique based on homologous
sequence analysis of the16S and COI genes to clarify the confusion over the identification of this species. Among 12 individuals whose genetic distance was 0.002,
two haplotypes were found. According to the 16S sequences, the genetic distances ranged from 0.121 to 0.133 between P. minor and other Pampus species. Although the same the genetic distance between the two P. minor haplotypes was generated using COI sequences, the haplotype of Pm22-23, Pm28, and Pm32-33 was the same as that of Pci EF607462 and EF607466, while the haplotype
of Pm24-27 and Pm29-31 was the same as that of Pci EF607461 and EF607463-65. In addition, the genetic distance ranged only
from 0.002 to 0.005 between P. minor and Pa EF607460 and EF607458. Apart from this, the interspecies genetic distances varied from 0.135 to 0.143 between P. minor and other Pampus species according to the COI sequences. Phylogenetic trees, using combined 16S and COI data, strongly support the viewpoint that all the P. minor individuals form one clade that is in a sister position to Pampus sp. individuals (EU357803, FJ434342-FJ434343, and FJ652423-FJ652427). 相似文献