东南亚金融危机的成因及启示

日墨金融危机,特别是今年东南亚金融危机的爆发并不是偶然的,国际投机资本只是助长了危机的程度,危机的真正原因在于内部经济结构严重失衡

国际游资的进入与管理

国际游资的进入与管理张建忠1996年底人民币实现了经常项目下可自由兑换，这为国际游资进入中国提供了一定的便利条件。墨西哥金融危机充分表明了国际游资的危害性，为此中国必须借鉴有关国家的经验，尽可能减少游资的负面影响。本文将主要分析国际游资进入我国的渠道..

后危机时代福建外经贸的转型与发展

在由美国次贷危机所引发的全球金融危机中,福建省的对外经济贸易经受了严峻的考验,同时也暴露出一些不足。因此,在后危机时期,重新审视福建外贸发展的现状与存在的问题,分析后危机时期福建外经贸发展的新形势,探讨后危机时期福建外贸发展的思路与对策,不仅很有必要,而且意义重大

Field map-based rectification of susceptibility distortion and signal compensation in diffusion tensor imaging

目的采用基于体素的场图对磁共振弥散张量成像(diffusion-tensor; imaging,DTI)进行几何变形矫正及信号补偿研究,扩大DTI临床研究及应用价值。材料与方法获取29名健康人脑场图,分别对其DTI进行相位反; 卷积计算及信号校准补偿,将结果配准到3D结构图像。选择对磁场敏感的双侧颅底额叶和颞叶作为观察脑区,对磁场不敏感的丘脑作为对照脑区,对部分各向异性; (fractional; anisotropy,FA)值及信号的差异及其与结构像的形态差异进行统计分析。结果在颅底额叶和颞叶,DTI的磁敏感变形得到了矫正,因场不均性导致; 的信号损失得到了补偿。结论高场中DTI的畸变及体素信号丢失可应用场图的校准得到明显矫正,有利于进一步扩大高场DTI在临床中的应用价值。Objective: This study was designed to employ the voxel-based field map; to rectify the geometric deformation and compensate the signal loss of; diffusion tensor imaging (DTI), and thus facilitate the studies and; clinical applications of DTI. Materials and Methods: Brain field maps; from 29 healthy persons were first used to get B1 field heterogeneous; signals, and then the compensation and phase disconsolation of signals; were performed. Finally, the geometry deformations of DTI were rectified; and registered to 3D images. Magnetic sensitive bilateral temporal lobes; and frontal lobes were selected as regions of interesting and meanwhile,; magnetic insensitive thalamus was selected as control area. Results:; Geometry deformations of DTI produced by different susceptibilities; between specific tissues were completely rectified, and thus the signal; loss was compensated and the accuracy of DTI was significantly enhanced.; Conclusion: Signal compensations and deformation rectifications can be; well achieved using field map, which may improve the applications of DTI; in neurosurgery.国家自然科学基金面上项

A New Comparison Principle for Impulsive Functional Differential Equations

通过归纳总结建立了一种关于具有有限时滞的脉冲泛函微分方程的新的比较原理,并利用这种比较原理,得到了几个时滞脉冲微分方程稳定性的充分条件。最后举出了一个例子来说明研究结果的有效性。In this paper,we establish a new comparison principle for impulsive differential systems with time delay,then,using this comparison principle,we obtain some sufficient conditions for several stabilities of impulsive delay differential equations.Finally,we present an example to show the effectiveness of our results

食管癌患者血清可溶性肿瘤坏死因子受体水平测定

背景:目前尚无敏感性和特异性较高的血清肿瘤标志物用于临床诊断食管癌。目的:通过测定食管癌患者血清可溶性肿瘤坏死因子受体(sTNFR)水平的变化,探讨其在食管癌诊断和监控中的临床意义。方法:应用双抗体夹心酶联免疫吸附测定(ABC鄄ELISA)检测56例食管癌患者和10名健康成人的血清sTNFR鄄Ⅰ、sTNFR鄄Ⅱ水平,并与血清癌胚抗原(CEA)水平进行比较。结果:食管癌患者的血清sTNFR鄄Ⅰ和CEA水平显著高于健康对照组(P<0.001),而sTNFR鄄Ⅱ水平则显著低于健康对照组(P<0.001);sTNFR鄄Ⅰ与CEA的阳性率无显著差异,但均显著低于sTNFR鄄Ⅱ(P<0.001)。食管癌切除术后,患者的血清sTNFR鄄Ⅰ、sTNFR鄄Ⅱ水平均呈升高趋势,而CEA水平则无明显变化。结论:同时检测血清sTNFR鄄Ⅰ、sTNFR鄄Ⅱ水平有助于诊断食管癌和评估机体的免疫状态

KOH活化法制备煤基活性炭

新疆煤炭资源丰富,约占全国总储量的40%。活性炭是一种优良的吸附剂,原料来源广泛,其中以新疆煤炭为原料制备高性能的煤基活性炭可以增加煤炭的高效利用,提高其经济价值。但由于煤炭的灰分含量普遍较高且组成复杂,以物理活化法制得的煤基活性炭性能较低,因此本文采用kOH为活化剂,研究碱碳比、终温和升温速率对活性炭比表面积和孔结构的影响,最终确定煤基活性炭的最佳制备工艺条件为:碱碳比2:1、活化终温800℃、升温速率5℃/MIn,在此实验条件下制得比表面积为1560 M2g-1,孔容为0.622CM3g-1的煤基活性炭