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21.
To pick up serum high risk lithogenic factors predisposing one to gallstone formation and protective factors against gallstone formation in gallbladder. We compared serum lipid and apolipoprotein level of patients with gallbladder stone (stone group) with that of patients without gallbladder stone (control group). The correlation between serum lipid, apolipoprotein level and bile lipid level, cholesterol saturated index (CSI), characteristics of lipidemia in different kinds of gallbladder stones were studied. The results showed that the increase of serum Apo A1, C2 and E level in the stone group was more significant than in the control group. But there was no statistical significance in TC, TG, LDL-C, HDL-C, Apo A2, B, C3 level between the stone and control groups. These results suggested that serum apolipoproteins perhaps are more sensitive parameters than serum lipids in distinguishing patients with stones from those without stones. There were different profiles of serum lipid and apolipoproteins in different chemical types of gallbladder stones. Increased level in serum LDL-C, Apo B and ratio of LDL-C/HDL-C were characterized by an index for cholesterol stone, otherwise that in serum TG and Apo C2 an index for pigment stones. There was a positive correlation between serum total cholesterol (TC) or Apo B, C2, C3 and cholesterol amount or CSI in gallbladder bile. Therefore, TC, Apo B, C2, C3 could be considered as high risk lithogenic factors. A positive correlation existed between serum HDL-C and lecithin in gallbladder or common bile duct (CBD) bile as well as between HDL-C and bile acids in CBD bile. Thus, HDL-C might be a protective factor against gallstone formation in gallbladder. 相似文献
22.
本文深入讨论了脉冲啁啾的非线性起源及其对干涉相关测宽(等值宽度和条纹计数)法的影响。提出根据干涉相关曲线下包络最大值位置适当降低等值宽度位置和用计算机平均处理干涉相关信息的技术以消除啁啾的影响。 相似文献
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In this note we present a proof to the conjecture given in the above paper, and therefore establish the equivalence of characterizations of fixed modes for the general case. 相似文献
26.
Sun Linzhi Luo Yi Zhang Yanan Sun Ping Qin Xinjie Gong ZhenbangPrecision Machinery Institute Shanghai University Shanghai China 《机械工程学报(英文版)》2002,15(4):303-307
An experimental bimorph piezoelectric element (PZT) actuator for small pipe robot is developed. The robot can move in φ20 mm pipe, and can carry a CCD camera for detecting cracks or fine holes on inner surface of pipe. The velocity of the robot can reach 17~22 mm/s for vertical pipe up/down, respectively. Moving principle and its performance characteristics are presented. 相似文献
27.
对原有的冶金矿山设计和生产不同能耗指标,提出统一为一个指标体系的设想,并提出了指标体系的计算公式以及各系数的选取意见。 相似文献
28.
瀑布沟水电站导流洞渐变段临时中墩的拆除,采用了微差起爆网络的控制爆破技术,取得了很好的效果。本文着重介绍控制爆破的施工方法、设计依据、设计参数以及爆破方式等。 相似文献
29.
A. Nakayama A. Kakugo J.P. Gong Y. Osada M. Takai T. Erata S. Kawano 《Advanced functional materials》2004,14(11):1124-1128
Double‐network (DN) hydrogels with high mechanical strength have been synthesized using the natural polymers bacterial cellulose (BC) and gelatin. As‐prepared BC contains 90 % water that can easily be squeezed out, with no more recovery in its swelling property. Gelatin gel is brittle and is easily broken into fragments under a modest compression. In contrast, the fracture strength and elastic modulus of a BC–gelatin DN gel under compressive stress are on the order of megapascals, which are several orders of magnitude higher than those of gelatin gel, and almost equivalent to those of articular cartilage. A similar enhancement in the mechanical strength was also observed for the combination of BC with polysaccharides, such as sodium alginate, gellan gum, and ι‐carrageenan. 相似文献
30.
Synthesis and properties of polystyrene/graphite nanocomposites 总被引:3,自引:0,他引:3
In this paper, graphite/polystyrene nanocomposite is synthesized by in situ polymerization of styrene in a tetrahydrofuran (THF) solution system of potassium (K)-THF-graphite intercalation compound (GIC). K-THF-GIC has proved to initiate polymerization of styrene by the anionic mechanism. Due to the interfacial interaction between the graphite nanolayers and the polymer, the composites exhibit higher glass transition temperature and higher thermal stability when compared to polystyrene. The percolation threshold in the conductivity of the composites is lesser than 8.2 wt% and the dielectric constant can reach as high as 136. 相似文献