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961.
AG Solov'ev GN Degteva PI Sidorov IuR Tedder NN Kononiuk LE Gromova 《Canadian Metallurgical Quarterly》1993,116(8):195-197
Comparative investigations of conventional male rat red blood with modelling of chronic alcohol-toxic influence of different types were carried out. Even a short alcohol intoxication developing against the background of ecologically unfavourable factors of the environment was shown to cause rapid development of decompensation of the blood system protective mechanisms. In these cases hematologic picture resembled that after long and hard alcohol abuse. 相似文献
962.
963.
Sialadenoma papilliferum is an extremely rare benign tumor of the esophagus. We report a 70-yr-old woman who was first thought to have adenocarcinoma in the distal esophagus. Transhiatal esophagectomy and left colon interposition were performed. The pathological diagnosis of sialadenoma papilliferum of the esophagus arising in the submucosal gland ducts was confirmed after surgery. 相似文献
964.
SM Grantham-McGregor PI Lira A Ashworth SS Morris AM Assun?ao 《Canadian Metallurgical Quarterly》1998,132(4):661-666
1. Whole cell voltage clamp electrophysiology and radioligand binding were used to examine the agonist characteristics of the two splice variants of the 5-HT3 receptor which have been cloned from neuronal cell lines. Homo-oligomeric 5-HT3 receptors were examined in HEK 293 cells stably transfected with either long (5-HT3-L) or short (5-HT3-S) receptor subunit DNAs. 2. Functional homo-oligomeric receptors were formed from both subunits, and responses to 5-HT3 receptor agonists (5-hydroxytryptamine (5-HT), 2-methyl 5-HT and m-chlorophenylbiguanide) were qualitatively similar. 3. Maximum currents (Rmax) elicited by the 5-HT3 receptor agonists m-chlorophenylbiguanide (mCPBG) and 2-methyl-5-HT (2-Me-5-HT), as compared to 5-HT, differed in the two splice variants: Rmax mCPBG/Rmax 5-HT values were 0.68+/-0.04 and 0.91+/-0.01 in 5-HT3-L and 5-HT3-S receptors, respectively. Comparable values for 2-Me-5-HT were 0.30+/-0.02 and 0.23+/-0.02. 4. Radioligand binding data showed no difference in affinity of agonist or antagonist binding sites; thus the six amino acid deletion appears to cause differences in agonist efficacy. 5. The role of the 6 amino acid insertion was further investigated by use of site-directed mutagenesis to create two mutant receptors, one where serine 286 was replaced with alanine, and the second where all 6 amino acids were replaced with alanines. 6. Examination of the mutant receptors when stably expressed in HEK 293 cells revealed agonist properties resembling long and not short 5-HT3 receptors. Thus specific amino acids in this region are not responsible for the observed differences. 7. The data show intracellular structure can have significant effects on ligand-gated ion channel function, and suggest that minor changes in structure may be responsible for differences in function observed when ligand-gated ion channel proteins are modulated intracellularly. 相似文献
965.
微机技术已广泛应用于工业自动控制领域中。随着软件开发平台的不断推出 ,软件系统设计在工业自动控制中占据越来越重要的位置。文章在总结开发工业自动控制软件系统经验教训的基础上 ,提出了一套切实可行的软件设计思想和方法。使用这种方法设计的软件具有美观的用户界面、可靠的软件性能以及合理的资源使用等优点。文章着重说明了微机显示及接口软件的标准功能和设计方法 相似文献
966.
Airborne house dust elicits a local lymph node reaction and has an adjuvant effect on specific IgE production in the mouse 总被引:1,自引:0,他引:1
Indoor suspended particulate matter (SPM) consists of many different types of particles, the vast majority of which are less than 2.5 microm in diameter. An important question is how these particles, being inhalable, contribute to asthma and respiratory symptoms. One possibility is that these particles have an adjuvant effect on the immune response and increase the IgE production, or cause a non-specific irritation in the airways, contributing to bronchial hyper-responsiveness. In this study, the adjuvant activity of indoor SPM on the response to the model allergen ovalbumin (OA) in BALB/c mice was investigated, using the popliteal lymph node (PLN) assay. The adjuvant activity on the local lymph node response was determined by measuring the PLN weight, cell numbers and cell proliferation, and the adjuvant activity on the IgE production by measuring the levels of serum IgE specific to OA. SPM was found to give a significant PLN response, both when injected alone and together with OA. SPM was also found to enhance the production of specific IgE to OA when injected together with OA, after reinjection with OA, compared with immunisation with OA alone. 相似文献
967.
968.
针对一种线性调频连续波(LFMCW)雷达系统结构,提出一种中频接收机硬件平台的设计方案。该方案采用AD8347正交解调器做I/Q下变频,AD9248模数转换器做采样,EP3C80 FPGA做数字信号处理,PCI9054做PCI接口,并给出了系统软件的设计方法。实现了对线性调频连续波雷达中频信号的接收、处理和存储。通过测试,该接收机能够准确测量出目标信号的频率信息,可为雷达成像提供原始数据。 相似文献
969.
970.
通过可控自组装途径,开发一种基于4-巯基苯硼酸(4-mercaptoboric acid,4-MPBA)探针的表面增强拉曼散射(surface-enhanced Raman scattering,SERS)芯片的超灵敏亚硫酸根离子(SO32-)定量技术。该技术借助SO32-到SO42-的氧化转化特性,利用Lewis酸碱配位原理,建立基于特征峰1 382 cm-1与1 070 cm-1的比率型定量检测方程。该比率定量策略排除了SERS基底不均匀导致的检测误差,有效提高检测信号获取的可靠性,检出限低至5×10-8 mol/L,并在5×10-8~1×10-3 mol/L的浓度范围内呈良好线性关系(R2=0.997 4)。检测到白糖中SO32-含量为1.42 mg/kg,加标回收率在98.38%~107.82%之间,说明该方法对于实际样品中SO32-的痕量检测具有极大优势。 相似文献