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1.
PGRP-S (Tag7) is an innate immunity protein involved in the antimicrobial defense systems, both in insects and in mammals. We have previously shown that Tag7 specifically interacts with several proteins, including Hsp70 and the calcium binding protein S100A4 (Mts1), providing a number of novel cellular functions. Here we show that Tag7–Mts1 complex causes chemotactic migration of lymphocytes, with NK cells being a preferred target. Cells of either innate immunity (neutrophils and monocytes) or acquired immunity (CD4+ and CD8+ lymphocytes) can produce this complex, which confirms the close connection between components of the 2 branches of immune response.  相似文献   
2.
目的:探讨280例胃食管反流病(GERD)的分布特点及危险因素。方法:对临床诊断和胃镜确诊的280例GERD患者进行临床和风险因子相关性分析。结果:不论汉族还是维族,男性患者比例均明显高于女性;汉族患者高发年龄段早于维族患者(z=-2.939,P=0.003,);汉族和维族患者占反流性食管炎和Barrett食管比例分别为42.4%、81_3%及56.5%、18.8%,其中汉族患者Barrett食管比例较高(X2=14.358,P=0.000);肥胖、习惯性便秘、重体力活动者、饮食习惯不良在维族患者中的比例较高(P〈0.001)。结论:GERD与性别、年龄密切相关,男性多于女性,汉族患者发病年龄高峰旱于维族患者;汉族患者Barrett食管发生比例高于维族患者;肥胖、习惯性便秘、重体力活动、饮食习惯不良可能是GERD尤其是维族人群GERD的危险因素。  相似文献   
3.
The kinetic characteristics have been studied for noncircularly permuted variants of the human hepatitis delta virus (HDV) antigenomic ribozyme to find out the cause of the two-phase kinetics of the self-cleavage reaction. Different ways of reaction initiation, suboptimal conditions, and jumpwise changes of reaction conditions have been used, and the temperature dependences have been studied. A correlation has been shown between the apparent kinetic constant of the first reaction phase and the portion of the ribozyme molecules that self-cleaved during the first phase. Partial restoration of the initial reaction characteristics has been shown by the reinitiation of reaction being stopped after completing the first phase. On the basis of all the data obtained, a scheme of the self-cleavage reaction has been proposed including: (i) activation of the ribozyme with energy of 40-50 kcal/mol and a characteristic time of several deciminutes under optimal reaction conditions; (ii) fast and reversible reaction of the phosphodiester bond cleavage; (iii) reaction leading to isomerization of the 3',5'-phosphodiester bond to the 2',5' bond in the self-cleavage site with a characteristic activation time of tens of minutes; and (iv) practically irreversible conformational change leading to fixation of the cleavage by immobilization of the 5'-terminal nucleotide of the product in the center of the formed structure and displacement of the 3'-terminal nucleotide to the periphery. The latter process has a characteristic time of tens of minutes and a low activation energy.  相似文献   
4.
The reactivity of 100 sera taken from patients with different blood diseases and donors with respect to synthesized peptides in the variable area of protein NS4 of hepatitis C virus was studied. The presence of type-specific antibodies in the blood sera of patients with hepatitis C was shown. Two antigenic determinant corresponding to 1683-1705 and 1711-1732 amino acid residues in the protein area under study were detected. In hematological patients undergoing frequent blood transfusions mixed infection with different types of hepatitis C virus was registered; these types could be reliably determined with the use of synthetic peptides. The serotype determined with the use of peptides corresponded to the type of the circulating virus.  相似文献   
5.
目的:探讨烟龄≥15年,日吸烟量≥15支的无症状男性吸烟者的肺功能改变情况。方法:选择男性无症状吸烟者190人及非吸烟者180人,进行肺功能测定,并比较两组人群的肺功能改变情况。结果:吸烟组与非吸烟组比较,肺活量(VC)、用力肺活量(FVC)、第1秒用力呼气容积(FEV1)、Tiffeneau 1秒率(FEV1/VC)结果改变不明显,而Gaensler 1秒率(FEV1/FVC)、最大分钟通气量(MVV)、用力呼气50%肺活量的呼气流量(FEF50%)、用力呼气75%肺活量的呼气流量(FEF75%)、呼出25%~75%肺活量时的平均流量(FEF25%~75%)、肺一氧化碳弥散量(DLCO)结果均有显著降低,有统计学意义。结论:通过对无症状吸烟人群肺功能测定结果进行分析。发现有些吸烟者虽无临床症状,但已经出现了小气道及肺弥散功能的损伤,提醒吸烟者应早期戒烟,关爱自身健康,净化生存环境,提高生活质量。  相似文献   
6.
棉酚(G)及其相关物甲氧基半棉酚(DHG)、半棉酚酮(HGQ)、半棉酚(HG)、杀实夜蛾素(H1-4)等是棉花中重要的抗虫性萜烯类次生物质.利用高效液相色谱法(HPLC)对棉酚及其相关物进行了分离,测定了棉叶中的棉酚含量,讨论了不同的提取方法和测定条件对结果的影响,给出了一套简便、快速的分析测试方法,同时与紫外-可见分光光度法(苯胺法)的结果进行了对比,认为对于棉花的抗虫性的研究来说,HPLC是比较适宜的方法.  相似文献   
7.
湖南省双季稻生产系统碳效率   总被引:2,自引:0,他引:2  
提高农作物生产系统的碳效率是实现低碳农业的重要途径之一.本文采用2004—2012年农作物产量、农田作物生产系统农资投入等统计数据,利用生命周期法和投入产出法,对湖南省双季稻生产系统碳排放、碳吸收和碳效率特征及其动态进行估算.结果表明:湖南省2004—2012年双季稻生产系统年均碳排放总量为656.4×107kg CE,其中化肥和农药生产运输碳排放占农资投入碳排放总量的大部分,分别约占70.0%和15.9%,碳排放总量年际间持续降低,年均降低率为2.4%,碳排放强度则表现为增长趋势;湖南双季稻生产系统2004—2012年年均碳吸收总量为1547.0×107kg C,也呈现逐年降低的趋势,年降低率为1.2%,单位面积稻田碳吸收强度则表现为增长趋势;碳生产效率呈现缓慢增加的趋势,碳经济效率随着年份递进增加幅度较大,年均增长率为9.9%,碳生态效率则表现为稳定且较低,保持在2.4kg C·kg-1CE左右.表明湖南近几年双季稻生产系统碳综合效率提高缓慢,降低肥料和农药的投入量,提高利用效率是提高双季稻生产系统碳效率的关键.  相似文献   
8.
嫁接对梅花耐盐性的影响   总被引:2,自引:0,他引:2  
以盆栽一年生‘丰后’梅自根苗、山杏为砧木的‘丰后’梅嫁接苗以及山杏自根苗为试材,设置土壤NaCl含量分别为0(CK)、0.3%、0.6%、0.9%、1.2%和1.5%的盐胁迫处理,观测3种植物盐害情况及其叶片细胞膜透性、抗氧化酶活性、有机渗透调节物质含量的变化,并应用隶属函数值法对各盐浓度处理下3种材料叶片的生理指标进行综合评定,以明确它们的耐盐能力,为梅花向盐渍土分布较广的北方地区推广应用,以及梅花繁殖方法及梅花砧木的选择提供理论依据。结果表明:(1)随着土壤中NaCl含量的递增,‘丰后’梅自根苗、‘丰后’梅嫁接苗及山杏的盐害指数和盐害率不断增大,三者盐害指数在50%时土壤NaCl含量分别是0.545%、0.695%和0.705%,表明3种材料耐盐性由强到弱依次为山杏‘丰后’梅嫁接苗‘丰后’梅自根苗。(2)随着盐胁迫时间的延长,3种植物苗木叶片相对电导率(RC)和丙二醛(MDA)含量整体呈先上升后下降的趋势;‘丰后’梅自根苗过氧化物酶(POD)活性总体呈上升趋势,‘丰后’梅嫁接苗和山杏总体均呈现上升趋势,但个别浓度呈先上升后下降趋势;‘丰后’梅自根苗可溶性糖(SS)含量整体呈现上升趋势,‘丰后’梅嫁接苗和山杏均总体呈先下降后上升趋势,但个别较高浓度呈先上升后下降趋势。(3)隶属函数值法对盐抗性的综合评定结果为:山杏‘丰后’梅嫁接苗‘丰后’梅自根苗,综合评定结果与3种材料的盐害指数分析结果一致。研究发现,3种植物叶片所受到盐伤害的程度随NaCl胁迫浓度提高而加深,但植株叶片能对中低盐浓度处理产生一定的适应性;以耐盐性较强的山杏作为嫁接砧木后,‘丰后’梅嫁接苗比其自根苗的耐盐性增强,证明嫁接对梅花耐盐性具有一定的促进作用。  相似文献   
9.
B : LS ribozyme, a trans-variant of naturally occurring HDV ribozyme, has been constructed. The ribozyme consists of a substrate-containing LS chain and an enzyme B chain and differs from previously constructed trans-ribozymes in the length and nucleotide sequence of its oligonucleotide chains (34 and 33 bp, respectively). The chains readily associate with each other at a room temperature while the LS cleavage reaction at this temperature is negligible slow, which allowed us to investigate the association of the intact chains. At the same time the self-cleavage rate constant for the trans-ribozyme B : LS at 50 degrees C is close to those for the previously studied permuted cis-ribozymes, especially LSB variant. In addition, the dependence on the reaction conditions (Mg2+ concentration, pH, temperature) of the trans-ribozyme was similar to that of cis-ribozyme. Similar to other trans-ribozymes, B : LS ribozyme demonstrates the ability for multiple use of the enzyme B-chain with an excess of the substrate LS chain. The kinetics model of self-cleavage reaction for B : LS is presented in http://www.cardio.ru/labgen/RZ_r.html. Taken together, our results show that the original trans-variant of HDV ribozyme can be used as a model for the investigation of self-cleavage process of HDV ribozymes.  相似文献   
10.
The etiology of the outbreaks of acute pneumonia in Belgorod was established and their epidemiological features were studied. The mycoplasmal etiology of all cases of acute pneumonia in children and adults, appearing alongside acute respiratory infections resulting from the preceding outbreaks caused by influenza viruses A/Prague/, B/Leningrad/369/75, and all types of parainfluenza viruses, was shown. The droplet mechanism of the transfer of infection was established, which was confirmed by the severity of the outbreak and a high rate of infection of the medical staff at hospitals for children and adults, where patients with mycoplasma-induced pneumonia were treated.  相似文献   
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