目的了解肺表面活性蛋白D(surfactant protein D,SP-D)基因rs721917位点T/C多态性分布情况,并探讨其与深圳地区儿童过敏性鼻炎(allergic rhinitis,AR)遗传易感相关性。方法收集2016年3月~2018年8月来医院就诊并确诊为AR患儿165例为实验...目的了解肺表面活性蛋白D(surfactant protein D,SP-D)基因rs721917位点T/C多态性分布情况,并探讨其与深圳地区儿童过敏性鼻炎(allergic rhinitis,AR)遗传易感相关性。方法收集2016年3月~2018年8月来医院就诊并确诊为AR患儿165例为实验组,选择同期体检的健康儿童120名为对照组,采用PCR限制性片段长度多态性(PCRRELP)法检测两组SP-D基因rs721917位点T/C多态性,同时采用酶联免疫吸附(ELISA)法检测血清中总IgE水平,并对检验结果进行统计分析。结果实验组和对照组SP-D基因rs721917位点多态性均检出TT,TC和CC 3种基因型,经Hardy-Weiberg检验,均符合Hardy-Weinberg平衡定律(χ^2=0.6218,P>0.05),具有样本代表性;实验组患者血清中总IgE(1oge)水平为5.36±0.92,明显高于对照组的2.17±0.34,差异有统计学意义(t=3.9262,P<0.05);实验组患者SP-D基因rs721917位点CC基因型及C等位基因频率分别为29.70%和51.82%,明显高于对照组的11.67%和32.08%,差异均有统计学意义(χ^2=2.8703~3.1546,P<0.05);不同性别AR患者SP-D基因rs721917位点TT,TC,CC基因型及T,C等位基因频率之间差异均无统计学意义(χ^2=0.3251~1.0624,P>0.05);TT,TC及CC基因型AR患者血清中总IgE(1og_e)分别为5.01±0.85,5.27±0.90及5.54±1.02,各基因型AR患者血清中总IgE水平之间差异均无统计学意义(t=0.3802~0.5615,P>0.05)。结论 AR患者血清中总IgE水平明显高于健康人群,但SP-D基因rs721917位点不同基因型AR患者间无差异,同时SP-D基因rs721917位点CC基因型及C等位基因可能是深圳地区AR发病的危险遗传易感基因之一。展开更多
Vulcanized latex has superior filmforming behaviour and film properties, which constitute the most important reason for its wide industrial use. It is well known that ordinarily rubber lacks tackness after it has been...Vulcanized latex has superior filmforming behaviour and film properties, which constitute the most important reason for its wide industrial use. It is well known that ordinarily rubber lacks tackness after it has been vulcanized, but when rubber is vulcanized in the latex form, the latex particles are effectively held together to form film with excellent properties. There have been many explanations for this unusual phenomenon, among which, Humphreys’ interpretation is one that is most widely accepted.展开更多
Since the discovery of the vulcanization of latex by Schidrowitz, vulcanized latex has been in wide commercial use for almost half a century. Owing to its peculiar form, the vulcanization of latex has a number of uniq...Since the discovery of the vulcanization of latex by Schidrowitz, vulcanized latex has been in wide commercial use for almost half a century. Owing to its peculiar form, the vulcanization of latex has a number of unique features in contrast to that of crude rubber. Concerning the vulcanization process of latex, a unified realization is still lacking and little work has been carried out. This note gives, in addition to our preliminary view on this subject, an account of our recent work based on the results obtained in experiments and practice.展开更多
文摘Vulcanized latex has superior filmforming behaviour and film properties, which constitute the most important reason for its wide industrial use. It is well known that ordinarily rubber lacks tackness after it has been vulcanized, but when rubber is vulcanized in the latex form, the latex particles are effectively held together to form film with excellent properties. There have been many explanations for this unusual phenomenon, among which, Humphreys’ interpretation is one that is most widely accepted.
文摘Since the discovery of the vulcanization of latex by Schidrowitz, vulcanized latex has been in wide commercial use for almost half a century. Owing to its peculiar form, the vulcanization of latex has a number of unique features in contrast to that of crude rubber. Concerning the vulcanization process of latex, a unified realization is still lacking and little work has been carried out. This note gives, in addition to our preliminary view on this subject, an account of our recent work based on the results obtained in experiments and practice.
