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991.
992.
文中主要介绍了用含有结晶性PE的EPDM系橡胶胶料制成橡胶部件。并使其与链烯烃系TPE(热塑性弹性体)部件直接粘接,形成橡胶,TPE复合体。在将它制成汽车门窗密封条等制品之时,装饰层TPE部分不会发生霉变发黄等变色现象。 相似文献
993.
浅粉红色—粉红色绿柱石的宝石学特征 总被引:1,自引:0,他引:1
以前珠宝市场上粉色系列绿柱石并不常见,近期发现粉色绿柱石数量增加,笔者对彩宝市场上的浅粉红色—粉红色绿柱石进行了宝石学特征研究。浅粉红色—粉红色这一系列的绿柱石与以前研究较多的祖母绿、海蓝宝石相比,颜色明显不同,在折射率、密度等方面也存在一定的差别。通过常规宝石仪器,红外光谱仪,X射线荧光能谱仪对这一系列绿柱石进行测试分析,对比发现其与常见的海蓝宝石存在一些差异;本文按照粉色绿柱石测试的折射率的结果分为A、B、C 3组,将同时检测的黄绿色绿柱石和常见的海蓝宝石分成2组,发现浅粉红色—粉红色绿柱石的折射率与密度存在正相关性,而且随着Cs元素替代的增加,Rb元素替代的减少,折射率与密度升高,粉红色绿柱石的折射率可高达1.61。 相似文献
994.
ON Savchenko FI Pro?mina NA Arutiunian VV Rakitskaia EV Sekretareva 《Canadian Metallurgical Quarterly》1996,82(4):115-122
Chemical sympathectomy of the rat uterus did not alter the main metabolic processes maintaining the uterus weight even though it changed its response to sex steroids. Sensitivity of endo- and myometrium to progesterone significantly decreased thus inducing a relative increase in the estradiol action. 相似文献
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997.
In Trypanosoma cruzi a cell surface enzyme with trans-sialidase (TS) activity has been implicated as an important factor in establishing infection. The enzyme is encoded by genes belonging to a large super-family which on the basis of sequence has been subdivided into 4 groups. TS mediates the transfer of sialic acid residues from host glycoconjugates to acceptor molecules on the parasite surface. To study the organisation of the TS genes we isolated several distinct cosmids from a library constructed with DNA from the T. cruzi X10.6 clone. In these cosmids, the TS genes (group I) were present either as single copies or as a direct tandem repeat. A common feature of the cosmids was the presence of a related group III gene located 10-12kb downstream of the TS gene(s) and arranged in the same orientation. In several of the cosmids we also identified a mucin-like glycoprotein gene located between the group I and group III genes. The mucin-like genes are part of a large polymorphic family and contour clamped homogeneous electric field electrophoresis (CHEFE) analysis showed that they were linked to members of the TS super-family at multiple sites in the X10.6 genome. Screening of a second cosmid library made with DNA from the CL-Brener clone confirmed this multiple linkage suggesting that it is a common feature of the species. This genetic organisation may have important functional significance since the mucin-like glycoproteins are the major cell surface acceptors of sialic acid. 相似文献
998.
Intervertebral discs are a common site of localized articular and some forms of systemic articular amyloid deposition. Whether there is an intrinsic matrix factor that favours amyloid deposition in intervertebral disc connective tissues is uncertain, but it is known that small localized deposits of amyloid in intervertebral discs are largely age related. As the glycosaminoglycans (GAGs) composition of the intervertebral disc is known to change with age, and as some forms of systemic amyloid deposition have been shown to be associated with particular highly sulphated GAGs, we examined the GAGs profile of amyloid deposits in intervertebral discs using mucin histochemistry (Alcian blue: MgCl2 critical electrolyte concentration) and immunohistochemistry. We found strong staining for very highly sulphated GAGs (0.9 M and 1 M MgCl2) and confirmed the presence of keratan sulphate in both localized and systemic, dialysis-associated beta 2-microglobulin amyloid deposits within disc fibrocartilage. These findings suggest that qualitative and quantitative changes in matrix GAGs, particularly strongly sulphated GAGs such as keratan sulphate, may play a role in the pathogenesis of localized and systemic amyloid deposition in intervertebral discs. 相似文献
999.
VB Matiushichev IN Sokolov AI Soldatov NA Taame 《Canadian Metallurgical Quarterly》1995,37(9-10):905-909
The influence of green-yellow light of copper laser (mean power of impulse-periodic emanation 3 W, working density of power in experiment is 200 mW/cm2) on biochemical indices of chick embryo myoblasts and neuroblasts in primary culture was studied. The content of water extracted protein was found to increase progressively, the total and specific activities of creatine kinase elevated considerably in both the cell cultures under irradiation with the total doses equal to 3 and 15 J. However, with dose of 30 J these parameters corresponded to the level characteristic of nonirradiated cultures. Mechanisms of stimulating action of highly intensive laser emanation on cell functions are discussed. 相似文献
1000.