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91.
利用二氧化硅特异地吸附核素的特性,建立了从琼脂糖凝胶中回收DNA的方法。结果表明本方法对1300 ̄3500bp的DNA回收效果较好,回收效率达60% ̄70%,100 ̄1500bp,3500 ̄5000bp的DNA亦能被有效地回收。通过对回收DNA的酶切,连接等实验,证实了所回收的DNA片段能够满足进一步的实验要求。该方法简单,快捷,经济,适用,值得推广。 相似文献
92.
淋巴因子激活的NK细胞杀伤肿瘤细胞的免疫电镜观察 总被引:3,自引:0,他引:3
用胶体金标记的扫描与透射免疫电镜术观察CD16^+淋巴因子激活的杀伤细胞杀伤肺腺癌细胞系LTEPa2或人红白血病细胞K562的过程。发现CD16^+LAK细胞能伸出分支的指状突起较深地插入肿瘤细胞浆内,造成靶细胞表面大小深浅不等的隐窝,及陷窝内局部细胞膜损伤,在CD16^+LAK细胞这种指状突起基底部附近的浆内,有大量胞浆颗粒与囊泡聚集。靶细胞被攻击后常发生凋落型死亡。同时可见坏死型死亡。说明CD 相似文献
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We report here the preliminary effects of zinc iontophoresis in treatment of 26 Rp patients who had decreased zinc serum level or abnormal ratio of serum copper to zinc. Through more than 20 to 30 times of therapy, the vision of 15.38% eyes increased more than "3 lines", 4% eyes increased more than 5 degrees in the visual field, 13.46% eyes improved in dark adaptation threshold (greater than 1.0), the visual functions of the rest eyes were slightly improved or unimproved. The fundus didn't change before & after treatment. There were no changes of ERG in 8 eyes of 4 cases. In addition, the advantages and disadvantages between Zn iontophoresis and Zn compound taken orally, the improvement of vision by direct electric current therapy, the relationship between the metabolism of Zn element and Vit A and influence of Zn over the mechanism of dark adaptation were also briefly discussed. 相似文献
95.
石蜡切片中BCL-6抗原失活机制及修复 总被引:1,自引:1,他引:0
目的 探讨石蜡切片中BCL 6抗原失活机制及修复的最佳方法 .方法 淋巴组织反应性增生 11例石蜡切片分别用二乙胺四乙酸 (EDTA)、柠檬酸、碳酸钠及去离子水 4种与钙离子结合力不同的修复液 ,结合高压、微波和煮沸 3种不同方法修复后 ,比较检出的BCL 6阳性率及强度 .结果 BCL 6阳性率由高至低依次为 :EDTA 0 .73>柠檬酸 0 .45 (P<0 .0 1) >碳酸钠 0 .12 (P <0 .0 1) ,去离子水组无 1例阳性 .高压修复阳性率 0 .5 5 >微波修复 0 .2 8和煮沸修复 0 .12 (P <0 .0 5 ) .不同修复液与高压结合修复检出BCL 6阳性率及强度 :EDTA与柠檬酸阳性率分别为 1,0 .82 (P >0 .0 5 ) ,高于碳酸钠组 (0 .36 )和去离子水组 (0 ) (P <0 .0 1) .EDTA组强阳性占 0 .82 ,显著高于其他各组 (P <0 .0 1) .结论 EDTA结合高压是修复BCL 6抗原的理想方法 ,钙离子的参与可能是甲醛固定后BCL 6抗原失活的原因之一 相似文献
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97.
Yi-Fei Zhang Jing-Jing Guo Fan Yang Hang-Yu Zhou Na-Na Zhang Xiao-Chuan Xiong Yue Feng Yong-Qiang Deng Cheng-Feng Qin 《Journal of medical virology》2023,95(1):e28290
The geographic range of Zika virus (ZIKV) has expanded from Asia to the Americas, leading to the 2015–2016 pandemic with enhanced neurovirulence. At present, ZIKV is continuously circulating in many Southeast Asian countries. Unfortunately, the persistent evolution of ZIKV in Southeast Asia and its influence on the biological characteristics of the virus remain incompletely understood. In this study, the in vitro and in vivo properties of a new ZIKV isolate obtained from Cambodia in 2019 (CAM/2019) were characterized and compared with those of the Cambodian strain (CAM/2010). Compared with CAM/2010, the CAM/2019 virus showed similar plaque morphology and growth curves in cell cultures and induced comparable viremia and organ viral loads profiles in both BALB/c and A129 (IFNAR1−/−) mice upon intraperitoneal (i.p.) inoculation. Remarkably, the CAM/2019 virus exhibited enhanced neurovirulence in neonatal mice compared with CAM/2010, with a 74-fold reduction in the 50% lethal dose (LD50). Consistently, CAM/2019 produced higher viral loads in the brains of BALB/c neonatal mice than CAM/2010 did. Sequence alignment showed that the CAM/2019 virus has acquired 12 amino acid substitutions, several of which were found to be associated with neurovirulence. In particular, the CAM/2019 virus shared an A1204T substitution in NS2A with the Thai isolate SI-BKK02 that was isolated from a microcephaly case. Taken together, our results indicate that a ZIKV strain isolated with specific mutations has emerged in Cambodia, highlighting the need for extensive molecular and disease surveillance in Cambodia and other Asian countries. 相似文献
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100.
Xin Sun Yunfeng Guo Shengdu Yang Kai Wang Lan Xie Bai Xue 《Macromolecular chemistry and physics.》2023,224(15):2300072
The poly(l -lactic acid) (PLLA)/carbon nanomaterials composite foams with hierarchical surface microstructural and internal conductive pathways are successfully prepared by a simple crystallization-assisted rapid phase separation (CARPS). The dimension and morphology of carbon nanomaterials can induce different crystallization forms to construct the hierarchical surface microstructure, and they are distributed on the phase interface of solvent and non-solvent to form conductive pathways. It is found that the heterogeneous nucleation of nanomaterials promotes a significant increase in crystallinity, and a stacked granular structure formed on the surface promotes the increase of the water contact angle to 148.7°. Foams with interconnecting pore structures contribute to the formation of 85.3% porosity and 12.33 g g−1 oil absorption. Carbon nanomaterials are distributed on the pore walls of the porous foam, which converts the foam from an insulating material to a conducting polymer. Furthermore, the uniform distribution of nanomaterials significantly affects the thermal stability of the PLLA. In belief, the multifunctional biodegradable foam, prepared by a CARPS method, makes it promising for industrial production and has potential applications in electrical conductivity, oil-water separation, and many other fields. 相似文献