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101.
Astaxanthin (AST) is a product made from marine organisms that has been used as an anti-cancer supplement. It reduces pontin expression and induces apoptosis in SKBR3, a breast cancer cell line. Using Western blotting and qRT-PCR analyses, this study revealed that in the T47D and BT20 breast cancer cell lines, AST inhibits expression of pontin and mutp53, as well as the Oct4 and Nanog cancer stem cell (CSC) stemness genes. In addition, we explored the mechanism by which AST eradicates breast cancer cells using pontin siRNAs. Pontin knockdown by pontin siRNA reduced proliferation, Oct4 and Nanog expression, colony and spheroid formation, and migration and invasion abilities in breast cancer cells. In addition, reductions in Oct4, Nanog, and mutp53 expression following rottlerin treatment confirmed the role of pontin in these cells. Therefore, pontin may play a central role in the regulation of CSC properties and in cell proliferation following AST treatment. Taken together, these findings demonstrate that AST can repress CSC stemness genes in breast cancer cells, which implies that AST therapy could be used to improve the efficacy of other anti-cancer therapies against breast cancer cells.  相似文献   
102.
[目的]研究不同诱变剂量对棉花遗传变异的影响.[方法]利用100~300Gy的60Co-γ射线对5个陆地棉材料干种子进行辐射处理,对其M3、M4农艺经济性状的遗传变异进行分析.[结果]5个品种(系)在200Gy诱变剂量达到半致死剂量,200~300Gy是陆地棉理想的诱变剂量.M4群体的单铃重、单株铃数、株高和果枝数平均变异系数均超过10;以上,250Gy剂量诱变的辐射诱变后代M4群体表型性状变异系数存在明显差异.[结论]200~300Gy辐射剂量对不同棉花品种的诱变效果存在差异,揭示了辐射创造丰富的遗传变异.  相似文献   
103.
The production of miniature animals has been suggested for use in organ transplantation. At present, many of the studies about application of animal organs to human have been focused on pigs because of the number of advantages involved and due to their similarities with human. However, a physiological analysis of the organs to be transplanted has not yet been carried out. Therefore, this study analyzed whether or not there were physiological and morphological differences in the hearts of conventionally-reared pigs and micropigs. In this study, the morphological and physiological functions of the heart were examined using radiographic and echocardiographic equipment. In the lateral radiographic view, the heart of the micropig has a larger cardiac long axis : short axis ratio than does the conventional pig, but the difference in the vertebral heart score was not significant. In addition, there were no morphological differences on the X-ray fluoroscopic view. There were no differences in echocardiographic values, except for several values in the left ventricle traces. Overall, it is expected that the values measured in this study will contribute to understanding of the physiological characteristics of micropigs.  相似文献   
104.
The phosphorylation of c-Jun NH (2)-terminal protein kinase (JNK), one of the mitogen-activated protein kinases, was analyzed in the sciatic nerves of Lewis rats with experimental autoimmune neuritis (EAN). Western blot analysis showed that the expression levels of both phosphorylated JNK1 (p-JNK1, approximately 46 kDa) and phosphorylated JNK2 (p-JNK2, approximately 54 kDa) in the sciatic nerves of rats with EAN increased significantly (p < 0.05) at day 14 post-immunization (PI) and remained at this level at days 24 and 30 PI, with a slight decrease. In EAN-affected sciatic nerves, there was intense immunostaining for p-JNK in the infiltrating inflammatory cells (especially ED1-positive macrophages) and Schwann cells on days 14-24 PI, compared with those of controls. Some macrophages with increased p-JNK immunoreactivity was shown to be apoptotic, while some Schwann cells remained survived in this rat EAN model, suggesting that JNK is differentially involved in the EAN-affected sciatic nerves. These findings suggest that JNK phosphorylation is closely associated with the clearance of inflammatory cells as well as the activation of Schwann cells in the EAN affected sciatic nerves.  相似文献   
105.
Phylogenetic relationships among Bornean sucker fishes (Teleostei: Balitoridae: Gastromyzontinae) were investigated by comparing cytochrome b gene sequences from eight species. The results were in general agreement with previous morphology‐based studies. It was found that the genera Gastromyzon and Neogastromyzon are both monophyletic and that the Chinese homalopterid Crossostoma lacustre (Homalopterinae) is not related to the Bornean species. This molecular‐level study of cytochrome b gene variation in Bornean gastromyzontins will undoubtedly help to shed light on the molecular systematics of this unique freshwater fish.  相似文献   
106.
107.
聚丙烯酰胺防治坡地水土流失田间试验研究   总被引:14,自引:1,他引:13  
坡地篱用聚丙烯酰胺可以减少地表径流,提高土壤含水量,促进土壤沉降,增强土壤结构性和水稳性,因而提高了土壤的持水性和抗蚀性,减少了土壤侵蚀量和肥力流失量,有利于作物增产。施用聚丙烯酰胺可使产量增加18.7%~32.4%。施用聚丙烯酰胺对环境无不良影响,而且投入费用较低,是一条值得探索的防治坡地水土流失的新途径。  相似文献   
108.
The toxicity of formulations of oil of cassia, Cinnamomum cassia Blume, (20 and 50 g L(-1) sprays and 100% oil-based fumigant) to adult Dermatophagoides farinae Hughes and D. pteronyssinus Trouessart was examined using contact and vapour-phase toxicity bioassays. Results were compared with the lethal activity of three commercial acaricides: benzyl benzoate, dibutyl phthalate and diethyl-m-toluamide (deet). The contact toxicity of cassia oil to both dust mite species was comparable with that of benzyl benzoate but was higher than that of the other two acaricides. Sprays containing 20 and 50 g L(-1) cassia oil were effective against both mite species when applied to fabric, glass, paper, plastic, tin or wood substrates. Applications of the 50 g L(-1) spray to different space volumes and surface areas determined that 50-60 mg of cassia oil was needed to control dust mites in 3.4 m(3) or in 1 m(2). In tests with fumigant devices, toxicity varied according to the thickness of non-woven fabric covering the device, the exposure time, the number of fumigant devices used and the volume of the space sprayed. Fumigant toxicity to adult D. pteronyssinus was more pronounced with devices enclosed in thinner (40 microm) versus thicker (45 or 50 microm) non-woven fabric covers. A single fumigant device with a 40 microm thick non-woven fabric cover resulted in substantial control in a space of 0.05 m(3) but exhibited only moderate to weak control in spaces >or= 0.097 m(3) at 4 days after application. Two fumigant devices gave 88% mortality in a space of 1.73 m(3). Cassia oil applied as sprays or in fumigant devices appears to provide effective protection of humans from house dust mites.  相似文献   
109.
110.
Information was stored as quantum phase in an N-state Rydberg atom data register. One or more flipped states stored in an eight-state atomic wave packet could be retrieved in a single operation, in agreement with a recent proposal by Grover.  相似文献   
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