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81.
目的:应用快速蛋白液相色谱(FPLC)系统从肝癌组织中分离和纯4EHSP70-肽复合物,并研究其对肝癌细胞系HepG-2增殖的影响.方法:将组织进行匀浆、高速离心提取总蛋白后依次进行ConA-Sepharose亲和层析和 DEAE-Sephacel子交换层析分离纯化,所得蛋白经SDS-聚丙烯酰胺凝胶电泳和Western blot进行蛋白分子质量及性质鉴定,Bradford 法测定蛋白浓度;利用MTT方法检测HSP70- 肽复合物对HepG-2细胞增长的情况.结果:分离、纯化得到的蛋白经SDS-聚丙烯酰胺凝胶电泳、考马斯量蓝鉴定为单一带, 分子质量为70 kDa;Western blot结果证实为 HSP70,每10 g组织最终获得1.5 mg的HSP70; HSP70刺激组12,48,72 h与对照组的A值之间有显著差异(0.1 mg/L:t=-0.2500,P=0.00; t=-0.1777,P=0.001:t=-0.3094,P=0.001; 0.5 mg/L:t=-0.2878,P=0.00;t=-0.2044,P= 0.00;t=-0.3285,P=0.00;1 mg/L:t=-0.3118, P=0.00;t=-0.2592,P=0.00;t=-0.1994, P=0.025;5 mg/L:t=-0.4007,P=0.00;t= -0.1302,P=0.016;t=-0.2537,P=0.005),细胞存活率明显高于对照组(P<0.01).结论:使用本分离纯化方法可获得高纯度 HSP70肽复合物;HSP70肽复合物可以促进 HepG-2细胞的生长.  相似文献   
82.
为研究苦瓜蛋白对凋亡的关键酶半胱天冬酶 3及凋亡的调节作用 ,用已经建立起来的方法从苦瓜果肉中提取苦瓜蛋白。将BALB/C小鼠分为 4组 :病毒对照组、正常对照组、药物对照组和药物治疗组 ,分别在第 0天、第 3天、第 7天和第 14天各处死 5只小鼠 ,第 2 1天全部处死动物 ,心肌组织半胱天冬酶 3活性测定按照CAL BIOCHEM公司的试剂说明书进行 ,并稍加改正 ,凋亡鉴定按照Oncogene公司的TdT DNA裂解片断末端原位标记试剂说明书进行。结果发现 ,①病毒对照组第 7天开始出现半胱天冬酶 3活性 (0 .6 3± 0 .2 1pmol/min ,n =5 ) ,第 14天的活性 (10 .9± 1.5pmol/min ,n =5 )显著高于第 7天 ,第 2 1天的活性 (12 .6± 1.3pmol/min ,n =5 )又高于第 14天。②药物治疗组 ,只有一个第 2 1天的标本有半胱天冬酶 3活性 (0 .4 1pmol/min) ,其它两组均未检测到此酶的活性。③DNA裂解片断末端原位标记法发现 ,病毒对照组在第 7天心肌中有少数细胞凋亡 ,第 14天、第 2 1天凋亡细胞明显增多 ,在非病变区域可发现单个凋亡的心肌细胞。治疗组未发现凋亡细胞 ,其它两组也未发现凋亡细胞。结果提示 ,CVB3病毒性心肌炎中发现有明显的凋亡现象 ,凋亡和半胱天冬酶 3发现于第 7天 ,且随着时间增加而逐渐加重(增强 ) ;苦瓜蛋白可显  相似文献   
83.
Effective edge oxidation of graphene with high structural integrity is highly desirable yet technically challenging for most practical applications. In this work, we have developed a green and facile strategy to obtain edge-oxidized graphene with good dispersion stability and high electrical conductivity by exploiting high edge reactivity of highly conductive multi-layer graphene and oxidizing radicals (SO4˙) generated from sodium persulfate (Na2S2O8) with ferrous ion (Fe2+) activation. Owing to high structural integrity of pristine graphene and effective edge oxidation, the obtained edge-oxidized graphene exhibited excellent dispersion stability and satisfactory electrical conductivity (i.e. ≥240 S cm−1). Moreover, the oxidation degree of pristine graphene can be well controlled by adjusting treatment time. The obtained edge-oxidized graphene is expected to find a variety of applications in many fields of anti-static films, energy storage materials, flexible sensors and high-performance nanocomposites.

A green and facile strategy is represented to obtain edge-oxidized graphene by exploiting sulfate radicals generated from Na2S2O8 with Fe2+ activation.  相似文献   
84.
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86.
目的 探讨循证护理在产妇分娩中的临床应用效果.方法 选取2012年3月至2013年8月来我院分娩的180例产妇作为研究对象,将所有产妇按照随机数字表分为两组,其中,观察组90例产妇采用循证护理措施,对照组90例产妇使用常规护理方法,比较两组产妇的分娩方式和产后出血率、新生儿窒息率,并比较两组产妇的产程时间.结果 护理后,观察组产妇的剖宫产率仅为24.4%,明显低于对照组产妇,而观察组产妇的阴道分娩率则为61.1%,明显高于对照组产妇,而且观察组产妇的产后出血率和新生儿窒息率也明显低于对照组产妇,组间差异有统计学意义(P<0.05),观察组产妇的第一产程、第二产程以及第三产程时间均明显低于对照组产妇,组间差异有统计学意义.结论 循证护理措施有利于增强产妇分娩信心,提高产妇阴道分娩成功率,减少剖宫产率,从而降低产后母婴并发症,大大提高了产妇的生活质量,值得临床应用.  相似文献   
87.
There is a 3-aa insertion in the transmembrane (TM) domain of the p68gag-ros protein-tyrosine kinase encoded by avian sarcoma virus UR2 v-ros as compared with that of the protooncogene c-ros. The effect of this insertion on biological function and biochemical properties of v-Ros protein was investigated by deleting these 3 aa to generate the mutant TM1. This mutant has greatly reduced transforming, mitogenic, and tumorigenic activities despite the fact that the protein-tyrosine kinase activity and cell-surface localization of TM1 protein are unaffected. However, unlike UR2 protein, mutant TM1 protein becomes glycosylated, is differentially phosphorylated, and fails to induce tyrosine phosphorylation of a 88-kDa protein and a major substrate of insulin receptor, insulin receptor substrate 1. The TM1 protein is unable to associate with phosphatidylinositol 3-kinase and fails to promote association of insulin receptor substrate 1 with phosphatidylinositol 3-kinase. By contrast, tyrosine phosphorylation of Shc protein and phospholipase C gamma as well as interaction of Grb2 protein with Shc and SOS protein signaling components are unaltered in the TM1 infected cells. Our results show that the TM-domain sequence of p68gag-ros profoundly affects its function and substrate interaction. The mutant defines a signaling pathway including phosphatidylinositol 3-kinase, insulin receptor substrate 1, and possibly an 88-kDa protein that does not overlap the Ras pathway and is important for full transforming and mitogenic potency of v-ros protein-tyrosine kinase.  相似文献   
88.
Polygonatum sibiricum polysaccharide (PSP) is a traditional Chinese medicine and is widely used to treat many diseases for hundreds of years conventionally. This study was to access the effects of PSP on the osteogenic differentiation of bone marrow mesenchymal stem cells (BMSCs) in the mice. Cells collected from BALB/C mice in the bone marrow were isolated and cultured with osteogenic medium (OM) with different concentrations of PSP. The proliferation and morphological changes of BMSCs were observed using an inverted microscope. Flow cytometric analysis was used to identify the BMSCs. MTT test was performed to analyze the proliferation and viability of the cells. ELISA was used to determine the expression levels of alkaline phosphatase (ALP), osteocalcin (OC), N-terminal propeptide of type I procollagen (PINP) and bone morphogenetic protein-2 (BMP-2). Immunocytochemistry and western blot were respectively used to determine the expressions of bone sialoprotein (BSP) and SPARC/osteonectin (OSN). The growth curves of the proliferation and differentiation of the Control, OM, 17β-E2 and PSP groups were increased. Compared to the Control and OM groups, the expression levels of ALP, OC, PINP and BMP-2 were significantly increased in the PSP induced group (P<0.05). Immunocytochemistry and western blot showed that BSP and SPARC were increased after induction of PSP compared to the OM group (P<0.05). The study demonstrates that PSP promotes the proliferation and enhances the viability of BMSCs during osteogenic differentiation. Therefore, PSP may be a potential treatment of osteoporosis in the clinic.  相似文献   
89.
This study aimed to screen the potential diagnostic biomarkers for distinguishing the malignant pheochromocytoma (PCC) from benign PCC. A total of 59 patients with PCC (benign and malignant) were enrolled in this study. The expression level of miRNAs in patients with different kind PCCs (healthy control, benign, malignant, malignant with or without SDHD mutation, adrenal and extra-adrenal) was analyzed using the qRT-PCR analysis. Besides, the diagnosis accuracy of miRNA in PCC samples was analyzed using the ROC analysis. Moreover, level of miR-101 in serum was detected by qRT-PCR analysis and serum VEGF level in patients with PCC was detected using the ELISA kit. Compared with benign PCC, miR-101 level was higher in patients with malignant PCC (P < 0.05), while the level of miR-513-5p and miR-26b showed no difference between malignant PCC and benign PCC (P > 0.05). miR-101 expression was significantly increased in malignant tumor tissue with SDHD mutation (P < 0.05) and in extra-adrenal tissues (P < 0.05), respectively. Besides, AUCs for miR-101 in PCC samples was 0.79 and for which in PCC samples with non-SDHD mutation was 0.77. Besides, serum miR-101 in malignant PCC was high but showed no difference among groups (P > 0.05). Moreover, serum VEGF level in malignant tumors was significantly high compared with benign tumor, as well as that in malignant PCC with SDHD mutation (P < 0.05). Our study suggested that SDHD mutation may enhance the overexpression of miR-101 in malignant tumors and miR-101 may be a potential diagnostic biomarker for malignant PCC and benign PCC.  相似文献   
90.
A Salmonella enterica serovar Corvallis strain was isolated from a wild bird in Germany. This strain carried the IncA/C2 pRH-1238 plasmid. Complete sequencing of the plasmid was performed, identifying the blaNDM-1, blaCMY-16, fosA3, sul1, sul2, strA, strB, aac(6)-Ib, aadA5, aphA6, tetA(A), mphA, floR, dfrA7, and merA genes, which confer clinically relevant resistance to most of the antimicrobial classes, including β-lactams with carbapenems, fosfomycin, aminoglycosides, co-trimoxazole, tetracyclines, and macrolides. The strain likely originated from the Asiatic region and was transferred to Germany through the Milvus migrans migratory route.  相似文献   
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