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61.
MicroRNA (miRNAs) is demonstrated to be present in the blood of humans and has been increasingly suggested as a novel biomarker for various pathological processes in the heart, including myocardial infarction, myocardial remodeling and progression to heart failure. In this study, we aim to evaluate the diagnostic and prognostic value of circulating miR-328 and miR-134 in patients with acute myocardial infarction (AMI). Circulating levels of miR-328 and miR-134 were detected by quantitative real-time PCR in plasma samples from 359 AMI patients and 30 healthy volunteers. Concentrations of high-sensitivity cardiac troponin T (hs-cTnT) were measured using electrochemiluminescence-based methods. MiRNAs were assessed for discrimination of a clinical diagnosis of AMI and for association with primary clinical endpoint defined as a composite of cardiogenic death and development of heart failure within 6 months after infarction. Results showed that levels of plasma miR-328 and miR-134 were significantly higher in AMI patients than in healthy controls. Receiver operating characteristic curve analyses showed significant diagnostic value of miR-328 and miR-134 for AMI. However, neither of them was superior to hs-cTnT for the diagnosis. Additionally, increased miRNA levels were strongly associated with increased risk of mortality or heart failure within 6 months for miR-328 (OR 7.35, 95 % confidence interval 1.07–17.83, P < 0.001) and miR-134 (OR 2.28, 95 % confidence interval 1.03–11.32 P < 0.001). In conclusion, circulating miR-328 and miR-134 could be potential indicators for AMI, and the miRNA levels are associated with increased risk of mortality or development of heart failure.  相似文献   
62.
内蒙古道虎沟中侏罗世假古蝉属化石(同翅目,古蝉科)   总被引:4,自引:0,他引:4  
王莹  任东 《动物分类学报》2006,31(2):289-293
描述古蝉科化石3新种,即多点假古蝉Pseudocossus punctulosus sp.nov.,美丽假古蝉P.bellus sp.nov.,弯脉假古蝉P.ancylivenius sp.nov..所有标本均采自内蒙古宁城道虎沟中侏罗世九龙山组,其中2个新种保存有完整的臀区.模式标本保存在首都师范大学生命科学学院.  相似文献   
63.
采用超声破碎法和甲醇:二氯乙烷=2:1(v/v)溶剂来萃取小球藻中类胡萝卜素类化合物.分别采用了3种不同的色谱分离方法,最后确定小球藻中类胡萝卜素类化合物的最优色谱分离条件为甲醇(A):乙氰(B)=90:10(v/v),柱温为室温,流速1ml/min.用ZOBAX SB-C18色谱柱和ZOBAX Eclipse plus C18色谱柱进行分离试验时发现,ZOBAX Eclipse plus C18色谱柱的分离效果良好.最后确定小球藻中叶黄素含量为2.312mg/g.  相似文献   
64.
Human umbilical cord-derived mesenchymal stem cells (hUC-MSCs) hold great potential for their therapeutic use in various clinical diseases. Many publications have reported on human blood-derived alternatives to animal serum for culturing mesenchymal stem cells, such as human serum, allogenic umbilical cord blood serum, and human platelet derivatives. However, it is not clear whether human umbilical cord blood plasma (UCBP), as the surplusage of umbilical cord blood mesenchymal stem cell extraction, could be used. In this study, in order to make the best of umbilical cord blood, the human UCBP was dialyzed to replace fetal bovine serum (FBS) in the culture medium. hUC-MSCs were cultured in the new medium. Cell growth rate, specific biomarkers, and differentiation properties were detected to characterize the cell proliferation and MSC-specific properties. The hUC-MSCs cultured in such derived medium were verified with proliferation rate, cluster differentiation markers, cell cycle, as well as differentiation capabilities. Such dialyzed human UCBP is fully comparable with, if not superior to, FBS in deriving and culturing hUC-MSCs.  相似文献   
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67.
Li C  Zheng Y  Wang X  Xia W  Gao H  Li D  Ma X 《Journal of cellular physiology》2011,226(11):2834-2840
Skin and soft tissue expansion stimulates the proliferation of skin epidermal basal cells and increase the dermal collagen deposition and angiogenesis. To explore the contribution of bone marrow‐derived stem cells (BMSCs) to the generation of “new” skin during the expansion, we used a chimeric mouse model in which the donor C57BL mice were engrafted with the bone marrow of enhanced green fluorescent protein (EGFP) transgenic mice. BMSCs were collected from the tibia and femur of EGFP+ transgenic mice, and then injected into normal C57BL mice via the tail vein (chimeric mice). Skin was obtained at different times (days 0, 7, 14, 21, 28, and 35). Skin stromal‐derived factor‐1 (SDF‐1) expression was evaluated. The number, distribution, and phenotype changes of EGFP+ cells in the skin were also evaluated by means of fluorescent microscopy. EGFP+ cells were present stably in the normal skin. The number of EGFP+ cells of the Group A mice changed with the tension, and reached the peak on day 21(17.1 ± 6.7%), as compared with either Group B (5.5 ± 1.0%) or Group C (5.1 ± 0.9%). The SDF‐1 expression in the expanded skin was significant increased (≈11‐fold, P < 0.01) compared to non‐expanded skin on day 21. Immunofluorescence showed EGFP+ cells were converted into vascular endothelial cells, epidermal cells, and spindle‐shaped dermal fibroblasts. Strain can promote the expression of SDF‐1 and facilitate the differentiation and proliferation of BMSCs in the expanded skin. J. Cell. Physiol. 226: 2834–2840, 2011. © 2011 Wiley‐Liss, Inc.  相似文献   
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69.
衣藻质体分裂相关基因CrFtsZ2的克隆及其进化分析   总被引:5,自引:0,他引:5  
FtsZ(filamentingtemperaturesensitive)是一类从大肠杆菌温度敏感型突变体中分离到的基因 .该基因与E .coli细胞分裂密切相关 .突变体由于细胞分裂受阻而呈现“长丝状”[1] .此类基因于 1980年首次被克隆[2 ] .随后的研究表明 ,FtsZ蛋白在E .coli分裂细胞的凹陷处形成环状多聚体 ,Z环 ,是E .coli细胞分裂的限制因子[3 ] .衣藻属于绿藻 ,在现存的所有单细胞真核藻类中 ,绿藻是与陆生植物亲缘关系最近的一支[4] .由于衣藻为单细胞真核生物 ,并且仅含有一个巨大的叶绿体 ,因而是研究…  相似文献   
70.
Chen WB  Wang X  Zhou YL  Dong HY  Lin HR  Li WS 《动物学研究》2011,32(3):285-292
该文采用RT-PCR和cDNA末端快速扩增技术(rapid-amplification of cDNA ends,RACE)的方法,从尼罗罗非鱼(Oreochromis niloticus)下丘脑总RNA中获得了尼罗罗非鱼Orexin前体基因的cDNA全长序列。该cDNA全长648bp,其中开放阅读框的长423bp,编码Orexin前体蛋白为140个氨基酸,包括37个氨基酸的信号肽、43个氨基酸的Orexin-A、28个氨基酸的Orexin-B和末尾32个氨基酸组成的功能不详的多肽。采用Real-time PCR技术对尼罗罗非鱼Orexin前体基因的组织表达模式以及在摄食前后、饥饿和再投喂状态下的表达量变化进行了研究。结果显示,在脑部和外周等18个组织中都检测到了Orexin前体基因的表达,其中在下丘脑中表达量最高;在摄食前后,尼罗罗非鱼Orexin前体基因的表达量显著低于在摄食状态中;饥饿2、4、6和8d后,Orexin前体基因在下丘脑中的表达量与正常投喂组相比均显著升高,饥饿4d再投喂后,表达量又恢复至正常水平。这些结果表明,Orexin在尼罗罗非鱼摄食中可能有着重要的调节作用。  相似文献   
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