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101.
采用快速PCR扩增,探索其法医学应用价值.将AmpFLSTRIdentifiler试剂盒分别与4种不同的快速PCR检测试剂联合构建快速PCR体系,以9947A为模板,采用各自优化的循环参数进行扩增,并将各分型结果与常规方法进行比较,结果表明:联合构建的4种快速PCR体系均可获得与常规方法一致的DNA分型结果,扩增用时最短可减少至22 min.可见应用快速PCR方法进行扩增,可获得与常规方法一致的STR分型,并且显著缩短扩增时间,提高DNA分型速率.  相似文献   
102.
目的:克隆p53基因的启动子,插入萤光素酶报告基因载体,并检测启动子活性。方法:采用PCR技术从人肝癌细胞系HepG2基因组中扩增人p53启动子,插入萤光素酶报告基因载体pGL4.0-empty,将重组质粒转染293T、ZR75-1、HepG2、A549细胞,测定p53启动子的转录活性。结果:构建了p53启动子的萤光素酶报告基因;通过测序及质粒酶切鉴定,所构建的p53启动子正确;活性实验表明,报告基因在多种细胞中显示构建的p53启动子活性,并呈现一定的剂量效应;转录因子USF能以剂量效应方式提高p53报告基因的转录活性。结论:克隆了人p53启动子,为进一步研究调控p53的转录因子奠定了基础。  相似文献   
103.
104.
Silkworm hemolymph (SH) was found to exhibit anti-apoptotic activities in mammalian and insect cell systems. An anti-apoptotic mechanism of SH was investigated in a staurosporine-induced HeLa cell using flow cytometry, caspase assay, Immunoblot, and Immunochemistry. The addition of 5% SH to the medium resulted in lower intracellular activities of caspase-3 and caspase-9 after 0.6 μM of staurosporine treatment; however, SH did not directly inhibit the activities of those enzymes. This suggests SH inhibits the event upstream of these caspase activation steps, such as mitochondrial level events. We found from Immunoblot and Immunochemistry that cytochrome c release from the mitochondria was blocked by SH. SH also inhibited Bax translocation to the mitochondria. On the contrary, SH did not block the apoptosis when Bax is not involved in promoting apoptosis. With these results, we propose that SH protects mitochondria from apoptosis signal via blocking Bax translocation, and the subsequent apoptotic events are then inhibited. The inhibition of apoptosis using SH and its components may lead to new approaches for the minimization of cell death during commercial animal cell cultures.  相似文献   
105.
Alzheimer’s disease (AD) is the most common cause of dementia worldwide and mainly characterized by the aggregated β-amyloid (Aβ) and hyperphosphorylated tau. FLZ is a novel synthetic derivative of natural squamosamide and has been proved to improve memory deficits in dementia animal models. In this study, we aimed to investigate the mechanisms of FLZ’s neuroprotective effect in APP/PS1 double transgenic mice and SH-SY5Y (APPwt/swe) cells. The results showed that treatment with FLZ significantly improved the memory deficits of APP/PS1 transgenic mice and decreased apoptosis of SH-SY5Y (APPwt/swe) cells. FLZ markedly attenuated Aβ accumulation and tau phosphorylation both in vivo and in vitro. Mechanistic study showed that FLZ interfered APP processing, i.e., FLZ decreased β-amyloid precursor protein (APP) phosphorylation, APP-carboxy-terminal fragment (APP-CTF) production and β-amyloid precursor protein cleaving enzyme 1 (BACE1) expression. These results indicated that FLZ reduced Aβ production through inhibiting amyloidogenic pathway. The mechanistic study about FLZ’s inhibitory effect on tau phosphorylation revealed t the involvement of Akt/glycogen synthase kinase 3β (GSK3β) pathway. FLZ treatment increased Akt activity and inhibited GSK3β activity both in vivo and in vitro. The inhibitory effect of FLZ on GSK3β activity and tau phosphorylation was suppressed by inhibiting Akt activity, indicating that Akt/GSK3β pathway might be the possible mechanism involved in the inhibitory effect of FLZ on tau hyperphosphorylation. These results suggested FLZ might be a potential anti-AD drug as it not only reduced Aβ production via inhibition amyloidogenic APP processing pathway, but also attenuated tau hyperphosphoylation mediated by Akt/GSK3β.  相似文献   
106.
Hepatic ischemia‐reperfusion (IR) injury is a common clinical problem and ROS may be a contributing factor on IR injury. The current study evaluates the potential protective effect of saffron ethanol extract (SEE) in a rat model upon hepatic IR injury. Caspases 3 and terminal deoxynucleotidyl transferase‐mediated dUTP biotin nick end labeling (TUNEL) results showed increased cell death in the IR samples; reversely, minor apoptosis was detected in the SEE/IR group. Pretreatment with SEE significantly restored the content of antioxidant enzymes (SOD1 and catalase) and remarkably inhibited the intracellular ROS concentration in terms of reducing p47phox translocation. Proteome tools revealed that 20 proteins were significantly modulated in protein intensity between IR and SEE/IR groups. Particularly, SEE administration could attenuate the carbonylation level of several chaperone proteins. Network analysis suggested that saffron extract could alleviate IR‐induced ER stress and protein ubiquitination, which finally lead to cell apoptosis. Taken together, SEE could reduce hepatic IR injury through modulating protein oxidation and our results might help to develop novel therapeutic strategies against ROS‐caused diseases.  相似文献   
107.
Cervix cancer is the second most common cancer among women worldwide, whereas paclitaxel, the first line chemotherapeutic drug used to treat cervical cancer, shows low chemosensitivity on the advanced cervical cancer cell line. Tanshinone IIA (Tan IIA) exhibited strong growth inhibitory effect on CaSki cells (IC50 = 5.51 μM) through promoting caspase cascades with concomitant upregulating the phosphorylation of p38 and JNK signaling. Comprehensive proteomics revealed the global protein changes and the network analysis implied that Tan IIA treatment would activate ER stress pathways that finally lead to apoptotic cell death. Moreover, ER stress inhibitor could alleviate Tan IIA caused cell growth inhibition and ameliorate C/EBP‐homologous protein as well as apoptosis signal‐regulating kinase 1 mediated cell death. The therapeutic interventions targeting the mitochondrial‐related apoptosis and ER stress responses might be promising strategies to conquer paclitaxel resistance.  相似文献   
108.
The International Plant Proteomics Organization (INPPO) is a non‐profit organization whose members are scientists involved or interested in plant proteomics. Since the publication of the first INPPO highlights in 2012, continued progress on many of the organization's mandates/goals has been achieved. Two major events are emphasized in this second INPPO highlights. First, the change of guard at the top, passing of the baton from Dominique Job, INPPO founding President to Ganesh Kumar Agrawal as the incoming President. Ganesh K. Agrawal, along with Dominique Job and Randeep Rakwal initiated the INPPO. Second, the most recent INPPO achievements and future targets, mainly the organization of first the INPPO World Congress in 2014, tentatively planned for Hamburg (Germany), are mentioned.  相似文献   
109.
叶红  张云安  崔敏  吴进荣  刘德胜 《生物磁学》2013,(34):6757-6760
目的:观察不同剂量地佐辛用于腹腔镜妇科手术超前镇痛的效果。方法:将90例ASAI.II级、年龄18~60岁拟行腹腔镜妇科手术的患者随机分成3组,每组30例,A组给予地佐辛0.1mg/kg开皮前15rain静脉注射;B组给予地佐辛0.15mg/kg开皮前15min静脉注射;C组给予地佐辛0.2mg/kg开皮前15min静脉注射,采用VAS评分评估术后镇痛效果并观察术后辅助镇痛药物的使用和不良反应的发生情况。结果:B、c组术后2、4、6、8h的VAS评分明显低于A组(P〈0.05);C组术后2、4h的Ramsay评分明显高于A、B组(P〈0.05);A组术后辅助镇痛药的使用率明显高于B组和C组(P/0.05);3组不良反应的发生率比较均无统计学差异(P〉0.05)。结论:开皮前15rain静注地佐辛0.15mg/kg用于腹腔镜妇科手术镇痛效果好,且不增加不良反应的发生率。  相似文献   
110.
目的:研究PCI术后是否应用依诺肝素抗凝治疗对患者临床疗效的影响。方法:于2011年5月至2012年1月间,连续入选在我院行冠状动脉造影并置入了支架的患者158例,将符合标准的患者随机分为非抗凝组或抗凝组两组各79名。非抗凝组术后常规应用阿司匹林和氯吡格雷。抗凝组术后加用依诺肝素。对入选患者进行院内随访记录其主要心脏不良事件及出血事件。结果:支架植入成功率100%。术后抗凝组113处病变共置入支架135枚;非抗凝组109处病变置入支架115枚。院内随访:主要心脏不良事件和严重出血差异无统计学意义。小出血事件抗凝组多于非抗凝组(P=0.007)。结论:冠状动脉支架置入术后非抗凝治疗组缺血不良事件发生率较抗凝组无明显增加,小出血并发症明显减少。该研究结果表明,对PCI术无特殊并发症的患者术后无需常规抗凝治疗。  相似文献   
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