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11.
12.
目的:比较异丙酚和氯胺酮对大鼠离体缺血再灌注损伤心肌脂质过氧化的影响。方法:成年Wistar大鼠18只,雌雄不拘。体重240-300g,随机分为3组(T1=6):心肌缺血再灌注损伤组(I/R组),异丙酚组(P组),氯胺酮组(K组)。采用Langendorff灌装置建立离体心脏缺血再灌注模型,将心脏连接至Langendorff逆灌装置,3组均以K-H液平衡灌注10min后,再分别以K.H液、含30μmol/L。异丙酚的K-H液、含10μmol-L-1氯胺酮的K-H液灌注10min,然后全心停灌25min,再分别以停灌前相同的灌注液恢复灌注30min。留取冠脉流出液测定总LDH活性;灌注末取左室心肌组织置于2.5%的戊二醛固定,观察心肌的超微结构;心尖部心肌组织留待检测8-异前列腺素和SOD活性。结果:与I/R组比较,P组8-异前列腺素含量降低,SOD活性升高,LDH活性降低(P〈0.05);K组8-异前列腺素含量,SOD及LDH活性均无统计学意义(P〉0.05);与P组比较,K组8-异前列腺素含量升高,SOD及LDH活性降低(P〈0.05);P组心肌超微结构损伤较m组和K组也明显改善。结论:异丙酚可显著减轻心肌缺血再灌注损伤大鼠的脂质过氧化和心肌缺血再灌注损伤,而氯胺酮没有抗心肌缺血再灌注损伤心肌脂质过氧化的作用。  相似文献   
13.
目的:探讨新生儿肺炎(neonatal pneumonia,NP)的临床表现及x线特征,以提高对NP的临床认识。方法:选择2011年6月至2012年10月在我院确诊为NP的新生儿73例,均经x线检查,回顾性分析患儿的临床资料,总结并分析患儿的临床表现及x线特征。结果:NP患儿的临床症状主要表现为呼吸急促、发绀、咳嗽、吐沫、呛奶和三凹征,部分患儿体温正常;NP的x线影像表现具有多样性,以不同程度的支气管肺炎多见,主要表现为肺纹理增多增密,局部肺野透光度降低或透光度增强。结论:NP患儿的临床症状以呼吸急促、发绀、咳嗽、吐沫、呛奶和三凹征为主,x线检查可为NP的早期诊断提供重要的临床信息,临床医师应根据NP患儿的x线影像的多样性,密切结合患儿的临床症状,做出综合分析。  相似文献   
14.
Mitochondrial retrograde regulation (MRR) is the transduction of mitochondrial signals to mediate nuclear gene expression. It is not clear whether MRR is a common regulation mechanism in plant abiotic stress response. In this study, we analysed the early abiotic stress response of the rice OsAOX1 genes, and the induction of OsAOX1a and OsAOX1b (OsAOX1a/b) was selected as a working model for the stress‐induced MRR studies. We found that the induction mediated by the superoxide ion (O)‐generating chemical methyl viologen was stronger than that of hydrogen peroxide (H2O2). The addition of reactive oxygen species (ROS) scavengers demonstrated that the stress induction was reduced by eliminating O. Furthermore, the stress induction did not rely on chloroplast‐ or cytosol‐derived O. Next, we generated transgenic plants overexpressing the superoxide dismutase (SOD) gene at different subcellular locations. The results suggest that only the mitochondrial SOD, OsMSD, attenuated the stress induction of OsAOX1a/b specifically. Therefore, our findings demonstrate that abiotic stress initiates the MRR on OsAOX1a/b and that mitochondrial O is involved in the process.  相似文献   
15.
N6-METHYLADENINE (6-MeAde) and 5-methylcytosine occur as minor bases in bacterial and phage DNA1–7 and seem to result from the selective methylation of adenine and cytosine residues by specific DNA methylases8. Methylation is the final stage in DNA synthesis and is essential for the phenomenon of host modification of phages9–11; it is one of the mechanisms controlling DNA replication in the cell12, 13. A study of the distribution of minor bases in DNA is therefore important not only for the elucidation of the specificity and mechanism of action of DNA methylases but also for an understanding of the purpose of this methylation. We believe that in Escherichia coli, DNA methylase exerts its action on adenine residues in chain terminating triplets: 6-MeAde may serve as a signal for gene termination in this system.  相似文献   
16.
1979年9月在沈阳地区的翅果油树 Elaeagnus mollis 植株上发现壳多孢属的一个新种,定名为胡颓子壳多孢(Stagonospora elaeagni Y.Gao sp.nov.)。  相似文献   
17.
INTRODUCTIONOpioidreceptorsbelongtotheG-protein-coupledreceptorfamilythatischaracterizedbytheseventransmembranespanningdomainsinstructure.Threesubtypesoftheopioidreceptors(H,6,andK)havebeenclonedandcharacterizedthroughtheir1.CorrespondingauthorFunctionalexpressionofORLIandN/OFQduringmouseembryogenesisdistinctaffinitiesfordifferentopioidligands.TheseopioidreceptorsareallcoupledtotheinhibitoryGprotein(Gi)andnegativelyregulateadenylatecyclase[1].Opioidreceptor--likereceptor(ORLI),anew…  相似文献   
18.

Background

Malaria greatly impacts the health and wellbeing of over half of the world''s population. Promising malaria vaccine candidates have attempted to induce adaptive immune responses to Circumsporozoite (CS) protein. Despite the inclusion of potent adjuvants, these vaccines have limited protective efficacy. Conventional recombinant adenovirus (rAd) based vaccines expressing CS protein can induce CS protein specific immune responses, but these are essentially equivalent to those generated after use of the CS protein subunit based vaccines. In this study we combined the use of rAds expressing CS protein along with rAds expressing novel innate immune response modulating proteins in an attempt to significantly improve the induction of CS protein specific cell mediated immune (CMI) responses.

Methods and Findings

BALB/cJ mice were co-vaccinated with a rAd vectors expressing CS protein simultaneous with a rAd expressing either TLR agonist (rEA) or SLAM receptors adaptor protein (EAT-2). Paradoxically, expression of the TLR agonist uncovered a potent immunosuppressive activity inherent to the combined expression of the CS protein and rEA. Fortunately, use of the rAd vaccine expressing EAT-2 circumvented CS protein''s suppressive activity, and generated a fivefold increase in the number of CS protein responsive, IFNγ secreting splenocytes, as well as increased the breadth of T cells responsive to peptides present in the CS protein. These improvements were positively correlated with the induction of a fourfold improvement in CS protein specific CTL functional activity in vivo.

Conclusion

Our results emphasize the need for caution when incorporating CS protein into malaria vaccine platforms expressing or containing other immunostimulatory compounds, as the immunological outcomes may be unanticipated and/or counter-productive. However, expressing the SLAM receptors derived signaling adaptor EAT-2 at the same time of vaccination with CS protein can overcome these concerns, as well as significantly improve the induction of malaria antigen specific adaptive immune responses in vivo.  相似文献   
19.
目的:探讨与研究三磷酸腺苷结合盒转运体A1 (Adenosine triphosphate (ATP)-binding cassette transporter A1)基因多态性R219K与帕金森症(Parkinson disease,PD)和阿尔兹海默症(Alzheimer disease,AD)发病率的相关性。方法:选择2016年2月到2019年8月在本院门诊与住院的帕金森症患者42例作为PD组,同期选择本院门诊与住院的阿尔兹海默症患者42例作为AD组,同期选择本院门诊健康体检者84例作为对照组。调查入选者的一般资料,检测三组血液样本的ABCA1基因多态性R219K情况并进行相关性分析。结果:AD组低密度脂蛋白(low-density lipoprotein,LDL-C)、总胆固醇(total cholesterol,TC)、甘油三酯(triglyceride,TG)与尿酸(Uric acid,UA)均低于对照组,而高密度脂蛋白(high-density lipoprotein,HDL-C)、同型半胱氨酸(homocysteine,Hcy)值高于对照组(P0.05);AD组TC均低于PD组,而HDL高于PD组。PD患者HDL-C均低于对照组,而LDL、TC和TG与对照组无差异(P0.05),三组空腹血糖(Fasting blood glucose,FBG)值对比差异无统计学意义(P0.05)。PD组与AD组的ABCA1 R219K GA基因型、A等位基因频率都显著高于对照组(P0.05),PD组与AD组对比差异无统计学意义(P0.05)。在168例入选者中,直线相关分析显示ABCA1 R219K GA基因型与A等位基因与帕金森症或阿尔兹海默症发生有显著相关性(P0.05)。结论:ABCA1基因多态性R219K在帕金森症和阿尔兹海默症患者中比较常见,ABCA1 R219K GA基因型与A等位基因可诱发帕金森症和阿尔兹海默症的发生。  相似文献   
20.
目的:探讨患者创伤后发生急性肾损伤的患者发病率、临床特点以及发病危险因素,以便有效预防和及早治疗。方法:回顾性分析我院重症监护室2004年1月至2010年12月收治的创伤患者相关临床资料,分析创伤后急性肾损伤的发病率以及发病危险因素。结果:共有106例患者纳入我们的研究,其中47例患者创伤后并发急性肾损伤。在发生急性肾损伤患者中,平均年龄为31±19岁,84.6%为男性;其中25例为脓毒血症引起,18例是因为低血压导致急性肾功能损伤。所有患者中,24例患者出现了少尿的症状,19例患者进行了透析治疗。腹部外伤[(OR)=3.66,P=0.027]和应用呋塞米[(OR=4.10,P=0.026)]是发生急性肾损伤的危险因素。结论:急性肾损伤时创伤后的严重并发症之一,死亡率高。只有找到创伤后发生急性肾损伤的危险因素,才能有效预防和及早治疗。  相似文献   
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