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991.
目的:通过对冠心病患者经皮冠状动脉介入治疗(PCI)前后血清Caspase-3,9水平变化的观察,探讨冠状动脉介入治疗对冠心病患者血清Caspase-3,9水平的影响。方法:冠状动脉介入组(PCI组)30例和单纯造影组(CAG组)29例,在术前0.5h,术后3h,术后6h,术后12h,术后24h,术后48h分别测定血清Caspase-3,9水平。结果:CAG组术前与术后的血清Caspase-3,9水平差异均无统计学意义,PCI组术后3h、6h的Caspase-3水平较术前0.5h均有降低趋势,差异均有统计学意义(P<0.05),PCI组术后48h的Caspase-9水平与术后3h、6h相比均有升高趋势,差异均有统计学意义(P<0.05)。结论:PCI术后狭窄或闭塞的冠状动脉血管重新恢复血供,血清中Caspase-3,9水平在PCI术后先降低后又逐渐升高,提示再灌注后可出现细胞的凋亡程度加重,血清中Caspase-3,9的水平可作为心肌再灌注损伤后细胞凋亡程度的评估指标并可作为诊断临床症状不典型的再灌注损伤的一个指标。PCI术可有效改善心肌血供,减少因术前缺血缺氧造成的细胞凋亡,但PCI术后再灌注损伤可进一步加重细胞凋亡。 相似文献
992.
目的:观察他汀类调脂药物瑞舒伐他汀(Rosuvastatin)对2型糖尿病(type2diabetesmellitus,T2DM)大鼠早期动脉粥样硬化形成的影响,并探讨其可能的机制。方法:将45只雄性SD大鼠随机分为正常对照组(NC组)、2型糖尿病组(DM组)、2型糖尿病瑞舒伐他汀治疗组(DR组),每组15只。以喂高糖高脂饮食方法建立SD大鼠糖尿病模型,DM组、DR组给予高糖高脂饮食1个月后腹腔注射25mg/kg链脲佐菌素;NC组给予普通饮食,注射枸橼酸缓冲液作为对照。在此基础上,DR组给予瑞舒伐他汀5mg/(kg.d)灌胃,NC组、DM组给予生理盐水灌胃。16周后测定各组大鼠总胆固醇(TC)、三酰甘油(TG)、低密度脂蛋白胆固醇(LDL-C)水平与稳态血糖(BG)、稳态胰岛素(PGI)浓度,用免疫组化法检测主动脉血管壁白细胞分化抗原40(clusterofdifferentiation 40,CD40)及基质金属蛋白酶-2(MMP-2)、激活蛋白-1(activator protein-1,AP-1)的表达水平。结果:DM组、DR组TC、TG、LDL-C与BG水平较NC组均显著升高(F=33.71~426.... 相似文献
993.
Jiu-ru Zhao Yong-dong Li Li-min Pan Na Zhu Hong-xia Ni Guo-zhang Xu Yong-zhong Jiang Xi-xiang Huo Jun-qiang Xu Han Xia Na Han Shuang Tang Zhong Zhang Zheng Kou Simon Rayner Tian-xian Li 《中国病毒学》2011,26(6):418-427
A total of 100 HIN1 flu real-time-PCR positive throat swabs collected from fever patients in Zhejiang,Hubei and Guangdong between June and November 2009,were provided by local CDC laboratories.After MDCK cell culture,57 Influenza A Pandemic (H1N1) viruses were isolated and submitted for whole genome sequencing.A total of 39 HA sequences,52 NA sequences,36 PB2 sequences,31 PB1 sequences,40 PA sequences,48 NP sequences,51 MP sequences and 36 NS sequences were obtained,including 20 whole genome sequences.Sequence comparison revealed they shared a high degree of homology (96%~99%) with known epidemic strains (A/Califomia/04/2009(H1N1).Phylogenetic analysis showed that although the sequences were highly conserved,they clustered into a small number of groups with only a few distinct strains.Site analysis revealed three substitutions at loop 220 (221-228) of the HA receptor binding site in the 39 HA sequences:A/Hubei/86/2009 PKVRDQEG→PKVRDQEA,A/Zhejiang/08/2009 PKVRDQEG→PKVRDQER,A/Hubei/75/2009PKVRDQEG→PKVRDQGG,the A/Hubei/75/2009 was isolated from an acute case,while the other two were from patients with mild symptoms.Other key sites such as 119,274,292 and 294 amino acids of NA protein,627 of PB2 protein were conserved.Meanwhile,all the M2 protein sequences possessed the Ser32Asn mutation,suggesting that these viruses were resistant to adamantanes.Comparison of these sequences with other H1N1 viruses collected from the NCBI database provides insight into H1N1 transmission and circulation patterns. 相似文献
994.
本研究对成团泛菌低分子脂多糖(Pantoea agglomerans lipopolysaccharide,LPSp)的安全性进行初步评估.本研究采用一次限量法,用昆明种小鼠进行LPSp急性经口毒性试验,了解LPSp的急性毒性;采用新西兰兔分别进行LPSp急性和多次皮肤刺激性试验以及急性眼刺激性试验,了解LPSp的皮肤和粘膜刺激性;采用豚鼠进行LPSp皮肤变态反应试验,了解LPSp的致敏性;应用平板掺入法进行鼠伤寒沙门氏菌/回复突变试验和小鼠骨髓细胞微核试验考察LPSp的遗传危害.急性毒性试验结果显示,LPSp对小鼠经口一次灌胃的LD50大于5 000 mg/kg体重,属实际无毒级别;LPSp急性和多次皮肤刺激性试验以及急性眼刺激性试验结果显示,皮肤刺激和眼刺激积分均为0分,LPSp对皮肤无刺激性、对眼睛无急性刺激性;在皮肤变态反应试验中,LPSp在各观察时间点的皮肤变态反应积分均为0分,其致敏率均为0%,说明LPSp对豚鼠无致敏性; LPSp的鼠伤寒沙门氏菌/回复突变试验结果呈阴性(P>0.05);LPSp的小鼠骨髓细胞微核试验结果亦呈阴性,LPSp 各剂量组的微核发生率与阴性对照组未见统计学差异(P>0.05),而与阳性对照组有明显差异(P<0.01).本研究结果表明,在本实验剂量范围内,LPSp对小鼠经口毒性极低,属实际无毒级别,对家兔皮肤和眼睛无明显刺激性,对豚鼠无致敏性,对所试菌株和小鼠体细胞无诱变性和致突变性. 相似文献
995.
百合不定芽的快速诱导 总被引:1,自引:0,他引:1
为获得麝香百合组织培养最优外植体及探讨蔗糖、6-BA和NAA的最佳用量,本文以MS固体培养基为基础培养基,通过4因素3水平(L9 (34)) 3次重复正交试验,研究不同花器官及不同浓度的蔗糖、6-BA (6 苄基嘌呤)和NAA (α-萘乙酸)对麝香百合组织培养诱导不定芽的影响.结果表明,花托为诱导不定芽最优外植体,诱导不定芽最佳培养基为MS+6-BA 1.0 mg/L+NAA 0.3 mg/L+蔗糖90 g/L.同时经过分析,可以判断本试验中设计的4个试验因素对百合组培的影响程度依次为外植体>蔗糖>奈乙酸和6-苄氨基嘌呤.本研究结果将为百合优良品种的生产提供重要的技术支撑和资源保证. 相似文献
996.
Wu HJ Yang Y Wang S Qiao JQ Xia YF Wang Y Wang WD Gao SF Liu J Xue PQ Gao XW 《The FEBS journal》2011,278(8):1345-1357
In the present study, we report the identification of a new gene from the Bacillus subtilis B3 strain (aatB3), which comprises 1308 bp encoding a 436 amino acid protein with a monomer molecular weight of 49.1 kDa. Phylogenetic analyses suggested that this enzyme is a member of the Ib subgroup of aspartate aminotransferases (AATs; EC 2.6.1.1), although it also has conserved active residues and thermostability characteristic of Ia-type AATs. The Asp232, Lys270 and Arg403 residues of AATB3 play a key role in transamination. The enzyme showed maximal activity at pH 8.0 and 45 °C, had relatively high activity over an alkaline pH range (pH 7.0-9.0) and was stable up to 50 °C. AATB3 catalyzed the transamination of five amino acids, with L-aspartate being the optimal substrate. The K(m) values were determined to be 6.7 mM for L-aspartate, 0.3 mM for α-ketoglutarate, 8.0 mM for L-glutamate and 0.6 mM for oxaloacetate. A 32-residue N-terminal amino acid sequence of this enzyme has 53% identity with that of Bacillus circulans AAT, although it is absent in all other AATs from different organisms. Further studies on AATB3 may confirm that it is potentially beneficial in basic research as well as various industrial applications. 相似文献
997.
An effective new platform for phosphosite mapping and subsequent functional screening was developed to analyze the targeted protein-protein interactions of p300 and CBP with β-catenin. Two novel functional phosphosites, Ser12 of p300 and Ser92 of CBP, were revealed to modulate p300/β-catenin and CBP/β-catenin interactions, respectively. 相似文献
998.
Rhodanese catalyzes the sulfur-transfer reaction in which a sulfur atom is transferred from thiosulfate to cyanide by a double-displacement mechanism. During the reaction, a persulfide-intermediate form of rhodanese is generated by the reaction of a conserved active cysteine residue with thiosulfate. Escherichia coli GlpE is a prototype for the single-domain rhodanese superfamily. Though there are some studies on rhodaneses, the molecular mechanism of the catalytic activity of rhodaneses is still unclear. Herein, we report the resonance assignments of (1)H, (13)C and (15)N atoms of E. coli GlpE, which provides the basis for further structural, dynamic and functional studies of rhodaneses using NMR technique. 相似文献
999.
One new (1) and seven (2–8) known sesquiterpenoids, four dimeric tryptamine-related alkaloids (9–12) and six glycosides (13–18) were isolated from the fruits and leaves of Chimonanthus praecox (wintersweet). Based on its spectroscopic data, the new structure of compound 1, an oppositane-type sesquiterpenoid, was elucidated to be the C-4 epimer of bullatantriol (2). All isolated compounds were evaluated for their cytotoxicities against a small panel of human cancer cell lines, and only the chimonanthine-type alkaloids (10–12) were found to have cytotoxic effects against gastric carcinoma NUGC3 and hepatocarcinoma SNU739 cancer cells, with IC50 values ranging from 10.3 to 19.7 μM. 相似文献
1000.