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991.
摘要 目的:分析糖化清蛋白、高敏C反应蛋白与冠心病临界病变患者冠脉斑块形态学特征的关系及对功能性心肌缺血的预测价值。方法:选择自2020年1月至2022年6月我院经冠脉造影确诊的165例冠心病临界病变患者作为研究对象,分为不稳定型心绞痛组和稳定型心绞痛组。检测两组血清糖化清蛋白、高敏C反应蛋白表达水平,使用靶血管造影检测冠脉斑块形态学指标,Pearson相关性分析血清糖化清蛋白、高敏C反应蛋白与冠脉斑块形态学指标的关系,通过ROC曲线下面积(AUC)评价血清糖化清蛋白联合高敏C反应蛋白对功能性心肌缺血的预测价值。结果:不稳定型心绞痛组血清糖化清蛋白、高敏C反应蛋白表达水平均高于稳定型心绞痛组(P<0.05);不稳定型心绞痛组最小管腔直径、最小管腔面积均小于稳定型心绞痛组,直径狭窄率、管腔面积狭窄率、斑块面积均大于稳定型心绞痛组(P<0.05);在165例冠心病临界病变患者中,发生冠脉易损斑块53例;易损斑块组血清糖化清蛋白、高敏C反应蛋白表达水平均高于非易损斑块组(P<0.05);经Pearson相关性分析,冠心病临界病变患者血清糖化清蛋白、高敏C反应蛋白表达水平均与最小管腔直径、最小管腔面积呈负相关,与直径狭窄率、管腔面积狭窄率、斑块面积呈正相关(P<0.05);经ROC曲线分析,血清糖化清蛋白联合高敏C反应蛋白预测冠心病临界病变患者发生功能性心肌缺血的AUC为0.910。结论:糖化清蛋白、高敏C反应蛋白与冠心病临界病变患者冠脉斑块形态学特征密切相关,有助于评估冠脉斑块易损性,联合预测功能性心肌缺血的效能较好,值得临床予以重视应用。  相似文献   
992.
摘要 目的:探讨胃癌组织长链非编码核糖核酸(lncRNA)HIT000218960的表达及其与患者临床病理特征及预后的关系。方法:选择2018年1月至2019年6月于中国人民解放军联勤保障部队第九七Ο医院进行手术切除治疗的103例胃癌患者及进行胃粘膜活检的健康体检志愿者62例,取其对应组织,应用逆转录-定量聚合酶链式反应(RT-qPCR)检测组织中lncRNA HIT000218960及高迁移率族蛋白A2(HMGA2)信使RNA(mRNA)表达,应用免疫组织化学法检测组织中HMGA2阳性表达。分析lncRNA HIT000218960表达与胃癌患者临床病理特征的关系。随访3年,应用Kaplan-Meier生存曲线分析不同lncRNA HIT000218960分组患者预后情况,并应用Cox回归分析胃癌患者预后的影响因素。结果:胃癌组织中lncRNA HIT000218960、HMGA2 mRNA表达水平显著高于正常胃粘膜组织(P<0.05),HMGA2蛋白阳性表达率显著高于正常胃粘膜组织(P<0.05)。胃癌组织中lncRNA HIT000218960表达与肿瘤直径、组织分化程度、TNM分期、淋巴结转移显著相关(P<0.05)。lncRNA HIT000218960水平与HMGA2 mRNA表达呈正相关(r=0.462,P<0.05)。lncRNA HIT000218960低表达组3年生存率显著高于lncRNA HIT000218960高表达组(P<0.05)。Cox回归显示,肿瘤组织中低分化、TNM分期Ⅲ期、淋巴结转移、lncRNA HIT000218960高表达、HMGA2 mRNA高表达是胃癌患者预后不良的危险因素(P<0.05)。结论:胃癌组织中存在lncRNA HIT000218960异常高表达,其与胃癌恶性进展及患者预后不良有关。  相似文献   
993.
《Palaeoworld》2023,32(3):442-457
In the Amellago area (central High Atlas), the widely distributed Toarcian succession consists of marls and marly limestones of the Tagoudite and Agoudim formations. We here describe, for the first time, the ammonites of the Polymorphum Zone from the Tagoudite Formation, including Canavaria cf. rosenbergi Fucini, C. aff. zancleana (Fucini), Dactylioceras (Eodactylites) mirabile (Fucini), D. (E.) aff. mirabile (Fucini), D. (E.) pseudocommune Fucini, D. (E.) simplex (Fucini), D. (Orthodactylites) aff. crosbeyi (Simpson), Lytoceras gr. villae Meneghini, Neolioceratoides cf. hoffmanni (Gemmellaro) and Praepolyplectus sp. This ammonite assemblage is closely correlated with those reported from the Polymorphum Zone of several basins of the Tethyan margins and the Northwest European Subboreal Realm, indicating marine communications between the different Moroccan Jurassic basins and the central Atlantic trough. The overlying Agoudim Formation yields ammonites of the Levisoni Zone in its base and rare ammonites of the Bifrons Zone in the middle part. Four significant changes in the ammonite assemblages during the early-middle Toarcian and their probable causes are also discussed.  相似文献   
994.
Malonate decarboxylase of Malonomonas rubra is a complex enzyme system involving cytoplasmic and membrane-bound components. One of these is a biotin-containing protein of Mr 120'000, the location of which in the cytoplasm was deduced from the following criteria: (i) If the cytoplasm was incubated with avidin and the malonate decarboxylase subsequently completed with the membrane fraction the decarboxylase activity was abolished. The corresponding incubation of the membrane with avidin, however, was without effect. (ii) Western blot analysis identified the single biotin-containing polypeptide of Mr 120'000 within the cytoplasm. (iii) Transmission electron micrographs of immuno-gold labeled M. rubra cells clearly showed the location of the biotinyl protein within the cytoplasm, whereas the same procedure with Propionigenium modestum cells indicated the location of the biotin enzyme methylmalonyl-CoA decarboxylase in the cell membrane. The biotin-containing protein of the M. rubra malonate decarboxylase enzyme system was not retained by monomeric avidin-Sepharose columns but could be isolated with this column in a catalytically inactive form in the presence of detergents. If the high binding affinity of tetrameric avidin towards biotin was reduced by destructing part of the tryptophan residues by irradiation or oxidation with periodate, the inhibition of malonate decarboxylase by the modified avidin was partially reversed with an excess of biotin. Attempts to purify the biotin protein in its catalytically active state using modified avidin columns were without success.  相似文献   
995.
寡糖的对氨基苯甲酸乙酯衍生物,以及它的全乙酰化产物具有紫外吸收基团适合HPLC分离,研究了氨基柱和十八烷基柱对寡糖混合物的分离性能及检测灵敏度。从免疫球蛋白M中分离到的寡糖组分,衍生后用HPLC进一步分离提纯出另一些含量较少的糖链。  相似文献   
996.
Many pseudomonads and other bacteria can grow on aliphatic and aromatic hydrocarbons that occur in the environment. We are examining the potential of such organisms as biocatalysts for the oxidation of a variety of substituted aliphatic and aromatic compounds. To attain a high production rate of oxidation products via such biotransformations, we have focused on two-liquid phase culture systems. In these systems, cells are grown in liquid media consisting of an aqueous phase containing water-soluble growth substrates and droplets of a water-immiscible organic solvent containing bioconversion substrates and products. For industrial applications of such two-liquid phase processes, several questions remain. What are the maximum rates at which apolar compounds can be transferred from the apolar phase to cells growing in the aqueous phase, i.e., what are the maximum space-time yields attainable in two-liquid phase fermentations under practical conditions? What does an efficient downstream processing of two-liquid phase medium involve? What safety regimes should be considered in working with flammable organic solvents? Can elevated pressure be used to increase oxygen transfer? Based on answers to these questions, we have recently developed a high-pressure, explosion-proof bioreactor system with Bioengineering AG (Wald, Switzerland), which will be installed in our pilot plant and used to explore two-liquid phase bioconversions at a pilot scale.  相似文献   
997.
We have isolated a Pseudomonas-like amylase producer, the strain MS300, which displayed a large halo on starch medium, from the deepest site of the Mariana Trench. The strain MS300 produced two major and two minor α-maltotetraohydrolases (G4-amylase). The two major G4-amylases share the same molecular weight of 55 000 but had different pI values, 5.0 and 4.7, respectively. The optimum temperature for activity of both major G4-amylases is 40°C, and the optimum pH is 6.8 for one and 8.9 for the other. MS300 produced more amylase under high hydrostatic pressure than under atmospheric pressure. Strain MS300 may be active in the deep sea at a depth of 10 897 m. Received: December 11, 1997 / Accepted: April 16, 1998  相似文献   
998.
Verapamil at 200 microM, prevented the respiratory stimulation, K+ loss, transmitter release, and 45Ca2+ entry into incubated synaptosomes evoked by veratrine (25 to 75 microM) or by high K+ (56 mM). Verapamil (100 microM) also blocked gamma-aminobutyric acid homoexchange, whilst tetrodotoxin was ineffective. Much lower concentrations of verapamil (less than 1 microM) blocked the 45Ca2+ entry caused by veratrine, but not its action in releasing neurotransmitter or K+. It is concluded that verapamil, at 30 to 200 microM, blocks active Na+ channels, thereby preventing depolarization. At greater than 1 microM, verapamil blocks Ca+ channels selectively.  相似文献   
999.
In our developed reverse phase high performance liquid chromatography, four forms of M125I-VIP have been isolated free from unlabled VIP and other iodinated components. The quicker eluting M125I-VIP forms (oxidised and reduced) have a consistently and significantly low non-specific binding with specific target cells of VIP (HT-29) as compared to the late eluting forms of VIP. The retention time is considerably increased when the molecule of VIP is fully iodinated.  相似文献   
1000.
Differential polarized phase fluorometry was used to quantify the rotational rate (R) and limiting anisotropy (r) of the membrane probe diphenylhexatriene (DPH) in solvents and lipid vesicles exposed to hydrostatic pressures ranging from 1 bar to 2 kbar. These measurements reveal the effect of pressure on the phase-transition temperatures of the phosphatidylcholine vesicles, and the effects of pressure on order parameter of the acyl side-chain region of the membranes, the latter as indicated by r. In addition to the well-known elevation of the transition temperature (Tc) with pressure, our results demonstrate that increased pressure restores the order of the bilayers to that representative of temperatures below the transition temperature. We also found that solvents which allowed free isotropic rotation of DPH at 1 bar no longer allowed free rotation when sufficiently compressed; moreover, the apparent DPH rotational rate increased with r. Pressure studies using both DPH and the charged DPH analogue, trimethylammonium DPH (TMA-DPH) indicated that the Tc of dipalmitoylphosphatidylcholine vesicles increased 23 K/kbar and an apparent volume change of 0.036 ml/mol lipid at the phase transition. Assuming, as has been proposed, that TMA-DPH is localized near the glycerol backbone region of the bilayers, these results indicate a similar temperature- and pressure-dependent phase transition in this region and the acyl side-chain region of the membrane.  相似文献   
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