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An antiarrhythmic action of water-soluble antioxidant SD-6 from 3-hydroxypyridine class and its effect on the transmembrane potentials were studied using the isolated rat heart and papillary muscle. Ischemia was induced by the occlusion of the left anterior descending coronary artery. 10 minutes later the ligation was removed and reperfusion was achieved. In the control, ischemia induced premature ventricular complexes, tachycardia and, in some cases, fibrillation. During perfusion total fibrillation occurred in 100% of the experiments. SD-6 in the doses of 10(-6) g/ml and 5 X 10(-6) g/ml significantly reduced the incidence of fibrillation and tachycardia. In the experiments on the papillary muscle SD-6 during reperfusion completely normalized the action potential duration and removed depolarization developed in hypoxia, which suggests the ability of the antioxidant to block reperfusion-induced arrhythmias by normalization of the parameters of electrical heterogeneity. These data show that the origin of reperfusion-induced arrhythmias is connected with the activation of free radical metabolites and that their scavengers--synthetic antioxidants from 3-hydroxypyridine class--can be used as new antiarrhythmic agents. 相似文献
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Abstract The effects of gibberellic acid (GA3) on whole sunflower (Helianthus annuus L.) plants grown at three potassium (K) levels (0.0, 0.5 and 5.0 mM) were studied. A tenfold increase in the length of the first internode was observed when plants grown without K were treated with GA3. The uneven K distribution along the plant (higher K content in the higher internodes) was enhanced by GA3 treatment. Gibberellic acid increased the content of reducing sugars, especially in K-deficient plants. An increase in the K level in the nutrient solution resulted in a decrease of the osmotic potential of stem segments. Osmotic potential differences within the elongating first internode were increased by GA3 treatment. 相似文献
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MILAN CHVÁLA 《Systematic Entomology》1996,21(4):265-294
Abstract. The European species of the Hilara maura-group are revised. Three species are described as new to science, namely, H.nitidorella sp.n., H.discalis sp.n. (both temperate Central and Western Europe) and H.mauroides sp.n. (Caucasus, male only). A further five species, H.hybrida Collin, H.femorella Zetterstedt, H.sulcitarsis Strobl, H.tyrolensis Strobl and H.bartaki Straka are redescribed, and H.eumera Loew, 1873 becomes a new synonym of H.nitidula Zetterstedt, 1838. Seven lectotypes are designated. All IS European species are keyed, the main differential characters are illustrated, and additional data on biology and distribution are given. The Hilara maura-group is recognized as a monophyletic group within the genus, characterized by a set of apomorphous characters, and the hypothetical phylogenetic relationships of the species, classified into four natural complexes, are demonstrated. 相似文献
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FOUAD SAYAH CLAIRE FAYET ANNE-MARIE LA VERDURE 《Invertebrate reproduction & development.》2013,57(2-3):269-275
Summary A polyclonal antibody raised against allatostatin-3 of Blattella germanica (BLAST-3) has been used to immunolocalize allatostatin-like peptides in the brain-retrocerebral complex of Labidura riparia adult females. Strongly stained immunoreactive cells are observed in the pars intercerebralis (14 cells) and mainly in the pars lateralis (32 cells). Fibres leading to the corpus allatum are also stained. In the deutocerebrum, one cell is immunostained at the root of each antennal nerve. In the tritocerebmm two cells in each brain hemisphere are weakly immunostained. During the reproductive cycle, these cells and their axons show immunoreactivity at previtellogenic, ovulation and ovarian arrest periods. During vitellogenesis, immunoreactivity is restricted to only four perikarya in the pars intercerebralis. When young vitellogenic females are injected with 20-hydroxyecdysone (20E), which inhibits vitellogenesis, full immunoreactivity reappears, suggesting sensibility of these cells to 20E as is expected for a negative feed-back loop (Sayah et al., 1995). These results show that BLAST-3-like material is produced periodically in Labidura in correlation with low levels of juvenile hormone and the absence of vitellogenesis. This study contributes to provide information on the degree of homology of allatostatins across various insects. 相似文献
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探究细菌性阴道炎(BV)合并人乳头瘤病毒16(HPV16)感染患者阴道菌群分布与局部免疫的关系。
选取2019年1月到2023年1月我院收治的83例BV合并HPV16感染患者和81例单纯BV患者,分别作为研究组和对照组,检测两组患者阴道菌群分布和宫颈阴道分泌物中T淋巴细胞亚群(CD4+、CD8+、CD4+/CD8+)和炎症因子(IL-1β、IFN-γ、IL-2)水平。
研究组乳酸杆菌数量低于对照组,加德纳菌、大肠埃希菌、无乳链球菌、金黄色葡萄球菌、铜绿假单胞菌、白假丝酵母菌数量高于对照组(
合并HPV16感染可使BV患者阴道乳酸杆菌数量减少,阴道微生态失衡,局部免疫功能下降,应尽早检测此类患者阴道菌群和宫颈阴道局部免疫情况,进行针对性干预。
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LA BARRE J 《Journal de physiologie》1956,48(3):588-590