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The effect of the type I interferon on the development and process of experimental pyelonephritis caused by E. coli was studied on mice weighing 12 to 14 g. Interferon was administered intraperitoneally in a dose of 1000 units on days 3 and 7 of the disease. It was shown that the administration of the type I interferon to the mice with experimental pyelonephritis promoted rapid elimination of bacteria from the kidneys, prevented their penetration to the contralateral (intact) kidney, prevented marked macro- and microscopic damages in the kidneys, lowered the intensity of the inflammatory reaction, and increased the phagocytic activity of neutrophils and the number of the E-rosette-forming lymphocytes in the thymus. The data provided experimental grounding for clinical trials of interferon preparations in treatment of bacterial pyelonephritis.  相似文献   
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Antibiotic salvin obtained from Salvia officinalis has been studied for its effect on the growth and ultrastructure of Staphylococcus aureus 209P. The antibiotic in the sub-bacteriostatic concentration considerably elongates the lag-phase (up to 11-12 h) exerting no significant effect on the growth rate of the staphylococcus population as well as it prolongs duration of the exponential phase. The analysis of electronograms of staphylococcus cells subjected to the action of salvin in the concentrations similar to the minimal inhibitory concentration (MIC), has revealed the cell thinning, inhibition and destruction of the division. The introduction of 5MIC antibiotic into the exponentially grown culture made a cell wall considerably thinner, destructing its external layer; the number of lyzed cells sharply increased. The appearance of bodies not described previously with a membrane envelope and ribosomes as well as of mesosomal structures was observed.  相似文献   
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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   
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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   
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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   
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Striped hamsters (Cricetulus barabensis sensu lato) represent a complex of chromosomally distinct allopatric lineages/taxa of either species or subspecies rank. They are widely distributed across the steppes of eastern and central Palearctic. Phylogenetic analysis of cytochrome b gene sequences based on 496 specimens from 112 localities revealed five well‐supported lineages divergent at 2%–4%. Two of them correspond to “griseus” (2n = 22) and “pseudogriseus” (2n = 24) karyomorphs and are placed as sister taxa. The “barabensis” (2n = 20) karyomorph is represented by three other branches and appears non‐monophyletic. All mtDNA lineages are distributed allopatrically or parapatrically; no indications of gene flow between populations of different chromosomal races were found. The results of the molecular clock analysis suggest that the main lineages diverged in the late Middle Pleistocene. The inferred evolutionary scenario implies that the common ancestor of the recent lineages belonged to the 2n = 20 karyomorph and originated in the eastern part of the contemporary range.  相似文献   
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Polar auxin transport plays a divergent role in plant growth and developmental processes including root and embryo development, vascular pattern formation and cell elongation. Recently isolated Arabidopsis pin gene family was believed to encode a component of auxin efflux carrier (G(?)lweiler et al, 1998). Based on the Arabidopsis pin1 sequence we have isolated a Brassica juncea cDNA (designated Bjpin1), which encoded a 70-kDa putative auxin efflux carrier. Deduced BjPIN1 shared 65% identities at protein level with AtPINl and was highly homologous to other putative PIN proteins of Arabidopsis (with highest homology to AtPIN3). Hydrophobic analysis showed similar structures between BjPINl and AtPIN proteins. Presence of 6 exons (varying in size between 65 bp and 1229 bp) and 5 introns (sizes between 89 bp and 463 bp) in the genomic fragment was revealed by comparing the genomic and cDNA sequences. Northern blot analysis indicated that Bjpin1 was expressed in most of the tissues tested, with a relatively h  相似文献   
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