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151.
Lasioglossins LLIII affect the morphogenesis of Candida albicans and reduces the duration of experimental vaginal candidiasis in mice
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Alena Vrablikova Lydie Czernekova Romana Cahlikova Zbynek Novy Milos Petrik Saima Imran Zdenek Novak Michal Krupka Vaclav Cerovsky Jaroslav Turanek Milan Raska 《Microbiology and immunology》2017,61(11):474-481
152.
In Pseudomonas fluorescens CHA0, mutation of the GacA-controlled aprA gene (encoding the major extracellular protease) or the gacA regulatory gene resulted in reduced biocontrol activity against the root-knot nematode Meloidogyne incognita during tomato and soybean infection. Culture supernatants of strain CHA0 inhibited egg hatching and induced mortality of M. incognita juveniles more strongly than did supernatants of aprA and gacA mutants, suggesting that AprA protease contributes to biocontrol. 相似文献
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154.
Troponin elevation is usually synonymous with acute coronary syndrome (ACS). Although sensitive for ACS, the elevation of serum troponin, in the absence of clinical evidence of ischemia, should prompt a search for other etiologies of myocardial necrosis. In fact, elevated values of troponin are correlated with myocardial necrosis even though it does not discriminate the mechanism involved. We report a series of seven patients (age range 18-67 years), who presented with complaints of chest discomfort and were found to have regular supraventricular tachycardia (5 patients) and one patient each with atrial fibrillation and ventricular tachycardia. All these patients had elevated troponin I and underwent coronary angiography that revealed normal epicardial coronary arteries. This is first case series in which all patients underwent coronary angiography and none of the patients was hemodynamically unstable at the time of presentation. Patients with elevated troponin due to conditions other than ACS can receive inappropriate and delayed definitive diagnosis and treatment. 相似文献
155.
A. Incarbona S. Bonomo E. Di Stefano S. Zgozi N. Essarbout M. Talha G. Tranchida A. Bonanno B. Patti F. Placenti G. Buscaino A. Cuttitta G. Basilone T. Bahri F. Massa P. Censi S. Mazzola 《Marine Micropaleontology》2008,67(3-4):297-309
Quantitative analysis of 67 calcareous nannofossil assemblages from surface sediments recovered in a wide area across the Sicily Channel has been carried out in order to improve the interpretation of palaeontological data based on this planktonic group in a key area for Mediterranean palaeoceanographic studies. The investigation focused on three case studies that demonstrate the high potentiality of such a combined approach, taking into account the recent distribution of taxa or groups of taxa on the sea floor and the palaeontological record. The distribution of reworked specimens over the northern Sicily Channel sea floor validates the role of southern Sicily as a source region for reworked nannofossils and the role of rivers as their carrier. Eustatic sea-level fluctuations can be considered to be the main factor that influenced the abundance variations in sedimentary sequences of this area. The distribution of Florisphaera profunda can be explained in terms of topography (positive correlation) and mesoscale oceanographic circulation. In particular, its significant anti-correlation to the amount of chlorophyll-A deduced by satellite imagery validates the use of this species as a proxy for palaeoproductivity reconstructions. Finally, high abundance values of G. oceanica are confined to the westernmost part of the Sicily Channel, coinciding with a water mass salinity minimum. In particular, abundances of up to about 10% were observed in the westernmost part of the African Margin, suggesting the importance of the Atlantic Tunisian Current, whose activity is more pronounced in winter. The comparison of data of this species between 135 and 110 kyr BP, inside and outside the Channel, led us to deduce that the physical transport in almost unmodified waters of Atlantic origin might be the most important factor for its significant occurrence. 相似文献
156.
杨树根系浸提液对3种牧草种子萌发及幼苗生长的影响 总被引:4,自引:0,他引:4
采用不同浓度(3、10和30mg/mL)的南林95杨〔PopulusdeltoidsBartr.cv.Lux×P.euramericana(Dode)Guineircv.I 45/51〕和NL 80351杨(P.deltoidsBartr.cv.Lux×P.deltoidsBartr.cv.Harvard)根系浸提液,处理杨树 牧草复合经营系统中3种主要牧草种子,探讨杨树根系浸提液对牧草种子萌发及幼苗生长的影响。结果表明:南林95杨和NL 80351杨根系浸提液对3种牧草种子的萌发及幼苗的生长有一定影响。这2个无性系根系浸提液对紫花苜蓿(MedicagosativaL.)、白三叶(TrifoliumrepensL.)和杂交狼尾草(PennisetumalopecuroidesL.×P.americanumL.)的种子发芽率、幼苗高生长、根长生长及种子活力主要表现为抑制作用,在浓度较高时影响尤为明显;但2个无性系根系浸提液对白三叶的高生长(南林95杨30mg/mL除外)表现出一定的促进作用;在3mg/mL浓度时,2个无性系根系浸提液对白三叶的种子活力也有一定的促进作用。 相似文献
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158.
癌胚抗原(CEA)启动子在肿瘤细胞中的特异表达及介异bak基因诱发凋亡 总被引:1,自引:0,他引:1
构建由癌胚抗原 (CEA)启动子控制报道基因增强型绿色荧光蛋白 (EGFP)表达的重组表达质粒pCEA EGFP .用转染细胞后检测荧光的方法对CEA阳性细胞进行简便、直观的检测 ,并结合流式细胞计数对CEA启动子在人结直肠腺癌细胞LS 1 74T、结肠癌细胞SW 4 80、肺腺癌细胞A5 49、人宫颈癌细胞HeLa和人喉癌细胞HEp 2中的活性进行了分析 ,发现其在SW4 80、LS 1 74T、A5 49中活性较强 ,而在HeLa和HEp 2中无活性 .构建由CEA启动子控制凋亡基因bak表达的重组表达质粒pCEA bak ,转染HeLa及SW 4 80细胞 ,用Hoechst332 5 8染色及PI染色 流式细胞计数分析的方法证明 ,pCEA bak转染能够特异性引起SW 4 80细胞的凋亡 .结果表明 ,CEA启动子具有很好的特异性 ,CEA介导bak基因的方法可望用于CEA阳性癌细胞的靶向性基因治疗 . 相似文献
159.
Background and Aims
When root-zone O2 deficiency occurs together with salinity, regulation of shoot ion concentrations is compromised even more than under salinity alone. Tolerance was evaluated amongst 34 accessions of Hordeum marinum, a wild species in the Triticeae, to combined salinity and root-zone O2 deficiency. Interest in H. marinum arises from the potential to use it as a donor for abiotic stress tolerance into wheat.Methods
Two batches of 17 H. marinum accessions, from (1) the Nordic Gene Bank and (2) the wheat belt of Western Australia, were exposed to 0·2 or 200 mol m−3 NaCl in aerated or stagnant nutrient solution for 28–29 d. Wheat (Triticum aestivum) was included as a sensitive check species. Growth, root porosity, root radial O2 loss (ROL) and leaf ion (Na+, K+, Cl−) concentrations were determined.Key Results
Owing to space constraints, this report is focused mainly on the accessions from the Nordic Gene Bank. The 17 accessions varied in tolerance; relative growth rate was reduced by 2–38 % in stagnant solution, by 8–42 % in saline solution (aerated) and by 39–71 % in stagnant plus saline treatment. When in stagnant solution, porosity of adventitious roots was 24–33 %; salinity decreased the root porosity in some accessions, but had no effect in others. Roots grown in stagnant solution formed a barrier to ROL, but variation existed amongst accessions in apparent barrier ‘strength’. Leaf Na+ concentration was 142–692 µmol g−1 d. wt for plants in saline solution (aerated), and only increased to 247–748 µmol g−1 d. wt in the stagnant plus saline treatment. Leaf Cl− also showed only small effects of stagnant plus saline treatment, compared with saline alone. In comparison with H. marinum, wheat was more adversely affected by each stress alone, and particularly when combined; growth reductions were greater, adventitious root porosity was 21 %, it lacked a barrier to ROL, leaf K+ declined to lower levels, and leaf Na+ and Cl− concentrations were 3·1–9-fold and 2·8–6-fold higher, respectively, in wheat.Conclusions
Stagnant treatment plus salinity reduced growth more than salinity alone, or stagnant alone, but some accessions of H. marinum were still relatively tolerant of these combined stresses, maintaining Na+ and Cl− ‘exclusion’ even in an O2-deficient, saline rooting medium.Key words: Aerenchyma, combined salinity and waterlogging, leaf Cl−, leaf K+, leaf Na+, radial O2 loss, salt tolerance, salinity–waterlogging interaction, sea barleygrass, waterlogging tolerance, wheat, wild Triticeae 相似文献160.
This paper presents the development of an integrated simulation-clustering-optimization (ISCO) approach for supporting the groundwater bioremediation design. To investigate remediation performances, a subsurface model was employed to simulate contaminant transport. A mixed integer nonlinear optimization model was formulated to evaluate different remediation strategies. Multivariate relationships based on stepwise clustering analysis were developed to facilitate the incorporation of a simulation model within a nonlinear optimization framework. Based on the developed statistical relationships, a prediction system was constructed to provide all possible outputs for the proposed remediation design. By using the prediction system, the optimal strategy to achieve the remediation objective can be directly located. The proposed ISCO approach can improve bioremediation designs by providing adjustable schedules for operating wells from stage to stage, which will make the optimization more realistic. This approach was examined through the pilot-scale study of a western Canadian site. The optimization results demonstrated that 31% of the cost can be reduced by using a multi-stage design to achieve the same remediation objective as that of a single-stage design. 相似文献