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Plant nutrition management is known as an efficient strategy to control environmental constraints. This experiment was conducted in a climate control greenhouse with a hydroponic system. The high temperature (36 °C?±?1) was imposed on the pots after fruit formation. The studied factors were silicon in 2 concentrations (0 and 4 parts per thousand (ppt)) and salicylic acid in 3 concentrations (0, 0.5, and 1 mM). They were sprayed on cucumber plants 3 times and under high-temperature conditions to evaluate if they can regulate and improve the yield and quality of cucumber fruit under high-temperature conditions or not. The results showed that all treatments significantly improved the nutritional status, total yield, and fruit quality (including marketable yield (i.e., fruits that can be sold due to their good shape) and nitrate content). Under high-temperature conditions, foliar application of silicon had the highest effect on the increase of total yield and marketable fruit yield (respectively, 36.14% and 40.29% increase compared to the control treatment). Micro-nutrients concentrations in the leaf were significantly increased by Si but a reverse status happened for salicylic acid. Under high temperatures, both treatments also significantly decreased the nitrate content of the fresh matter of fruit but silicon was the superior treatment. Silicon and salicylic acid, respectively, had positive effects on mitigation of adverse effects of high temperature on cucumber plants. These findings suggest the use of these treatments under high-temperature conditions in greenhouse cucumber production.

Graphical Abstract

N–No3 content in dry matter of leaf (left) and fresh matter of fruit (right) affected by different treatments. *SaA0–SiA4: 4 ppt Si; SaA0.5–SiA0: 0.5 mM SA; SaA0.5–SiA4: 0.5 mM SA?+?4 ppt Si; SaA1–SiA0: 1 mM SA; SaA1–SiA4: 1 mM SA?+?4 ppt Si; control: without any SA and Si applications. Means in the same column followed by the same letter are not significantly different according to DMRT at (P?≤?0.05)

  相似文献   
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Mitochondrial DNA (mtDNA) from cell suspension cultures of two intergeneric somatic hybrids of Pennisetum americanum (pearl millet) + Saccharum officinarum (sugarcane) was examined by restriction endonuclease digestion and hybridization with sorghum mtDNA cosmids. The mtDNA of one somatic hybrid was indistinguishable from that of pearl millet, while the second exhibited a combination of parental mtDNAs, suggesting mitochondrial fusion. Several novel, possibly recombinant, mtDNA restriction fragments were detected in this hybrid, which may have resulted from intergenmic recombination.Florida Agriculture Experiment Station Journal Series No: 8090.  相似文献   
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Summary A rapid procedure for introducing foreign genes inLotus corniculatus based on the induction of hairy roots byAgrobacterium rhizogenes was developed. Expression of chloramphenicol acetyltransferase and neomycin phosphotransferase II was revealed in transgenic plants. Southern blot hybridization was used to confirm the genetic transformation. The transgenic plants looked normal and did not show any morphological modification compared to the seed grown plants.  相似文献   
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Thirty postmenopausal women (11 omnivores, 10 vegetarians and 9 apparently healthy women with surgically removed breast cancer) were investigated with regard to the association of their urinary excretion of estrogens, lignans and isoflavonoids (all diphenols) with plasma sex hormone binding globulin (SHBG). A statistically significant positive correlation between urinary total diphenol excretion and plasma SHBG was found which remained statistically significant after elimination of the confounding effect of body mass determined by body mass index (BMI). Furthermore we found a statistically significant negative correlation between plasma SHBG and urinary excretion of 16α-hydroxyestrone and estriol which also remained significant after eliminating the effect of BMI. Furthermore we observed that enterolactone (Enl) stimulates the synthesis of SHBG by HepG2 liver cancer cells in culture acting synergistically with estradiol and at physiological concentrations. Enl was rapidly conjugated by the liver cells, mainly to its monosulfate. Several lignans and the isoflavonoids daidzein and equol were found to compete with estradiol for binding to the rat uterine type II estrogen binding site (the s.c. bioflavonoid receptor). It is suggested that lignans and isoflavonoids may affect uptake and metabolism of sex hormones by participating in the regulation of plasma SHBG levels and in this way influence their biological activity and that they may inhibit cancer cell growth like some flavonoids by competing with estradiol for the type II estrogen binding sites.  相似文献   
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Summary Leaf disc transformation-regeneration technique was applied to the drought tolerant wild relative of cultivated tomato,Lycopersicon chilense, using a plasmid construct which contained the coding sequences of neomycin phosphotransferase (NPTII) and chloramphenicol acetyltransferase (CAT) genes. The two genotypes used, LA2747 and LA1930, showed a distinct difference in their aptitude to transformation; a higher success rate was obtained for the first genotype in every stage of the process. Shoots were formed on the regeneration medium containing 100 g/ml kanamycin through direct or indirect organogenesis. Root formation became only possible when the concentration of kanamycin was reduced to 50 g/ml. Expression of chloramphenicol acetyltransferase gene was observed in all of the kanamycin-screened plants after they matured; the activity of the gene was absent or low in some of the young plants. The presence of the CAT gene in transgenic plants was further confirmed by Southern blot analysis. Although transgenic plants grew to maturity, they did not produce fruit, owing to the self incompatibility ofL. chilense. Abbreviations BAP 6-benzylaminopurine - CAT chloramphenicol acetyltransferase - 2,4-D 2,4-dichlorophenoxyacetic acid - IAA indole-3-acetic acid - LB Luria Broth - EDTA ethylenediamine-tetraacetic acid  相似文献   
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International Journal of Peptide Research and Therapeutics - LL-37 is a 37 amino acid long cationic peptide belonging to the cathelicidin family of antimicrobial peptides. Limited investigations...  相似文献   
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The relationship between serum anti-heat shock protein (Hsp)27 antibody and high sensitive C-reactive protein (hs-CRP) levels and indices of cardiac function were investigated in patients undergoing coronary artery bypass grafting (CABG) or heart valve replacement. The changes in anti-Hsp27 antibody titers and hs-CRP levels were compared among patients undergoing off-pump and on-pump CABG or valvular heart replacement. Fifty-three patients underwent off-pump, on-pump CABG, and heart valvular replacement in each group. Serum anti-Hsp27 titers and hs-CRP values were measured 24 h before and after the operation and at discharge. Echocardiography was performed before surgery and before discharge. The results were compared with values from 83 healthy controls. hs-CRP levels increased and anti-Hsp27 antibody decreased following surgery (P < 0.001 and P < 0.05, respectively), although these changes were independent of operative procedure (P = 0.361 and P = 0.120, respectively). Anti-Hsp27 antibody levels were higher at the time of discharge (P = 0.016). Only in coronary patients were anti-Hsp27 antibody levels negatively associated with E/E′ (r = −0.268, P = 0.022), a marker of pulmonary capillary wedge pressure. In conclusions, anti-Hsp27 antibody levels are associated with indices of cardiac function in coronary patients. Cardiopulmonary bypass had no significant effect on the induction of changes in anti-Hsp27 levels. Moreover, anti-Hsp27 antibody levels fell in all groups postoperatively; this may be due to the formation of immune complexes of antigen–antibody, and antibody levels were higher at the time of discharge.

Electronic supplementary material

The online version of this article (doi:10.1007/s12192-012-0358-y) contains supplementary material, which is available to authorized users.  相似文献   
10.
Firefly bioluminescence reaction in the presence of Mg2 +, ATP and molecular oxygen is carried out by luciferase. The luciferase structure alterations or modifications of assay conditions determine the bioluminescence color of firefly luciferase. Among different beetle luciferases, Phrixothrix hirtus railroad worm emits either yellow or red bioluminescence color. Sequence alignment analysis shows that the red-emitter luciferase from Phrixothrix hirtus has an additional arginine residue at 353 that is absent in other firefly luciferases. It was reported that insertion of Arg in an important flexible loop350–359 showed changes in bioluminescence color from green to red and the optimum temperature activity was also increased. To explain the color tuning mechanism of firefly luciferase, the structure of native and a mutant (E354R/356R/H431Y) of Lampyris turkestanicus luciferase is determined at 2.7 Å and 2.2 Å resolutions, respectively. The comparison of structure of both types of Lampyris turkestanicus luciferases reveals that the conformation of this flexible loop is significantly changed by addition of two Arg in this region. Moreover, its surface accessibility is affected considerably and some ionic bonds are made by addition of two positive charge residues. Furthermore, we noticed that the hydrogen bonding pattern of His431 with the flexible loop is changed by replacing this residue with Tyr at this position. Juxtaposition of a flexible loop (residues 351–359) in firefly luciferase and corresponding ionic and hydrogen bonds are essential for color emission.  相似文献   
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