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Prostacyclin infused intravenously in human volunteers induces ex vivo inhibition of platelet aggregation, tachycardia and hypotension. The inhibition of platelet aggregation is obtained with slightly lower doses than those which exhibit cardiovascular effects.The cardiovascular effects disappeared within a few minutes after discontinuing the infusion of prostacyclin but the platelet effects were longer lasting.Prostacyclin did not have any effect on platelet count, platelet factor 3, accelerated partial thromboplastin time, prothrombin time, euglobulin clot lysis time, fibrinogen degradation products, blood glucose concentration or urine sodium potassium ratio.  相似文献   
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Plant growth promoting rhizobacteria were isolated and characterized from sandy soils in Pakistan. The role of the rhizobacteria, in association with plant growth regulators, was studied on the roots of wheat grown under water stressed conditions. The plant growth promoting rhizobacteria were characterized on the basis of colony morphology, biochemical traits and identified on the basis of 16S-rRNA gene sequencing which identified the selected isolates Planomicrobium chinense, Bacillus cereus and Pseudomonas fluorescens. Antibacterial and antifungal activities were determined. The fresh cultures (24 h old) of isolates were used to soak the seeds for 2–3 h prior to sowing. The growth regulators salicylic acid and putrescine were applied to the plant as foliar spray at three leaf stage. The plant growth promoting rhizobacteria produced exopolysaccharides that formed soil aggregation around roots of the plants and significantly enhanced water holding capacity of sandy soil. The relative water content (80%) of leaves and root fresh (80%) and dry weight (68%) were higher in plant growth promoting rhizobacteria inoculated plants. The nutrient content of rhizosphere soil of treated plants was also enhanced (Ca 35%, K 34%, Mg 52% and Na 42%) over stressed controls. Integrative use of effective plant growth promoting rhizobacteria in combination with salicylic acid appears to be an effective eco-friendly approach to increase drought tolerance in wheat plants to combat desertification.  相似文献   
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Background  

Rapid, robust and reversible induction of transgene expression would significantly facilitate cancer gene therapy as well as allow the in vivo functional study of newly discovered genes in tumor formation and progression. The popularity of the ecdysone inducible gene switch system has led us to investigate whether such a system can successfully regulate gene expression in a syngeneic tumor system in vivo.  相似文献   
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Numerous studies have shown that the estrogen receptor beta (ERβ) and interleukin 6 receptor (IL-6R) had interaction in many tumors, including lung cancer. Previous studies found that ERβ5 exhibits a different biological function compared with the other subtypes of ERβ. Therefore, this study mainly explores the interaction between ERβ5 and IL-6R in the progression of lung cancer. We found that the expression of ERβ5, IL-6 and glycoprotein 130 (GP130) were significantly increased (P < 0.001) and the 5-year survival rate with the co-expression of ERβ5 and GP130 is significantly lower (P = 0.0315) in non-small cell lung cancer (NSCLC) patients. The cell proliferation, invasion, and cell cycle were markedly increased, and the cell apoptotic was markedly inhibited with the concurrent action of ERβ5 and IL-6 in A549 cells (P < 0.05). In addition, the expression of ERβ5, GP130, p-AKT, and p-44/42 MAPK was also significantly increased in A549 cells (P < 0.05). These results indicate that ERβ5 and GP130 can synergistically promote the progression of NSCLC and maybe combined as an independent prognostic factor in patients. In addition, these results also provide a theoretical basis for the combined targeting therapy of ERβ5 and GP130 in NSCLC.  相似文献   
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Chaperonesare an essential component of a cell's ability to respond to environmental challenges. Chaperones have been studied primarily in bacteria, but in recent years it has become apparent that some classes of chaperones either are very divergent in bacteria relative to archaea and eukaryotes or are missing entirely. In contrast, a high degree of similarity was found between the chaperonins of archaea and those of the eukaryotic cytosol, which has led to the establishment of archaeal model systems. The archaeon most extensively used for such studies is Thermoplasma acidophilum, which thrives at 59 degrees C and pH 2. Here we review information on its chaperone complement in light of the recently determined genome sequence.  相似文献   
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