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511.
Effects of juglone on seedling growth of cucumber (Cucumis sativus cv. Beith Alpha) with respect to physiological and anatomical parameters were investigated. Growth parameters (seedling elongation, fresh and dry weights) were reduced by 1 mM juglone. Juglone also decreased chlorophyll a and b contents and reduced some anatomical tissues (xylem vessel and bundle radius of stem, stomata length and stomata number of the cotyledons). The anatomical changes in stem and cotyledon of the seedlings were related to growth inhibiting effect of juglone. On the other hand, increase in catecholase and tyrosinase activities by the effect of juglone were also recorded.  相似文献   
512.
Artemisia annua L. (Asteraceae Family) is an important plant in Asia that has been used for treating different diseases, including fever due to malaria, wounds, tubercolisis, scabues, pain, convulsions, diabetes, and inflammation. In this study we aimed to evaluate the effects of different polarity extracts (hexane, dichloromethane, ethyl acetate, ethanol, ethanol/water (70 %) and water) from A. annua against the burden of inflammation and oxidative stress occurring in colon tissue exposed to LPS. In parallel, chemical composition, antiradical, and enzyme inhibition effects against α-amylase, α-glucosidase, tyrosinase, and cholinesterases were evaluated. The water extract contained the highest content of the total phenolic with 34.59 mg gallic acid equivalent (GAE)/g extract, while the hexane had the highest content of the total flavonoid (20.06 mg rutin equivalent (RE)/g extract). In antioxidant assays, the polar extracts (ethanol, ethanol/water and water) exhibited stronger radical scavenging and reducing power abilities when compared to non-polar extracts. The hexane extract showed the best AChE, tyrosinase and glucosidase inhibitory effects. All extracts revealed effective anti-inflammatory agents, as demonstrated by the blunting effects on COX-2 and TNFα gene expression. These effects seemed to be not related to the only phenolic content. However, it is worthy of interest to highlight how the higher potency against LPS-induced gene expression was shown by the water extract ; thus suggesting a potential phytotherapy application in the management of clinical symptoms related to inflammatory colon diseases, although future in vivo studies are needed to confirm such in vitro and ex vivo observations.  相似文献   
513.
The administration separately and sequentially of carbenicillin and gentamicin eradicated Ps. aeruginosa infections, during the period over which they were given, in all of 25 critically ill patients. Electron microscopy revealed differences in the action of these two antibiotics against Ps. aeruginosa in vitro. Culture studies showed synergism between them and destruction by gentamicin of the carbenicillin-induced long, filamentous form of the organism.  相似文献   
514.
Due to a long-lasting increase in global trade, only interrupted by the late-2000s economic crisis, container traffic has grown dramatically. As a result, new terminals have opened and existing terminals face much higher container handling than before. In order to meet these challenges, one of the biggest container terminals in Turkey has begun to reconsider its terminal operations and to achieve improvements of its overall logistics performance. Because the factors impacting the terminal’s performance are highly interrelated, a simulation model was developed to analyze the terminal operations, to identify potential bottleneck resources and to highlight directions for the future development of the configuration and the operational control system. For a long-established terminal like the one considered in this study the options for improving the overall performance are limited by the geographical dimensions and by the existing terminal equipment. By use of the simulation model the terminal operations are evaluated under different workload scenarios and alternative configurations are tested in order to support strategic decisions on the terminal’s development.  相似文献   
515.
Predictions of added resistance and the effective power of ships were made for varying barnacle fouling conditions. A series of towing tests was carried out using flat plates covered with artificial barnacles. The tests were designed to allow the examination of the effects of barnacle height and percentage coverage on the resistance and effective power of ships. The drag coefficients and roughness function values were evaluated for the flat plates. The roughness effects of the fouling conditions on the ships’ frictional resistances were predicted. Added resistance diagrams were then plotted using these predictions, and powering penalties for these ships were calculated using the diagrams generated. The results indicate that the effect of barnacle size is significant, since a 10% coverage of barnacles each 5 mm in height caused a similar level of added power requirements to a 50% coverage of barnacles each 1.25 mm in height.  相似文献   
516.
We present a novel computational model that detects temporal configurations of a given human neuronal pathway and constructs its artificial replication. This poses a great challenge since direct recordings from individual neurons are impossible in the human central nervous system and therefore the underlying neuronal pathway has to be considered as a black box. For tackling this challenge, we used a branch of complex systems modeling called artificial self-organization in which large sets of software entities interacting locally give rise to bottom-up collective behaviors. The result is an emergent model where each software entity represents an integrate-and-fire neuron. We then applied the model to the reflex responses of single motor units obtained from conscious human subjects. Experimental results show that the model recovers functionality of real human neuronal pathways by comparing it to appropriate surrogate data. What makes the model promising is the fact that, to the best of our knowledge, it is the first realistic model to self-wire an artificial neuronal network by efficiently combining neuroscience with artificial self-organization. Although there is no evidence yet of the model’s connectivity mapping onto the human connectivity, we anticipate this model will help neuroscientists to learn much more about human neuronal networks, and could also be used for predicting hypotheses to lead future experiments.  相似文献   
517.
518.
Sunitinib is a multitargeted kinase inhibitor that inhibits many receptor tyrosine kinases and has been used in the treatment of gastrointestinal stromal tumors, metastatic renal cell carcinoma, and pancreatic neuroendocrine tumors. In this study, the effects of sunitinib given to rats, both alone and after stress with cisplatin, were investigated. The animals were divided into four groups – (1) control group (C) administered interperitoneally with a single dose 0.9 % saline, (2) Cis group administered a single dose (7 mg/kg) of cisplatin, (3) Sun group administered 10 mg/kg sunitinib for seven days, and (4) Cis+Sun group administered 10 mg/kg sunitinib for seven days after a single dose (7 mg/kg) of cisplatin. After these applications, the rats were sacrificed, and blood and tissue samples were taken for biochemical and histopathological evaluations. Sunitinib did not show any effect on urea, creatine, and kidney IL1β and TGF-β3 expression levels when administered alone; it increased ALT, AST, and IL-38 levels. When sunitinib was given to the cisplatin-induced rats, it was observed that the increase in ALT, AST, and IL-38 levels increased more than the rats that was given only sunitinib. According to the data obtained, sunitinib does not cause a significant change in kidney tissue under both normal and stress conditions, while it creates stress in liver tissue. In addition, its toxicity in the liver becomes more certain as a result of its combination with cisplatin.  相似文献   
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