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1.
Interrelations between host, bacterium and antibiotic compound in antibiotic therapy of bacterial infections are analysed. Some methods for the evaluation of antibacterial activity of antibiotics in vitro are described and their limits, in particular of the widely used MIC tests, are demonstrated. Data from trials comparing antibiotic applications once and twice a day as well as discussions in chemotherapy, concerning the applicability of in vitro results to therapy, are used to try to find practicable guidelines for the repetition of antibiotic therapy.  相似文献   
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Uterine inflammatory response is mediated by inflammatory mediators including eicosanoids and cytokines produced by immune and endometrial cells. Interactions between lipopolysaccharide (LPS) and cytokines, and leukotrienes (LTs) in endothelium, important for the host defence during the inflammation, are unknown. We studied the effect of LPS, tumour necrosis factor (TNF)‐α, interleukin (IL)‐1β, IL‐4 and IL‐10 on 5‐lipooxygenase (5‐LO), LTA4 hydrolase (LTAH) and LTC4 synthase (LTCS) mRNA and protein expression, LTB4 and LTC4 release from porcine endometrial endothelial cells, and cell viability. For 24 hr, cells were exposed to LPS (10 or 100 ng/ml of medium) and cytokines (each 1 or 10 ng/ml). 5‐LO mRNA/protein expression augmented after incubation with larger doses of LPS, TNF‐α, IL‐4 and IL‐10 and smaller dose of IL‐1β. Larger dose of TNF‐α, smaller doses of LPS and IL‐1β and both doses of IL‐10 increased LTAH mRNA/protein expression. LTAH protein content was up‐regulated by larger dose of LPS, but it was reduced in response to both doses of IL‐4. LTCS mRNA expression was elevated by larger doses of LPS, IL‐4 and IL‐10 or both doses of TNF‐α and IL‐1β. LTCS protein level increased after treatment with both doses of IL‐1β, IL‐4 and IL‐10, smaller dose of LPS and larger dose of TNF‐α. Both doses of LPS and larger doses of TNF‐α and IL‐10 increased LTB4 release. LPS, IL‐1β and IL‐10 at smaller doses, or TNF‐α and IL‐4 at larger doses stimulated LTC4 release. Smaller doses of TNF‐α and IL‐1β or both doses of IL‐4 enhanced the cell viability. This work provides new insight on the participation of LPS, TNF‐α, IL‐1β, IL‐4 and IL‐10 in LTB4 and LTC4 production/release from porcine endometrial endothelial cells, and the effect of above factors on these cells viability. The used cellular model gives the possibility to further establish the interactions between inflammatory mediators.  相似文献   
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Summary There were significant differences among pigeonpea [Cajanus cajan (L.) Millsp] Rhizobium sp. strains (IC 3506, IC 3484, IC 3195, and IC 3087) in their ability to nodulate and fix N2 under saline conditions. Pigeonpea plants inoculated with IC 3087 and IC 3506 were less affected in growth by salinity levels of 6 and 8 dS m-1 than plants inoculated with the other strains. For IC 3506, IC 3484, and IC 3195, there was a decrease in the number of nodules with increasing salinity, while the average nodule dry weight and the specific nitrogenase activity remained unaffected. However, in IC 3087, the number of nodules increased slightly with increasing salinity. Leaf-P concentrations increased with salinity in the inoculated plants irrespective of the Rhizobium sp. strain, and leaf-N concentrations decreased with increasing salinity in IC 3484 and IC 3195 only. Shoot-Na and-Cl levels were further increased in these salt-sensitive strains only at 8 dS m-1. Therefore there may be scope for selecting pigeonpea Rhizobium sp. symbioses better adapted to saline conditions. The Rhizobium sp. strains best able to form effective symbioses at high salinity levels are not necessarily derived from saline soils.Submitted as JA No. 919 by the International Crops Research Institute for the Semi-Arid Tropics (ICRISAT)  相似文献   
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Waterproof breathable layered fabrics allow water vapor passing through, but resist liquid water to pass. This ability of the fabrics to protect rain and snow water while allowing sweat vapor to evaporate from inside to outside atmosphere, leads them to be used as outdoor sportswear or protective clothing. The big challenge of enhanced hydrostatic resistance of these fabrics with proper breathability and thermal comfort has widened the research scope. This study presents an experimental investigation on hydrostatic resistance and thermal behavior of layered waterproof breathable fabrics. Six different types of hydrophobic and hydrophilic membrane laminated layered fabrics were evaluated by varying different fabric parameters in the experiment. Hydrostatic resistance and water vapor permeability of the laminated fabrics were measured by SDL ATLAS Hydrostatic Head Tester and PERMETEST respectively. Thermal properties were evaluated by ALAMBETA instrument. Moreover, FX-3300 air permeability tester was used to measure air permeability which represents the porosity of the fabrics and computer based See System software was used for water contact angle measurement on the outer fabric surface in order to determine the hydrophobic and hydrophilic properties. This experiment clearly discusses the influence of different fabric characteristics and parameters on hydrostatic resistance and thermal properties of the breathable laminated fabrics. The results show that fabric material composition, density, thickness, and hydrophobic and hydrophilic membranes have significant effects on hydrostatic resistance, breathability and thermal properties of different laminated fabrics.  相似文献   
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Specific contrast ultrasound is widely applied in diagnostic procedures on humans but remains underused in veterinary medicine. The objective of this study was to evaluate the use of microbubble-based contrast for rapid ultrasonographic diagnosis of thrombosis in small animals, using male New Zealand white rabbits (average weight about 3.5 kg) as a model. It was hypothesized that the use of microbubble-based contrast agents will result in a faster and more precise diagnosis in our model of thrombosis. A pro-coagulant environment had been previously established by combining endothelial denudation and external vessel wall damage. Visualization of thrombi was achieved by application of contrast microbubbles [sterically stabilized, phospholipid-based microbubbles filled with sulfur hexafluoride (SF6) gas] and ultrasonography. As a result, rapid and clear diagnosis of thrombi in aorta abdominalis was achieved within 10 to 30 s (mean: 17.3 s) by applying microbubbles as an ultrasound contrast medium. In the control group, diagnosis was not possible or took 90 to 180 s. Therefore, sterically stabilized microbubbles were found to be a suitable contrast agent for the rapid diagnosis of thrombi in an experimental model in rabbits. This contrast agent could be of practical importance in small animal practice for rapid diagnosis of thrombosis.  相似文献   
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Residues of the insect growth regulator diflubenzuron were quantified on horse chestnut (Aesculus hippocastanum L.) leaves treated with a diflubenzuron 480 g litre?1 SC, Dimilin. To analyse the samples, an analytical procedure was developed involving a simple extraction step followed by high‐performance liquid chromatography on an octadecyl‐modified silica column with methanol + 0.01 M ammonium acetate mobile phase. The results showed diflubenzuron to be highly stable on horse chestnut leaves; more than 4 months (127 days) after application, 38% (on average) of the insecticide still remained on/in the leaves. The data confirmed biological observations showing diflubenzuron's long‐term efficacy against the horse chestnut leafminer, Cameraria ohridella Deschka & Dimi?, which is the most important pest of the horse chestnut in Europe. The hypothesis of possible penetration of diflubenzuron into the leaf mass is explored and discussed. Copyright © 2006 Society of Chemical Industry  相似文献   
10.
Journal of Plant Diseases and Protection - The importance of herbal plants is evident in the prevalent use as flavoring ingredients in food. However, meeting the growing demand for organic grown...  相似文献   
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