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101.
102.
We describe three new species of the genus Peptostreptococcus which were isolated from human specimens and were tentatively identified as Peptostreptococcus prevotii. These three organisms were not homologous with previously described type strains of the genus Peptostreptococcus. A total of 12 strains that were identified biochemically as P. prevotii were divided into five independent DNA similarity groups; 10 of these strains were divided into three similarity groups which exhibited significant phenotypic differences from previously described species. Therefore, we propose the following new species: Peptostreptococcus vaginalis for group 1 strains, Peptostreptococcus lacrimalis for group 2 strains, and Peptostreptococcus lactolyticus for group 3 strains. The type strain of P. vaginalis is strain GIFU 12669 (= JCM 8138), the type strain of P. lacrimalis is strain GIFU 7667 (= JCM 8139), and the type strain of P. lactolyticus is strain GIFU 8586 (= JCM 8140).  相似文献   
103.
Plasmonics - We numerically analyzed a simple and novel design of multi-broadband plasmonic absorber which consists of a planar array of thin gold square ring structures on dielectric/metal...  相似文献   
104.

The use of plants in treatments has been as old as humanity and it has preserved its popularity for centuries til now because of their availability, affordability and safeness. However, despite their widespread use, safety and quality issues have been major concerns in the world due to industrial- and anthropogenic-based heavy metal contamination risks. Thus, this study was attempted to analyze the heavy metal levels and mineral nutrient status of widely used medicinal plants in Turkey to have insights about their health implications on humans. The plant concentrations of B, Ca, Cd, Cr, Cu, Fe, K, Mg, Mn, Na, Ni, Pb and Zn were analyzed by ICP-OES in the leaves of 44 medical plants purchased from herbal markets of three different districts of Istanbul/Turkey. The measured lowest to highest concentrations were 0.065–79.749 mg kg−1 B, 921.802–12,854.410 mg kg−1 Ca, 0.020–0.558 mg kg−1 Cd, 0.015–4.978 mg kg−1 Cr, 0.042–8.489 mg kg−1 Cu, 34.356–858.446 mg kg−1 Fe, 791.323–15,569.349 mg kg−1 K, 102.236–2837.836 mg kg−1 Mg, 4.915–91.519 mg kg−1 Mn, 10.224–3213.703 mg kg−1 Na, 0.001–5.589 mg kg−1 Ni, 0.003–3.636 mg kg−1 Pb and 2.601–36.102 mg kg−1 Zn. Those levels in plants were in acceptable limits though some elements in some plants have high limits which were not harmful. Variations (above acceptable limits) in element concentrations also indicated that these plants could be contaminated with other metals and that genetic variations may influence accumulation of these elements at different contents. Overall, analyzed medicinal plants are expected not to pose any serious threat to human health.

  相似文献   
105.
106.
The present article describes the synthesis, in vitro urease inhibition and in silico molecular docking studies of a novel series of bi-heterocyclic bi-amides. The synthesis of title compounds was initiated by benzoylation, with benzoyl chloride (1), of the key starter ethyl 2-(2-amino-1,3-thiazol-4-yl)acetate (2) in weak basic aqueous medium followed by hydrazide formation, 4, and cyclization with CS2 to reach the parent bi-heterocyclic nucleophile, N-{4-[(5-sulfanyl-1,3,4-oxadiazol-2-yl)methyl]-1,3-thiazol-2-yl}benzamide (5). Various electrophiles, 8a–l, were synthesized by a two-step process and these were finally coupled with 5 to yield the targeted bi-heterocyclic bi-amide molecules, 9a–l. The structures of the newly synthesized products were corroborated by IR, 1H NMR, 13C NMR, EI-MS and elemental analysis. The in vitro screening of these molecules against urease explored that most of the compounds exhibit potent inhibitory potential against this enzyme. The compound 9j, with IC50 value of 2.58?±?0.02?µM, exhibited most promising inhibitory activity among the series, relative to standard thiourea having IC50 value of 21.11?±?0.12?µM. In silico studies fully augmented the experimental enzyme inhibition results. Chemo-informatics analysis showed that synthesized compounds (9a–l) mostly obeyed the Lipinski's rule. Molecular docking study suggested that ligand 9j exhibited good binding energy value (?7.10?kcal/mol) and binds within the active region of target protein. So, on the basis of present investigation, it was inferred that 9j may serve as a novel scaffold for designing more potent urease inhibitors.  相似文献   
107.
108.
We describe in this report a sensitive and direct method for the analysis of tamoxifen (TAM) in microsamples of plasma. The drug and internal standard (quinine bisulfate, I.S.) were separated on a 10-μm particle, 10 cm × 8 mm CN cartridge in conjuction with a radial compression system. The mobile phase was a mixture of 0.1 M sodium acetate in 0.001 M tetrabutylammonium phosphate solution (pH 6) and methanol (30:70, v/v) at a flow-rate of 4 ml/min. After addition of I.S. and o-phosphoric acid in acetonitrile (0.6 M) to the plasma (30 μl), the mixture was placed in an ultraviolet shortwave transluminator for 2 min prior to injection into the chromatograph. The compounds were detected in the effluent fluorometrically at excitation and emission wavelengths of 258 and 378 nm, respectively. Under these conditions, no interference in the assay from any endogenous substance or other concurrently used drugs was observed and the retention times of I.S. and TAM were 4.4 and 10.15 min, respectively. The concentration of TAM in plasma was linearly (r>0.9983) related to the peak height ratio (TAM/I.S.) in the range 0.01–2.0 μg ml−1 and C.V. at 0.075, 0.4 and 1.2 μg ml−1 was 4.96%. We are currently using this assay for monitoring TAM in plasma and investigating its pharmacokinetics in cancer patients receiving cytotoxic drugs in addition to TAM as a multi-drug resistance modifier.  相似文献   
109.
High temperature is an environmental stress which destroys agricultural crops and inhibits their growth and productivity. The aim of current investigation was to examine the role of selenium (Se) on cucumber (Cucumis sativus L.) cv. Sahil plant growth, physio-biochemical and yield attributes under heat stress (HS) in controlled conditions. Plants were grown under normal temperature (NT; 28/18 °C day/night) from sowing to 32 days after sowing (DAS). All plants were foliar-sprayed with Se (8 µM) at flower-initiation stage (32-DAS) and heat stress (HS; 40/30 °C day/night) was induced from 35-DAS to entire duration of the experiment (75-DAS). Data regarding growth, physio-biochemical and yield traits were measured. Heat stress decreased growth traits, total chlorophyll contents, chlorophyll fluorescence parameters, photosynthesis (Pn), stomatal conductance (g s), transpiration rate (E), antioxidant enzyme activities, membrane stability index (MSI) and yield-related attributes, while increased intercellular CO2 (Ci), ROS production, lipid peroxidation (LPO), non-photochemical quenching (NPQ) and compatible solutes. Exogenous application of Se mitigated HS-induced injurious effects by improving growth components, Pn, g s, E, chlorophyll content, chlorophyll fluorescence parameters, antioxidant enzyme activities, level of osmolytes, MSI and yield attributes and reducing ROS, LPO and NPQ. Selenium reversed heat-induced oxidative damage by strengthening antioxidative mechanism, which resulted in higher scavenging of ROS, thereby minimizing LPO. It is suggested that Se-induced improvement in Pn, growth and productivity associated traits under HS is linked with enhanced antioxidant activities and osmolytes accumulation. In addition, Se applied at flower initiation is highly effective in alleviating heat damage in cucumber.  相似文献   
110.
Endovascular intervention using traditional neurovascular stents and densely braided flow diverters (FDs) have become the preferred treatment strategies for traditionally challenging intracranial aneurysms. Modeling stent and FD deployment in patient-specific aneurysms and its flow modification results prior to the actual intervention can potentially predict the patient outcome and treatment optimization. We present a clinically focused, streamlined virtual stenting workflow that efficiently simulates stent and FD treatment in patient-specific aneurysms based on expanding a simplex mesh structure. The simplex mesh is generated using an innovative vessel-specific initialization technique, which uses the patient’s parent artery diameter to identify the initial position of the simplex mesh inside the artery. A novel adaptive expansion algorithm enables the acceleration of deployment process by adjusting the expansion forces based on the distance of the simplex mesh from the parent vessel. The virtual stenting workflow was tested by modeling the treatment of two patient-specific aneurysms using the Enterprise stent and the Pipeline Embolization Device (commercial FD). Both devices were deployed in the aneurysm models in a few seconds. Computational fluid dynamics analyses of pre- and post-treatment aneurysmal hemodynamics show flow reduction in the aneurysmal sac in treated aneurysms, with the FD diverting more flow than the Enterprise stent. The test results show that this workflow can rapidly simulate clinical deployment of stents and FDs, hence paving the way for its future clinical implementation.  相似文献   
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