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131.
ST segment elevation myocardial infarction (STEMI) is one of the most common global causes of cardiovascular disease-related death. Several metabolites may change during STEMI. Hence, analysis of metabolites in body fluid may be considered as a rapid and accurate test for initial diagnosis. This study has therefore attempted to determine the variation in metabolites identified in the serum of STEMI patients (n = 20) and 15 controls. Samples collected from the Cardiology Department, Medical Faculty, Ataturk University, were extracted by liquid–liquid extraction and analysed using liquid chromatography quadrupole time-of-flight mass spectrometry. The METLIN database was used for the identification and characterization of metabolites. According to Q-TOF/MS measurements, 231 m/z values, which were significantly different between groups (P < 0.01 and fold analysis >1.5) were detected. Metabolite identification was achieved via the Human Metabolome database. According to the multivariate data analysis, leucine, isoleucine, l -proline, l -alanine, glycine, fumaric acid, citrate, succinate and carnitine levels were decreased, whereas levels of propionic acid, maleic acid, butyric acid, urea, oleic acid, palmitic acid, lysoPC [18:2(9Z)], glycerol, phoshpatidylethanolamine, caffeine and l -lactic acid were increased in STEMI patients compared with controls. In conclusion, malonic acid, maleic acid, fumaric acid and palmitic acid can be used as biomarkers for early risk stratification of patients with STEMI.  相似文献   
132.
Drought tolerance is an important breeding objective in dry and semi-dry conditions. Carbon isotope discrimination (Δ) is a tool that may be used to improve water-use efficiency (WUE) as an indirect selection criterion. The study investigated the variability for Δ in improved F7 lines and their parents (three cultivars and two mutant lines), which were sampled randomly from an F6 nursery performing well under semi-dry conditions. In total, 40 entries were grown in sand culture, arranged in three-replicated randomized complete block designs in two sets of experiments in Antalya, Turkey. There were statistically significant differences (p<0.01) among genotypes in both sets of experiments for Δ, and Δ values range from 20.14 to 21.86. Low coefficient of variation (C.V.) values, i.e. 2 and 1.65 %, for both data sets revealed efficient control of experimental error for Δ and indicated little effect of environment. Consequently, broad-sense heritability estimates for Δ were 0.63 and 0.74. As Δ showed a considerably high heritability and consistency over the two sets of experiments and low C.V. values, it was concluded that this trait could be used in breeding programmes aimed at developing drought tolerance lines. The early heading mutant, M-K-88, and the cultivar selected from land race, Tokak 157-37, showed lowest Δ values, indicating that they had the best water-use efficiency. Low Δ values of these two genotypes were inheritable.  相似文献   
133.
Double‐armed crown ether aldehydes ( 1–3 ) were synthesized from the reaction of 2 equiv salicylaldehyde, 4‐hydroxy‐3‐methoxybenzaldehyde (vanillin), and 3‐hydroxy‐4‐methoxybenzaldehyde (iso‐vanillin) with 4′,5′‐bis(bromomethyl)benzo‐15‐crown‐5. New crown ethers imine compounds ( 4–9 ) were synthesized by the condensation of corresponding crown ether aldehydes ( 1–3 ) with 4‐amino‐1,2‐dihydro‐1,5‐dimethyl‐2‐phenyl‐3H‐pyrazole‐3‐one and 2‐furan‐2‐yl‐methylamine. Sodium complexes ( 1a–9a) of the crown compounds form crystalline 1:1 (Na+:ligand) stoichiometries and were also synthesized. The structures of the crown ether aldehydes ( 1–3 ), imine compounds ( 4–9 ), and complexes ( 1a–9a ) were confirmed on the basis of elemental analyses, IR, 1H and 13C NMR, and mass spectrometry. © 2013 Wiley Periodicals, Inc. Heteroatom Chem 24:100–109, 2013; View this article online at wileyonlinelibrary.com . DOI 10.1002/hc.21070  相似文献   
134.
Gurkan UA  Anand T  Tas H  Elkan D  Akay A  Keles HO  Demirci U 《Lab on a chip》2011,11(23):3979-3989
Selective capture of cells from bodily fluids in microchannels has broadly transformed medicine enabling circulating tumor cell isolation, rapid CD4(+) cell counting for HIV monitoring, and diagnosis of infectious diseases. Although cell capture methods have been demonstrated in microfluidic systems, the release of captured cells remains a significant challenge. Viable retrieval of captured label-free cells in microchannels will enable a new era in biological sciences by allowing cultivation and post-processing. The significant challenge in release comes from the fact that the cells adhere strongly to the microchannel surface, especially when immuno-based immobilization methods are used. Even though fluid shear and enzymes have been used to detach captured cells in microchannels, these methods are known to harm cells and affect cellular characteristics. This paper describes a new technology to release the selectively captured label-free cells in microchannels without the use of fluid shear or enzymes. We have successfully released the captured CD4(+) cells (3.6% of the mononuclear blood cells) from blood in microfluidic channels with high specificity (89% ± 8%), viability (94% ± 4%), and release efficiency (59% ± 4%). We have further validated our system by specifically capturing and controllably releasing the CD34(+) stem cells from whole blood, which were quantified to be 19 cells per million blood cells in the blood samples used in this study. Our results also indicated that both CD4(+) and CD34(+) cells released from the microchannels were healthy and amenable for in vitro culture. Manual flow based microfluidic method utilizes inexpensive, easy to fabricate microchannels allowing selective label-free cell capture and release in less than 10 minutes, which can also be used at the point-of-care. The presented technology can be used to isolate and purify a broad spectrum of cells from mixed populations offering widespread applications in applied biological sciences, such as tissue engineering, regenerative medicine, rare cell and stem cell isolation, proteomic/genomic research, and clonal/population analyses.  相似文献   
135.
Freight transportation is a major component of logistical operations. Due to the increase in global trade, fierce competition among shippers and raising concerns about energy, companies are putting more emphasis on effective management and usage of transportation services. This paper studies the transportation pricing problem of a truckload carrier in a setting that consists of a retailer, a truckload carrier and a less than truckload carrier. In this setting, the truckload carrier makes his/her pricing decision based on previous knowledge on the less than truckload carrier’s price schedule and the retailer’s ordering behavior. The retailer then makes a determination of his/her order quantity through an integrated model that explicitly considers the transportation alternatives, and the related costs (i.e., bimodal transportation costs) and capacities. In the paper, the retailer’s replenishment problem and the truckload carrier’s pricing problem are modeled and solved based on a detailed analysis. Numerical evidence shows that the truckload carrier may increase his/her gainings significantly through better pricing and there is further opportunity of savings if the truckload carrier and the retailer coordinate their decisions.  相似文献   
136.
<正>The title compound,trans-bis(acesulfamato-O)tetraaquazinc(Ⅱ)(I,C_8H_(16)N_2O_(12)S_2Zn), crystallizes in the triclinic system,space group P_1~-with a=5.1638(5),b=8.5338(9),c=9.9583(9) (?),a=74.325(8),β=81.112(7),γ=75.800(8)°,V=407.77(7)(?)~3,Z=1,F(000)=236,R_(int)=0.085, T=296 K,the final R=0.029 and wR=0.078 for 1832 observed reflections with I2σ(I).The Zn~Ⅱcentre resides on a centre of symmetry and has a distorted octahedral geometry.The basal plane is defined by two carbonyl O atoms of two monodentate trans-oriented acesulfamato ligands and two trans-aqua ligands.The axial positions in the octahedron are occupied by two trans-aqua ligands. Intermolecular O-H…O hydrogen bonds produce R_2~2(8)and R_2~2(16)rings,which lead to two-dimensional polymeric chains.  相似文献   
137.
The article describes the syntheses and extraction properties of new lactam ionophores. These lactam derivatives were easily synthesized via aminolysis of dimethyl 2,2′-(6,6′-methylenebis(2-tert-butyl-4-methyl-6,1-phenylene)bis(oxy))diacetate or dimethyl 2,2′-(2,2′-methylenebis(4-chloro-2,1-phenylene))bis(oxy)diacetate with corresponding diamine compounds at one step. The extraction studies of lactam ionophores were performed toward dichromate anion and alkaline and transition metals such as Li+, Na+, K+, Co2+, Hg2+ and Pb2+. All the structures of the ionophores were confirmed by spectroscopic techniques and elemental analysis.  相似文献   
138.
A series of piano‐stool Ru (II) complexes ( Ru 1–7 ) bearing ethylenediamine with aryl and aliphatic groups were prepared and fully characterized by 1H, 13C, 19F and 31P NMR spectroscopy, FT‐IR and elemental analysis. The crystal structures of Ru 2–4 and Ru 7 were determined by X‐ray crystallography. They were successfully applied to the alpha(α)‐alkylation of aliphatic and aromatic ketones with alcohols via the borrowing hydrogen strategy in mild reaction conditions within a short time. The catalytic system has a broad substrate scope, which allows the synthesis of alpha alkylated ketones with excellent yields. The electronic and steric effects of complexes on catalytic activity were analysed. The influence of the carbon chain length of the ligand on the alpha‐alkylation reaction of ketones was also investigated. The catalytic cycle was also examined by 1H‐NMR spectroscopy in d8‐toluene.  相似文献   
139.
The determination of di(2-ethylhexyl) phthalate migration was achieved in artificial sweat using gas chromatography mass spectrometry following activated carbon enrichment of samples. Response surface methodology (RSM) was used to optimise the conditions for maximum recovery and to understand the significance and interaction of the factors affecting the recovery of di(2-ethylhexyl) phthalate. The best compromise of analytical conditions for the simultaneous determination of analyte from spiked artificial sweat was found to be: pH (3.1), activated carbon amount (1.4 g L?1), adsorption time (55 min) and elution solvent (chloroform). These conditions were applied to study the migration of di(2-ethylhexyl) phthalate from different children’s toys into artificial sweat. The detection limit of the method was 13.8 μg L?1, while the relative standard deviation (%) value for the analysis of 100 μg L?1 of the analyte was below 3.7% (n = 5).  相似文献   
140.
The present article deals with M-soliton solution and N-soliton solution of the (2 + 1)-dimensional asymmetrical Nizhnik–Novikov–Veselov equation by virtue of Hirota bilinear operator method. The obtained solutions for solving the current equation represent some localized waves including soliton, breather, lump, and their interactions, which have been investigated by the approach of the long-wave limit. Mainly, by choosing the specific parameter constraints in the M-soliton and N-soliton solutions, all cases of the one breather or one lump can be captured from the two, three, four, and five solitons. In addition, the performances of the mentioned technique, namely, the Hirota bilinear technique, are substantially powerful and absolutely reliable to search for new explicit solutions of nonlinear models. Meanwhile, the obtained solutions are extended with numerical simulation to analyze graphically, which results in localized waves and their interaction from the two-, three-, four-, and five-soliton solutions profiles. They will be extensively used to report many attractive physical phenomena in the fields of acoustics, heat transfer, fluid dynamics, classical mechanics, and so on.  相似文献   
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