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111.
A convenient method was developed for preparation of FAME in small amounts from glycerolipids of blood or breast milk. Initially, 0.04–0.06 mL blood or breast milk was spotted onto a small piece of filter paper (1.5×1.5 cm) that had been washed with acetone containing 0.05% 2,6-di-tert-butyl-p-cresol (BHT). Fach piece, once it had dried, was put in a small test tube, to which 2 mL hexane and 0.2 mL 2 M KOH/methanol were added. After vigorous mixing or sonication for 2 min at room temperature, the solution was neutralized or acidified by the addition of a few drops of acetic acid. To the solution was added 2 mL H2O, and then the hexane layer that separated was concentrated to dryness in vacuo. The FAME obtained were analyzed by GC. The method was applicable to the analysis of a large number of blood and breast milk samples, and the arachidonate/(eicosapentaenoate +docosahexaenoate) ratios could be determined rapidly.  相似文献   
112.
In this paper, the potential for sub-10-nm junction formation of partial-melt laser annealing (PMLA), which is a combination of solid-phase regrowth and heat-assisted laser annealing (HALA), is demonstrated. HALA and PMLA are effective for reducing laser-energy density for dopant activation and for improving heating uniformity of device structure. The absence of melting at the dopant profile tail for PMLA results in a negligibly small diffusion at this region. A high activation rate is achievable by melting the upper part of the amorphous-silicon layer. The obtained sheet resistance of 10-nm-deep junctions was about 700 /spl Omega//sq. for both n/sup +//p and p/sup +//n junctions. These results imply that PMLA is applicable for much shallower junction formation.  相似文献   
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A series of cephalosporin derivatives with a thiazolopyridinium group at the 3-position was synthesized and evaluated for antibacterial activity. Some of these cephalosporin derivatives having a (5-alkylthiazolo[4,5-c]pyridinium-2-yl)thiomethyl group at the 3-position showed strong activity against Gram-positive and Gram-negative bacteria, including Pseudomonas aeruginosa. Among them, 5a showed a good antibacterial spectrum in vitro, and also showed a similar or slightly superior activity to that of ceftazidime in vivo against P. aeruginosa.  相似文献   
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The effects of hemodynamic changes on intraaortic balloon (IAB) volumes were studied experimentally using a helium tachometer in a mock circulatory system. The IAB volume decreased with increases in the heart rate and mean aortic pressure, but the degree of reduction in the IAB volume was different among 4 commercially available IAB drivers. Improvements in IAB consoles are needed to compliment the progress made in percutaneous techniques for IAB insertion resulting in smaller balloons.  相似文献   
118.
The dispersion of filler in resin is an important factor which determines the mobility of a compound in a molder and also the mechanical properties of molded products in wood/plastic composite, especially with high wood filler content. In this report, the dispersion of components in the melt‐mixture of a compound in response to the size of cellulose filler and resin content was examined for compounds with a high content of cellulose in polypropylene by the evaluation of viscoelasticity using a cone rheometer, and the following conclusions were obtained: (1) The viscoelasticity measured by a cone rheometer was dependent on the dispersion state of the compound, and it was confirmed that the presented evaluation method of viscoelasticity affords information relevant to the dispersion state of filler in a compound; (2) On the basis of the viscoelastic evaluation of compounds with different resin contents, a model for the distribution of cellulose and resin is proposed in terms of the tangle of fibers; (3) Viscoelastic analysis showed that cellulose size has an influence on the tangle of fibers; (4) The results of viscoelasticity and mechanical properties of molded products suggested that an important factor determining the tangle of fibers is the average aspect ratio. The proposed analysis of viscoelasticity presents a simple technique for estimating the dispersion state of a compound with high filler content, which is hardly possible by conventional fluid evaluation methods. POLYM. ENG. SCI., 48:168–176, 2008. © 2007 Society of Plastics Engineers  相似文献   
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Domain names are at the base of today’s cyber-attacks. Attackers abuse the domain name system (DNS) to mystify their attack ecosystems; they systematically generate a huge volume of distinct domain names to make it infeasible for blacklisting approaches to keep up with newly generated malicious domain names. To solve this problem, we propose DomainProfiler for discovering malicious domain names that are likely to be abused in future. The key idea with our system is to exploit temporal variation patterns (TVPs) of domain names. The TVPs of domain names include information about how and when a domain name has been listed in legitimate/popular and/or malicious domain name lists. On the basis of this idea, our system actively collects historical DNS logs, analyzes their TVPs, and predicts whether a given domain name will be used for malicious purposes. Our evaluation revealed that DomainProfiler can predict malicious domain names 220 days beforehand with a true positive rate of 0.985. Moreover, we verified the effectiveness of our system in terms of the benefits from our TVPs and defense against cyber-attacks.  相似文献   
120.
Two-dimensional crystals of rat microsomal glutathione transferase were grown during dialysis of detergent-solubilized enzyme after addition of a small amount of phospholipid. The crystals had two-sided plane group symmetry p21212 with a calibrated unit cell size of a=91.90 A, b=90.83 A. Electron diffraction patterns were recorded showing significant reflections extending to 3.0 A. A combination of these structure factor amplitudes with phases from high-resolution images following image processing was used to calculate a projection map of the protein. The asymmetric unit of the structure consists of three microsomal glutathione transferase molecules. The local 3-fold axis at the center of the trimer is delineated by six parallel alpha-helices, two from each monomer. The two helices differ significantly in their respective projection structure. The inner helical core of the trimer is partly surrounded by elongated domains with extensions towards the helices and which contain resolved density maxima at a spacing of 4 to 5 A. A well-defined strong peak is localized close to the elongated domain and at a distance of about 9.5 A from two of the inner helices.  相似文献   
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