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11.
J E Celis G P Ratz P Madsen B Gesser J B Lauridsen K P Hansen S Kwee H H Rasmussen H V Nielsen D Crüger 《Electrophoresis》1989,10(2):76-115
Databases of protein information from human embryonal lung fibroblasts (MRC-5) have been established using computer analyzed two-dimensional gel electrophoresis. One thousand four hundred and eighty-two cellular proteins (1060 with isoelectric focusing and 422 with nonequilibrium pH gradient electrophoresis, in the first dimension) ranging in molecular mass between 8 and 234 kDa were separated and numbered. Information entered in the database (in most cases for major proteins) includes: protein name, HeLa protein catalog number, mouse protein catalog number, proteins matched in transformed human epithelial amnion cells (AMA) and peripheral blood mononuclear cells (PBMC), transformation and/or proliferation sensitive proteins, synthesis in quiescent cells, cell cycle regulated proteins, mitochondrial and heat shock proteins, cytoskeletal proteins and proteins whose synthesis is affected by interferons. Additional information entered for a few transformation-sensitive proteins that have been selected for future studies includes levels of synthesis and amounts in fetal human tissues. A total of four hundred and seventy-six [35S]methionine labeled polypeptides (258 isoelectric focusing; 218, nonequilibrium pH gradient electrophoresis) secreted by MRC-5 fibroblasts were separated and recorded (J. E. Celis et al., Leukemia 1987, 1, 707-717). Information entered in this database includes molecular weight and transformation sensitive proteins. These databases, as well as those of epithelial and lymphoid cell proteins (J. E. Celis et al., Leukemia 1988, 9, 561-601), represent the initial stages of a systematic effort to establish comprehensive databases of human protein information. In the long run, these databases are expected to offer a useful framework in which to focus the human genome sequencing effort. 相似文献
12.
A heuristic method for dispatching repair men 总被引:2,自引:0,他引:2
A company has to provide service to its customers. A service consists of a visit to the customer plus the spending of some given time at the scene. The future customer demand is not known but the probability distribution for the demand may be known. When a customer call comes in, the company must immediately specify a time window within which the start of service will be provided. The problem is for a fixed service level to determine an optimal strategy of route design and time window setting so that the total distance travelled is minimized over the time horizon given. A heuristic method BARTOC (Booking Algorithm for Routing and Timing Of Customers) to solve the problem mentioned above is suggested. BARTOC is based on a cluster-first route-second approach. Some computational results are presented. The results indicate that BARTOC produces high quality solutions.Peter Matthiesen, Inc.Dano Chemo, Inc. 相似文献
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Four N,N-disubstituted 2-cyano-Δ7-hexahydroindolium salts, 1, have been reduced at a mercury cathode in aqueous buffered solutions at intermediate pH-values. From the catholyte the following products were isolated and identified: 2-(β-cyanoethyl)-cyclohexanone, 5, a secondary amine, 4, and a mixture of cis-trans isomeric tertiary 2-(β-cyanoethyl) cyclohexylamines, 6. A reaction path via the protonated enamine 3 is proposed based on the pH-dependence of the composition of the product mixture and a few reductions in DMF solution. 相似文献
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Modified nucleosides in human serum. 总被引:1,自引:0,他引:1
E P Mitchell L Evans P Schultz R Madsen J W Yarbro C W Gehrke K Kuo 《Journal of chromatography. A》1992,581(1):31-40
Methylated purines and pyrimidines derived from the degradation of transfer ribonucleic acid have been shown to be excreted in abnormal amounts in the urine of patients with cancer. Recent technology developed by Gehrke and Kuo has allowed the separation and quantification of modified nucleosides in serum using reversed-phase high-performance liquid chromatography with diode-array measurement. Serum levels of ten modified nucleosides were measured in 37 normal healthy adults to establish normal values and to correlate activity with age and sex. In addition, serum levels of patients with several malignancies were measured to determine activity in these diseases. Levels of modified nucleosides in normal individuals were consistently reproducible and showed no significant variation among males versus females or with age. Patients with malignant diseases showed consistent elevations and these were highest in patients with more advanced disease. The evidence of no significant differences in the mean levels of modified nucleosides in serum with age or sex in normal adults and elevations in patients with malignancies demonstrate the potential value of modified nucleosides as cancer biomarkers. 相似文献
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The present investigation is part of a project concerning improvements of the working environment for polymer manufacturing processes at high temperatures; for example, welding and extrusion coating.The evolution of gaseous degradation products from unstabilized and antioxidant stabilized low-density polyethylene during thermo-oxidation in air at 210°C has been studied by a simple technique using a modified gas chromatograph. Of the thirteen antioxidants investigated (phenols, phosphites, phosphonites, sulphides and metal dithiocarbamates), only phenols (radical scavengers) effectively suppress the formation of gaseous degradation products from the polymer during an induction period.The gaseous degradation products were analysed with combined gas chromatography-mass spectrometry (GC-MS), using direct trapping on the GC column (Porapak® QS). Apart from water and carbon dioxide, the major products are formaldehyde, acetaldehyde, formic and acetic acids. The addition of effective antioxidants strongly reduces the absolute amounts of the degradation products during the induction period, but does not change their relative quantities. 相似文献