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The protein encoded by the pancreatic colipase (CLPS) gene is an essential cofactor needed by pancreatic triglyceride lipase (PNLIP) for efficient dietary lipid hydrolysis. Since the inhibition of lipase activity was shown to reduce the incidence of type 2 diabetes mellitus, we tested the hypothesis that genetic variations in the CLPS and PNLIP genes are associated with type 2 diabetes; 47 unrelated subjects were screened for polymorphisms of the CLPS and PNLIP genes. A nested-case control study of 192 incident type 2 diabetes subjects and 384 sex- and age-matched controls taken from the European Prospective Investigation into Cancer and Nutrition Potsdam Cohort (EPIC) was employed for association studies. The Metabolic Intervention Cohort Kiel (MICK) consisting of 716 males was used for verification. A novel putative functional polymorphism (Arg109Cys) was identified in the CLPS gene. The frequencies of the Arg/Cys genotype were 2.6% in EPIC and 2.2% in MICK study subjects. No homozygotes for the Cys/Cys genotype were found in either study population. Logistic regression analysis showed a statistically significant association of the Arg/Cys genotype with an increased risk of type 2 diabetes. The odds ratios estimated by the model were 3.75 (95%CI = 1.13-12.49, p = 0.03) in EPIC and 4.86 (95%CI = 1.13-20.95, p = 0.03) in MICK. No comparable associations were found with other traits of the insulin-resistance syndrome (e. g.; body mass index, waist to hip ratio). In conclusion, we obtained evidence in two German Caucasian study populations that the variant of the rare CLPS Arg109Cys polymorphism might contribute to increased susceptibility of type 2 diabetes.  相似文献   
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Characteristic process parameters and variables in catalytic fluidized bed cracking . Catalytic fluidized-bed cracking occupies a distinctive position among the various conversion processes. With regard to its favorable product range, the process is characterized by low processing costs coupled with flexibility of raw materials. A number of independent process parameters are available for control of the reactions involved in catalytic cracking and for influencing the product range. The cracking reactions taking place and the interplay of the independent and dependent variables are described. Apart from the actual cracking process, particular importance attaches to the regeneration of the catalyst charged with coke since it has a decisive influence on the thermal economy of the plant. Depending upon the desired product yield or the raw materials a suitable catalyst must be chosen. Considerable progress has recently been made in catalyst development.  相似文献   
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To achieve a high productivity and low costs in modern steelmaking, for example, oxygen top blow,bottom blow and combined processes, the following problems have been discussed in detail: (1) Sampling problems (data aquisition, precision, reliability); (2) Process problems (mostly of metallurgical and technological kind); (3) Method specific problems (choice of the analysis method).  相似文献   
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Contextualizing ontologies   总被引:2,自引:0,他引:2  
Ontologies are shared models of a domain that encode a view which is common to a set of different parties. Contexts are local models that encode a party’s subjective view of a domain. In this paper, we show how ontologies can be contextualized, thus acquiring certain useful properties that a pure shared approach cannot provide. We say that an ontology is contextualized or, also, that it is a contextual ontology, when its contents are kept local, and therefore not shared with other ontologies, and mapped with the contents of other ontologies via explicit (context) mappings. The result is Context OWL (C-OWL), a language whose syntax and semantics have been obtained by extending the OWL syntax and semantics to allow for the representation of contextual ontologies.  相似文献   
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Results of investigations concerning the determination of the influence of the water quality on the heat transfer of quenched hot metal surfaces are presented. With an immersion quenching device, tests have been carried out for various cooling water qualities. Apparently there was no correlation between the water quality and the cooling process (Leidenfrost temperature). High concentrations of dissolved gases yield stable vapour films (low Leidenfrost temperatures are measured). Salt displaces the dissolved gases from the water; the Leidenfrost temperature rises: the higher the salt concentration, the lower the gas concentration and, therefore, the higher the Leidenfrost temperature. If salt concentrations are high or the cooling water is degassed, the vapour film falls apart just after Immersion. An extended model considering the Influence of the gases allows the correlation of the water quality/salt concentration and the heat transfer/Leidenfrost temperature.  相似文献   
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