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31.
Since liver fatty acid binding protein (L-FABP) facilitates uptake/oxidation of long-chain fatty acids in cultured transfected cells and primary hepatocytes, loss of L-FABP was expected to exacerbate weight gain and/or obesity in response to high dietary fat. Male and female wild-type (WT) and L-FABP gene-ablated mice, pair-fed a defined isocaloric control or high fat diet for 12 weeks, consumed equal amounts of food by weight and kcal. Male WT mice gained weight faster than their female WT counterparts regardless of diet. L-FABP gene ablation enhanced weight gain more in female than male mice—an effect exacerbated by high fat diet. Dual emission X-ray absorptiometry revealed high-fat fed male and female WT mice gained mostly fat tissue mass (FTM). L-FABP gene ablation increased FTM in female, but not male, mice—an effect also exacerbated by high fat diet. Concomitantly, L-FABP gene ablation decreased serum β-hydroxybutyrate in male and female mice fed the control diet and, even more so, on the high-fat diet. Thus, L-FABP gene ablation decreased fat oxidation and sensitized all mice to weight gain as whole body FTM and LTM—with the most gain observed in FTM of control vs high-fat fed female L-FABP null mice. Taken together, these results indicate loss of L-FABP exacerbates weight gain and/or obesity in response to high dietary fat.  相似文献   
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Praxis&Wissen

Einchecken in der Business Class! Lage- und Qualit?tsprüfung bei Zuführsystemen  相似文献   
34.
Carotenoids from tomatoes inhibit heterocyclic amine formation   总被引:1,自引:0,他引:1  
Tomatoes are a rich source of antioxidants and they are commonly used for meat cooking in Mediterranean countries. The effects of tomato antioxidants on the formation of carcinogenic/mutagenic heterocyclic amines were investigated. A liquid model system containing as precursors creatinine, glucose and glycine in molar concentrations comparable to those present in bovine meat (chemical model system) was employed. A freeze-dried bovine meat juice (meat juice model system) was also used for some experiments. In both model systems, an inhibiting effect of tomato carotenoid fraction on the formation of imidazoquinolines (IQx, MeIQx and DiMeIQx) was observed. Using carotenoid extract at a concentration of 1000 ppm, inhibitions of 36% and 11% of IQx and MeIQx formation respectively in the chemical system and of 13% of MeIQx and of 5% of 4,8-DiMeIQx in the meat juice system was observed. The effect of the main tomato flavonoid, quercetin, was investigated using the meat juice system. Quercetin gave an inhibition of MeIQx formation between 9% and 57% with a maximum effect of 67% at 10 ppm.  相似文献   
35.
Computer supported collaborative work (CSCW) allows people to cooperate by computers from different places and at different times. To enable an easier integration of such collaborative components into web-based communities and portals, a Shared Workspace Open Framework (SWOF) was developed. This framework provides the basic features of shared workspaces and can be customized to different cooperation cases. High usability is an important aspect of the implementation. To achieve these aims SWOF focuses on an information space with more task-suited item-types that can help to pre-structure the information. Thus, on the one hand the system can help the users to write down the needed information in a consistent way and, on the other, could reduce the arguments between the group members on how to structure their workspace. As a use case for SWOF the development of a Web-based portal for the community of man-machine interaction was chosen. In the project MMI-Interaktiv, a portal is built with a SWOF-based shared workspace component. An evaluation for this use case is presented.  相似文献   
36.
Indirect immunofluorescence studies revealed that when fixed, permeabilized cultured human cells were incubated with ricin A chain, the toxin molecule localized in a staining pattern indicative of binding to the endoplasmic reticulum and to nucleoli. Chemical cross-linking experiments were performed to identify the cellular components that mediated the binding of ricin A chain. Conjugates were formed between 125I-labeled ricin A chain and two proteins present in preparations of total cell membranes and in samples of purified mammalian ribosomes. Specificity of the ricin A chain-ribosome interaction was demonstrated by inhibition of formation of the complexes by excess unlabeled ricin A chain, but not by excess unlabeled gelonin, another ribosome-inactivating protein. Complexes of ricin A chain cross-linked to the ribosomal proteins were purified and subjected to proteolytic digestion with trypsin. Amino acid sequencing of internal tryptic peptides enabled identification of the ricin A chain-binding proteins as L9 and L10e of the mammalian large ribosomal subunit.  相似文献   
37.
Accurate assessment of human intake of mutagenic/carcinogenic heterocyclic amines (HAs) is necessary for epidemiological studies and future risk assessment. Using questionnaires, the frequency of consumption of specific dishes can be obtained at an individual level and linked to analyzed concentrations of different compounds in corresponding dishes. Some typical Swedish cooked meat dishes, hamburgers and kebab, industrially prepared or from fast food outlets and restaurants, were analyzed regarding their content of 11 different HAs. The amount of each of these compounds was below 0.1 ng/g cooked weight in most of the industrially prepared products. The total amount of HAs was highest in the kebab samples. The intake of HAs from 200 g of the dishes was estimated to range from not detectable levels to 0.6 microg. The results of the present study indicate that the content of HAs in a specific dish may vary with origin, and that the concentrations of HAs in commercial fried meat products are generally low, although some of these food items may contain elevated amounts.  相似文献   
38.
Company websites are an important instrument for relationship marketing activities. We present a methodological framework that aligns website performance assessment and marketing intelligence for evaluating the performance of relationship marketing activities. In this context, we develop an extended web mining approach that integrates managerial perspectives in the analyst’s investigation of the customer-website interaction based on historical clickstream data.This approach enables quantification of the moderating effect of a website’s structure and content regarding website-based relationship marketing. The applicability of our approach is demonstrated by clickstream data of 477,471 visitor sessions on a software developer’s website. The results provide detailed insights into the usage behavior on a website and the mechanisms to enhance e-commerce efficiency via website optimization.  相似文献   
39.
Research results are commonly circulated on the occasion of congresses or by publication in technical journals. steel research, the scientific journal edited by the Verein Deutscher Eisenhüttenleute, VDEh ‐ The German Iron and Steel Institute, and the Max‐Planck‐Institut für Eisenforschung, MPI, presents the latest results of fundamental research in the fields of process metallurgy, metal working and materials science as far as the material steel is concerned. Formerly well‐known as ?Archiv für das Eisenhüttenwesen“, steel research looks back on 70 years of experience in worldwide exchange of technological basics. In 1995, the editors decided to offer a Best Paper Award with 1.000 US‐$ purse and a pretty diploma. This year, it was for the fifth time that authors have been awarded with the steel research Best Paper Award. The Editorial Board has chosen a contribution to TRIP steels from the papers published in the 1999 annual volume.  相似文献   
40.
单面低加料率的涂层辊筒装置应用在非织造布工业中有着悠久的历史,绝大多数用于非织造尿布顶层的低加料率,单面亲水或永久亲水.Andritz Ktisters(安德里兹寇司德)为进行高速生产的非织造布工业客户(速度高至1000m/min)提供量身定做的neXkiss涂层辊筒产品系列.最新开发的neXkiss plus拥有特殊的灵活性和最大的生产多功能性.  相似文献   
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