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51.
Fish are an excellent source of lean protein and omega-3 polyunsaturated fatty acids (PUFAs) but there is inadequate information on the levels of PUFAs in freshwater fish and specifically Great Lakes fish. Knowledge of PUFAs is necessary to make informed decisions regarding the balance between the benefits of fish consumption due to these factors versus risks of adverse health effects associated with elevated levels of contaminants known to be present in some Great Lakes fish and linked to increased risk of cancer and adverse neurological effects to both infants and adults. Our goal was to determine the lipid profiles in two species of Great Lakes fish, lake trout and whitefish. Total fat and the percentage of total and omega-3 PUFAs were with one exception significantly higher in lake trout than whitefish. Average concentrations of EPA + DHA were 11.2 and 9.7 g/100 g lipid in lake trout and whitefish, respectively. The concentrations of EPA + DHA in fatty marine fish (22.7, 23.9 and 30.2 g/100 g lipid, respectively) are about double those found in Great Lakes lake trout and whitefish. Nevertheless a 100 g serving of Great Lakes lake trout provides more than 500 mg of EPA + DHA, which is the daily intake level recommended by the American Dietetics Association for the prevention of coronary heart disease.  相似文献   
52.
Zusammenfassung  Die Aufgabe des Data-Mining-Cups 2007 war die Entwicklung einer vollautomatischen Methode zur effektiven Steuerung des Einsatzes von Rabattcoupons. Vorverarbeitung und Parameter wurden durch eine Kreuzvalidierung optimiert. Experimente zeigen, dass ein einzelner Klassifikator in der Regel nicht genügt, die Aufgabenstellung mit ausreichender Güte zu l?sen. Vielmehr müssen mehrere, m?glichst verschiedene, Klassifikatoren dazu herangezogen werden. Die eingereichten L?sungen entstanden durch Kombination von bis zu 2.000 Klassifikatoren und haben im Wettbewerb sehr gut abgeschnitten: Sechs von neun Abgaben lagen unter den ersten zehn Pl?tzen, die übrigen drei L?sungen sind immer noch unter den ersten 20 von insgesamt 230 Pl?tzen.  相似文献   
53.
Inactivation of tumor suppressor genes like p53 and p16 play a key role in tumor progression, with a high incidence of mutations existing for both genes in oral squamous cell carcinomas. Previous studies have demonstrated, (i) a correlation between the prevalence of p53 mutations and tobacco use [Brennan et al. (1995) New Engl. J. Med., 332, 712-717; Lazarus et al. (1996) Carcinogenesis, 17, 733-739], and (ii) a link between genotypes in specific xenobiotic metabolizing enzymes and oral cancer susceptibility [Park et al. (1997) Cancer Epid. Biomarkers Prev., 6, 791-797). In this paper, we present results of our examination of a series of 80 oral squamous cell carcinomas for p53 exons 5-9 and p16 exons 1-2 mutations, and the potential association of these mutations with specific genotyping patterns. p53 mutation prevalence in oral tumors was linked with increased patient tobacco use using several stratification criteria. There was a significantly higher prevalence of p53 mutations in OCSCCs from patients who smoked > 30 pack-years as compared to tumors from patients who smoked < or = 30 pack-years (OR = 2.8; CI = 1.1-7.2). No significant association was observed with patient alcohol consumption. There was a significant association between the prevalence of p53 mutations in oral tumors and CYP1A1 genotyping patterns in these oral cancer patients, with the highest p53 mutation prevalence observed in subjects with the CYP1A1 [val]/GSTM1 [+] genotype (OR = 6.0; CI = 1.2-29.7). A significant association was not observed between the prevalence of p16 mutations in oral tumors and tobacco use, or CYP1A1 [val] or GSTM1 (0/0) genotypes. These data suggest that the induction of mutations in specific tumor suppressor genes or oncogenes in oral tumors may be associated with specific carcinogen exposures, and that this association may be linked to specific polymorphic genotypes in xenobiotic-metabolizing enzyme genes.  相似文献   
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The stability of polycyclic aromatic hydrocarbons (PAHs) in frozen mussel tissue (stored at -80 °C and -120 °C was assessed by analyzing samples of SRM 1974 and SRM 1974a, Organics in Mussel Tissue (Mytilus edulis), since the initial certification analyses. Results of analyses of SRM 1974 and SRM 1974a after 10 years and 6 years of storage, respectively, indicate that the PAH concentrations have not changed. Comparison of results from the analyses of frozen versus freeze-dried mussel tissue samples indicate significant losses of the more volatile PAH such as naphthalene and methylnaphthalenes during the freeze-drying process.  相似文献   
56.
The National Institute of Standards and Technology (NIST) recently issued SRM 1649a, Urban Dust, with certified and reference values for 44 polycyclic aromatic hydrocarbons (PAHs). This material is a recertification of SRM 1649 which was issued in 1982 with certified values for only five PAHs. The PAHs were determined using the following analytical techniques: (1) reversed-phase liquid chromatography with fluorescence detection (LC-FL) for analysis of the total PAH fraction, (2) reversed-phase LC-FL for analysis of isomeric PAH fractions isolated by normal-phase LC (i.e., multidimensional LC), and (3) gas chromatography/mass spectrometry (GC/MS) for analysis of the PAH fraction using three different stationary phases, each with different selectivity for PAH separations. The results from the different techniques are compared and discussed. SRM 1649a is currently the most extensively characterized environmental matrix SRM with respect to PAH constituents.  相似文献   
57.
The last decade has seen the rapid evolution of computer communication networks from research curiosities to operational utilities. The Arpanet,1for example, currently supports communication among more than 100 computer systems and is used daily by hundreds of users. Commercial networks, such as Telenet2in the United States and Datapac3in Canada, have very bright futures. One attraction of these networks is their ability to provide access to a wide variety of resources distributed among the connected computers.  相似文献   
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59.
High-volume data entry jobs are common in such vertical market applications as insurance claims processing and tax reporting; however, the task of effectively reading the data that is hand-printed on various paper forms remains a challenge. The reading capabilities of two types of optical character recognition (OCR) systems are improving the accuracy and reducing the cost of large data entry jobs.  相似文献   
60.
The purpose of a cancer staging system is to encompass all attributes of a tumor that define its life history. We propose a biological staging system which incorporates all of the phases of the natural history of head and neck cancer beginning with the earliest cellular changes extending through the early phase of invasion to the occurrence of metastasis and, finally, culminating in therapeutically refractory disease. This temporally structured system recognizes the importance of constitutional predisposition, and the impact of environmental factors. The intent is to augment the AJCC/UICC staging system and use this system to provide a framework which will easily incorporate current and future advances in basic science, prevention, therapy and palliation which will improve the quality and quantity of life for patients.  相似文献   
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