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181.
182.
Conventional and SYBR Green Q Rti-PCR assays using primers targeting the 12S rRNA of chicken mitochondrial genes were employed for the detection and quantification of chicken used in food stuffs. The assays were recruited to amplify different known concentrations of DNA in the mixtures. Different kinds of processed meats were prepared using various amounts of chicken that were heated at different temperatures in order to detect the chicken in the mixtures. The PCR amplification of DNA revealed that the assay can amplify the species-specific amplicons as little as 0.01 ng of DNA in PCR reactions. Different concentrations of raw chicken were detected based on the threshold cycle. The technique was able to detect from 5% to 90% ratios of the chicken materials in sausages. Analysis of the experimental meat mixtures revealed the usefulness of the assays in detecting and quantifying chicken mitochondrial DNA in the mixtures.  相似文献   
183.
Polyomavirus (Py) derives its name from the early observation of multiple tumors that develop in newborn mice following inoculation with this family of viruses. In nature, however, tumor development is rare in the virus life cycle, rather a two-phase infection occurs, acute and persistent, resulting in a final latent infection in the kidneys. The acute phase induces an antiviral immune response, although no recognizable inflammation, which can last the lifetime of the mouse, even passing on antibodies to its offspring. The structure, replication, and expression of the Py viral genome in permissive and nonpermissive infections has been studied extensively in various cell culture systems. However, the nature of Py expression, replication, and immunopathogenesis in mice has not been thoroughly researched.  相似文献   
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185.
This paper provides an overview of existing approaches to encoding information on DNA strands for biocomputing, with a focus on the notion of Watson–Crick (WK) palindromes. We obtain a closed form for, as well as several properties of WK palindromes: The set of WK-palindromes is dense, context-free, but not regular, and is in general not closed under catenation and insertion. We obtain some properties that link the WK palindromes to classical notions such as that of primitive words. For example we show that the set of WK-palindromic words that cannot be written as the product of two nonempty WK-palindromes equals the set of primitive WK-palindromes. We also investigate various simultaneous Watson–Crick conjugate equations of words and show that the equations have, in most cases, only Watson–Crick palindromic solutions. Our results hold for more general functions, such as arbitrary morphic and antimorphic involutions.  相似文献   
186.
Cinnamon has a long history of medicinal use and continues to be valued for its therapeutic potential for improving metabolic disorders such as type 2 diabetes. In this study, a phytochemically-enhanced functional food ingredient that captures water soluble polyphenols from aqueous cinnamon extract (CE) onto a protein rich matrix was developed. CE and cinnamon polyphenol-enriched defatted soy flour (CDSF) were effective in acutely lowering fasting blood glucose levels in diet induced obese hyperglycemic mice at 300 and 600 mg/kg, respectively. To determine mechanisms of action, rat hepatoma cells were treated with CE and eluates of CDSF at a range of 1–25 μg/ml. CE and eluates of CDSF demonstrated dose-dependent inhibition of hepatic glucose production with significant levels of inhibition at 25 μg/ml. Furthermore, CE decreased the gene expression of two major regulators of hepatic gluconeogenesis, phosphoenolpyruvate carboxykinase and glucose-6-phosphatase. The hypoglycemic and insulin-like effects of CE and CDSF may help to ameliorate type 2 diabetes conditions.  相似文献   
187.
Spectroscopic characterisation of γ-LiAlO2 composite polymeric electrolytes based on poly-(ethylene oxide)(PEO)/perfluorinated polyphosphazene blends and LiPF6 as electrolyte was studied by means of FTIR and X-ray spectroscopy. Ionic conductivity was analysed by using complex impedance. A parallel study was made on samples containing propylene carbonate as plasticizer instead of γ-LiAlO2. The results obtained indicate, in a first approximation, that there is a drastic change in PEO morphology resulting from the co-ordination with the lithium salt and, at the same time, that the morphology of the composite polymer electrolytes is dependent on the nature of the polymer host. Complex impedance data show that the incorporation of γ-LiAlO2 enhances the ionic conductivity of the composite polymer electrolyte, a reverse behaviour is found for the composite systems plasticized with PC.  相似文献   
188.
Morphological properties of composite polymer electrolytes based on blends of polyethylene oxide (PEO) and a perfluorinated polyphosphazene (PPz) containing LiPF6 as lithium salt and a finely divided ceramic filler, γ-LiAlO2, were studied by using polarizing optical microscopy and differential scanning calorimetry (DSC). A parallel study was performed on propylene carbonate plasticized composite polymer electrolytes. Results indicate that both the morphology and the thermal properties depend upon the composition of the polymer host, a result not observed in composite polymer electrolytes having the same polymer composition containing LiCF3SO3 as lithium salt. The incorporation of the ceramic filler at the lower concentration tested (10% by wt) has practically no effect on the thermal behavior of the samples; whereas, differences were clearly distinguished at a concentration of ceramic material of 20 wt %. © 1999 John Wiley & Sons, Inc. J Appl Polym Sci 73: 1023–1030, 1999  相似文献   
189.
Although making up only 9% of the U.S. population and concentrated in urban areas of a few states, Hispanics are found throughout the country and represent a mix of historical and cultural backgrounds. This diverse group cuts across racial and ethnic lines, with origins in various countries of Europe and North, Central, and South America. The Hispanic population has several distinguishing demographic characteristics, including its rapid growth rate, relative youth, and low educational and socioeconomic levels. However, considerable differences exist among Hispanic groups, particularly in median age, household size, education, and family income. The majority of Hispanics face barriers to health care access, including a lack of health insurance coverage, underrepresentation in health care fields, and cultural and language differences. These distinct demographic characteristics and barriers have a direct impact on the risk of cancer in Hispanics and on the development of prevention and control strategies. The purpose of this review is to examine the demographic and socioeconomic characteristics of Hispanics and issues of access to health care among this population within the context of cancer prevention and control.  相似文献   
190.
Measurement of bioimpedance (BI) is a simple non-invasive technique that relies on the different conductivity of tissues to define body composition and can be easily adapted to automated monitoring. We assessed the accuracy of BI in monitoring rehydration and acute fluid fluxes in 35 Peruvian cholera patients. Patients were monitored throughout the acute phase of diarrhoea and followed up at 3 and 10 days. BI was compared with other objective measures of dehydration including packed cell volume, serum protein, and calculated fluid balance. BI rapidly detected inadequate treatment and acute fluid flux, correlating highly with intravascular hydration as measured by serum protein and packed cell volume. BI values during dehydration were significantly raised compared with 10-day convalescent values and age-matched controls (p < 0.05). We also encountered an unexpected difference in the bioelectrical response to dehydration and rehydration between sexes. We conclude that BI has uses in monitoring dehydrated patients, in oral rehydration trials, and in physiological studies.  相似文献   
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