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11.
Objectives: To examine the power of the combined measurements of body mass index (BMI) and waist circumference (WC) for the prediction of abnormality in coronary heart disease risk factors and to determine whether the additional measurement of WC is predictive in older men and women. Research Methods and Procedures: 1190 men and 751 women of the Baltimore Longitudinal Study of Aging were dichotomized into younger (<65 years) and older (65+ years) age groups. Coronary risk factors in the realms of glucose/insulin metabolism, blood pressure, and plasma lipids were assessed. The relationship of BMI and WC, singly and combined, to 10 risk factors for coronary heart disease was examined. Results: In younger and older men and women, BMI and WC are highly correlated (0.84 to 0.88). BMI and WC are also significantly correlated to all 10 coronary risk factors in younger men and women and to 8 of the 10 in the older men and women. Both partial correlation and logistic regression analyses revealed a modest but significant improvement in the prediction of coronary risk in younger men and women by WC after controlling for the level of BMI. There was no improvement in the older subjects. Discussion: WC adds only modestly to the prediction of coronary risk in younger subjects once BMI is known, and adds nothing to the production of risk in older subjects.  相似文献   
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This study was conducted to evaluate and compare the effectiveness of two organic amendments [poultry manure (PM) and poultry manure biochar (PMB)] for the degradation of petroleum hydrocarbons in contaminated soils by barley plant at three levels of total petroleum hydrocarbons (TPHs) during 5 months under greenhouse conditions. TPHs removal efficiency and microbial respiration were shown to be higher at soil-cultivated plant than at uncultivated soil and in lowest level of contamination rather than other levels of contamination and at organic amendment treatment than unamended soil. Soil microbial respiration and TPHs degradation in the rhizosphere of barley increased by 15.64 and 12.74% for PM-amended treatment and 28.07 and 26.83% for PMB-amended treatment, respectively, in the 4% TPHs level compared with unamended treatment. Comparison of two amendments showed that in PMB treatment soil, highest dry weight, microbial respiration, and TPHs degradation potential were observed.  相似文献   
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LiF:Mg,Cu,Ag is a new dosimetry material that is similar to LiF:Mg,Cu,P in terms of dosimetric properties. The effect of the annealing temperature in the range of 200 to 350°C on the thermoluminescence (TL) sensitivity and the glow curve structure of this material at different concentrations of silver (Ag) was investigated. It has been demonstrated that the optimum values of the annealing temperature and the Ag concentration are 240°C and 0.1 mol% for better sensitivity, respectively. The TL intensity decreases at annealing temperatures lower than 240°C or higher than 240°C, reaching a minimum at 300°C and then again increases for various Ag concentrations. It was observed that the glow curve structure altered and the area under the low temperature peak as well as the area under the main dosimetric peak decreased with increasing annealing temperature. The position of the main dosimetric peak moved in the direction of higher temperatures, but at 320 and 350°C annealing temperatures, it shifted to lower temperatures. It was also observed that the TL sensitivity could partially be recovered by a combined annealing procedure.  相似文献   
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The fine structural characteristics and phagocytic properties of peroxidase-positive and peroxidase-negative cells in rat hepatic sinusoids were investigated. Cells with a positive peroxidase reaction in the endoplasmic reticulum and the nuclear envelope make up approximately 40% of cells in rat hepatic sinusoids and have abundant cytoplasm containing numerous granules and vacuoles, and occasional tubular, vermiform invaginations. After intravenous injection of colloidal carbon, the luminal plasma membrane of these cells shows continuous sticking of carbon, and there is evidence of avid phagocytosis of colloidal carbon particles. Peroxidase-positive cells are the only cells in hepatic sinusoids which phagocytize large (0.8 µ in diameter) latex particles. In contrast, the peroxidase-negative endothelial cells, which make up 48% of cells, have scanty perinuclear cytoplasm and organelles, and their long cytoplasmic extensions that form the lining of the hepatic sinusoids have fenestrations; these cells ingest small amounts of colloidal carbon, principally by micropinocytosis, exhibit no sticking of carbon particles to their plasma membranes, and do not ingest the larger (latex) particles. The so-called fat-storing cells are peroxidase negative and totally nonphagocytic. The peroxidase reaction thus distinguishes the typical mononuclear phagocytes or Kupffer cells of rat liver from the endothelial-lining cells.  相似文献   
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Erythropoietin (EPO) is the principal hormone which, has somewhat short half-life involved in the differentiation and regulation of circulating red blood cells. The present study was carried out to evaluate the capability of a polyethylene glycol mimetic technology as a biological alternative to improve pharmaceutical properties of human recombinant EPO. In silico models of EPO fused to 200 amino acids of proline, alanine, and serine (PAS) were initially generated and assessed by molecular dynamic (MD) simulation. The fluctuations of the modeled structure reached a plateau after 6000 ps of MD simulation. The Phi and psi analysis showed >99.2% of residues were located in the allowed regions. An expression vector consisting of EPO cDNA tagged to PAS coding sequences was synthesized and expressed in CHO-K1 Cells. The produced PASylated molecule was purified and characterized by standard analytical methods. The molecular weight of fusion protein was expanded to 70 kDa using sodium dodecyl sulfate polyacrylamide gel electrophoresis method. Analytical size exclusion chromatography revealed an approximately sevenfold increase in apparent size of produced protein. Although the in vitro potency of the fusion protein was significantly reduced (1.26?±?0.05 vs. 0.24?±?0.03 ng/ml) but, the in vivo activity was considerably increased up to 1.58?×?105 IU/ml in normocythemic mice assay. Pharmacokinetic animal studies revealed strongly 15.6-fold plasma half-life extension for the PASylated EPO (83.16?±?13.28 h) in comparison to epoetin α (8.5?±?2.4 h) and darbepoetin α (25.3?±?2.2h).  相似文献   
18.
The historical circumstances that led to the discovery of the 3,3′-diamino-benzidine (DAB) method for staining of peroxisomes 40 years ago are reviewed. In the course of studies on the uptake and absorption of horse radish peroxidase in mammalian liver, in sections incubated for detection of peroxidase activity in DAB, it was noted that peroxisomes also stained positively for peroxidase activity. Subsequently, it was revealed that the peroxidatic activity of catalase, which is abundantly present in peroxisomes, is responsible for that staining. This notion was confirmed in quantitative biochemical studies with crystalline beef liver catalase and in tracer studies using catalase as an ultrastructural tracer. The application of the DAB method led to the discovery of peroxisomes as a ubiquitous eukaryotic cell organelle, attracting great interest in their investigation in biomedical research.  相似文献   
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Neisseria meningitidis is efficiently phagocytosed by polymorphonuclear leukocytes (PMNS) following opsonization with opsonic antibodies; opsonophagocytosis is the primary mechanism for clearance of meningococci from the host. Thus, in testing meningococcal vaccines, the level of opsonophagocytic antibodies appears to correlate with vaccine-induced protection. Our previous studies demonstrated that the conjugation ofN. meningitidis serogroup A capsular polysaccharide (CPSA) to serogroup B outer membrane vesicle (OMV) could induce a high level of bactericidal antibody response against serogroup A meningococci in animals. The purpose of this study was to evaluate opsonophagocytic activity of the conjugate of CPSA to OMV (CPSA-OMV). In order to evaluate the potential efficacy of CPSA-OMV a flow cytometric opsonophagocytic assay was used. The conjugate and controls were injected intramuscularly into four groups of rabbits with boosters on days 14, 28 and 42 following primary immunization. The rabbits were bled prior to injection and two weeks after each injection. Opsonophagocytic activity of antibodies in hyperimmune sera through rabbit PMNS were measured with flow cytometer, using dihydrorhodamine-123 as a probe. The results indicated that our conjugate could induce a highly significant level of opsonophagocytic activity against serogroup A meningococci after 56 days compared to the control groups (P<0.05). We conclude that this conjugate represents a vaccine candidate against serogroups A and B meningococci after further investigation.  相似文献   
20.
Genomic amplification of 19q12 occurs in several cancer types including ovarian cancer where it is associated with primary treatment failure. We systematically attenuated expression of genes within the minimally defined 19q12 region in ovarian cell lines using short-interfering RNAs (siRNA) to identify driver oncogene(s) within the amplicon. Knockdown of CCNE1 resulted in G1/S phase arrest, reduced cell viability and apoptosis only in amplification-carrying cells. Although CCNE1 knockdown increased cisplatin resistance in short-term assays, clonogenic survival was inhibited after treatment. Gain of 20q11 was highly correlated with 19q12 amplification and spanned a 2.5 Mb region including TPX2, a centromeric protein required for mitotic spindle function. Expression of TPX2 was highly correlated with gene amplification and with CCNE1 expression in primary tumors. siRNA inhibition of TPX2 reduced cell viability but this effect was not amplicon-dependent. These findings demonstrate that CCNE1 is a key driver in the 19q12 amplicon required for survival and clonogenicity in cells with locus amplification. Co-amplification at 19q12 and 20q11 implies the presence of a cooperative mutational network. These observations have implications for the application of targeted therapies in CCNE1 dependent ovarian cancers.  相似文献   
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