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1.
Xanthohumol (XH) is an important prenylated flavonoid that is found within the inflorescence of Humulus lupulus L. (Hop plant). XH is an important ingredient in beer and is considered a significant bioactive agent due to its diverse medicinal applications, which include anti-inflammatory, antimicrobial, antioxidant, immunomodulatory, antiviral, antifungal, antigenotoxic, antiangiogenic, and antimalarial effects as well as strong anticancer activity towards various types of cancer cells. XH acts as a wide ranging chemopreventive and anticancer agent, and its isomer, 8-prenylnaringenin, is a phytoestrogen with strong estrogenic activity. The present review focuses on the bioactivity of XH on various types of cancers and its pharmacokinetics. In this paper, we first highlight, in brief, the history and use of hops and then the chemistry and structure–activity relationship of XH. Lastly, we focus on its prominent effects and mechanisms of action on various cancers and its possible use in cancer prevention and treatment. Considering the limited number of available reviews on this subject, our goal is to provide a complete and detailed understanding of the anticancer effects of XH against different cancers.  相似文献   
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Studying peripheral blood mononuclear cells (PBMCs) has become an important diagnostic tool in lysosomal storage diseases. Previous studies revealed that B and subclasses of T lymphocytes participate in the storage process, whereas the role of circulating monocytes was not clear. In this study, the involvement of CD14+ monocytes in lysosomal diseases was investigated. Blood samples from six patients with different lysosomal storage disorders were studied, including one with late--infantile and three with juvenile neuronal ceroid--lipofuscinoses, and two with mucopolysaccharidosis type VI. CD14+ cells were separated immunomagnetically from PBMCs and studied by light and electron microscopy. In all investigated disorders, disease-specific lysosomal storage material could be found in monocytes. The ratio of affected to non-affected cells did not differ from previously reported data on lymphocytes and their subforms in these diseases. Our data were obtained by studying a small number of different lysosomal storage disorders. Nevertheless, they suggest that lysosomal storage in the monocyte-macrophage system might also be found in other forms of lysosomal diseases.  相似文献   
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Samples of {4-(dimethylamino) stilben Z & E 4'-yl} dimesityl borane (BNS) were synthesised and investigated for their non-linear optical properties. The results show that the quadratic hyperpolarisability of the Z-isomer is smaller than that of the E-isomer, the beta value found for the latter being as high as 60 × 10?30 esu.  相似文献   
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Investigated the relationship between Type A (coronary prone) behavior, aerobic fitness, and cardiovascular recovery from stress in 56 male undergraduates. Ss were tested for actual aerobic power and Type A behavior on the Jenkins Activity Survey—Form T before performing the Stroop Color–Word Interference Test. Type A behavior was related to speed of recovery following the test, with Type As being slower to return to baseline heart rate levels than Type B (noncoronary prone) Ss. Physiological and cognitive variables affecting speed of recovery from stress are examined, and the lack of effect of fitness on recovery is discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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Rheological behaviour of polysaccharide aqueous solutions   总被引:1,自引:0,他引:1  
Several data relative to the viscosity of water-soluble polysaccharide solutions were collected from the literature and processed by different rheological models. Some relationships between the viscosity of these polymer solutions, their molecular weight and their solution concentrations, were established and their validity checked. Thus, an accurate equation correlating the viscosity and both the shear rate and the solution concentration of different water soluble polysaccharides (xanthan, hyaluronan, carboxymethylcellulose) was deduced on the basis of Cross' model which suggests two domains in which the viscosity is constant, i.e. very low and very high shear rate ranges. Then, an expression relating the zero-shear viscosity (A) and the concentration of their solutions was proposed. Finally, an alternative equation to that of Mark–Houwink correlating the molecular weight and the intrinsic viscosity of the water-soluble polysaccharides studied in this paper was found.  相似文献   
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When students use computers as learning tools, the whole process of learning, and, indeed, the learners themselves, are transformed. This article illustrates some techniques that foster transformative learning in computer-assisted first-year literature classes: first, a lesson plan on A Valediction: Forbidding Mourning that uses Microsoft Word functions, including format painter, tables, and annotation to explore meaning in context; second, a plan for learners to use subconference options in the Daedalus Interactive Writing Environment to analyze Oedipus Rex; finally, a demonstration of how students engage in a meta-reflection process as they explore Barn Burning with Freelance Graphics.Marguerite Jamieson is an English instructor at Anne Arundel Community College in Arnold, Maryland, and a doctoral student at George Mason University. Her research interests include forming bridges between adult learning theory and contemporary literary theory — especially drawing on transformational learning theory and the work of Mikhail Bakhtin and Lev Vygotsky.Rebecca Kajs holds a doctorate in English from Texas Woman's University with a concentration in rhetoric. For ten years, she taught the use of heuristic tools for reading analysis at the University of Texas at Arlington. She is currently an associate professor of English and Philosophy at Anne Arundel Community College.Anne Agee holds a doctorate in rhetoric from The Catholic University of America. A professor of English and formerly director of the Humanities Computer Center at Anne Arundel Community College, she is currently the college's Coordinator of Instructional Technology. Dr. Agee and Professor Jamieson have collaborated in a study of the learning environment in a computer classroom, the results of which were published in the Fall 1995 issue of Teaching/Learning Conversations. Dr. Agee has also published Using [Daedalus] InterChange as a Teachers' Journal in the Fall 1995 issue of Wings.  相似文献   
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We introduce Process Overview, a situation awareness characterisation of the knowledge derived from monitoring process plants. Process Overview is based on observational studies of process control work in the literature. The characterisation is applied to develop a query-based measure called the Process Overview Measure. The goal of the measure is to improve coupling between situation and awareness according to process plant properties and operator cognitive work. A companion article presents the empirical evaluation of the Process Overview Measure in a realistic process control setting. The Process Overview Measure demonstrated sensitivity and validity by revealing significant effects of experimental manipulations that corroborated with other empirical results. The measure also demonstrated adequate inter-rater reliability and practicality for measuring SA based on data collected by process experts.

Practitioner Summary: The Process Overview Measure is a query-based measure for assessing operator situation awareness from monitoring process plants in representative settings.  相似文献   

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