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991.
992.
A website was designed in order to help patients with chronic lower back pain (cLBP) to cope with their condition, relying on the concept of health literacy. A sample of 748 chronic or potentially chronic LBP patients were asked to regularly visit the site for a period of 12 months. The intervention was evaluated quantitatively (both preuse and postuse surveys, logfiles) and qualitatively. Users appear to have taken less painkillers than before in the period they accessed the site. Most users reported that the site contributed to increasing their knowledge, and helped them managing their back pain. Communication with doctors, family, and colleagues improved. Qualitative evaluation showed several positive effects including self‐comprehension, improvement of argumentative abilities, orientation, and self‐confidence.  相似文献   
993.
Almost all tumors are composed of a heterogeneous cell population, making them difficult to treat. A small cancer stem cell population with a low proliferation rate and a high tumorigenic potential is thought to be responsible for cancer development, metastasis and resistance to therapy. Stem cells were reported to be involved in both normal development and carcinogenesis, some molecular mechanisms being common in both processes. No less controversial, stem cells are considered to be important in treatment of malignant diseases both as targets and drug carriers. The efforts to understand the role of different signalling in cancer stem cells requires in depth knowledge about the mechanisms that control their self-renewal, differentiation and malignant potential. The aim of this paper is to discuss insights into cancer stem cells historical background and to provide a brief review of the new therapeutic strategies for targeting cancer stem cells.  相似文献   
994.
995.
Fractionated high pressure extractions from dry and in natura elderberry pomace were performed in order to obtain anthocyanin rich extracts. Experiments were carried out using CO2 supercritical fluid extraction followed by enhanced solvent extraction (ESE) with CO2/EtOH–H2O mixtures (1–100%, v/v), to obtain anthocyanin rich fractions in the second step, at 313 K and ~20 MPa. Higher extract yields, anthocyanin contents and antioxidant activities occurred by the presence of water, both in the raw material and in the solvent mixture. The CO2 dissolved in the ESE solvent mixture favored either anthocyanin contents or antioxidant activities, which were not directly related. Comparing to the literature data for elderberries and grapes, these fractions had higher anthocyanins contents. From these results, an added economical value to this agroindustrial residue is proposed, using solvents and techniques “generally regarded as safe” in the food and pharmaceutical industries.  相似文献   
996.
997.
For many years the introduction of Electronic Health Records (EHRs) in medical practice has been considered the best way to provide efficient document sharing among different organizational settings. The actual results of these technologies, though, do not seem to have matched expectations. The issue of document sharing has been lately readdressed by proposing the creation of patient-controlled information and communication technologies, Personal Health Records (PHRs), providing laypeople the tools to access, manage and share their health information electronically by connecting to the existing EHRs and other institutional information systems. In this scenario, patients are called to play a major role in coordinating healthcare professionals by providing them the information they need. From a CSCW perspective the PHR offers an interesting case to reflect on cooperative work that requires new infrastructures that intersect organizational settings and extend into domestic environments. So far though, there has not been enough research to shed light on the self-care activities carried out in the households and how these integrate with the organizational practices of doctors and institutions. Our analyses show that health record keeping is an articulation work necessary for meetings with doctors to proceed smoothly. To do so, people integrate the information contained in medical documents by working on them with annotations, underlinings and integrations. Moreover, we show that health record keeping is a spatialized activity that is inextricably interwoven with the everyday routine and objects. Finally, we provide a tentative classification of three different strategies laypeople use to sort out health records: minimum effort, adaptive, networking.  相似文献   
998.
A simple strategy for the synthesis and functionalization of polyurethanes is described. Anionic ring‐opening polymerization was combined with ‘click’ chemistry to synthesize polyols with fluorescent properties. This route allows the incorporation of a wide range of functionalities in the polyols with an easy, clean and highly selective process compatible with several types of functional groups. The proposed strategy opens the way to the production, in a cost‐effective way, of ‘smart’ polyurethanes with non‐conventional properties like fire retardancy, antimite properties, antibacterial properties, etc. Alkynyl groups were introduced into the polyol chains by the controlled addition of glycidyl propargyl ether as co‐monomer during a conventional anionic ring‐opening copolymerization with propylene oxide. Subsequently 4‐azidomethyl‐7‐methoxycoumarin molecules were introduced onto the alkynyl‐polyether polyols by copper‐catalysed cycloaddition reactions to produce end‐functionalized polyols. The chemical structure of the novel polyols was characterized using infrared spectroscopy, nuclear magnetic resonance spectroscopy, gel permeation chromatography with triple detection and matrix‐assisted laser desorption/ionization time‐of‐flight mass spectroscopy. These characterization techniques confirmed the presence of a considerable amount of functional groups in the structure of the polyols. Finally, various fluorescent rigid foams, based on the functionalized polyols, were synthesized. Copyright © 2012 Society of Chemical Industry  相似文献   
999.
Dyes have been applied and are playing an increasingly important role in many industries, including the textile, printing, medical and energy industries. Their wide applications imply that specific dyes possessing given properties need to be effectively designed. The present review aims to survey information related to activity/property research of dyes that has been published in the past two decades. Emphasis is laid particularly on studies based on quantitative structure–activity/property relationships that have contributed to the theoretical design and application of dyes. Finally, the perspectives of quantitative structure‐activity/property relationship studies are set out in order to show how this method may be used to design new dyes and to evaluate their different properties. The challenges facing these studies are also outlined.  相似文献   
1000.
Hybrid organic–inorganic films were prepared using four different hydroxylated soybean oils (HSO) or epoxidized soybean oil as organic precursor and tetraethyl orthosilicate (TEOS) as inorganic precursor in a mass ratio of HSO:TEOS of 90:10. The films were macroscopically homogeneous and were characterized by swelling and extraction in solvent, thermogravimetric analysis (TGA), scanning electron microscopy (SEM) including energy dispersive spectroscopy (EDX), adhesion and hardness. Their properties varied as a function of the number of OH groups present in the HSO. The best hybrid system was HSOF198/TEOS, with an OH value of 198 mg of KOH/g, which presents lower swelling coefficient, very good adhesion on aluminium surface and good hardness.  相似文献   
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