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21.
A novel electroanalytical approach is proposed here, and it is demonstrated with the direct and simultaneous determination of two unknowns: the concentration of redox sites and the apparent diffusion coefficient for charge propagation in a single crystal of dodecatungstophosphoric acid. This Keggin-type polyoxometalate serves as a model bulk redox conducting inorganic material for solid-state voltammetry. The system has been investigated using an ultramicrodisk working electrode in the absence of external liquid supporting electrolyte. The analytical method requires numerical solution of the combination of two equations in which the first one describes current (or charge) in a well-defined (either spherical or linear) diffusional regime and the second general equation describes chronoamperometric (or normal pulse voltammetric current) under mixed (linear-spherical) conditions. The iterative approach is based on successive approximations through calculation and minimizing the least-squares error function. The method is fairly universal, and in principle, it can be extended to the investigation of other bulk systems including sol-gel processed materials, redox melts, and solutions on condition that they are electroactive and well behaved, they contain redox centers at sufficiently high level, and a number of electrons for the redox reaction considered is known.  相似文献   
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The lipophilic and hydrophilic antioxidants were evaluated in eight plants: safflower (Carthamus tinctorius), viper’s bugloss (Echium vulgare), quince (Cydonia vulgaris), evening primrose (Oenothera biennis), rose mosqueta (Rosa affinis rubiginosa), black seed (Nigella sativa), sea buckthorn (Hippophae rhamnoides) and borage (Borago officinales). The highest amounts of tocopherols were contained in seeds of borage and sea buckthorn (66.9 mg/100 g and 45.9 mg/100 g, respectively). The sea buckthorn seed lipids had the highest amount of total sterols (10.4 mg/g of lipids). The predominant form was campesterol. Sitosterol was the major sterol in the lipids of other tested seeds. The content of phenolic compounds ranged from 736.5 mg/100 g dry matter (d.m.) (evening primrose) to 74.8 mg/100 g d.m. (safflower). The highest antioxidant activity, expressed in % scavenged DPPH· free radicals, was observed for evening primrose (91.2%), while the lowest for safflower (36.2%). The correlation coefficient between the level of phenolic compounds and antioxidant activity was 0.53.  相似文献   
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Recent findings on the molecular basis of ovarian cancer development and progression create new opportunities to develop anticancer medications that would affect specific metabolic pathways and decrease side systemic toxicity of conventional treatment. Among new possibilities for cancer chemoprevention, much attention is paid to curcumin—A broad-spectrum anticancer polyphenolic derivative extracted from the rhizome of Curcuma longa L. According to ClinicalTrials.gov at present there are no running pilot studies, which could assess possible therapeutic benefits from curcumin supplementation to patients with primary epithelial ovarian cancer. Therefore, the goal of this review was to evaluate potential preclinical properties of curcumin and its new analogues on the basis of in vivo and in vitro ovarian cancer studies. Curcumin and its different formulations have been shown to display multifunctional mechanisms of anticancer activity, not only in platinum-resistant primary epithelial ovarian cancer, but also in multidrug resistant cancer cells/xenografts models. Curcumin administered together with platinum-taxane chemotherapeutics have been reported to demonstrate synergistic effects, sensitize resistant cells to drugs, and decrease their biologically effective doses. An accumulating body of evidence suggests that curcumin, due to its long-term safety and an excellent profile of side effects should be considered as a beneficial support in ovarian cancer treatment strategies, especially in patients with platinum-resistant primary epithelial recurrent ovarian cancer or multidrug resistant disease. Although the prospect of curcumin and its formulations as anticancer agents in ovarian cancer treatment strategy appears to be challenging, and at the same time promising, there is a further need to evaluate its effectiveness in clinical studies.  相似文献   
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Despite advances in cancer diagnosis and treatment, ovarian cancer remains one of the most fatal cancer types. The development of targeted nanoparticle imaging probes and therapeutics offers promising approaches for early detection and effective treatment of ovarian cancer. In this study, HER‐2 targeted magnetic iron oxide nanoparticles (IONPs) are developed by conjugating a high affinity and small size HER‐2 affibody that is labeled with a unique near infrared dye (NIR‐830) to the nanoparticles. Using a clinically relevant orthotopic human ovarian tumor xenograft model, it is shown that HER‐2 targeted IONPs are selectively delivered into both primary and disseminated ovarian tumors, enabling non‐invasive optical and MR imaging of the tumors as small as 1 mm in the peritoneal cavity. It is determined that HER‐2 targeted delivery of the IONPs is essential for specific and sensitive imaging of the HER‐2 positive tumor since we are unable to detect the imaging signal in the tumors following systemic delivery of non‐targeted IONPs into the mice bearing HER‐2 positive SKOV3 tumors. Furthermore, imaging signals and the IONPs are not detected in HER‐2 low expressing OVCAR3 tumors after systemic delivery of HER‐2 targeted‐IONPs. Since HER‐2 is expressed in a high percentage of ovarian cancers, the HER‐2 targeted dual imaging modality IONPs have potential for the development of novel targeted imaging and therapeutic nanoparticles for ovarian cancer detection, targeted drug delivery, and image‐guided therapy and surgery.  相似文献   
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Zusammenfassung The importance of the Internet for job procurement is increasing for the reason that three quarters of the people in the employment age are online. On the other hand because ever more companies are publishing their job offers on the Web. However, due to the large number of openings published online it is almost impossible for job seekers and job portals to gain an overview of the entire employment market. Since job offers lack semantically meaningful annotations, the search and integration into databases are made highly difficult. Applying Semantic Web technologies to the e-recruitment process provides advantages for all participants in the market. In this paper we describe a method for analysing the domain-specific language of an application domain. We use this method to describe the e-recruitment process and the necessary ontologies for annotating job offers and job applications. In conclusion, we present the prototypical implementation of the scenario based on Semantic Web, especially semantic matching.  相似文献   
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Let wt be a wire in a combinational Boolean network. There may exist a wire wa such that when wa is added and wt is removed, the overall circuit functionality is unchanged. Redundancy-addition-and-removal (RAR) is an efficient technique to find such a wa. The idea is to add a redundant alternative wire wa to make the target wire wt redundant. However, as long as the addition of wa together with the removal of wt does not change the overall functionality of the circuit, wires that are added and removed do not necessarily need to be redundant. This raises a question about the existence of alternative wires. Why can one wire replace another wire in a combinational Boolean network? In this paper, we analyze theoretically the existence of alternative wires and model it as an error-cancellation problem. The two existing rewiring techniques, the redundancy-addition-and-removal and the global flow optimization, are unified under the proposed generalized model.  相似文献   
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