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There is a pressing need to develop more effective therapeutics to fight cancer. An idyllic chemotherapeutic is expected to overcome drug resistance of tumors and minimize harmful side effects to healthy tissues. Antibody‐functionalized porous silicon nanoparticles loaded with a combination of chemotherapy drug and gold nanoclusters (AuNCs) are developed. These nanocarriers are observed to selectively deliver both payloads, the chemotherapy drug and AuNCs, to human B cells. The accumulation of AuNCs to target cells and subsequent exposure to an external electromagnetic field in the microwave region render them more susceptible to the codelivered drug. This approach represents a targeted two‐stage delivery nanocarrier that benefits from a dual therapeutic action that results in enhanced cytotoxicity.  相似文献   
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The Journal of Supercomputing - A multimedia-based medical decision-making system is an ultimate requirement in the medical imaging domain. In the healthcare sector, achieving quick and efficient...  相似文献   
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During recent years, accumulating evidence suggested that metal-based candidate drugs are promising modulators of cytoskeletal and cytoskeleton-associated proteins. This was substantiated by the identification and validation of actin, vimentin and plectin as targets of distinct ruthenium(II)- and platinum(II)-based modulators. Despite this, structural information about molecular interaction is scarcely available. Here, we compile the scattered reports about metal-based candidate molecules that influence the cytoskeleton, its associated proteins and explore their potential to interfere in cancer-related processes, including proliferation, invasion and the epithelial-to-mesenchymal transition. Advances in this field depend crucially on determining binding sites and on gaining comprehensive insight into molecular drug-target interactions. These are key steps towards establishing yet elusive structure-activity relationships.  相似文献   
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In this work, the effective elastic moduli of two-phase fibrous periodic composites are obtained by means of the Asymptotic Homogenization Method (AHM) and eigenfunction expansion-variational method (EEVM), for different types of parallelogram cells. The constituents exhibit transversely isotropic properties. A doubly periodic parallelogram array of cylindrical inclusions under longitudinal shear is considered. The behavior of the shear elastic coefficient for different geometry arrays of the cell related to the angle of the fibers is studied. Some numerical examples and comparisons with other theoretical results demonstrate that both methods (AHM and EEVM) are efficients for the analysis of composites with presence of rhombic cell. The effect of the configuration of the cells on the shear effective property is observed.  相似文献   
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A solid state reaction method was used to synthesize barium titanate (BT) and barium cerium titanate (BCT) ceramics at sintering temperature of 1473 K for 4 h. The effect of cerium (Ce) on the structure, microstructure and dielectric properties of BCT was investigated. The scanning electron microscopy (SEM) investigations revealed that the grain size increases with increasing Ce content. The X-ray diffraction (XRD) patterns showed mostly the BT phase, where the lattice parameter decreased with the addition of Ce. The temperature dependence of dielectric constant showed decrease in the phase transition temperature with higher Ce content. The dielectric constant decreased slightly with increasing frequency. The direct current (dc) density-voltage characteristics of the ceramics showed ohmic behavior for both the BT and BCT. As the temperature increased, the dc resistivity of the ceramics decreased. The activation energy increased with increasing Ce content.  相似文献   
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Colony counting by spreading bacterial suspensions on plating media by various techniques is of general concern. Comparative studies between hand plating (Drigalski-spatula technique) for different time intervals and spiral plating resulted in significant differences in colony counts. Lower counts of Gram-negative bacteria were obtained by using hand plating for more than 10 s, compared with short time hand plating (5 s) or spiral plating. Colony counting of Gram-positive bacteria showed no differences between both techniques. Further characterisation of Escherichia coli cells spread with the Drigalski-spatula technique by electron microscopy revealed a large number of damaged cells compared to control samples. The data clearly shows that the mechanical forces during hand plating are sufficient to damage E. coli cells.  相似文献   
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The authors examined the subtype structure of smokers classified in the precontemplation stage of change within the transtheoretical model. From a general practice-based sample of 1,499 daily smoking patients from Germany (participation rate 80%), they used a subgroup of 929 smokers who were classified in the precontemplation stage and applied latent class analysis, using the pros and cons of nonsmoking and smoking cessation self-efficacy as the defining variables. Cross-sectional validation of the emerging classes was based on smoking behavior and processes of change variables. For longitudinal validation, generalized estimation equation analyses were used on motivational and abstinence criteria from 6-, 12-, 18-, and 24-month follow-ups. A 4-class model best represented the data. Three subtypes (labeled progressive, immotive, and disengaged pessimistic) were similar to clusters identified in U.S. studies. The 4th (disengaged optimistic), by contrast, was reminiscent of a type that had previously only emerged in a Dutch study. Cross-sectional and longitudinal validation results confirmed the distinctiveness and predictive power of the classes. The findings highlight the importance of tailoring interventions for smoking behavior change to the needs of different subgroups of precontemplating smokers. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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