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941.
Diverse proteins of the denegerin/epithelial sodium channel (DEG/ENa+C) superfamily, in particular those belonging to the acid‐sensing ion channel (ASIC) family, as well as some members of the transient receptor protein (TRP) channel, function as mechanosensors or may be required for mechanosensation in a diverse range of species and cell types. Therefore, we investigated the putative mechanosensitive function of human odontoblasts using immunohistochemistry to detect ENa+C subunits (α, β, and γ) and ASIC (1, 2, 3, and 4) proteins, as well as TRPV4, in these cells. Positive and specific immunoreactivity in the odontoblast soma and/or processes was detected for all proteins studied except α‐ENa+C. The intensity of immunostaining was high for β‐ENa+C and ASIC2, whereas it was low for ASIC1, ASIC3, γ‐ENa+C, and TRPV4, being absent for α‐ENa+C and ASIC4. These results suggest that human odontoblasts in situ express proteins related to mechanosensitive channels that probably participate in the mechanisms involved in teeth sensory transmission. Microsc. Res. Tech., 2011. © 2010 Wiley‐Liss, Inc.  相似文献   
942.
Orduña-Malea  Enrique 《Scientometrics》2020,123(3):1317-1340
Scientometrics - The main objective of this work is to analyse the contributions of Judit Bar-Ilan to the search engines studies. To do this, two complementary approaches have been carried out....  相似文献   
943.
The aim of this study was to determine the antibacterial activity in vitro of Melipona and Apis honey against various foodborne microorganisms. The results of qualitative test showed that Melipona honey inhibited both Staphylococcus aureus ATCC25923 and H08M06 strains and both Escherichia coli ATCC35922 and H12K06 strains. Apis honey inhibited both E. coli ATCC35922 and H12K06 strains and S. aureus ATCC25923 strain. Minimum inhibitory concentrations of Melipona honey (5–16%, w/v) were lower than those of Apis honey (15–31%, w/v). This study demonstrated that the antibacterial potency of Melipona honey could be a new alternative for controlling foodborne illness.  相似文献   
944.
The existence of a range of optimal coefficient of friction that encompasses safety and comfort has not been addressed before. This paper assesses the existence of such a range and its relationship with the variability of human gait. Six women walked for 15 min over five ceramic tile floorings with friction coefficients (DCOF) ranging from 0.19 to 0.63. Subjective opinions (pain, comfort, etc.) and biomechanical parameters including sagittal plane knee angle, tibia acceleration, and ground reaction forces were gathered. The required coefficient of friction (RCOF) was calculated from ground reaction forces. The results show that as DCOF increases so do reports of pain in the knees and under the metatarsal heads and toes; whereas a low DCOF relates to pain in the thighs and perception of low friction. RCOF showed a quadratic relationship with DCOF indicating the existence of a range of optimal coefficient of friction outside of which walking strategy is modified either to avoid slipping (DCOF < 0.25) or reduce pain (DCOF > 0.55). This result is supported by the results of the analysis of gait variability using non-linear methods. Floors inside the optimal range of friction yielded statistically significant higher entropy for tibia acceleration and knee angle, confirming the hypothesis that gait is more constrained outside that range (i.e. natural variability is reduced).Relevance to the industry: Floor friction is one of the main concerns for the floor industry and for decision makers when choosing public space paving (indoor and outdoor). The false concept ‘the more friction the better’ can induce manufacturers and technicians to make wrong decisions. This paper can assist the industry produce and select solutions encompassing safety and comfort.  相似文献   
945.
压电换能器用于NDE(非破坏性评估)应用。PVDF(聚偏氟乙烯)换能器有很多优点.包括大带宽和高灵敏度。这些换能器需要高电压和大带宽的放大器。图1中的电路源于往期的一个设计实例(参考文献1)。电路的工作原理基本相同,但本设计可以在高至500kHz频率下驱动一个2.3nF的容性负载。  相似文献   
946.
Artificial vision systems are powerful tools for the automatic inspection of fruits and vegetables. Typical target applications of such systems include grading, quality estimation from external parameters or internal features, monitoring of fruit processes during storage or evaluation of experimental treatments. The capabilities of an artificial vision system go beyond the limited human capacity to evaluate long-term processes objectively or to appreciate events that take place outside the visible electromagnetic spectrum. Use of the ultraviolet or near-infrared spectra makes it possible to explore defects or features that the human eye is unable to see. Hyperspectral systems provide information about individual components or damage that can be perceived only at particular wavelengths and can be used as a tool to develop new computer vision systems adapted to particular objectives. In-line grading systems allow huge amounts of fruit or vegetables to be inspected individually and provide statistics about the batch. In general, artificial systems not only substitute human inspection but also improve on its capabilities. This work presents the latest developments in the application of this technology to the inspection of the internal and external quality of fruits and vegetables.  相似文献   
947.
Although considered a rare retinal dystrophy, retinitis pigmentosa (RP) is the primary cause of hereditary blindness. Given its diverse genetic etiology (>3000 mutations in >60 genes), there is an urgent need for novel treatments that target common features of the disease. TLR2 is a key activator of innate immune response. To examine its role in RP progression we characterized the expression profile of Tlr2 and its adaptor molecules and the consequences of Tlr2 deletion in two genetically distinct models of RP: Pde6brd10/rd10 (rd10) and RhoP23H/+ (P23H/+) mice. In both models, expression levels of Tlr2 and its adaptor molecules increased in parallel with those of the proinflammatory cytokine Il1b. In rd10 mice, deletion of a single Tlr2 allele had no effect on visual function, as evaluated by electroretinography. However, in both RP models, complete elimination of Tlr2 attenuated the loss of visual function and mitigated the loss of photoreceptor cell numbers. In Tlr2 null rd10 mice, we observed decreases in the total number of microglial cells, assessed by flow cytometry, and in the number of microglia infiltrating the photoreceptor layers. Together, these results point to TLR2 as a mutation-independent therapeutic target for RP.  相似文献   
948.
Progression through the cell division cycle is controlled by a family of cyclin‐dependent kinases (CDKs), the activity of which depends on their binding to regulatory partners (cyclins A–H). Deregulation of the activity of CDKs has been associated with the development of infectious, neurodegenerative, and proliferative diseases such as Alzheimer's, Parkinson's, or cancer. Most cancer cells contain mutations in the pathways that control the activity of CDKs. This observation led this kinase family to become a central target for the development of new drugs for cancer therapy. A range of structurally diverse molecules has been shown to inhibit the activity of CDKs through their activity as ATP antagonists. Nevertheless, the ATP binding sites on CDKs are highly conserved, limiting the kinase specificity of these inhibitors. Various genetic and crystallographic approaches have provided essential information about the mechanism of formation and activation of CDK–cyclin complexes, providing new ways to implement novel research strategies toward the discovery of new, more effective and selective drugs. Herein we review the progress made in the development of ATP‐noncompetitive CDK–cyclin inhibitors.  相似文献   
949.
Cells in the balance : Programmed cell death is an important and stringently controlled process. Aberrancies in its control mechanisms can lead to disease; overactive apoptosis can cause neurodegenerative disorders, whereas deficient apoptotic activity can lead to cancer. Therefore, controlling apoptotic pathways with peptides is showing increasing promise as a strategy in drug development.

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950.
Dense samples of Ce0.9Gd0.1O2δ with grain sizes in the range 91–252 nm were prepared and their electrical properties studied by impedance spectroscopy. It was found that the bulk conductivity is not affected by grain size or atmosphere and that small grain sizes lead to a larger total resistance of the material. The most striking result corresponds to a sample sintered in wet air that exhibited electrical characteristics that hint clearly at the presence of proton conduction at temperatures below 200 °C.  相似文献   
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