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201.
While the intercellular lipid structure of the stratum corneum (SC) plays an important role in the skin barrier function, the depth‐dependent profile of the intercellular lipids contributes decisively to deepen the understanding of the skin barrier function, drug penetration, development of skin diseases and their medication. The depth‐dependent profile of the lipids' chemico‐physical properties, such as the solid–fluid phase transition and the order–disorder transition, can exclusively be measured in human skin in vivo by means of confocal Raman microscopy. In the present paper, the lipid–keratin peak (2820–3030 cm−1) was investigated. The lipid‐related Raman peaks centered at 2850 cm−1 and 2880 cm−1 were deconvoluted using Gaussian functions and investigated for their depth‐dependent shape and positional changes. Different fitting procedures show that even an additional Gaussian function cannot be used to fully characterize the lipid's polymethylene chains around 2880 cm−1, which justifies the introduction of the sharpness of the peak centered near 2880 cm−1. The results show that the 2880 cm−1 peak sharpness might be used for determining the SC thickness. The concentration of the lipids with long‐chain carbon backbone (free fatty acids and ceramides) semi‐quantitatively decreases from 10 µm to 20 µm (SC thickness is 19.8 µm). The maximum position and broadness of the Gaussian peak centered at 2850 cm−1 show that near the surface and in the deeper layers of the SC, the state of the lipids is more fluid and disordered compared to the medium layers of the SC. Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   
202.
On the setting of the half-space we introduce the Schatten-Herz classes of Toeplitz operators and obtain characterizations for positive Toeplitz operators to belong to those classes. We also prove results concerning the boundedness and compactness of Toeplitz operators with Herz symbols. Such a study has been recently done on the ball. At a critical step of the proofs we employ a much simplified argument to extend the range of parameters for Herz spaces on which the Berezin transform is bounded. Our results show not only that most of results on the ball continue to hold, but also that there is some pathology caused by the unboundedness of the domain. The first author was in part supported by a Korea University Grant(2007), the second author was in part supported by Hanshin University Research Grant, and both authors were in part supported by KOSEF(R01-2003-000-10243-0).  相似文献   
203.
Combinatorial selection of peptides that bind technological materials has emerged as a valuable tool for room-temperature nucleation and assembly of complex nanostructured materials. At present, the parameters that control peptide-solid binding are poorly understood, but such knowledge is needed to build the next generation of hybrid materials. Here, we use a derivative of the DNA binding protein TraI engineered with a disulfide-bonded cuprous oxide binding sequence called CN225 to probe the influence of sequence composition and conformation on Cu2O binding affinity. We previously reported a statistically significant enrichment in paired arginines (RR) among a family of cuprous oxide binding peptides and hypothesized that this is a key motif for binding. However, systematic alanine (A) substitutions in the CN225 RR motif (creating RA, AR, and AA pairs) do not support the hypothesis that RR is critical for Cu2O binding by CN225. Instead, we find that the presentation of the peptide in a disulfide-constrained loop (i.e., the conformation present during combinatorial selection) is crucial for binding to the metal oxide. Our results suggest that caution should be exerted when extrapolating from statistical data and that, in some cases, conformation is more important than composition in determining peptide-inorganic adhesion.  相似文献   
204.
Reactive oxygen species (ROS) play an important role in the pathogenesis of airway inflammation and hyperresponsiveness. Recent studies have demonstrated that antioxidants are able to reduce airway inflammation and hyperreactivity in animal models of allergic airway disease. A newly developed antioxidant, small molecular weight thiol compound, N-acetylcysteine amide (AD4) has been shown to increase cellular levels of glutathione and to attenuate oxidative stress related disorders such as Alzheimer's disease, Parkinson's disease, and multiple sclerosis. However, the effects of AD4 on allergic airway disease such as asthma are unknown. We used ovalbumin (OVA)-inhaled mice to evaluate the role of AD4 in allergic airway disease. In this study with OVA-inhaled mice, the increased ROS generation, the increased levels of Th2 cytokines and VEGF, the increased vascular permeability, the increased mucus production, and the increased airway resistance in the lungs were significantly reduced by the administration of AD4. We also found that the administration of AD4 decreased the increases of the NF-kappaB and hypoxia-inducible factor-1alpha (HIF-1alpha) levels in nuclear protein extracts of lung tissues after OVA inhalation. These results suggest that AD4 attenuates airway inflammation and hyperresponsiveness by regulating activation of NF-kappaB and HIF-1alpha as well as reducing ROS generation in allergic airway disease.  相似文献   
205.
206.
Molecular relaxation behavior in terms of the α, β, and γ transitions of miscible PS/PPO blends has been studied by means of DMTA and preliminary work has been carried out using DSC. From DSC and DMTA (by tan δ), the observed α relaxation (Tα or Tg) of PS, PPO, and the blends, which are intermediate between the constituents, are in good agreement with earlier reports by others. In addition, the β transition (Tβ) of PS at 0.03 Hz and 1 Hz is observed at −30 and 20°C, respectively, while the γ relaxation (Tγ) is not observed at either frequency. The Tβ of PPO is 30°C at 0.03 Hz and is not observed at 1 Hz, while the Tγ is −85°C at 0.03 Hz and −70°C at 1 Hz. On the other hand, blend composition-independent β or γ relaxation observed in the blends may be a consequence of the absence of intra- or intermolecular interaction between the constituents at low temperature. Thus it is suggested that at low temperature, the β relaxation of PS be influenced solely by the local motion of the phenylene ring, and that the β or γ relaxation of PPO be predominated by the local cooperative motions of several monomer units or the rotational motion of the methyl group in PPO. © 1998 John Wiley & Sons, Inc. J Polym Sci B: Polym Phys 36: 1981–1986, 1998  相似文献   
207.
208.
On the setting of the half-spaceR n–1×R +, we investigate Gleason's problem for harmonic Bergman and Bloch functions. We prove that Gleason's problem for the harmonicL p -Bergman space is solvable if and only ifp>n. We also prove that Gleason's problem for the harmonic (little) Bloch space is solvable.  相似文献   
209.
In this paper the classical method to prove a removable singularity theorem for harmonic functions near an isolated singular point is extended to solutions to the stationary Stokes and Navier—Stokes system. Finding series expansion of solutions in terms of homogeneous harmonic polynomials, we establish some known results and new theorems concerning the behavior of solutions near an isolated singular point. In particular, we prove that if (u, p) is a solution to the Navier—Stokes system in BR \{0} B_R \setminus \{0\} , n 3 3 n \geq 3 and |u(x)| = o (|x|-(n - 1)/2) |u(x)| = o\,(|x|^{-(n - 1)/2}) as |x| ? 0 |x| \to 0 or u ? L2n/(n - 1)(BR) u \in L^{2n/(n - 1)}(B_R) , then (u, p) is a distribution solution and if in addition, u ? Lb(BR) u \in L^{\beta}(B_R) for some b > n \beta > n then ( u, p) is smooth in BR.  相似文献   
210.
Zebrafish have several advantages compared to other vertebrate models used in modeling human diseases, particularly for large-scale genetic mutant and therapeutic compound screenings, and other biomedical research applications. With the impactful developments of CRISPR and next-generation sequencing technology, disease modeling in zebrafish is accelerating the understanding of the molecular mechanisms of human genetic diseases. These efforts are fundamental for the future of precision medicine because they provide new diagnostic and therapeutic solutions. This review focuses on zebrafish disease models for biomedical research, mainly in developmental disorders, mental disorders, and metabolic diseases.Subject terms: Disease model, Zebrafish  相似文献   
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