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81.
Lone Skov Henrik Hansen Henning C. Dittmar Jonathan N. W. N. Barker Jan C. Simon Ole Baadsgaard 《Photochemistry and photobiology》1998,67(6):714-719
Sensitization on skin exposed to acute low-dose UVB irradiation separates normal humans into two phenotypically distinct groups: One group, following sensitization on UVB-irradiated skin, develops contact sensitivity, designated UVB resistant (UVB-R) and the second group, following sensitization on UVB-irradiated skin, fails to develop contact sensitivity, designated UVB susceptible (UVB-S). To investigate whether UVB susceptibility in humans is related to antigen-presenting activity in the skin we studied the effect of UVB irradiation on the number and function of the epidermal antigen-presenting cells in volunteers identified as UVB-R and UVB-S. Single cell suspensions of epidermal cells from control skin and skin exposed to 3 minimal erythema doses (MED) of UVB 3 days previously were stained for Langerhans cells (CD1a+HLA-DR+) and epidermal macrophages (CD1a-HLA-DR+). The UVB exposure of the skin significantly decreased the percentage of Langerhans cells (UVB-R: n = 7, P < 0.02, UVB-S: n = 6, P < 0.03) and increased the percentage of epidermal macrophages (UVB-R: n = 7, P < 0.03, UVB-S: n = 6, P < 0.03) however to the same degree in both the UVBR and the UVB-S group. To study the effect on Langerhans cell alloreactivity, epidermal cells were harvested immediately after UVB irradiation. However, in both UVB-R and UVB-S subjects the Langerhans cell alloreactivity was blocked to the same degree immediately after UVB irradiation compared to nonirradiated epidermal cells. To determine the effect of UVB irradiation on epidermal macrophages, epidermal cells were harvested 3 days after UVB irradiation. Irradiated epidermal cells from both UVB-R and UVB-S subjects demonstrated a strong antigen-presenting capacity compared to epidermal cells from control skin leading to activation of T cells that mainly secrete interferon (1FN)-γ and not interleukin (IL)-4. In conclusion we found that UVB susceptibility was not correlated with the number of Langerhans cells or epidermal macrophages in the skin at the same time of sensitization. Neither was it correlated with the capacity of Langerhans cells nor UVB-induced epidermal macrophages to activate T cells in vitro. 相似文献
82.
83.
Hopf H Mlynek C McMahon RJ Menke JL Lesarri A Rosemeyer M Grabow JU 《Chemistry (Weinheim an der Bergstrasse, Germany)》2010,16(47):14115-14123
In support of a deeper understanding of the chemistry of cyanoacetylene--a known constituent of planetary atmospheres and interstellar space--theoretical and experimental studies address the chemical mechanism of dimerization and trimerization, and provide high-resolution rotational spectra of two of the trimeric products, 1,2,3- and 1,2,4-tricyanobenzene. Analysis of the rotational spectra is particularly challenging because of quadrupolar coupling from three (14)N nuclei. The laboratory rotational spectra provide the basis for future searches for these polar aromatic compounds in interstellar space by radio astronomy. 相似文献
84.
The treatment of bone and cartilage defects with bioengineered constructs of artificial scaffolds and autogenous cells became the main challenge of contemporary regenerative medicine. Early defect repair may prevent secondary injury. Recent studies could prove that bone and cartilage cells are sensitive to microscale and nanoscale patterns of surface topography and chemical structure. Nanostructured materials provide an environment for tissue regeneration mimicking the physiological range of extracellular matrix. The article reviews several studies substantiating the superiority of nanostructured materials for bone and cartilage repair along with own results on cell attachment. 相似文献
85.
86.
Dawei Jiang Simone Budow Virginie Glaon Henning Eickmeier Hans Reuter Yang He Frank Seela 《Acta Crystallographica. Section C, Structural Chemistry》2010,66(4):o194-o197
The title compound, C10H12FN5O4·H2O, shows an anti glycosyl orientation [χ = −123.1 (2)°]. The 2‐deoxy‐2‐fluoroarabinofuranosyl moiety exhibits a major C2′‐endo sugar puckering (S‐type, C2′‐endo–C1′‐exo, 2T1), with P = 156.9 (2)° and τm = 36.8 (1)°, while in solution a predominantly N conformation of the sugar moiety is observed. The conformation around the exocyclic C4′—C5′ bond is −sc (trans, gauche), with γ = −78.3 (2)°. Both nucleoside and solvent molecules participate in the formation of a three‐dimensional hydrogen‐bonding pattern via intermolecular N—H...O and O—H...O hydrogen bonds; the N atoms of the heterocyclic moiety and the F substituent do not take part in hydrogen bonding. 相似文献
87.
88.
Back Cover: Imaging Glycosylation In Vivo by Metabolic Labeling and Magnetic Resonance Imaging (Angew. Chem. Int. Ed. 4/2016) 下载免费PDF全文
Dr. André A. Neves Dr. Yéléna A. Wainman Dr. Alan Wright Dr. Mikko I. Kettunen Dr. Tiago B. Rodrigues Sarah McGuire Dr. De‐En Hu Flaviu Bulat Dr. Simonetta Geninatti Crich Dr. Henning Stöckmann Dr. Finian J. Leeper Prof. Kevin M. Brindle 《Angewandte Chemie (International ed. in English)》2016,55(4):1566-1566
89.
90.
Achraf El Kasmi Henning Vieker Ling-nan Wu André Beyer Tarik Chafik Zhen-yu Tian 《化学物理学报(中文版)》2019,32(3):365-372
Thin cuprous oxide films have been prepared by chemical vapor deposition (pulsed spray evaporation-chemical vapor deposition) method without post-treatment. The synthesis ofcuprous oxide was produced by applying a water strategy effect. Then, the effect of water on the morphology, topology, structure, optical properties and surface composition of the obtained films has been comprehensively investigated. The results reveal that a pure phase of Cu2O was obtained. The introduction of a small quantity of water in the liquid feedstock lowers the band gap energy from 2.16 eV to 2.04 eV. This finding was mainly related to the decrease of crystallite size due to the effect of water. The topology analyses, by using atomic force microscope, also revealed that surface roughness decreases with water addition, namely more uniform covered surface. Moreover, theoretical calculations based on density functional theory method were performed to understand the adsorption and reaction behaviors of water and ethanol on the Cu2O thin film surface. Formation mechanism of the Cu2O thin film was also suggested and discussed. 相似文献