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排序方式: 共有4528条查询结果,搜索用时 15 毫秒
891.
Robson Araújo de Freitas Junior Paloma Kênia de Moraes Berenguel Lossavaro Cndida Aparecida Leite Kassuya Edgar Julian Paredes-Gamero Nelson Carvalho Farias Júnior Maria Inês Lenz Souza Francielli Maria de Souza Silva-Comar Roberto Kenji Nakamura Cuman Denise Brentan Silva Mnica Cristina Toffoli-Kadri Saulo Euclides Silva-Filho 《Molecules (Basel, Switzerland)》2022,27(12)
The aim of this study is to evaluate the phytochemical profile, oral acute toxicity, and the effect of ylang-ylang (Cananga odorata Hook. F. & Thomson) essential oil (YEO) on acute inflammation. YEO was analyzed by gas chromatography/mass spectrometry. For in vitro tests, YEO was assessed using cytotoxicity, neutrophil chemotaxis induced by N-formyl methionyl leucyl phenylalanine (fMLP), and phagocytic activity tests. YEO was orally administered in zymosan-induced peritonitis, carrageenan-induced leukocyte rolling, and adhesion events in the in situ microcirculation model and in carrageenan-induced paw edema models. YEO (2000 mg/kg) was also tested using an acute toxicity test in Swiss mice. YEO showed a predominance of benzyl acetate, linalool, benzyl benzoate, and methyl benzoate. YEO did not present in vitro cytotoxicity. YEO reduced the in vitro neutrophil chemotaxis induced by fMLP and reduced the phagocytic activity. The oral treatment with YEO reduced the leukocyte recruitment and nitric oxide production in the zymosan-induced peritonitis model, reduced rolling and adherent leukocyte number induced by carrageenan in the in situ microcirculation model, and reduced carrageenan-induced edema and mechanical hyperalgesia. YEO did not present signs of toxicity in the acute toxicity test. In conclusion, YEO affected the leukocyte activation, and presented antiedematogenic, anti-hyperalgesic, and anti-inflammatory properties. 相似文献
892.
Kana Kobayashi-Taguchi Takashi Saitou Yoshiaki Kamei Akari Murakami Kanako Nishiyama Reina Aoki Erina Kusakabe Haruna Noda Michiko Yamashita Riko Kitazawa Takeshi Imamura Yasutsugu Takada 《Molecules (Basel, Switzerland)》2022,27(10)
Fibroadenomas (FAs) and phyllodes tumors (PTs) are major benign breast tumors, pathologically classified as fibroepithelial tumors. Although the clinical management of PTs differs from FAs, distinction by core needle biopsy diagnoses is still challenging. Here, a combined technique of label-free imaging with multi-photon microscopy and artificial intelligence was applied to detect quantitative signatures that differentiate fibroepithelial lesions. Multi-photon excited autofluorescence and second harmonic generation (SHG) signals were detected in tissue sections. A pixel-wise semantic segmentation method using a deep learning framework was used to separate epithelial and stromal regions automatically. The epithelial to stromal area ratio and the collagen SHG signal strength were investigated for their ability to distinguish fibroepithelial lesions. An image segmentation analysis with a pixel-wise semantic segmentation framework using a deep convolutional neural network showed the accurate separation of epithelial and stromal regions. A further investigation, to determine if scoring the epithelial to stromal area ratio and the SHG signal strength within the stromal area could be a marker for differentiating fibroepithelial tumors, showed accurate classification. Therefore, molecular and morphological changes, detected through the assistance of computational and label-free multi-photon imaging techniques, enable us to propose quantitative signatures for epithelial and stromal alterations in breast tissues. 相似文献
893.
Noriaki Nagai Mayu Kawaguchi Misa Minami Kana Matsumoto Tatsuji Sasabe Kenji Nobuhara Akira Matsubara 《Molecules (Basel, Switzerland)》2022,27(10)
N,N-diethyl-3-toluamide (DEET) is one of the most widely used insect repellents in the world. It was reported that a solution containing 6–30% cyclodextrin (CD) as a solvent instead of ethanol (EtOH) provided an enhancement of the repellent action time duration of the DEET formulation, although the high-dose CD caused stickiness. In order to overcome this shortcoming, we attempted to prepare a 10% DEET formulation using EtOH containing low-dose CDs (β-CD, 2-hydroxypropyl-β-CD (HPβCD), methyl-β-CD, and sulfobutylether-β-CD) as solvents (DEET/EtOH/CD formulations). We determined the CD concentration to be 0.1% in the DEET/EtOH/CD formulations, since the stickiness of 0.1% CDs was not felt (approximately 8 × 10−3 N). The DEET residue on the skin superficial layers was prolonged, and the drug penetration into the skin tissue was decreased by the addition of 0.1% CD. In particular, the retention time and attenuated penetration of DEET on the rat skin treated with the DEET/EtOH/HPβCD formulation was significantly higher in comparison with that of the DEET/EtOH formulation without CD. Moreover, the repellent effect of DEET was more sustained by the addition of 0.1% HPβCD in the study using Aedes albopictus. In conclusion, we found that the DEET/EtOH/HPβCD formulations reduced the skin penetration of DEET and prolonged the repellent action without stickiness. 相似文献
894.
Kojima Chie Watanabe Kenji Murata Hidenobu Nishio Yuki Makiura Rie Matsunaga Katsuyuki Nakahira Atsushi 《Research on Chemical Intermediates》2019,45(1):23-32
Research on Chemical Intermediates - Hydroxyapatite (HA) is a biocompatible and porous material that is useful for gene delivery. In this study, various Zn- and Mg-doped HA samples were produced by... 相似文献
895.
Dr. Shohei Yamashita Tatsuya Sudo Prof. Dr. Hidehiro Kamiya Prof. Dr. Yohei Okada 《Chemistry (Weinheim an der Bergstrasse, Germany)》2022,28(50):e202201560
Surface ligands are essential tools for the stabilization of colloidal nanoparticles (NPs) in solvents. However, knowledge regarding the effects of the ligand shell, especially the ligand length, is insufficient and controversial. Here we demonstrate solution-based experiments on n-alkylphosphonate-capped TiO2 NPs to investigate the effects of ligand length and solution temperature on colloidal stability. A robust ligand-exchange process is achieved that draws free ligands and impurities away from the colloidal solution. In the case of 8 nm anatase NPs in toluene, the dodecylphosphonate ligand provided better colloidal stability than all the other n-alkylphosphonate ligands. In addition, relaxation studies suggested there is kinetic hysteresis in the dispersion/agglomeration transition. The proposed method is applicable to a wide range of surface ligands designed to maximize the colloidal stability of NPs. 相似文献
896.
Takuma Tahara Dr. Shuichi Suzuki Prof. Dr. Masatoshi Kozaki Prof. Dr. Daisuke Shiomi Dr. Kenji Sugisaki Prof. Dr. Kazunobu Sato Prof. Dr. Takeji Takui Yota Miyake Prof. Dr. Yuko Hosokoshi Prof. Dr. Hiroyuki Nojiri Prof. Dr. Keiji Okada 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(29):7201-7209
The spin–spin and magnetic properties of two (nitronyl nitroxide)-(di-p-anisylamine-phenothiazine) diradical cation salts, ( DAA-PTZ ) + -NN⋅ MBr4− (M=Ga, Fe), have been investigated. These diradical-cation species were prepared by the cross-coupling of iodophenothiazine DAA-PTZ-I with NN-AuPPh3 followed by oxidation with the thianthrenium radical cation ( TA+⋅ MBr4−). These salts were found to be highly stable under aerobic conditions. For the GaBr4 salt, large ferromagnetic intramolecular and small antiferromagnetic intermolecular interactions (J1/kB=+320 K and J2/kB=−2 K, respectively) were observed. The magnetic property of the Fe3+ salt was analyzed by using a six-spin model assuming identical intramolecular exchange interaction (J3/kB=+320 K) and the other exchange interactions (J4/kB=−7 K and J5/kB=−4 K). A significant color change was observed in the UV/Vis/NIR absorption spectra upon electrochemical oxidation of the doublet DAA-PTZ-NN to the triplet ( DAA-PTZ ) + -NN . 相似文献
897.
898.
899.
Guan-Yeow Yeap Tiang-Chuan Hng Wan Ahmad Kamil Mahmood Masato M. Ito Yamashita Youhei Yoichi Takanishi Hideo Takezoe 《Liquid crystals》2006,33(9):979-986
A series of eight liquid crystalline compounds, N,N'-bis[(2-hydroxy-4-alkoxyphenyl)methylene]benzene-1,4-diamines, has been synthesized and characterized. These homologous compounds differ in the length of terminal alkyl group C n H2n+1 wherein n is an even number ranging from 4 to 18. The spectroscopic techniques, FTIR, 1H NMR and 13C NMR, were employed to characterize the molecular structure. The transition temperatures of all the title compounds and their mesophases were studied by differential scanning calorimetry and polarizing microscopy. All the compounds were smectogenic, exhibiting both tilted and non-tilted molecular orientation in their smectic phases. Further investigation to ascertain the anisotropic nature of subphases within the smectogenic region was carried out using X-ray diffraction. 相似文献
900.
Tanaka M. Takeiri Y. Asano E. Kaneko O. Kuroda T. Kawakami H. Yamashita Y. Uede T. 《IEEE transactions on plasma science. IEEE Nuclear and Plasma Sciences Society》1997,25(6):1412-1418
A negative-ion-based neutral beam injection (NBI) system is planned for plasma heating of the Large Helical Device (LHD). We have developed a negative ion source, which is 1/3 the scale of the source for the NBI. A magnetic filter held was generated by external permanent magnets to lower the electron temperature in a large-area bucket plasma source (35 cm×62 cm) for efficient H- production. We investigated the magnetic field configuration and found a low electron temperature high density plasma (<1 eV, 1012/cm3) could be achieved with an optimized configuration, The filter strength (Bmax=70 G, line-integral flux=780 G cm at the center axis of the source) was proved to be enough to lower the electron temperature below 1 eV at high arc discharge power (100 kW) and low pressure (0.4 Pa). We injected cesium vapor into the plasma source to enhance H- production efficiency and obtained a 16.2-A H- beam current (31 mA/cm2, 47 kV) using a large-area, four-grid electrostatic extraction system (25 cm×50 cm). This satisfied the development target (>15 A: 1/3 current of LHD ion source). Based on the results, we are designing a negative ion source for the LHD 相似文献