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1.
Insights into the discrepant luminescence for BaSiO3:Eu2+ phosphors prepared by solid‐state reaction and precipitation reaction methods 下载免费PDF全文
Jiao Xu Yang Zhao Jingjing Chen Zhiyong Mao Yanfang Yang Dajian Wang 《Luminescence》2017,32(6):957-963
Two synthesis routes, solid‐state reaction and precipitation reaction, were employed to prepare BaSiO3:Eu2+ phosphors in this study. Discrepancies in the luminescence green emission at 505 nm for the solid‐state reaction method sample and in the yellow emission at 570 nm for the sample prepared by the precipitation reaction method, were observed respectively. A detail investigation about the discrepant luminescence of BaSiO3:Eu2+ phosphors was performed by evaluation of X‐ray diffraction (XRD), photoluminescence (PL)/photoluminescence excitation (PLE), decay time and thermal quenching properties. The results showed that the yellow emission was generated from the BaSiO3:Eu2+ phosphor, while the green emission was ascribed to a small amount of Ba2SiO4:Eu2+ compound that was present in the solid‐state reaction sample. This work clarifies the luminescence properties of Eu2+ ions in BaSiO3 and Ba2SiO4 hosts. 相似文献
2.
Yongxuan Hu Yanqing Hu Yan Lu Shiyun Huang Kangxing Liu Xue Han Zuhao Mao Zhong Wu Xianyi Zhou 《Mycopathologia》2017,182(3-4):397-402
Candida albicans is the most common pathogen that causes balanoposthitis. It often causes recurrence of symptoms probably due to its antifungal resistance. A significant number of balanitis Candida albicans isolates are resistant to azole and terbinafine antifungal agents in vitro. However, balanoposthitis caused by fluconazole- and terbinafine-resistant Candida albicans has rarely been reported. Here, we describe a case of a recurrent penile infection caused by fluconazole- and terbinafine-resistant Candida albicans, as well as the treatments administered to this patient. The isolate from the patient was tested for drug susceptibility in vitro. It was sensitive to itraconazole, voriconazole, clotrimazole and amphotericin B, but not to terbinafine and fluconazole. Thus, oral itraconazole was administrated to this patient with resistant Candida albicans penile infection. The symptoms were improved, and mycological examination result was negative. Follow-up treatment of this patient for 3 months showed no recurrence. 相似文献
3.
Development and evaluation of Trichoderma asperellum preparation for control of sheath blight of rice (Oryza sativa L.) 总被引:1,自引:0,他引:1
Li-Hua Chen Jie Zhang Sha-Sha Wang Qi-Song Miao Xin-Yu Mao 《Biocontrol Science and Technology》2015,25(3):316-328
Sheath blight, which is caused by Rhizoctonia solani, is a disease that majorly impacts rice production. A biocontrol agent used for control rice sheath blight must be sprayed on the stem at specific times during rice growth, a process that is labour-intensive and renders the antagonist vulnerable to environmental factors. In this study, Trichoderma asperellum T12 was used to produce preparation by solid-state fermentation using a surface-response method. Rice hull was selected as a carrier based on its ability to sustain the T12 floating in the water and protect T12 from ultraviolet irradiation. The production of a T12-based preparation required 32% wheat bran, 7% inoculum, 2.3 g kg?1 (NH4)2SO4 and 65% water content, with fermentation at 27.5°C for 30 days and agitation every six days. The preparation demonstrated 90% biocontrol efficacy and significantly (P > 0.05) increased the seed-set rate and 1000-grain weight as compared with the pathogen treatment. The population of Trichoderma on the surface of rice leaf sheath in the treatment applied with T12 preparation increased from 232 cfu (colony forming units) g?1 fw (fresh weight) to 436 cfu g?1 fw during rice growth stage, which was significantly (P > 0.05) higher than pathogen treatment. The population of R. solani on the leaf sheath increased from 41 cfu g?1 fw to 271 cfu g?1 fw in the pathogen treatment, while remained stable (P > 0.05) at level of 10–23 cfu g?1 fw in T12 preparation applied treatment. Biocontrol of sheath blight by the addition of the preparation to the soil is effective and decreases the costs of agro-industrial waste disposal. 相似文献
4.
Wei-wei Mao Ting-ting Wang He-ping Zeng Zhi-yu Wang Jian-ping Chen Jian-gang Shen 《Bioorganic & medicinal chemistry letters》2009,19(16):4570-4573
A library of novel 5-hydroxycoumarin and pyranocoumarin derivatives was constructed via silica sulfuric acid-catalyzed pechmann reaction and Pd(0)-catalyzed suzuki coupling in tandem, and their antiproliferative activities against breast cancer cells MCF-7 and MDA-MB-231 were evaluated. The results showed that compounds such as 6b, 6d, 6h, and 6k possess significant antiproliferative activity against MCF-7 cell line with the IC50 values of 7.2, 5.3, 3.3, and 6.5 μM, respectively. 相似文献
5.
Man Lung Yeung Jade Lee Lee Teng Lilong Jia Chaoyu Zhang Chengxi Huang Jian-Piao Cai Runhong Zhou Kwok-Hung Chan Hanjun Zhao Lin Zhu Kam-Leung Siu Sin-Yee Fung Susan Yung Tak Mao Chan Kelvin Kai-Wang To Jasper Fuk-Woo Chan Zongwei Cai Susanna Kar Pui Lau Kwok-Yung Yuen 《Cell》2021,184(8):2212-2228.e12
6.
M W Wong C B Xia M L Chen C X Zhang P S Mao G Q Nei Y Hosaka 《Japanese journal of medical science & biology》1988,41(1):31-36
Molluscicidal activity of B-2 (sodium 2,5-dichloro-4-bromophenol; called as Phebrol and registered in WHO as OMS 3012) was evaluated in a laboratory and the field trials were performed in two different localities in Yueyang city, China, for control of Oncomelania hupensis. B-2 was effective against O. hupensis both in the laboratory and in the field. A dosage of 50 g/m2 in 10% granular form or 20 ml/m2 in 25% liquid form of B-2 would be recommendable as a standard mollusciciding dose for control of O. hupensis. 相似文献
7.
Modulation of connexin 43 (cx43) in the myometrium of timed pregnant rats was studied using enzyme-linked immunosorbent assay (ELISA), immunocytochemical localization, and immunoblot. These techniques utilized site-specific antibodies directed against a portion of the carboxyl tail of cx43. We found that cx43 is synthesized several days prior to labor but accumulates within the cytoplasm until parturition, when it is rapidly transported to the plasma membrane and assembled into gap junction plaques at the cell surface. These cx43-positive gap junctions begin to disappear from the plasma membrane within hours of delivery of the last pup and are completely absent within 24 hr following delivery. These structures are apparently internalized and degraded within the cytoplasm. ELISA documents a reduction of total cellular cx43 to baseline levels within 5 days following parturition. While the timing of synthesis, cytoplasmic storage, concentration in apparent Golgi vesicles, and transport to and assembly in the plasma membrane are accelerated in three models of preterm labor, the sequence of these events and the correlation of parturition with the formation of gap junctions are identical to those documented in normal labor. These results support the hypothesis that effective labor requires the synthesis and assembly of cx43 into functional gap junctions at the myometrial cell surface. 相似文献
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We have investigated the binding of porcine pancreatic phospholipase A2 (PA2) to n-hexadecylphosphocholine (C16PN) micelles using optical detection of triplet state magnetic resonance (ODMR) spectroscopy. The zero field splittings (zfs) of the single Trp3 residue undergo significant changes upon binding of PA2 to C16PN micelles. Zfs titrations of PA2 vs C16PN indicate that the binding stoichiometry is C16PN:PA2 approximately 25. A reduction of the (E) parameter from 1.227 to 1.135 GHz is postulated to result from Stark effects caused by the binding of a polar group (possibly phosphocholine) near Trp3 in the PA2-C16PN micelle complex. 相似文献