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131.
目的观察孕期和哺乳期适度缺铁性贫血诱导子代豚鼠耳蜗毛细胞凋亡。方法 12只受孕豚鼠随机分为两组(对照组和适度缺铁性贫血组)。子代豚鼠于出生后9 d断乳,行畸变产物耳声发射(distortion product otoacoustic emission,简称DPOAE)检测听力;分离耳蜗,行全基底膜铺片,用原位末端转移酶标记技术(terminal deoxynucleotidyl transferase-mediated dUTP-biotin nickend-labelling,简称TUNEL)染色和免疫组化检测毛细胞凋亡情况。结果孕期和哺乳期铁适度缺铁性贫血致子代豚鼠听力损伤,耳蜗毛细胞凋亡发生,caspase-3/9免疫阳性表达。结论孕期和哺乳期铁缺乏适度缺铁性贫血可诱导子代豚鼠耳蜗毛细胞凋亡发生。 相似文献
132.
Cuiling Du Dr. Jie Zhao Dr. Jinbo Fei Dr. Liang Gao Wei Cui Dr. Yang Yang Prof. Dr. Junbai Li 《化学:亚洲杂志》2013,8(4):736-742
A reactive template method was used to fabricate alginate‐based hydrogel microcapsules. The uniform and well‐dispersed hydrogel capsules have a high drug loading capacity. After they are coated by a folate‐linked lipid mixture on the surface, the capsules possess higher cell uptake efficiency by the molecule recognition between folate and the folate‐receptor overexpressed by the cancer cells. Moreover, in this bioconjugate, the lipid could remarkably reduce the release rate of hydrophilic doxorubicin from the hydrogel microcapsules and encapsulate the hydrophobic photosensitizer hypocrellin B. The biointerfaced capsules could be used as drug carriers for combined treatment against cancer cell proliferation in vitro; this was much more effective than chemotherapy or photodynamic therapy alone. 相似文献
133.
Song Yun Weizhong Qian Chaojie Cui Yuntao Yu Chao Zheng Yi Liu Qiang Zhang Fei Wei 《Journal of Energy Chemistry》2013,22(4):567-572
For the synthesis of single-walled carbon nanotubes (SWCNTs) from CH4 over a Fe/MgO catalyst, we proposed a coupled Downer-turbulent fluidized-bed (TFB) reactor to enhance the selectivity and yield (or production rate) of SWCNTs. By controlling a very short catalyst residence time (1–3 s) in the Downer, only part of Fe oxides can be reduced to form Fe nano particles (NPs) available for the growth of SWCNTs. The percentage of unreduced Fe oxides increased and the yield of SWCNTs decreased accordingly with the increase of catalyst feeding rate in Downer. SWCNTs were preferentially grown on the catalyst surface and inhibited the sintering of the Fe crystallites which would be formed thereafter in the downstream TFB, evidenced by TEM, Raman and TGA. The coupled Downer-turbulent fluidized-bed reactor technology allowed higher selectivity and higher production rate of SWCNTs as compared to TFB alone. 相似文献
134.
Ming‐Yu Huang Lin‐Jing Zhong Jie‐Ming Xie Fei Wang Yong‐Hong Zhang 《Helvetica chimica acta》2013,96(11):2040-2045
3‐Oxotaraxer‐14‐en‐30‐al ( 1 ), a new taraxastane‐type triterpene, together with 14 known compounds, taraxerone ( 2 ), 3‐epiursolic acid ( 3 ), 2α,3β‐dihydroxyurs‐12‐en‐28‐oic acid ( 4 ), lupeol ( 5 ), betulinic acid ( 6 ), casticin ( 7 ), artemetin ( 8 ), luteolin ( 9 ), 4‐hydroxybenzoic acid ( 10 ), docosanoic acid ( 11 ), tetracosanoic acid ( 12 ), cerotic acid ( 13 ), β‐sitosterol ( 14 ), and β‐daucosterol ( 15 ), was isolated from the leaves and twigs of Vitex trifolia var. simplicifolia . Compounds 2 – 6 were found for the first time in this plant. Their structures were established by spectroscopic analysis, including 2D‐NMR techniques. Cytotoxic activities of compounds 3 , and 5 – 10 were tested on the three cancer cell lines, PANC‐1, K562, and BxPC‐3. Results revealed that 7 exhibited cytotoxicity against PANC‐1, K562, and BxPC‐3, with IC50 values of 4.67, 0.72, and 4.01 μg/ml, respectively, whereas 8 was inactive against these cancer cell lines. The structure? activity relationship of compound 7 and 8 indicated that the 3′‐OH group in polymethoxyflavonoids is essential for antitumor activity. 相似文献
135.
136.
Chiral derivatives of trans-1,2-diaminocyclohexane with different N,N-dialkyl groups in well-defined orientations have been synthesized, and applied as catalysts for the asymmetric aldol reaction between a variety of aldehydes and ketones. Enantiomeric catalyst 1j catalyzed the reaction in ethanol and provided excellent diastereoselectivity and enantioselectivity. Significantly, simple replacement of organic solvents with water switched the products of the aldol reactions from anti to syn configuration. Such catalytic reactions led to the products with anti to syn diastereoselectivity up to 99:1 in ethanol, while in water gave the products with syn to anti diastereoselectivity up to 99:1. 相似文献
137.
138.
Quinoline bridged imidazolium precursors 5,8‐bis(N‐R‐imidazolylidenylmethylene)quinoline PF6– salts [H2L](PF6)2 [R = Me ( 1a ), R = naphthylmethyl ( 1b )] were prepared by quaternization of N‐methylimidazole and N‐naphthylmethylimidazole with 5,8‐bis(bromomethyl)quinoline, respectively. Reaction of the imidazolium ligands 1a and 1b with Hg(OAc)2 and Ag2O in acetonitrile gave the macrocyclic transition metal carbene complexes [Hg2L2](PF6)4 ( 2a and 2b ) and [Ag2L2](PF6)2 ( 3a and 3b ), respectively. All the N‐heterocyclic carbene complexes were characterized in detail by NMR, ESI‐MS, and elemental analysis. Structures of complexes 2a and 3a were determined by X‐ray diffraction studies. Structural studies revealed that the coordination arrangement of the central mercury atom in complex 2a displays a tricoordinate mode and the molecular conformation results in a“closed” form with the bridging quinoline functionality in the macrocycle, whereas the silver complex 3a does not show an coordiantion between the bridging quinoline and the AgI ion, which results in an “open” conformation of the macrocycle. The HgII and AgI NHC complexes showed similar UV absorption and luminescence in acetonitrile solutions. 相似文献
139.
Ge‐Fei Hao Sheng‐Gang Yang Guang‐Fu Yang Chang‐Guo Zhan 《Journal of computational chemistry》2013,34(24):2055-2064
Gibberellins (GAs) are phytohormones essential for many developmental processes in plants. In this work, fundamental mechanism of hormone perception by receptor GID1 has been studied by performing computational simulations, revealing a new GA‐binding channel of GID1 and a novel hormone perception mechanism involving only one conformational state of GID1. The novel hormone perception mechanism demonstrated here is remarkably different from the previously proposed/speculated mechanism [Murase et al., Nature 2008 , 456, 459] involving two conformational states (“OPEN” and “CLOSED”) of GID1. According to the new perception mechanism, GA acts as a “conformational stabilizer,” rather than the previously speculated “allosteric inducer,” to induce the recognition of protein DELLA by GID1. The novel mechanistic insights obtained in this study provide a new starting point for further studies on the detailed molecular mechanisms of GID1 interacting with DELLA and various hormones and for mechanism‐based rational design of novel, potent growth regulators that target crops and ornamental plants. © 2013 Wiley Periodicals, Inc. 相似文献
140.
Fei Geng Ting Lu Zhen Li Liqiang Zheng Ganzuo Li 《Journal of Dispersion Science and Technology》2013,34(9):1209-1213
The effects of Tris-HCl buffer solution on the cmc of cetyltrimethylammonium bromide (CTAB) were studied by surface tension measurement. The result shows that the effect of the buffer solution depends on the interaction between CTAB and NaCl and the structure accelerants of water, Tris. A series of parameters, including the critical micelle concentration (cmc), the surface tension at cmc (γcmc), the adsorption efficiency (pC20), and the effectiveness of surface tension reduction (∏cmc) were obtained from the surface tension measurements in the presence of glycine with different concentration in the Tris-HCl buffer solution at 27°C. In addition, maximum surface excess concentration (Γ max) and minimum surface area per molecule (Amin) at the air-water interface were estimated according to the Gibbs adsorption isotherm. The thermodynamic parameters (Δ C p,m , Δ H m,tr , Δ C p,m,tr ) of micellization for CTAB in the absence and presence of glycine at different temperature were also been obtained. 相似文献