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991.
Shu Yao Minati Malide Samuel Ngaujah Li Li Zhao Li Liping Sun Zhen Huang Lin Xie Ran Chu Chengcheng Li Beihua Kong Kun Song 《Journal of the Iranian Chemical Society》2018,15(8):1733-1739
The traditional treatment has inevitable drawbacks of nonspecific lymph targeting, poor therapeutic efficiency and residual metastatic for advanced cancer patients with lymph node metastases. To overcome these shortcomings, we prepare a nano-carrier drug delivery system. Photosensitizer hematoporphyrin monomethyl ether (HMME)-loaded poly (n-butylcyanoacrylate) nanoparticles (PBCA-NPs) was prepared successfully. The particle size was approximately 160 nm, the envelopment rate was 87.9%, and the drug loading rate was about 13.4%. The drug release study in vitro showed that the cumulative release rates of HMME-PBCA-NPs group was much less than free HMME group. The drug distribution in different tissues showed that the peak-reach time was 3 h in free HMME group and 6 h in nanoparticles group. All of these results confirmed the slow release characteristic of nanoparticles. In lymph node tissues, the HMME concentrations in HMME-PBCA-NPs group were much higher than those of the free HMME group at any time points we tested, in which the maximum difference concentration of HMME appeared at 6 h (1.2884?±?0.04695 vs. 0.0438?±?0.00558 µg/mg) after drug delivery. The mesenteric lymph nodes of rabbits were enlarged obviously in the NP group than in free HMME group at 6 h after drug delivery. All of these results confirmed the slow release characteristic and the lymphatic targeting characteristic of nanoparticles. In summary, we developed a lymphatic targeting nanoparticles drug delivery system successfully, which showed perfect lymph targeting and has the potential to be a new therapy strategy for advanced cancer patients with lymph node metastasis. 相似文献
992.
Superoxide Stabilization and a Universal KO2 Growth Mechanism in Potassium–Oxygen Batteries 下载免费PDF全文
Wanwan Wang Dr. Nien‐Chu Lai Zhuojian Liang Yu Wang Prof. Yi‐Chun Lu 《Angewandte Chemie (International ed. in English)》2018,57(18):5042-5046
Rechargeable potassium–oxygen (K‐O2) batteries promise to provide higher round‐trip efficiency and cycle life than other alkali–oxygen batteries with satisfactory gravimetric energy density (935 Wh kg?1). Exploiting a strong electron‐donating solvent, for example, dimethyl sulfoxide (DMSO) strongly stabilizes the discharge product (KO2), resulting in significant improvement in electrode kinetics and chemical/electrochemical reversibility. The first DMSO‐based K‐O2 battery demonstrates a much higher energy efficiency and stability than the glyme‐based electrolyte. A universal KO2 growth model is developed and it is demonstrated that the ideal solvent for K‐O2 batteries should strongly stabilize superoxide (strong donor ability) to obtain high electrode kinetics and reversibility while providing fast oxygen diffusion to achieve high discharge capacity. This work elucidates key electrolyte properties that control the efficiency and reversibility of K‐O2 batteries. 相似文献
993.
A new palladium-catalyzed C-H amination of aryl enamines for the synthesis of trifluoromethylated indoles is established. The attractive features of this transformation are the use of atom-economical O2 as the oxidant and easily prepared enamines as substrates. A variety of pharmaceutically important 2-trifluoromethyl indoles can be targeted in moderate to good yields with good functional compatibility. 相似文献
994.
Xinchi Yin You Jiang Shiying Chu Ge Ma Qi Yin Xiang Fang Yuanjiang Pan 《Tetrahedron》2018,74(24):2921-2924
Organocopper complexes bearing bidentate nitrogen ligands were synthesized in the gas phase by electrospray ionization mass spectrometry. Gas-phase decarboylative thiolation reaction was carried out in the ion-trap analyzer by collision-induced dissociation and ion-molecule reaction. The carboxylic acids were finally converted to thioethers as a neutral loss via collision-induced dissociation. During this process, copper acetate acted as a catalyst, and the valence state change of copper was observed. Meanwhile, the mechanism of decarboxylative thiolation was examined. This reaction was also suitable for different carboxylic acids and bidentate nitrogen ligands in the gas phase. 相似文献
995.
1,2,3-Triazolium salts draw much attentions in recent years. We developed a new synthetic method to heteroatom-functionalized triazoliums via nucleophilic substitution of 4-bromomethyltriazolium. This method afforded triazoliums with different S, N, and O heteroatom-substituents. Moreover, SN2′ reaction was observed with alcohols or hydroxides. In addition, debromination and debromomethylation reaction occurred in some cases. 相似文献
996.
Wenhao Qian Zhaolei Wang Dannong He Xiaoyu Huang Jiansheng Su 《Journal of Saudi Chemical Society》2018,22(5):581-587
Excellent antibacterial property of graphene oxide makes it an important antibacterial material. However, in some cases, a synergistic combination of materials with different antibacterial mechanisms is desired. In this work, we developed a simple two-step protocol to prepare ornidazole (ONZ), a nitroimidazole antiprotozoal drug, loaded graphene-based paper for combined antibacterial materials. Graphene oxide (GO) and reduced graphene oxide (rGO) were used as carriers in antibacterial materials. After mixed with ONZ directly in aqueous media and filtrated under vacuum, the freestanding GO/ONZ and rGO/ONZ were peeled off from the filtrate membrane. The ONZ loading contents in the paper was determined by UV/vis spectroscopy and the surface properties were investigated by measuring their contact angle, which will have an important impact on the antibacterial effects of the papers. 相似文献
997.
Yuebao Zhang Qianyou Guo Xianwei Sun Ji Lu Yanjun Cao Qiang Pu Zhiwen Chu Dr. Lu Gao Prof. Dr. Zhenlei Song 《Angewandte Chemie (International ed. in English)》2018,57(4):942-946
Convergent total synthesis of bryostatin 8 has been accomplished by an organosilane‐based strategy. The C ring is constructed stereoselectively through a geminal bis(silane)‐based [1,5]‐Brook rearrangement, and the B ring through geminal bis(silane)‐based Prins cyclization, thus efficiently joining the northern and southern parts of the molecule. 相似文献
998.
Dr. Qingqing Miao Dr. David C. Yeo Dr. Christian Wiraja Dr. Jianjian Zhang Xiaoyu Ning Prof. Chenjie Xu Prof. Kanyi Pu 《Angewandte Chemie (International ed. in English)》2018,57(5):1256-1260
Early detection of skin diseases is imperative for their effective treatment. However, fluorescence molecular probes that allow this are rare. The first activatable near‐infrared (NIR) fluorescent molecular probe is reported for sensitive imaging of keloid cells, skin cells from abnormal scar fibrous lesions. As keloid cells have high expression levels of fibroblast activation protein‐alpha (FAPα), the probe (FNP1) is designed to have a caged NIR dye and a FAPα‐cleavable peptide substrate linked by a self‐immolative segment. FNP1 can quickly and specifically turn on its fluorescence at 710 nm by 45‐fold in the presence of FAPα, allowing it to effectively recognize keloid cells from normal skin cells. Integration of FNP1 with a simple microneedle‐assisted topical application enables sensitive detection of keloid cells in metabolically‐active human skin tissue with a theoretical limit of detection down to 20 000 cells. 相似文献
999.
对不同粉末粘结剂含量非织造布的研究表明:线性和非线性的简易三元件模型均能较好地描述非织造布的拉伸性能和应力松弛性能。根据模型的拟合参数计算和讨论提出了应用力学模型可以检验非织造布加工中纤维网粘结程度优劣的可能性。 相似文献
1000.
在认知无线电网络中,频谱环境的不确定性严重影响了频谱检测的准确性和可靠性。针对上述问题,提出一种基于动态信誉模型的可靠的分布式认知无线电频谱检测策略。该策略建立认知用户的频谱检测协作组,基于主观逻辑理论设计分布式节点信誉库,通过信誉的动态更新结果作为频谱检测的信道搜索顺序的依据,提高信道搜索的准确性。该策略能够对恶意用户进行有效地隔离,以避免其对频谱检测的影响,从而提高了频谱检测的可靠性。通过仿真分析可知,与其他信道搜索算法比较,根据该策略设计的分布式频谱搜索算法不仅能够有效地提高频谱检测的效率,而且能够确保频谱的可靠性,从而提高信道的利用率。 相似文献