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1.
HAN-QI YANG HONG WANG DE-ZHU LI 《Botanical journal of the Linnean Society. Linnean Society of London》2008,156(3):411-423
The foliage leaf epidermis of 35 species representing 12 key genera of woody bamboos of the Asian tropics was investigated using light and scanning electron microscopy. The results indicated that papillae forms and distributional patterns around the stomatal apparatus of the abaxial foliage leaf epidermis were usually constant and were of great taxonomic significance at the specific and generic levels. However, papillae characters were not suitable for dividing subtribes within woody bamboos of the Asian tropics. On the basis of papillae characters, Schizostachyum s.s. and Cephalostachyum were confirmed, but their delimitations should be modified. The transfer of Leptocanna chinensis and Schizostachyum sanguineum into Cephalostachyum was supported, and Cephalostachyum virgatum and C . pergracile were confirmed to be members of Schizostachyum s.s. The subtribe Racemobambosinae did not obtain support and Racemobambos appeared to be better placed in subtribe Bambusinae. Neomicrocalamus was supported as a close relative and better treated as a synonym of Racemobambos . Gigantochloa was closely related to Dendrocalamus . © 2008 The Linnean Society of London, Botanical Journal of the Linnean Society , 2008, 156 , 411–423. 相似文献
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Jianhua Zhang Mei Liu Hongjian Jin Liandong Deng Jinfeng Xing Anjie Dong 《AAPS PharmSciTech》2010,11(2):894-903
Lactate esters are widely used as food additives, perfume materials, medicine additives, and personal care products. The objective
of this work was to investigate the effect of a series of lactate esters as penetration enhancers on the in vitro skin permeation of four drugs with different physicochemical properties, including ibuprofen, salicylic acid, dexamethasone
and 5-fluorouracil. The saturated donor solutions of the evaluated drugs in propylene glycol were used in order to keep a
constant driving force with maximum thermodynamic activity. The permeability coefficient (K
p), skin concentration of drugs (SC), and lag time (T), as well as the enhancement ratios for K
p and SC were recorded. All results indicated that lactate esters can exert a significant influence on the transdermal delivery
of the model drugs and there is a structure-activity relationship between the tested lactate esters and their enhancement
effects. The results also suggested that the lactate esters with the chain length of fatty alcohol moieties of 10–12 are more
effective enhancers. Furthermore, the enhancement effect of lactate esters increases with a decrease of the drug lipophilicity,
which suggests that they may be more efficient at enhancing the penetration of hydrophilic drugs than lipophilic drugs. The
influence of the concentration of lactate esters was evaluated and the optimal concentration is in the range of 5∼10 wt.%.
In sum, lactate esters as a penetration enhancer for some drugs are of interest for transdermal administration when the safety
of penetration enhancers is a prime consideration. 相似文献
4.
Xiao LiWei Xing Shuping Zhuo Jin ZhouFeng Li Shi-Zhang QiaoGao-Qing Lu 《Bioresource technology》2011,102(2):1118-1123
Series of nanoporous carbons are prepared from sunflower seed shell (SSS) by two different strategies and used as electrode material for electrochemical double-layer capacitor (EDLC). The surface area and pore-structure of the nanoporous carbons are characterized intensively using N2 adsorption technique. The results show that the pore-structure of the carbons is closely related to activation temperature and dosage of KOH. Electrochemical measurements show that the carbons made by impregnation-activation process have better capacitive behavior and higher capacitance retention ratio at high drain current than the carbons made by carbonization-activation process, which is due to that there are abundant macroscopic pores and less interior micropore surface in the texture of the former. More importantly, the capacitive performances of these carbons are much better than ordered mesoporous carbons and commercial wood-based active carbon, thus highlighting the success of preparing high performance electrode material for EDLC from SSS. 相似文献
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多种天敌控制多种害虫的模糊数学模型 总被引:2,自引:0,他引:2
从生态经济学的原理出发,利用模糊集理论,探讨如何评价天敌控制多种害虫的为害作用,提出了多种天敌控制多种害虫的模糊数学模型。同时又得到了天敌对害虫的控制能力C,影响率G,影响强度H,及权数ω(x)的计算公式,以及在天敌作用下安全度的讨论与分析。 相似文献
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In searching for differentially expressed genes in human uterine leiomyomas (ULs), suppression sub-tractive hybridization was used to construct an UL up-regulated library, which turned out to represent 88genes. After two rounds of screening by reverse Northern analysis, twenty genes were proved to be up-regulated, including seventeen known genes and three genes with unknown function. All these genes werefirstly associated with UL. Three genes with notable difference were selected for Northern confirmationOur results proved the authenticity of the twenty genes. One gene named Phospholipase A2 (PLA2) showedup-regulation in 4/6 of the patients and investigation of tissue distribution indicated that it had obviousexpression in prostate, testis, liver, heart and skeletal muscle. 相似文献
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Shaohui Ji Lifang Jin Xiangyu Guo Weizhi Ji 《In vitro cellular & developmental biology. Animal》2010,46(8):693-701
Studies with hepatic progenitor cells from non-human primates would allow better understanding of their human counterparts. In this study, rhesus monkey liver epithelial progenitor cells (mLEPCs) were derived from a small piece of newborn livers in chemical defined serum-free medium. Digested hepatic cells were treated in Ca2+-containing medium to form cell aggregates. Two types of cell aggregates were generated: elongated spindle cells and polygonal epithelial cells. Elongated spindle cells were expressed as vimentin and brachyury, and they were disappeared within 5 d in our cultures. The remaining type consisted of small polygonal epithelial cells that expressed cytokeratin 7 (CK7), CK8, CK18, nestin, CD49f, and E-cad, the markers of hepatic stem cells, but were negative for α-fetoprotein, albumin, and CK19. They can proliferate and be passaged, if on laminin or rat tail collagen gel, to initiate colonies. When cultured with dexamethasone and oncostatin M, the expression of mature hepatocyte markers, such as α-1-antitrypsin, intracytoplasmic glycogen storage, indocyanine green uptake, and lipid droplet generation, were induced in differentiated cells. If transferred onto mouse embryonic fibroblasts feeders, they gave rise to CK19-positive cholangiocytes with formation of doughnut-like structure. Thus, mLEPCs with bipotency were derived from newborn monkey liver and may serve as a preclinical model for assessment of cell therapy in humans. 相似文献
10.
Hailong Jin Congran Li Ding Li Ming Cai Zhouli Li Shuang Wang Xin Hong Bingyi Shi 《Cell biochemistry and biophysics》2013,67(3):1067-1074
Immunotoxins with selective cytotoxicity are frequently used as therapeutic immunosuppressive agents in solid-organ transplantation because of their efficiency and high specificity. In this study, we present a new recombinant immunotoxin termed anti-CTLA-4-scFv–melittin prepared from Escherichia coli aimed at clearing activated T cells at the same time avoiding all-round decline in systematic immunity. This fusion protein is composed of anti-CTLA-4-scFv unit and melittin analog unit with properties of low immunogenicity and selective cytotoxicity to CTLA-4-positive T cells. In preliminary biological activity assays, our results confirmed the feasibility of activated T cell clearance strategy and there were significant differences in cell survival rates between CTLA-4-positive group and control group at all experimental concentrations of the immunotoxin. The selective cytotoxicity, low immunogenicity, and low production cost make it an attractive alternate to traditional immunosuppressants. 相似文献