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1.
A novel pyropheophorbide‐a (PPa) derivative, Ac‐sPPp, was developed in our lab for targeted photodynamic therapy (PDT) and combination therapies. Its versatile peptide moiety, high water‐solubility, amphiphilicity, and micellar aggregation allow efficient coupling to targeting moieties and convenient mixing with other therapeutics. Photosensitizer immunoconjugate (PIC) targeted PDT, using Ac‐sPPp conjugated to therapeutic anti‐epidermal growth factor receptor (EGFR) antibody cetuximab, and PDT + chemotherapy combination treatment, using Ac‐sPPp mixed with stealth liposomal doxorubicin (Doxil), were investigated as promising strategies for potentiating PDT and improving target specificity. Passively targeted PDT with Ac‐sPPp only or surfactant‐solubilized PPa was also investigated for comparison. The A‐431 human vulvar squamous cell carcinoma, xenografted in nude mice, was chosen as a tumor model because of its high EGFR expression and sensitivity to liposomal doxorubicin in vitro. Fluorescence imaging and PDT experiments showed that Ac‐sPPp formulations circulated far longer and provided superior tumor contrast and superior tumor control compared to PPa. Strong PDT vascular effects were observed by laser Doppler imaging regardless of whether Ac‐sPPp was passively or actively targeted. Passively targeted Ac‐sPPp PDT gave equivalent or better tumor control than PIC‐targeted PDT or PDT + Doxil combination therapy, and when treatments were repeated, it also yielded the highest cure rate.  相似文献   
2.
本文综合评述了近年来2-[2-(二环己膦基)苯基]-1-甲基-1H-吲哚(CM-Phos)膦配体及其衍生物在钯催化的交叉偶联反应中的应用, 主要根据不同种类的交叉偶联反应进行系统性分述, 并对该领域的发展前景进行了展望.  相似文献   
3.
The effects of sulfur dioxide (SO(2)), sodium chloride (NaCl), and peroxymonosulfate or oxone (2KHSO(5).KHSO(4).K(2)SO(4) with active ingredient, HSO(5)(-)) on the sonochemical removal of nitric oxide (NO) have been studied in a bubble column reactor. The initial concentration of NO studied ranged from about 500 to 1040 ppm. NaCl in the concentration range of 0.01-0.5 M was used as the electrolyte to study the effect of ionic strength. At the low NaCl concentration (0.01 M), the percent fractional removal of NO with initial concentration of 1040 ppm was enhanced significantly, while as the NaCl concentration increased, the positive effects were less pronounced. The presence of approximately 2520 ppm SO(2) in combination with 0.01 M NaCl further enhanced NO removal. However, with a NO initial concentration of 490 ppm, the addition of NaCl was detrimental to NO removal at all NaCl concentration levels. The combinative effect of sonication and chemical oxidation using 0.005-0.05 M oxone was also studied. While the lower concentrations of HSO(5)(-) enhanced NO removal efficiency, higher concentrations were detrimental depending on the initial concentration of NO. It was also demonstrated that in the presence of ultrasound, the smallest concentration of oxone was needed to obtain optimal fractional conversion of NO.  相似文献   
4.
 利用氧化钕和盐酸为原料制得Nd(phen)2Cl3(三氯二邻菲罗啉合钕),测得其光谱特性并以稀土氧化钕、苯甲酸和邻菲罗啉为原料制得绿色液体激光介质钕离子的配合物——NdB3phen(三苯甲酸—邻菲罗啉合钕).利用飞秒激光器,采用单光束Z-扫描法研究了NdB3phen的三阶非线性光学特性.结果表明:当入射飞秒激光脉冲波长为400 nm,峰值功率密度为2.94×1014 W/m2,脉宽为117 fs时,测得样品NdB3phen的非线性折射率为-2.84×10-18 cm2/W|NdB3phen在开孔条件下呈现反饱和吸收现象,测出双光子吸收系数的值为9.11×10-12 m/W.实验结果表明,NdB3phen的双光子吸收系数和非线性折射率随着光强的增强而增大.  相似文献   
5.
采用分子设计的思想,通过多步反应合成了一种新型的以N原子为中心的蓝光发射星型有机小分子。用1H NMR,MS和元素分析进行了表征,研究了化合物的热稳定性和真空镀膜膜层的光致发光性质,用循环伏安法测定了其电化学性能。结果表明,这种合成的有机化合物光致发光性能优良(量子效率达到87%),热稳定性好,可作为制作有机电致发光器件的候选材料。  相似文献   
6.
A series of differently substituted Chugaev‐type palladium bis(acyclic diaminocarbene) complexes was screened to identify the most active catalyst for Mizoroki–Heck coupling reactions of aryl bromides with styrene. The best catalyst, which contains three methyl groups on the bis(carbene) ligand, gives excellent coupling yields at 120 °C for both activated and deactivated aryl bromides. However, activity with aryl chlorides is limited to electron‐deficient examples. The optimized catalyst demonstrates limited air and moisture stability, giving reduced yields in couplings of activated aryl bromides in open‐flask conditions. The modular synthesis of this class of catalysts should allow further fine‐tuning of activity in Mizoroki–Heck and related coupling reactions. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   
7.
Let be a bounded Lipschitz domain and consider the energy functional
with p]1,∞[ over the space of measure preserving maps
In this paper we introduce a class of maps referred to as generalised twists and examine them in connection with the Euler–Lagrange equations associated with over . The main result is a surprising discrepancy between even and odd dimensions. Here we show that in even dimensions the latter system of equations admit infinitely many smooth solutions, modulo isometries, amongst such maps. In odd dimensions this number reduces to one. The result relies on a careful analysis of the full versus the restricted Euler–Lagrange equations where a key ingredient is a necessary and sufficient condition for an associated vector field to be a gradient.  相似文献   
8.
Silks represent some of the most precious ancient and historic textile artefacts in collections worldwide.Their optimum preservation demands an appreciation of their characteristics.One important concern,especially with regard to ancient Chinese silks,is whether the fabrics have been degummed.Silks with remnant sericin gum coating the fibroin fibres would require different conservation protocol.In previous research on aged silks,the presence of sericin has been inferred from amino acid analysis of hydrolysa...  相似文献   
9.
报道了含钒(IV)和钒(V)的钨锗混合价杂多酸盐的合成、电子吸收光谱及单电子还原态的ESR谱。α-和β-[HGeV^I^VV2^VW9O40]^7^-的溶液ESR谱是由40余条超精细线组成的, 表明在阴离子中3个VO6八面体是角顶共用, 且其中一个桥氧原子是质子化的。  相似文献   
10.
The invariants of the non-degenerate representations of the group of pseudo-orthogonal matrices SO(p, 1) are constructed.  相似文献   
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