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排序方式: 共有3115条查询结果,搜索用时 15 毫秒
1.
灵芝菌合剂中灵芝多糖含量的测定 总被引:4,自引:0,他引:4
目的:探讨灵芝菌合剂中灵芝多糖含量的检测方法。方法:采用分光光度法,以无水葡萄糖为对照品,检测波长为490nm。结果:此方法在0~120μg范围内线性关系良好,灵芝多糖的平均回收率为99.09%。RSB为1.14%。结论:本法简便快捷,准确度高,重现性好,可作为本制剂的质控方法。 相似文献
2.
Treatment of rat heart grafts with PUVA, the combination of the photosensitizer 8-methoxypsoralen and longwave ultraviolet light, leads to a prolonged transplant survival in allogeneic recipients. A PUVA treatment of the recipient rats, performed for 7 consecutive days after transplantation, prolonged graft survival even more effectively. This may be due to the systemic immunomodulatory effects of PUVA in the recipient. One of the mediators is urocanic acid, which is transformed by ultraviolet light in the skin from its trans- to the cis-isomer, which, in turn, acts as a mediator on the immune system. An injection of cisurocanic acid into graft recipients for 7 consecutive days after transplantation resulted in prolonged graft survival; in 40% of the rats, permanent graft acceptance was observed. The significance of these results for clinical organ transplantation is discussed. 相似文献
3.
Chikako Nishigori Miran Tanaka Shin-ichi Moriwaki Sadao Imamura Hiraku Takebe 《Cancer science》1992,83(11):1172-1178
Skin tumors were produced on the back of hairless mice, HOS (HR/De), by exposure to ultraviolet B light (UVB, 290–320 nm) with 4 different protocols. The first tumors appeared earlier (in 10 weeks in group I and 7 weeks in group III) when initial intense exposure was given, followed by repeated lower-level exposures, than when the mice were exposed to the repeated UV only (in 16 weeks both in group II and group IV). All mice developed skin tumors earlier in the groups given the repeated UV exposures three times a week than in the groups given the exposures twice a week. Most of the skin tumors produced by the UVB exposure were histologically malignant, being transplantable to nude mice, and the cultured cells grown from the tumors were capable of producing tumors when injected into nude mice. The accelerated development of skin tumors by initial intense exposure and short intervals of repeated exposure observed in this study may have implications for humans who expose themselves to intense sunbathing and UV tanning (burning) by fluorescent sun lamps. 相似文献
4.
通过正硅酸甲酯(TMOS)的水解缩合反应制备了聚甲氧基硅氧烷(PMOS),其分子式可表示为:[SiOa(OH)b(OCH3)c]n。用丙烯酸-2-羟乙酯(HEA)进行酯交换后,制的功能化产物聚丙烯酰氧基甲基硅氧:烷(PAMOS),其分子式可表示为:[SiOd(OH)c(OCH3)f(OCH2CH2OCOCH=CH2)g]k。通过二氧化硅分析、红外光谱(FTIR)、凝胶渗透色谱(GPC)等方法确定了分子式中a、b、c、n及d、e、f、g、k的值,是一种比较方便、快捷且准确的方法。 相似文献
5.
尼莫地平控释片释放度试验研究 总被引:2,自引:0,他引:2
本文研究了尼莫地平控释片的释放度试验方法——转篮法,释放介质为含有22%异丙醇的0.1mol·L-1盐酸液;磷酸盐缓冲液(pH5.8)和pH7.2的溶液。含量测定方法:紫外分光光度法,在三种介质中尼莫地平分别在1~30μg·ml-1,10~50μg·ml-1和10~50μg·ml-1的范围内,浓度与吸收度有较好的线性关系。回归方程分别为A=0.615C+0.023(r=0.9999);A=0.0614C+0.012(r=0.9995);A=0.0612C+0.0088(r=0.9999)。平均回收率分别为99.63%,99.98%及100.77%,RSD(%)分别为1.34%,1.59%及1.41%。本方法的体外释放百分率与体内吸收分数有较好的相关性(r=0.991)。 相似文献
6.
Tom Lindfors Carita Kvarnström Ari Ivaska 《Journal of electroanalytical chemistry (Lausanne, Switzerland)》2002,518(2):131-138
Electrically conducting soluble polyaniline (PANI), containing different amounts of a bulky lipophilic cationic additive, tridodecylmethylammonium chloride (TDMACl), was studied by Raman (λexc=780 nm) and UV–vis spectroscopy. PANI was made simultaneously electrically conducting and soluble with bis[4-(1,1,3,3-tetramethylbutyl)phenyl]phosphoric acid in dichloromethane. The PANI membranes were prepared by drop casting on glassy carbon or ITO substrates. Raman and UV–vis measurements were carried out in a 0.1 M CaCl2 solution at potentials between 400 and ?600 mV (vs. SCE) at pH 6, or alternatively at the open circuit potential at pH 10. The results of Raman, UV–vis and cyclic voltammetric measurements confirm that the incorporation of TDMACl into the PANI membrane facilitates the oxidation and reduction of PANI. 相似文献
7.
研究了卡尔曼滤波紫外分光光度法测定复方新诺明片和增效联磺片中各组分的实验条件,结果复方新诺明片平均回收率分别为100.4±0.2%(SMZ)和100.4±0.5%(TMP);增效联磺片平均回收率分别为99.5±0.7%(SMZ)、100.8±0.6%(SD)和99.2±0.6%(TMP)。 相似文献
8.
ATP片剂的UV—HPLC测定 总被引:2,自引:0,他引:2
采用UV-HPLC法测定ATP片剂的含量,较地方标准收载的方法方便易行,重现性好。测定的回收率为100.8±1.5%。 相似文献
9.
LAURENT MICLO EMMANUEL PERRIN ALAIN DRIOU MICHEL MELLET GUY LINDEN 《Chemical biology & drug design》1995,46(2):186-192
A method for the simultaneous determination of the ratios of the three aromatic amino-acid residues in peptides was set up in acidic conditions. Binary and ternary mixtures of these amino acids were prepared, and first- and second-derivative spectra then calculated from their 0.1 nm resolution spectra between 240 and 320 nm. Certain spectral bands were chosen to differentiate tyrosine from tryptophan on the first-derivative spectra, and phenylalanine from tyrosine and tryptophan on the second-derivative spectra. Variation of the amplitude of the chosen bands was shown to be a linear function of the ratio of the aromatic amino acids in the mixture. This technique was validated with peptides whose sequence was known. The difference between theoretical and experimentally determined ratios was lower than 10%. Since the results are obtained as ratios, neither the concentration nor the nature of the peptide has to be known. The feasibility of application using a photodiode array detector with high resolution in reversed-phase high-performance liquid chromatography is discussed. © Munksgaard 1995. 相似文献
10.