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31.
采用盐酸萘乙二胺分光光度法对焯水椿芽、新鲜椿芽用食盐水腌渍一段时间后,测定其亚硝酸盐的含量,为人们的日常饮食、蔬菜加工提供科学依据[1]。结果表明:香椿芽用开水焯过后其亚硝酸盐的含量有大幅度降低,且腌渍8天后,亚硝酸盐含量逐渐降低并趋于平稳,低温储存有利于亚硝酸盐含量的降低。  相似文献   
32.
The study was aimed to extract stachydrine hydrochloride in leonurus by HPLC-ELSD,and establish hydrochloride stachydrine determination methods for providing theoretical basis of leonurus extraction process optimization.The chromatographic conditions:venusil HILIC hydrophilic column;Mobile phase was acetonitrile -0.2% acetic acid solution (volume ratio 80:20);The flow rate was 1.0 mL/min;And the column temperature was 30 ℃;The detector was ELSD and drift tube temperature was 80 ℃ with the atomization chamber temperature 50 ℃ and carrier gas volume flow 1.0000 mL/min.The results showed that there was a good linear relationship when the stachydrine hydrochloride content was 0.49 to 4.91 μg (R2=0.9993);There was the highest rate of active ingredients extraction of when the extraction time was 1 h,material to water ratio was 20:1 and extracted for 2 times.Combined with production practice,the final optimization scheme was that the extraction time was 1.5 h,material to water ratio was 20:1 and extracted for 2 times.In summary,the determination of stachydrine hydrochloride in leonurus should use HPLC-ELSD method which had high specificity,good stability,response and reproducibility and easy to handle.This method could provide the theoretical basis for optimizing the leonurus extraction process.  相似文献   
33.
研究临床使用常规剂量及养殖环节加大盐酸土霉素可溶性粉剂量后其在鸡蛋中的残留消除规律。对产蛋期蛋鸡分别给予500 mg/L和667 mg/L 50%盐酸土霉素可溶性粉,集中饮水给药,每日1次,连续5 d。分别采集停药后1~12 d的鸡蛋样品,采用UPLC-MS/MS测定鸡蛋中土霉素的残留量。按上述方法给药后,低、高剂量组分别在停药第1天和停药第2天达到土霉素残留量最高。低、高剂量组的最高残留量分别为142. 72、82. 84μg/kg,均低于国家规定的最高残留限量(200μg/kg),不会造成土霉素残留超标。本试验通过研究土霉素可溶性粉在鸡蛋中的残留情况,确定弃蛋期前后土霉素残留量,以期为蛋鸡产蛋期安全用药,保障食品安全提供科学依据。  相似文献   
34.
研制加味当归四逆壳聚糖喷膜剂,并且制定生产工艺和质量标准。试验采用水煎法提取处方药材;通过正交试验确定壳聚糖盐酸盐、PVPK-30以及乙醇成膜材料的最佳配比;按照药典相关规定,采用紫外分光光度法测定每瓶总黄酮的含量。成膜材料的最佳配比为壳聚糖盐酸盐1%,3%PVPK-30和40%乙醇。通过TLC鉴定样品含有阿魏酸和芍药苷成分。质量标准中性状为澄清有清凉气味的红棕色液体,总黄酮的含量1.83 mg/mL。以处方为219 mg/mL中药复方,1%的壳聚糖盐酸盐,3%的PVPK-30以及40%的乙醇制备出加味当归四逆壳聚糖喷膜剂,且制定质量标准中样品含有阿魏酸和芍药苷并且每瓶总黄酮含量满足1.83 mg/mL。  相似文献   
35.
试验旨在探讨碘量法测定日粮、食糜及排泄物中半胱胺盐酸盐(cysteamine hydrochloride,CSH)含量的改进方法,为评估包膜CSH在动物胃肠道内释放过程中CSH的定量提供参考。试验分3部分:试验一:检验包膜CSH的上样量对碘标准液消耗量的线性关系,以确定碘量法检验包膜产品的准确度,采用单因素完全随机设计,CSH的上样量设6个水平,分别为28.28、113.12、226.24、339.36、452.48和565.61mg;试验二:考察H2SO4预处理对消除日粮、食糜和排泄物对碘量法测定CSH含量的影响,采用单因素完全随机设计,日粮、十二指肠食糜、空肠食糜、回肠食糜及排泄物样品中CSH(试剂级)的含量均设3个水平,即30、100和300mg/2g,形成15个含有CSH的样品,H2SO4溶液(6mol/L)设3个水平,即0.1、0.5和1mL,每个处理设3个重复;试验三:考察传统碘量法与试验二建立的改进方法在测定日粮、食糜及排泄物中包膜CSH含量的差异,采用两样本试验设计,日粮、十二指肠食糜、空肠食糜、回肠食糜及排泄物中CSH的含量均设28.73、84.84、141.47和200.56mg/2g。结果表明:①CSH的上样量对碘标准液消耗量及CSH测定值均呈显著的线性关系(P<0.01,R2=0.9999)。②在含有CSH的日粮中,H2SO4溶液处理后由碘量法测定的CSH质量对实际质量的回归均符合Y=X(P>0.05)。在含有CSH的十二指肠食糜和回肠食糜中,所有H2SO4溶液处理下CSH质量对实际质量的回归均不符合Y=X(P<0.05),但0.5和1.0mL比0.1mL H2SO4溶液处理使测定值更接近实际值。在含有CSH的空肠食糜及排泄物中,0.5和1.0mL H2SO4溶液处理使测定值对实际值的回归符合Y=X(P>0.05),而0.1mL H2SO4溶液处理下CSH测定值显著低于实际值(P<0.01)。③在含有CSH的日粮、十二指肠食糜、空肠食糜、回肠食糜及排泄物样品中,常规方法测定的CSH对实际质量均偏离Y=X(P<0.05),而1.0mL H2SO4溶液处理后的测值对实际质量均符合Y=X(P>0.05)。由此可见,采用适量H2SO4溶液进行处理后,可以排除日粮、食糜及排泄物对CSH测定的干扰。  相似文献   
36.
AIM:To investigate the effects of titanium dioxide (TiO2) nanotube arrays on the early adhesion behavior of Porphyromonas gingivalis (Pg), Tannerella forsythia (Tf) and Actinobacillus actinomycetemcomitans (Aa) before and after loaded with minocycline hydrochloride (MN). METHODS:TiO2 nanotube arrays were prepared by ano-dization and loaded with MN. Titanium slices were divided into 3 groups according to different treatment methods:pure polishing titanium (Ti) group, TiO2 nanotube titanium (TiO2) group, and MN (120 μg) TiO2 nanotube titanium (MN TiO2) group. The antibacterial properties of the titanium tablets were evaluated by the bacteriostasis test.RESULTS:The Ti had no antibacterial activity. The antibacterial activity of TiO2 to Aa, Pg and Tf was poor, with only about 20% of antibacterial rate after 4 h. After loaded with MN, its antibacterial activity was enhanced, and the antibacterial rate was up to 77% after 4 h.CONCLUSION:No antibacterial activity in the Ti group was observed. If TiO2 nanotube arrays were formed on the surface and MN was loaded, the antibacterial activity on periodontal pathogens was stronger.  相似文献   
37.
为同时检测黄连解毒散中非法添加的对乙酰氨基酚和盐酸溴己新,以十八烷基键合硅胶为填充剂,1%冰醋酸溶液(用三乙胺调剂p H值至4.0)为流动相A,甲醇为流动相B,进行梯度洗脱,流速为1.0 m L/min,波长扫描范围为210~400 nm,柱温25℃,建立了HPLC-PAD检测方法,并采用峰纯度检查和光谱相似度检查辅助对照品比对方法,对非法添加药物进行确证。结果显示,对乙酰氨基酚和盐酸溴己新的回收率分别为98.6%和99.4%,RSD分别为0.6%和0.2%;线性方程分别为y=43408x-401.96,R2=1和y=14331x-1682.4,R2=1;检测限分别为1和5 mg/g;定量限分别为2和10 mg/g。本方法简洁、灵敏、可靠,可同时对黄连解毒散中非法添加的对乙酰氨基酚和盐酸溴己新违禁药物进行定性和定量检测。  相似文献   
38.
Y. Chen    E. Kenaschuk  P. Dribnenki 《Plant Breeding》1998,117(5):463-467
The effects of induction medium compositions on flax anther culture were investigated in order to improve the efficiency of callus induction and plant regeneration. Anthers were inoculated onto the modified MS medium supplemented with five different combinations of plant growth regulators. The medium containing the combination of 2mg/l 2,4- dichlorophenoxy-acetic acid (2,4-D) and 1 mg/1 6-benzylaminopurine (BAP) produced a significantly higher number of calli forming shoots/100 responded anthers and a significant increase in overall efficiency of regeneration than the same basal medium containing 1 mg/1 a-naphthalene-acetic acid (NAA) and 2 mg/1 BAP (CK). Among the five levels of thiamin hydrochloride tested, the modified MS medium containing 10 mg/1 thiamin hydrochloride significantly increased the number of calli forming shoots/100 responded anthers and the overall efficiency of regeneration compared with the same basal medium containing 0.1 mg/1 thiamin hydrochloride. Maltose concentration had a significant effect on the percentage of anthers producing call, the number of calli forming shoots/100 responded anthers and the overall efficiency of regeneration. The medium containing 6% or 9% maltose produced the highest overall efficiency of regeneration among the five levels of maltose evaluated. Sucrose concentration significantly affected the number of calli forming shoots/100 responded anthers and the overall efficiency of regeneration, and dramatically affected the frequency of microspore-derived plants and the frequency of spontaneous chromosome doubling in microspore-derived plants. The efficiency of doubled haploid line production obtained in this study appears adequate for applied breeding programmes.  相似文献   
39.
国产盐酸沙拉沙星体外抑菌活性研究   总被引:2,自引:0,他引:2  
采用微量稀释法,测定了国产盐酸沙拉沙星对9种118株畜禽常见病原微生物的体外抑制活性。该药物对被检7株支原体的作用较差,MIC为3μg/ml,而对革兰氏阴性菌和革兰氏阳性菌的抑菌活性强,MIC小于或等于0.5μg/ml,其中:对革兰氏阴性菌作用更强,除绿脓杆菌外,MIC小于等于0.125μg/ml,盐酸沙拉沙星的MIC(最低抑菌浓度)曲线与MBC(最低杀菌浓度)曲线比较接近,表明该药物为一杀菌剂,  相似文献   
40.
环丙沙星是高效广谱抗菌新药,将其同透皮吸收促进剂(Azone)按药剂学方法制成盐酸环丙沙星搽剂,稳定性良好.将药液涂搽于仔猪体表,用以防治哺乳仔猪大肠杆菌病,获得满意效果.  相似文献   
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