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41.
The purpose of this study was to evaluate the safety of the cefquinome sulfate liposomes by using the acute toxicity test, local irritation test and chronic toxicity test. The results showed that the LD50 of cefquinome sulfate liposomes was 639.73 mg/kg after intramuscular injection of its suspension and 95% confidence interval was 573.06 to 714.17 mg/kg. There was no significant stimulation to muscle. Subchronic toxicity test showed that the weight, haematological indexes and biochemical criterion of rabbits in variety dose had no significant difference compared with normal group (P>0.05). There was no visible pathological changes on the liver,kidney histology. According to pathological observation, the structure of liver and kidney were clear in treated and middle dose groups,but there existed disorganized hepatic cell cord in the liver and hemorrhag between glomerulopathy,tubulointerstitial and hepatic sinusoids in high dose group. All results proved that the cefquinome sulfate liposomes was safe and reliable based on the animal experiments.  相似文献   
42.
Abstract. In a laboratory study, 15N ammonium fertilizer uptake and rice growth was determined in a non-acid sulphate marine soil (Typic Tropaquept) and an acid sulphate soil (Sulfic Tropaquept). Acid sulphate sensitive (IR 26) and acid sulphate tolerant (IR 46) rice varieties were grown in soil suspensions incubated at four Eh levels (+500, +250, +50, and -150 mV) in microcosms for three weeks. The results showed that rice grown in non-acid sulphate marine soils gave slightly better dry matter weight of 1.8g/pot, greater 15N uptake of 12.8 mg N/pot, and higher total N uptake of 38.4 mg N/pot than under acid sulphate soil conditions indicating the non-acid marine soil is more favourable to rice culture. Growth as measured by weight of dry matter was significantly reduced from 2.1g/pot under oxidized condition (+500 mV) to 0.8g/pot under highly reduced condition (-150 mV). N uptake by rice was significantly reduced from 16.9 mg/pot at + 500 mV to 4.5 mg N/pot at -150 mV Total N uptake also decreased with decreasing Eh. Growth, 15N uptake and total N uptake by acid sulphate tolerant rice, IR 46 were significantly higher than the acid sulphate sensitive rice variety, IR 26. Under highly reduced soil conditions (-150 mV), growing rice in acid sulphate soil would require additions of lime, intermittent irrigation and/or mid season drainage in order to increase soil redox potential and remove toxic substances.  相似文献   
43.
十二烷基硫酸钠对大豆基木材胶黏剂的改性作用   总被引:3,自引:0,他引:3  
采用10.0g·kg^-1的十二烷基硫酸钠(SDS)改性质量分数为250.0g·kg^-1的大豆粉浆液,制成SDS改性大豆基木材胶黏剂(SF),运用单因素和正交试验法考察了pH值、反应温度和反应时间对改性SF胶耐水胶合强度的影响。试验结果表明,SDS改性大豆基木材胶黏剂的最佳工艺:pH8,反应温度35℃,反应时间4h。改性后的SF胶Ⅱ类耐水胶合强度为0.70MPa。由红外光谱分析可知,SDS改性使大豆蛋白质分子大量的非极性基团外露,增加了蛋白质分子的疏水性,提高了改性SF胶的耐水胶合强度。图4表3参10  相似文献   
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45.
对 5头健康猪口服和静脉注射国产硫酸安普霉素 ,研究其在猪体内的药代动力学和生物利用度。用微生物法测定血清药物浓度 ,结果平均回收率为 99.0 3%,血清最低检测浓度为 0 .0 5 μg/ ml,日内日间变异系数为 2 .2 %~ 5 .0 %,且血清浓度在0 .0 5~ 3μg/ m l范围呈良好线性关系 (r=0 .996 5 )。以 2 0 mg/ kg口服和以 2 0 mg/ kg静脉注射硫酸安普霉素后 ,经 Mcpkp药代动力学计算机程序处理 ,体内药物运转分别符合开放型一室和二室模型 ,生物半衰期 t1 / 2 分别为 (7.36± 1 .5 2 ) h和 (3.1 7± 0 .75 )h;CLB分别为 4 .82 L / kg· h和 0 .1 6 L / kg· h;AUC值分别为 4 .1 4和 1 30 .6 2。口服 :Cmax为 (0 .2 4± 0 .0 3)μg/ ml;Tp为 (5 .1 2±0 .6 1 ) h;T1 / 2 K为 (7.36± 1 .5 2 ) ;生物利用度 (AUCp.0 / AUCi.v)为 (3.1 92 8± 0 .70 4 4 ) %。上述药代动力学数据为动物临床用药提供有价值的理论依据  相似文献   
46.
氧化石墨烯(Graphene Oxide,GO)拥有较大的比表面积和较高的稳定性,可用来吸附水体中的多种污染物,其潜在功能稳定性具有规模化应用前景。考虑到GO在高级氧化体系中结构和形貌会发生改变,探究了经UV/H2O2和UV/过硫酸盐(Persulfate, PS)产生强氧化性自由基的体系处理后所得GOs对亚甲基蓝(Methylene Blue, MB)的吸附性能。氧化性自由基体系光源为300 W中压汞灯,30 mL GO储备液(1 mg/mL)在2种氧化体系下反应1、2、4 h后制得GOs。实验考察了不同反应条件对GOs吸附动力学的影响,傅里叶变换红外光谱(FTIR)研究了GOs氧化前后表面官能团的变化。结果显示,经UV/H2O2, UV/PS氧化1 h后,GOs表面的含氧官能团数量开始明显减少;吸附动力学过程更符合准二级动力学模型(R2>0.999);吸附热力学过程更符合Langmuir模型,MB饱和吸附量(经UV/H2O2和UV/PS氧化1、2、4 h后分别记G1-1, G1-2, G1-3, G2-1, G2-2, G2-3)依次为580.26, 591.80, 598.63, 521.77, 554.91, 568.00 mg/g。研究表明,GO可以快速吸附较大浓度范围内的MB,且对低浓度染料表现出更好的去除效果;GO对MB的吸附量随着pH值的增加逐渐增大,且在碱性条件下的增加得更明显;经氧化处理后,GOs的吸附性能随着氧化时间的增长,性能减弱,尤其在UV/PS体系中更为显著。  相似文献   
47.
聚合硫酸铁是一种新型无机高分子混凝剂。它是以硫酸酸洗废液和废铁屑为原料,以废治废,成本低,制造和使用简单。在处理工业废水的效果上优于其它混凝剂,有广阔的应用前景.  相似文献   
48.
Benzo[a]pyrene (BP) is mutagenic but noncarcinogenic in the murine colon. Recently, we reported rapid induction of colonic tumors by treatment of CD2F1 mice with BP (125 mg/kg for 5 days) followed by a colitis inducer, dextran sulfate sodium (DSS) (4% in drinking water for 1 or 2 weeks). However, there are no reports on detailed time course and histopathological features of colonic proliferative lesions in this model. Here, we show the detailed time course of colonic dysplasia, adenoma and adenocarcinoma induced by treatment with BP, DSS, and a combination of the two (BP/DSS). In the colon of mice exposed to BP/DSS, 14.6 dysplastic foci per mouse were present one week after DSS treatment (week 4). The number of dysplastic foci decreased with time to 3.1 at week 9 and thereafter remained almost constant. At week 4, 1.5 adenocarcinomas were also observed, with a marked increase in numbers with time, reaching 29.3 at week 14. In contrast, the number of dysplastic foci induced by DSS alone showed a time course similar to that following BP/DSS treatment; however, only a few tumors appeared. Neither dysplastic foci nor neoplastic lesions were induced by BP only. In mice exposed to BP/DSS, β-catenin was demonstrated immunohistochemically in the nucleus and/or cytoplasm of the tumor cells, and this translocation from the cell membrane was evident in subsets of dysplastic foci. In dysplastic foci induced by DSS alone, β-catenin was absent in the nucleus/cytoplasm. These finding suggest that aberrant β-catenin accumulation in dysplastic foci is associated with tumor progression in this BP/DSS model.  相似文献   
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50.
Ulcerative colitis (UC) is a lifelong illness with profound emotional and social impacts, and could cause serious damage to large intestine, especially in colon. However, the pathogenesis of UC remained unclear. The present study attempts to find out the role of matrix metalloproteinases-7 (MMP-7) and lysozyme in the pathogenesis of UC through a mice model induced by dextran sulfate sodium (DSS). The UC model was evaluated both by disease activity index (DAI) and the intestinal histopathology. The results show that there is a high correlation between the DAI score and the pathological changes of colon. Interleukin-6 (IL-6) serum levels and large intestinal fluids levels in UC mice are always higher than that of the control groups, which might be associated with the degree of the inflammation damage in the colon. The change tendency of the MMP-7 mRNA and protein expressions are both up-regulated firstly and then down-regulated from 1 to 5 d in the colon, but only the MMP-7 protein is up-regulated at 7 d again. The up-regulated MMP-7 levels in the early stage of UC may play a protective role through the activated defensins, while the down-regulated levels in the mid-later stage of UC may be connected with the severe lesions in the colon. However, the up-regulated MMP-7 levels in the later stage of UC in the colon may also contribute to the tissue repair or be served as a marker to CRC (colorectal cancer). The distribution of lysozyme protein indicates that there may be Paneth-like cells in the colon. Both the changes of MMP-7 and lysozyme in the small intestine may play a protective role for the safe environment of the whole gut, especially to the colon of UC.  相似文献   
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