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研究了孔雀石绿、高锰酸钾和甲醛对褶皱臂尾轮虫的急性毒性.结果表明:孔雀石绿、高锰酸钾和甲醛溶液对褶皱臂尾轮虫的毒性作用随浓度的增加而变大,这三种药物对褶皱臂尾轮虫的急性毒性顺序为:孔雀石绿>高锰酸钾>甲醛;孔雀石绿、高锰酸钾和甲醛对褶皱臂尾轮虫24 h的LC50分别是0.613 mg·L-1、0.873 mg·L-1和11.277 mg·L-1,其相应的安全浓度分别为6.13 μg·L-1、8.73 μg·L-1和112.77 μg·L-1. 相似文献
124.
采用密度泛函理论方法,在B3LYP/6-31G(d)理论水平下,计算了45种苯砜基羧酸酯化合物的量子化学参数.经多元线性回归分析,得到描述此类化合物对发光菌急性毒性的模型:-lgEC50=3.02 6.24EHOMO-0.091μ-0.006P 1.22q(1)-6.67q(10),其中R=0.92,r2adj=0.82,F=42.0,q2=0.79.通过对模型进行分析,得到如下结论:苯环和酯基取代基的电负性越大,分子体积越小,毒性越大.该研究为探讨此类化合物急性毒性的机理奠定了理论基础. 相似文献
125.
Yeliz Yikilmaz Ozgur Kuzukiran Ekrem Erdogan Filiz Sen Ozlem Kirmizibayrak Ayhan Filazi 《Biomedical chromatography : BMC》2020,34(10):e4926
We aimed to develop a rapid, simple and reproducible method based on LC–tandem mass spectrometry (LC–MS/MS) to analyze β-agonist residues (clenbuterol, zilpaterol, ractopamine and isoxsuprine) in bovine tissues. The method was validated in accordance with the European Council Decision 2002/657/EC. The samples were homogenized, and then 10 mL of an acetate buffer was added to a 5-g sample. The sample was then centrifuged at 12,000 rpm and filtered. Sodium hydroxide (2 m ) was added to adjust pH of the sample that was centrifuged again. The extract was filtered through a solid-phase extraction column. The residue was re-dissolved in 250 μL acetonitrile and then subjected to LC–MS/MS. The separation was done on a C18 column. The mobile phase consisted of 0.1% formic acid in deionized water and 0.1% formic acid in methanol. The mean recoveries of β-agonists were in the range of 84.3%–119.1% with relative standard deviations (%RSDs) of 0.683%–4.05%. Decision limits and detection capabilities of the analytes ranged from 0.0960 to 4.9349 μg/kg and from 0.0983 to 5.0715, respectively. This method was used to detect four β-agonists in 100 bovine muscle, 100 liver and 100 kidney tissues from a slaughterhouse. No residue was found above the maximum residue limit level. 相似文献
126.
Xueting Yao Chao Xu Yurong Cao Lin Lin Hanxu Wu Chang Wang 《Biomedical chromatography : BMC》2019,33(3)
Radiation‐induced brain injury involves acute, early delayed and late delayed damage based on the time‐course and clinical manifestations. The acute symptoms are mostly transient and reversible, whereas the late delayed radiation‐induced changes are progressive and irreversible. Therefore, evaluation of the organ‐specific early response to ionizing radiation exposure is necessary for improving treatment strategies and minimizing possible damage at an early stage after radiation exposure. In the current study, the gas chromatography–mass spectrometry technique based on metabolomics coupled with metabolic correlation network was applied to investigate the early metabolic characterization of rat brain tissues following irradiation. Our findings showed that the metabolic response to irradiation was not just limited to the variations of individual metabolite levels, but also accompanied by alterations of network correlations among various metabolites. Metabolite clustering indicated that energy metabolism disorder and inflammation response were induced following radiation exposure. The correlation networks revealed that the strong positive correlations of differential metabolites were highly reduced and significant negative linkages were highlighted in irradiated groups even without statistical changes in metabolic levels. Our findings provided new insights into our understanding of the radiation‐induced acute brain injury mechanism and clues as to the therapy target for clinical applications. 相似文献
127.
为研究重金属对海洋生物的毒性影响及敏感性, 本文以海水模式鱼—–海水青鳉(Oryzias melastigma)为对象, 分析4种代表性海水重金属污染物铜、镉、铅、汞对其胚胎发育和仔鱼生长期的24h急性毒性. 结果显示: 海水青鳉发育阶段对4种重金属离子都很敏感, 且都产生明显毒性影响. Hg2+、Cu2+、Pb2+、Cd2+对海水青鳉胚胎发育期24h LC50最低值分别为2.34μg?L-1 (I期)、0.72mg?L-1 (IV期)、22.65μg?L-1 (I期)、27.32μg?L-1 (I期), 对青鳉胚胎发育毒性大小的排序为Hg2+>Pb2+>Cd2+>Cu2+. Hg2+、Cu2+、Pb2+、Cd2+对海水青鳉仔鱼期24h LC50最低值分别为0.018 mg?L-1 (7日龄)、0.48mg?L-1 (8日龄)、1.87mg?L-1 (6日龄)、1.86mg?L-1 (5日龄), 对青鳉仔鱼毒性大小的排序为Hg2+>Cu2+>Cd2+>Pb2+. 由此得出重金属对海水模式鱼的胚胎和仔鱼发育的敏感期, 并经实验得到其最低敏感浓度, 也为进一步开展海水重金属的生物监测提供了参考依据. 相似文献
128.
《应用有机金属化学》2017,31(12)
The formation of a complex between Ga(III) and morin (3,5,7,2′,4′‐pentahydroxyflavone) was studied. UV–visible, infrared and mass spectroscopies were used to characterize the complex. The stoichiometric ratio for the reaction between metal ion and flavonoid was determined using the methods of Yoe–Jones and Job, which confirmed that a 1:1 Ga–morin complex was formed (estimated binding constant = 2.31 × 104 l mol−1). It was found that the coordination to Ga(III) occurs through the carbonyl oxygen atom and the 3‐OH group of the morin molecule. According to developed conditions, complexation reaction with 68Ga was performed and the complex was used to label kidney cancer cells (CAKI‐1, CAKI‐2, ACHN and 786‐O). The knowledge gained from this study should be useful for the development of new radiopharmaceuticals for diagnostic purposes containing 68Ga. 相似文献
129.
网球发球的背肌损伤原因及康复 总被引:1,自引:0,他引:1
运用运动解剖学的基本知识和方法,对网球发球背肌损伤的不同征象和原因作了详细的分析,并依据受伤的不同情况,给出了切合实际的治疗措施和康复训练方案。 相似文献
130.
目的 探讨脑外伤患者血浆脂联素水平的变化规律及与脑外伤严重度的相关性。方法 选取86例重型脑外伤患者
和86例健康体检者,分别于入院时、入院后第1、2、3、5、7天和体检时清晨空腹抽取静脉血,ELISA 法测定血浆脂联素水平。结果 脑外伤后血浆脂联素水平6h内升高,24h到达高峰,后逐渐下降,入院时、入院后第1、2、3、5、7天的血浆脂联素水平均明显高于健康对照组(均P<0.01);蛛网膜下腔出血、环池消失、中线移位(>5mm)和瞳孔散大患者各个时间点血浆脂联素水平显著高于其对照组(均P<0.01)。入院时格拉斯哥昏迷评分与各个时间点血浆脂联素水平均呈负相关(均P<0.01)。结论 脑外伤后血浆脂联素水平升高,与脑外伤严重度显著相关。 相似文献