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1.
Metabolism is one of the major determinants for age-related changes in susceptibility to chemicals. Aldehydes are highly reactive molecules present in the environment that also can be produced during biotransformation of xenobiotics and endogenous metabolism. Although the lung is a major target for aldehyde toxicity, early development of aldehyde dehydrogenases (ALDHs) in lung has been poorly studied. The expression of ALDH in liver and lung across ages (postnatal day 1, 8, 22, and 60) was investigated in Wistar-Han rats. In adult, the majority of hepatic ALDH activity was found in mitochondria, while cytosolic ALDH activity was the highest contributor in lung. Total aldehyde oxidation capability in liver increases with age, but stays constant in lung. These overall developmental profiles of ALDH expression in a tissue appear to be determined by the different composition of ALDH isoforms within the tissue and their independent temporal and tissue-specific development. ALDH2 showed the most notable tissue-specific development. Hepatic ALDH2 was increased with age, while the pulmonary form did not. ALDH1 was at its maximum value at postnatal day 1 (PND1) and decreased thereafter both in liver and lung. ALDH3 increased with age in liver and lung, although ALDH3A1 was only detectible in lung. Collectively, the present study indicates that, in the case of aldehyde exposure, the in vivo responses would be tissue and age dependent. 相似文献
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目的:探讨医院气体灭菌效果和检测方法,以保证灭菌质量。方法:对本院常用的两种低温气体灭菌剂环氧乙烷和甲醛,采用枯草杆菌黑色变种芽胞生物指示管分别选择不同时间和不同方法进行灭菌效能检测。结果:环氧乙烷全自动灭菌(全过程16h)和甲醛催化法灭菌≥2h均可达到灭菌要求,而甲醛催化法灭菌时间少于2h和甲醛自然挥发法灭菌均达不到灭菌水平。结论:环氧乙烷生物指示管可应用于甲醛气体的灭菌检测;环氧乙烷全自动灭菌和甲醛催化法灭菌可用于不耐热、不耐湿的手术器械灭菌。 相似文献
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Klinefelter综合征患者和双亲对诱变剂敏感性研究 总被引:1,自引:1,他引:1
为了解诱变剂对Klinefelter综合征发生的影响,对Klinefelter综合征患者,患者双亲及对照进行丝裂霉素C,乙醛或乙醇诱导非二倍体,染色体结构畸变及微核观察,发现丝裂霉素C诱导的患者当色体结构畸变和微核均显著多于对照和双亲,乙醛和乙醇能诱导非二倍体和微核增加,但患者和双亲增加的程度极显著高于对照,提示Klinefelter综合征患者对于丝裂霉素C,乙醛和乙醇诱导染色体畸变更敏感。双亲对 相似文献
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以无毒氧化葡萄糖醛作交联剂 ,采用溶液共混交联法制备壳聚糖改性丝素合金膜。用 FTIR、DSC表征其结构 ,测定其等电点、力学性能、不同 p H条件下的溶胀率和对模型药物 5 - Fu的渗透性。结果表明 :改性丝素合金膜中丝素和壳聚糖分子间存在着强烈的氢键相互作用及良好的相容性。改性膜的等电点对应的 p H值是 5 .35 ,而丝素膜的等电点是 4 .5。改性膜的力学性能优于单组分膜 ,当壳聚糖含量为 4 0 %~ 6 0 %时 ,具有最大的抗张强度和拉伸率 ,分别为 71.4~ 72 .7MPa和 2 .96~ 3.82 %。改性丝素合金膜对 5 - Fu的渗透量与壳聚糖的含量和时间成正相关关系 ,渗透系数随 p H值增大 (5→ 9)先逐渐减小然后略有增大 ,在 p H=7时最小。 相似文献
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目的 探讨淫羊藿Epimedium brevicornu醇提物对体外巨噬细胞极化调控机制及对M2样巨噬细胞促进4T1细胞迁移和集落形成的影响。方法 采用CCK-8法检测不同浓度淫羊藿醇提物对骨髓来源巨噬细胞(bonemarrowderived macrophages,BMDM)活力的影响,确定淫羊藿醇提物的安全作用浓度;采用Western blotting和q RT-PCR检测淫羊藿醇提物对M2样巨噬细胞标志物精氨酸酶-1(arginase-1,Arg-1)和CD163表达的影响;采用q RT-PCR检测淫羊藿醇提物对M2-肿瘤相关巨噬细胞(tumor-associated macrophages,TAMs)相关基因炎症区域1(found in inflammatory zone 1,Fizz1)、过氧化物酶体增殖物激活受体γ(peroxisome proliferator-activated receptor γ,PPARγ)、几丁质酶3样分子3(chitinase 3-like 3,Ym1)、趋化因子24(C-C motif chemokine ligand 24,CCL24)、巨... 相似文献
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HPLC测定心可宁胶囊中原儿茶醛的含量 总被引:3,自引:0,他引:3
目的 采用高效液相色谱法测定心可宁胶囊中原儿茶醛的含量。方法 InertsilC1 8柱 (5 μm ,1 5 0mm× 4 .6mm) ;流动相为甲醇 - 0 .0 5mol·L-1 磷酸二氢钾缓冲液 (磷酸调pH 3.0 ) (2 0∶80 ) ;检测波长为 2 80nm。结果 原儿茶醛进样量在 0 .0 5 5 3~2 .2 1 30 μg范围内线性关系良好 (r=0 .9999) ;平均加样回收率为 99.7% (n =9) ;方法精密度RSD =0 .5 0 % (n =6 )。 结论 本方法操作简便、准确、重复性好 ,可作为该制剂中原儿茶醛的含量测定方法 相似文献
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N B Ress J R Hailey R R Maronpot J R Bucher G S Travlos J K Haseman D P Orzech J D Johnson M R Hejtmancik 《Toxicological sciences》2003,71(2):198-206
Citral, a widely used natural ingredient, is added to foods and cosmetics as a flavoring and fragrance agent. Male and female F344/N rats and B6C3F1 mice were exposed to microencapsulated citral in the feed for 14 weeks or two years. All studies included untreated and vehicle control groups. In the 14-week studies, rats and mice were given diets containing 3,900, 7,800, 15,600, or 31,300 ppm citral. In rats, food consumption was reduced in the two highest dose groups. In mice an apparent increase in food consumption was observed, but was due to mice scattering the feed. Body weights of all treated animals were less than controls. All rats and four male mice were killed moribund in the high dose groups. In rats, forestomach and kidney lesions were observed. At the higher doses, lesions observed in the bone marrow, testes, and thymus in rats and in the ovary in mice were considered related to inanition and resultant moribundity. In the two-year studies, rats were exposed to 1,000, 2,000, or 4,000 ppm citral. Body weights were reduced in the 4,000 ppm rats. Mice were exposed to 500, 1,000, or 2,000 ppm citral. Body weights in the 1,000 and 2,000 ppm groups were reduced. No neoplasms were attributed to citral in rats or mice. Malignant lymphoma occurred with a positive trend and was significantly greater than controls in female mice in the 2,000 ppm group. However, the incidences were within the NTP historical control range and could not be clearly related to citral administration. 相似文献