双酚A对豚鼠的免疫毒性

为了研究BPA(bisphenol A,双酚A)对豚鼠的免疫毒性,经口灌服,以不同剂量(500、1 000 mg/kg)染毒14 d后接种O型口蹄疫疫苗,通过分析脏器系数、淋巴细胞增殖能力、NK细胞(natural killer cell,自然杀伤细胞)活性、特异性抗体水平以及细胞免疫水平,评价BPA染毒剂量对豚鼠体液免疫和细胞免疫的影响.结果表明:与阴性对照组相比,BPA染毒后豚鼠体质量增加,心脏、肝脏、肾脏、脑、脾脏和卵巢体质量也增加,相应脏器系数升高；而胸腺、睾丸和附睾萎缩,相应脏器系数降低.NK细胞数量虽有增加,但变化不显著；BPA染毒引起NK细胞对靶细胞的杀伤能力显著下降,并且随着BPA染毒剂量的增加,其对靶细胞的杀伤能力显著下降；淋巴细胞刺激指数显著升高,并与染毒剂量呈正相关.BPA对豚鼠的特异性抗体水平有一定抑制作用,并且随着染毒剂量的增加该抑制作用愈发显著.IL-2(白介素2,interleukin-2)和IFN-γ(干扰素-γ,interferon)水平低于阴性对照组,而IL-4(白介素4,interleukin-4)水平高于阴性对照组；随着染毒剂量的增加,淋巴细胞增殖能力、IL-2和IFN-γ水平显著降低,而IL-4水平显著升高.研究显示,BPA会损伤豚鼠的免疫器官,抑制机体产生体液免疫和细胞免疫,导致免疫功能紊乱.      

Ralstonia sp.strain U2菌株对萘的趋化作用

一株降解萘的细菌Ralstonia sp. strain U2对萘具有趋化现象,萘、水杨酸都可以作为其对萘产生趋化现象的诱导物.U2菌对水杨酸、龙胆酸同样都具有趋化性,但这种趋化性是组成型的,不需要诱导.图3参22     

白眉蝮蛇毒精氨酸酯酶对CHL细胞增殖抑制和染色体畸变的影响

研究了蝮蛇清栓酶的有效成分精氨酸酯酶体外对中国仓鼠肺成纤维细胞 (CHL)增殖和染色体畸变的影响 .精氨酸酯酶的浓度以酶活单位U表示 .细胞增殖抑制试验和染色体畸变试验都用两种方法 :直接法和代谢活性法 .精氨酸酯酶设 3个浓度 :1.0× 10 -3 U /mL ,0 .5× 10 -3 U /mL和 0 .2 5× 10 -3U/mL .其中最高浓度比临床治疗浓度高约10 0倍 .细胞增殖抑制试验采用细胞贴壁培养 ,乙醇固定 ,结晶紫染色 ,单层细胞密度计测定细胞密度 .染色体畸变试验采用给药后 2 4h和 48h收集中期分裂细胞 ,低渗固定 ,制片 ,Giemsa染色 ,观察 10 0个中期分裂细胞的染色体结构异常及多倍体的出现率 .试验结果表明 ,精氨酸酯酶在上述浓度对CHL细胞的增殖没有抑制作用 ,对CHL细胞的染色体结构也没有影响 .表 2参 10     

Metabolism-independent chemotaxis of Pseudomonas sp. strain WBC-3 toward aromatic compounds

Pseudomonas sp. strain WBC-3 utilized methyl parathion or para-nitrophenol (PNP) as the sole source of carbon, nitrogen, and energy, and methyl parathion hydrolase had been previously characterized. Its chemotactic behaviors to aromatics were investigated. The results indicated that strain WBC-3 was attracted to multiple aromatic compounds, including metabolizable or transformable substrates PNP, 4-nitrocatechol, and hydroquinone. Disruption of PNP catabolic genes had no e?ect on its chemotactic behaviors w...     

论佛教折射的环保理念与环保实践

综观人类历史，宗教与现实生活联系紧密，在各类社会问题的解释与解决中一直发挥着不可小觑的作用。随着全球环境问题的日益突出，佛教中所体现的环保理念日益引起人们的重视。本文试从佛教环保理念的思想渊源入手，围绕自然观、生命观和理想观等内容来探讨佛教与其环保实践问题。     

Augmentation of tribenuron methyl removal from polluted soil with Bacillus sp. strain BS2 and indigenous earthworms

Tribenuron methyl (TBM) is a member of the sulfonylurea herbicide family and is widely used worldwide. In this study, TBM-degrading bacteria were enriched with TBM as potential carbon, nitrogen or sulfur source, and 44 bacterial isolates were obtained. These isolates were phylogenetically diverse, and were grouped into 25 operational taxonomic units and 14 currently known genera. Three representatives, Bacillus sp. strain BS2, Microbacterium sp. strain BS3, and Cellulosimicrobium sp. strain BS11, were selected, and their growth and TBM removal from culture broth were investigated. In addition, indigenous earthworms were collected and applied to augment TBM degradation in lab-scale soil column experiments. Results demonstrated that Bacillus sp. strain BS2 and earthworms significantly increased TBM removal during soil column experiments.     

Analysis of degradation and pathways of three common antihistamine drugs by NaClO,UV, and UV-NaClO methods

Environmental Science and Pollution Research - Antihistamines (ANTs) are medicines to treat allergic diseases. They have been frequently detected in the natural water environment, posing potential...