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流域场镇式发展是三峡地区城乡统筹发展的重要模式，通常形成河流两岸串珠状的场镇分布格局，这种人类活动的点状聚集特征对入库河流水环境的综合影响并不清楚.选择三峡库区流域场镇发展特征明显的黑水滩河及主要支流为研究对象，于2014年9月至2015年6月期间对流域内分布的主要场镇前后的水体进行碳、氮、磷浓度的监测分析，探讨场镇分布对流域水体生源要素时空格局的影响.研究结果表明，黑水滩河干、支流水体总有机碳（TOC）和溶解性有机碳浓度为4.5~39.2和3.2~31.4 mg/L，总氮（TN）、铵态氮和硝态氮浓度范围为1.12~6.96、0.87~5.00和0.073~0.881 mg/L，总磷（TP）、溶解性总磷和正磷酸盐浓度范围为0.078~0.454、0.049~0.310和0.025~0.222 mg/L，不同形态的碳、氮、磷含量变化幅度较大；黑水滩河干、支流流经不同场镇区前后，水体各形态碳、氮、磷浓度均不同程度增加（其中TOC、TN和TP的增幅范围分别为4.7%~61.3%、26.7%~144.7%和12.8%~50.7%），而在无场镇分布的干流河段，水体碳浓度变化不大，氮、磷浓度明显降低，表明水体生源要素的空间变异特征受到流域场镇分布格局与河流自净能力的双重影响，导致黑水滩河干流自上游向下游碳浓度呈“阶梯式”增长，氮、磷浓度呈“波动式”增长；相关分析显示，流域水体碳、氮、磷浓度均呈极显著的正相关关系，即场镇发展模式下河流水体污染物呈同步变化的趋势，表明山地河流流域内串珠状场镇发展模式导致从上游向下游水体污染物呈明显的累积效应，并进一步超出水体自净能力，造成下游水体恶化.河流碳、氮、磷浓度的季节变化主要受径流稀释作用影响，表现为夏秋季低、春季高的模式；富营养化综合指数表明，黑水滩河各监测断面全年属于富营养状态以上，表层水体氮污染严重，磷污染较轻；初步估算黑水滩河每年向三峡水库输入TOC、TN、TP通量达4057、1001和47 t，对三峡水库水环境安全具有严重威胁.三峡库区沿河串珠状场镇式发展形成了一种“点-面”双重特征的污染模式，未来河流水环境污染防控中应予以关注.

Exclusive enteral nutrition (EEN) has been proven to be effective and safe in treating pediatric Crohn’s disease (CD). EEN induces pediatric CD remission possibly through three pathways: (1) direct anti-inflammatory effects, (2) improved epithelial barrier function, and (3) modulation of the gut microbiota. Recent studies have demonstrated that modulation of the gut microbiota plays a major role in EEN-induced remission. Variations of microbial components, which directly influence the diversity and metabolic functions of the gut microbiota, are closely associated with the immunological conditions of the gut and the susceptibility to diseases. The reduction of proinflammatory microbial components and harmful microbial metabolites after EEN treatment greatly decreases the inflammatory injuries of the gut.

A considerable number of studies have been conducted to study the microbial profiles in inflammatory conditions. A common phenomenon in inflammatory bowel disease (IBD) is the reduction of the diversity of microbiota, which demonstrates that microbial diversity negatively correlates with disease severity in IBD. Increased microbial diversity is known to occur in disease remission. Species diversity plays an important role in maintaining the stability of the intestinal ecosystem as well as normal ecological function. A reduction in microbial diversity corresponds to a decrease in the stability of the ecosystem and can impair ecological function. Fecal microbiota transplantation (FMT), probiotics, and prebiotics, which aim to modulate the microbiota and restore its normal diversity, have been shown to be clinically efficacious. In this study, we hypothesized that a reduction in microbial diversity could play a role in the development of IBD.

A novel glassy carbon electrode (GCE) modified with bromothymol blue (BTB) and multi-walled carbon nanotubes (MWNTs) is described, and the electrochemical behavior of 5-fluorouracil (5-Fu) on the modified electrode was investigated by cyclic voltammetry. Various kinetic parameters such as transfer electron number and diffusion coefficient were calculated. A good linear relationship between the oxidation peak current and logarithmic concentration of 5-Fu in range of 8 × 10−7 to 5 × 10−3 M (R2 = 0.9981) was obtained in phosphate buffer solution (pH 6.8); the detection limit was 2.67 × 10−7 M (S/N = 3) by use of MWNTs/BTB/GCE. It was successfully applied to the 5-Fu determination in injections.