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201.
Huo M  Yang JC  Guan YF 《生理科学进展》2009,40(4):337-340
碳水化合物反应元件结合蛋白(carbohydrate response element binding protein,ChREBP)是一个在糖脂代谢过程中发挥重要作用的转录因子.ChREBP的分子量约为90kD,含有四个与其活性紧密相关的磷酸化位点.葡萄糖代谢旁路产物5-磷酸木酮糖可以激活蛋白磷酸酶2A,其促使ChREBP去磷酸化,去磷酸化的ChREBP进入细胞核,并与MLX形成异源二聚体ChREBP/MLX,ChREBP/MLX结合到靶基因启动子区域的ChRE上,激活靶基因的转录.ChREBP的靶基因主要是参与糖酵解和脂质合成的一些酶类,因而ChREBP的激活可促进葡萄糖向脂质转化.敲除ChREBP的小鼠虽可正常生长发育但其体内脂肪组织明显减少,同时肝中有大量糖原堆积而导致肝肿大.敲除ChREBP的ob/ob小鼠,体重及糖脂代谢紊乱也有明显改善.总之,现有的研究揭示ChREBP有可能成为治疗代谢综合征的一个新靶点.  相似文献   
202.
大黄醇提液抗家兔实验性高脂血症及脂肪肝的实验研究   总被引:11,自引:0,他引:11  
目的:检验大黄醇提液抗家兔实验性高脂血症及脂肪肝的影响。方法:将30只雄性健康白兔随机分为5组(n=6):对照组给予基础饲料;模型组给予高脂饲料;三个大黄组给予高脂饲料同时分别灌胃不同药量的大黄醇提液。实验过程中进行一般性指标观测,检测不同阶段五组家兔血脂水平,检测脂肪肝病变程度。结果:大黄醇提液具有降低血清甘油三酯(TG)、低密度脂蛋白胆固醇(LDL-C),升高高密度脂蛋白胆固醇(HDL-C),降低肝细胞脂肪变性的作用。并且大黄醇提液的以上作用存在一定的量效关系。结论:大黄醇提液可降低动脉粥样硬化兔模型的血脂水平、降低脂肪肝的发生发展。  相似文献   
203.
204.
A new strain of Manila clam with orange shell color was produced after selection within a full-sib family for two generations. In the present study, the shell length, height, and width, and the live body weight of the orange strain were measured, and their correlation coefficients were calculated. The shell morphological traits were used as independent variables, and the live body weight was used as the dependent variable for calculating the path coefficients, correlation index, and determination coefficients. The results showed that the correlation coefficients between each shell morphological trait and the live body weight were all highly significant (P < 0.01). The correlation indices (R2) of morphological traits against the live body weight of clams were larger than 0.85, indicating that the morphology traits were the main factors affecting the body weight. Multiple regression equations were obtained to estimate shell length X1 (cm), shell height X2 (cm), and shell width X3 (cm) against live body weight Y (g): Y = ? 2.62 + 0.34 X1 + 0.145 X2, (X1 < 0.05, X2 < 0.05). The results suggest that the shell length could be used as the main trait for selective breeding and could indirectly make a large improvement in the weight trait.  相似文献   
205.
206.
The renewable pine needles was used as an adsorbent to remove phosphorus from aqueous solutions. Using batch experiments, pine needles pretreated with alkali-isopropanol (AI) failed to effectively remove phosphorus, while pine needles modified with lanthanum hydroxide (LH) showed relatively high removal efficiency. LH pine needles were effective at a wide pH ranges, with the highest removal efficiency reaching approximately 85% at a pH of 3. The removal efficiency was kept above 65% using 10 mg/L phosphorus solutions at desired pH values. There was no apparent significant competitive behavior between co-existing anions of sulfate, nitrate, and chloride (SO4 2-, NO3 - and Cl-); however, CO3 2- exhibited increased interfering behavior as concentrations increased. An intraparticle diffusion model showed that the adsorption process occurred in three phases, suggesting that a boundary layer adsorption phenomena slightly affected the adsorption process, and that intraparticle diffusion was dominant. The adsorption process was thermodynamically unfavorable and non-spontaneous; temperature increases improved phosphorus removal. Total organic carbon (TOC) assays indicated that chemical modification reduced the release of soluble organic compounds from 135.6 mg/L to 7.76 mg/L. This new information about adsorption performances provides valuable information, and can inform future technological applications designed to remove phosphorus from aqueous solutions.  相似文献   
207.
208.
In this study the length–weight relationships of 23 fish species belonging to eight families and 21 genera from the Ergis River in China were analyzed. A total of 1869 specimens were used to estimate the relationship parameters. Seven of these fish species and one maximum length are new to science against FishBase. The r2 value ranged from 0.975 to 0.999. Values of b varied from 2.630 to 3.494.  相似文献   
209.
Psoriasis is a chronic disease which carries the emotional and social burden, promotes joint disability and raises comorbidity possibility in patients. Obesity is closely correlated with the occurrence of psoriasis and adipokines produced by adipose tissues were found to be critical culprits. Chemerin is one of them and its expression was increased in patients with psoriatic arthritis. In our hypothesis, chemerin might act on keratinocytes and promote an inflammatory response, which plays an essential role in psoriatic epidermis. To validate our hypothesis, HaCaT cells and primary human keratinocytes were treated with chemerin (5, 10, and 20 ng/mL for 24 hours). Enzyme-linked immunosorbent assay (ELISA) was used to determine the secretion of inflammatory factors. Nuclear factor-κB (NF-κB) activation and p65 acetylation were evaluated by Western blot analysis. The expression and activity of sirtuin 1 (sirt1), a deacetylase act on p65, were also analyzed. The results showed that chemerin prompted inflammatory factors secretion, NF-κB activation and p65 acetylation through chemerin receptor 23 receptor. Chemerin constrained the expression and deacetylase activity of sirt1 through augment of reactive oxygen species (ROS) production. Additionally, chemerin exacerbated psoriasiform dermatitis in imiquimod-treated mice model. In conclusion, chemerin can seduce inflammatory response and promote NF-κB activation through inhibition of sirt1 activity by ROS production.  相似文献   
210.
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