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1.
摘要:目的 探讨纳米山药多糖双歧杆菌合生元结肠靶向微生态调节剂对菌群失调模型大鼠的免疫因子及SOD(超氧化物歧化酶)、MDA(丙二醛)、NO(一氧化氮)、MPO(髓过氧化物酶)表达的影响。方法 大鼠i.g盐酸林可霉素造成菌群失调伴有免疫缺陷肠炎模型,将大鼠随机分成靶向制剂组、阳性对照组和自然恢复组,紫外分光光度法检测结肠匀浆样本SOD、MDA、NO和MPO含量,微量溶血酶标仪分光光度法测定血清溶血素水平,ELISA法测定IL-1β(白细胞介素-1β)、IL-6(白细胞介素-6)、TNF-α(肿瘤坏死因子-α)、sIgA(分泌型免疫球蛋白A)及GM-CSF(粒细胞集落刺激生物因子)含量。结果 与自然恢复组相比,纳米山药多糖组显著提高大鼠溶血素水平及sIgA、GM-CSF和SOD含量(P<0.05),明显降低大鼠结肠样本中MDA、NO、MPO的含量(P<0.05),IL-1β、IL-6和TNF-α在大鼠血清中的表达均有不同程度的下降(P<0.05),且恢复到正常水平。结论 纳米山药多糖双歧杆菌合生元结肠靶向微生态调节剂能减轻肠道炎症,提高溶血素水平、sIgA和GM-CSF含量,降低IL-1β、IL-6和TNF-α含量,提高机体免疫能力,是理想的中药微生态调节剂。  相似文献   

2.
摘要:目的 探讨纳米山药多糖双歧杆菌合生元结肠靶向微生态调节剂对菌群失调模型大鼠的免疫因子及SOD(超氧化物歧化酶)、MDA(丙二醛)、NO(一氧化氮)、MPO(髓过氧化物酶)表达的影响。方法 大鼠i.g盐酸林可霉素造成菌群失调伴有免疫缺陷肠炎模型,将大鼠随机分成靶向制剂组、阳性对照组和自然恢复组,紫外分光光度法检测结肠匀浆样本SOD、MDA、NO和MPO含量,微量溶血酶标仪分光光度法测定血清溶血素水平,ELISA法测定IL-1β(白细胞介素-1β)、IL-6(白细胞介素-6)、TNF-α(肿瘤坏死因子-α)、sIgA(分泌型免疫球蛋白A)及GM-CSF(粒细胞集落刺激生物因子)含量。结果 与自然恢复组相比,纳米山药多糖组显著提高大鼠溶血素水平及sIgA、GM-CSF和SOD含量(P<0.05),明显降低大鼠结肠样本中MDA、NO、MPO的含量(P<0.05),IL-1β、IL-6和TNF-α在大鼠血清中的表达均有不同程度的下降(P<0.05),且恢复到正常水平。结论 纳米山药多糖双歧杆菌合生元结肠靶向微生态调节剂能减轻肠道炎症,提高溶血素水平、sIgA和GM-CSF含量,降低IL-1β、IL-6和TNF-α含量,提高机体免疫能力,是理想的中药微生态调节剂。  相似文献   

3.
目的:探讨氧化苦参碱(OMT)对冠脉结扎诱导的急性心肌梗死大鼠的保护作用与机制。方法:将SD大鼠随机分为4组:假手术组、假手术+OMT组、心梗模型组,OMT预处理组(ig给予OMT 100 mg/kg)。给药12小时后,结扎冠状动脉左前降支(LAD)复制大鼠急性心肌梗死模型。8小时后,取大鼠心肌组织,通过TUNEL染色观察大鼠心肌细胞损伤及凋亡情况;收集大鼠血清,检测LDH与CK水平,过氧化氢酶(CAT)、超氧化物岐化酶(SOD)、谷胱甘肽过氧化物酶(GSH)的活力,丙二醛(MDA)含量,ELISA法分析血清中IL-1β、IL-6和TNF-α的水平。结果:与假手术组比较,模型组大鼠的凋亡心肌细胞数明显增加(P0.05),血清CK、LDH水平显著升高(P0.05);同时,血清CAT、SOD与GSH的活性明显降低(P0.001),MDA的含量、IL-1β、IL-6和TNF-α水平显著增加(P0.001)。OMT预处理明显减轻了心肌梗死大鼠心肌细胞的损伤和凋亡,降低了其血清MDA含量,IL-1β、IL-6和TNF-α水平,增加了其CAT、SOD与GSH的活性。结论:氧化苦参碱预处理能够显著减轻心肌梗死大鼠的心肌损伤,这可能与其抗炎、抗凋亡与抗氧化损伤作用有关。  相似文献   

4.
目的:探讨绞股蓝总黄酮(total flaveos of Gymostemma pentaphyllum(Thunb)mak,TFG)对大鼠异丙肾上腺素诱导心肌缺血作用及其机理.方法:观测TFG对心肌组织p38MAPK表达及血清中SOD、MDA、LDH、NO、TNF-α等指标的影响.结果:TFG明显升高血清中SOD活性、NO含量; MDA含量下降; LDH活性降低,p38MAPK表达和血清TNF-α水平均明显下降.结论:TFG抗心肌缺血作用可能与下调心肌细胞p38MAPK的表达从而抑制TNF-α的产生、减轻心肌自由基损伤程度等有关.  相似文献   

5.
筛选铁皮石斛抗阿司匹林诱导急性胃黏膜损伤的活性组分,并探讨其抗胃粘膜损伤的作用。体外采用阿司匹林诱导人胃黏膜上皮GES-1细胞氧化应激损伤,铁皮石斛各组分预保护GES-1细胞24 h,MTS法检测细胞存活率,并通过比色法测定细胞上清液中乳酸脱氢酶LDH含量;体内采用阿司匹林建立SD大鼠急性胃黏膜损伤模型,灌胃给予铁皮石斛各组分,连续给药7 d后以溃疡指数评价铁皮石斛各组分抗阿司匹林致胃黏膜损伤作用,并通过测定胃液量、总酸度、胃蛋白酶活力、血清中一氧化氮(NO)、肿瘤坏死因子-α(TNF-α)、白介素-6(IL-6)以及胃组织中超氧化物歧化酶(SOD)、丙二醛(MDA)、前列腺素E2(PGE2),分析其可能的作用机制。结果表明,与模型组比较,铁皮石斛多糖组受损细胞活力显著升高,细胞上清液LDH含量显著降低,其它各组分细胞存活率及细胞上清液LDH含量与模型组无显著性差异;与模型组比较,铁皮石斛多糖组分显著降低胃溃疡模型大鼠的胃溃疡指数,抑制胃液分泌和胃酸含量及降低胃蛋白酶活性;与模型组比较,铁皮石斛多糖各组大鼠血清NO明显升高,TNF-α、IL-6显著降低,铁皮石斛多糖各组大鼠胃组织MDA水平明显降低,SOD、PGE2水平显著升高。铁皮石斛多糖有显著的抗阿司匹林诱导胃黏膜损伤作用。  相似文献   

6.
目的探讨纳米山药多糖双歧杆菌合生元结肠靶向微生态调节剂对菌群失调模型大鼠的免疫因子及SOD(超氧化物歧化酶)、MDA(丙二醛)、NO(一氧化氮)、MPO(髓过氧化物酶)表达的影响。方法大鼠i.g盐酸林可霉素造成菌群失调伴有免疫缺陷肠炎模型,将大鼠随机分成靶向制剂组、阳性对照组和自然恢复组,紫外分光光度法检测结肠匀浆样本SOD、MDA、NO和MPO含量,微量溶血酶标仪分光光度法测定血清溶血素水平,ELISA法测定IL-1β(白细胞介素-1β)、IL-6(白细胞介素-6)、TNF-α(肿瘤坏死因子-α)、sIgA(分泌型免疫球蛋白A)及GM-CSF(粒细胞集落刺激生物因子)含量。结果与自然恢复组相比,纳米山药多糖组显著提高大鼠溶血素水平及sIgA、GM-CSF和SOD含量(P0.05),明显降低大鼠结肠样本中MDA、NO、MPO的含量(P0.05),IL-1β、IL-6和TNF-α在大鼠血清中的表达均有不同程度的下降(P0.05),且恢复到正常水平。结论纳米山药多糖双歧杆菌合生元结肠靶向微生态调节剂能减轻肠道炎症,提高溶血素水平、sIgA和GM-CSF含量,降低IL-1β、IL-6和TNF-α含量,提高机体免疫能力,是理想的中药微生态调节剂。  相似文献   

7.
目的:探讨昆布(海带)在实验性高脂血症大鼠中的降血脂作用和机制。方法:健康雌性Wistar大鼠40只,应用高脂饲料喂养方法建立高脂血症动物模型,海带粉饲料喂养干预治疗。生化法检测大鼠血清甘油三酯(TG)、总胆固醇(TC)、低密度脂蛋白(LDL)和高密度脂蛋白(HDL)水平。硫代巴比妥酸法和硝酸还原酶法分别检测脂质过氧化物丙二醛(MDA)和一氧化氮(NO)含量,黄嘌呤氧化酶法和化学比色法分别测定超氧化物歧化酶(SOD)和谷胱甘肽过氧化物酶(GSH-PX)活性。结果:经海带干预治疗后,动物血清TG、TC和LDL水平较模型组显著降低、HDL水平显著升高(P〈0.05)。治疗组动物血清和肝组织MDA和NO水平显著低于、而SOD和GSH-PX活性均显著高于模型组(P〈0.05)。结论:海带可能影响TG、TC、LDL和HDL等组分的代谢,通过增强抗氧化SOD和GSH-PX的活性,降低体内MDA和NO的水平,发挥调节血脂水平的作用。  相似文献   

8.
本实验探讨藏药莪达夏对大鼠急性心肌缺血再灌注损伤的抗氧化保护作用。采用结扎大鼠冠脉左前降支方法造成心肌缺血再灌注模型,测定再灌注40 min后血清中乳酸脱氢酶(LDH)、肌酸激酶(CK)、超氧化物歧化酶(SOD)、谷肤甘肤过氧化物酶(GSH-Px)活性以及MDA含量。实验结果显示莪达夏可以显著降低心肌缺血再灌注后血清CK、LDH和MDA含量,升高血清SOD和GSH-Px活力(P0.01,P0.05)。表明藏药莪达夏对缺血-再灌注心肌损伤有抗氧化保护作用。  相似文献   

9.
目的: 探讨蒙药绍沙-7味丸对心肌缺血/再灌注损伤大鼠的防治作用及机制。方法: 60只大鼠随机分成6组:假手术组、模型组、蒙药绍沙-7味丸低、中、高剂量组以及阳性药对照组,每组10只;蒙药绍沙-7味丸低、中、高剂量组分别灌胃0.4 g/kg、0.8 g/kg、1.6 g/kg蒙药绍沙-7味丸,阳性药对照组灌胃0.3 g/kg复方丹参片,假手术组和模型组灌胃2 ml/100 g蒸馏水,均连续灌胃15 d,1次/日;15 d后,模型组及治疗组大鼠开胸结扎冠状动脉30 min后,解开结扎线行再灌注120 min后关闭胸腔处理;6组大鼠术后行心电图检查后处死大鼠取心脏行HE染色、TTC染色,观察梗死面积及病理变化。ELISA法检测血清中cTnI、CK-MB、 LDH、MDA、SOD、GSH-PX及TNF-α、IL-18、IL-6、IL-1β的水平,免疫组化法检测心肌组织NF-кB水平。结果: 与假手术组相比,心肌缺血/再灌注损伤大鼠心肌梗死面积增大,同时血清中cTnI、CK-MB、 LDH、MDA、GSH-PX及TNF-α、IL-18、IL-6、IL-1β的含量明显增加(P<0.01),SOD的含量则明显降低(P<0.01),心脏组织中的NF-кB水平增加;与心肌缺血/再灌注损伤大鼠相较,蒙药绍沙-7味丸改善大鼠心律失常现象及病理变化,减少梗死面积;血清中cTnI、CK-MB、 LDH、MDA、GSH-PX及TNF-α、IL-18、IL-6、IL-1β的含量明显降低(P<0.01),SOD的含量明显增加(P<0.01),心脏组织中的NF-кB水平降低。结论: 蒙药绍沙-7味丸可有效缓解大鼠心肌缺血/再灌注损伤,其作用与氧化应激和凋亡相关。  相似文献   

10.
摘要:目的 探讨纳米山药多糖双歧杆菌合生元结肠靶微生态调节剂对菌群失调模型大鼠的免疫因子及超氧化物歧化酶(SOD)、丙二醛(MDA)、一氧化氮(NO)、髓过氧化物酶(MPO)表达的影响。方法 大鼠i.g盐酸林可霉素造成菌群失调伴有免疫缺陷肠炎模型,将大鼠随机分成靶向制剂组、阳性对照组和自然恢复组,紫外分光光度法检测结肠匀浆样本SOD、MDA、NO和MPO含量,微量溶血酶标仪分光光度法测定血清溶血素水平,ELISA法测定IL-1β、IL-6、TNF-α、sIgA及GM-CSF含量。结果 与自然恢复组相比,纳米山药多糖组显著提高大鼠溶血素水平(0.406±0.0122 vs 00.267±0.0138)、sIgA(51.64±4.21 vs 35.26±3.05)和SOD(13.400±0.255 vs 6.250±0.144)含量(t=14.14,t=8.351,t=31.68,P<0.05),明显降低大鼠结肠样本中MDA(1.255±0.082 vs 22.070±0.080)、NO(1.520±0.112 vs 3.260±0.134)和MPO(0.520±0.065 vs 1.110±0.218)的含量(t=59.61,t=26.02,t=6.351,P<0.05),L-1β(65.23±3.09 vs 119.67±9.97)、IL-6(156.67±3.91 vs 225.46±3.60)、TNF-α(30.56±5.60 vs 1.110±0.218)和GM-CSF(125.615±4.164 vs 205.99±3.45)在大鼠血清中的表达均有不同程度的明显的的下降(t=12.77,t=31.68,t=8.29,t=28.88,P<0.05),且恢复到正常水平。结论 纳米山药多糖双歧杆菌合生元结肠靶微生态调节剂能减轻肠道炎症,提高溶血素水平、sIgA和GM-CSF含量,降低IL-1β、IL-6、TNF-α含量,提高机体免疫能力,是理想的中药微生态调节剂。  相似文献   

11.
To study how conserved fundamental concepts of the heat stress response (HSR) are in photosynthetic eukaryotes, we applied pharmaceutical and antisense/amiRNA approaches to the unicellular green alga Chlamydomonas reinhardtii. The Chlamydomonas HSR appears to be triggered by the accumulation of unfolded proteins, as it was induced at ambient temperatures by feeding cells with the arginine analog canavanine. The protein kinase inhibitor staurosporine strongly retarded the HSR, demonstrating the importance of phosphorylation during activation of the HSR also in Chlamydomonas. While the removal of extracellular calcium by the application of EGTA and BAPTA inhibited the HSR in moss and higher plants, only the addition of BAPTA, but not of EGTA, retarded the HSR and impaired thermotoler- ance in Chlamydomonas. The addition of cycloheximide, an inhibitor of cytosolic protein synthesis, abolished the attenu- ation of the HSR, indicating that protein synthesis is necessary to restore proteostasis. HSP90 inhibitors induced a stress response when added at ambient conditions and retarded attenuation of the HSR at elevated temperatures. In addition, we detected a direct physical interaction between cytosolic HSP90A/HSP70A and heat shock factor 1, but surprisingly this interaction persisted after the onset of stress. Finally, the expression of antisense constructs targeting chloroplast HSP70B resulted in a delay of the cell's entire HSR, thus suggesting the existence of a retrograde stress signaling cascade that is desensitized in HSP7OB-antisense strains.  相似文献   

12.
To accommodate two seemingly contradictory biological roles in plant physiology, providing both the rigid structural support of plant cells and the adjustable elasticity needed for cell expansion, the composition of the plant cell wall has evolved to become an intricate network of cellulosic, hemicellulosic, and pectic polysaccharides and protein. Due to its complexity, many aspects of the cell wall influence plant cell expansion, and many new and insightful observations and technologies are forthcoming. The biosynthesis of cell wall polymers and the roles of the variety of proteins involved in polysaccharide synthesis continue to be characterized. The interactions within the cell wall polymer network and the modification of these interactions provide insight into how the plant cell wall provides its dual function. The complex cell wall architecture is controlled and organized in part by the dynamic intracellular cytoskeleton and by diverse trafficking pathways of the cell wall polymers and cell wall-related machinery. Meanwhile, the cell wall is continually influenced by hormonal and integrity sensing stimuli that are perceived by the cell. These many processes cooperate to construct, maintain, and manipulate the intricate plant cell wall--an essential structure for the sustaining of the plant stature, growth, and life.  相似文献   

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14.
Proper vesicle tethering and membrane fusion at the cell plate are essential for cytokinesis. Both the vesicle tethering complex exocyst and membrane fusion regulator KEULE were shown to function in cell plate formation, but the exact mechanisms still remain to be explored. In this study, using yeast two-hybrid (Y-2-H) assay, we found that SEC6 interacted with KEULE, and that a small portion of C-terminal region of KEULE was required for the interaction. The direct SEC6-KEULE interaction was supported by further studies using in vitro pull-down assay, immunoprecipitation, and in vivo bimolecular florescence complementation (BIFC) microscopy, sec6 mutants were male gametophytic lethal as reported; however, pollen-rescued sec6 mutants (PRsec6) displayed cytokinesis defects in the embryonic cells and later in the leaf pavement cells and the guard cells. SEC6 and KEULE proteins were co-localized to the cell plate during cytokine- sis in transgenic Arabidopsis. Furthermore, only SEC6 but not other exocyst subunits located in the cell plate interacted with KEULE in vitro. These results demonstrated that, like KEULE, SEC6 plays a physiological role in cytokinesis, and the SEC6-KEULE interaction may serve as a novel molecular linkage between arriving vesicles and membrane fusion machin- ery or directly regulate membrane fusion during cell plate formation in plants.  相似文献   

15.
Pollution of the aquatic environment is an ever-growing problem, as waters are the ultimate sink for the large number of xenobiotics from multiple sources. DNA damaging agents have a significant ecological relevance since they are implicated in many pathological processes and exert effects beyond that of individual being active through following generations. A large number of methods have been applied to evaluate genotoxic damage in different aquatic species. Comet assay, as method for de- tecting DNA alterations, and micronucleus test, as an index of chromosomal damage are the most widely applied and validated methods in field studies. These methods were applied in different vertebrate and invertebrate aquatic species, but only mollusk and fish species have been employed in routine biomonitoring programs. Mussels, due to their widely geographical distribution and the suitability for caging represent the bioindicator of choice in field studies. Mytilus species is the most used marine mussel. The use of fish is limited to specific geographic areas. The present review mainly focuses on the application of comet assay and micronucleus test in mussels. A number of biomonitoring studies in mussels, using comet assay or micronucleus test, revealed exposure to different classes of genotoxic compounds with a good discrimination power. The different evidence from the two as- says, reflects different biological mechanisms for the two genetic endpoints, DNA damage and chromosomal damage, suggesting their combined application in the field. Different endogenous and exogenous factors have been shown to modulate the genotoxic responses in mussels, acting as confounding factors in environmental monitoring. The use of standardized protocol for caging, sampling and genotoxity evaluation is critical in biomonitoring studies. The use of a multimarker approach coupling genotoxicity biomarkers with physiological and biochemical factors allows to have a complete picture of the environmental pollution [Current Zoology 60 (2): 273-284, 2014].  相似文献   

16.
The pH of intracellular compartments is essential for the viability of cells. Despite its relevance, little is known about the pH of these compartments. To measure pH in vivo, we have first generated two pH sensors by combining the improved-solubility feature of solubility-modified green fluorescent protein (GFP) (smGFP) with the pH-sensing capabil- ity of the pHluorins and codon optimized for expression in Arabidopsis. PEpHluorin (plant-solubility-modified ecliptic pHluorin) gradually loses fluorescence as pH is lowered with fluorescence vanishing at pH 6.2 and PRpHluorin (plant- solubility-modified ratiomatric pHluorin), a dual-excitation sensor, allowing for precise measurements. Compartment- specific sensors were generated by further fusing specific sorting signals to PEpHluorin and PRpHluorin. Our results show that the pH of cytosol and nucleus is similar (pH 7.3 and 7.2), while peroxisomes, mitochondrial matrix, and plastidial stroma have alkaline pH. Compartments of the secretory pathway reveal a gradual acidification, spanning from pH 7.1 in the endoplasmic reticulum (ER) to pH 5.2 in the vacuole. Surprisingly, pH in the trans-Golgi network (TGN) and mul- tivesicular body (MVB) is, with pH 6.3 and 6.2, quite similar. The inhibition of vacuolar-type H+-ATPase (V-ATPase) with concanamycin A (ConcA) caused drastic increase in pH in TGN and vacuole. Overall, the PEpHluorin and PRpHluorin are excellent pH sensors for visualization and quantification of pH in vivo, respectively.  相似文献   

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Citrate synthase has a key role in the tricarboxylic (TCA) cycle of mitochondria of all organisms, as it cata- lyzes the first committed step which is the fusion of a carbon-carbon bond between oxaloacetate and acetyl CoA. The regulation of TCA cycle function is especially important in plants, since mitochondrial activities have to be coordinated with photosynthesis. The posttranslational regulation of TCA cycle activity in plants is thus far almost entirely unexplored. Although several TCA cycle enzymes have been identified as thioredoxin targets in vitro, the existence of any thioredoxin-dependent regulation as known for the Calvin cycle, yet remains to be demonstrated. Here we have investigated the redox regulation of the Arabidopsis citrate synthase enzyme by site-directed mutagenesis of its six cysteine residues. Our results indicate that oxidation inhibits the enzyme activity by the formation of mixed disulfides, as the partially oxidized citrate synthase enzyme forms large redox-dependent aggregates. Furthermore, we were able to demonstrate that thioredoxin can cleave diverse intraas well as intermolecular disulfide bridges, which strongly enhances the activity of the enzyme. Activity measurements with the cysteine variants of the enzyme revealed important cysteine residues affecting total enzyme activity as well as the redox sensitivity of the enzyme.  相似文献   

19.
Reactive oxygen species and auxin play important roles in the networks that regulate plant development and morphogenetic changes, However, the molecular mechanisms underlying the interactions between them are poorly understood. This study isolated a mas (More Axillary Shoots) mutant, which was identified as an allele of the mitochondrial AAA-protease AtFtSH4, and characterized the function of the FtSH4 gene in regulating plant development by medi- ating the peroxidase-dependent interplay between hydrogen peroxide (H2Oz) and auxin homeostasis. The phenotypes of dwarfism and increased axillary branches observed in the mas (renamed as ftsh4-4) mutant result from a decrease in the IAA concentration. The expression levels of several auxin signaling genes, including IAA1, IAA2, and IAA3, as well as several auxin binding and transport genes, decreased significantly in ftsh4-4 plants. However, the H202 and peroxidases levels, which also have IAA oxidase activity, were significantly elevated in ftsh4-4 plants. The ftsh4-4 phenotypes could be reversed by expressing the iaaM gene or by knocking down the peroxidase genes PRX34 and PRX33. Both approaches can increase auxin levels in the ftsh4-4 mutant. Taken together, these results provided direct molecular and genetic evidence for the interaction between mitochondrial ATP-dependent protease, H2O2, and auxin homeostasis to regulate plant growth and development.  相似文献   

20.
The choice of a suitable species to translate pollution signals into a quantitative monitor is a fundamental step in biomonitoring plans. Here we present the results of three years of biomonitoring at a new coal power plant in central Italy using three different aquatic and terrestrial wildlife species in order to compare their reliability as sentinel organisms for genotoxicity. The comet assay was applied to the common land snail Helix spp., the lagoon fish Aphaniusfasciatus, and the green frog Rana esculenta sampled in the area potentially exposed to the impact of the power station. The tissue concentration of some expected pollutants (As, Cd, Ni, Pb, Cr) was analysed in parallel samples collected in the same sampling sites. The three species showed different values in the comet assay (Tail Intensity) and different accumulation profiles of heavy metals. Aphanius fasciatus showed an increasing genotoxic effect over time that paralleled the temporal increase of the heavy metals, especially arsenic, and the highest correlation between heavy metals and DNA damage. Helix spp. showed levels of damage inversely related to the distance from the source of pollution and in partial accordance with the total accumulation of trace elements. On the contrary, Rana esculenta showed a low capability to accumulate metals and had inconsistent results in the comet test. The fish appeared to be the most efficient and sensitive species in detecting chemical pollution. Overall, both the fish and the snail reflected a trend of increasing pollution in the area surrounding the power plant across time and space [Current Zoology 60 (2): 308-321, 2014].  相似文献   

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