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61.
62.
WANG Jing LI Zhenxing PAVASE Ramesh Tushar LIN Hong ZOU Long WEN Jie LV Liangtao 《中国海洋大学学报(英文版)》2016,15(4):690-696
Advanced glycation endproducts(AGEs) have been recognized as hazards in processed foods that can induce chronic diseases such as cardiovascular disease, diabetes, and diabetic nephropathy. In this study, we investigated the AGEs contents of 35 types of industrial seafood products that are consumed frequently in eastern China. Total fluorescent AGEs level and Nε-carboxymethyl-lysine(CML) content were evaluated by fluorescence spectrophotometry and gas chromatography-mass spectrometry(GC-MS), respectively. The level of total fluorescent AGEs in seafood samples ranged from 39.37 to 1178.3 AU, and was higher in canned and packaged instant aquatic products that were processed at high temperatures. The CML content in seafood samples ranged from 44.8 to 439.1 mg per kg dried sample, and was higher in roasted seafood samples. The total fluorescent AGEs and CML content increased when seafood underwent high-temperature processing, but did not show an obvious correlation. The present study suggested that commonly consumed seafood contains different levels of AGEs, and the seafood processed at high temperatures always displays a high level of either AGEs or CML. 相似文献
63.
The culture of Sertoli cells has become an indispensable resource in studying spermatogenesis. A new Sertoli cell line (POSC) that consisted predominantly of fibroblast-like cells was derived from the testis of the olive flounder Paralichthys olivaceus and sub-cultured for 48 passages. Analysis of the mtDNA COI gene partial sequence confirmed that the cell line was from P. olivaceus. Cells were optimally maintained at 25°C in DMEM/F12 medium supplemented with fetal bovine serum, basic fibroblast growth factor, and epidermal growth factor. The growth curve of POSC showed a typical “S” shape. Chromosome analysis revealed that the cell line possessed the normal P. olivaceus diploid karyotype of 2n=48t. POSC expressed dmrt1 but not vasa, which was detected using RT-PCR and sequencing. Immunocytochemistry revealed that the cells exhibited the testicular Sertoli cell marker FasL. Therefore, POSC appeared to consist of testicular Sertoli cells. Bright fluorescent signals were observed after the cells were transfected with pEGFP-N3 plasmid, with the transfection efficiency reaching 10%. This research not only offers an ideal model for further gene expression and regulation studies on P. olivaceus, but also serves as valuable material in studying fish spermatogenesis, Sertoli cell-germ cell interactions, and the mechanism of growth and development of testis. 相似文献
64.
山东省曹县地区土壤地球化学调查是按浅层土壤样品1点/4 km~2,深层土壤样品1点/16 km~2。测试N,P,K,Cu,Zn,B,Mo,Mn,F,As,Hg,Pb,Cr,Cd等14种指标。在统计这些指标的表层、深层土壤地球化学特征参数的基础上,对其与世界、全省同类参数的差异进行了分析,并分析了区内表层、深层土壤元素含量的相关性,认为该区表层土壤元素含量的显著特征是高F而低P,Zn,Mo。大部分元素在表层土壤中的含量继承了土壤母质的成分特征,但N,P,F,Hg等受人为活动和污染源的作用在表层土壤中明显富集。 相似文献
65.
A new record of a flathead fish (Teleostei: Platycephalidae) from China based on morphological characters and DNA barcoding 总被引:2,自引:0,他引:2
A new record of Platycephalus sp.1 (sensu Nakabo, 2002) was documented based on morphological characters and DNA barcoding. We collected 174 specimens of the genus Platycephalus from Chinese coastal waters of Dongying, Qingdao, Zhoushan, and Beihai. Samples were identified as Platycephalus sp.1 morphologically. The coloration, meristic traits, and morphometric measurements are consistent with previously published records. In brief, it is an orange-brown flathead fish with dark brown spots scattered on head and body, lateral line scales 83 to 99 with one or two spine-bearing anteriormost pored scale, no yellow blotch on the caudal fin. Cytochrome oxidase I subunit (COI) gene fragments were sequenced for phylogenetic analysis. The mean evolutionary distance within the species Platycephalus sp.1 was 0.1%. Net evolutionary distances between Platycephalus sp.1 and other species of Platycephalus ranged from 10.8% to 19.7%, which is much greater than the threshold for species delimitation. The COI sequence analysis strongly supports the validity of Platyceohalus sp.1 at genetic level. 相似文献
66.
Xueying Jia Zhijie Tian Lei Qin Linlin Zhang Yuanchun Zou Ming Jiang Xianguo Lyu 《中国地理科学(英文版)》2018,28(2):337-352
Iron-rich groundwater flowing into wetlands is a worldwide environmental pollution phenomenon that is closely associated with the stability of wetland ecosystems. Combined with high phosphorus(P) loading from agricultural runoff, the prediction of the evolution of wetland vegetation affected by compound contamination is particularly urgent. We tested the effects of anaerobic iron-rich groundwater discharge in a freshwater marsh by simulating the effect of three levels of eutrophic water on native plants(Glyceria spiculosa(Fr. Schmidt.) Rosh.). The management of wetland vegetation with 1–20 mg/L Fe input is an efficient method to promote the growth of plants, which showed an optimum response under a 0.10 mg/L P surface water environment. Iron-rich groundwater strongly affects the changes in ecological niches of some wetland plant species and the dominant species. In addition, when the P concentration in a natural body of water is too high, the governance effect of eutrophication might not be as expected. Under iron-rich groundwater conditions, the δ~(13)C values of organs were more depleted, which can partially explain the differences in δ~(13)C in the soil profile. Conversely, the carbon isotope composition of soil organic carbon is indicative of past changes in vegetation. The results of our experiments confirm that iron-rich groundwater discharge has the potential to affect vegetation composition through toxicity modification in eutrophic environments. 相似文献
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68.
中巴经济走廊是"一带一路"建设的旗舰项目,对中巴经济走廊地质灾害进行敏感性分析与区划,可为中巴经济走廊地质灾害的防治提供参考。基于此,文章选取高程、坡度、地形起伏度、地震密度、多年平均降雨量、距断裂带的距离、地层岩性、距河流的距离和距公路的距离等9个指标,采用加权信息量模型和证据权法,综合分析中巴经济走廊地质灾害敏感性。并运用ROC曲线验证对比两种模型分析的敏感性结果,选取精度较高的模型分析的地质灾害敏感性进行研究区区划,最后对区划结果进行相关验证。研究结果表明:1)中巴经济走廊容易诱发地质灾害的条件为:高程在2660~3470 m之间,坡度为29°~35°,地形起伏度在45~70 m之间,地震密度在2~4个/102 km2之间,多年平均降雨量在430~530 mm之间,距断裂带距离小于5 km,地层岩性为软岩和极软岩,距河流距离小于2 km,距公路距离小于2 km。2)基于加权信息量模型和证据权法分析的中巴经济走廊地质灾害敏感性精度分别为0.821和0.795,表明本研究选取的地质灾害敏感性分析模型具有较高的准确性,但是运用加权信息量模型分析的敏感性更符合实际情况。因此,运用加权信息量模型分析的结果进行研究区地质灾害敏感性区划。3)研究区地质灾害不敏感区、低敏感区、中等敏感区、高度敏感区和极高敏感区所占面积比分别为26.3%、23.1%、21.6%、18.8%和10.2%,以中、低敏感性为主;且敏感性呈现出南低北高的空间分布特征。4)运用实地调研的地质灾害点对本文区划的中巴经济走廊地质灾害敏感性结果验证,表明区划的结果具有一定的科学、可信性,可以为中巴经济走廊重大工程建设、交通线路选线、城市规划、资源开发等方面提供科学依据。 相似文献
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70.
The Zoige Basin is located in the eastern margin of the Qinghai-Xizang Plateau, in which two cores, RH and RM, have been drilled,
with the depths of 120 m and 310 m respectively. The former with the bottom age of 826 kaB. P. has been divided into 21 stages
according to the multi-proxy analysis, which could be basically compared with the oxygen isotope record of deep-sea core.
The palaeoclimatic and palaeoenvironmental process of the Zoigê Basin over the past 900 kaB. P. is reconstructed, and the
comparison of core RH with the Luochuan Loess record is made. 相似文献