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奇楠沉香叶的有效成分含量测定及其生物活性评价 被引量:2
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作者 林思琦 招志辉 司徒杰 《广州中医药大学学报》 CAS 2023年第5期1239-1247,共9页
【目的】测定不同提取条件下奇楠沉香叶中总黄酮、总多糖、鞣质的含量及其体外抗氧化、抗菌、抗炎活性,同时探讨其相关性。【方法】(1)采用水提法、醇提法,每次加入12倍量的水/70%乙醇对奇楠沉香叶进行加热回流提取,2 h/次,提取2次。(2... 【目的】测定不同提取条件下奇楠沉香叶中总黄酮、总多糖、鞣质的含量及其体外抗氧化、抗菌、抗炎活性,同时探讨其相关性。【方法】(1)采用水提法、醇提法,每次加入12倍量的水/70%乙醇对奇楠沉香叶进行加热回流提取,2 h/次,提取2次。(2)以芦丁、D-无水葡萄糖、没食子酸为指标成分,采用紫外-可见分光光度法结合化学显色法测定奇楠沉香叶水提物、70%醇提物中总黄酮、总多糖、鞣质的含量。(3)以抗坏血酸(VC)为阳性对照,采用紫外-可见分光光度法测定奇楠沉香叶水提物、70%醇提物对1,1-二苯基-2-三硝基苯肼自由基(DPPH·)、2,2’-联氮-双(3-乙基苯并噻唑啉-6-磺酸)自由基(ABTS+·)、羟自由基(·OH)、超氧阴离子自由基(O)的半数抑制浓度(IC50)以及对铁离子(Fe3+)的还原能力。(4)采用微量稀释法测定奇楠沉香叶水提物、70%醇提物对金黄色葡萄球菌、表皮葡萄球菌、肺炎克雷伯菌、铜绿假单胞菌、变形杆菌、沙门氏菌、福氏痢疾杆菌、大肠杆菌的最低抑菌浓度(MIC)。(5)采用耳廓肿胀法测定高、中、低剂量奇楠沉香叶水提物组,高、中、低剂量70%醇提物组(3.33、1.67、0.83 g生药/kg)二甲苯所致小鼠耳廓的肿胀度。【结果】(1)奇楠沉香叶水提物、70%醇提物中的总黄酮、总多糖、鞣质含量依次为:(5.04±0.01)%、(3.78±0.02)%,(6.86±0.11)%、(3.09±0.27)%,(2.16±0.01)%、(1.81±0.01)%。(2)奇楠沉香叶水提物、70%醇提物对DPPH·、ABTS+·、·OH、O的IC50依次为0.31、0.37 mg/mL,0.12、0.16 mg/mL,0.069、0.074 mg/mL,0.71、1.17 mg/mL;同时随着浓度的增加均对Fe3+的还原性增强。(3)奇楠沉香叶水提物、70%醇提物对金黄色葡萄球菌、表皮葡萄球菌、肺炎克雷伯菌、铜绿假单胞菌、变形杆菌、沙门氏菌、福氏痢疾杆菌、大肠杆菌的MIC范围依次为15.63~>500.0、31.25~>500.0 mg/mL。(4)与空白组比较,高、中剂量奇楠沉香叶水提物组,高、中剂量70%醇提物组小鼠耳廓肿胀度显著降低(P<0.01),但相同剂量水提物组与70%醇提物组相比则无显著性差异(P>0.05)。【结论】奇楠沉香叶中含有较多的总黄酮、总多糖和鞣质成分,同时具有较强的抗氧化、抗菌、抗炎活性,且成分含量与生物活性基本呈正相关性。相比醇提法,水提法制备的奇楠沉香叶提取物具有更多的有效成分和更强的生物活性。 展开更多
关键词 奇楠沉香叶 总黄酮 总多糖 鞣质 抗氧化 抗菌 抗炎 水提法 醇提法
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Overexpression of Proline Transporter Gene Isolated from Halophyte Confers Salt Tolerance in Arabidopsis 被引量:16
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作者 沈义国 张万科 +3 位作者 阎冬青 杜保兴 张劲松 陈受宜 《Acta Botanica Sinica》 CSCD 2002年第8期956-962,共7页
Proline is one of the most important and widespread osmolyte which functions in adaptation to adverse environmental stresses in many organisms. Also it is an important carbon and nitrogen resource in higher plants. Me... Proline is one of the most important and widespread osmolyte which functions in adaptation to adverse environmental stresses in many organisms. Also it is an important carbon and nitrogen resource in higher plants. Metabolism of proline has been elucidated in many plant species. However, transport of proline was poorly characterized although transport system plays an important role in proline distribution in different tissues. We isolated one full_length cDNA encoding proline transporter from the typical halophyte: Atriplex hortensis L. through cDNA library screening and 5′_RACE. The deduced amino acid sequence had eleven transmembrane domains, showed 60%-69% similarities to other ProTs and the gene was designated AhProT1. In the phylogenetic tree, higher plants' ProTs, e.g. AhProT1, showed more similar to ProP from microorganisms than ProT from mammalians. AhProT1 gene was transformed into Arabidopsis thaliana under 35S promoter. In MS medium containing [U_ 14 C] proline, AhProT1 + plants were able to accumulate much more radiolabeled proline in the roots than control plants. In MS medium containing different concentrations of NaCl, AhProT1 + plants could endure 200 mmol/L NaCl and keep development and biomass increase with proline supply, whereas control plants died back at 150 mmol/L NaCl. 展开更多
关键词 Atriplex hortensis proline transporter deposition salt stress
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Chemical composition and anti-MRSA activity of the essential oil from Chinese eaglewood 被引量:14
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作者 梅文莉 曾艳波 +2 位作者 吴娇 崔海滨 戴好富 《Journal of Chinese Pharmaceutical Sciences》 CAS 2008年第3期225-229,共5页
To analyze the constituents of essential oil from Chinese eaglewood [resinous wood of Aquilaria sinensis (Lour.) Gilg] and its anti-methicillin-resistant Staphylococcus aureus (MRSA) activity. The essential oil wa... To analyze the constituents of essential oil from Chinese eaglewood [resinous wood of Aquilaria sinensis (Lour.) Gilg] and its anti-methicillin-resistant Staphylococcus aureus (MRSA) activity. The essential oil was extracted by water-steam distillation and analyzed by GC/MS method. The relative contents of the compounds were determined by normalization. The compounds were characterized by NIST05 and WILEY275L database matching and comparison of their MS spectra with those of literature data. Antibacterial activity of the oil was assayed by the filter paper disc agar diffusion method. The oil showed significant antibacterial activity against MRSA. Sixty-six chromatographic peaks were detected, among them thirty compounds comprising 59.80% of the total essential oil were characterized. Twenty-six compounds comprising 54.26% of the oil were identified as sesquiterpenes. β-Agarofuran (8.96%), kusunol (7.82%), (-)-jinkoh-eremol (5.04%), agarospirol (4.53%), baimuxifuranic acid (4.09%) were the major sesquiterpenes. Four nor-sesquiterpenes and some other sesquiterpenes, such as 10-epi-γ-eudesmol, α-agarofuran, epi-ligulyl oxide, etc. were detected in Chinese eaglewood oil for the first time. This is the first report about anti-MRSA activity of Chinese eaglewood oil from A. sinensis. 展开更多
关键词 Chinese eaglewood Aquilaria sinensis Lour. Gilg Essential oil GC/MS Antibacterial activity MRSA
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急性矽肺 被引量:1
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作者 陈开璋 《工业卫生与职业病》 CAS 1985年第2期115-118,共4页
急性矽肺多见于通风防尘设备差,矽尘危害严重的工种。其特点是接尘时间短,症状快速发作且严重,多数预后不良。由于其临床、X线和病理等与一般矽肺有所不同,易被误诊,为引起注意,本文对该病作一综述。
关键词 急性矽肺 白沉 泡蛋 肺泡 矽结节 矽尘 矽肺病 硅肺病
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A Comparative Study on Three Methods for the Extraction of Total RNA from Pinus bungeana 被引量:3
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作者 王雁 李贞 +3 位作者 刘小侠 倪慧 毛红 张青文 《Agricultural Science & Technology》 CAS 2011年第5期663-665,共3页
[Objective] The aim of this study was to compare three RNA extraction methods and thus find out the suitable one for isolating intact and high quality total RNA from Pinus bungeana.[Method] Employing three extraction ... [Objective] The aim of this study was to compare three RNA extraction methods and thus find out the suitable one for isolating intact and high quality total RNA from Pinus bungeana.[Method] Employing three extraction methods of Trizol,RNeasy Mini Kit,LiCl precipitation,total RNAs of P.bungeana were extracted from pine leaf samples,and their integrity and purity were detected via agarose gel electrophoresis and spectrophotometry for a comparative study.[Result] Among the three extraction methods,LiCl precipitation method demonstrated higher yield and better integrity of total extracted RNA,with OD260/OD280 ratio between 1.8-2.0 and clear 28 S and 18 S bands in electrophoresis pattern.[Conclusion] LiCl precipitation method could be used to extract highly pure and intact total RNA from P.bungeana. 展开更多
关键词 Pinus bungeana Total RNA Extraction method cDNA library
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Grain-size Characteristics of Sediment in Daniugou Peatland in Changbai Mountains,Northeast China:Implications for Atmospheric Dust Deposition 被引量:5
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作者 BAO Kunshan JIA Lin +1 位作者 LU Xianguo WANG Guoping 《Chinese Geographical Science》 SCIE CSCD 2010年第6期498-505,共8页
The grain-size distribution characteristics and grain-size parameters of sediment in two vertical sections of Daniugou peatland in the Changbai Mountains were systematically investigated.A comparative analysis of the ... The grain-size distribution characteristics and grain-size parameters of sediment in two vertical sections of Daniugou peatland in the Changbai Mountains were systematically investigated.A comparative analysis of the sediment granularity using a discriminative function with Hongyuan peat,red clay,loess-paleosol,fluvial deposit as well as lacustrine deposit was also conducted.It turns out that the vertical section of Daniugou peat ash is primarily constituted by clay and silt particles,and the content of sand is relatively small.Grain-size frequency curves generally show a single-peak modality while a bimodal pattern is detected in the upper layer.The grain-size component and peak pattern of grain-size frequency curves also illustrate that peat ash materials were transported to the peatland by long-range aeolian dust during the deposition process,while there existed short-distance dust influence in peat deposition of the upper layer.Comparisons of grain-size parameters and the discriminative Y-value of Daniugou peat ash with those of typical aeolian sediments show close similarities,suggesting the possibility that atmospheric dust transport processes were involved in the accumulation of peat again.Moreover,the variations of grain-size distribution suggest the local environmental deterioration which is just the driving force of local dust elevation.Grain-size analysis of peatland sediment is demonstrated to be one effective method to extract information about regional and global environmental evolution,and more attention should be paid to current local ecological environment and to seeking a balance between economic development and environmental protection in Northeast China. 展开更多
关键词 GRAIN-SIZE PEATLAND aeolian sediment atmospheric dust deposition Changbai Mountains
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EFFECTS OF SIMVASTAIN COMBINED WITH OMEGA-3 FATTY ACIDS ON HIGH SENSITIVE C-REACTIVE PROTEIN, LIPIDEMIA, ANDFIBRINOLYSIS IN PATIENTS WITH MIXED DYSLIPIDEMIA 被引量:1
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作者 HengHong Zhi-minXu +5 位作者 Bao-senPang LiangCui YuWei Wen-jingGuo Yan-lingMao Xin-chunYang 《Chinese Medical Sciences Journal》 CAS CSCD 2004年第2期145-149,共5页
Objective To evaluate the effects of simvastatin combined with omega-3 fatty acids on high sensitive C-reactive protein(HsCRP), lipidemia, and fibrinolysis in coronary heart disease (CHD) and CHD risk equivalent patie... Objective To evaluate the effects of simvastatin combined with omega-3 fatty acids on high sensitive C-reactive protein(HsCRP), lipidemia, and fibrinolysis in coronary heart disease (CHD) and CHD risk equivalent patients with mixed dyslipi-demia. Methods A randomized, double-blind placebo controlled and parallel group trial was conducted. Patients with CHD and CHD risk equivalents with mixed dyslipidemia were treated with 10 or 20 mg simvastatin for 6-12 weeks. Following with the treatment of patients whose low-density lipoprotein cholesterol (LDL-ch) reaching goal level (< 100 mg/dL) or close to the goal (< 130 mg/dL), while triglyceride (TG) ≥200 mg/dL and < 500 mg/dL, was combined with omega-3 fatty acids (3 g/d) or a placebo for 2 months. The effects of the treatment on HsCRP, total cholesterol (TC), LDL-ch, high-density lipoprotein cholesterol (HDL-ch), TG, lipoprotein (a) [LP (a)], apolipoprotein A1 (apoA1), apolipoprotein B (apoB), plasminogen activator inhibitor-1 (PAI-1), and tissue plasminogen activator (tPA) were investigated. Forty patients finished the study with each group consisting of twenty patients. Results (1) There were significant reductions of HsCRP, TG, TC, and TC/HDL-ch, which decreased by 2.16 ±2.77 mg/L (38.5%), 94.0 ±65.4 mg/dL (31.1%), 13.3 ±22.3 mg/dL (6.3%), 0.78 ±1.60 respectively in the omega-3 fatty acids group (P< 0.01, < 0.001, < 0.05, < 0.05) compared to the baseline. HsCRP and triglyceride reduction were more significant in omega-3 fatty acids group compared to the placebo group (P=0.021 and 0.011 respectively). (2) In the omega-3 fatty acids group, the values and percentage of TG reduction had a significantly positive relation with HsCRP reduction (r=0.51 and 0.45, P=0.021 and 0.047 respectively). Conclusion In CHD and CHD risk equivalent patients with mixed dyslipidemia, dyslipidemia’s therapeutic effect using simvastatin and omega-3 fatty acids may result from not only the combination of lipid adjustment, but also enhancement of their own nonlipid influences. 展开更多
关键词 simvastation omega-3 fatty acids mixed dyslipidemia high sensitive C-reactive protein
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CT MANIFESTATIONS IN PULMONARY ALVEOLAR PROTEINOSIS AND COMPARED WITH CHEST RADIOGRAPHY(REPORT OF SIX CASES)
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作者 俞肖一 严洪珍 +3 位作者 潘杰 张涛 刘维 杨宏 《Chinese Medical Sciences Journal》 CAS CSCD 1998年第4期238-241,共4页
The CT including HRCT appearances of six patients with histopathologically confirmed pulmonary alveolar proteinosis(PAP) were evaluated and compared with those of chest radiographs In all pati... The CT including HRCT appearances of six patients with histopathologically confirmed pulmonary alveolar proteinosis(PAP) were evaluated and compared with those of chest radiographs In all patients the CT manifestations were quite similar: bilateral and diffuse airspace consolidation was usually patchy or confluent with sharply defined margins, intermingled with normal lung tissue The configuration of lung lesions was “geographical” in outline with angulate, strait and curved margins There were white branching linear opacities within the ground glass background Although various pulmonary diseases may mimic PAP in some way, a full awareness of the characteristic CT appearances of PAP is helpful in achieving a correct diagnosis CT may provide more accurate evidence than chest radiograph for the evaluation of the extent and delineation of PAP 展开更多
关键词 pulmonary alveolar proteinosis CT
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Effects of Nitrogen Deposition on Tundra Vegetation Undergoing Invasion by Deyeuxia angustifolia in Changbai Mountains 被引量:6
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作者 JIN Yinghua XU Jiawei +4 位作者 WANG Yeqiao WANG Shaoxian CHEN Zhaoshuang HUANG Xiangtong NIU Lijun 《Chinese Geographical Science》 SCIE CSCD 2016年第1期99-108,共10页
In recent years, herbaceous species such as Deyeuxia angustifolia (Kom.) Y. L. Chang has invaded alpine tundra regions of the western slope of the Changbai Mountains. Because atmospheric nitrogen deposition is predi... In recent years, herbaceous species such as Deyeuxia angustifolia (Kom.) Y. L. Chang has invaded alpine tundra regions of the western slope of the Changbai Mountains. Because atmospheric nitrogen deposition is predicted to increase under a warming climate and D. angustifolia is sensitive to nitrogen addition, field experiments were conducted from 2010 to 2013 to determine the effect of increased nitrogen deposition on the mechanisms of D. angustifolia invasion. The goal of this study is to evaluate the impact of increased nitrogen deposition on the changes in alpine tundra vegetation (consisting mostly of Rhododendron chrysanthum Pall. and Vaccinium uliginosum Linn.). The results showed that: 1) simulated nitrogen deposition affected overall characteristics and structure of R. chrysanthum and E uliginosum communities and had a positive impact on the growth of tundra vegetation invaded by 1). angustifolia; 2) R. chrysanthum was more resistant to invasion by D. angustifolia than V.. uliginosum; 3) simulated nitrogen deposition could improve the growth and enhance the competitiveness of D. angustifolia, which was gradually replacing R. chrysanthum and V. uliginosum and might become the dominant species in the system in future, transforming alpine tundra into alpine meadow in the Chanebai Mountains. 展开更多
关键词 nitrogen deposition species invasion Deyeuxia angustifolia tundra vegetation Changbai Mountains
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A novel protein-DNA interaction involved with the CpG dinucleotide at -30 upstream is linked to the DNA methylation mediated transcription silencing of the MAGE-A1 gene 被引量:3
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作者 JieZHANG JianYU JunGU BaoMeiGAO YingJunZHAO PengWANG HongYuZHANG JingDeZHU 《Cell Research》 SCIE CAS CSCD 2004年第4期283-294,共12页
To understand the DNA-methylation mediated gene silencing mechanisms, we analyzed in cell culture of the promoter function of the MAGE-A1 gene, which is frequently demethylated and over-expressed in human hepatocellul... To understand the DNA-methylation mediated gene silencing mechanisms, we analyzed in cell culture of the promoter function of the MAGE-A1 gene, which is frequently demethylated and over-expressed in human hepatocellular carcinoma. We have established the correlation of the DNA methylation of the promoter CpG island with expression status of this gene in a panel of the established liver cancer cell lines. The crucial CpG dinucleotide(s) within the minimal promoter subjected to the control mediated by DNA methylation with profound biological functions was also delineated.Furthermore, a novel sequence-specific DNA-protein interaction at the -30 CpG dinucleotide upstream of the gene was found having a vital part to play in the DNA methylation mediated transcription silencing of the MAGE-A1 gene. Our results would not only provide new insights into the DNA methylation mediated mechanisms over transcription of the MAGE-A1 gene, but also pave the way for further defining the cross-talk among DNA methylation, histone modification and chromatin remodeling in detail. 展开更多
关键词 MAGE-A1 DNA methylation transcriptional regulation.
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Stratigraphy of Upper Cretaceous──Paleogene deposits of northwestern Zeya──Burya sedimentary basin 被引量:1
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作者 T.V. Kezina N.D. Litvinenko 《Global Geology》 2007年第2期130-147,共18页
In the northwestern Zeya──Bureya sedimentary basin, the authors studied coal deposits, including Ivanovsko-Erkovetskyu brown coal square on which is worked off largest Erkovetsky field of brown coal, extending to so... In the northwestern Zeya──Bureya sedimentary basin, the authors studied coal deposits, including Ivanovsko-Erkovetskyu brown coal square on which is worked off largest Erkovetsky field of brown coal, extending to south flank of the Mesozoic──Cenozoic Belogor'e depression. The verified stratigraphic scheme of the coalfield sedimentary sequence is substantiated by palynological data on core samples from 18 boreholes sampled in the course of detailed prospecting and by paleobotanical analysis of sections in the Yuzhnyi sector of the coalfield. Sections of the Erkovtsy, Arkhara Boguchan, and Raichikha brown-coal mines are correlated. Stratigraphic subdivisions distinguished in the studied sedimentary succession are the middle and upper Tsagayan subformations (the latter incorporating the Kivda Beds), Raichikha and Mukhino formations. 展开更多
关键词 Upper Cretaceous PALEOGENE Zeya-Burya sedimentary basin
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Structural Characteristics and Evolution of Jurassic Basins in the East of Middle Qilian Block 被引量:1
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作者 郑孟林 李明杰 +2 位作者 曹春潮 张勇军 徐世陆 《Journal of China University of Mining and Technology》 2003年第1期35-39,共5页
Structural characteristics of the Jurassic basins of Xining, Minhe, and Xiji in the east of middle Qilian were researched based on the data obtained by gravitational, magnetic, and seismic methods. The result shows th... Structural characteristics of the Jurassic basins of Xining, Minhe, and Xiji in the east of middle Qilian were researched based on the data obtained by gravitational, magnetic, and seismic methods. The result shows that each of these three basins is an independent structural unit with a NW strike and being separated by upheavals. Two groups of faults with NW and NE directions are developed in the basin, which controls the formation and evolution of the (Jurassic basins). The NW faults are the main ones while the NE faults are the secondary for controlling the sedimentation. Of the three basins, the Minhe basin is the favorable prospecting area. 展开更多
关键词 east of middle Qilian Jurassic basin structural characteristic EVOLUTION prospecting of oil and gas
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Characteristics of Quaternary deposits near Songjianghe Town on west slope of Changbai Mountain 被引量:1
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作者 WANGXi-kui LIJun-min ZHANGHong-yan 《Journal of Geoscientific Research in Northeast Asia》 2004年第2期143-148,共6页
On the basis of field survey, microscope sighting, TL dating and scanning electron microscope analysis, the characteristics of Quaternary deposits near Songjianghe Town on the west slope of Changbai Mountain are analy... On the basis of field survey, microscope sighting, TL dating and scanning electron microscope analysis, the characteristics of Quaternary deposits near Songjianghe Town on the west slope of Changbai Mountain are analyzed and described. There were two phases of volcanism during Mid-Late Quaternary. One occurred before 15.22×104 aB.P. and the other happened between 14.27×104 aB.P. and 1.41×104 aB.P. Volcanism is a landform-making process which makes the rough relief in the studied area become higher and higher. Flow water is a main erosion agency and it cuts into the basalts making river valleys. The Quaternary fluvial deposits distributed on terraces first come from the weathered debris of basement rocks, then they are transported and deposited by flow water. After 1.41×104 aB.P., the river water quickly cuts into the newly formed basalts making a deep valley. Volcanism in the studied area is a main landform-making event in Mid-Late Quaternary. 展开更多
关键词 VOLCANISM fluvial deposits Mid-Late Quaternary Songjiang River
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Function of the hemochromatosis protein HFE:Lessons from animal models 被引量:1
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作者 Kostas Pantopoulos 《World Journal of Gastroenterology》 SCIE CAS CSCD 2008年第45期6893-6901,共9页
Hereditary hemochromatosis (HH) is caused by chronic hyperabsorption of dietary iron. Progressive accumulation of excess iron within tissue parenchymal cells may lead to severe organ damage. The most prevalent type ... Hereditary hemochromatosis (HH) is caused by chronic hyperabsorption of dietary iron. Progressive accumulation of excess iron within tissue parenchymal cells may lead to severe organ damage. The most prevalent type of HH is linked to mutations in the HFE gene, encoding an atypical major histocompatibility complex class I molecule. Shortly after its discovery in 1996, the hemochromatosis protein HFE was shown to physically interact with transferrin receptor 1 (TfR1) and impair the uptake of transferrin-bound iron in cells. However, these findings provided no clue why HFE mutations associate with systemic iron overload. It was later established that all forms of HH result from misregulation of hepcidin expression. This liverderived circulating peptide hormone controls iron efflux from duodenal enterocytes and reticuloendothelial macrophages by promoting the degradation of the iron exporter ferroportin. Recent studies with animal models of HH uncover a crucial role of HFE as a hepatocyte iron sensor and upstream regulator of hepcidin. Thus, hepatocyte HFE is indispensable for signaling to hepcidin, presumably as a constituent of a larger ironsensing complex. A working model postulates that the signaling activity of HFE is silenced when the protein is bound to TfR1. An increase in the iron saturation of plasma transferrin leads to displacement of TfR1 from HFE and assembly of the putative iron-sensing complex. In this way, iron uptake by the hepatocyte is translated into upregulation of hepcidin, reinforcing the concept that the liver is the major regulatory site for systemic iron homeostasis, and not merely an iron storage depot. 展开更多
关键词 HEPCIDIN Iron metabolism TRANSFERRIN HEMOJUVELIN Bone morphogenetic proteins
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Organic matter enrichment in the first member of the Xiagou formation of the lower Cretaceous in the Jiuquan Basin, China 被引量:2
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作者 Lixin Pei Gang Gao +4 位作者 Wenzhe Gang Zhilong Huang Guofu Ma Zhiming Yang Jianjun Chen 《Acta Geochimica》 EI CAS CSCD 2016年第1期95-103,共9页
The sources and enrichment of organic matter in a sediment core in the first member of the Xiagou Formation(K_1g^1) from the Chang 2-2 borehole of the Jiuquan Basin,NW China,have been examined using Rock-Eval,maceral,... The sources and enrichment of organic matter in a sediment core in the first member of the Xiagou Formation(K_1g^1) from the Chang 2-2 borehole of the Jiuquan Basin,NW China,have been examined using Rock-Eval,maceral,carbon isotopes and biomarker data.This data indicates that highly variable organic matter sources and preservation conditions in response to climate change.TOC content,HI,and δ^(13)C value were strongly correlated with the abundance of gammacerane,woody organic matter content,steranes/hopanes ratio,and C_(29) sterane content.This correlation demonstrates the importance that the control of the salinity of the depositional environment and organic matter sources can have upon the enrichment,type,and carbon isotopic composition of organic matter.In the Jiuquan Basin's relatively high temperature and arid climate,high salinity lakes with high primary productivity of algae,planktons,and bacteria,and good organic matter preservation conditions(anoxic bottom water) resulted in the enrichment of isotopically-light algae-bacterial organic matter.In the Jiuquan Basin's regions with a relatively low temperature and wet climate,fresh lakes with low primary productivity of algae,planktons,and bacteria received significant terrigenous high plants input,resulting in the deposition of a low abundance of isotopically heavier terrestrial organic matter. 展开更多
关键词 Enrichment Organic matter Lacustrine Lower Cretaceous Jiuquan Basin
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The Contribution of Opal-Associated Phosphorus to Bioavailable Phosphorus in Surface and Core Sediments in the East China Sea 被引量:2
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作者 LI Huanxin HE Huijun +4 位作者 YANG Shifeng LIU Yanli CHE Hong LI Mujian ZHANG Jing 《Journal of Ocean University of China》 SCIE CAS CSCD 2018年第3期571-580,共10页
To improve the burial flux calculations of bioavailable phosphorus (P) and study opal-associated P (Opal-P) in the East China Sea (ECS), surface and core sediments were collected in the Changjiang Estuary (CE)... To improve the burial flux calculations of bioavailable phosphorus (P) and study opal-associated P (Opal-P) in the East China Sea (ECS), surface and core sediments were collected in the Changjiang Estuary (CE) and the south of the Cheju Island. In this study, sedimentary P was operationally divided into seven different forms using modified sedimentary extraction (SEDEX) technique: LSor-P (exchangeable or loosely sorbed P), Fe-P (easily reducible or reactive ferric Fe-bound P), CFA-P (authigenic carbonate fluorapatite and biogenic apatite and CaCO3-bound P), Detr-P (detrital apatite), Org-P (organic P), Opal-P and Ref-P (refractory P). The data revealed that the concentrations of the seven different P forms rank as Detr-P 〉 CFA-P 〉 Org-P 〉 Ref-P 〉 Opal-P 〉 Fe-P 〉 LSor-P in surface sediments and CFA-P 〉 Detr-P 〉 Org-P 〉 Ref-P 〉 Fe-P 〉 Opal-P 〉 LSor-P in core sediments. The distributions of the total phosphorus (TP), TIP, CFA-P, Detr-P are similar and decrease from the CE to the south of the Cheju Island. Meanwhile, Org-P and Opal-P exhibit different distribution trends; this may be affected by the grain size and TOM. The concentrations of potentially bioavailable P are 9.6-13.0 μmol g^-1 and 10.0-13.6 μmol g^-1, representing 61%-70% and 41%?64% of the TP in surface and core sediments, respectively. The concentrations of Opal-P are 0.6-2.3 μmol g^-1 and 0.6-1.4 μmol g^-1 in surface and core sediments, ac-counting for 5.3%?19.8% and 4.2%?10.6% of bioavailable P, respectively. The total burial fluxes of Opal-P and bioavailable P are 1.4×10^9 mol y^-1 and 1.1×10^10 mol yr^-1 in the ECS, respectively. Opal-P represents about 12.7% of potentially bioavailable P, which should be recognized when studying P cycling in marine ecosystems. 展开更多
关键词 phosphorus speciation opal-associated P burial flux SEDIMENTS East China Sea
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Petrography,geochemistry and provenance of the sediments of the Early Cretaceous Yanguoxia Formation,Lanzhou-Minhe Basin,Northwest China 被引量:1
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作者 DU Ding-ding MUGHAL Muhammad Saleem ZHANG Cheng-jun 《Journal of Mountain Science》 SCIE CSCD 2018年第9期2068-2088,共21页
Lanzhou-Minhe Basin is situated on the middle Qilian orogenic belt. Yanguoxia Formation contains abundance of maroon siltstones, mudstones and red sandstones of the lake facies. These sedimentary rocks recorded the pr... Lanzhou-Minhe Basin is situated on the middle Qilian orogenic belt. Yanguoxia Formation contains abundance of maroon siltstones, mudstones and red sandstones of the lake facies. These sedimentary rocks recorded the process of the tectonic uplift of Qilian Mountains during the Early Cretaceous. We discovered plentiful dinosaur footprints, worm burrows, bird footprints, worm tracks-trails, ripple marks and cross lamination in the Yanguoxia site. Integrated petrographic studies classified sandstones of Yanguoxia Formation as feldspathic litharenite. All plots in the QFL(Q or Qt, total quartz; F, feldspar; L, lithic grains) and Qm FLt(Qm, monocrystalline quartz; Lt, lithic grains plus polycrystalline quartz) diagrams fall in the recycled orogen provenance field and quartzose recycled field, respectively, implying the source occurred the tectonic activity. Furthermore, geochemical study indicates that the Yanguoxia standstone was formed in an unstable continental setting due to the northwards movement of Indian Plate triggered the collision between the Qilian fold belt and the Qinlingfold belt. These sediments were derived from a mixed source and then deposited in the Lanzhou-Minhe Basin. Most of the felsic components were derived from the granitoid rocks of the Qilian Mountains due to the rapid and intense uplift during the Early Cretaceous while the mafic components were contributed by the basic and ultrabasic rocks of the rapidly rising ophiolite in the Qilian Mountain area. Bivariant log-log plot of Qp/(F+L)(Qp, polycrystalline quartz) against Q/(F+L) shows that Yanguoxia Formation was deposited in the semihumid and semi-arid. Moreover, the pollen also exhibits that the environmental condition during the deposition of Yanguoxia Formation was warm and wet, which affirm such environment was benefit to dinosaur survival. Geochemical study also infers that the Yanguoxia Formation was deposited under the oxidizing condition in a shallow marine environment. The minerals identified from the X-ray diffraction(XRD) analysis of shale and siltstone samples are 4.74%-33.53% clays, 23.45%-41.70% carbonates and 33.99%-71.81% quartz, respectively, which infer that depositional conditions remained uniform during the formation of shales or siltstones of Yanguoxia Formation. 展开更多
关键词 Lanzhou-Minhe Basin YanguoxiaFormation PETROGRAPHY GEOCHEMISTRY Provenanceand weathering Teetonism and environment
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Comparative studies on the biochemical characteristics of natural actomyosin isolated from PSE and normal pork 被引量:2
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作者 丁玉庭 桑卫国 陈艳 《Journal of Zhejiang University Science》 EI CSCD 2004年第6期684-688,共5页
Biochemical changes of natural actomyosin from fresh pale, soft, exudative (PSE) and normal pork were studied,and the effects of different storage temperatures and different incubation temperature and times on sample ... Biochemical changes of natural actomyosin from fresh pale, soft, exudative (PSE) and normal pork were studied,and the effects of different storage temperatures and different incubation temperature and times on sample superprecipitation,total sulfhydryl (-SH) content, and ATP (adenosine triphosphate) sensitivity were investigated. The results demonstrated that ATPase activity and thermal stability of PSE actomyosin were lower than those of normal pork; and that PSE actomyosin had higher -SH content than that of normal pork at all incubation temperatures and times tested. 展开更多
关键词 PSE PORK ACTOMYOSIN Biochemical characteristics
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Trans-acting factors from the human fetal liver bindingto the human ε-globin gene silencer 被引量:2
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作者 YANZHIJIANG CHUJIANG 《Cell Research》 SCIE CAS CSCD 1997年第2期151-159,共9页
The developmental stage-specific silencing of the human ε-globin gene during embryonic life is controlled, inpart, by the silencer (-392bp~-177bp) upstream of thisgene. In order to elucidate its role, the nuclear ex... The developmental stage-specific silencing of the human ε-globin gene during embryonic life is controlled, inpart, by the silencer (-392bp~-177bp) upstream of thisgene. In order to elucidate its role, the nuclear extractfrom the human fetal liver has been prepared and the interactions between trans-acting factors and this silencerelement have been examined. By using DNasel footprinting assay, a major protected region from -278bp to -235bpwithin this silencer element was identified. Furthermore,we found in gel mobility shift assay and Southwestern blotting assay that there were at least four trans-acting factors (MW ≈ 32, 28, 26 and 22kD) in the nuclear extractisolated from the human fetal liver, which could specifically bind to this region. Our results suggested that thesetrans-acting factors might play an important role in silencing the human embryonic ε-globin gene expression at thefetal stage through the interactions with this silencer. 展开更多
关键词 Human ε-globin gene SILENCER transacting factor
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Sedimentological features of Cretaceous--Tertiary (K/T) boundary section along Heilongjiang River,Northeast China 被引量:1
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作者 Shigeyuki Suzuki Hakuyu Okada +1 位作者 SUN Chunlin SUN Ge 《Global Geology》 2010年第1期20-27,共8页
The Jiayin area along the Heilongjiang River in Northeast China has attracted stratigraphic and sedimentological interests recently because the Cretaceous--Tertiary (K/T) boundary should be located in this non-marine ... The Jiayin area along the Heilongjiang River in Northeast China has attracted stratigraphic and sedimentological interests recently because the Cretaceous--Tertiary (K/T) boundary should be located in this non-marine succession.Dinosaur remains disappear suddenly at the upper part of the Maastrichtian,whereas plants gradually evolved throughout the succession.Analysis of sedimentary facies has been carried out and paleo-environments through Upper Cretaceous to lower Paleocene sections are reconstructed.Fluvial to lacustrine sedimentary environments are inferred from the facies.Several debris flow events have been identified,and it is in these deposits that the dinosaur fossils are concentrated. 展开更多
关键词 sedimentary environment sedimentary facies Heilongjiang River area K/T boundary
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