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Adsorption,in vitro digestion and human gut microbiota regulation characteristics of three Poria cocos polysaccharides 被引量:2
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作者 Fangming Zhang Hui Zheng +10 位作者 Tao Zheng Pan Xu Yao Xu Yuxin Cao Fan Jia Yiqiong Zeng Yubing Fan Kai He Xinwen Dai Fengfei Hou Yong Yang 《Food Science and Human Wellness》 SCIE CSCD 2024年第3期1685-1697,共13页
Poria cocos(PC)is a famous traditional Chinese medicine(TCM)and a widely used healthcare ingredient,which has antiobesity,enhancing immunity and improving sleep effects.Traditionally,only water-soluble poria polysacch... Poria cocos(PC)is a famous traditional Chinese medicine(TCM)and a widely used healthcare ingredient,which has antiobesity,enhancing immunity and improving sleep effects.Traditionally,only water-soluble poria polysaccharide(WSP)is extracted and applied for clinical application,while insoluble polysaccharide(alkali-soluble poria polysaccharide,ASP)is discarded as herb residue.However,the whole PC has also been historically utilized as functional herbal food.Considering the beneficial role of dietary fiber and the traditional use of PC,ASP may also contribute substantially to the therapy function of PC.Compared to WSP,little attention has been paid to ASP and ASP modified product carboxymethyl poria polysaccharide(CMP)which has been used as an antitumor adjuvant drug.In this study,the oil,cholesterol,metal ions and polyphenols adsorption ability,in vitro simulated digestive and the gut microbiota fermentation characteristics of WSP,ASP and CMP were studied to evaluate the functional values of three P.cocos polysaccharides(PCPs).The results showed that all three PCPs had good adsorption capacity on cholesterol,polyphenols and metal ions(Cd^(2+)/Zn^(2+)/Mg^(2+)),among which ASP showed the highest capacity than WSP and CMP.The adsorption capacity of all three PCPs on heavy metal ions(Cd^(2+)/Zn^(2+))was stronger than that of non-heavy metal ions(Mg^(2+));The in vitro digestibility of all three PCPs was very low,but WSP was slightly higher than ASP and CMP;Moreover,the indigestible residue of all three PCPs could improve the richness and diversity of gut microbiota,among which ASP had the greatest influence.In general,ASP and CMP could significantly promote the proliferation of some probiotics and inhibit the growth of some harmful bacteria.The gut microbiota diversity of CMP was reduced,but the richness of probiotics,especially Parabacteroides distasonis was significantly enhanced compared with the ASP group,and the growth of harmful bacteria Klebsiella pneumoniae was inhibited after CMP treatment.The short-chain fatty acids(SCFAs)analysis results showed that all three PCPs could significantly promote the production of acetic acid,propionic acid and the total acid content compared with blank control group,and SCFAs producing activity was positively correlated with the proliferative capacity of probiotics.Taken together,the good adsorption characteristics and gut microbiota regulatory activity of ASP may lay foundation for its lipid-lowering and immune-improving function.Additionally,the probiotic effect of CMP and ASP indicated that except for only use the water extract of PC in clinic,CMP and ASP also can be used in healthcare to take full advantage of this valuable medicine. 展开更多
关键词 Poria cocos polysaccharides Alkali-soluble poria polysaccharide Carboxymethyl poria polysaccharide Adsorption characteristics In vitro simulated digestion In vitro simulated gut microbiota fermentation
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Effects of Poria cocos polysaccharide on growth performance,physiological parameters,and lipid metabolism of spotted sea bass Lateolabrax maculatus
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作者 Jing LU Zhangfan HUANG +2 位作者 Youling YE Anle XU Zhongbao LI 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2024年第1期316-331,共16页
The aquaculture industry has developed significantly over the past few decades and has had a substantial impact on the global food supply and marine fisheries resources.However,some problems arise behind the scenes du... The aquaculture industry has developed significantly over the past few decades and has had a substantial impact on the global food supply and marine fisheries resources.However,some problems arise behind the scenes due to excessive intensive farming,such as slow animal growth,frequent disease,and lipid metabolism disorders.These problems have limited the sustainable development of the aquaculture industry,and a continuable solution is required.The use of fungal polysaccharide appears to provide a solution to these problems.Therefore,different supplemented levels of Poria cocos polysaccharide(PCP)(0,0.4,0.8,1.2,1.6,and 2.0 g/kg,respectively)were fed to spotted sea bass(Lateolabrax maculatus)in similar size(30.28±0.18 g)in current study.The effects of PCP on growth,physiological parameters,and lipid metabolism of spotted sea bass were investigated after a 4-week rearing period.Results showed,fish with PCP intake presented a significantly higher weight gain,specific growth rate,and a significantly lower feed conversion ratio.Significantly higher trypsin activity in liver and intestine were observed in fish with PCP intake.The superoxide dismutase activity in serum and liver of fish with PCP intake were significantly improved,while significantly higher serum total antioxidant capacity and hepatic catalase activity were also observed.However,no significant differences in lysozyme and alkaline phosphatase activity were evident among groups.Fish with PCP intake showed a significantly lower total cholesterol,but no noteworthy change in triglyceride and lipid-metabolismrelated genes expression were observed among groups.Results indicated that intake of PCP has a positive effect on growth and antioxidant capacity of spotted sea bass,but seems to have a limited effect on the non-specific immunity and lipid metabolism of spotted sea bass.Based on the regression analysis results,1.4 g/kg of PCP is the optimal dose for spotted sea bass in size(30.28±0.18 g). 展开更多
关键词 spotted sea bass Poria cocos POLYSACCHARIde GROWTH lipid metabolism
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COMPARISON OF POLYSACCHARIDES ISOLATED FROM THE MYCELIA OF A CULTIVATED STRAIN OF PORIA COCOS GROWN IN DIFFERENT LIQUID CULTURE MEDIA 被引量:7
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作者 Peter Chi Keung Cheung 张俐娜 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2003年第4期465-472,共8页
Mycelium of a cultivated strain of Poria cocos was grown by submerged fermentation in a liquid mediumcontaining corn steep liquor with orbital shaking. Six polysaccharides coded as ac-PCM1, ac-PCM2, ac-PCM3-Ⅰ andⅡ, ... Mycelium of a cultivated strain of Poria cocos was grown by submerged fermentation in a liquid mediumcontaining corn steep liquor with orbital shaking. Six polysaccharides coded as ac-PCM1, ac-PCM2, ac-PCM3-Ⅰ andⅡ, ac-PCM4-Ⅰand Ⅱ were isolated from the myelium by extracting with 0.9% NaCl aqueous solution, hot water, 0.5 mol/L NaOHaqueous solution and 88% formic acid. Exo-polysaccharide was obtained from the culture medium and coded as ac-PCM0.The monosaccharide composition and molecular weights of these polysaccharides were characterized by using infraredspectroscopy, gas chromaography, elemental analysis, ^(13)C-NMR, viscometry and light scattering. The results indicated thatac-PCM0, ac-PCM1 and ac-PCM2 are heteropolysaccharides containing glucose, galactose, mannose and fucose, and ac-PCM3-Ⅰ and ac-PCM3-Ⅱ mainly consist of D-glucose. The content of the glucose in the polysaccharides increased with theisolation progress. Remarkably, α-glucan and β-glucan coexisted in the extract by NaOH aqueous solution (ac-PCM3), andcould be separated by chemical methods. The protein in the ac-PCM polysaccharides cultured from the medium containingcorn steep liquor was higher than that in the ab-PCM from the medium with bran extract. Therefore, the polysaccharidesfrom Poria cocos mycelia cultured in different media have different chemical composition, molecular weights and conformations. 展开更多
关键词 Poria cocos mycelium Culture medium POLYSACCHARIde Monosaccharide composition Molecular weight
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PREPARATION AND STRUCTURE OF FIVE DERIVATIVES OF β-(1→3)-D-GLUCAN ISOLATED FROM PORIA COCOS SCLEROTIUM 被引量:7
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作者 张俐娜 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2004年第2期137-145,共9页
A new solvent of cellulose (1.5 mol/L NaOH/0.5 mol/L urea aqueous solution) was used as one of the homogeneous reaction media of polysaccharides for methylation, hydroxyethylation and hydroxypropylation. A water insol... A new solvent of cellulose (1.5 mol/L NaOH/0.5 mol/L urea aqueous solution) was used as one of the homogeneous reaction media of polysaccharides for methylation, hydroxyethylation and hydroxypropylation. A water insoluble β -(1—>3)-D-glucan, sample PCS3- isolated from fresh sclerotium of Poria cocos was sulfated in dimethyl sulfoxide (Me 2 SO), carboxymethylated in NaOH, isopropanol solution, as well as methylated, hydroxyethylated and hydroxypropylated in the new solvent system, respectively, to obtain five water-soluble derivatives coded as S-PCS3- C- PCS3- M-PCS3- HE-PCS3- and HP-PCS3- Their chemical structure and distribution of substitution were characterized by infrared spectroscopy (IR), elementary analysis (EA), 1 H-NMR, 13 C-NMR, 2D-COSY, 2D-TOCSY and 2D- 1 H-detected 1H 13C HMQC spectra. The results reveal that the relative reactivity of hydroxyl groups of the β -(1-?3)-D-glucan is in the order C-6 > C-4 > C-2 on the whole. The substitution of the samples S-PCS3- C-PCS3- and M-PCS3- occurred mainly at C-6 position and secondly at C-4 and C-2 positions, and that of HE-PCS3- occurred at C-6 and C-4 positions and of HP-PCS3- almost completely occurred at C-6 position. The degrees of substitution (DS) obtained from 13 C-NMR range from 0.23 to 1.27. The water solubility of the derivatives is in the order S-PCS3- >C-PCS3- >M-PCS3- >HE-PCS3- >HP-PCS3- This work provides a novel and nonpolluting process for the methylation, hydroxyethylation and hydroxypropylation of β -(1—>3)-D-glucan. 展开更多
关键词 Chemical structure SULFATION CARBOXYMETHYLATION METHYLATION Hydroxyethylation HYDROXYPROPYLATION β-D- glucan Poria cocos sclerotium NMR
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Effects of Crude Extract of Poria cocos on the Tension of Jejunum and Cecum in Rabbits in vitro 被引量:3
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作者 Jun WANG Yongshuai PENG +1 位作者 Fengsun WU Jun HUO 《Agricultural Biotechnology》 CAS 2015年第5期54-55,60,共3页
[ Objective] This study aimed to investigate the effects of crude extract of Poria cocos on intestinal smooth muscle contraction of rabbits in vitro and re- veal the related mechanism. [Method] With in vitro experimen... [ Objective] This study aimed to investigate the effects of crude extract of Poria cocos on intestinal smooth muscle contraction of rabbits in vitro and re- veal the related mechanism. [Method] With in vitro experimental method, using the tension of jejunal and cecal smooth muscle as an indicator, 3.75, 7.50, 15.00, and 22.5 g/L crude extract of P. cocos were added into Tyrede's solution of jejunum and cecum tissues of rabbits to observe the effects of crude extract of P. cocos on motion dynamics of jejunum and cecum of rabbits. [ Result] The addition of crude extract of P. cocos could inhibit the contraction of jejunal and cecal smooth muscle of rabbits in vitro, enhance contraction tension and relaxation tension, and reduce contraction amplitude. The effects were improved as the dose of crude extract of P. cocos increased, displaying a dose-effect relationship. [Condusion] This study provided theoretical basis for the clinical use of P. cocos. 展开更多
关键词 Poria cocos RABBITS JEJUNUM CECUM CONTRACTION
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Carbon dots derived from Poria cocos polysaccharide as an effective“on-off”fluorescence sensor for chromium(Ⅵ)detection 被引量:3
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作者 Qianqian Huang Qianqian Bao +4 位作者 Chengyuan Wu Mengru Hu Yunna Chen Lei Wang Weidong Chen 《Journal of Pharmaceutical Analysis》 SCIE CAS CSCD 2022年第1期104-112,共9页
Chromium is a harmful contaminant showing mutagenicity and carcinogenicity.Therefore,detection of chromium requires the development of low-cost and high-sensitivity sensors.Herein,blue-fluorescent carbon quantum dots ... Chromium is a harmful contaminant showing mutagenicity and carcinogenicity.Therefore,detection of chromium requires the development of low-cost and high-sensitivity sensors.Herein,blue-fluorescent carbon quantum dots were synthesized by one-step hydrothermal method from alkali-soluble Poria cocos polysaccharide,which is green source,cheap and easy to obtain,and has no pharmacological activity due to low water solubility.These carbon quantum dots exhibit good fluorescence stability,water solubility,anti-interference and low cytotoxicity,and can be specifically combined with the detection of Cr(Ⅵ)to form a non-fluorescent complex that causes fluorescence quenching,so they can be used as a label-free nanosensor.High-sensitivity detection of Cr(Ⅵ)was achieved through internal filtering and static quenching effects.The fluorescence quenching degree of carbon dots fluorescent probe showed a good linear relationship with Cr(Ⅵ)concentration in the range of 1-100μM.The linear equation was F;/F=0.9942+0.01472[Cr(Ⅵ)](R;=0.9922),and the detection limit can be as low as 0.25μM(S/N=3),which has been successfully applied to Cr(Ⅵ)detection in actual water samples herein. 展开更多
关键词 Carbon dots Alkali-soluble Poria cocos polysaccharide Cr(Ⅵ)detection Internal filtering effect Static quenching effect
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The Status Quo and Countermeasures of Planting and Industrial Development of Poria cocos in Luotian County
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作者 CHENG Huan-zhong CHENG Shui-ming 《Asian Agricultural Research》 2012年第6期29-32,37,共5页
We conduct a field survey of the status quo of planting and industrial development of Poria cocos in Luotian County.The results show that at present,Luotian County develops a set of standardized Poria cocos cultivatio... We conduct a field survey of the status quo of planting and industrial development of Poria cocos in Luotian County.The results show that at present,Luotian County develops a set of standardized Poria cocos cultivation technique,and some areas use the guideline of "four changes" to plants Poria cocos.The main problems faced by planting of Poria cocos currently are as follows:insufficient popularization of standardized Poria cocos cultivation technique;low processing level of Poria cocos;chaotic source of germplasm;lack of science and technology input;single industrial development pattern;shortage of well-known brands of products.In accordance with the above findings,we put forward the following recommendations:extensively promoting the guideline of " four changes";focusing on development and utilization of Poria cocos byproducts;implement listing-for-sales to clarify the source of Poria cocos strain;tightening the bonds with research institutes and large enterprises to promote science and technology input into Poria cocos;encouraging the coexistence of diverse industrial development pattern. 展开更多
关键词 Poria cocos Planting Luotian County INDUSTRIALIZATION COUNTERMEASURES
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Diagnosis of Boron Deficiency in Green Dwarf Coconut Palm 被引量:1
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作者 Leandro Glaydson da Rocha Pinho Pedro Henrique Monnerat +2 位作者 Andre Assis Pires Marta Simone Mendonca Freitas Claudio Roberto Marciano 《Agricultural Sciences》 2015年第1期164-174,共11页
The diagnosis of boron deficiency in coconut palms has been hampered by lack of information about its distribution in the plant. Two experiments were conducted, one in a greenhouse to induce boron deficiency in dwarf ... The diagnosis of boron deficiency in coconut palms has been hampered by lack of information about its distribution in the plant. Two experiments were conducted, one in a greenhouse to induce boron deficiency in dwarf green coconut palms, and other in the field, in which the plants received doses of boric acid, B(OH)3. The objective was to verify symptoms of boron deficiency and boron content variation in canopy, leaves and folioles (or leaflets). Boron deficient plants led leaves and folioles to become deformed. The deficient and sufficient contents of boron varied significantly in the canopy, but did not vary in leaves. The boron content increased significantly from bottom to the apex of the folioles in both treatments. To survey the level of boron in the coconut palm, the ideal is, using samples taken from the youngest leaf, to calculate the relation between the boron content in the apex of the foliole and the content in the center or in the folioles bottom, with minimum values 2.2 or 2.7, respectively. 展开更多
关键词 SYMPTOMS Leaf Analysis deficiency Induction Boric Acid SAMPLES cocos nucifera
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Synergistic Mixture of Cyperus esculentus, Phoenix dactylifera and Cocos nucifera Aqueous Extract: Its Liver and Kidney Benefits in Male Albino Rat Model
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作者 Tamuno-Boma Odinga Cletus Barizoge Lemii +4 位作者 Iyaeneomi Ransome Daka Christine U. Gabriel-Brisibe Sarah K. Enebeli Iyingiala Austin-Asomeji Felicia Ucheawaji Edward 《Journal of Biosciences and Medicines》 2023年第10期63-75,共13页
Background: The synergistic mixture of Cyperus esculentus, Phoenix dactylifera and Cocos nucifera (STCD) aqueous extract is a common drink in Port Harcourt, Nigeria. It is assumed to have various health benefits. Howe... Background: The synergistic mixture of Cyperus esculentus, Phoenix dactylifera and Cocos nucifera (STCD) aqueous extract is a common drink in Port Harcourt, Nigeria. It is assumed to have various health benefits. However, the synergistic mixture of the content has not been studied scientifically, hence the need to evaluate its effect on the liver and kidney being part of the body’s metabolic organs. Aim: This study evaluated the synergistic mixture of Cyperus esculentus, Phoenix dactylifera and Cocos nucifera (STCD) aqueous extract in male albino rats. Methods: Acute toxicity LD<sub>50</sub> of STCD was carried out, afterwards, fifteen male albino rats were grouped into three groups with 5 rats in each group;Control, 200 mg/kg, 400 mg/kg STCD. The rats were administered STCD orally 24 hourly, for 21 days, with feed and water ad libitum. At the end of the experiment, blood samples were collected for biochemical analysis of the liver and kidney biomarkers, while the liver and kidney tissues were harvested for histopathological examination using standard laboratory methods. Descriptive statistics were computed and expressed as Mean ± SD. One-way ANOVA and Turkeys test was performed. P value ≤0.05 was considered statistically significant. Results: Acute toxicity LD50 of STCD was observed to be ≥2404.2 mg/kg body weight. An increase in the percentage body weight difference of 8.39% and 2.86% was observed for 200 and 400 mg/kg STCD groups. Also, the liver weight was observed to increase in 400 mg/kg (3.92 ± 1.42) in comparison to the control group (3.48 ± 1.61), a decrease in the kidney weight was observed in all groups administered STCD in comparison to the control group. Administration of STCD at both 200 and 400 mg/kg revealed a decrease in the concentration of the hepatic biomarkers AST, ALT, ALP, TP, Albumin, Total and conjugated bilirubin. The kidney biomarker Urea was observed to decrease in concentration for 200 mg/kg STCD (4.60 ± 1.83) and 400 mg/kg STCD (4.76 ± 0.74) when compared to the control group (6.32 ± 2.74). A decrease in Creatinine was observed in 200 mg/kg (91.80 ± 34.69) and 400 mg/kg (98.60 ± 15.53) in comparison to the control group (117.60 ± 42.88). The histological examination of the liver of rats administered STCD revealed structural normal central vein, hepatocytes and portal tract. The kidney examination revealed normal glomeruli and normal tubule. Conclusion: The findings of this study opine that STCD improved the health of both the liver and kidney as evidenced via the biomarkers and histological examinations of the liver and kidney. This study therefore recommends the intake of STCD at moderate doses for improved liver and kidney function due to its bioactive compounds and nutritional content. 展开更多
关键词 Cyperus esculentus (Tiger nuts) Phoenix dactylifera (Dates) and cocos nucifera (coconuts) LIVER KIDNEY Male Rats
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Pachyman Derivatives from Poria Cocos : A Potential Biocompatible and Biodegradable Excipients for Drug Delivery System
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作者 Yu-Lin XIAO Shu-Cai LIANG Guo-Fu QIU Xian-Ming HU~Δ(College of Pharmacy, Wuhan University, Wuhan 430072, China) 《生物医学工程学杂志》 EI CAS CSCD 北大核心 2005年第S1期123-124,共2页
关键词 A Potential Biocompatible and Biodegradable Excipients for Drug delivery System Pachyman derivatives from Poria cocos
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Influence of Solvent onto Chemical Extraction of America-Type Coconut (Coco nucifera L.) Fbers: Analysis of Physicochemical, Mechanical and Morphological Properties
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作者 Delphine Korgai Gandai Zara Haman +4 位作者 Djoda Pagore Frederic Memtine Ndong Augustin Abdourhamane Nsangou Niraka Blaise Hambate Gomdje Valery 《Journal of Textile Science and Technology》 2024年第3期64-81,共18页
In this study, the natural fibers from Coconuts of the species Coco nucifera L. were Chemically extracted in different solvents such as sodium hydroxide (SH), acetone (AC) and sodium hydroxide-acetone (SHA) for their ... In this study, the natural fibers from Coconuts of the species Coco nucifera L. were Chemically extracted in different solvents such as sodium hydroxide (SH), acetone (AC) and sodium hydroxide-acetone (SHA) for their applications in the textile industries. Structural, morphological and physico-mechanical characterizations such as X-ray diffraction (XRD), Fourier transform infrared spectrometry (FTIR), scanned electron microscopy (SEM), measurements of density, Young’s modulus, water absorption rate and humidity were evaluated. The XRD and FTIR results show that Coco nucifera L. fibers contains type I cellulose. Mechanical characterizations were also carried out. These results show that by varying the different solvents used, the physico-chemical, mechanical and morphological properties of the fibers change, which implies that the solvent has an influence on the properties of these fibers. The fibers extracted by the sodium hydroxide-acetone mixture have a linear density of 1.636, the percentage of water absorption is 62.428%, the percentage of moisture absorption 9.605% compared to other values in the literature shows that this solvent mixture improves the properties of coconut fibers which contain type I cellulose. The tensile stress is 0.013 GPa, the percentage strain is 49.836% and the Young’s modulus is 0.114 GPa as well as the percentage elongation show that these fibers are elasto-plastic. The values obtained mean that these fibers are suitable for use in textiles. 展开更多
关键词 Chemical Extraction Cellulose coco nucifera L. Fibers ELASTO-PLASTIC Textiles
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茯苓菊苣复合多糖对二型糖尿病大鼠血糖水平的影响
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作者 王晓宇 邢书燕 +2 位作者 张丹洋 李亚晨 包永明 《西北农林科技大学学报(自然科学版)》 北大核心 2025年第1期133-143,共11页
【目的】探究茯苓菊苣复合多糖(Poria cocos and chicory complex polysaccharides,PCCP)对二型糖尿病(T2DM)模型大鼠的降血糖及肝脏保护作用,为天然多糖产品的开发应用提供参考。【方法】制备茯苓菊苣复合多糖,测定其中的多糖含量。随... 【目的】探究茯苓菊苣复合多糖(Poria cocos and chicory complex polysaccharides,PCCP)对二型糖尿病(T2DM)模型大鼠的降血糖及肝脏保护作用,为天然多糖产品的开发应用提供参考。【方法】制备茯苓菊苣复合多糖,测定其中的多糖含量。随机挑选10只SD大鼠作为正常对照组(CK1),其余大鼠利用高脂饮食诱导联合腹腔注射低剂量链脲佐菌素(streptozotocin,STZ)建立二型糖尿病大鼠模型。将糖尿病模型大鼠随机分为模型对照组(CK2)和茯苓菊苣复合多糖低、中、高剂量组(LM、MM、HM)及阳性对照(二甲双胍)组(CK3),每组10只,其中LM、MM、HM组分别每日灌胃茯苓菊苣复合多糖2.85,5.7,8.55 g/kg,CK3每日灌胃二甲双胍300 mg/kg,CK1和CK2每日灌胃等量生理盐水,连续灌胃4周。灌胃结束时检测大鼠体质量及餐后2 h血糖浓度、大鼠口服葡萄糖耐量(OGTT)和胰岛素耐量(ITT),以及血清中胰岛素浓度、血脂指标(总胆固醇(T-CHO)、总甘油三酯(TG)、低密度脂蛋白胆固醇(LDL-C)和高密度脂蛋白胆固醇(HDL-C)浓度)、肝损伤指标(肝脏系数和谷丙转氨酶(ALT)、谷草转氨酶(AST)活性),并测定肝脏组织的氧化应激指标(超氧化物歧化酶(SOD)、谷胱甘肽(GSH)、过氧化氢酶(CAT)活性)。显微镜下观察各组大鼠胰腺组织的病理变化。【结果】制备的茯苓菊苣复合多糖中多糖质量分数为(72.17±0.66)%。CK2大鼠组血糖与CK1组相比显著升高,MM组和HM组血糖与CK2组相比显著降低,体质量显著增加,肝脏系数显著降低。与CK2组相比,LM、MM、HM组大鼠胰岛素抵抗指数(HOMA-IR)显著降低,口服葡萄糖耐量和胰岛素耐量得到改善,AST和ALT活性显著降低;MM组T-CHO、TG、LDL-C浓度显著降低。显微观察结果表明,CK2组大鼠胰岛细胞数量明显减少,MM、HM组胰岛细胞数量有所恢复。肝组织氧化应激结果表明,CK2组大鼠SOD、CAT、GSH活性与CK1组相比显著降低,HM组SOD、CAT、GSH活性与CK2组相比显著升高。【结论】茯苓菊苣复合多糖具有降低二型糖尿病大鼠血糖的功效,对高血脂症有缓解作用,对肝脏和胰腺有保护作用。 展开更多
关键词 茯苓 菊苣 复合多糖 二型糖尿病 降血糖
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基于Copula双变量模拟的CoCo债券定价 被引量:5
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作者 李平 尹菁华 +1 位作者 来娜 黄光东 《系统工程学报》 CSCD 北大核心 2016年第6期772-782,共11页
用Copula函数刻画公司股价与核心一级资本比率(core tier 1 ratio,CTR)的相关性,然后通过模拟股价和CTR,建立了或有可转换债券(Co Co)以及带期权条款的或有可转换债券(Co Co Co)的定价模型.并将模型应用于塞浦路斯银行发行的CECS(conver... 用Copula函数刻画公司股价与核心一级资本比率(core tier 1 ratio,CTR)的相关性,然后通过模拟股价和CTR,建立了或有可转换债券(Co Co)以及带期权条款的或有可转换债券(Co Co Co)的定价模型.并将模型应用于塞浦路斯银行发行的CECS(convertible enhanced capital securities)债券,发现用Copula刻画股价与CTR相关性的定价结果与债券实际价格的差异优于假设两者独立时的结果.最后结合国际上已发行的Co Co和Co Co Co债券的相关条款以及我国银监会对于减记债的基本要求,以交通银行为例设计了中国版的Co Co债券和Co Co Co债券,并依据所给模型对它们进行了数值计算. 展开更多
关键词 coco债券 cocoCo债券 核心一级资本比率 Clayton COPULA
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考虑展期风险的可赎回CoCo债券定价 被引量:7
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作者 李平 李芳芳 +1 位作者 刘洁 黄光东 《管理科学学报》 CSSCI CSCD 北大核心 2019年第4期16-26,共11页
始于2007年的次贷危机结束之后,CoCo债券(contingent convertible bond)因为其能够在金融危机时迅速提高银行资本充足率而受到关注.本文考虑了展期风险对CoCo债券价格的影响,用Copula函数刻画股票价格与核心一级资本比率(Core Tier 1 Ra... 始于2007年的次贷危机结束之后,CoCo债券(contingent convertible bond)因为其能够在金融危机时迅速提高银行资本充足率而受到关注.本文考虑了展期风险对CoCo债券价格的影响,用Copula函数刻画股票价格与核心一级资本比率(Core Tier 1 Ratio,CTR)的相关性,用CIR模型刻画利率期限结构,并对CoCo债券的赎回进行判定,采用蒙特卡罗模拟法为带有可赎回条款的CoCo债券定价.将此模型应用于巴克莱银行发行的可赎回CoCo债券验证模型的有效性.最后,结合国际上已发行的CoCo债券的相关条款和我国银监会对于减记债(中国版CoCo债券)的基本要求,设计了中国版的CoCo债券,并在数值计算的基础上进行了股价冲击和银行业监管要求对CoCo债券价格影响的敏感性分析. 展开更多
关键词 可赎回coco债券 展期风险 COPULA CIR模型 跳扩散模型
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空穴注入层2T-NATA对OLED器件性能的影响 被引量:1
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作者 牟强 姚毅 +2 位作者 张方辉 靳宝安 蒋谦 《半导体技术》 CAS CSCD 北大核心 2010年第3期256-259,共4页
为了提高有机电致发光器件OLED的发光效率,引入2T-NATA作为空穴注入层,制备了结构为ITO/2T-NATA(Xnm)/NPB(25nm)/Alq3:C545T(20nm:质量分数4.5%)/Alq3(30nm)/LiF(1nm)/Al(100nm)的绿光器件,其中X为空穴注入层2T-NATA厚度。分析了2T-NAT... 为了提高有机电致发光器件OLED的发光效率,引入2T-NATA作为空穴注入层,制备了结构为ITO/2T-NATA(Xnm)/NPB(25nm)/Alq3:C545T(20nm:质量分数4.5%)/Alq3(30nm)/LiF(1nm)/Al(100nm)的绿光器件,其中X为空穴注入层2T-NATA厚度。分析了2T-NATA的蒸镀厚度分别0,5,10,15,20,25,30,35nm时器件的发光性能。结果表明,2T-NATA的HOMO能级较好的与ITO功函数匹配,降低了空穴注入势垒,引入空穴注入层2T-NATA提高了器件的发光亮度和效率。当2T-NATA厚度为15nm时,器件的效果最好,起亮电压只需2.87V,亮度最高达到18000cd/m2,是不引入空穴注入层亮度的5倍多,在12V时发光效率可达11.4cd/A。 展开更多
关键词 空穴注入层 2T—nata 有机电致发光器件 发光效率 真空蒸镀
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Optimal Ultrasonic Extraction of Pachyman from Jiuzihe Poria cocos 被引量:7
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作者 刘丽 徐春 +2 位作者 李可 姜昆 吴鹏 《Agricultural Science & Technology》 CAS 2016年第12期2746-2750,2776,共6页
This study was conducted to extract pachyman to the greatest degree with ultrasonic technology, and to determine the content of pachyman by the phe-nol-sulfuric acid method, so as to choose the optimal technique of ul... This study was conducted to extract pachyman to the greatest degree with ultrasonic technology, and to determine the content of pachyman by the phe-nol-sulfuric acid method, so as to choose the optimal technique of ultrasonic extrac-tion of pachyman. Firstly, the ultrasonic power, extraction time and solid-to-liquid ra-tio were investigated by ultrasonic extraction method. Then, on this basis, a respon-sible surface experiment was designed, to select the optimal process conditions ac-cording to the index of pachyman yield. The optimized ultrasonic water extraction conditions were as fol ow: ultrasonic power of 100 W, extraction time of 30 min, and solid-to-liquid ratio at 1:40. The Oxford cup method was used to study the an-timicrobial activity of pachyman. lt was found that pachyman could significantly in-hibit Bacilus subtilis_and Staphylococcus aureus. 展开更多
关键词 Poria cocos Pachyman Ultrasonic extraction Response surface An-timicrobial activity
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加拿大CoCo委员会内部控制框架述评 被引量:11
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作者 王展翔 《商业研究》 北大核心 2005年第1期168-171,共4页
加拿大CoCo委员会的内部控制框架是目前世界上最具影响力的内部控制理论框架之一。目的、承诺、能力、监控和学习四个基本内部控制要素以及在此基础上衍生出的20条核心原则是COCo委员会内部控制框架的主要特色。此外,coC0委员会还在内... 加拿大CoCo委员会的内部控制框架是目前世界上最具影响力的内部控制理论框架之一。目的、承诺、能力、监控和学习四个基本内部控制要素以及在此基础上衍生出的20条核心原则是COCo委员会内部控制框架的主要特色。此外,coC0委员会还在内部控制的定义、内部控制与管理活动的关系以及内部控制的作用等方面有着独到的见解。 展开更多
关键词 coco委员会 内部控制框架 内部控制原则
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空穴缓冲层2T-NATA厚度对OLED器件性能的影响 被引量:5
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作者 牟强 王秀峰 张麦丽 《液晶与显示》 CAS CSCD 北大核心 2008年第6期680-683,共4页
在有机电致发光器件中,载流子的注入和匹配水平直接影响着器件性能。在器件中引入空穴缓冲传输层2T-NATA,能够有效改善阳极与有机层的接触,改变有机层中的势垒分布,提高载流子的注入和平衡水平,使激子复合率得到有效改善,从而使器件发... 在有机电致发光器件中,载流子的注入和匹配水平直接影响着器件性能。在器件中引入空穴缓冲传输层2T-NATA,能够有效改善阳极与有机层的接触,改变有机层中的势垒分布,提高载流子的注入和平衡水平,使激子复合率得到有效改善,从而使器件发光特性大幅提高。 展开更多
关键词 空穴缓冲层 2T-nata 发光效率
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不同等级茯苓块、茯苓片的外观性状与内在成分的相关性研究
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作者 黄佳静 房悦 +5 位作者 王妍妍 张越 王雷 俞年军 彭代银 陈卫东 《中南药学》 2025年第1期78-83,共6页
目的探究不同等级茯苓块、茯苓片外观性状与内在成分之间的关系,为茯苓质量评价提供科学依据。方法依据2020年版《中国药典》规定,收集不同等级的茯苓块及茯苓片,通过市场调研将茯苓块分为选货一等、选货二等和统货,茯苓片分为选货和统... 目的探究不同等级茯苓块、茯苓片外观性状与内在成分之间的关系,为茯苓质量评价提供科学依据。方法依据2020年版《中国药典》规定,收集不同等级的茯苓块及茯苓片,通过市场调研将茯苓块分为选货一等、选货二等和统货,茯苓片分为选货和统货,按照药典要求测定浸出物和总灰分含量,同时测定活性成分水溶性多糖、碱溶性多糖及总三萜酸的含量,并对内在指标进行相关性分析。结果茯苓块选货一等的浸出物、总灰分、水溶性多糖和总三萜酸含量显著低于统货,而碱溶性多糖含量显著高于统货;茯苓片选货的浸出物、总灰分、水溶性多糖显著低于统货,总三萜酸含量差异无统计学意义,而碱溶性多糖含量显著高于统货。相关性分析显示,碱溶性多糖含量与总灰分、水溶性多糖含量成显著负相关。结论市场上不同等级茯苓饮片的划分依据与水溶性多糖和总三萜酸含量无关,而与碱溶性多糖含量有关,本研究为茯苓的质量评价提供了参考。 展开更多
关键词 茯苓块 茯苓片 外观性状 等级 内在成分
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加拿大COCO指南与美国COSO报告的比较分析 被引量:3
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作者 吴粒 徐跃 《经济论坛》 2007年第18期139-140,共2页
近年来,加拿大的职业会计师团体、证券监管当局出台了一系列涉及内部控制规范的文告来规范加拿大企业的内部控制系统和程序。其中,最著名的当属加拿大特许会计师协会(Canadian Instituteof Chartered Accountants)负责的控制规范委... 近年来,加拿大的职业会计师团体、证券监管当局出台了一系列涉及内部控制规范的文告来规范加拿大企业的内部控制系统和程序。其中,最著名的当属加拿大特许会计师协会(Canadian Instituteof Chartered Accountants)负责的控制规范委员会(Criteriaof Control Board,简写为COCO)发布的“控制指南”(Guidanceon Control,以下简称“COCO指南”)。COCO专门对控制系统的设计、评估和报告进行研究和发布指南。它对指导和规范企业内部控制提出了很多创新的意见。 展开更多
关键词 coco 加拿大 COSO报告 指南 内部控制系统 内部控制规范 特许会计师协会 美国
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