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Effects of Crops, Soil Types and Irrigation Methods on Digestion Capacity of Biogas Slurry 被引量:5
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作者 高立洪 李平 +1 位作者 韦秀丽 翟逸 《Agricultural Science & Technology》 CAS 2015年第8期1712-1715,共4页
In the research, pot experiment and field testing were conducted to study the effect of different crops, soil types, and irrigation modes on biogas slurry diges- tions. The results showed that when silage maize, sweet... In the research, pot experiment and field testing were conducted to study the effect of different crops, soil types, and irrigation modes on biogas slurry diges- tions. The results showed that when silage maize, sweet sorghum and Chinese cabbage were planted in purple soils, the quantities of digested biogas slurry were of 57, 157.5, and 34.5 t/hm2, respectively, while the quantities of digested biogas slurry were 70.5, 157.5 and 40.5 t/hm2 in yellow soils. Besides, the digested biogas slurries reached 36 and 27 t/hm2 as per flood irrigation and sprinkling irrigation when Chinese cabbages were planted in yellow soils. The research indicated crop variety, soil type, and irrigation method all have effects on farmland digestion of biogas slurry. 展开更多
关键词 CROPS Soil types Irrigation methods Biogas slurry digestion
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Effect of the chlortetracycline addition method on methane production from the anaerobic digestion of swine wastewater 被引量:4
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作者 Lu Huang Xin Wen +5 位作者 Yan Wang Yongde Zou Baohua Ma Xindi Liao Juanboo Liang Yinbao Wu 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2014年第10期2001-2006,共6页
Effects of antibiotic residues on methane production in anaerobic digestion are commonly studied using the following two antibiotic addition methods:(1) adding manure from animals that consume a diet containing ant... Effects of antibiotic residues on methane production in anaerobic digestion are commonly studied using the following two antibiotic addition methods:(1) adding manure from animals that consume a diet containing antibiotics, and(2) adding antibiotic-free animal manure spiked with antibiotics. This study used chlortetracycline(CTC) as a model antibiotic to examine the effects of the antibiotic addition method on methane production in anaerobic digestion under two different swine wastewater concentrations(0.55 and 0.22 mg CTC/g dry manure). The results showed that CTC degradation rate in which manure was directly added at 0.55 mg CTC/g(HSPIKE treatment) was lower than the control values and the rest of the treatment groups. Methane production from the HSPIKEtreatment was reduced(p 〈 0.05) by 12% during the whole experimental period and 15% during the first 7 days. The treatments had no significant effect on the pH and chemical oxygen demand value of the digesters, and the total nitrogen of the0.55 mg CTC/kg manure collected from mediated swine was significantly higher than the other values. Therefore, different methane production under different antibiotic addition methods might be explained by the microbial activity and the concentrations of antibiotic intermediate products and metabolites. Because the primary entry route of veterinary antibiotics into an anaerobic digester is by contaminated animal manure, the most appropriate method for studying antibiotic residue effects on methane production may be using manure from animals that are given a particular antibiotic, rather than adding the antibiotic directly to the anaerobic digester. 展开更多
关键词 Chlortetracycline Methane production Psychrophilic anaerobic digestion Addition methods
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The determination of 52 elements in marine geological samples by an inductively coupled plasma optical emission spectrometry and an inductively coupled plasma mass spectrometry with a high-pressure closed digestion method 被引量:16
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作者 GAO Jingjing LIU Jihua +3 位作者 LI Xianguo YAN Quanshu WANG Xiaojing WANG Hongmin 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2017年第1期109-117,共9页
An improved analytical method to determine the content of 52 major, minor and trace elements in marine geological samples, using a HF-HCl-HNO_3 acid system with a high-pressure closed digestion method(HPCD), is stud... An improved analytical method to determine the content of 52 major, minor and trace elements in marine geological samples, using a HF-HCl-HNO_3 acid system with a high-pressure closed digestion method(HPCD), is studied by an inductively coupled plasma optical emission spectrometry(ICP-OES) and an inductively coupled plasma mass spectrometry(ICP-MS). The operating parameters of the instruments are optimized, and the optimal analytical parameters are determined. The influences of optical spectrum and mass spectrum interferences, digestion methods and acid systems on the analytical results are investigated. The optimal spectral lines and isotopes are chosen, and internal standard element of rhodium is selected to compensate for matrix effects and analytical signals drifting. Compared with the methods of an electric heating plate digestion and a microwave digestion, a high-pressure closed digestion method is optimized with less acid, complete digestion,less damage for digestion process. The marine geological samples are dissolved completely by a HF-HCl-HNO_3 system, the relative error(RE) for the analytical results are all less than 6.0%. The method detection limits are 2–40μg/g by the ICP-OES, and 6–80 ng/g by ICP-MS. The methods are used to determine the marine sediment reference materials(GBW07309, GBW07311, GBW07313), rock reference materials(GBW07103, GBW07104,GBW07105), and cobalt-rich crust reference materials(GBW07337, GBW07338, GBW07339), the obtained analytical results are in agreement with the certified values, and both of the relative standard deviation(RSD) and the relative error(RE) are less than 6.0%. The analytical method meets the requirements for determining 52 elements contents of bulk marine geological samples. 展开更多
关键词 marine geological sample high-pressure closed digestion method inductively coupled plasma optical emission spectrometry inductively coupled plasma mass spectrometry major element minor element trace element
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A Comparative Study of the Difference Method and the Enzyme-Hydrolyzed Casein Method for Determining True Amino Acid Digestibilities and Endogenous Amino Acid Losses in Duck Feed 被引量:1
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作者 GuangtaoGuo KangningWang XiaLi 《Journal of Animal Science and Biotechnology》 SCIE CAS 2010年第2期101-107,共7页
In this study, we examined the varia- tions between the difference method and the enzyme- hydrolyzed casein method for determining endogenous amino acid loss and the true amino acid digestibility in ducks fed normal p... In this study, we examined the varia- tions between the difference method and the enzyme- hydrolyzed casein method for determining endogenous amino acid loss and the true amino acid digestibility in ducks fed normal protein-containing diets. These methods were compared to the nitrogen-free (N-free) diet method. The difference method was based on soy- bean meal as the only protein source, with the experi- mental diets containing crude protein levels at 15% and 20%. The enzyme-hydrolyzed casein method was based on enzyme-hydrolyzed casein meal as the pro- tein source, with the experimental diet containing a crude protein level of 17.5%. The N-free diet was prepared with starches and paper fibers. In each meth- od,64 Tianfu meat drakes (7-weeks-old) with an av- erage body weight of 2.77±0.16 kg were used and divided into four groups, and fed four different diets. Each group contained four replicates of four drakes and they were force fed trial diets according to the Sirbald method for detecting their apparent amino aciddigestibility, endogenous amino acid loss and true a- mino acid digestibility. The results demonstrated that using the difference, enzyme-hydrolyzed casein and N-free diet methods, endogenous amino acid losses were 0. 9946,1. 2243 and 0. 9297 mg/g dry matter in- take ( DMI), respectively. The true amino acid digest- ibility measured by the difference method was 88.93 %±4.43 %. Using the enzyme-hydrolyzed ca- sein method with two dietary crude protein levels of 15% and 20%, the digestibility was 91.15%±4.33% and 91.97%±4. 16%, respectively, and by the N-free diet methods with two dietary crude protein levels of 15% and 20% ,it was 88.55%±4.29% and 88.82 %±4.61%, respectively. The results suggested that when the dietary protein level was 15% to 20 %, the true amino acid digestibility and endogenous ami- no acid loss as determined by the difference method was more accurate than the values determined by the enzyme-hydrolyzed casein method. 展开更多
关键词 casein enzymolysis method difference method DRAKE endogenous amino acid loss true amino acid digestibility
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Methodological impact of starch determination on starch content and ileal digestibility of starch in grain legumes for growing pigs 被引量:3
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作者 Dagmar Jezierny Rainer Mosenthin +2 位作者 Nadja Sauer Klaus Schwadorf Pia Rosenfelder-Kuon 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2017年第2期459-466,共8页
Background: Grain legumes represent a valuable energy source in pig diets due to their high starch content. The present study was conducted to determine the content and apparent ileal digestibility(AID) of starch i... Background: Grain legumes represent a valuable energy source in pig diets due to their high starch content. The present study was conducted to determine the content and apparent ileal digestibility(AID) of starch in different grain legume cultivars for pigs by means of both a polarimetric and enzymatic method for starch determination.Methods: Three experiments were conducted with six barrows each which were fitted with ileal T-cannulas. In total, 18 diets including six different cultivars of faba beans(Vicia faba L.) and peas(Pisum sativum L.), five different cultivars of lupins(Lupinus luteus L., Lupinus angustifolius L.), and one diet with a soybean meal(SBM) were fed.Results: The starch content of faba beans and peas was greater(P &lt; 0.05) when determined polarimetrically than enzymatically(438 vs. 345 g/kg dry matter(DM) in faba beans and 509 vs. 390 g/kg DM in peas, respectively).Considerable lower starch contents were obtained in lupins and SBM, with 82 and 48 g/kg DM(analyzed polarimetrically) and &lt;1.1 and 3 g/kg DM(analyzed enzymatically), respectively. Mean values for contents of neutral detergent fiber(NDF) and acid detergent fiber(ADF) in grain legumes ranged from 111 and 79 g/kg DM in peas to248 and 207 g/kg DM in lupins, respectively. Contents of condensed tannins in the colored flowered faba bean cultivars ranged from 2.1 to 7.4 g/kg DM. The AID of starch was greater(P &lt; 0.05) in pea than in faba bean cultivars,and using the polarimetric starch determination method resulted in greater(P &lt; 0.05) digestibility values than using enzymatic starch analysis(84 vs. 80% in faba beans and 86 vs. 83% in peas). Moreover, AID of starch differed(P &lt; 0.05)within pea cultivars and starch digestibility in faba beans decreased linearly(P &lt; 0.05) as the content of condensed tannins increased. However, there was no relationship between contents of NDF and ADF and AID of starch in pea and faba bean cultivars.Conclusion: Both contents and AID of starch in grain legumes can vary as influenced by the analytical method used for starch determination. Generally, starch digestibility is greater when measured by polarimetric rather than enzymatic methods. 展开更多
关键词 Grain legumes Growing pigs Ileal starch digestibility Starch determination method
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Effects of dietary oil sources and fat extraction methods on apparent and standardized ileal digestibility of fat and fatty acids in growing pigs 被引量:1
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作者 Lu Wang Wenjun Gao +3 位作者 Junyan Zhou Huangwei Shi Tenghao Wang Changhua Lai 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2023年第2期760-770,共11页
Background:There is a lack of data for the standardized ileal digestibility(SID) of fat and fatty acids in national feed databases.In addition,it is important to specify the procedures used for fat analyses.Therefore,... Background:There is a lack of data for the standardized ileal digestibility(SID) of fat and fatty acids in national feed databases.In addition,it is important to specify the procedures used for fat analyses.Therefore,an experiment was conducted to 1) determine the apparent ileal digestibility(AID) and SID of fat and fatty acids in ten different oil sources for growing pigs and to develop prediction equations for SID of fat based on fatty acid composition;and 2) compare the effect of the fat extraction methods on the calculated values for endogenous loss and digestibility of fat.Methods:Twenty-two barrows(initial body weight:32.1 ± 2.3 kg) were surgically fitted with a T-cannula in the distal ileum,and allotted to 1 of 11 experimental diets in a 4-period Youden Square design.A fat-free diet was formulated using cornstarch,soy protein isolate and sucrose.Ten oil-added diets were formulated by adding 6% of dietary oil sources to the fat-free diet at the expense of cornstarch.All diets contained 26% sugar beet pulp and 0.40% chromic oxide.Results:The endogenous loss of ether extract(EE) was lower than that of acid-hydrolyzed fat(AEE;P < 0.01).There were significant differences in the AID and SID of fat and saturated fatty acids across the dietary oil sources(P < 0.05).The SID of AEE for palm oil was lower than that of sunflower oil,corn oil,canola oil,rice oil and flaxseed oil(P < 0.01).The AID and SID of fat ranged from 79.65% to 86.97% and from 91.14% to 99.18%.Although the AID of EE was greater than that of AEE(P < 0.01),there was no significant difference in SID of EE and AEE except for palm oil.The ratio of unsaturated to saturated fatty acids(U/S) had a positive correlation with SID of fat(P < 0.05),whereas C16:0 and long chain saturated fatty acids(LSFA) were significant negatively correlated with SID of fat(P < 0.01).The best-fit equation to predict SID of fat was SID AEE = 102.75-0.15 × LSFA-0.74 × C18:0-0.03 × C18:1(Adjusted coefficient of determination = 0.88,P < 0.01).Conclusions:When calculating the SID of fat,the EE content of the samples can be analyzed using the direct extraction method,whereas the acid hydrolysis procedure should be used to determine the AID of fat.Fat digestibility of dietary oils was affected by their fatty acid composition,especially by the contents of C16:0,LSFA and U/S. 展开更多
关键词 Fat extraction methods Fatty acids Growing pigs Ileal digestibility Oil sources
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Scientific connotation of “treating different diseases with the same method” from the perspective of metabolic-immune dysregulation in inflammation-mediated carcinogenesis of digestive organs 被引量:1
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作者 Xia Ding Yunze Liu +2 位作者 Ruilin Wang Hong Shen Qi Wang 《Journal of Traditional Chinese Medical Sciences》 CAS 2023年第1期3-9,共7页
Inflammation-mediated carcinogenesis develops in the context of chronic inflammation and is a significant cause of cancer within the digestive system.In the chronic inflammation microenvironment,the metabolic activity... Inflammation-mediated carcinogenesis develops in the context of chronic inflammation and is a significant cause of cancer within the digestive system.In the chronic inflammation microenvironment,the metabolic activity of tissue cells undergoes extensive changes,which interfere with the normal function of immune cells.Dysregulation of cell metabolism and immune function has been identified as a key factor contributing to inflammation-mediated carcinogenesis within the major digestive organs,such as the stomach,liver,and colorectum.This metabolic-immune imbalance also corresponds to traditional Chinese medicine(TCM)theories of“yin-yang disharmony”and“disharmony between Ying-nutrients and Wei-defense.”The metabolic-immune imbalance has also been regarded as the key factor supporting“treatment of different diseases with the same method”,in which the same approach is adopted in the treatment of different conditions.In the TCM treatment process,it is necessary to first identify TCM patterns and then apply the corresponding TCM to correct the dysregulated metabolic and immune function,thereby blocking the progression from inflammation to malignancy.Our study findings deepen the TCM understanding of metabolic-immune dysregulation and the relationship between metabolic-immune dysregulation,pattern identification,and treatment method.They also provide new insights for the treatment of inflammation-mediated carcinogenesis in major digestive organs and help us further explore the scientific connotation of the TCM strategy of“treating different diseases with the same method”. 展开更多
关键词 Inflammation-mediated carcinogenesis Treating different diseases with the same method Metaboliceimmune regulation Metabolism Immunity digestive system
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Experimental Study on Anaerobic Digestion of Remaining Sludge in Municipal Wastewater Treatment Plant
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作者 Li Jia Yang Hong 《Journal of Architectural Research and Development》 2018年第4期8-11,共4页
Along with the development and progress of environmental protection management,it is necessary to pay full attention to the disposal of excess sludge in the process of urban sewage treatment plant management.It is nec... Along with the development and progress of environmental protection management,it is necessary to pay full attention to the disposal of excess sludge in the process of urban sewage treatment plant management.It is necessary to ensure effective integration of management mechanisms and management paths.To a certain extent,it can improve the actual efficiency of digestion and treatment work and lay a foundation for the optimal operation of environmental protection management.In this paper,the treatment of excess sludge in a sewage treatment plant is studied.The method and results of anaerobic digestion test of excess sludge in a sewage treatment plant are discussed for reference only. 展开更多
关键词 urban SEWAGE treatment plant excess SLUDGE ANAEROBIC digestion test method result
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Analysis of Nursing Cooperation Methods in the Treatment of Intestinal Polyps under Digestive Endoscopy
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作者 YUChunyan 《外文科技期刊数据库(文摘版)医药卫生》 2022年第3期001-004,共4页
Objective: this study mainly studies the treatment of patients with intestinal polyps, and conducts the treatment process under the control of gastrointestinal endoscopy, in order to improve the treatment effect of th... Objective: this study mainly studies the treatment of patients with intestinal polyps, and conducts the treatment process under the control of gastrointestinal endoscopy, in order to improve the treatment effect of these patients, shorten the treatment time and recovery time of the patients, and improve the life of the patients. quality. Methods: This study selected 72 patients with intestinal polyps who came to our hospital from November 2020 to January 2022. All patients received intestinal polyp treatment as part of gastrointestinal endoscopy. In order to observe the research results, the selected patients were compared and examined in order to better observe the research results. During the examination of all selected patients, the nursing effect and the occurrence of adverse events should be carefully recorded and compared. At the same time, before nursing the selected patients, professional medical staff will evaluate the overall condition of the patients to ensure that the patients can cooperate in the process of this study, and then they can be included in the study. Patients should also take the initiative to inform patients of the research content and purpose, and the research results can be published only with the consent of patients. Results: two different nursing methods had different effects on selected patients, but relatively high-quality nursing methods were preferred by patients, which minimized adverse reactions during the patient's recovery. There were differences in the results across all patients, which better support the data from this study. 展开更多
关键词 digestive endoscopy intestinal polyps nursing method nursing effect
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电感耦合等离子质谱(ICP-MS)法测定稀土矿石中稀土元素 被引量:4
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作者 徐进力 陈润莎 +3 位作者 陈卫明 张鹏鹏 杜雪苗 白金峰 《中国无机分析化学》 北大核心 2025年第5期644-651,共8页
稀土元素(REE)是现代高科技领域不可或缺的功能材料,稀土矿石中稀土成分的准确分析对于资源开发和应用具有重要意义。通过考察两种稀土矿石样品的前处理方法:氢氧化钠-过氧化钠体系碱熔法和盐酸-硝酸-氢氟酸-高氯酸-硫酸(五酸)敞开酸溶... 稀土元素(REE)是现代高科技领域不可或缺的功能材料,稀土矿石中稀土成分的准确分析对于资源开发和应用具有重要意义。通过考察两种稀土矿石样品的前处理方法:氢氧化钠-过氧化钠体系碱熔法和盐酸-硝酸-氢氟酸-高氯酸-硫酸(五酸)敞开酸溶法,并利用电感耦合等离子体质谱仪(ICP-MS)对稀土元素进行测定。实验表明,碱熔法在消解复杂基体的稀土矿石样品时具有更高的消解效率和更好的精密度(RSD≤4%),尽管其样品空白本底值略高于五酸消解法,基本不影响分析结果的准确度。通过优化仪器工作参数,建立了准确度、精密度高的分析方法。方法的检出限低(如Y为0.02μg/g,Lu为0.001μg/g),精密度良好(RSD小于3%),相对误差(RE)小于11%,适用于稀土矿石中稀土元素的准确测定。研究表明,碱熔法是稀土矿石样品前处理的优选方法,而五酸消解法可作为对比验证手段,可确保分析数据的可靠性。ICP-MS的高效性和准确性使其成为稀土元素分析的理想工具,为稀土资源的开发和研究提供了有力的技术支持。 展开更多
关键词 稀土元素 稀土矿石 碱熔 酸溶 电感耦合等离子体质谱
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器官—系统整合医学消化区段知识课程线上教学的探索
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作者 杨沛刚 赵雪峰 +4 位作者 檀碧波 王冬 郭洪海 丁平安 赵群 《中国高等医学教育》 2025年第1期87-89,共3页
目的:探讨线上教学在消化系统课程整合中的应用效果。方法:选取2020年9月至2021年9月接受消化系统整合医学教学的临床本科生48名,所有学生在进入胃肠外科实习前均未接触过线上教学模式,并随机分为对照组和试验组,每组各24人。对照组采... 目的:探讨线上教学在消化系统课程整合中的应用效果。方法:选取2020年9月至2021年9月接受消化系统整合医学教学的临床本科生48名,所有学生在进入胃肠外科实习前均未接触过线上教学模式,并随机分为对照组和试验组,每组各24人。对照组采取单纯线下教学模式,试验组采取线下联合线上教学模式。培训结束比较两组理论水平、技能操作水平、临床问题解决能力以评估培训效果。结果:试验组理论知识水平的平均成绩为(84.46±3.43)分,对照组为(83.79±3.56)分,两组差异无统计学意义(P=0.512)。试验组技能操作的得分为(86.54±2.67)分,对照组得分为(82.33±2.79)分,两组差异有统计学意义(P<0.001)。试验组临床胜任力的得分为(87.88±2.94)分,对照组的得分为(83.46±3.02)分,两组差异有统计学意义(P<0.001)。结论:线上课程的开展对消化系统整合课程教学起到补充、促进作用,可全方位培养学生的动手能力、综合分析能力及批判性思维能力。 展开更多
关键词 整合医学 消化系统 教学方式 线上模拟教学
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干燥方式对仿生法测定猪饲料氨基酸消化率的影响
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作者 曹宁 张虎 +7 位作者 王俊丽 萨仁娜 赵峰 解竞静 高理想 赵江涛 董莹 王钰明 《畜牧兽医学报》 北大核心 2025年第8期3893-3907,共15页
本试验旨在研究6种干燥方式对仿生消化法测定猪饲料氨基酸消化率及其可加性的影响,从而为饲料氨基酸效价快速评定方法的建立提供参考。试验采取随机区组设计,选用5种试验饲粮(4种猪常用的饲料原料:玉米、小麦、豆粕、小麦麸,以及以上述... 本试验旨在研究6种干燥方式对仿生消化法测定猪饲料氨基酸消化率及其可加性的影响,从而为饲料氨基酸效价快速评定方法的建立提供参考。试验采取随机区组设计,选用5种试验饲粮(4种猪常用的饲料原料:玉米、小麦、豆粕、小麦麸,以及以上述4种原料配制的全价饲粮),经过体外模拟消化后的残渣采用6种干燥方式进行后处理:处理1:55℃风干+同步测水分;处理2:55℃风干+105℃绝干;处理3:65℃风干+同步测水分;处理4:65℃风干+105℃绝干;处理5:65℃风干(加2 mL 1 mol·L^(-1)盐酸)+105℃绝干;处理6:冻干。对不同干燥方式处理后的样品进行称重和氨基酸含量测定,计算干物质和氨基酸消化率,同时以无氮饲粮测定的内源损失将其校正到标准氨基酸消化率。每个处理每种饲粮5个重复,每个重复1根消化管。结果表明:1)玉米、小麦和全价饲粮的干物质消化率在6种干燥方式间均无显著差异(P>0.05);但是在豆粕上处理6的干物质消化率显著高于处理2、处理4、处理5(P<0.05);在小麦麸上处理3、处理5的干物质消化率显著高于其余4个处理组(P<0.05);2)在豆粕和全价饲粮上,6种干燥方式间的氨基酸消化率均无显著差异(P>0.05);在玉米上,处理3、处理6的氨基酸消化率显著低于处理5(P<0.05);在小麦上,处理1和处理3的氨基酸消化率显著高于其他4个处理组(P<0.05);在小麦麸上,处理3、处理4和处理5的氨基酸消化率显著高于其他3个处理组(P<0.05)。进一步,以原料和饲粮为区组的分析结果表明,6种干燥方式间的氨基酸消化率无显著差异(P>0.05);3)全价饲粮可消化氨基酸含量的计算值与实测值在处理2与处理6上的相对偏差均小于5%,且与Y=X相比斜率无显著差异(P>0.05)。综上,在采用仿生消化法评定猪饲料的氨基酸消化率时,55℃风干+105℃绝干的干燥方式处理消化残渣与冻干法相近,且具有较好的可加性。 展开更多
关键词 仿生消化 氨基酸消化率 干燥方式 可加性 生长猪
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不同浸泡方式对米饭食用品质和消化特性的影响
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作者 沙文轩 谢强 +3 位作者 史守纪 王娜 袁梦 周晓燕 《美食研究》 北大核心 2025年第1期63-69,共7页
为研究不同浸泡方式对米饭食用品质和消化特性的影响,利用卡路里量热仪、色差仪、质构仪等仪器分别对不同浸泡方式处理的米饭进行品质分析,并采用体外消化实验对米饭的淀粉组成、体外血糖生成指数和蛋白消化特性进行测定。结果表明:低... 为研究不同浸泡方式对米饭食用品质和消化特性的影响,利用卡路里量热仪、色差仪、质构仪等仪器分别对不同浸泡方式处理的米饭进行品质分析,并采用体外消化实验对米饭的淀粉组成、体外血糖生成指数和蛋白消化特性进行测定。结果表明:低压浸泡的米饭感官品质最好,具有较低的血糖生成指数值;酶法浸泡处理的米饭蛋白质消化率最高,亮度和白度最高,但感官评分最低;超声浸泡处理的米饭在感官评分更接近于常规浸泡的米饭,具有最高的吸水率和膨胀率。本研究为通过不同浸泡方式改善米饭的食用品质提供理论依据和数据支持。 展开更多
关键词 浸泡方式 米饭 淀粉消化 蛋白消化 食用品质
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ICP-MS法测定松花粉无机元素含量及安全性、健康风险评估 被引量:1
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作者 刘浩 郭海涛 +5 位作者 姬爱熙 李姝琪 余少君 杨国华 刘卓尔 刘永刚 《河北科技大学学报》 北大核心 2025年第1期67-76,共10页
为测定松花粉中18种无机元素的含量,并对重金属及有害元素进行安全性和健康风险评估,采用微波消解法处理样品,利用电感耦合等离子体质谱法(ICP-MS法)进行测定,使用软件Origin 2021和微生信平台绘制松花粉无机元素特征谱图和相关系数矩阵... 为测定松花粉中18种无机元素的含量,并对重金属及有害元素进行安全性和健康风险评估,采用微波消解法处理样品,利用电感耦合等离子体质谱法(ICP-MS法)进行测定,使用软件Origin 2021和微生信平台绘制松花粉无机元素特征谱图和相关系数矩阵图,通过计算重金属元素的单项污染指数P_(i)对松花粉的安全性进行评估,计算重金属元素的每日最大可耐受量、靶标危害系数和致癌风险,并对松花粉的健康风险进行评估。结果表明:松花粉中主要含有Na、Mg、K、Ca、Fe、Zn 6种无机元素;P_(i)结果显示松花粉样品未被污染,水平优良;松花粉样品中重金属及有害元素未对暴露人群产生健康风险。采用ICP-MS法对松花粉中18种无机元素进行测定分析,可为松花粉的质量安全评价和推广应用提供一定的理论依据。 展开更多
关键词 化学分析 松花粉 无机元素 重金属及有害元素 微波消解法 ICP-MS法
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聚乙二醇和八聚精氨酸双修饰漆黄素脂质体的制备、表征及体内外评价 被引量:2
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作者 姚杰 姬新颖 +3 位作者 张体鹏 时艳华 杜娟 张付利 《中草药》 北大核心 2025年第5期1564-1579,共16页
目的制备聚乙二醇(PEG)和八聚精氨酸(R8)双修饰漆黄素脂质体(PEG and R8 co-modified fisetin liposomes,PEG/R8-Fis-Lips),对其进行理化表征,并考察其口服相对生物利用度和改善急性肝损伤作用。方法合成二硬脂酰磷脂酰乙醇胺-聚乙二醇2... 目的制备聚乙二醇(PEG)和八聚精氨酸(R8)双修饰漆黄素脂质体(PEG and R8 co-modified fisetin liposomes,PEG/R8-Fis-Lips),对其进行理化表征,并考察其口服相对生物利用度和改善急性肝损伤作用。方法合成二硬脂酰磷脂酰乙醇胺-聚乙二醇2000-八聚精氨酸(DSPE-mPEG2000-R8)并进行核磁共振氢谱(1H-NMR)确认。采用后插入法制备PEG/R8-Fis-Lips;HPLC法测定漆黄素含量并计算包封率及载药量;单因素考察PEG/R8-Fis-Lips处方工艺,采用Box-Behnken设计-响应面法(Box-Behnken design-response surface method,BBD-RSM)优化PEG/R8-Fis-Lips处方,并采用乳糖将PEG/R8-FisLips混悬液制备成冻干粉;透射电子显微镜(transmission electron microscopy,TEM)观察其形态,X射线粉末衍射法考察冻干粉晶型,考察PEG/R8-Fis-Lips冻干粉在模拟消化液中的稳定性、体外释药行为及贮存稳定性。SD大鼠ig给予PEG/R8-Fis-Lips后采血,考察其口服药动学行为;建立急性肝损伤模型,考察PEG/R8-Fis-Lips改善急性肝损伤作用。结果成功合成了DSPE-mPEG2000-R8。PEG/R8-Fis-Lips最佳处方:磷脂与胆固醇用量比为6.0∶1,总脂质与药物用量比为12.5∶1,DSPEm PEG2000-R8质量浓度为0.26 mg/mL;PEG/R8-Fis-Lips的包封率、载药量、粒径和ζ电位分别为(86.17±0.20)%、(6.01±0.10)%、(253.75±13.14)nm、(-14.16±0.82)m V,PEG/R8-Fis-Lips外观为球形及类球形。漆黄素在PEG/R8-Fis-Lips冻干粉中以无定型状态存在,PEG/R8-Fis-Lips在模拟消化液中的稳定性及累积释放率均高于漆黄素原料药及其普通脂质体(Fis-Lips),其体外释药过程符合Weibull模型;贮存稳定性也明显提高。药动学结果显示,PEG/R8-Fis-Lips达峰浓度(Cmax)增加至(604.05±166.73)ng/mL,半衰期(t1/2)延长至(5.04±0.63)h,相对生物利用度提高至7.71倍;且PEG/R8-Fis-Lips减轻了对乙酰氨基酚所致的急性肝损伤。结论PEG/R8-Fis-Lips极大地促进了漆黄素口服吸收,并增强了漆黄素改善急性肝损伤作用。 展开更多
关键词 漆黄素 脂质体 修饰 后插入法 Box-Behnken设计-响应面法 模拟消化液 药动学 口服生物利用度 急性肝损伤
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全收粪法与回肠食糜法测定鸭饲粮氨基酸消化率的比较研究
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作者 王浩然 朱云 +6 位作者 王俊丽 赵峰 萨仁娜 解竞静 谭会泽 魏师 王钰明 《动物营养学报》 北大核心 2025年第1期330-340,共11页
本试验旨在研究全收粪法与回肠食糜法测定肉鸭内源氨基酸损失、饲粮标准氨基酸消化率的差异及其可加性,为选择更合适的肉鸭饲粮氨基酸效价评定方法提供参考。试验选用48只20周龄雄性北京鸭,随机分为2组:全收粪组和取回肠食糜组,每组采... 本试验旨在研究全收粪法与回肠食糜法测定肉鸭内源氨基酸损失、饲粮标准氨基酸消化率的差异及其可加性,为选择更合适的肉鸭饲粮氨基酸效价评定方法提供参考。试验选用48只20周龄雄性北京鸭,随机分为2组:全收粪组和取回肠食糜组,每组采用单因素完全随机区组设计,包括4个饲粮处理:以玉米和豆粕分别为唯一蛋白质源配制的玉米饲粮和豆粕饲粮、玉米-豆粕型全价饲粮以及1种无氮饲粮,饲粮中均添加0.5%二氧化钛(TiO_(2))作为指示剂,每个处理6个重复,每个重复1只鸭。采集经肉鸭消化后的粪便或食糜样品,全收粪组通过差量法和指示剂法2种方式、取回肠食糜组通过指示剂法计算得到饲粮标准氨基酸消化率。结果表明:1)通过全收粪-指示剂法测定的无氮饲粮下肉鸭苯丙氨酸、苏氨酸、缬氨酸及总氨基酸的内源损失均显著低于回肠食糜法(P<0.05)。2)全收粪-差量法、全收粪-指示剂法和回肠食糜法测定的玉米饲粮标准氨基酸消化率均有超过100%的氨基酸,3种方法测定的标准氨基酸消化率在玉米饲粮中除蛋氨酸、玉米-豆粕型饲粮中除天冬氨酸和谷氨酸外均无显著差异(P>0.05)。3)单样本t检验表明,回肠食糜法测定的玉米-豆粕型饲粮的可消化氨基酸含量的实测值与计算值间均无显著差异(P>0.05),全收粪-差量法和全收粪-指示剂法测定的玉米-豆粕型饲粮的总可消化氨基酸含量的实测值均显著小于计算值(P<0.05)。由此可见,全收粪法和回肠食糜法测定的饲粮标准氨基酸消化率具有可比性,但回肠食糜法测得的饲粮标准氨基酸消化率的可加性更好。 展开更多
关键词 全收粪法 回肠食糜法 标准氨基酸消化率 可加性
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三种原代提取方法培养人牙囊干细胞的比较研究
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作者 李艾莲 杨芸瑄 +1 位作者 杨雪松 黄跃 《暨南大学学报(自然科学与医学版)》 北大核心 2025年第3期322-333,共12页
目的:比较3种不同原代培养方法对牙囊干细胞产出效能及生物学特性的影响。方法:收集2024年暨南大学附属第一医院口腔外科12~20周岁正畸患者的智齿牙胚,采用酶消法、组织块法、混合法进行原代细胞提取,比较这3组方法所需的经济成本和时... 目的:比较3种不同原代培养方法对牙囊干细胞产出效能及生物学特性的影响。方法:收集2024年暨南大学附属第一医院口腔外科12~20周岁正畸患者的智齿牙胚,采用酶消法、组织块法、混合法进行原代细胞提取,比较这3组方法所需的经济成本和时间成本、原代牙囊干细胞的产出量及其表面免疫标志物、增殖能力、迁移能力及多向分化潜能等生物学特性的差异。结果:在牙囊干细胞产出效能方面,混合法有较大优势,但总操作时间较长;组织块法操作简单,但原代细胞数量产出少。在牙囊干细胞的生物学特性方面,细胞表面免疫标志物、迁移速率、多向分化潜能均无明显差异(P>0.05)。而在增殖能力上,混合法组明显强于组织块法和酶消法(P<0.05),酶消法组最弱(P<0.05)。结论:混合法适用于大规模研究,如细胞治疗和组织工程研究;组织块法操作简单,细胞活性较好,适合小规模研究;酶消法适用于对细胞量有一定要求,但对细胞状态要求不高的实验。本研究结果可为优化牙囊干细胞培养方法提供参考。 展开更多
关键词 牙囊干细胞 组织块法 混合法 酶消法
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斜带石斑鱼肠上皮细胞原代培养及鉴定方法的研究
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作者 徐健铭 杨红玲 +1 位作者 蔡国鹤 孙云章 《动物营养学报》 北大核心 2025年第9期6291-6301,共11页
本研究旨在探究斜带石斑鱼肠上皮细胞原代培养及鉴定方法。以斜带石斑鱼肠道组织为试验材料,选用组织块法和酶消化法分别对细胞进行培养,对比2种培养方法的效果;分别用胰蛋白酶、胶原酶Ⅰ以及胶原酶Ⅰ+胶原酶Ⅳ对斜带石斑肠道组织进行消... 本研究旨在探究斜带石斑鱼肠上皮细胞原代培养及鉴定方法。以斜带石斑鱼肠道组织为试验材料,选用组织块法和酶消化法分别对细胞进行培养,对比2种培养方法的效果;分别用胰蛋白酶、胶原酶Ⅰ以及胶原酶Ⅰ+胶原酶Ⅳ对斜带石斑肠道组织进行消化,比较不同消化酶对细胞的分离效果;选择3种培养基(DMEM、DMEM/F12和L15培养基)以及不同胎牛血清(FBS)浓度[5%、12%、20%],比较不同培养基与FBS浓度对细胞生长的影响;利用形态学观察、透射电镜观察、碱性磷酸酶染色、18S rRNA基因序列比对及肠道细胞标志性基因表达检测等手段,对培养的原代细胞进行鉴定。结果显示:酶消化法与组织块法均能获得贴壁生长的细胞,但酶消化法培养12 d后可见细胞铺满瓶底,而组织块法则在培养28 d后才可见细胞铺满瓶底;0.25 mg/mL胰蛋白酶[含0.91 mmol/L乙二胺四乙酸(EDTA)]消化肠道组织15 min为最佳消化时间,在此条件下既能获得足够的细胞,又能够保持细胞的完整性和活性;细胞在含20%FBS的L15培养基中的增殖率较高。透射电镜观察、碱性磷酸酶染色和肠道细胞标志性基因表达检测结果证实所培养的细胞为肠上皮细胞,18S rRNA基因序列比对证明细胞来源于石斑鱼。由此可见,使用0.25 mg/mL的胰蛋白酶(含0.91 mmo/L EDTA)处理斜带石斑鱼肠道组织15 min后,将获得的细胞置于含20%FBS的L15培养基内培养,此法能有效获得稳定贴壁生长的斜带石斑鱼原代肠上皮细胞。 展开更多
关键词 斜带石斑鱼 肠上皮细胞 原代培养 组织块法 酶消化法
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水系沉积物密闭消解法优化
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作者 徐子微 杭姚明 +3 位作者 张国辉 郭凯 刘世明 郭文牧 《实验室研究与探索》 北大核心 2025年第5期37-41,共5页
为了研究传统密闭消解法对水系沉积物的消解效果,设计正交实验,对比四酸敞罐消解法(硝酸、氢氟酸、高氯酸、硫酸)、三酸密闭消解法(硝酸、氢氟酸、高氯酸)和二酸密闭消解法(硝酸、氢氟酸)在不同消解体系和消解时间下对国家标准物质水系... 为了研究传统密闭消解法对水系沉积物的消解效果,设计正交实验,对比四酸敞罐消解法(硝酸、氢氟酸、高氯酸、硫酸)、三酸密闭消解法(硝酸、氢氟酸、高氯酸)和二酸密闭消解法(硝酸、氢氟酸)在不同消解体系和消解时间下对国家标准物质水系沉积物GBW07309样品中锂、镓和稀土元素消解效果的影响。采用国家标准物质GBW07309和Rh内标法,利用电感耦合等离子体质谱法(ICP-MS)测定GBW07309样品中锂、镓和稀土元素。结果表明,四酸敞罐消解法虽然操作简便,但是消解效果不理想;三酸密闭消解法中,2mL硝酸、4mL氢氟酸、1mL高氯酸体系、消解时间48h时,消解效果最优;二酸密闭消解法中,2mL硝酸、4mL氢氟酸体系、消解时间24h时,消解效果最优;二酸密闭消解法最优体系的消解效果与三酸密闭消解法最优体系相比,二酸密闭消解法最优体系消解效果更佳。 展开更多
关键词 锂、镓和稀土元素 电感耦合等离子体质谱法 四酸敞罐消解法 三酸密闭消解法 二酸密闭消解法
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微波消解-原子荧光法测定土壤硒的测量不确定度评定
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作者 王成艳 赵秋芳 +3 位作者 冼皑敏 魏长宾 马智玲 汤昕明 《广州化工》 2025年第1期115-118,共4页
采用微波消解-原子荧光法对土壤标准物质(GSS-38)中全硒含量进行测定,并对测量结果进行不确定度评定。分析整个检测过程中产生不确定度的来源,发现检测不确定度的来源主要包括样品称量、标准溶液配制、校准工作曲线拟合、试液定容体积... 采用微波消解-原子荧光法对土壤标准物质(GSS-38)中全硒含量进行测定,并对测量结果进行不确定度评定。分析整个检测过程中产生不确定度的来源,发现检测不确定度的来源主要包括样品称量、标准溶液配制、校准工作曲线拟合、试液定容体积及样品测量重复性等分量,并计算了各分量的相对标准不确定度。研究发现测量结果不确定度主要来源于测定溶液定容、标准曲线稀释配制、测量重复性等。采用置信概率为95%,包含因子k=2,原子荧光法测定GSS-38土壤中硒含量的测定结果为(1.34±0.08)mg/kg。 展开更多
关键词 微波消解 原子荧光法 不确定度 土壤
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