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1.
神经节苷脂纯化方法的改进   总被引:3,自引:0,他引:3  
神经节苷脂(ganglioside,Gls)的分离与纯化是研究组织细胞Gls组成、含量及代谢的基本手段。由于Gls在神经以外组织中含量甚微,而且因组织、细胞的不同,影响Gls纯化的因素也不同.在实验过程中常常由于方法选择不当致使实验失敗.本文介绍一种改进的方法,它操作简单,适用于大鼠多种组织,因  相似文献   

2.
开展了从巨尾桉叶中提取皂苷的工艺优化研究.考察了温度、时间,溶剂用量对皂苷得率的影响,并对粗提物进行纯化.结果表明,巨尾桉叶皂苷的优化条件是:提取温度61.8℃,提取时间5.02h,溶剂与巨尾桉叶的液料比为20.09∶1,皂苷的提取得率(g/g)为5.51%.提取物经大孔树脂-丙酮沉淀联用分离法纯化后皂苷含量由16.22%提高到50.35%.对粗提物、大孔树脂纯化物和大孔树脂吸附-丙酮沉淀纯化物进行抗氧化活性研究.结果表明,它们对DPPH自由基的最大清除率分别为83.02%、84.20%和85.62%,对过氧化氢的最大清除率分别为80.10%、55.02%和48.21%,对超氧阴离子自由基的最大清除率分别为16.62%、13.43%和10.01%.  相似文献   

3.
通过正交试验对有柄石韦中黄酮类成分分离纯化工艺进行研究,为有柄石韦的深入开发利用提供基础材料。以黄酮得率为指标,通过单因素和正交试验,对有柄石韦中多糖提取的工艺参数进行优化。在黄酮纯化中影响因素的大小顺序为:萃取溶剂萃取次数溶剂用量萃取时间。有柄石韦中黄酮分离纯化的最佳工艺参数组合为:萃取溶剂为正丁醇,萃取时间30 min,溶剂的量为200 mL,萃取4次。实验验证该工艺可行,稳定。  相似文献   

4.
大孔树脂吸附法纯化黄芪总皂苷的工艺研究   总被引:1,自引:0,他引:1  
采用大孔树脂吸附法富集纯化黄芪总皂苷,以HPLC-ELSD法测定黄芪甲苷的含量作为考察指标,筛选了树脂型号、吸附流速、洗脱溶剂、洗脱流速以及洗脱溶剂用量等工艺条件.结果表明:最佳工艺为选择D101型大孔树脂,吸附流速为2 BV·h-1,洗脱流速为4 BV·h-1,收集5 BV的70%乙醇部分,得到的黄芪总皂苷纯化效果最好,黄芪甲苷的转移率可达93.21%.  相似文献   

5.
总神经节苷脂的简便纯化方法   总被引:1,自引:0,他引:1  
许多研究者先后提出了多种分离纯化神经节苷脂(Gls)的方法,其中Yu等建立的相继用离子交换剂、吸附剂分别层析的方法在国内较为常用,但其周期较长、步骤较繁。本文将离子交换剂与吸附剂装入同一柱内一次完成Gls的层析纯化,并用含盐氯仿(C)-甲醇(M)混合液(C/M=2/7,V/V,含0.1mol/L NaAc)代替Yu法B液进行洗脱,用国产硅胶代替价格昂贵的Iatrobeads,取得了良好的效果。本法的优点是能节省时间及有机溶媒。  相似文献   

6.
凝胶柱层析分离虎杖中白藜芦醇的研究   总被引:4,自引:0,他引:4  
本论文初步探讨了虎杖中白藜芦醇分离纯化的工艺条件,比较了不同溶剂、不同浓度、不同流速洗脱条件下白藜芦醇样品在LH-20凝胶层析柱上的分离效果,以及虎杖的乙醇提取液通过氯仿、乙酸乙酯萃取,凝胶柱层析分离后的成分变化,实验表明,当以甲醇为洗脱液,浓度为60%,流速为0.5 mL/min时,白藜芦醇样品的分离效果最好.采用中压液相色谱检测收集到的白藜芦醇纯度(以白藜芦醇峰面积占总峰面积计算)可达80.34%,回收率达86.16%.  相似文献   

7.
本文建立高速逆流色谱(HSCCC)方法,从白芍粗提物中分离纯化五没食子酰基葡萄糖.分别采用正己烷-乙酸乙酯-甲醇-水体积比0.5∶5∶1∶5及0.5∶5∶0.5∶5混合溶剂作为两相溶剂体系,上相为固定相,下相为流动相,转速为800 rpm,流速为2.0 mL/min,用HPLC检测及ESI-MS进行验证.经过两次HSCCC分离纯化,得到五没食子酰基葡萄糖纯度为95.7%.  相似文献   

8.
目的:研究大孔吸附树脂纯化鸡枞皂苷的方法.方法:采用分光光度法测定鸡枞皂甙的含量,分别考察了树脂种类、样品液浓度、pH值、吸附流速、洗脱剂浓度对鸡枞皂甙分离纯化的影响.结果:HPD-450树脂最适合鸡枞皂苷的纯化.工艺条件为:洗脱剂乙醇的体积分数为40%,吸附流速为1~2mL/min,样品液浓度为2.5~4.0mg/mL,样品液pH值为5~7.采用HPD-450大孔吸附树脂对鸡枞皂甙进行纯化效果最优.结论:在上述条件下,大孔树脂可用于鸡枞皂甙的分离纯化.  相似文献   

9.
利用数学建模的方法首次提出了衡量分离纯化效果优劣的定量指标——纯化效益;建立了便于应用推广的聚乙二醇(polyethyleneglycol,PEG)和硫酸铵沉淀分离纯化模型,并以海芋过氧化物酶分离纯化为例,对模型进行求解、应用和检验,求解最优实验试剂用量.  相似文献   

10.
以雷公藤植物粗提物为原料,建立了高速逆流色谱分离纯化雷公藤红素的分离纯化方法。优化了两相溶剂体系的组成及配比。优化后的分离纯化溶剂体系为正己烷-乙酸乙酯-甲醇-水,其体积之比为2∶3∶3∶2(上相为固定相,下相为流动相),实验温度为室温,主机转速为800 rpm,正向洗脱,流动相流速为2.0 m L/min。目标产物的分离时间较短、产品纯度高(97.5%)、分离过程稳定。  相似文献   

11.
PurposeTo find the optimal dose weighting for hybrid volumetric modulated arc therapy (H-VMAT), a combination of conventional 3DCRT and VMAT plans for left sided chest wall and supraclavicular radiation therapy.Methods & materials20 left-sided breast cancer patients who received adjuvant radiotherapy were considered for this study. To find the optimal weighting, 5 H-VMAT plans were generated for each study case by combining different dose proportions of 3DCRT and VMAT plans including: 90% 3DCRT/10% VMAT, 80% 3DCRT/20% VMAT, 70% 3DCRT/30% VMAT, 60% 3DCRT/40% VMAT, 50% 3DCRT/50% VMAT. Further field-in-field, optimal H-VMAT and VMAT alone plans were compared.ResultsAll H-VMAT plans achieved the expected target coverage. A higher conformity index was achieved for 50% 3DCRT/50% VMAT plan, while better homogeneity index was achieved for 80% 3DCRT/20% VMAT plan. Mean and low doses were less in 90% 3DCRT/10% VMAT plan. Compared with other proportions, 80% 3DCRT/20% VMAT and 70% 3DCRT/30% VMAT weighted H-VMAT plans achieved balanced results for PTVs and OARs.ConclusionThe optimal dose mixture for H-VMAT technique is 70% to 80% for 3DCRT and 20% to 30% for VMAT. The optimal H-VMAT achieved balanced results for the PTVs and OARs compared with field-in-field and VMAT alone plans.  相似文献   

12.
部分小麦育种材料低分子量谷蛋白亚基等位基因变异   总被引:3,自引:0,他引:3  
改进小麦LMW-G S分离技术,利用改良一步单向连续梯度SDS-PAGE技术分析40份具有较好品质、产量特性的小麦育种亲本材料的LMW-G S类型和组成形式。结果表明:采用适当的方法提取谷蛋白亚基,在4.8%浓缩胶(pH 6.8,C=2.6%),12.0%~14.0%连续梯度分离胶浓度(pH 8.8,C=1.3%),电流35 mA,电泳330 m in后可以获得良好的LMW-G S分离效果。G lu-3位点出现11种变异类型、19种亚基组合形式。G lu-A 3位点出现G lu-A 3a、G lu-A 3b、G lu-A 3c、G lu-A 3d 4种类型,频率分别为40.0%、12.5%、10.0%、37.5%;G lu-B 3位点出现7种亚基类型,其中G lu-B 3d、G lu-B 3b、G lu-B 3 j为主要类型,频率分别为40.0%、20.0%、12.5%。亚基组合形式G lu-A 3a G lu-B 3d组合频率最高,频率为22.5%;9个亚基组合分别只在一个亲本出现,占分析材料总数22.5%。G lu-A 3位点的遗传变异指数为0.673 8,G lu-B 3位点的遗传变异指数为0.800 8,表明G lu-3位点遗传变异丰富。  相似文献   

13.
The epididymis of adult rats metabolizes 3H 5alpha-androstane-3alpah,17beta-diol (3alpha-diol) by experiments in vitro. After incubation of tissue slices at 37 degrees C for 2 hours, 2% of the radioactivity was found in the water-soluble fraction whereas 98% was found to be ether soluble (free steroids). Further investigation of the free steroids showed the following to be present: 3alpha-diol 39.9%, DHT (17beta-hydroxy-5alpha-androstan-3-one) 33.7%, androsterone (3alpha-hydroxy-5alpha-androstan-17-one) 9.2%, 3beta-diol (5alpha-androstane-3beta,17beta-diol) 2.6%, 5alpha-A-dione (5alpha-androstan-3,17-dione) 1.1%, delta 16-3alpha-ol (5alpha-androst-16-en-3alpha-ol) 1.0%, delta16-3beta-ol (5alpha-androst-16-en-3beta-ol) 2.6%, delta 16-3-one (5alpha-androst-16-en-3-one) 2.9%, and polar compounds 3.3%. When segments of the epididymis (caput and cauda) were incubated in the same way, qualitatively similar metabolites were formed but a greater amount of 3alpha-diol was metabolized by the cauda epididymis. This increase was mainly accounted for by an increased formation of delta 16 compounds (14.3% in cauda, 4.3% in caput). This is most probably due to the presence of larger numbers of mature spermatozoa, which, as we have previously shown, form delta16 steroids from 3alpha-diol and DHT (5).  相似文献   

14.

Background

Intraoperative radiotherapy (IORT) refers to the delivery of a high dose of radiation at the time of surgery.

Aim

To analyze clinical and research-oriented innovative activities developed in a 17-year period using intraoperative electron-radiation therapy (IOeRT) as a component of treatment in a multidisciplinary approach for cancer management.

Materials and methods

From 01/1995 to 03/2012 IOeRT procedures were registered in a specific Hospital-based database. Research and developments in imaging and recording for treatment planning implementation are active since 2006.

Results

1004 patients were treated and 1036 IORT procedures completed. Median age of patients was 61 (range 5 months to 94 years). Gender distribution was male in 54% of cases and female in 46%. Disease status at the time of IORT was 796 (77%) primary and 240 (23%) recurrent. Cancer type distribution included: 62% gastrointestinal, 18% sarcoma, 5% pancreas, 2% paediatric, 3% breast, 77 7% oligotopic recurrences, 2% other. IORT technical characteristics were: Applicator size 5 cm 22%, 6 cm 21%, 7 cm 21%, 8 cm 15%, 9 cm 6%, 10 cm 7% 12 cm 5% 15 cm 3%. Electron energies: 6 MeV 19%, 8 MeV 15%, 10 MeV 15%, 12 MeV 23%, 15 MeV 19%, 18 MeV 6%, other 3%. Multiple fields: 108 (11%). Dose: 7.5 Gy 3%, 10 Gy 35%, 12 Gy 3%, 12.5 Gy 49%, 15 Gy 5%, other 5%.

Conclusion

An IORT programme developed in an Academic Hospital based on practice-oriented medical decisions is an attractive interdisciplinary oncology initiative proven to be able to generate an intensive clinical activity for cancer patient quality care and a competitive source of scientific patient-oriented research, development and innovation.  相似文献   

15.
Muscle and adipose tissue were obtained from steers and dairy cows following subcutaneous administration of [14C] progesterone. Following extraction, purification and separation by column, thin layer and gas-liquid chromatography, various radioactive residues from these tissues were identified by their Chromatographic mobility, crystallization to constant specific activity and mass spectra. Progesterone constituted 54% of free radioactivity extracted from muscle and 69 and 73% of radioactivity in the free and conjugated portions of extracts, respectively, from fat. Metabolites identified were: 5α-pregnane-3,20-dione, 9%, 0%, 0%, 20β-hydroxy-4-pregnen-3-one, 8%, 11%, 3%; 3α-hydroxy-5β-pregnan-20-one, 13%, 2%, 2%; 3α-hydroxy-5α-pregnan-20-one, 3%, 3%, 6%; 20α-hydroxy-5α-pregnan-3-one, 0%, 2%, 3%; of radioactivity in muscle (free) and fat (free and conjugated fractions), respectively. Tentatively identified in fat extracts by chromatographic mobility were: 20α-hydroxy-4-pregnen-3-one, 1%, 1% and 3β-hydroxy-5β-pregnan-20-one, 0%, 2% of radioactivity in free and conjugated fractions, respectively. The average concentration of steroid in these animals due solely to treatment, calculated from the specific activity of the [14C] progesterone administered, was 3.4 and 18.1 ng/g in muscle and subcutaneous fat, respectively.  相似文献   

16.
本文利用作者建立的密度梯度超速离心分离VLDL的新方法和分析等电聚焦电泳,测定了95例中国人Apo-E基因多态性和其表型分布以及血脂水平。所得表型分布趋势与国外报告一致:E_3/E_3频率最高,E_3/E_2和E_3/E_4次之,E_4/E_4,E_4/E_2和E_2/E_2最低。同对发现中国人群的E_3/E_3表型百分分布明显高于西方人群,但未发现有E_2/E_2表型。我国人群Apo-E表型分布的这种特征可能与中国人群冠心病的患病率较西方人群为低有关。血清脂质测定和分析表明,具有不同表型人群的血脂水平无显著的统计学差异。  相似文献   

17.
The aim was to assess the in vitro effect of glycerol, ethylene glycol or acetamide on frozen-thawed ram spermatozoa. Aliquots of each sixteen ejaculates from four rams of the Morada Nova breed were diluted in Tris-egg yolk with glycerol (5%), ethylene glycol (3% or 5%) or acetamide (3% or 5%) and frozen at -196°C. After thawing, progressive sperm motility was greater (P<0.05) in cryopreservation with glycerol 5% and ethylene glycol (3% or 5%) than with acetamide (3% or 5%). Acrosome integrity was greater (P<0.05) with ethylene glycol 5% than acetamide (3% or 5%). The percentage of sperm without oxidative stress was greater (P<0.05) with ethylene glycol (3% or 5%) than with acetamide (3% or 5%). Plasma membrane integrity was greater with glycerol 5% (P<0.05) than with the other cryoprotectants. Thus, it is concluded that glycerol 5% and ethylene glycol 3% or 5% protect ram sperm against the harmful effects of freezing and that glycerol 5% offers greater protection to sperm plasma membrane.  相似文献   

18.
OBJECTIVES--To examine the relation between coronary heart disease and the apolipoprotein E phenotypes in patients with non-insulin dependent diabetes mellitus. DESIGN--Cross sectional study. SETTING--District around Kuopio University Central Hospital, East Finland. SUBJECTS--138 men with non-insulin dependent diabetes and 64 men without diabetes as controls. MAIN OUTCOME MEASURE--Apolipoprotein E phenotype, electrocardiographic abnormalities, other signs of coronary heart disease. RESULTS--The prevalences of definite myocardial infarction and ischaemic electrocardiographic changes were highest in the diabetic men with the phenotypes E4/4 or E4/3 (25% (95% confidence interval 18% to 32%) and 50% (42% to 58%) respectively), although the difference between the phenotype groups was not significant. The prevalence of angina pectoris was 69% (61% to 77%) in men with the phenotypes E4/4 or E4/3 (p = 0.005 compared with other phenotypes), 41% (33% to 49%) in men with phenotype E3/3, and 47% (39% to 55%) in those with phenotypes E2/2 or E2/3. Similarly, the simultaneous presence of angina pectoris and ischaemic electrocardiographic changes was highest in the diabetic men with the phenotypes E4/4 or E4/3 (42% v 22% in those with E3/3 and 29% in those with E2/2, E2/3; p = 0.038). Overall, the prevalence of any evidence of coronary heart disease among the diabetic subjects with the phenotypes E4/4 or E4/3 was 81% (p = 0.011 compared with other phenotypes), 58% in those with phenotype E3/3, and 53% in those with phenotypes E2/2 or E3/3. CONCLUSION--Apolipoprotein E phenotypes E4/4 and E4/3 modulate the risk of coronary heart disease in men with non-insulin dependent diabetes.  相似文献   

19.
Quantitative carotenoid analysis of a natural bloom of Euglena sanguinea Ehrenberg revealed the presence of β,β-carotene (1% of total carotenoids), monoesters of adonirubin (3%), diesters of (3S, 3′R)-adonixanthin (13%), diesters of (3S, 3′S)-astaxanthin (75%), 19-monoester of (3R, 3′R, 6R)-loroxanthin (1%), (3R, 3′R)-diatoxanthin (6%), diadinoxanthin (1%) and neoxanthin (traces). The carotenoid content amounted to 0.7% of the dry wt. Methods employed included TLC, HPLC, VIS, MS, CD and H NMR (400 and 500 MHz). The high content of ketocarotenoids is characteristic of secondary carotenoids produced under stressed growth conditions. Previously secondary carotenoids were associated with green algae (Chlorophyceae), but have now been encountered in Euglenophyceae.  相似文献   

20.
In an effort to explain the difference in potencies between the two characterized crustacean pigment-dispersing hormones (alpha-PDH; beta-PDH) and to define a role for residue 3 in these octadecapeptide hormones, we have synthesized and purified seven position 3 alpha-PDH analogues ([Ala3], [Ile3], [Asn3], [Gln3], [Asp3], [Glu3], and [Lys3]alpha-PDH). When tested for melanophore pigment-dispersing activity in destalked Uca, [Glu3]alpha-PDH was found to be 325% more potent than alpha-PDH. Reduced potencies were observed for the [Asp3] (58%), [Asn3] (26%), [Gln3] (11%), and [Ala3] (8%) derivatives. Much lower potencies were displayed by the [Lys3] and [Ile3] analogues (0.73% and 0.66%, respectively). These results suggest that the position 3 side chain carboxylate anion of [Glu3]alpha-PDH stabilizes the active receptor-bound conformer through a charge-charge interaction.  相似文献   

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