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1.
几种药用植物基因组DNA提取方法研究 总被引：3，自引：0，他引：3
采用改良2×CTAB法和改良SDS法提取富含多糖和次生代谢物质的几种药用植物不同器官基因组DNA,并用紫外分光光度计分析,凝胶电泳和PCR扩增进行鉴定。结果表明:改良2×CTAB法和改良SDS法均能有效去除不同药用植物材料中的蛋白质、多糖、酚类及其他次生代谢物质,获得较高质量基因组DNA。但与改良SDS法相比,改良2×CTAB法提取的基因组DNA质量更好。 相似文献
2.
文章用2XCTAB法、SDS法、一步法三种方法从含有大量多糖、酚类、醌类、萜等次生代谢产物的松科植物太白红杉中提取和纯化了基因组总DNA,并经0.6%琼脂糖凝胶电泳,紫外吸收值比值对所提DNA的产率、质量和纯度作了鉴定,为太白红杉的分子生物学研究、鉴定提供了可靠的基础。 相似文献
3.
郝阳 《浙江大学学报(A卷英文版)》2006,7(1):34-40
INTRODUCTION Electromagnetic crystal structures (ECSs) offer the opportunity to control and manipulate electro- magnetic wave propagation as a result of their being formed from small-scale periodic geometric struc- tures. This detailed microscopic configuration can be designed to cause the material (macroscopically) to exhibit either effective permittivity or permeability that is negative over a finite frequency range. This modifies the dispersion relation of electromagnetic waves and a … 相似文献
4.
Bogdan Munteanu Mario Braun Kajohn Boonrod 《Journal of Zhejiang University. Science. B》2012,13(4):244-247
QuickChange mutagenesis is the method of choice for site-directed mutagenesis (SDM) of target sequences in a plasmid. It can
be applied successfully to small plasmids (up to 10 kb). However, this method cannot efficiently mutate bigger plasmids. Using
KOD Hot Start polymerase in combination with high performance liquid chromatography (HPLC) purified primers, we were able
to achieve SDM in big plasmids (up to 16 kb) involving not only a single base change but also multiple base changes. Moreover,
only six polymerase chain reaction (PCR) cycles and 0.5 μl of polymerase (instead of 18 PCR cycles and 1.0 μl of enzyme in
the standard protocol) were sufficient for the reaction. 相似文献
5.
6.
针禾属植物羽毛针禾基因组DNA提取方法的研究 总被引：3，自引：0，他引：3
传统的CTAB DNA提取法步骤多.较烦琐,DNA产率低,而且由于酚、单宁、色素、多糖很难完全去除,容易影响随机扩增多态、微卫星等标记工作的效率.采用SDS裂解法提取了针禾属植物幼嫩叶片的基因组DNA,所获得的DNA可用于PCR反应.并且在针禾属植物的研究中得到了较好的结果. 相似文献
7.
Lead concentrations in roots, stems and leaves of accumulating and non-accumulating ecotypes ofSedum alfredii (Hance) were studied through a hydroponic experiment with different Pb concentrations supplied as Pb(NO3)2. Lead concentrations in leaves and stems of the accumulating ecotype were 4–9 times and 3–5 times those of the non-accumulating
ecotype, and Pb-accumulated amounts in stems and leaves of the accumulating ecotype were 4–9 times and 8–11 times higher than
those of the non-accumulating ecotype, respectively. The results indicated that the accumulating ecotype had better ability
to transport Pb from roots to shoots. The subcellular distributions of Pb in the root, stem and leaf tissues were studied
using sucrose differential centrifugation. Approximately 50% of Pb contents was found to be associated with the cell wall
fraction in stems of the accumulating ecotype and the percentage increased to 80% both in roots and leaves, no matter when
plants were grown with different levels of Pb. The results indicated that the distribution of Pb on cell walls of the accumulating
ecotype could mainly account for the high tolerance to Pb.
Project supported by a Key Project from the Educational Ministry of China (No:02180) and by the Outstanding Young Scientist
Grant from the National Natural Science Foundation of China (No: 39925024). 相似文献
8.
芒果皮活性成分的萃取及其生理活性研究 总被引：1，自引：0，他引：1
芒果皮中含有黄酮类、糖及苷类、酚类、有机酸和挥发油等多种活性成分.综述了芒果皮活性成分的萃取、生理活性研究现状及其应用前景.为芒果皮的进一步研究与开发提供参考. 相似文献
9.
Qi WANG Xiaoxia SHEN Tian QIU Wei WU Lin LI Zhi'an WANG Huixia SHOU 《Journal of Zhejiang University. Science. B》2021,22(2):99
Nucleic acids in plant tissue lysates can be captured quickly by a cellulose filter paper and prepared for amplification after a quick purification.In this study,a published filter paper strip method was modified by sticking the filter paper on a polyvinyl chloride resin(PVC)sheet.This modified method is named EZ-D,for EASY DNA extraction.Compared with the original cetyl trimethylammonium bromide(CTAB)method,DNA extracted by EZ-D is more efficient in polymerase chain reaction(PCR)amplification due to the more stable performance of the EZ-D stick.The EZ-D method is also faster,easier,and cheaper.PCR analyses showed that DNA extracted from several types of plant tissues by EZ-D was appropriate for specific identification of biological samples.A regular PCR reaction can detect the EZ-D-extracted DNA template at concentration as low as 0.1 ng/μL.Evaluation of the EZ-D showed that DNA extracts could be successfully amplified by PCR reaction for DNA fragments up to 3000 bp in length and up to 80%in GC content.EZ-D was successfully used for DNA extraction from a variety of plant species and plant tissues.Moreover,when EZ-D was combined with the loop-mediated isothermal amplification(LAMP)method,DNA identification of biological samples could be achieved without the need for specialized equipment.As an optimized DNA purification method,EZ-D shows great advantages in application and can be used widely in laboratories where equipment is limited and rapid results are required. 相似文献
10.
The clinical diagnosis of sepsis is difficult, particularly in neonates. To devise a rapid and reliable method for identifing
bacteria in blood and cerebrospinal fluid (CSF), we developed a pair of primers according to the gene encoding 16 s rRNA,
found in all bacteria. DNA fragments from different bacterial species and from clinical samples were detected with polymerase
chain reaction (PCR), and with reverse hybridization using a universal bacterial probe, a gram-positive probe and a gram-negative
probe. Our results showed that a 371 bp DNA fragment was amplified from 20 different bacterial species. No signal was observed
when human DNA and viruses were used as templates. The sensitivity could be improved to 10−12 g. All 26 culture-positive clinical samples (22 blood samples and 4 CSF samples), were positive with PCR. The gram-negative
and gram-positive probe hybridized to clinical samples and to known bacterial controls, as predicted by Gram’s stain characteristics.
Our results suggest that the method of PCR and reverse hybridization is rapid, sensitive and specific in detecting bacterial
infections. This finding may be significant in the clinical diagnosis of sepsis in neonates.
Project (396457) supported by the Zhejiang Provincal Natural Science Foundation. 相似文献
11.
Embryogenic calli were induced from the seeds of creeping bentgrass (Agrostis palustris Huds.) cv. Regent and colonial bentgrass (Agrostis Tenuis Sibth. Fl. Oxen.) cv. Tiger. The embryogenic calli were precultured on fresh medium for 4–7 days and then co-cultivated withAgrobacterium tumefaciens, LBA4404. which contains plasmid vector-pSBGM harboring bar coding region, synthetic green fluorescent protein (sGFP) coding
region and matrix attachment region (MAR). After 3 days of co-cultivation, the calli were washed thoroughly and transferred
to MS medium containing 2 mg/L of 2, 4-D, 12–15 mg/L phosphinothricin (PPT) and 250 mg/L of cefotaxime. After 2–3 months of
selection, the actively growing calli of ‘Regent’ and ‘Tiger’ were transferred to MS medium with 12–15 mg/L PPT and 250 mg/L
cefotazime for regeneration. The putative transformants were maintained on MS medium with 3 mg/L PPT for long period but control
died within 1 month. After establishing in greenhouse, the transformants also showed strong resistance to 0.4% of herbicide
Basta but control plants died within 2 weeks. Under confocal microscope, both young leaves and roots showed significant GFP
expression. PCR analysis revealed the presence of a DNA fragment of GFP gene at the expected size (380 bp) in the transformants
and its absence in a randomly selected control plant. 相似文献
12.
以蛇菰为材料,采用水提醇沉法提取浓缩后获得蛇菰多糖,以改良苯酚—硫酸比色法测定其多糖量.研究表明,蛇菰中多糖的质量分数为0.38%;加样回收率为100.73%,RSD为1.61%.因此,水提醇沉法可作为蛇菰中多糖的提取方法,改良苯酚—硫酸比色法可以作为蛇菰中多糖的定量测定方法. 相似文献
13.
Learning Using Dynamic and Static Visualizations: Students’ Comprehension, Prior Knowledge and Conceptual Status of a Biotechnological Method 总被引：1，自引：0，他引：1
The importance of biotechnology education at the high-school level has been recognized in a number of international curriculum
frameworks around the world. One of the most problematic issues in learning biotechnology has been found to be the biotechnological
methods involved. Here, we examine the unique contribution of an animation of the polymerase chain reaction (PCR) in promoting
conceptual learning of the biotechnological method among 12th-grade biology majors. All of the students learned about the
PCR using still images (n = 83) or the animation (n = 90). A significant advantage to the animation treatment was identified following learning. Students’ prior content knowledge
was found to be an important factor for students who learned PCR using still images, serving as an obstacle to learning the
PCR method in the case of low prior knowledge. Through analysing students’ discourse, using the framework of the conceptual
status analysis, we found that students who learned about PCR using still images faced difficulties in understanding some
mechanistic aspects of the method. On the other hand, using the animation gave the students an advantage in understanding
those aspects. 相似文献
14.
What makes a problem mathematically interesting? Inviting prospective teachers to pose better problems 总被引：1，自引：0，他引：1
School students of all ages, including those who subsequently become teachers, have limited experience posing their own mathematical
problems. Yet problem posing, both as an act of mathematical inquiry and of mathematics teaching, is part of the mathematics
education reform vision that seeks to promote mathematics as an worthy intellectual activity. In this study, the authors explored
the problem-posing behavior of elementary prospective teachers, which entailed analyzing the kinds of problems they posed
as a result of two interventions. The interventions were designed to probe the effects of (a) exploration of a mathematical
situation as a precursor to mathematical problem posing, and (b) development of aesthetic criteria to judge the mathematical
quality of the problems posed. Results show that both interventions led to improved problem posing and mathematically richer
understandings of what makes a problem ‘good.’ 相似文献
15.
Insulin is a major protein hormone secreted by the β-cells of the pancreas and is important for the control of diabetes. Insulin
is usually administered to diabetic patients through subcutaneous injection. This mode of therapy has certain inherent disadvantages
such as local pain, itching and insulin lipodystrophy around the injection site. Hence, pharmaceutical scientists have been
trying to design an oral delivery system for insulin. Many challenges are associated with the oral delivery of insulin, relating
to the physical and chemical stability of the hormone, and its absorption and metabolism in the human body. Here we discuss
various strategies for the oral delivery of insulin that are being tried out, as well as methods used to improve the absorption
of orally consumed insulin and to reduce its degradation by digestive enzymes.
K Gowthamarajan is on the faculty of the Department of Pharmaceutics in JSS College of Pharmacy, Ootacamund. His research
interests are in the area of designing drug delivery systems for peptides and proteins. He is currently involved in research
on pharmaceutical applications of plant polysaccharides.
Giriraj T Kulkarni is on the faculty of the Department of Pharmaceutics in JSS College of Pharmacy, Ootacamund. Currently,
he is involved in research on pharmaceutical and biotechnological applications of plant polysaccharides. He has authored a
book ‘Biotechnology and its Applications in Pharmacy’ for undergraduate and postgraduate students of pharmacy. 相似文献
16.
四种药用蕨类DNA提取的比较研究 总被引：3，自引：0，他引：3
以四种药用蕨类的叶片为材料,采用改进的CTAB法、SDS法分别对四种蕨类进行了总DNA提取效果的比较分析,结果表明,通过实验获得最佳的DNA提取方法,为PCR扩增,引物设计,为筛选四种药用蕨类中的活性成份的相关基因奠定理论和实践基础。两种方法均能有效的提取较高质量的DNA,其中CTAB法效果最好,获得的DNA纯度较高、产量较大;SDS法提取的量次之且多糖等杂质含量更多。 相似文献
17.
RAPD在蔬菜种子纯度鉴定中应用的反应条件优化 总被引：2，自引：0，他引：2
随着分子生物学的发展,ＲＡＰＤ（随扩增多态性ＤＮＡ）在越来越多的领域得到应用,但在蔬菜纯度鉴定方面,国内外报道较少,为了更好地将ＲＡＰＤ方法应用于蔬菜种子纯度鉴定,就反应条件进行了探索,以几种蔬菜种子为材料,使用进口ＰＣＲ仪在,对几种蔬菜种子进行ＲＡＰＤ分子过程中,从ＤＮＡ提取方法,模板ＤＮＡ量,Ｍｇ＾２＋浓度,Ｔａｑ－ＤＮＡ聚合酶的量,ｄＮＴＰｓ浓度,随机引物浓度及反应缓冲液的量等几个方面进行研 相似文献
18.
Important goals in science education include the elucidation of how students develop a world view, reason about new information,
and solve problems. This paper focuses on a research strategy using microcomputers that is directed towards elucidating conceptual
understanding and problem solving strategies used by subjects interacting with an open-ended genetics simulation. The field
method employed in this study is termed “structured observations”. The use of this method facilitated the generation of data
during problem solving sessions by subjects in a think aloud protocol. Three sets of synchronized information of subjects’
interactions with the software were obtained: a video image which provided the sequence and duration of computer screen displays,
a video image of subjects, and an audio track of verbal commentaries. The verbal protocol data, complemented by synchronized
visual data, were analyzed using software tools for qualitative analysis. The use of these kinds of software programs aided
researchers in the analysis of complex, qualitative data. The data were subjected to codings as text files, searches for patterns,
and retrievals of patterns among coded variables. Frequency tables of the codes and patterns were generated for further interpretation.
By these means, patterns of operations can be identified and inferences made about problem solvers’ conceptual understanding.
Specializations: computer-based problem solving secondary teacher education.
Specializations: computer-based problem solving, software design and development. 相似文献
19.
Di JZ Han XD Gu WY Wang Y Zheng Q Zhang P Wu HM Zhu ZZ 《Journal of Zhejiang University. Science. B》2011,12(10):805-811
Global DNA hypomethylation has been associated with increased risk for cancers of the colorectum, bladder, breast, head and
neck, and testicular germ cells. The aim of this study was to examine whether global hypomethylation in blood leukocyte DNA
is associated with the risk of hepatocellular carcinoma (HCC). A total of 315 HCC cases and 356 age-, sex- and HBsAg status-matched
controls were included. Global methylation in blood leukocyte DNA was estimated by analyzing long interspersed element-1 (LINE-1)
repeats using bisulfite-polymerase chain reaction (PCR) and pyrosequencing. We observed that the median methylation level
in HCC cases (percentage of 5-methylcytosine (5mC)=77.7%) was significantly lower than that in controls (79.5% 5mC) (P=0.004, Wilcoxon rank-sum test). The odds ratios (ORs) of HCC for individuals in the third, second, and first (lowest) quartiles
of LINE-1 methylation were 1.1 (95% confidence interval (CI) 0.7–1.8), 1.4 (95% CI 0.8–2.2), and 2.6 (95% CI 1.7–4.1) (P for trend <0.001), respectively, compared to individuals in the fourth (highest) quartile. A 1.9-fold (95% CI 1.4–2.6) increased
risk of HCC was observed among individuals with LINE-1 methylation below the median compared to individuals with higher (>median)
LINE-1 methylation. Our results demonstrate for the first time that individuals with global hypomethylation measured in LINE-1
repeats in blood leukocyte DNA have an increased risk for HCC. Our data provide the evidence that global hypomethylation detected
in the easily obtainable DNA source of blood leukocytes may help identify individuals at risk of HCC. 相似文献
20.
目的:建立刺五加叶中5个酚类成分同时测定的一测多评法,为科学评价刺五加叶质量提供参考。方法:采用Agilent Elipse Plus C 18色谱柱(250 mm×4.6 mm,5μm),0.3%磷酸水-乙腈溶液梯度洗脱,流速1.0 mL/min,检测波长360 nm,柱温30℃。以绿原酸为内参物,计算新绿原酸、隐绿原酸、金丝桃苷、槲皮苷的相对校正因子(RCF),建立同时测定5种化合物含量的一测多评法。将一测多评法与外标法比较,考察一测多评法的准确度。结果:刺五加叶经HPLC检测,各目标成分分离度良好,方法学考察符合要求。以绿原酸为内参物,计算得出新绿原酸、隐绿原酸、金丝桃苷、槲皮苷的相对校正因子分别为0.906、0.899、3.136、2.645。与外标法比较无显著差异。结论:建立的一测多评法简单、准确,适用于刺五加叶中5种成分含量的同时测定,可为提高刺五加叶质量标准提供依据。 相似文献