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排序方式: 共有315条查询结果,搜索用时 31 毫秒
151.
本文主要对锦带花乙酸乙酯提取物化学成分进行研究。采用醇提法提取锦带花中的化学成分,并依次用石油醚、乙酸乙酯、正丁醇萃取,通过柱色谱,薄层制备色谱,凝胶柱色谱及重结晶等方法对乙酸乙酯提取物进行分离纯化。得到5个化合物,分别鉴定为:槲皮素(quercetin,I),原儿茶酸(protocatechuic,II),莨菪亭(Scopoletin,III),6-甲氧基-7-氧代异戊烯基香豆素(6-methoxy-7-oxo isopentenyl coumarin,IV),β-谷甾醇(β-sitosterol,V),以上化合物均首次从该种植物得到。 相似文献
152.
文章研究了KBT—ZTC絮凝剂对合欢皮总多糖的絮凝纯化工艺,通过单因素和正交实验,得到优化的工艺条件:KBT—ZTC的A、B组分质量体积比为各0.40mL/g,絮凝温度35℃,絮凝时间2h,药液浓缩比1:10,得到多糖保留率、脱蛋白率和纯度分别为90.81%、52.89%和49.65%,均高于水提醇沉工艺的纯化效果. 相似文献
153.
家具中甲醛污染具有持续性,通常是持续10~15年,对人体健康产生很大的影响。本文选取了市面上销售的一种含甲壳素除甲醛试剂,通过实验确定了甲壳素对家具中甲醛的净化效率,同时对其净化机理进行了简单分析,为后续研究甲壳素除甲醛的持续性效果研究打下了基础。 相似文献
154.
相平衡理论是选择分离方法、设计分离装置以及实现最佳操作的理论基础.在化工分离提纯时,相平衡原理的应用主要体现在:对单组分系统可采用超临界萃取方式,对二组分液态完全互溶系统的气液平衡可采用蒸馏和精馏的方法,对二组分液态完全不互溶系统的气液平衡可采用蒸汽蒸馏的方式,对二组分固态完全互溶系统可采用区域熔炼法. 相似文献
155.
Yousef Rezaei Chianeh Rashmi Manjunath Krishnananda Prabhu Donald Fernandes M. Vidyasagar Asha Kamath 《Indian journal of clinical biochemistry : IJCB》2014,29(2):238-241
Oral squamous cell carcinoma is one of the most common malignancies recognized. Biomarkers which can predict presence of cancer and its progression can help in better management of these disorders. Over production of lipid peroxidation byproducts and disturbances in antioxidant defense system have been implicated in the pathogenesis of several diseases including oral cancer. Studies have shown a correlation of butyrylcholinesterase (BChE), with tumourigenesis, cell proliferation and cell differentiation. Earlier we have observed a significant elevation in plasma BChE and protein thiols in oral cancer patients which correlated well with stages of cancer. As it was not clear whether the above markers will be altered in saliva of oral cancer patients this study was undertaken. Institutional Ethics Committee gave permission to carry out this study. Total of 55 subjects comprising healthy controls (n = 30) and biopsy proven oral cancer patients (n = 25) consented to participate in this study. Salivary samples from cases were taken before any definitive treatment. Protein thiols and BChE were estimated in salivary samples using validated assay methods. Oral cancer patients had a significant increase in pre-treatment salivary BChE levels (p ≤ 0.001) and a significant decrease (p ≤ 0.001) in salivary thiols as compared to respective values in controls. Salivary protein thiols and BChE may have a role in pathophysiology of oral cancer. Saliva can be used as a potential non-invasive screening tool in oral cancer patients. 相似文献
156.
目的:以白桦树皮为原料,研究了白桦树皮中白桦脂醇提取和纯化的工艺,并使此工艺适合药用放大生产。方法:使用乙醇提取,使用乙酸乙酯和不同浓度的乙醇进行精制。结果:所得到的精制品经过高效液相检验含量在98%以上。结论:白桦脂醇的提取纯化过程中使用的都是常规的可操作方法,适合放大生产。 相似文献
157.
为纯化紫苏籽油中的α-亚麻酸,将传统的低温冷冻结晶法和尿素包合法有机结合,对纯化工艺进行优化.结果表明:紫苏籽油在y(无水乙醇):V(丙酮)=1:1混合溶剂,粗品:尿素:混合溶剂=2:1:10,冷藏时间为36h时,析出的晶体最长、用时最短.采用筛选的溶剂和优化的工艺条件可大大提高晶体析出量、缩短晶体的析出时间,使纯化后紫苏籽油中的α-亚麻酸从原来的304mg/mL提高到644mg/mL. 相似文献
158.
Bharosay A Saxena K Varma M Bharosay VV Pandey A 《Indian journal of clinical biochemistry : IJCB》2011,26(3):279-282
Stroke being the third leading cause of death and foremost cause of disability, if potential diagnostic utility of blood borne
protein biomarkers in predicting acute stroke is established, it would be a substantial adjunct to computerized tomography
and magnetic resonance imaging which have their own limitations. This study was done to correlate serum Interleukin 6, high
sensitivity C reactive protein at the time of admission with neurological worsening assessed by NIHSS at the time of admission
and 7 days after admission. 46 Patients admitted in neurology department SAIMS, Indore with first ever ischemic stroke within
72 h of onset were included in the study. All patients with history of stroke of more than 72 h onset, Infection & peripartum
stroke were excluded from the study. Disability scoring was done by NIHSS and their serum samples assayed for hsCRP, IL6 by
commercially available quantitative sandwich enzyme-linked immunoadsorbent assay kits. Serum samples of 50 control cases which
included healthy volunteers and staff from SAIMS were also analyzed for hsCRP, IL6 for comparative study. A significant correlation
was observed between NIHSS scoring and serum hsCRP and IL6 at the time of admission. Patients with initial high serum IL6
and hsCRP also showed significant clinical deterioration as assessed by NIHSS scoring 7 days after admission. Elevated hsCRP
and IL6 within 72 h of admission strongly correlated with functional disability in study population in India and may serve
as useful adjunct to CT Scan in emergency setting. 相似文献
159.
Kritsanee Maneewong Titiporn Mekrungruangwong Saowanee Luangaram Tomon Thongsri Sarawut Kumphune 《Indian journal of clinical biochemistry : IJCB》2011,26(4):389-395
Ischemia modified albumin (IMA) and Protein Carbonyl (PC) have known as proteins that are modified on the similar basis of
oxidative stress induced protein modification and may have diagnostic potential in acute myocardial infarction. This study
aims to evaluate the ability of using IMA and PC content to diagnose Non-ST elevation myocardial infarction (NSTEMI) and efficiency
of combining these two markers. Serum from NSTEMI and healthy control were determined for serum IMA and PC content. The results
showed that both of serum IMA level and PC content in NSTEMI was significantly higher than that of healthy controls. However,
the PC content showed greater diagnostic performance than IMA. Combinatorial determination of serum IMA level with PC content
level was enhanced test efficiency. In conclusion, our finding demonstrated that IMA and PC content can be used as a diagnostic
marker for NSTEMI. 相似文献
160.
Kang Wei Da-wei Xue You-zong Huang Xiao-li Jin Fei-bo Wu Guo-ping Zhang 《Journal of Zhejiang University. Science. B》2009,10(11):839-846
High malting quality of barley (Hordeum vulgate L.) relies on many traits, such as β-amylase and limit dextrinase activities and β-glucan and protein fraction contents. In this study, interval mapping was utilized to detect quantitative trait loci (QTLs) affecting these malting quality parameters using a doubled haploid (DH) population from a cross of CM72 (six-rowed) by Gairdner (two-rowed) barley cultivars. A total of nine QTLs for eight traits were mapped to chromosomes 3H, 4H, 5H, and 7H. Five of the nine QTLs mapped to chromosome 3H, indicating a possible role of loci on chromosome 3H on malting quality. The phenotypic variation accounted by individual QTL ranged from 8.08% to 30.25%. The loci of QTLs for β-glucan and limit dex-trinase were identified on chromosomes 4H and 5H, respectively. QTL for hordeins was coincident with the region of silica eluate (SE) protein on 3HS, while QTLs for albumins, globulins, and total protein exhibited overlapping. One locus on chromosome 3H was found to be related to β-amylase, and two loci on chromosomes 5H and 7H were found to be associated with glutelins. The identification of these novel QTLs controlling malting quality may be useful for marker-assisted selection in improving barley malting quality. 相似文献