透明质酸的离子交换层析纯化

采用强酸型阳离子树脂为交换剂的离子交换柱,和经组氨酸基团修饰的强碱型阴离子树脂为交换剂的离子交换层析柱串联,以氯化钠溶液为洗脱剂,对透明质酸粗品进行分离和纯化.得到的透明质酸精品的蛋白质含量低于0.075%,平均分子量大于9.41×105,纯化收率为58%～61%.并对洗脱剂的流速、浓度、pH等条件进行比较,确定了最佳洗脱条件.     

离子交换层析法分离纯化玻璃酸的研究

选用四种离子交换剂对玻璃酸进行分离纯化研究。结果表明，采用D315大孔离子交换剂，以去离子水为淋洗液、0．6mol／LNaCl溶液为洗脱液，纯化效果较佳。纯化产品杂蛋白含量≤0．3％，粘均分子量＞96×104。     

离子交换树脂在口服液体制剂矫味中的应用

改善口感和掩盖苦味是口服液体制剂的一个重要研究课题。离子交换树脂是一类能进行离子交换的功能性高分子聚合物,与药物结合形成药物树脂复合物之后,可以改善或屏蔽药物的苦味。国内外已上市的多种产品使用了离子交换树脂作为药用矫味剂。文中简要介绍了离子交换树脂的种类、基本性质、作用原理以及在口服液体制剂矫味中的作用机制、独特优势和应用研究进展。     

以强阴离子交换剂FG TMAE 为介质的离子交换层析制备人凝血因子Ⅷ的初探

目的  初步探索以强阴离子交换剂FG TMAE为介质进行离子交换层析来制备人凝血因子Ⅷ。方法  以含不同氯化钠浓度的洗脱液进行线性梯度来初步确定离子交换层析的条件,并优化离子交换层析的洗涤液和洗脱液的离子强度和pH值以及样品的温度,最终确定以强阴离子交换剂FG TMAE为介质进行离子交换层析的最适条件。结果  在室温（20~25 ℃）条件下,以pH 7.0的含220 mmol/L氯化钠的洗涤液和pH 7.0的含450 mmol/L氯化钠的洗脱液进行离子交换层析,可使人凝血因子Ⅷ 的回收率（77.53%）和比活性（24.67 IU/mg）均较高。结论  以强阴离子交换剂FG TMAE为介质进行离子交换层析制备人凝血因子Ⅷ 是可行的。     

离子交换树脂处理方法的改进

目的：改进离子交换树脂处理方法，提高处理效果，减少对环境的污染及资源的浪费。方法：采用改进的离子交换柱体对离子交换树脂进行单独处理。结果：离子交换树脂的处理效果符合要求。结论：改进法可行。     

吸附与离子交换及其在生物技术上的应用

阐述了吸附与离子交换过程的基本概念、理论基础、应用方式及范围和天然与合成的吸附剂与离子交换剂等，特别介绍了近年发展起来的疏水作用吸附、盐析吸附、亲和吸附、染料配位体吸附、免疫吸附和羟基磷灰石吸附、磷酸钙凝胶吸附等的机理及其在生物技术上的应用。     

利用离子交换法提取L-异亮氨酸的研究

利用离子交换法从Ｌ 异亮氨酸发酵液中分离提取Ｌ 异亮氨酸．考察了发酵液酸化ｐＨ值，不同浓度洗脱剂以及单柱与双柱串连吸附对Ｌ 异亮氨酸分离提取的影响．确定了发酵液酸化ｐＨ低于２５，双柱串连吸咐，用０２ｍｏｌ·Ｌ－１ＮＨ４Ｃｌ ０１ｍｏｌ·Ｌ－１ＮＨ４ＯＨ复合洗脱剂洗脱的分离效果较好．提取总收率可达４５％以上．     

离子交换纤维纯化绿原酸的研究

目的对金银花中绿原酸的提取工艺进行研究.方法以乙醇为溶剂,采用动态吸附实验考察优化的吸附-解吸条件.结果离子交换纤维提取绿原酸的优化工艺条件为:吸附时间60min,流速4·0ml?min-1,解吸时以甲醇-盐酸(1mol?L-1)=4∶1混合溶液作为解吸剂,流速为0·8ml?min-1.结论离子交换纤维应用于绿原酸的提取中效果好,适宜于产业化生产.     

控制电渗析器脱盐率延长离子交换树脂使用周期

目的 使电渗析器和离子交换树脂在制备去离子水时实现自动化、半自动化的控制要求。方法 对DSX-03型电渗析器脱盐率t(％)和JHZ型离子交换树脂使用周期D(d)之间的关系进行考察。结果 在一定的脱盐率范围内，两者线性相关r=0．9990(n=5)。结论 控制电渗析器脱盐率，能够延长离子交换树脂的使用周期，降低注射用水的生产成本。     

离子交换纤维对葛根素静态吸附和解吸作用的考察

目的考察离子交换纤维对葛根素的静态吸附和解吸作用。方法将离子交换纤维预处理并制得饱和吸附纤维后,分别考察温度、pH值对葛根素静态吸附和解吸的影响,由此确定离子交换纤维提取纯化葛根素的影响因素和程度。结果离子交换纤维的吸附量和解吸量与葛根素溶液的温度、pH值和相互作用时间有关,作用时间越长、pH值越大,吸附量则越大;在pH值为9、作用时间为40 min时,最佳吸附温度为70℃;在一定的pH值条件下,用乙醇可以将吸附在离子交换纤维上的葛根素迅速解吸下来;最佳的醋酸解吸剂的浓度为2 mol.L-1,最佳静态解吸温度控制在40~60℃。结论用离子交换纤维提取纯化溶解在乙醇中的葛根素的方法是可行的;本方法为葛根素的分离提纯开辟了新的途径,奠定了新的基础,对中药标准化生产具有重要意义。     

Effect of a contraceptive steroid combination of the "serum activation" of lipoprotein lipase in rats.

Our investigation on serum obtained from control rats and from rats treated with a steroid contraceptive drug (SCD) showed that serum from SCD treated rats had a lower activating capacity for lipoprotein lipase from rat epididymal adipose tissue. A similar result was observed when HDL apolipoproteins obtained from serum of these two groups of rats were tested against a lipoprotein lipase preparation. The data suggest a deficiency or an alteration of some serum cofactors (probably apolipoproteins of the C group). The observation that chylomicrons from SCD treated rats were slightly poorer substrate for lipoprotein lipase than those from control rats supports the hypothesis of a cofactor deficiency rather than a transfer of apolipoproteins from HDL to chylomicrons.     

Aporphine Alkaloids of Ocotea brenesii

The aporphine alkaloids (+)-isocorydine, (-)-3-hydroxynuciferine, and 3-hydroxy-6a,7-dehydronuciferine were isolated from the alkaloid fraction of an ethanol extract of the leaves of Ocotea brenesii Standley. Although (+)-isocorydine has been isolated from extracts of several Ocotea species previously, this is the first reported isolation of (-)-3-hydroxynuciferine and 3-hydroxy-6a,7-dehydronuciferine from this genus. Finally, to our knowledge, this is the first reported isolation of (-)-3-hydroxynuciferine from nature, although the compound was previously synthesized from nuciferine. In addition, it is only the second reported isolation of 3-hydroxy-6a,7-dehydronuciferine from a higher plant.     

不同职业入伍的新兵社会状况及心理素质的研究

目的 研究不同职业入伍新兵的社会状况和心理素质特点.方法 整群抽取某部2630名集训新兵进行社会状况分析,并应用症状自评量表(SCL-90)、艾森克成人个性问卷(EPQ)、自我和谐量表(SCCS)、简易应对方式问卷(CSQ)、社会支持量表(SSRS)进行心理调查.结果 收回有效问卷2599份,城镇入伍、双亲家庭、高中以上文化、主动入伍、要求进步的新兵中入伍前职业是学生者较多;农村入伍、单亲家庭、初中以下文化、被动入伍的新兵中其他职业入伍者较多(P<0.05).SCL-90:学生新兵强迫、人际关系敏感、抑郁、焦虑、敌对、精神病性因子得分低于其他职业新兵(P<0.05,P<0.01);EPQ:学生新兵内外向因子得分高于其他职业新兵,而神经质和精神质得分低于其他职业新兵(P<0.01);SCCS:学生新兵自我不和谐、自我刻板性因子得分低于其他职业新兵,而自我灵活性得分高于其他职业新兵(P<0.01);CSQ:学生新兵积极应对得分高于其他职业新兵(P<0.01);学生新兵SSRS各因子得分均高于其他职业新兵(P<0.01).结论 学生新兵心理素质较好,可塑性强,入伍前职业是影响新兵心理素质的重要因素之一;新兵入伍后应结合入伍动机、目的、家庭状况,从自我和谐、积极应对、主动寻求支持等方面加强新兵的个性塑造.     

Do Sources of Cigarettes Among Adolescents Vary by Age Over Time?

Trends in sources of cigarettes among adolescents were assessed using data from a teen cohort (2000–2006). Five sources—bought from store, got from other teen, stole from others, bought from others, and got from an adult—were measured over time by age. The most common source among all ages was other teens. Fewer teens bought cigarettes from stores, with a downward trend for all ages. Among all ages there was an upward trend in stealing, with younger teens more likely to steal cigarettes. In addition to targeting cigarette sales, interventions are needed to target other youth cigarette sources.     

A quantitative ultrastructural comparison of macrophages from rats exposed to smoke derived from conventional tobacco and a tobacco substitute

Using an image analysing computer a variety of ultrastructural features from micrographs of alveolar macrophages have been quantified.Macrophages from rats exposed to smoke from conventional tobacco cigarettes, for 6 months, revealed statistically significant changes when compared to controls. The macrophages were larger, rounded with fewer pseudopodia and contained increased numbers of inclusions.There were no statistically significant changes in macrophages from rats exposed to smoke from a tobacco substitute.     

Estimating safe human exposure levels for lunar dust using benchmark dose modeling of data from inhalation studies in rats

Abstract

The pulmonary toxicity of airborne lunar dust was assessed in rats exposed by nose-only inhalation to 0, 2.1, 6.8, 20.8 and 60.6?mg/m3 of respirable size lunar dust. Rats were exposed for 6?h/d, 5?d/week, for 4 weeks (120?h). Biomarkers of toxicity were assessed in bronchial alveolar lavage fluid (BALF) collected at 1?d, 1 week, 4 weeks or 13 weeks post-exposure for a total of 76 endpoints. Benchmark dose (BMD) analysis was conducted on endpoints that appeared to be sensitive to dose. The number of endpoints that met criteria for modeling was 30. This number was composed of 13 endpoints that produced data suitable for parametric analysis and 17 that produced non-normal data. Mean BMD values determined from models generated from non-normal data were lower but not significantly different from the mean BMD of models derived from normally distributed data. Thus BMDs ranged from a minimum of 10.4 (using the average BMD from all 30 modeled endpoints) to a maximum of 16.6 (using the average BMD from the most restricted set of models). This range of BMDs yields safe exposure estimate (SEE) values of 0.6 and 0.9?mg/m3, respectively, when BMDs are extrapolated to humans, using a species factor of 3 and extrapolated from a 1-month exposure to an anticipated 6-month lunar surface exposure. This estimate is very similar to a no-observable-adverse-effect-level (NOAEL) determined from the same studies (0.4?mg/m3) and a SEE derived from a study of rats that were intratracheally instilled with lunar dusts (0.5–1.0?mg/m3).     

REDUCED RESPONSES TO NORADRENALINE OF ISOLATED DIGITAL ARTERIES FROM HYPERTENSIVES

1. Strips of digital arteries obtained post-mortem from thirteen hypertensives have been compared with those from thirteen normotensives. 2. The strips from hypertensives and from males had a significantly greater response to 80 mmol/1 KCl, but this was due to the increased cross-sectional areas of the strips from hypertensives and from males. 3. The maximum responses to noradrenaline and serotonin, but not the pED₅₀ values, were significantly smaller in the strips from the hypertensives than in those from the normotensives, but there were no differences between the strips from hypertensives and normotensives in either the maximum response or pED₅₀ values to angiotensin or barium chloride. 4. It is concluded that these results suggest a decreased number of α-receptors are present in human hypertensive vascular smooth muscle and this is a sequel either of the increased pressure itself, or of increased exposure in vivo of the blood vessels from hypertensives to noradrenaline.     

An improved method for the preparation of human fetal and adult hepatocytes

A method to prepare isolated hepatocytes from the small amounts of liver or liver fragments obtained from the human fetus following therapeutic abortion in early pregnancy is described. The hepatocytes have been characterized by electron microscopy and by their ability to dealkylatethe benzodiazepine drug prazepam.The preparation of hepatocytes from a liver sample obtained from a kidney transplant donor is described and discussed.     

Discovery of Small Molecule RIP1 Kinase Inhibitors for the Treatment of Pathologies Associated with Necroptosis

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