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991.
Cortisol is involved in the distribution and deposition of fat, and its action is regulated by the activity of 11beta-hydroxysteroid dehydrogenase. Glycyrrhetinic acid, the active principle of licorice root, blocks 11beta-hydroxysteroid dehydrogenase type 1, thus reducing the availability of cortisol at the level of adipocytes. We evaluated the effect of topical application of a cream containing glycyrrhetinic acid in the thickness of fat at the level of the thigh. Eighteen healthy women (age range 20-33 years) with normal BMI were randomly allocated to treatment, at the level of the dominant thigh, with a cream containing 2.5% glycyrrhetinic acid (n=9) or with a placebo cream containing the excipients alone (n=9). Before and after 1 month of treatment both the circumference and the thickness of the superficial fat layer of the thighs (by ultrasound analysis) were measured. The circumference and the thickness of the superficial fat layer were significantly reduced in comparison to the controlateral untreated thigh and to control subjects treated with the placebo cream. No changes were observed in blood pressure, plasma renin activity, plasma aldosterone or cortisol. The effect of glycyrrhetinic acid on the thickness of subcutaneous fat was likely related to a block of 11beta-hydroxysteroid dehydrogenase type 1 at the level of fat cells; therefore, glycyrrhetinic acid could be effectively used in the reduction of unwanted local fat accumulation.  相似文献   
992.
Over the years novel plant peroxidases have been isolated from palm trees leaves. Some molecular and catalytic properties of palm peroxidases have been studied. The substrate specificity of palm peroxidases is distinct from the specificity of other plant peroxidases. Palm peroxidases show extremely high stability under acidic and alkaline conditions and high thermal stability. Moreover, these enzymes are more stable with respect to hydrogen peroxide treatment than other peroxidases. Due to their extremely high stability, palm peroxidases have been used successfully in the development of new bioanalytical tests, the construction of improved biosensors, and in polymer synthesis.  相似文献   
993.
《Inorganica chimica acta》2004,357(10):3119-3123
Fused double-cluster [(η5-C5Me5)IrB18H18(PH2Ph)] (8), from syn-[(η5-C5Me5)IrB18H20] (1) and PH2Ph, retains the three-atoms-in-common cluster fusion intimacy of 1, in contrast to [(η5-C5Me5)HIrB18H19(PHPh2)] (6), from PHPh2 with 1, which exhibits an opening to a two atoms-in-common cluster fusion intimacy. Compound 8 forms via spontaneous dihydrogen loss from its precursor [(η5-C5Me5)HIrB18H19(PH2Ph)] (7), which has two-atoms-in-common cluster-fusion intimacy and is structurally analogous to 6.  相似文献   
994.
目的:探讨穴位敷贴法联合盐酸羟考酮缓释片对中重度癌性疼痛患者负性情绪及生活质量的影响。方法:选取2015年6月-2017年10月期间海南省人民医院收治的恶性肿瘤患者90例为研究对象。根据随机数字表法将患者分为对照组(n=45)与研究组(n=45),对照组患者给予盐酸羟考酮缓释片治疗,研究组患者在此基础上联合使用穴位敷贴法治疗。观察两组患者治疗后疼痛缓解情况及不良反应发生情况,比较两组患者治疗前后抑郁自评量表(SDS)评分、焦虑自评量表(SAS)评分以及生活质量情况。结果:研究组患者疼痛缓解率为66.67%(30/45),高于对照组的48.89%(22/45)(P0.05)。两组患者治疗后SDS评分、SAS评分均较治疗前降低,且研究组低于对照组(P0.05)。两组患者治疗后睡眠、饮食、日常生活以及情绪等评分均较治疗前降低,且研究组低于对照组(P0.05)。研究组患者恶心、头晕、排尿困难、便秘等发生率均低于对照组,差异有统计学意义(P0.05),而研究组皮肤刺激发生率与对照组相比差异无统计学意义(P0.05)。结论:穴位敷贴法联合盐酸羟考酮缓释片治疗可减轻中重度癌性疼痛患者疼痛程度,改善其负性情绪及生活质量,且不良反应较少。  相似文献   
995.
本文对2008—2017年申请国家自然科学基金及获得资助的医学病原微生物与感染科学领域肝炎病毒相关项目进行回顾分析,介绍面上项目、青年科学基金和地区科学基金项目的申请数量、资助项目数量及资助强度,并对医学病原微生物与感染科学领域肝炎病毒相关项目的特点及存在的问题进行分析。  相似文献   
996.
菌渣化肥配施对稻田土壤微生物量碳氮和可溶性碳氮的影响   总被引:12,自引:0,他引:12  
石思博  王旭东  叶正钱  陈绩  龚臣  李婷  任泽涛 《生态学报》2018,38(23):8612-8620
菌渣作为一种养分丰富的有机物料还田,可减少化肥施用,同时保持土壤肥力;而土壤微生物量碳、氮和可溶性碳、氮是土壤活性碳氮库的重要组成部分,其含量和比例变化对土壤肥力均具有重要作用。因此,探讨不同比例菌渣化肥配施对土壤微生物量碳、氮及可溶性碳、氮的影响,评价菌渣在优化土壤肥力方面的生态作用具有重要意义。本研究在水稻田间定位试验条件下,设置3个化肥水平(C) 0%、50%、100%,菌渣相对用量(F) 0%、50%、100%,共9个处理,分析了各处理土壤微生物量碳(MBC)、氮(MBN)和可溶性碳(DOC)、氮(DON)的变化特征,及其占土壤有机碳(SOC)和全氮(TN)的比例与相关关系。结果表明:菌渣化肥配施后,微生物量碳和可溶性碳、氮均在C100F50最高,微生物量氮在C50F100最高,与不施肥处理相比,分别显著增加了49.40%、43.65%、83.52%、207.19%;MBC/SOC和DOC/SOC均随着菌渣化肥配施量的增加而减少,MBN/TN和DON/TN均在C100F50最高。相关分析表明,MBC、DOC与SOC,MBN与TN均呈极显著正相关,DON和TN呈显著正相关。总体来讲,菌渣化肥配施能够显著提高土壤微生物量碳、氮和可溶性碳、氮含量,但不是随着用量的增加一直呈增加趋势,高量菌渣或者化肥下会有降低趋势;菌渣化肥配施降低了土壤微生物量和可溶性碳氮比,因此适宜的菌渣化肥配施是提高土壤有机碳周转速度、微生物活性及其氮素供应能力和有效性的最佳选择。  相似文献   
997.
Naturally occurring baculoviruses can be used to control a wide range of insect pests. Most baculoviruses are used as biopesticides, that is, they are sprayed onto high-density pest populations in a manner akin to the use of synthetic chemical pesticides. However, other strategies that use the biological features of the viruses are also possible and should increase as we expand our knowledge of baculovirus ecology. In order to develop a baculovirus control program, several areas need to be studied before progressing to large scale field studies and commercialization. These range from laboratory efficacy testing and the development of production systems to detailed study of pest behavior and the development of appropriate application strategies.  相似文献   
998.
Brassinosteroids have been reported to accelerate plant growth when applied to seeds. We examined the effects of seed treatment with brassinolide on early growth of Lepidium sativum (cress). Submicromolar and micromolar concentrations of brassinolide inhibited root growth within 48 h after seed treatment. Germination of cress was not affected by brassinolide. The inhibition of cress root growth by brassinolide was time specific in terms of eliciting the response. Untreated germinated seeds transferred to filter paper moistened with brassinolide solution did not exhibit the same level of root inhibition as treated seeds. Brassinolide (2 m) had no effect on ethylene levels, suggesting that at this concentration brassinolide is acting independently of ethylene to inhibit cress root elongation. Also, brassinolide had no effect on DNA synthesis within 24 h after seed treatment, but synthesis was reduced after 48 h. The results of this study illustrate a significant specific effect on very early cress root growth by seed treatment with brassinolide.Abbreviations BR brassinosteroid(s) - SDS sodium dodecyl sulfate - TCA trichloroacetic acid - ACC 1-aminocyclopropane-1-carboxylic acid  相似文献   
999.
1000.
Platinum colloids prepared by the reduction of hexachloroplatinic acid with citrate in the presence of different stabilizers were found to enhance the chemiluminescence (CL) of the luminol-H(2)O(2) system, and the most intensive CL signals were obtained with citrate-protected Pt colloids synthesized with citrate as both a reductant and a stabilizer. Light emission was intense and reproducible. Transmission electron microscopy and X-ray photoelectron spectroscopy studies were conducted before and after the CL reaction to investigate the possible CL enhancement mechanism. It is suggested that this CL enhancement is attributed to the catalysis of platinum nanoparticles, which could accelerate the electron-transfer process and facilitate the CL radical generation in aqueous solution. The effects of Pt colloids prepared by the hydroborate reduction were also investigated. The application of the luminol-H(2)O(2)-Pt colloids system was exploited for the determination of compounds such as uric acid, ascorbic acid, phenols and amino acids.  相似文献   
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