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151.
Lai CS Mas RH Nair NK Majid MI Mansor SM Navaratnam V 《Journal of ethnopharmacology》2008,118(1):14-20
AIM OF THE STUDY: Typhonium flagelliforme (Lodd.) Blume (Araceae) is a Malaysian plant used locally to combat cancer. In order to evaluate its antiproliferative activity in vitro and to possibly identify the active chemical constituents, a bioactivity guided study was conducted on the extracts of this plant. MATERIALS AND METHODS: The active extracts of Typhonium flagelliforme were fractionated by flash column chromatography and each fraction was evaluated for antiproliferative activity using MTT assay. The apoptotic effect of the active fraction was determined microscopically and by using TUNEL colorimetric assay. GC-MS and NMR were used to determine the chemical constituents of this active fraction. RESULTS: Several fractions of the hexane and dichloromethane extracts were found to inhibit the growth of NCI-H23 non-small cell lung carcinoma cell line significantly, with IC(50)<15 microg/ml. However, most of these active fractions were also found to inhibit the growth of non-tumorigenic BALB/c 3T3 mouse fibroblast cell line except for fraction 21 of the dichloromethane extract (D/F21). This particular fraction was not only less cytotoxic to the non-tumorigenic cells, where the IC(50) was 48.6 microg/ml compared to IC(50) 7.5 microg/ml for NCI-H23, but it was also found to induce apoptosis in the cancer cell line. GC-MS analysis revealed that D/F21 contains hexadecanoic acid, 1-hexadecene, phytol and a derivative of phytol. The presence of non-saturated fatty acids in this fraction was confirmed by nuclear magnetic resonance spectroscopy. CONCLUSIONS: D/F21 was found to be the active and cancer cell line specific fraction of Typhonium flagelliforme. Its major chemical constituents had been determined spectroscopically. 相似文献
152.
Sutherlandia frutescens (tribe Galegeae, Fabaceae), a popular plant in traditional medicine, is indigenous to South Africa, Lesotho, southern Namibia and southeastern Botswana. It is chemically, genetically and geographically extremely variable and has been divided into three subspecies and several regional forms. A second species, Sutherlandia tomentosa, is localized along the Cape coast. Sutherlandia is sometimes treated as part of the genus Lessertia. There are numerous vernacular names and a wide diversity of uses, including poor appetite, indigestion, stomach complaints, dysentery, colds, influenza, kidney conditions, fever, diabetes, internal cancers, uterine troubles, liver conditions, backache, rheumatoid arthritis, urinary tract infections, stress and anxiety, dropsy and heart failure. Notable is the use as a bitter tonic ("blood purifier"), anti-stress medication ('musa-pelo) and, at least since 1895, specifically as a cancer tonic (both as treatment and as prophylaxis). Externally it is applied to haemorrhoids, inflamed wounds and eye infections. Recent in vitro and in vivo studies have shown antiproliferative, anti-HIV, anti-diabetic, anti-inflammatory, analgesic, antibacterial, anti-stress, anticonvulsant and antithrombotic activities. Aqueous extracts often differ in activity from organic solvent extracts. The presence of high levels of free amino acids, non-protein amino acids such as canavanine and GABA, the cyclitol pinitol, flavonols and triterpenes (including SU1, a cycloartane-type triterpene saponin) provide plausible hypotheses on how these compounds, individually or collectively, may be responsible for the reputed efficacy in a wide range of ailments. Results of animal studies, as well as a phase I clinical study, have shown no indications of toxicity. Sufficient preclinical data are now available to justify controlled clinical studies. 相似文献
153.
Rooibos (Aspalathus linearis (Brum.f) Dahlg.) and honeybush (Cyclopia Vent. species) are popular indigenous South African herbal teas enjoyed for their taste and aroma. Traditional medicinal uses of rooibos in South Africa include alleviation of infantile colic, allergies, asthma and dermatological problems, while a decoction of honeybush was used as a restorative and as an expectorant in chronic catarrh and pulmonary tuberculosis. Traditional medicinal uses of Athrixia phylicoides DC., or bush tea, another indigenous South African plant with very limited localised use as herbal tea, include treatment of boils, acne, infected wounds and infected throats. Currently rooibos and honeybush are produced for the herbal tea market, while bush tea has potential for commercialisation. A summary of the historical and modern uses, botany, distribution, industry and chemical composition of these herbal teas is presented. A comprehensive discussion of in vitro, ex vivo and in vivo biological properties, required to expand their applications as nutraceutical and cosmeceutical products, is included, with the main emphasis on rooibos. Future research needs include more comprehensive chemical characterisation of extracts, identification of marker compounds for extract standardisation and quality control, bioavailability and identification of bio-markers of dietary exposure, investigation of possible herb-drug interactions and plant improvement with regards to composition and bioactivity. 相似文献
154.
泛素蛋白酶体途径是生物中特异的蛋白质降解系统之一。它参与体内许多重要的生理过程,临床中许多疾病的发生都与该途径的激活有关。高氧将产生氧自由基,引起细胞损伤、凋亡、坏死,同时引起炎性介质产生、炎性细胞浸润,从而产生肺部炎性反应、组织损伤和异常修复发生。本文将探讨泛素蛋白酶体途径的组成、功能及其在高氧肺损伤发病机制的作用。 相似文献
155.
目的:比较胸腔镜下肺大泡切除后机械法和化学法固定胸膜的疗效。方法将48例行胸腔镜下肺大泡切除术患者随机分成2组,每组24例,分别行胸膜剥脱术(A组)和红霉素法(B组)固定胸膜,观察2组手术中出血量、术后止痛剂用量、胸管放置时间、胸管引流量、住院时间及术后并发症情况。结果2组术中出血量比较无显著差异,A组在术后止痛剂用量、胸管放置时间、胸管引流量、住院时间及术后并发症方面优于B组。结论胸腔镜下肺大泡切除术后行胸膜剥脱术固定胸膜,安全有效,围术期效果优于红霉素法固定胸膜。 相似文献
156.
157.
利用全自动人模拟吸烟机采集香烟主流烟气凝相物,对其主要诱变物进行分析比较、结果表明:复合滤嘴能有效减少主流烟气Bap、焦油、TPM、烟碱、210P。、Cd和Pb诱变物,滤除率分别为83.9~93.5%、43.3~54.4%、43.3~53.7%、17.0~57.5%、56.1~69.3%、72.9~98.2%、53.2~75.5%。对BaP、Cd、Pb和210P。滤除率明显高于醋酸纤维滤嘴,对于减少诱变物在肺内沉积具有积极的意义和较大的应用价值。本文提出BaP、210P。应作为香烟质量和滤嘴滤效评价指标。 相似文献
158.
目的 了解2008-2010年产科病房孕产妇围生期生殖道感染病原菌的构成特点及其耐药性变化,为临床合理使用抗菌药物提供依据,并为加强控制医院感染的发生提供实验室诊断.方法 对产科病房2008-2010年生殖道标本所分离出的病原菌及其耐药性进行回顾性调查分析.结果 送检标本共2047份,检出病原菌88株,检出率4.3%;前4位病原菌依次为大肠埃希菌、金黄色葡萄球菌、肺炎克雷伯菌、无乳链球菌,分别占28.4%、26.2%、10.2%、6.8%;金黄色葡萄球菌、革兰阴性杆菌和链球菌属对常用抗菌药物耐药较为严重,且呈多药耐药性,耐甲氧西林金黄色葡萄球菌(MRSA)检出率为21.7%,革兰阴性杆菌产超广谱β-内酰胺酶(ESBLs)检出率为17.4%.结论 进行病原学监测,了解病原菌构成及其耐药趋势,对合理选择抗菌药物、降低围生期生殖道细菌感染发生率、减少耐药菌株产生和控制医院感染暴发和流行均有重要价值. 相似文献
159.
目的探讨丹参的临床新用途,为临床应用提供依据。方法查阅相关文献,进行分析和归纳。结果丹参的药理作用极其广泛.包括心肌保护、扩张血管、抗动脉粥样硬化、抗血栓、改善微循环、调节组织修复和再生、抗菌消炎等作用,近来对其作用机制有了进一步的研究,同时又发现其具有抗肿瘤、抗氧化等作用。结论丹参的药理作用,疗效确切,值得临床推广使用。 相似文献
160.
目的调查黄山地区储藏物中粉螨群落的物种组成和多样性。方法采集30种储藏物样本,分别进行粉螨的分离、计数及鉴定,并利用统计学方法进行多样性分析。结果30种储藏物中共检获粉螨19种,分别隶属于7科17属。粉螨的平均孳生密度为68.67只/克,物种丰富度指数为1.47,物种多样性指数为3.16,物种均匀度指数为1.07。结论储藏物中粉螨的孳生密度较大,其群落组成多样化。 相似文献