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91.
Viljoen AM Subramoney S van Vuuren SF Başer KH Demirci B 《Journal of ethnopharmacology》2005,96(1-2):271-277
Lippia javanica is widely distributed throughout South Africa where it is used extensively in traditional herbal preparations. An infusion of the leaves is commonly used as a decongestant for colds and coughs. A preliminary study indicated that the essential oil chemistry varies dramatically both within and between natural plant populations. As the antimicrobial activity may be directly related to the specific composition of the oil, the activity may also fluctuate. The aerial parts of Lippia javanica were collected from various localities in southern Africa to study the essential oil composition and the antimicrobial activity thereof. The hydrodistilled essential oils were analysed by GC/MS and a cluster analysis was performed on the essential oil dataset. From 16 samples (representing five natural populations), 5 chemotypes were identified; a myrcenone rich-type (36-62%), a carvone rich-type (61-73%), a piperitenone rich-type (32-48%), an ipsenone rich-type (42-61%) and a linalool rich-type (>65%). The myrcenone and linalool chemotypes have been mentioned in the literature but the carvone, ipsenone and piperitenone chemotypes have not previously been reported for Lippia javanica. Time kill studies were performed on three microbial respiratory isolates to document the scientific rationale of using Lippia to treat respiratory complaints in traditional herbal medicine. Klebsiella pneumoniae, Cryptococcus neoformans and Bacillus cereus showed reduction in microbial populations with the strongest bacteriostatic effect observed for Klebsiella pneumoniae. 相似文献
92.
目的:检测连翘-4味汤散不同溶剂提取物对临床常见致病菌体外抗菌作用。方法:采用琼脂平板稀释法、微孔板TTC法,以连翘-4味汤散不同溶剂(石油醚、氯仿、乙酸乙酯、无水乙醇、75%乙醇、水)提取物为实验药物,选用临床分离鉴定的,耐药现象较普遍的11种常见致病菌株为供试菌,检测实验药物的最小抑菌浓度(MIC)和最小杀菌浓度(MBC)。结果:实验所用6种药物提取物,对金黄色葡萄球菌、表皮葡萄球菌、肠球菌、枯草芽胞杆菌、炭疽芽胞杆菌、大肠埃希菌、肺炎克雷伯菌、鲍曼不动杆菌、铜绿假单胞菌、阴沟杆菌、白假丝酵母菌等11种供试菌种,表现出了较为普遍的抑菌作用和一定的杀菌作用。结论:体外抗菌实验结果显示,实验药物表现出了较高的抗菌效能,连翘-4味汤散做为传统方剂,具有一定的药剂学和药理学研发价值。 相似文献
93.
Effects of pesticides on human peripheral lymphocytes in vitro: induction of DNA damage 总被引:6,自引:0,他引:6
Because of the widespread use of pesticides for domestic and industrial applications the evaluation of their genotoxic effects is of major concern to public health. Although various experimental data have provided evidence that pesticides can possess genotoxic properties in animals and in in vitro test systems after acute and chronic exposure, the information on the genotoxic effects of some of pesticides is limited and inconsistent. In the present study, the genotoxic potential of commonly used pesticides (i.e., dimethoate and methyl parathion from the organophosphate class, propoxur and pirimicarb from carbamates, and cypermethrin and permethrin from pyrethroids) have been evaluated. The genotoxic effects of these substances were examined using the single cell gel electrophoresis (comet) assay in freshly isolated human peripheral lymphocytes. The cells were incubated with 10, 50, 100 and 200 µg/ml concentrations of the test substances for 0.5 h at 37°C and DNA damage was compared with that obtained in lymphocytes from the same donor not treated with substances. Hydrogen peroxide, 100 µM, was used as a positive control. Within the concentration ranges studied, no significant cytotoxic effects were observed. Dimethoate and methyl parathion at 100 and 200 µg/ml; propoxur at 50, 100 and 200 µg/ml, and pirimicarb, cypermethrin and permethrin at 200 µg/ml significantly increased DNA damage in human lymphocytes. 相似文献
94.
为了更好地开展国家中医临床研究基地重点病种建设与中医医疗与临床科研信息共享系统(以下简称“共享系统”)建设,湖北省中医院构建了研究型门诊。研究型门诊以“真实世界中医临床科研范式”为建设理念,从临床研究、健康管理、特色诊疗三个方面进行真实世界中医肝病临床研究体系构建模式的探索与应用,为研究型门诊及研究型医院的建设提供参考。 相似文献
95.
Zhi-yuan Li Qiang Ma Xing Li Shui-yuan Yu Juan Zuo Chong-jian Wang Wen-jie Li Yue Ba Fang-fang Yu 《Medicine》2022,101(29)
The objective was to determine the potential associations of the angiotensin II receptor type 1 (AGTR1) gene polymorphism, methylation, and lipid metabolism in Chinese farmers with hypertension.A case-control study was conducted in Wuzhi county of Henan province in China in 2013 to 2014. A total of 1034 local residents (35–74 years, 386 hypertensive cases, and 648 normotensive subjects) were enrolled in this study. Triglyceride (TG), total cholesterol (TC), high-density lipoprotein, and low-density lipoprotein were measured using automatic chemistry analyzer. The AGTR1 gene promoter methylation level was measured using quantitative methylation-specific polymerase chain reaction method. The single nucleotide polymorphism rs275653 was genotyped with TaqMan probe assay at an applied biosystems platform.The gender, body mass index (BMI), TG, TC, and family history of hypertension in the hypertension group were significantly higher than those in control group (P < .05). No significant difference was observed in the distribution of AGTR1 rs275653 polymorphism in the hypertension and controls (P > .05). The AGTR1 gene methylation in subjects carrying different genotypes was not significantly observed (P > .05). The logistic regression analysis found the AGTR1 gene methylation level was negative correlation with hypertension in the present study (odds ratio, 0.946, 95% confidence interval, 0.896–0.999) through adjusting for age, gender, BMI, education, smoking, alcohol drinking, fruit and vegetable intake, pickles intake, and family history of hypertension.The association of AGTR1 gene hypomethylation and essential hypertension was observed in Chinese farmers; no significant difference was observed in the distribution of AGTR1 rs275653 polymorphism. 相似文献
96.
目的了解金昌队列人群非酒精性脂肪肝(NAFLD)发病的影响因素,为NAFLD的预防和控制提供科学依据。方法以金昌队列基线未患脂肪肝且符合纳入标准的20051人为研究对象,通过前瞻性队列研究及Cox回归分析探讨NAFLD发病影响因素,并用限制性立方样条法研究相关生化指标与NAFLD发病风险的剂量反应关系。结果NAFLD发病密度为42.37/1000人年,多因素Cox回归分析显示,职业为工人与技术人员(工人:HR=0.84,95%CI:0.70~0.99;技术人员:HR=0.73,95%CI:0.56~0.95)、饮茶(正在饮:HR=0.86,95%CI:0.78~0.94;过去饮:HR=0.52,95%CI:0.31~0.86)、体育锻炼(偶尔:HR=0.79,95%CI:0.68~0.91;经常:HR=0.60,95%CI:0.52~0.69)、体重较轻(HR=0.10,95%CI:0.05~0.22)、奶类及奶制品摄入>300 ml/d(HR=0.78,95%CI:0.71~0.87)、HBV感染(HR=0.77,95%CI:0.60~0.99)是NAFLD的保护因素;职业为内勤服务人员(HR=1.84,95%CI:1.46~2.31)、家庭人均月收入≥2000元(2000~元:HR=1.32,95%CI:1.04~1.66;≥5000元:HR=1.72,95%CI:1.11~2.66)、文化程度为本科及以上(HR=1.35,95%CI:1.03~1.76)、超重(HR=2.31,95%CI:2.08~2.55)、肥胖(HR=3.95,95%CI:3.42~4.56)、空腹血糖受损(HR=1.31,95%CI:1.17~1.47)、糖尿病(HR=1.53,95%CI:1.30~1.80)、TC升高(HR=1.37,95%CI:1.24~1.52)、TG升高(HR=1.79,95%CI:1.62~1.98)、HDL-C降低(HR=1.29,95%CI:1.14~1.45)、ALT升高(HR=1.13,95%CI:1.01~1.26)和高脂饮食(HR=1.24,95%CI:1.11~1.40)是NAFLD的危险因素,TC、TG、HDL-C、ALT、FPG与NAFLD发病呈良好的剂量反应关系。结论职业、文化程度、家庭人均月收入、饮茶、体育锻炼、BMI、FPG、血脂、ALT、HBV、饮食与NAFLD发病有关。 相似文献
97.
Ming Bai Meng Wang Ting Deng Yuxian Bai Kai Zang Zhanhui Miao Wenlin Gai Liangzhi Xie Yi Ba 《癌症生物学与医学(英文版)》2022,19(3):358-369
Objective: The mainstay treatment of esophageal squamous cell carcinoma(ESCC) involves chemotherapy and immunotherapy. However, alternative therapies are required for patients who are refractory or intolerant to existing therapies.Methods: In this single-arm, multicenter, open-label phase Ib study, 30 patients received an intravenous infusion of SCT200, an antiepidermal growth factor receptor(EGFR) monoclonal antibody, 6.0 mg/kg once a week for 6 weeks, followed by 8.0 mg/kg once every 2 weeks u... 相似文献
98.
99.
目的探讨阑尾杯状细胞腺癌(goblet cell adenocarcinomas,GCA)的临床病理学特征及免疫表型特征,分析其生物学行为。方法收集北京大学第一医院2015—2018年诊断的7例GCA的临床资料,进行形态学观察,按照2019年WHO消化系统肿瘤分类第5版重新分级,并行免疫组织化学EnVision法染色及电镜观察,随访患者并复习相关文献。结果7例患者中男性2例,女性5例;年龄48~72岁,中位年龄58岁。1例为阑尾游离端出现局限性肿物,切面灰白实性,质地中等;其余6例阑尾弥漫增粗;镜下观察均可见低级别GCA,5例同时伴有高级别GCA,3例分级为1级,3例分级为2级及1例分级为3级。6例可见神经侵犯,1例可见脉管癌栓。免疫组织化学染色嗜铬粒素A、突触素、CD56、广谱细胞角蛋白、癌胚抗原、细胞角蛋白20、MLH1、MSH2、MSH6和PMS2均阳性,Ki-67阳性指数5%~50%,p53在高级别GCA的表达强度及阳性细胞数高于低级别GCA。随访14~46个月,6例患者生存,1例患者死亡。结论GCA为阑尾较少见的肿瘤,同时具有神经内分泌及腺上皮的分化,生物学行为从惰性到高度侵袭性均可。 相似文献
100.