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61.
62.
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
63.
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
64.
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
65.
总结肾上腺良性无功能瘤39例,其中33例因健康查体或其他疾病就诊时发现,仅6例因腰腹不适或腹部包块而就诊。肾上腺内分泌激素检查均正常。肿瘤位于一侧肾上腺的38例,双侧的1便。30例病灶直径〉2.2cm的患者经治疗,病理结果:肾上腺皮质腺瘤22例,蛹地腺髓性脂肪瘤4例,肾上腺节能细胞神经瘤2例,肾上腺囊肿1例,肾上腺神经鞘瘤1例。对肾上腺无功能瘤的诊断和治疗进行了讨论。 相似文献
66.
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
67.
乳腺癌的新辅助化疗不但可以降低临床分期、提升保乳率,还可以判断化疗药物的敏感性,并指导术后化疗用药,已逐渐成为乳腺癌综合治疗的首选。但仍有少数乳腺癌患者不能从新辅助化疗中受益,预测乳腺癌新辅助治疗的获益人群,是临床中亟待解决的问题。乳腺癌新辅助化疗后的细胞凋亡指数(apop-totic index,AI)是评估乳腺癌新辅助化疗疗效的关键因素,而Apaf-1作为凋亡途径的重要一员,在细胞凋亡中起到重要的作用。本文通过乳腺癌新辅助化疗后AI值的变化,并结合Apaf-1自身的结构、分布、在凋亡途径中的作用及在各肿瘤中的表达和化疗耐药性等角度,对Apaf-1在乳腺癌治疗中的作用及意义作一综述。 相似文献
68.
Baruffi RL Mauri AL Petersen CG Felipe V Martins AM Cornicelli J Cavagna M Oliveira JB Franco JG 《Reproductive biomedicine online》2007,14(1):14-25
This study aims to compare the efficacy of recombinant LH (rLH) supplementation for ovarian stimulation in gonadotrophin-releasing hormone-antagonist protocol for IVF/intracytoplasmic sperm injection cycles. Search strategies included online surveys of databases. The fixed effects model was used for odds ratio (OR) and effect size (weighted mean difference, WMD). Five trials fulfilled the inclusion criteria. When the meta-analysis was carried out, advantages were observed for the LH supplementation protocol with respect to higher serum oestradiol concentrations on the day of human chorionic gonadotrophin administration P < 0.0001; WMD: 514, 95% CI 368, 660) and higher number of mature oocytes (P = 0.0098; WMD: 0.88, 95% CI 0.21, 1.54). However, these differences were not observed in the total amount of recombinant FSH (rFSH) administered, days of stimulation, number of oocyets retrieved, the clinical pregnancy rate per oocyte retrieval, the implantation rate and miscarriage rate. This result demonstrates that the association of rLH with rFSH may prevent any decrease in oestradiol after antagonist administration and that a significantly higher number of mature oocytes was available for laboratory work. Nevertheless, it failed to show any statistically significant difference in clinically significant end-points in IVF (implantation and pregnancy rates). Additional randomized controlled trials are needed to confirm these results further. 相似文献
69.
Xi-Qun Shao Yong-Jun Wen Heng-Xing Ba Xiu-Ting Zhang Zhi-Gang Yue Ke-Jian Wang Chun-Yi Li Jianming Qiu Fu-He Yang 《Emerging infectious diseases》2014,20(12):2085-2088
A new amdoparvovirus, named raccoon dog and fox amdoparvovirus (RFAV), was identified in farmed sick raccoon dogs and arctic foxes. Phylogenetic analyses showed that RFAV belongs to a new species within the genus Amdoparvovirus of the family Parvoviridae. An RFAV strain was isolated in Crandell feline kidney cell culture. 相似文献
70.