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71.
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   
72.
Earlier in vitro studies of the compounds marked as GT27, GT28, GT29 and BM128 revealed their inhibitory action towards murine γ-aminobutyric acid (GABA) transporters (mGAT1-mGAT4). In the present paper, the pharmacological activity of four γ-hydroxybutyric acid (GHB) amide derivatives was investigated. The following procedures were involved: locomotor activity, hot plate and electroconvulsive threshold tests. The compounds' influence on motor coordination was evaluated in the chimney test, as well. Intraperitoneal (i.p.) administration of the GHB derivatives decreased animals' locomotor activity (ED(50) values ranged between 23.79 and 26.37 mg/kg). At a dose of 25 mg/kg (i.p.) the compounds prolonged the nociceptive reaction time latency in the hot plate assay to various degree and GT28 and GT29 were the most potent ones in this respect. Their analgesic efficacy was particularly pronounced 30 min after their administration [percent of maximal possible effect (%MPE) = 16.93 and 22.72, respectively]. The investigated GHB derivatives, except for GT29 at 100 mg/kg, increased the electroconvulsive threshold by approximately 4-11 mA as compared to the vehicle-treated mice. In the chimney test they impaired the animals' motor coordination to various degree. We suggest further investigations of the compounds to estimate their biological activity.  相似文献   
73.
279例耳闷胀感的病因分析   总被引:3,自引:0,他引:3  
目的 探讨产生耳闷胀感的部位和原因。方法 收集耳闷胀感为主诉的279例362耳,对患耳的临床表现、鼓室导抗图、纯音测听和咽鼓管功能进行分析。结果 362耳中鼓室导抗图A型203耳、B型111耳、C型33耳以及鼓膜穿孔15耳。纯音测听表现为传导性聋、感音神经性聋、混合性聋以及正常者分别是83耳、8l耳、105耳和93耳。在362耳中,咽鼓管功能异常208耳,在A型鼓室导抗图203耳中,咽鼓管功能异常67耳。结论 产生耳闷胀感的病变部位包括外、中、内耳和面神经的病变,其中以分泌性中耳炎、各种原因引起的感音神经性聋和“咽鼓管狭窄症”为多。  相似文献   
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Six new triterpene saponins, 3-O-alpha-L-rhamnopyranosyl-(1-->2)-beta-D-xylopyranosyl-(1-->2)-beta-D-glucuronopyranosyl-21-epi-kudzusapogenol A (1), 3-O-alpha-L-rhamnopyranosyl-(1-->2)-beta-D-glucopyranosyl-(1-->2)-beta-D-glucuronopyranosyl-21-epi-kudzusapogenol A (2), 3-O-alpha-L-rhamnopyranosyl-(1-->2)-beta-D-xylopyranosyl-(1-->2)-beta-D-glucuronopyranosyl-22-O-beta-D-glucopyranosyl-21-epi-kudzusapogenol A (3), 3-O-alpha-L-rhamnopyranosyl-(1-->2)-beta-D-glucopyranosyl-(1-->2)-beta-D-glucuronopyranosyl-22-O-beta-D-glucopyranosyl-21-epi-kudzusapogenol A (4), 3-O-alpha-L-rhamnopyranosyl-(1-->2)-beta-D-xylopyranosyl-(1-->2)-beta-D-glucuronopyranosyl-22-O-alpha-L-arabinopyranosyl-21-epi-kudzusapogenol A (5), and 3-O-alpha-L-rhamnopyranosyl-(1-->2)-beta-D-glucopyranosyl-(1-->2)-beta-D-glucuronopyranosyl-22-O-alpha-L-arabinopyranosyl-21-epi-kudzusapogenol A (6), were isolated from the roots of Astragalus flavescens, together with the known trajanoside B, azukisaponin V, and astragalosides IV, VII, and VIII. Their structures were established mainly by 2D NMR techniques and mass spectrometry.  相似文献   
76.
Ethnopharmacological relevance: Rhododendron ponticum L. (Ericaceae) is used for the treatment of inflammatory diseases and to alleviate rheumatic pain and against toothache in Turkish traditional medicine.  相似文献   
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Hypoxia treatment of normal peritoneal fibroblasts results in alterations that are characteristic for fibroblasts obtained from postoperative peritoneal adhesion tissue. In this study, we have shown that hypoxia treatment enhances normal peritoneal fibroblast elimination by lymphokine-activated killer cells to the level of adhesion tissue fibroblasts, suggesting a pivotal role of hypoxia in the adhesion development.  相似文献   
80.
OBJECTIVE: To establish the adenosine deaminase (ADA) activity in women who had been pregnant with a child suffering from central nervous system (CNS) anomaly. METHODS: The study group comprised 68 women who had been pregnant with an affected child, and 68 controls matched for age, gestational age and body mass index. Maternal venous blood was collected for measurement of ADA levels. We defined the diagnostic sensitivity, specificity and area under receiver-operating characteristic curve for ADA. RESULTS: Plasma ADA activity was significantly higher in the study group (12.3 U/L, range 1.7-33.3) compared to the median value of 3.3 U/L (range 1.1-34.4) in normal pregnancies (P<0.05). The cut-off point of ADA >5.9 U/L was associated with the highest combination of specificity (58.8%) and sensitivity (86.8%). CONCLUSION: ADA activity in women who have conceived a fetus with CNS malformations was significantly higher than that in normal pregnant women.  相似文献   
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