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101.
Nematicidal bioassay-guided fractionation of the n-hexane extract of the seeds of Jubaea chilensis led to the identification of eight known fatty acids and a mixture of triglycerides, reported for the first time for this species. In addition, their corresponding methyl esters were identified to be artifacts generated during the extraction and isolation procedures by using GC-EI-MS and chemical transformation methods. The fatty acid composition of the triglycerides was analyzed by GC-EI-MS and chemical transformation techniques. Among the 17 compounds, only lauric acid and myristic acid exhibited significant inhibitory effects on the movement of Caenorhabditis elegans with minimum inhibitory concentrations (MIC) of 75 microg/ml.  相似文献   
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OBJECTIVE: To measure thyroid cell proliferation in patients with Graves' disease (GD) before and during treatment with antithyroid drugs. STUDY DESIGN: Patients were assessed by fine needle aspiration biopsy before (n = 20) and after 4 (n = 19) and 12 months of treatment (n = 15) with propylthiouracil or methimazole. Cell proliferation index (CPI) was estimated by immunocytochemistry using MIB-1. CPI was studied in relation to the cytologic parameters of the smears; clinical parameters, such as Wayne's Clinical Index (WCI) and time without treatment; laboratory parameters, such as 131I uptake and dosage of serum free thyroxin and thyroid-stimulating hormone; and thyroid ultrasound. RESULTS: CPI varied from 0.00% to 25.00% before treatment, 0.00% to 23.00% at 4 months and 0.00% to 14.84% at 12 months. CPI median values were 6.50%, 4.30% and 3.30%, respectively (before and after 4 months and 12 months of treatment). CPI had a positive correlation with WCI and FT4 at 12 months of treatment. CONCLUSION: Thyroid CPI in GD varies from case to case. However, due to its decreasing pattern during follow-up and its positive correlation with thyrotoxicosis severity, CPI may indicate the functional status of the gland and contribute to a better understanding of GD.  相似文献   
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Alpha-L-fucosidase (FUC) is a glycosidase involved in the degradation of fucose-containing glycoconjugates. A cDNA representing the complete sequence of human FUC was inserted into the prokaryotic expression vector pGEX-2T. High levels of the glutathione S-transferase (GST) fusion protein were detected in Escherichia coli cells after induction with isopropyl thio-beta-D-galactopyranoside. The GST-FUC protein was mostly found as inclusion bodies and attempts to optimise its expression as a soluble form were unsuccessful. Nevertheless, the recombinant protein was purified by affinity chromatography on glutathione-sepharose and its fucosidase activity was characterised. After thrombin cleavage of the GST tag, the FUC precursor protein was purified by electro-elution.  相似文献   
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The flavonoids 5-hydroxy-7-methoxyflavanone, 6,8-dimethyl-5,7-dihydroxyflavanone and 2',4'-dihydroxy-6'-methoxy-3',5'-dimethylchalcone, a mixture of alkyl esters of p-coumaric acid, the triterpenoids oleanolic acid and maslinic acid, the monoterpenoid 1 alpha,2 beta,4 beta-trihydroxy-p-menthane, the sesquiterpenoid clovandiol and beta-sitosterol were isolated from the aerial parts of Luma gayana (Barn.) Burret. This is the first report on the chemistry of this species.  相似文献   
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We studied the effect of heat shock and wood-fueled smoke on the emergence of native and exotic plant species in soil samples obtained in an evergreen shrubland of central Chile, located on the eastern foothills of the Coastal Range of Lampa. Immediately after collection samples were dried and stored under laboratory condition. For each two transect, 10 samples were randomly chosen, and one of the following treatments was applied: 1) Heat-shock treatment. 2) Plant-produced smoke treatment. 3) Combined heat-and-smoke treatment. 4) Control, corresponding to samples not subjected to treatment. Twenty-three species, representing 12 families, emerged from the soil samples. The best-represented families were Poaceae and Asteraceae. All of the emerged species were herbs, 21 were annuals, and 14 were exotic to Chile. Fire-related triggers used in this study did not increase the emergence and/or abundance of exotic species with respect to natives in soil samples. Interestingly, this study provides evidence that heat-shock can increase the emergence of native herbs.  相似文献   
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Objectives: To record self‐reported hygiene habits, examine the oral conditions of a sample group of institutionalised elderly, and examine possible relationships between these habits and conditions. Design: Cross‐sectional. Setting: All the institutions for the elderly in Taubaté, Brazil. Subjects: The entire population of these institutionalised elderly people (n = 553). Intervention: The subjects were interviewed and underwent an oral examination. Main outcome measures: Oral hygiene habits, oral conditions and statistical relationships between habits and oral conditions were recorded. Results: The average age of the subjects who knew their age (n = 364) was 74.9 years (±12.9), and 64.7% of the sample group were females. Denture‐related stomatitis was found in 19.5%, impaired manual dexterity in 40%, dry mouth sensation in 36.3%, difficulty in performing oral hygiene in 20%, no oral hygiene‐related orientation in 54.1%, no periodic oral examinations in 59.5%, and no tongue cleaning in 68.3% was declared. Among dentate subjects, 73.3% had periodontal disease, 54.7% had caries, 26% reported no toothbrushing, and 7.3% reported flossing. Of the denture wearers, 7% did not brush their dentures. Denture‐related stomatitis showed a statistical relationship with impaired manual dexterity (p = 0.012) and an inverse statistical relationship with denture brushing frequency (p = 0.006). Periodontal disease showed an inverse relationship to flossing (p < 0.001) and tongue cleaning (p = 0.0026). Caries showed an inverse relationship with tooth‐brushing (p = 0.043), flossing (0.022), proper oral hygiene orientation (p = 0.041) and periodical check‐ups (p = 0.007). Conclusion: Oral hygiene practices in this sample group were found to be inadequate, and statistically significant relationships were verified between the lack of good oral hygiene practices and the deleterious oral conditions.  相似文献   
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Biotin–iminosugar conjugates of different configuration such as d-gluco, d-galacto, l-ido as well as a furanoid representative in the d-manno configuration have been synthesised and exhibit powerful inhibition of β-glucosidase from Agrobacterium sp. with Ki values in the range of the respective parent compounds. Such molecular probes have potential for activity-based protein profiling taking advantage of the biotin–(strept)avidin interaction.  相似文献   
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