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91.
Effect of extraction methods on characteristic and composition of Indonesian cashew nut shell liquid
Long chain phenols contained in cashew nut shell liquid (CNSL) are found to have important pharmaceutical applications, such as antitumor, antimicrobial, urease inhibitory and lipoxygenase activities, and also are well known in coating and resin industry. The impact of different extraction methods on CNSL yield, selectivity towards preferable compounds, composition and characteristic of extracts was investigated. Four different methods employed in extracting CNSL from CNS were: supercritical carbon dioxide (SC-CO2) extraction (40 °C, 300 bar, 4 h), subcritical water (SCW) extraction (140 °C, 22 bar, 1 h), soxhlet extraction (solvent boiling point, atmospheric pressure, 30 h), and two-step extraction, which comprises a solvent extraction followed by a SCW extraction. Characteristic of the extracts differed significantly. Methanol and two-step extraction resulted in darker and more turbid extracts, while n-hexane and SC-CO2 extracts were clearer and lighter in color. GC-FID/MS chromatograms showed differences in compositions of the extracts obtained by different methods. Two-step extraction yielded extracts that contain 81.17-82.98% total long chain phenols (around 50% based on dry CNS) with monounsaturated cardanol as the major compound, producing higher amount of total phenols than other methods. SCW extraction showed high selectivity towards monounsaturated cardanol and stigmasterol, while high concentration of monounsaturated anacardic acid and cardol appeared in SC-CO2 extract. 相似文献
92.
Teng‐Yu Tsai Shao‐Kuang Chang Po‐Yen Chou Lih‐Seng Yeh 《Veterinary anaesthesia and analgesia》2013,40(6):615-622
ObjectiveTo compare the postoperative analgesic effects of intravenous (IV) lidocaine, meloxicam, and their combination in dogs undergoing ovariohysterectomy.Study designProspective, randomized, double‐blind, controlled clinical trial.AnimalsTwenty‐seven dogs aged (mean ± SD) 16.1 ± 7.5 months and weighing 22.4 ± 17.9 kg scheduled for ovariohysterectomy.MethodsAnaesthesia was induced with propofol and maintained with isoflurane. Dogs (n = 9 in each group) were allocated to receive just prior to and during surgery one of the following regimens: M group, 0.2 mg kg?1 IV meloxicam then a continuous rate infusion (CRI) of lactated Ringer's at 10 mL kg?1 hour?1; L group, a bolus of lidocaine (1 mg kg?1 IV) then a CRI of lidocaine at 0.025 mg kg?1 minute?1; and M + L group, both the above meloxicam and lidocaine treatments. Pain and sedation were scored, and venous samples taken for serum cortisol and glucose measurement before and at intervals for 12 hours after anaesthesia. Pain scores were assessed using a multi‐parameter subjective scoring scale (cumulative scale 0–21) by three observers. The protocol stated that dogs with a total score exceeding 9 or a sub‐score above 3 in any one category would receive rescue analgesia. Sedation was scored on a scale of 0–4.ResultsThere were no significant differences in subjective pain scores, serum cortisol, and glucose concentrations between the three groups. The highest pain score at any time was 5, and no dog required rescue analgesia. None of the three regimens caused any observable side effects during or after anaesthesia. At 1 and 2 hours after extubation dogs in group L were significantly more sedated than in the other two groups.Conclusions and Clinical relevanceThis study suggests that, with the scoring system used, IV lidocaine and meloxicam provide similar and adequate post‐operative analgesia in healthy dogs undergoing ovariohysterectomy. 相似文献
93.
Effects of phenolic acids on human phenolsulfotransferases in relation to their antioxidant activity
Sulfate conjugation by phenolsulfotransferase (PST) enzyme is an important process in the detoxification of xenobiotics and endogenous compounds. There are two forms of PST that are specific for the sulfation of small phenols (PST-P) and monoamines (PST-M). Phenoilc acids have been reported to have important biological and pharmacological properties and may have benefits to human health. In the present study, human platelets were used as a model to investigate the influence of 13 phenolic acids on human PST activity and to evaluate the relationship to their antioxidant activity. The results showed that chlorogenic acid, syringic acid, protocatechuic acid, vanillic acid, sinapic acid, and caffeic acid significantly (p < 0.05) inhibited the activities of both forms of PST by 21-30% at a concentration of 6.7 microM. The activity of PST-P was enhanced (p < 0.05) by p-hydroxybenzoic acid, gallic acid, gentisic acid, o-coumaric acid, p-coumaric acid, and m-coumaric acid at a concentration of 6.7 microM, whereas the activity of PST-M was enhanced by gentisic acid, gallic acid, p-hydroxybenzoic acid, and ferulic acid. The phenolic acids exhibited antioxidant activity as determined by the oxygen radical absorbance capacity (ORAC) assay and Trolox equivalent antioxidant capacity (TEAC) assay, especially gallic acid, p-hydroxybenzoic acid, gentisic acid, and coumaric acid, which had strong activity. The overall effect of phenolic acids tested on the activity of PST-P and PST-M was well correlated to their antioxidant activity of ORAC value (r = 0.71, p < 0.01; and r = 0.66, p < 0.01). These observations suggest that antioxidant phenolic acids might alter sulfate conjugation. 相似文献
94.
95.
The diversity of head-scab resistance in Triticeae and their relation to ecological conditions 总被引:3,自引:0,他引:3
1507 accessions from 93 species of 18 genera in Triticeae were screened for resistance to initial infection and resistance
to pathogen spread with multi-floret and single-floret injection inoculation methods respectively. The accessions with high
resistance were mainly found in perennial genera: Roegneria, Hystrix, Agropyron, Kengyilia and Elymus. Based on differences
in resistance, 18 genera screened in Triticeae could be classified into five groups. The species with high resistance were
mainly distributed in humid ecological environments.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
96.
本文采用聚丙烯酰胺凝胶电泳法,对鹅观草属和披碱草属共12个四倍体种的幼根、幼芽进行了酯酶同工酶分析。用数学方法对所分析的酶谱进行了聚类分析。结果表明R.abolinii var.divaricus和R.dolichathera, R. ciliaris和R.hondai, R.gmelinii和R.strict, R.angustiglumis和R.komarovii间在幼根和幼芽上的酶谱均表现很相似,分别被聚在一起,而E.angustiglumus和R.komarovii聚在一起与染色体组分析相矛盾。说明同工酶虽然可以鉴别种内和种间差异,但不能反映属种间亲缘的关系。 相似文献
97.
Yen JL Kellermann KI Rayhrer B Broten NW Fort DN Knowles SH Waltman WB Swenson GW 《Science (New York, N.Y.)》1977,198(4314):289-291
The Hermes satellite, a joint Canadian-American program, has been used to provide a communication channel between radio telescopes in West Virginia and Ontario, for very-long-baseline interferometry (VLBI). This system makes possible instantaneous correlation of the data as well as a sensitivity substantially better than that of earlier VLBI systems, by virtue of a broader observational bandwidth. With the use of a geostationary communications satellite it is possible to eliminate the tape recorders and the most troublesome part of the postobservational data processing. A further possibility is the development of a phase-coherent interferometer. 相似文献
98.
Philip D. Koblik DVM MS Chi-Kwan Yen MD Jan Komtebedde DVM William J. Hornof DVM MS Peter F. Moore BvSc PhD Paul E. Fisher MS 《Veterinary radiology & ultrasound》1990,31(4):170-174
Shunt fraction was determined using transcolonic 123 I-iodoamphetamine (IMP) and portal vein injection of 99m Tc-macroaggregated albumin (MAA) in a group of eight dogs with chronic cirrhosis and acquired portosystemic shunts subsequent to total common bile duct ligation. Hepatic parenchymal damage was confirmed by alterations in liver function tests and liver histology. Seven of the eight dogs developed portal hypertension and had angiographic evidence of hepatofugal portal blood flow with multiple peripheral portosystemic anastomoses. Shunt fractions determined in the seven dogs with shunts varied from 39 to 100 using IMP and 45 to 93 using MAA. The remaining dog had normal portal pressure, a normal portal angiogram, and normal IMP and MAA scintigraphic studies. There was an excellent correlation between the two methods of shunt fraction calculation (R2 = 0.98) and the line of regression was not significantly different from unity (IMP = 1.09 × MAA - 0.03). 相似文献
99.
Background
We have developed a functional genomics approach based on expression cloning in Xenopus oocytes to identify plant transporter function. We utilized the full-length cDNA databases to generate a normalized library consisting of 239 full-length Arabidopsis thaliana transporter cDNAs. The genes were arranged into a 96-well format and optimized for expression in Xenopus oocytes by cloning each coding sequence into a Xenopus expression vector. 相似文献100.
Yong-Hong Zhou Chi Yen Jun-Liang Yang You-Liang Zheng 《Genetic Resources and Crop Evolution》1999,46(4):315-317
Cytogenetic studies of Hystrix duthiei (2n=28) from China, Hystrix longearistata (2n=28) from Japan and their artificial hybrids were carried out. The F1 hybrids showed a very high degree of bivalent pairing at the meiotic Metaphase-I. No multivalents were found. Partial fertility of the hybrids was observed. The results indicated that they shared two highly homologous genomes and were closely related. 相似文献