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131.
Larvicidal activity of crude hexane, ethyl acetate, petroleum ether, acetone and methanol extracts of five medicinal plants,
Abutilon indicum, Aegle marmelos, Euphorbia thymifolia, Jatropha gossypifolia and Solanum torvum were assayed for their toxicity against the early fourth-instar larvae of Culex quinquefasciatus. The larval mortality was observed after 24 h exposure. All extracts showed moderate larvicidal effects; however, the highest
larval mortality was found in petroleum ether extract of A. indicum. In the present study, bioassay-guided fractionation of A. indicum led to the separation and identification of a β-sitosterol as a potential new mosquito larvicidal compound with LC50 value of 11.49, 3.58 and 26.67 ppm against Aedes aegypti L, Anopheles stephensi Liston and C. quinquefasciatus Say (Diptera: Culicidae), respectively. 1H NMR, 13C NMR and mass spectral data confirmed the identification of the active compound. β-sitosterol has been recognized as the
active ingredient of many medicinal plant extracts. All the crude extracts when screened for their larvicidal activities indicated
toxicity against the larvae of C. quinquefasciatus. This article reports the isolation and identification of the β-sitosterol as well as bioassay data for the crude extracts.
There are no reports of β-sitosterol in the genus A. indicum, and their larvicidal activities are being evaluated for the first time. Results of this study show that the petroleum ether
extract of A. indicum may be considered as a potent source and β-sitosterol as a new natural mosquito larvicidal agent. 相似文献
132.
Praharaj I Sujatha S Parija SC Gopalakrishnan MS 《Indian journal of medical microbiology》2012,30(2):242-245
Vancomycin-resistant enterococci rarely cause meningitis and present a therapeutic challenge. Antimicrobial susceptibility testing was done for strains of Enterococcus species isolated from CSF samples of patients with meningitis by phenotypic methods. Multiplex polymerase chain reaction was performed to determine the genetic basis of vancomycin resistance of such isolates. We report here two cases of enterococcal meningitis caused by vancomycin-resistant Enterococcus species. One of the isolates was identified as Enterococcus faecalis and the other as Enterococcus gallinarum. We also report the simultaneous presence of vanC1 and vanA resistance genes in the strain of E. gallinarum. To the best of our knowledge, this is the first report of vanA resistance gene in an isolate of E. gallinarum from the Indian subcontinent. This is also the first Indian report of vancomycin-resistant Enterococcus causing meningitis. 相似文献
133.
Roberts DM Smith MW Gopalakrishnan M Whittaker G Day RO 《Annals of emergency medicine》2011,58(1):83-85
γ-Hydroxybutyrate (GHB) and its precursor γ-butyrolactone (GBL) are commonly abused drugs with a narrow therapeutic index. Therefore, overdoses occur readily with recreational use, and severe poisoning can occur after deliberate self-poisoning. We report the sequelae in a patient who ingested a massive dose of GBL, with suicidal intent. Severe metabolic acidosis and an asystolic cardiac arrest were successfully treated with standard resuscitation, supportive care, and continuous venovenous hemodiafiltration. Plasma GHB concentrations were the highest reported to date. The acidosis was attributed to rapid systemic absorption of GBL, followed by rapid metabolism to GHB. 相似文献
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Ossandón T Vidal JR Ciumas C Jerbi K Hamamé CM Dalal SS Bertrand O Minotti L Kahane P Lachaux JP 《The Journal of neuroscience》2012,32(10):3414-3421
An object that differs markedly from its surrounding-for example, a red cherry among green leaves-seems to pop out effortlessly in our visual experience. The rapid detection of salient targets, independently of the number of other items in the scene, is thought to be mediated by efficient search brain mechanisms. It is not clear, however, whether efficient search is actually an "effortless" bottom-up process or whether it also involves regions of the prefrontal cortex generally associated with top-down sustained attention. We addressed this question with intracranial EEG (iEEG) recordings designed to identify brain regions underlying a classic visual search task and correlate neural activity with target detection latencies on a trial-by-trial basis with high temporal precision recordings of these regions in epileptic patients. The spatio-temporal dynamics of single-trial spectral analysis of iEEG recordings revealed sustained energy increases in a broad gamma band (50-150 Hz) throughout the duration of the search process in the entire dorsal attention network both in efficient and inefficient search conditions. By contrast to extensive theoretical and experimental indications that efficient search relies exclusively on transient bottom-up processes in visual areas, we found that efficient search is mediated by sustained gamma activity in the dorsal lateral prefrontal cortex and the anterior cingulate cortex, alongside the superior parietal cortex and the frontal eye field. Our findings support the hypothesis that active visual search systematically involves the frontal-parietal attention network and therefore, executive attention resources, regardless of target saliency. 相似文献
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Digestive Diseases and Sciences - 相似文献
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John A. Kalapurakal Bryan Lee Jonathan Bautista Cynthia Rigsby Irene Helenowski Mahesh Gopalakrishnan 《Practical radiation oncology》2019,9(1):e62-e73