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991.
Our study aimed to test the potential of Citrus oils in protecting against paracetamol (PAR)-induced hepatotoxicity. The essential oils of Pineapple sweet orange (OO), Murcott mandarin (MO), Red grapefruit (GO), and Oval kumquat (KO) were investigated using gas chromatography coupled with mass spectrometry (GC/MS). Twenty-seven compounds were identified, with monoterpene hydrocarbons being abundant class. d-Limonene had the highest percentage (92.98 %, 92.82 %, 89.75 %, and 94.46 % in OO, MO, GO, and KO, respectively). Hierarchical cluster analysis (HCA) and principal components analysis (PCA) revealed that octanal, linalool, germacrene D, and d-limonene were the principal discriminatory metabolites that segregated the samples into three distinct clusters. In vitro antioxidant capacities were ranged from 1.2–12.27, 1.79–5.91, and 235.05–585.28 μM Trolox eq/mg oil for 2,2′-azinobis(3-ethylbenzothiazoline-6-sulfonic (ABTS), ferric-reducing antioxidant power (FRAP), and oxygen radical absorbance capacity (ORAC), respectively. In vivo, citrus oils exhibited a significant reduction in alanine transaminase (ALT), aspartate transaminase (AST), alkaline phosphatase (ALP), and nitric oxide (NO). Additionally, there was an increase in glutathione reductase (GSH), and the liver architecture was nearly normal. Molecular docking revealed that d-limonene exhibited a good inhibitory interaction with cytochrome P450 (CYP450) isoforms 1A2, 3A4, and 2E1, with binding energies of −6.17, −4.51, and −5.61 kcal/mol, respectively.  相似文献   
992.
The availability of favorable genetic diversity is a thriving vitality for the success of a breeding program. It provides a firm basis of selecting superior breeding lines for the development of high yielding crop genotypes. In this context, present investigation aimed to generate information on genetic divergence and character association in a diversity panel of 123 local and exotic soybean genotypes. Analysis of variance revealed significant response of the evaluated genotypes based on studied attributes. It depicted the probability of selecting desirable soybean genotypes by focusing on character association studies and genetic diversity analysis. Correlation analysis revealed that seed yield per plant showed high positive correlation with 100-seed weight followed by pods per plant and plant height. Furthermore, path coefficient analysis exposed that pods per plant had maximum direct contribution in seed yield per plant followed by 100-seed weight, days to flowering and SPAD measurement. Genotype named “G-10” showed maximum yield per plant followed by 24607, G-52, 24593, Arisoy, 24566, 17426, A-3127, 24570 and 24567. Genetic diversity analysis grouped the evaluated germplasm into 17 clusters. All clusters showed zero intra-cluster variability; while inter-cluster divergence ranged from 9.00 to 91.11. Cluster V showed maximum inter-cluster distance with cluster XII followed by that of between V and VIII. Moreover, cluster IV with superior genotypes (G-10, 24607, 24593 and 24566), VI (17426 and 24567), XIII (24570) and X (Arisoy and G-52) showed above mean values for most of the studied characters. Overall, the results of hybridization between the superior genotypes of these cluster pairs might be useful for soybean breeding with improving agronomic traits and adaptability.  相似文献   
993.
The isolation of a thermophilic biosurfactant producing Bacillus SP   总被引:3,自引:0,他引:3  
Summary A thermophilic Bacillus strain has been isolated on a hydrocarbon containing medium and grew at up to 50°C. This strain produced biosurfactant and its 20h old culture broth had low surface and interfacial tension (27–29 and 1.5 mN/m, respectively). It emulsified Kerosene and other hydrocarbons efficiently (E–24 = 95 %) and was able to recover more than 95 % of the residual oil from sandpack columns. Potential uses in oil industries are discussed.  相似文献   
994.
Kuwaiti desert samples contaminated with crude oil contained Bacillus stearothermophilus strains capable of growth on crude oil as a sole source of carbon and energy, obligately at high temperature. No thermophilic oil utilizers were present in water samples collected from the Arabian Gulf. Most of the desert strains had an optimum temperature of 60°C and grew best on pentadecane (C15), hexadecane (C16) and heptadecane (C17). n-Alkanes with shorter and longer chains, n-alkenes, and aromatic hydrocarbons were less readily utilized. Correspondence to: N. A. Sorkhoh  相似文献   
995.
Abstract: We have studied the effect of long-term treatment with hydrocortisone on the expression of acetylcholine receptors (AChRs) at the neuromuscular junctions of human muscle cultured in monolayer and innervated de novo by fetal rat spinal cord motoneurons. Hydrocortisone increased accumulation of junctional AChRs in a dose-and time-dependent fashion. This increase was due to both decreased degradation and increased synthesis of AChRs. Other glucocorticoids, dexamethasone and prednisolone, exerted similar effects. Our study demonstrates a novel action of glucocorticoids on human junctional AChRs.  相似文献   
996.
Pollen beetles (Meligethes aeneus) are pests that feed and oviposit in the buds and flowers of oilseed rape. Honey-bees foraging from a hive fitted with an inoculum dispenser at the entrance effectively delivered dry conidia of the entomogenous fungus, Metarhizium anisopliae , to the flowers of oilseed rape in caged field plots. In both winter- and spring-sown rape experiments, a greater mortality of pollen beetles occurred in treated plots than in control plots. The mortality (61% on winter rape, 100% on spring rape) was greatest during peak flowering, when the feeding activity of both bees and beetles from the flowers was maximal, providing optimal conditions for inoculum dissemination and infection. Conidial sporulation occurred on a significant proportion of the dead pollen beetles. There was no evidence of any adverse effect on the honey-bee colonies.  相似文献   
997.
Pre- or post-treatment of duodenal discs with mannose, N-acetylglucosamine or chitin soluble extracts (CSE) prevented the adherence of Candida albicans to gastrointestinal tract. CSE was the most effective in blocking the adherence of C. albicans. Treatment of infant mice with saccharides significantly reduced the systemic spread of C. albicans inoculated into the gut. The best protection was obtained when the saccharides were given 2 days prior to the infection and continued over the course of the infection. However, systemic spread was reduced with a single dose of saccharide 30 min before infection. The saccharides may bind to the gastrointestinal mucosa and block the attachment of C. albicans.  相似文献   
998.
The cricothyroid muscle in dogs received branches from two independent nerves, namely the external ramus of the cranial laryngeal nerve and the pharyngeal branch of the vagus. Classical spindles are infrequent in the muscle. Atypical forms of sensory endings were identified. Two end-plates were frequently met with on a single extrafusal fibre. Sectioning of the external ramus of the cranial laryngeal nerve was followed by degeneration of spindles. Intact axons detected up to 6 months after operation are probably derived from the pharyngeal branch of the vagus. Chromatolytic changes occurred in the ipsilateral dorsal vagal nucleus and the capsulated ganglion at the entry of the nerve into the muscle. Chromatolysis occurred in the intramuscular ganglion cell rows and in neurons of the ipsilateral nodose ganglion. Morphological alterations were more pronounced in the ipsilateral medial column of the nucleus ambiguus. No changes were observed in the somata of the mesencephalic nucleus.  相似文献   
999.
Three variants of the chloramine-T radioiodination method were used to iodinate staphylococcal enterotoxin A with 125I. Only one method consistently produced usable labels for radioimmunoassay. The iodine incorporation was 55 to 76%; the specific activity was 3.5 to 5.5 muCi/microgram of enterotoxin, and the label was extremely stable on storage at -20 degrees C. Determinations of the enterotoxin in extracts of cheddar cheese produced without starter activity were carried out with the radioimmunoassay system and protein A as antibody immunoadsorbent. The assay buffer used in this system significantly influenced the detected levels of enterotoxin in the cheese extracts. Phosphate buffer, but not tris(hydroxymethyl)aminomethane (Tris) buffer, caused gelling of cheese extract proteins, thus resulting in an incomplete separation of free from antibody-bound 125I enterotoxin. When Tris buffer was used, the results indicated a high degree of accuracy and precision for this radioimmunoassay. The lowest detectable enterotoxin concentration in cheese extract was 0.5 ng/ml.  相似文献   
1000.
Ragai K. Ibrahim 《Phytochemistry》1980,19(11):2459-2460
A partially purified UDP-glucose: o-dihydroxycoumarin glucosyltransferase from tobacco cell culture required an intact coumarin ring system with o-dihydroxy groups for highest activity. The enzyme exhibited strict position specificity towards the 7-OH group of both esculetin and daphnetin with the formation of cichoriin and daphnin, respectively. The apparent Km values were 111 and 95 μM, while the Vmax for esculetin was 26.4 pkat/mg protein.  相似文献   
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