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911.
Al-Ja'fari AH Vila R Freixa B Tomi F Casanova J Costa J Cañigueral S 《Phytochemistry》2011,72(11-12):1406-1413
The analysis of the essential oil from rhizome and roots of Ferula hermonis Boiss. (Apiaceae) by GC-FID, GC-MS and 13C NMR allowed the identification of 79 constituents, more than 90% of the oil, the major one being α-pinene (43.3%), followed by α-bisabolol (11.1%) and the unusual acetylenic compound 3,5-nonadiyne (4.4%). The antifungal activity of the essential oil before and after fractionation was assayed against several yeasts and filamentous fungi. Purification of the active fractions afforded 3,5-nonadiyne, α-bisabolol, jaeschkeanadiol angelate, α-bisabolol oxide B and trans-verbenol, as well as two purified fractions, one of them (JB73) with 73% of jaeschkeanadiol benzoate and the other with 50% of spathulenol. Determination of MIC and MFC values of all these products evidenced strong antifungal activities for JB73 and 3,5-nonadiyne. Particularly, against the dermatophyte Tricophyton mentagrophytes, MIC and MFC values were 0.25 μg/ml for JB73, and 8 μg/ml for 3,5-nonadiyne, the former being more active than amphotericin B and nystatin. 相似文献
912.
Coloma MA Toledano-Díaz A Castaño C Velázquez R Gómez-Brunet A López-Sebastián A Santiago-Moreno J 《Theriogenology》2011,76(9):1695-1705
The present work examines the relationship between seasonal changes in testicular function, accessory gland size, and horn growth in Iberian ibexes, as well as the relationship between these changes and the resistance of ibex spermatozoa to freezing-thawing. The size of the bulbourethral glands and seminal vesicles showed pronounced monthly variation (P < 0.001), which was correlated positively with the plasma testosterone concentration (P < 0.001) and scrotal circumference (P < 0.001). The size of the accessory sex glands peaked during the autumn. Overall, semen quality was markedly improved during autumn and winter. When horn growth was at a minimum during autumn and winter, semen quality and accessory gland size were all increased compared to in spring and summer. However, increased plasma testosterone levels in the autumn were strongly associated with reduced sperm freezability; thus, the cryosurvival of spermatozoa collected during the autumn was poorer than at other times of the year. In winter, however, when the plasma testosterone concentration fell to baseline, the negative effects of cryopreservation on the percentage of motile spermatozoa and on the integrity of the plasma membrane of frozen-thawed sperm cells were significantly less intense (P < 0.05). These findings show a clear relationship between the functional and morphological status of the different parts of the reproductive tract that optimises reproductive function during the breeding season in the ibex male. They also show that winter is the most suitable season for the collection and cryopreservation of ibex spermatozoa. 相似文献
913.
Sánchez R Velásquez J Navarro A 《Biomédica : revista del Instituto Nacional de Salud》2011,31(3):410-418
Introduction. The Mania Scale (EMUN) developed at the Universidad Nacional de Colombia was designed to measure the severity of manic symptoms, but has been validated only using classical psychometric theory. Objectives. The psychometric properties and measuring characteristics of the EMUN scale were determined using an analysis based on item response theory. Materials and methods. Two hundred sixty-four patients with manic, hypomanic or mixed episode symptoms were assessed using the EMUN scale. The psychometric characteristics of the scale were analyzed using a Rasch model for partial credit scoring. Results. The analysis based on the item response theory showed that reliability and separation indexes for persons are low in contrast to items. This suggested a narrow representation of the construct evaluated in this sample. Reduced need to sleep has been the most easily detectable symptom in mania. Excepting depressive affect and distractibility, the majority of items fit the model?s expectation The rating scale diagnostics showed that the average measures increase monotonically across the rating scale. Two items showed redundancy and can be omitted in future versions of the scale. The person-item map suggested that the syndrome is not fully evaluated by the scale, probably because some depressive symptoms are not included. Conclusion. In this first study to use Rasch analysis to assess the psychometric properties of the EMUN scale, misfit and redundancy of items have been detected. The manic syndrome is not fully evaluated by the scale. The instrument can be improved by adding depressive symptoms. 相似文献
914.
915.
The combined use of stable carbon and oxygen isotopes in plant matter is a tool of growing interest in cereal crop management and breeding, owing to its relevance for assessing the photosynthetic and transpirative performance under different growing conditions including water and N regimes. However, this method has not been applied to wheat grown under real field conditions. Here, plant growth, grain yield (GY) and the associated agronomic components, carbon isotope discrimination (Δ13C) plus oxygen isotope composition (δ18O) as well as leaf and canopy gas exchange were measured in field‐grown wheat subjected to different water and N availabilities. Water limitation was the main factor affecting yield, leaf and canopy gas exchange and Δ13C and δ18O, whereas N had a smaller effect on such traits. The combination of Δ13C and δ18O gave a clear advantage compared with gas exchange measurements, as it provides information on the instantaneous and the long‐term plant photosynthetic and transpirative performance and are less labour intensive than gas exchange measurements. In addition, the combination of plant Δ13C and δ18O predicted differences in GY and related agronomical parameters, providing agronomists and breeders with integrative traits for selecting crop management practices and/or genotypes with better performance under water‐limiting and N‐limiting conditions. 相似文献
916.
917.
We developed an atomic force microscopy (AFM) method to determine the binding forces between a model cell wall plasma membrane and Vibrio cholerae. V. cholerae cells were covalently attached to AFM probes and forces were determined against a lipid bilayer containing sialic acid (N-acetylneuraminic acid) molecules as well as several control surfaces. 相似文献
918.
919.
Ventura S 《Journal of biomolecular structure & dynamics》2011,28(4):655-6; discussion 669-674
920.
Abdellatif KR Velázquez CA Huang Z Chowdhury MA Knaus EE 《Bioorganic & medicinal chemistry letters》2011,21(4):1195-1198
A group of (Z)-1,2-diphenyl-1-[4-[2-(4-methylpiperazin-1-yl)ethoxy]phenyl]but-1-enes were synthesized using methodologies that will allow incorporation of a [124I]iodine substituent at the para-position of either the C-1 phenyl ring or the C-2 phenyl ring, or a [18F]OCH2CH2F substituent at the para-position of the C-2 phenyl ring. These [124I] and [18F] radiotracers are designed as potential radiopharmaceuticals to image estrogen positive breast tumors using positron emission tomography (PET). 相似文献