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41.
A variety of analytical techniques was employed to study the composition of the chlamydospore of Candida albicans. The outer, thin, electron-transparent layer was found to be composed of glucan, together with a small amount of chitin. The inner, thick, electron-dense layer is proteinaceous. The central structure is composed largely of ribonucleic acid and lipid globules. In addition to being acid-fast, the chlamydospore was found to contain glycolipids and to lose the property of acid-fastness on extraction with ethanol-ether. 相似文献
42.
43.
Jason W. Skudlarek Christina N. DiMarco Kerim Babaoglu Anthony J. Roecker Joseph G. Bruno Mark A. Pausch Julie A. OBrien Tamara D. Cabalu Joanne Stevens Joseph Brunner Pamela L. Tannenbaum W. Peter Wuelfing Susan L. Garson Steven V. Fox Alan T. Savitz Charles M. Harrell Anthony L. Gotter Christopher J. Winrow Paul J. Coleman 《Bioorganic & medicinal chemistry letters》2017,27(6):1364-1370
In an ongoing effort to explore the use of orexin receptor antagonists for the treatment of insomnia, dual orexin receptor antagonists (DORAs) were structurally modified, resulting in compounds selective for the OX2R subtype and culminating in the discovery of 23, a highly potent, OX2R-selective molecule that exhibited a promising in vivo profile. Further structural modification led to an unexpected restoration of OX1R antagonism. Herein, these changes are discussed and a rationale for selectivity based on computational modeling is proposed. 相似文献
44.
Vilma Ortiz 《Ethnic and racial studies》2017,40(13):2240-2248
Bridging the divide between the ethnic/assimilation and the race literatures has long vexed sociologists. Valdez and Golash-Boza are to be commended for the intellectual effort they display in this article to engage this messy and contentious relationship. The distinction between the ethnic paradigm which produces assimilation projects and the racial paradigm which produces structural racism projects is important. I further this by noting that the process involved in the racial paradigm is racialization. I engage three examples: Mexican Americans, African-Americans, and white Americans. Together, these provide clarity to the discussion of how to pursue a unified approach. 相似文献
45.
Inga Cikotiene Egidijus Kazlauskas Jurgita Matuliene Vilma Michailoviene Jolanta Torresan Jelena Jachno Daumantas Matulis 《Bioorganic & medicinal chemistry letters》2009,19(4):1089-1092
A series of 5-aryl-4-(5-substituted-2,4-dihydroxyphenyl)-1,2,3-thiadiazoles were synthesized and their binding to several constructs of human Hsp90 chaperone measured by isothermal titration calorimetry (ITC). The most potent compound bound Hsp90 with the dissociation constant of about 5 nM. 相似文献
46.
Vilma Kisnierienė Vidmantas Sakalauskas Aleksandras Pleskačiauskas Vladimir Yurin Osvaldas Rukšėnas 《Central European Journal of Biology》2009,4(3):343-350
Interrelations between the action of acetylcholine (ACh) and cadmium ions (Cd2+) on bioelectrogenesis of Nitellopsis obtusa cells were investigated. We analyzed repetitively triggered action potentials (AP), their reproducibility, shape and dynamics
of membrane potential after AP induction. ACh significantly increased membrane permeability only at high concentrations (1
mM and 5 mM). Repolarisation level of action potential after the first stimulus was much more positive in all cells treated
with ACh as compared to the control. Differences of membrane potentials between points just before the first and the second
stimuli were 23.4±.0 mV (control); 40.4±5.9 mV (1 mM ACh solution) and 57.7 ± 8.5 mV (5 mM ACh solution). Cd2+ at 20 μM concentration was examined as a possible inhibitor of acetylcholinesterase (AChE) in vivo. We found that cadmium strengthens depolarizing effect of acetylcholine after the first stimulus. The highest velocity of
AP repolarization was reduced after ACh application and Cd2+strengthened this effect. There were no differences in dynamics of membrane potential after repetitively triggered action
potentials in ACh or ACh and Cd2+ solutions. This shows that cadmium in small concentration acts as inhibitor of acetylcholinesterase. 相似文献
47.
Vilma Kaškonienė Paulius Kaškonas Audrius Maruška Ona Ragažinskienė 《Acta Physiologiae Plantarum》2011,33(6):2377-2385
The variation in the content and composition of essential oils of Bidens tripartita L. grown in Lithuania has been studied using supercritical CO2 extraction followed by GC–MS. Extraction of essential oils was performed at two different pressures (9.1 and 15.1 MPa). Plant
material has been harvested at different phenological stages (from June to September). A total of 26 different compounds were
identified in the essential oils. The highest content and diversity of compounds was determined during the full-flowering
stage. Identified substances were mainly monoterpene hydrocarbons and sesquiterpene hydrocarbons. The main components were
α-pinene, p-cymene, trans-β-ocimene, and β-elemene. Chemometric analysis, including principal component and hierarchical cluster analyses, showed the
dependence of the essential oils qualitative as well as quantitative composition on the phenological stage the plant was collected
at. It also revealed that there was no correlation between age of the plant and quantity of the identified compounds. 相似文献
48.
Kozlowski JA Zhou G Tagat JR Lin SI McCombie SW Ruperto VB Duffy RA McQuade RA Crosby G Taylor LA Billard W Binch H Lachowicz JE 《Bioorganic & medicinal chemistry letters》2002,12(5):791-794
A novel series of 2-(R)-methyl-substituted piperazines (e.g., 2) is described. They are potent M(2) selective ligands that have >100-fold selectivity versus the M(1) receptor. In the rat microdialysis assay, compound 14 showed significantly enchanced levels of acetylcholine after oral administration. 相似文献
49.
Objectives
To assess HCV viremia levels just before, during and one year after anti-HCV seroconversion in people who inject drugs (PWID).Methods
PWID enrolling into a needle exchange program in Malmö, Sweden, 1997–2005 constituted the source population. Sera were obtained at enrolment and at approximately 3–4 monthly intervals afterwards, and were initially tested for anti-HIV, HBsAg/anti-HBc and anti-HCV and thereafter for markers previously negative. Seroconversion to anti-HCV had occurred during the study period in 186 out of 332 seronegative subjects. In these anti-HCV seroconverters, quantitative HCV RNA PCR was retrospectively performed on frozen sera to determine viremia levels in the last anti-HCV negative, the first anti-HCV positive and in one year follow-up samples.Results
Among 150 subjects seroconverting to anti-HCV with samples available from all three defined time-points, eight different patterns of viremia were observed. Spontaneous clearance at one year was noted in 48 cases (32%) and was associated with female gender (p = 0.03, CI 0.17–1.00). In 13 cases HCV-RNA was not detected in any study sample. Among 61 subjects with pre-seroconversion viremia, viral load was significantly higher in the pre-seroconversion samples compared to subsequent samples. For the whole group, viral load declined to undetectable levels at seroconversion in 28% of cases (but with recurrent viremia in 15%).Conclusions
Different patterns of HCV RNA kinetics were observed among PWID with documented seroconversion to anti-HCV. The frequently observed absence of detectable HCV RNA in the first anti-HCV positive sample (irrespective of subsequent viremia) demonstrates the importance of repeated sampling and RNA testing for determination of the outcome of acute infection. 相似文献50.
Janina Petkeviciene Jurate Klumbiene Sandrita Simonyte Indre Ceponiene Kristina Jureniene Vilma Kriaucioniene Asta Raskiliene Alina Smalinskiene Vaiva Lesauskaite 《PloS one》2014,9(10)