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81.
Timothy F. Wright & Melinda Dorin 《Ethology : formerly Zeitschrift fur Tierpsychologie》2001,107(2):111-124
Yellow-naped amazons, Amazona auropalliata , have regional dialects in which several functional classes of vocalization, including contact calls and pair duets, change their acoustic structure at the same geographic boundaries. Here we examine the responses of 11 pairs of yellow-naped amazons to playbacks of duets from other pairs nesting near the same roost, other roosts within the same dialect, and roosts in foreign dialect areas. Overall, pairs responded more strongly to duets from their own dialect than to those of the foreign dialect. Pairs responded to both treatments from their own dialect (local same dialect and distant same dialect) with movement towards the broadcasting loudspeaker and more rarely with squeals, a vocalization typically observed only in the context of aggressive chases. These aggressive responses were never observed during playbacks of the foreign dialect treatment or congeneric controls. There were no differences among treatments in the incidence of contact calls or pair duets. A similar pattern of stronger aggressive responses to local than to foreign dialects has been found in a wide range of oscine songbirds. The results of the present experiment suggest that a general function may underlie this behavioral response both in oscines and in other bird taxa with vocal learning. 相似文献
82.
Denonne F Binet S Burton M Collart P Defays S Dipesa A Eckert M Giannaras A Kumar S Levine B Nicolas JM Pasau P Pégurier C Preda D Van houtvin N Volosov A Zou D 《Bioorganic & medicinal chemistry letters》2007,17(12):3262-3265
The synthesis and structure-activity relationships against the C3a receptor of a series of substituted aminopiperidine derivatives are reported. DMPK properties and functional activities of selected compounds are described. The compounds obtained are the first non-arginine ligands of C3aR. 相似文献
83.
Ionuţ Grădianu Tomáš Přikryl Dorin Sorin Baciu Giorgio Carnevale 《Annales de Paléontologie》2019,105(1):75-83
A new pearleye species of the alepisauroid family Scopelarchidae, Scopelarchoides neamticus sp. nov., is described herein based on two specimens from the Oligocene Lower Dysodilic Shales Formation, cropping out in the Pietricica Mountain, Romanian Eastern Carpathians. The new species described herein exhibits a unique combination of features (including head length about 25% of SL; coracoid remarkably expanded; both preorbital and postorbital lengths larger than orbit diameter; 50 or 51 vertebrae; dorsal fin with nine or ten rays; anal-fin with 28 rays; length of anal fin base about 30% of SL; preanal distance almost 60% of SL; pelvic fin insertion located just under the second dorsal fin ray; pectoral fins only slightly longer than pelvic fins; caudal fin with 19 principal rays plus 14 upper and 13 lower procurrent rays) that justifies its recognition as a new species of the genus Scopelarchoides. Both morphological and meristic features suggest a certain degree of similarity between S. neamticus sp. nov. and the extant species Scopelarchoides signifer. The fossils of the new Oligocene species described herein represent the oldest known skeletal record of Scopelarchidae. 相似文献
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85.
A Daher M Longuet D Dorin F Bois E Segeral S Bannwarth P L Battisti D F Purcell R Benarous C Vaquero E F Meurs A Gatignol 《The Journal of biological chemistry》2001,276(36):33899-33905
Trans-activation response (TAR) RNA-binding protein (TRBP) is a cellular protein that binds to the human immunodeficiency virus-1 (HIV-1) TAR element RNA. It has two double-stranded RNA binding domains (dsRBDs), but only one is functional for TAR binding. TRBP interacts with the interferon-induced protein kinase R (PKR) and inhibits its activity. We used the yeast two-hybrid assay to map the interaction sites between the two proteins. We show that TRBP and PKR-N (178 first amino acids of PKR) interact with PKR wild type and inhibit the PKR-induced yeast growth defect in this assay. We characterized two independent PKR-binding sites in TRBP. These sites are located in each dsRBD in TRBP, indicating that PKR-TRBP interaction does not require the RNA binding activity present only in dsRBD2. TRBP and its fragments that interact with PKR reverse the PKR-induced suppression of HIV-1 long terminal repeat expression. In addition, TRBP activates the HIV-1 long terminal repeat expression to a larger extent than the addition of each domain. These data suggest that TRBP activates gene expression in PKR-dependent and PKR-independent manners. 相似文献
86.
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Hickman DT López-Deber MP Ndao DM Silva AB Nand D Pihlgren M Giriens V Madani R St-Pierre A Karastaneva H Nagel-Steger L Willbold D Riesner D Nicolau C Baldus M Pfeifer A Muhs A 《The Journal of biological chemistry》2011,286(16):13966-13976
Synthetic peptide immunogens that mimic the conformation of a target epitope of pathological relevance offer the possibility to precisely control the immune response specificity. Here, we performed conformational analyses using a panel of peptides in order to investigate the key parameters controlling their conformation upon integration into liposomal bilayers. These revealed that the peptide lipidation pattern, the lipid anchor chain length, and the liposome surface charge all significantly alter peptide conformation. Peptide aggregation could also be modulated post-liposome assembly by the addition of distinct small molecule β-sheet breakers. Immunization of both mice and monkeys with a model liposomal vaccine containing β-sheet aggregated lipopeptide (Palm1-15) induced polyclonal IgG antibodies that specifically recognized β-sheet multimers over monomer or non-pathological native protein. The rational design of liposome-bound peptide immunogens with defined conformation opens up the possibility to generate vaccines against a range of protein misfolding diseases, such as Alzheimer disease. 相似文献
88.
Zhang J Preda DV Vasquez KO Morin J Delaney J Bao B Percival MD Xu D McKay D Klimas M Bednar B Sur C Gao DZ Madden K Yared W Rajopadhye M Peterson JD 《American journal of physiology. Renal physiology》2012,303(4):F593-F603
The renin-angiotensin system (RAS) is well studied for its regulation of blood pressure and fluid homeostasis, as well as for increased activity associated with a variety of diseases and conditions, including cardiovascular disease, diabetes, and kidney disease. The enzyme renin cleaves angiotensinogen to form angiotensin I (ANG I), which is further cleaved by angiotensin-converting enzyme to produce ANG II. Although ANG II is the main effector molecule of the RAS, renin is the rate-limiting enzyme, thus playing a pivotal role in regulating RAS activity in hypertension and organ injury processes. Our objective was to develop a near-infrared fluorescent (NIRF) renin-imaging agent for noninvasive in vivo detection of renin activity as a measure of tissue RAS and in vitro plasma renin activity. We synthesized a renin-activatable agent, ReninSense 680 FAST (ReninSense), using a NIRF-quenched substrate derived from angiotensinogen that is cleaved specifically by purified mouse and rat renin enzymes to generate a fluorescent signal. This agent was assessed in vitro, in vivo, and ex vivo to detect and quantify increases in plasma and kidney renin activity in sodium-sensitive inbred C57BL/6 mice maintained on a low dietary sodium and diuretic regimen. Noninvasive in vivo fluorescence molecular tomographic imaging of the ReninSense signal in the kidney detected increased renin activity in the kidneys of hyperreninemic C57BL/6 mice. The agent also effectively detected renin activity in ex vivo kidneys, kidney tissue sections, and plasma samples. This approach could provide a new tool for assessing disorders linked to altered tissue and plasma renin activity and to monitor the efficacy of therapeutic treatments. 相似文献
89.
H. Straus M. Deleanu T. Frits E. Elges Angela Toader 《International journal of biometeorology》1968,12(3):241-249
Resume Les expériences ont porté sur des lapins repartis en deux groupes parallèles — un groupe étant traité avec des aéroions négatifs en concentrations moderées (n– = 10 – 40.000; n+ = 1.000) et l'autre sans aéroionothérapie (témoins). Par rapport aux animaux témoins (pas exposés aux aéroions),on a enregistré,sous l'influence de l'aéroionothérapie, que: (1)il y a une tendence de normalisation de la motilité spontanée, deprimée par une alimentation contenant un excès de cholestérol(0,3 g/kg/jour); (2) la lipémie et la cholestérolémie sont restées à un niveau plus bas chez les animaux alimentés au cholestérol; (3) la lipémie et la cholestérolémie, de même que l'iode thyroïdien, sont restées aux valeurs voisines de celles normales,chez les animaux nourris avec un excès (20 mg/kg/jour), de substances antithyroïdiennes naturelles (provenant du chou).
Groups of rabbits were exposed to negative air ions of moderate concentrations (n– = 10 – 40,000; n+ = 1,000) while others served as controls. (1) When rabbits were fed a cholesterol-rich diet (0.3 g/kg/day)causing reduction of motility in the control animals, their motility was normalized under air ion treatment. (2) The blood cholesterol and lipid levels of rabbits on a cholesterol-rich diet were lower with air ion treatment than in controls.(3) When rabbits were fed a diet with thyroid blocking agents from cabbage the blood cholesterol and lipid levels and the thyroid iodine content remained unchanged with air ion treatment.
Zusammenfassung Gruppen Kaninchen wurden mit negativen Luftionen in mässigen Konzentrationen (n– = 100 000 – 40 000; n+ = 1 000) behandelt, während andere als Kontrollen dienten. (1) Die durch Fütterung von cholesterinreicher Diät (0,3 g/kg/Tag) verminderte Motilität der Tiere wurde unter der Luftionenbehandlung normalisiert. (2) Der durch Fütterung von cholesterinreicher Diät erhöhte Blutcholesterin- und-fettspiegel fiel durch Luftionenbehandlung ab. (3) Der durch Fütterung von strumipriven Substanzen aus Kohl erhöhte Cholesterin- und Fettspiegel im Blut und verminderte Jodgehalt der Schilddrüse wurde durch Luftionenbehandlung nicht beeinflusst.相似文献
90.