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821.
822.
We investigated the impact of sexual stimuli and the influence of sexual motivation on the performance in a dot-probe task and a line-orientation task in a large sample of males and females. All pictures (neutral, erotic) were rated on the dimensions of valence, arousal, disgust, and sexual arousal. Additionally, questionnaires measuring sexual interest/desire/motivation were employed. The ratings of the sexual stimuli point to a successful picture selection because sexual arousal did not differ between the sexes. The stimuli were equally arousing for men and women. Higher scores in the employed questionnaires measuring sexual interest/desire/motivation led to higher sexual arousal ratings of the sex pictures. Attentional bias towards sex pictures was observed in both experimental tasks. The attentional biases measured by the dot-probe and the line-orientation task were moderately intercorrelated suggesting attentional bias as a possible marker for a sex-attention trait. Finally, only the sexual sensation seeking score correlated with the attentional biases of the two tasks. Future research is needed to increase the predictive power of these indirect measures of sexual interest. 相似文献
823.
824.
Abstract Streptomyces antibioticus strain TÜ 99, from which a wide variety of active compounds had been isolated previously, was reinvestigated using an HPLC photoconductivity screening system. Four new compounds were isolated, characterized and their constitutions determined. All four were α,β-unsaturated γ-lactones; the most abundant compound 3 (C10 H16 O4 ), as well as compound 1 (C9 H14 O4 ) had a hydroxy group at C(5) of the lactone ring. The four lactones showed antibiotic activity against Pseudomonas aeruginosa and also a weak inhibition of the chitinase from Serratia marcescens . 相似文献
825.
Rina Rosin-Arbesfeldb Pnina Mashiah Dieter Willbold Paul Rosch Steven R. Tronick Abraham Yaniv Arnona Gazit 《Gene》1994,150(2):307-311
The Tat protein of equine infectious anemia virus (EIAV) was synthesized in Escherichia coli using the inducible expression plasmid, pET16b, which contains a His.Tag leader, thus allowing for rapid and efficient enrichment of the histidine-tagged protein by metal affinity chromatography. Yields of up to 20 mg of Tat were obtained from 1011 bacterial cells. The recombinant Tat protein was shown to potently trans-activate the EIAV long terminal repeat (LTR) following its introduction into canine cells by ‘scrape loading’. The EIAV Tat protein was found to localize predominantly within the cytoplasm, in contrast to HIV-1 Tat. The availability of large amounts of purified functional EIAV Tat protein should greatly facilitate detailed structure-function analyses. 相似文献
826.
827.
The title compound crystallizes rhombohedrally in the space group R3 with a = 20.453(11) and c = 4.197(1) Å (hexagonal setting). The structure was refined by full matrix lest squares with 585 independent reflections to R equal 0.042 (Rw = 0.040). Antimony, situated on the threefold axis, is pyramidally coordinated at 2.493(3) Å to the sulfur atoms of the three ligands. Secondary bonding occurs at 2.802(8) Å to the oxygen atoms of the asymmetrically chelating ligands. 相似文献
828.
Protein preparations from seeds and seedlings (cotyledons) of rape (Brassica napus subsp. napus [L.] DC.) catalyzed the transfer of sinapic acid from 1-Osinapoyl--glucose to malate in the formation of O-s-inapoylmalate. The enzyme involved, 1-O-sinapoyl--glucose: l-malate O-sinapoyltransferase (SMT; EC 2.3.1), catalyzes the key step in the overall conversion of the seed constituent sinapine (O-sinapoylcholine) to the accumulating O-sinapoylmalate by way of the intermediate 1-O-sinapoyl--glucose. The present paper describes this phenomenon focussing on SMT activity.Abbreviations Sin-Glc
1-O-sinapoyl--glucose
- Sin-Mal
O-sinapoylmalate
- SMT
1-O-sinapoyl--glucose: l-malate sinapoyltransferase (EC 2.3.1)
This work was supported by the Deutsche Forschungsgemeinschaft, the Fonds der Chemischen Industrie and the Ontario Ministry of Agriculture and Food. 相似文献
829.
The Effect of Protonation and Electrical Interactions on the Stereochemistry of Retinal Schiff Bases 总被引:2,自引:1,他引:1
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Based on quantumchemical MNDOC calculations it is shown that the ground-state properties of a retinal Schiff base depend sensitively on its protonation state and charge environment. This is exemplified for the equilibrium geometry, for the distribution of partial charges and, in particular, for the thermal isomerization barriers around the π-bonds. It is demonstrated that a protein, by protonating the retinal Schiff base and by providing one or two negative ions in its environment, can reduce double-bond isomerization barriers from 50 kcal/mol for the unprotonated compound to ~ 5 kcal/mol and can increase single bond barriers from 5 kcal/mol to ~ 20 kcal/mol. Thereby, the specific location of the ions relative to the polyene chain of the protonated retinal Schiff base determines the barrier heights. The results explain the ground-state isomerization reactions of retinal observed in bacteriorhodopsin and in squid retinochrome. 相似文献
830.
Dieter C. Wasshausen 《Brittonia》1985,37(2):203-208
New species of Hansteinia (Acanthacene) from Columbia and Equador, Brittonia 37: 203-208. 1985. – Two new species and a new variety, Hansteinia jamesonaii from Pichincha, Equador and H. Magdalensis and H. magdalenensis var. pilosa from the Sierra Nevada de Sta. Marta, are described, illustrated, and compared with H. charitopes their closest relative. 相似文献