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The dopamine metabolite, homovanillic acid, decreases in concentration in plasma between 8:30 A.M. and 12:30 P.M. In patients with schizophrenia this cyclic change is attenuated by chronic neuroleptic treatment; however, if the 8 A.M. dose of neuroleptic is omitted, the decrease in level occurs. Presuming that neuroleptics attenuate the decline through a receptor mediated compensatory increase in dopamine release, it would appear that receptors are not fully occupied by neuroleptics even at therapeutically effective doses. The usual morning decrease in plasma cortisol levels was unaffected by neuroleptics. 相似文献
95.
The study of water relaxation rates of solutions of melanins with paramagnetic metal ions provides a powerful tool for investigating the binding sites and for obtaining useful structural and dynamic information. The measure of 1H- and 2H-longitudinal and transverse relaxation rates at a single, high-magnetic field for H2O/D2O (80:20) solutions allows the determination of tau c, tau R, tau e, tau M, r, q, and Z (the outer sphere contribution to the overall relaxation rate) for Mn(II)-L-Dopa melanin system. 相似文献
96.
A A Grinev E I Samokhvalov N A Petrov S K Vasilenko V P Iuferov 《Molekuliarnaia genetika, mikrobiologiia i virusologiia》1988,(9):43-45
The primary structure of hemagglutinin (HA) gene of Influenza virus A/USSR/90/77 (H1N1) variants after 3 and 11 passages has been determined. In the HA1 coding region of mice-adapted virus (11 passages) there are two amino acid substitutions: Thr 89----Ala and Asn 127----Asp. At the first stage of adaptation (3-rd passage) only a single mutation was detected: Asn 127----Asp. The adaptation is accompanied by the loss of specific carbohydrate attachment sites adjacent to the receptor-binding site located at HA1 subunit with a concomitant variation in antigenicity. 相似文献
97.
Bharat Lagu John M. Wetzel Carlos Forray Michael A. Patane Mark G. Bock 《Bioorganic & medicinal chemistry letters》2000,10(24)
The binding affinities and selectivities of antagonists Figure 1 and Scheme 2 for the α1A-adrenoceptor are dependent on the stereochemical orientation of the groups at the C-4 and C-5 positions of the oxazolidinone ring. The unambiguous assignment of the relative and absolute configurations of the diastereomers of SNAP 7915 (Figure 1 and Scheme 2) is reported. 相似文献
98.
T. A. Misharina M. B. Terenina N. I. Krikunova I. A. Khankhalaeva I. S. Khamagaeva L. L. Nikiforova 《Applied Biochemistry and Microbiology》2008,44(5):545-550
The differences between the composition of volatile substances in two specimens of dry smoked sausages produced using a standard and experimental (a mixture of propionic acid bacteria and bifidobacteria) cultures were studied by capillary gas chromatography. It was found that the experimental starter culture intensified the flavor-formation processes as compared with the standard culture. The experimental specimen had richer qualitative and quantitative compositions and displayed more intensive aroma and flavor. The contents of lactones and volatile terpenoids in the experimental specimen were much higher than in the control. The organoleptic characteristics of experimental dry smoked sausage specimen were considerably better. 相似文献
99.
The dynamics of the sympathoadrenal function and the specific features of heart rhythm regulation were studied in female students and clothing factory female workers during their adaptation to academic and work conditions. Periods of the strongest functional tension in test systems were found in first-year students: the beginning of an academic year, the end of the first semester, and a period after winter examinations, all characterized by an increase in the central-circuit and sympathetic effects on sinus rhythm, acceleration of the heart rate, activation of sympathoadrenal mechanisms, and a decrease in sympathoadrenal reserves. The comparative analysis allowed us to disclose general trends typical of females of this age group such as the relative maturity of the sympathoadrenal system (SAS) and optimum correlation between autonomic and centralized heart rhythm regulation and to reveal the differences in the character and dynamics of functional shifts caused by a specific effect of academic load and work conditions. The degree of correlation between the indices characteristic of hormonal and mediator SAS mechanisms and the statistical characteristics of heart rhythm was proposed as the criteria for estimating the functional tension of the human body. 相似文献
100.
R. L. Orozco M. D. Redwood P. Yong I. Caldelari F. Sargent L. E. Macaskie 《Biotechnology letters》2010,32(12):1837-1845
Escherichia coli strains MC4100 (parent) and a mutant strain derived from this (IC007) were evaluated for their ability to produce H2 and organic acids (OAs) via fermentation. Following growth, each strain was coated with Pd(0) via bioreduction of Pd(II).
Dried, sintered Pd-biomaterials (‘Bio-Pd’) were tested as anodes in a proton exchange membrane (PEM) fuel cell for their ability
to generate electricity from H2. Both strains produced hydrogen and OAs but ‘palladised’ cells of strain IC007 (Bio-PdIC007) produced ~threefold more power as compared to Bio-PdMC4100 (56 and 18 mW respectively). The power output used, for comparison, commercial Pd(0) powder and Bio-Pd made from Desulfovibrio desulfuricans, was ~100 mW. The implications of these findings for an integrated energy generating process are discussed. 相似文献