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991.
Eszter Scheiber O. Gabriel O. Hoffmann-Ostenhof J. J. Miller 《Monatshefte für Chemie / Chemical Monthly》1957,88(3):414-417
Ohne ZusammenfassungMit 3 Abbildungen 相似文献
992.
A spectrophotometric method for the determination of manganese in human plasma and red cells with benzohydroxamic acid is presented, Interfering ions are removed by an anion exchange method, using Dowex-1, 8X resin. The manganese concentration found for plasma and red cells was about 0.1 and 0.2 p.p.m , respectively. 相似文献
993.
Photooxidation of phenol, cresols, and dihydroxybenzenes 总被引:1,自引:0,他引:1
994.
995.
T. Brando I. Daftari A. Deguzman T.E. Kalogeropoulos R.A. Lewis D.I. Lowenstein R.J. Miller B.Y. Oh D.C. Peaslee C. Petridou M. Singer G.A. Smith G.S. Tzanakos R. Venugopal R.D. Von Lintig J. Whitmore 《Physics letters. [Part B]》1985,158(6):505-510
The p?p annihilation cross section has been measured with good resolution (~ 2 MeV RMS) in the mass range 1900–1960 MeV. No narrow structures are seen, the 90% confidence level upper limit being 8–12 mb MeV for the integrated area of a resonance in this mass range. However, we do not rule out a very narrow bump-dip structure seen in an earlier experiment in the 1935–1941 MeV mass interval. The data also do not support the existence of a broad structure previously reported at 1937 MeV. 相似文献
996.
997.
Sarah E London Yuichiro Itoh Valentin A Lance Petra M Wise Preethika S Ekanayake Randi K Oyama Arthur P Arnold Barney A Schlinger 《BMC neuroscience》2010,11(1):47
Background
Steroids affect many tissues, including the brain. In the zebra finch, the estrogenic steroid estradiol (E2) is especially effective at promoting growth of the neural circuit specialized for song. In this species, only the males sing and they have a much larger and more interconnected song circuit than females. Thus, it was surprising that the gene for 17β-hydroxysteroid dehydrogenase type 4 (HSD17B4), an enzyme that converts E2 to a less potent estrogen, had been mapped to the Z sex chromosome. As a consequence, it was likely that HSD17B4 was differentially expressed in males (ZZ) and females (ZW) because dosage compensation of Z chromosome genes is incomplete in birds. If a higher abundance of HSD17B4 mRNA in males than females was translated into functional enzyme in the brain, then contrary to expectation, males could produce less E2 in their brains than females. 相似文献998.
Background
Steroids are small molecule hormones derived from cholesterol. Steroids affect many tissues, including the brain. In the zebra finch, estrogenic steroids are particularly interesting because they masculinize the neural circuit that controls singing and their synthesis in the brain is modulated by experience. Here, we analyzed the zebra finch genome assembly to assess the content, conservation, and organization of genes that code for components of the estrogen-synthetic pathway and steroid nuclear receptors. Based on these analyses, we also investigated neural expression of a cholesterol transport protein gene in the context of song neurobiology. 相似文献999.
Marco Bisaglia Elisa Greggio Dragan Maric David W Miller Mark R Cookson Luigi Bubacco 《BMC neuroscience》2010,11(1):41
Background
Oxidative stress has been proposed to be involved in the pathogenesis of Parkinson's disease (PD). A plausible source of oxidative stress in nigral dopaminergic neurons is the redox reactions that specifically involve dopamine and produce various toxic molecules, i.e., free radicals and quinone species. α-Synuclein, a protein found in Lewy bodies characteristic of PD, is also thought to be involved in the pathogenesis of PD and point mutations and multiplications in the gene coding for α-synuclein have been found in familial forms of PD. 相似文献1000.
Chris Miller 《Proceedings of the American Mathematical Society》2006,134(5):1483-1493
Some necessary conditions are given on infinitely oscillating real functions and infinite discrete sets of real numbers so that first-order expansions of the field of real numbers by such functions or sets do not define . In particular, let be such that , as for some , is o-minimal, and the expansion of by the set does not define . Then there exist 0$"> and such that as .