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231.
Zusammenfassung Zellkerne, die aus Kaninchengewebe mittels eines nichtwässrigen Verfahrens bereitet werden, enthalten in ihren säurelöslichen Bestandteilen Nukleotide von Adenin, Hypoxanthin, Guanin, Uracil und (in sehr geringen Mengen) von Cytosin. Diese Stoffe wurden in Lunge, Darm-Mucosa, Knochenmark, Appendix und Thymus in abnehmender Konzentration vorgefunden.
British Empire Cancer Campaign Research Fellow 相似文献
British Empire Cancer Campaign Research Fellow 相似文献
232.
DNA-directed DNA polymerase activity in oncogenic RNA viruses 总被引:34,自引:0,他引:34
S Spiegelman A Burny M R Das J Keydar J Schlom M Travnicek K Watson 《Nature》1970,227(5262):1029-1031
233.
In vitro studies showed that the flavonoid aglycones apigenin, luteolin and kaempferol inhibited the hyaluronidase activity of five different venoms dose-dependently. They were also able to delay the venom action when injected into mice. Naringenin, catechin and flavonoid glycosides had no effect. The flavonoids with unsubstituted hydroxyl groups at C-positions 5, 7 and 4′, a double bond between carbons 2 and 3, as well as a ketone group at position 4, exhibited potent inhibitory actions on the venom hyaluronidases. 相似文献
234.
Mutations in LGI1 cause autosomal-dominant partial epilepsy with auditory features. 总被引:28,自引:0,他引:28
Sergey Kalachikov Oleg Evgrafov Barbara Ross Melodie Winawer Christie Barker-Cummings Filippo Martinelli Boneschi Chang Choi Pavel Morozov Kamna Das Elita Teplitskaya Andrew Yu Eftihia Cayanis Graciela Penchaszadeh Andreas H Kottmann Timothy A Pedley W Allen Hauser Ruth Ottman T Conrad Gilliam 《Nature genetics》2002,30(3):335-341
The epilepsies are a common, clinically heterogeneous group of disorders defined by recurrent unprovoked seizures. Here we describe identification of the causative gene in autosomal-dominant partial epilepsy with auditory features (ADPEAF, MIM 600512), a rare form of idiopathic lateral temporal lobe epilepsy characterized by partial seizures with auditory disturbances. We constructed a complete, 4.2-Mb physical map across the genetically implicated disease-gene region, identified 28 putative genes (Fig. 1) and resequenced all or part of 21 genes before identifying presumptive mutations in one copy of the leucine-rich, glioma-inactivated 1 gene (LGI1) in each of five families with ADPEAF. Previous studies have indicated that loss of both copies of LGI1 promotes glial tumor progression. We show that the expression pattern of mouse Lgi1 is predominantly neuronal and is consistent with the anatomic regions involved in temporal lobe epilepsy. Discovery of LGI1 as a cause of ADPEAF suggests new avenues for research on pathogenic mechanisms of idiopathic epilepsies. 相似文献
235.
Summary The free enrgies of transfer (G
t
0
) of H+, Cl–, Br–, I– and SCN– ions from water to 10, 20, 30 and 40% dioxanewater mixtures have been studied from potentiometric measurements. For anions the G
t
0
values are in the order Cl–>Br–>SCN–>I–. 相似文献
236.
Summary The free energy of transfer ( G
t
0
) of KBrO3 and KIO3 from water to 10, 20 and 30% dioxane-water mixtures have been studied from conductometric measurements. The G
t
0
values are in the order of BrO
3
–
>IO
3
–
. 相似文献
237.
Cu–graphene (Gr) composite thin films were prepared by electrodeposition route using in-house synthesized Gr sheets. The Gr sheets were synthesized by the electrochemical exfoliation route using 1 M HClO4 acid as electrolyte. The Gr sheets were confirmed by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), field-emission scanning electron microscopy (FESEM), and transmission electron microscopy (TEM). The (002) plane of Gr sheets was observed at 2θ of 25.66°. The (002) plane confirmed the crystal structure of carbon peaks. The stretching vibration of C=C bond at a wavelength of 1577 cm?1 and other functional groups of carboxyl and epoxide groups were observed from FTIR. TEM confirmed the transparent structure of Gr sheets. The prepared Gr sheets were used as reinforcement at concentrations of 0.1 and 0.3 g/L with a copper matrix to synthesize the Cu–Gr composite. The prepared composite thin films were characterized by XRD, SEM, and energy-dispersion spectrometry (EDS) for morphological and analytical studies. The presence of Gr sheets in Cu–Gr composite was confirmed by EDS analysis. The prepared Cu–Gr nanocomposite thin film showed higher corrosion resistance compared with pure copper thin films in 3.5wt% NaCl, as confirmed by Tafel plots. Electrochemical impedance spectroscopy complimented the above results and showed that 0.3 g/L composite film achieved the highest film resistance. 相似文献
238.
A candidate spermatogenesis gene on the mouse Y chromosome is homologous to ubiquitin-activating enzyme E1. 总被引:17,自引:0,他引:17
The human X-linked gene A1S9 complements a temperature-sensitive cell-cycle mutation in mouse L cells, and encodes the ubiquitin-activating enzyme E1. The gene has been reported to escape X-chromosome inactivation, but there is some conflicting evidence. We have isolated part of the mouse A1s9 gene, mapped it to the proximal portion of the X chromosome and shown that it undergoes normal X-inactivation. We also detected two copies of the gene on the short arm of the mouse Y chromosome (A1s9Y-1 and A1s9Y-2). The functional A1s9Y gene (A1s9Y-1) is expressed in testis and is lost in the deletion mutant Sxrb. Therefore A1s9Y-1 is a candidate for the spermatogenesis gene, Spy, which maps to this region. A1s9X is similar to the Zfx gene in undergoing X-inactivation, yet having homologous sequences on the short arm of the Y chromosome, which are expressed in the testis. These Y-linked genes may form part of a coregulated group of genes which function during spermatogenesis. 相似文献
239.
The polyunsaturated fatty acids (PUFAs), linoleic acid (LA), alpha linolenic acid (ALA), gamma linolenic acid (GLA), arachidonic acid (AA), docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA), showed inhibition of growth of both normal and abnormal (Molt-4) human lymphocytes, and inhibition was concentration-dependent. Interestingly, the production of the lymphokine Interleukin-2 (IL-2) was elevated in Molt-4 cells, but it was reduced in the normal human lymphocytes. Addition of GLA or IL-2 or a combination of both showed enhancement of SO
2
–
and of lipid peroxidation levels, which were significantly higher in Molt-4 cells than in the normal lymphocytes. Reduction of protein concentration was also observed in both types of cells during this treatment. The data showed that the antiproliferative effects of GLA and IL-2 may partly be exerted through the elevated production of superoxide free radicals and peroxidatin products. This is a novel finding and therefore, further exploitation of combinations of PUFAs and IL-2 may be a possible way of combating cancer cell growth. 相似文献
240.
Summary
Streptomyces species 3M grew in peptone yeast extract medium with 1000 g/ml K2Cr2O7. Incubation of the chromate with different cell fractions in the presence of NADH and NADPH resulted in a decrease of Cr6+ in the reaction mixture. The level of Cr6+ was reduced by 82.7% by a particulate cell fraction obtained by centrifugation at 105,000×g for 1 h, in the presence of NADH. The reducing enzyme was associated with this cell fraction. The enzyme was constitutive and reduced Cr6+ to Cr3+. 相似文献