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741.
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743.
Chromatin-mediated regulation of flowering time in Arabidopsis 总被引:1,自引:0,他引:1
744.
K Shizume Y Shishiba K Kuma S Noguchi J Tajiri K Ito J Y Noh 《Endocrinologia japonica》1992,39(3):315-318
Periodic paralysis has been known to be associated with thyrotoxicosis in Japan. The incidence was 8.6% among male and 0.4% among female thyrotoxic patients according to a survey performed in the three major thyroid clinics in Japan in 1957. To determine the changes in the incidence during the intervening 34 years, the same type of survey was carried out again in 1991 at the same three major thyroid clinics previously involved. The incidence of paralysis in 1991 was 4.3% among male and 0.04% among female thyrotoxic patients, indicating more than a 40% decrease in the incidence. The possible cause of the decrease is related to the changes in food consumption, namely, to the fact that less carbohydrate and more potassium were taken in 1991 than in 1957. 相似文献
745.
Estimation of lipase activity by the diffusion plate method 总被引:2,自引:0,他引:2
J. Karnetová J. Matějů T. Řezanka P. Procházka M. Nohýnek J. Rokos 《Folia microbiologica》1984,29(4):346-347
A diffusion plate method for the assay of the activity of lipases in large series of samples was worked out. When using this
method the maximum deviation was found to be ±3.8%. 相似文献
746.
In addition to typical acetyl esters, acetic ester aoetyl-hydrolase fromMycobacterium phlei can degrade aliphatic acetylated amino acids under suitable conditions. 相似文献
747.
We investigated the functional organization of the human auditory cortex using a novel electrophysiological recording technique
combined with an advanced brain magnetic resonance imaging (MRI) technique. Tonotopic mapping data were obtained during single
unit recording along the Heschl’s gyrus. Most of the units studied (73%) demonstrated sharply tuned excitatory responses.
A tonotopic pattern was observed with the best frequencies systematically increasing as more medial-caudal recording sites
were sampled. Additionally, a new auditory field along the posterior aspect of the superior temporal gyrus has been identified
using a high spatial resolution direct recording technique. Results obtained during electrical stimulation demonstrate functional
connectivity between the primary auditory cortex and the auditory field in the posterior superior temporal gyrus. 相似文献
748.
The interaction of the carcinogenic mycotoxin, aflatoxin B1, with some electrondonating organic compounds including aromatic hydrocarbons, dimethylaniline, and aromatic amino acids, was studied. Spectrophotometric analysis of aflatoxin B1 revealed that hypochromicity in the absorption around 360 nm and hyperchromicity around 385 nm were induced by dimethylaniline, hexamethylbenzene, tryptophan, and imidazole. A similar shifting of aflatoxin B1 absorption was observed in benzene, toluene, and xylene in the presence of ZnCl2. The interaction of aflatoxin B1 with polystyrene was observed in a biphasic system. The association constants of aflatoxin B1: DMA4 (1:1) and of aflatoxin B1: tryptophan (1:1) were found to be 0.64 and 22.6 liters per mole, respectively. The results suggest that charge-transfer interaction occurs between aflatoxin B1 and these π-electron donors. Since the spectral changes on aflatoxin B1 absorption induced by these π-electron donors are similar to those induced by nucleic acids and proteins, it is postulated that charge-transfer interaction also occurs between aflatoxin B1 and these macromolecules. The role of such interaction in the biological activity of aflatoxin B1 is discussed. 相似文献
749.