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951.
952.
Yanase T Imai T Simpson ER Waterman MR 《The Journal of steroid biochemistry and molecular biology》1992,43(8):973-979
17α-Hydroxylase deficiency is characterized by a defect in either or both of 17α-hydroxylase and 17,20-lyase activities, based on the fact that a single polypeptide P450c17 can catalyze both reactions. The clinical manifestations of 17α-hydroxylase/17,20-lyase deficiency seem to be more heterogeneous than expected, varying from the classical type to less symptomatic forms as also observed in 21-hydroxylase deficiency. We have sequenced all eight exons of the CYP17 (P450c17) gene in DNA from several patients, reconstructed the mutations in a human P450c17 cDNA and expressed the mutant P450c17 in COS 1 cells to characterize the kinetic properties of 17α-hydroxylase and 17,20-lyase activities. The molecular bases of cases clinically reported as 17α-hydroxylase deficiency have turned out to be complete or partial combined deficiencies of 17α-hydroxylase/17,20-lyase. The elucidation of the molecular basis generally explains the patient's clinical profiles including the sexual phenotype of the external genitalia. In one case clinically reported as isolated 17,20-lyase deficiency, the molecular basis was found to be partial combined deficiency of both activities, somewhat discordant with the patient's clinical profile. Based on the results obtained so far we can predict that those 17α-hydroxylase deficient individuals having a homozygous stop codon in the CYP17 gene positioned at the amino terminal side of the P450c17 heme-binding cysteine (442) will all have the same phenotype. However those individuals having homozygous missense mutations or those who are compound heterozygotes having a missense mutation in at least one CYP17 allele will display their own unique phenotype which clinically will be subtly different from all others. 相似文献
953.
954.
Sigma region located between C mu and C delta genes of human immunoglobulin heavy chain: possible involvement of tRNA-like structure in RNA splicing. 总被引:8,自引:5,他引:3
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![点击此处可从《Nucleic acids research》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Y Akahori H Handa K Imai M Abe K Kameyama M Hibiya H Yasui K Okamura M Naito H Matsuoka 《Nucleic acids research》1988,16(20):9497-9511
955.
Y Saito T Imai N Nagamoto M Sato S Ota K Kanma S Takahashi K Usuda M Sagawa H Suda 《Analytical and quantitative cytology and histology / the International Academy of Cytology [and] American Society of Cytology》1988,10(5):365-370
The abnormal cells (atypical squamous cells and cancer cells) in the sputum of 12 in situ and 20 early invasive squamous cell carcinomas were studied quantitatively and compared with the cells in 12 borderline cases and 11 frankly invasive squamous cell carcinomas, In in situ and early invasive squamous cell carcinomas, the mean nuclear diameters were larger and multinucleated cells and distinct nucleoli were more frequent than in borderline cases. Furthermore, the mean cellular diameters and the number of abnormal cells per slide were smaller, the distinct nucleoli were less frequent and acidophilic cytoplasms were more frequent than in frankly invasive squamous cell carcinomas. The results indicate that (1) in situ and early invasive squamous cell carcinomas are generally distinguishable cytologically from borderline cases and from frankly invasive squamous cell carcinomas and (2) the cytologic differentiation between in situ and early invasive squamous cell carcinomas is quantitatively insufficient. 相似文献
956.
Large numbers of spontaneously occurring polypoid or slightly elevated lesions were observed in the tongue, mainly the dorsum linguae near the margo linguae, of DBA mice. Histologically the lesion consisted of granulation tissue with focal calcification, and involved superficially the tongue muscle. Often the calcareous deposits were encircled by multinuclear giant cells. The frequency of the calcified tongue lesion was high in lines of DBA/2 (DBA/2NCrj, DBA/2NJcl and DBA/2J), and DBA/1 (DBA/1Jcl and DBA/1J); the SM/J, BALB/c, C57BL/6 and C3H/He strains did not have the lesion. Among hybrid mice, CDF1, a hybrid of DBA/2 and BALB/c, a few had the lesions but no BDF1 mice, a hybrid of DBA/2 and C57BL/6, had any. The frequency was high in the hybrids of DBA/1 and SM/J. These results seem to indicate that the occurrence of the tongue calcified lesions was controlled by polygene. 相似文献
957.
Toshimi Matsuno Nobuo Kobayashi Fumio Hariguchi Toshiyuki Yamazaki Kin-ichi Imai Hiroshi Onaga 《Experimental parasitology》1984,57(1):55-61
The anticoccidial activity of an orotic acid analog, 1,6-dihydro-6-oxo-2-pyrazinecarboxylic acid 4-oxide (carboxyemimycin), was tested in battery experiments, utilizing 9-day-old Single-Comb White Leghorn cockerels. Carboxyemimycin, at 125 ppm and more in feed, exhibited marked anticoccidial activities against Eimeria tenella, E. necatrix, E. acervulina, and E. maxima. High doses of carboxyemimycin—up to 1000 ppm—did not cause any reduction in weight gains. The battery and in vitro studies with delayed and restricted medications revealed that carboxyemimycin affected the development of E. tenella in first and second generation schizogony and in gametogony. 相似文献
958.
A New Phaeodarian Species Discovered from the Japan Sea Proper Water,Auloscena pleuroclada sp. nov. (Aulosphaeridae,Phaeosphaerida, Phaeodaria)
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![点击此处可从《The Journal of eukaryotic microbiology》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Yasuhide Nakamura Ichiro Imai Akihiro Tuji Noritoshi Suzuki 《The Journal of eukaryotic microbiology》2016,63(2):271-274
A new phaeodarian species, characterized by the presence of long developed side branches recurved proximally and distally on the surface of its radial tube, was described as Auloscena pleuroclada. This new species was only collected from the layers below the 250 m depth in the Sea of Japan. They have never been found in the shallower layers (above 250 m) of this sea or in other investigated areas. The distribution of the present new species is presumably restricted within the deep water of this area, and this species could be a specific phaeodarian adapted to the deep‐sea environment. 相似文献
959.
960.
Hirohisa Okabe Hiroki Kinoshita Katsunori Imai Shigeki Nakagawa Takaaki Higashi Kota Arima Hideaki Uchiyama Toru Ikegami Norifumi Harimoto Shinji Itoh Takatoshi Ishiko Tomoharu Yoshizumi Toru Beppu Satdarshan P. S. Monga Hideo Baba Yoshihiko Maehara 《PloS one》2016,11(4)
Aimβ-catenin signaling is a major oncogenic pathway in hepatocellular carcinoma (HCC). Since β-catenin phosphorylation by glycogen synthase kinase 3β (GSK3β) and casein kinase 1ε (CK1ε) results in its degradation, mutations affecting these phosphorylation sites cause β-catenin stabilization. However, the relevance of missense mutations in non-phosphorylation sites in exon 3 remains unclear. The current study explores significance of such mutations in addition to addressing the clinical and biological implications of β-catenin activation in human HCC.MethodsGene alteration in exon3 of CTNNB1, gene expression of β-catenin targets such as glutamate synthetase (GS), axin2, lect2 and regucalcin (RGN), and protein expression of β-catenin were examined in 125 human HCC tissues.ResultsSixteen patients (12.8%) showed conventional missense mutations affecting codons 33, 37, 41, and 45. Fifteen additional patients (12.0%) had other missense mutations in codon 32, 34, and 35. Induction of exon3 mutation caused described β-catenin target gene upregulation in HCC cell line. Interestingly, conventional and non-phosphorylation site mutations were equally associated with upregulation of β-catenin target genes. Nuclear localization of β-catenin was associated with poor overall survival (p = 0.0461). Of these patients with nuclear β-catenin localization, loss of described β-catenin target gene upregulation showed significant poorer overall survival than others (p = 0.0001).ConclusionThis study suggests that both conventional and other missense mutations in exon 3 of CTNNB1 lead to β-catenin activation in human HCC. Additionally, the mechanism of nuclear β-catenin localization without upregulation of described β-catenin target genes might be of clinical importance depending on distinct mechanism. 相似文献