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71.
Marked increases of two kinds of two-exon-skipped albumin mRNAs with aging and their further increase by treatment with 3''-methyl-4-dimethylaminoazobenzene in Nagase analbuminemic rats. 总被引:2,自引:1,他引:2 下载免费PDF全文
T Kaneko H Shima H Esumi M Ochiai S Nagase T Sugimura M Nagao 《Proceedings of the National Academy of Sciences of the United States of America》1991,88(7):2707-2711
Nagase analbuminemic rats (NARs) have a 7-base-pair deletion at the 5' splice site of the HI intron of the albumin gene. The level of immunohistochemically albumin-positive hepatocytes is about 1 per 10(5) cells in neonatal NARs, increases with age, and further increases with chronic oral treatment with 3'-methyl-4-dimethylaminoazobenzene (3'-MeDAB). The mechanisms involved in the increase in albumin-positive hepatocytes during aging of NARs and their treatment with 3'-MeDAB were analyzed. NARs were found to have four species of albumin mRNA: intact mRNA and those lacking the regions corresponding to exon H, exon G-H, and exon H-I. In 4-week-old NARs, the level of intact albumin mRNA was about 1/4000 of that in normal rats and mRNA lacking the exon H sequence was the major species. In aged and 3'-MeDAB-treated aged NARs, all four species of mRNA increased and the relative proportion of mRNAs lacking two exon sequences to mRNAs lacking one exon sequence was greatly increased, suggesting that aging is associated with changes of the splicing pattern and that 3'-MeDAB treatment enhanced these changes. In aged NARs and 3'-MeDAB-treated aged NARs, there was an increase in the amount of aberrant 60-kDa albumin. The 60-kDa protein could be a translation product of mRNAs lacking two exons, the amount of which increases in aged NARs and 3'-MeDAB-treated NARs. 相似文献
72.
The Impact of the Macroeconomy on Health Insurance Coverage: Evidence from the Great Recession 下载免费PDF全文
This paper investigates the impact of the macroeconomy on the health insurance coverage of Americans using panel data from the Survey of Income and Program Participation for 2004–2010, a period that includes the Great Recession of 2007–2009. We find that a one percentage point increase in the state unemployment rate is associated with a 1.67 percentage point (2.12%) reduction in the probability that men have health insurance; this effect is strongest among college‐educated, white, and older (50–64 years old) men. For women and children, health insurance coverage is not significantly correlated with the unemployment rate, which may be the result of public health insurance acting as a social safety net. Compared with the previous recession, the health insurance coverage of men is more sensitive to the unemployment rate, which may be due to the nature of the Great Recession. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
73.
Yorinari Ochiai Akira Matsui Shinji Ito Yutaka Takazawa Daisuke Kikuchi Shu Hoteya 《Internal medicine (Tokyo, Japan)》2021,60(4):533
A 45-year-old man visited our institution due to the onset of hematochezia. He had a previous episode nine years earlier and colonoscopy at that time revealed multiple polyps, which were consistent with inflammatory cloacogenic polyps (ICPs) on the dentate line. Colonoscopy was performed again and two of the ICPs had grown. Both lesions were pathologically diagnosed as adenocarcinomas based on biopsies. Endoscopic submucosal dissection (ESD) was performed and the two lesions were diagnosed as double well-differentiated adenocarcinomas arising from ICPs. To our knowledge, this is the first reported case of double early rectal cancer in ICPs, which were followed endoscopically and successfully resected with ESD. 相似文献
74.
Takahiko Funabiki Yoichi Sakurai Masahiro Ochiai Yoshihisa Marugami Toshiki Matsubara Shigeru Hasegawa 《Journal of hepato-biliary-pancreatic sciences》1997,4(1):71-77
End-to-side choledochoduodenostomy was originally used for reconstruction between the duodenum and the biliary tree in iatrogenic bile duct stricture. However, we believe the procedure could be applied for various biliary disorders. We have recently shown the high carcinogenicity of biliary epithelium in patients with pancreaticobiliary maljunction, and consequently we recommend excision of the bile duct, along with appropriate reconstruction of the biliary system to divert the flow of pancreatic juice from bile fluid, to prevent carcinoma in biliary epithelium even in patients without dilatation of the bile duct. The conditions causing primary or recurrent bile duct stones must be removed. We employed this procedure for biliary reconstruction in 42 patients with pancreatico-biliary maljunction and in 30 patients with various benign biliary diseases, such as bile duct stones and benign biliary stenosis. We also used the procedure for palliation in 6 patients with malignant tumors around the head of the pancreas. Among these 78 patients over 20 years, we experienced 5 cases of reflux cholangitis with anastomotic stenosis, for which conservative dilatation was required. This procedure of end-to-side choledochoduodenostomy could be widely applicable for biliary reconstruction in terms of its being simplicity, minimal invasiveness and the establishment of a single physiological route for bile flow into the duodenum. 相似文献
75.
Azuma Minako Nakada Hiroshi Takei Mizuki Nakamura Keigo Katsuragawa Shigehiko Shinkawa Norihiro Terada Tamasa Masuda Rie Hattori Youhei Ide Takakazu Kimura Aya Shimomura Mei Kawano Masatsugu Matsumura Kengo Meiri Takayuki Ochiai Hidenobu Hirai Toshinori 《Emergency radiology》2022,29(2):425-425
Emergency Radiology - 相似文献
76.
Suzuki A Nagasako K Fujimori T Ono Y Suzuki S Hayashi N 《Journal of gastroenterology》2000,35(11):832-839
We examined differences in the degree of differentiation in intramucosal and submucosal areas of involvement in early colorectal
adenocarcinomas of 131 patients and compared these findings with tumor morphology. In addition, K-ras and p53 protein expression was determined in cases where poorly differentiated adenocarcinoma was detected in the submucosa.
We identified 6 patients with both intramucosal differentiated (well-to-moderately differentiated) adenocarcinoma and submucosal
poorly differentiated adenocarcinoma (MwSp). The morphological tumor type was superficial in all MwSp cases. The observed
MwSp adenocarcinomas had a significantly higher frequency of lymphatic invasion than the more common superficial type of adenocarcinoma.
Genetic analysis of these MwSp lesions was carried out using the polymerase chain reaction-restriction fragment-length polymorphism
(PCR-RFLP) method to detect the presence of K-ras codon 12 point mutations, and an immunologic staining technique was used to identify the presence of p53 protein overexpression.
The K-ras mutation rate was 33.3%, and the p53 overexpression rate was 66.7% for the MwSp adenocarcinomas. Our findings suggest that the rapidly reduced histologic differentiation
observed in some of these superficial colorectal adenocarcinomas may play a role in their higher degree of invasiveness.
Received: November 17, 1999 / Accepted: July 7, 2000 相似文献
77.
Molecular cloning of insect pro-phenol oxidase: a copper-containing protein homologous to arthropod hemocyanin. 总被引:6,自引:3,他引:6 下载免费PDF全文
T Kawabata Y Yasuhara M Ochiai S Matsuura M Ashida 《Proceedings of the National Academy of Sciences of the United States of America》1995,92(17):7774-7778
Pro-phenol oxidase [pro-PO; zymogen of phenol oxidase (monophenol, L-dopa:oxygen oxidoreductase, EC 1.14.18.1)] is present in the hemolymph plasma of the silkworm Bombyx mori. Pro-PO is a heterodimeric protein synthesized by hemocytes. A specific serine proteinase activates both subunits through a limited proteolysis. The amino acid sequences of both subunits were deduced from their respective cDNAs; amino acid sequence homology between the subunits was 51%. The deduced amino acid sequences revealed domains highly homologous to the copper-binding site sequences (copper-binding sites A and B) of arthropod hemocyanins. The overall sequence homology between silkworm pro-PO and arthropod hemocyanins ranged from 29 to 39%. Phenol oxidases from prokaryotes, fungi, and vertebrates have sequences homologous to only the copper-binding site B of arthropod hemocyanins. Thus, silkworm pro-PO DNA described here appears distinctive and more closely related to arthropod hemocyanins. The pro-PO-activating serine proteinase was shown to hydrolyze peptide bonds at the carboxyl side of arginine in the sequence-Asn-49-Arg-50-Phe-51-Gly-52- of both subunits. Amino groups of N termini of both subunits were indicated to be N-acetylated. The cDNAs of both pro-PO subunits lacked signal peptide sequences. This result supports our contention that mature pro-PO accumulates in the cytoplasm of hemocytes and is released by cell rupture, as for arthropod hemocyanins. 相似文献
78.
Masatoshi Murata Asako Ooe Tomonori Izumi Michihiro Nakagawa Shigeki Takahashi Masaaki Ishikawa Kazuo Mori & Akitada Ichinose 《British journal of haematology》1997,99(2):301-303
Dysplasminogenaemia has been reported in patients with retinochoroidal vascular disorders. The precise genetic defects of these cases, however, remain unclear because of the limitations of conventional diagnostic techniques. In this study, three patients with these diseases were investigated at the DNA level for the first time to define the molecular bases of these disorders. Polymerase chain reaction–restriction fragment length polymorphism analysis revealed that all three cases carried the same Ala601-Thr mutation. This defect may also play a role in the pathogenesis of circulation disorders in small local vessels because of reduced fibrinolytic activity due to decreased functional plasminogen levels. 相似文献
79.
80.
Kohzoh Hisanaga Asako Hisanaga Kazuhiko Nagata Yoshiyasu Ichie 《American heart journal》1980,100(5):605-609
A transesophageal cardiac imaging system is described. This system employs hand-held mechanical sector and linear scanners each having a flexible tube and a small ultrasonic transducer contained within a small oil bag easily swallowed by adults. In the sector scanner, a small transducer in the esophagus rotates alternately and horizontal heart images are displayed. In the linear scanner, a small transducer in the esophagus moves up and down and vertical heart images are displayed. The system was evaluated in 31 adult subjects. In all subjects, stable high quality heart images were observed continuously from base to apex as the transducer was being withdrawn or advanced in the esophagus. In horizontal scans, entire heart images were observed at the level of the atrioventricular valves. In vertical scans, the bifurcation of the pulmonary artery could be observed clearly. There was little difference in the image quality among subjects. 相似文献