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排序方式: 共有1499条查询结果,搜索用时 31 毫秒
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The NH2-terminal residues of Bacillus subtilis proteins 总被引:4,自引:0,他引:4
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N Tomita A Horii S Doi H Yokouchi K Shiosaki M Higashiyama N Matsuura M Ogawa T Mori K Matsubara 《Gene》1989,76(1):11-18
A novel type of alpha-amylase was detected in a lung carcinoid tissue after surveying the cDNA library constructed from this tumor mRNA. Nucleotide sequence analysis showed that the amylase expressed in this carcinoid tumor has 13 and 6 amino acid substitutions when compared with salivary amylase (Amy1) and pancreatic amylase (Amy2), respectively. The nucleotide sequence homologies of cDNAs between this carcinoid amylase and amy1, amy2 are 97.5% and 98.2%, respectively. The nucleotide sequence comparison strongly suggests that this new amylase is the product of the amy3 gene that has been detected in human genome [Emi et al., Gene 62 (1988) 229-235] 相似文献
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S Sumi K Inoue R Hosotani M Kogire R Doi M Yun S Higashide H Minote K Takaori H Kaji 《Life sciences》1990,47(13):1115-1119
The effect of intravenous administration of human epidermal growth factor on the splanchnic blood flows was examined in anesthetized dogs, using an ultrasonic transit-time volume flow meter. Human epidermal growth factor (0.1, 0.5 and 1 microgram/kg) significantly increased blood flows in the portal vein (36.9 +/- 7.4% at 1 microgram/kg) and the superior mesenteric artery (49.0 +/- 16.8% at 1 microgram/kg). Systemic blood pressure monitored simultaneously was significantly decreased (8.4 +/- 1.2% at 1 microgram/kg). This study is the first to demonstrate that intravenous administration of epidermal growth factor increases the portal venous blood flow. 相似文献
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Shinichiro Nakamura Wijit Kiatipattanasakul Hiroyuki Nakayama Fumiko Ono Ippei Sakakibara Yasuhiro Yoshikawa Naoaki Goto Kunio Doi 《Journal of medical primatology》1996,25(4):294-300
Abstract: In this study, we immunohistochemically examined the several constituents of senile plaques (SPs) and cerebral amyloid angiopathy (CAA) in aged cynomolgus monkeys. Apolipoprotein E (apoE) deposited in all mature plaques and CAA, and in half of the diffuse plaques. Alpha-1-antichymotripsin (αACT) deposited in half of the mature plaques and in one third of the CAA. Amyloid precursor protein (APP), ubiquitin (Ub), and microtubule-associated protein-2 (MAP-2) accumulated in the swollen neurites of mature plaques. Glial fibrillary acidic protein (GFAP) was detected in the astrocytes and their processes surrounding the mature plaques. Tau was detected in neither the SPs nor CAA. Therefore, mature plaques involved extracellular Aβ, apoE, and αACT, and also astrocytes and swollen neurites. However, diffuse plaques involved only extracellular Aβ and apoE. Since these features, except for tau, were consistent with those in humans, this animal model will be useful for studying the pathogenesis of cerebral amyloid deposition. 相似文献
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Streptomyces azureus ATCC 14921 harboured a plasmid pSA1 together with its chromosomal integrated sequence (pSA1int ). The att P site on the plasmid was located at ca 170 bp Bam HI- Sph I fragment by site-specific integration. The free form was generated from the integrated sequence during the development of its host mycelia in the solid culture, but not in the liquid culture. The free form seemed to elicit the formation of spontaneously developing pocks on its host mycelia in the solid culture. 相似文献
20.
Mutation analysis of the cellulose-binding domain of the Clostridium cellulovorans cellulose-binding protein A. 总被引:1,自引:0,他引:1 下载免费PDF全文
Cellulose-binding protein A (CbpA) has been previously shown to mediate the interaction between crystalline cellulose substrates and the cellulase enzyme complex of Clostridium cellulovorans. CbpA contains a family III cellulose-binding domain (CBD) which, when expressed independently, binds specifically to crystalline cellulose. A series of N- and C-terminal deletions and a series of small internal deletions of the CBD were created to determine whether the entire region previously described as a CBD is required for the cellulose-binding function. The N- and C-terminal deletions reduced binding affinity by 10- to 100-fold. Small internal deletions of the CBD resulted in substantial reduction of CBD function. Some, but not all, point mutations throughout the sequence had significant disruptive effects on the binding ability of the CBD. Thus, mutations in any region of the CBD had effects on the binding of the fragment to cellulose. The results indicate that the entire 163-amino-acid region of the CBD is required for maximal binding to crystalline cellulose. 相似文献