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C Richard A Demarly K K Han M Dautrevaux 《The International journal of biochemistry》1984,16(7):727-732
During structural analysis of Lobster muscle arginine-kinase, we have isolated a CNBr resulting peptide with a blocked N-terminal residue. This peptide was sequenced after unblocking by mild acid treatment (1 N HCl at 100 degrees C for 10 min). The blocked form is not due to the formation of pyroglutamic acid nor is it due to the formation of diketopiperazine. We have applied the experimental conditions used for CNBr cleavage of lobster arginine-kinase to a synthetic peptide the structure of which is similar to the above CNBr peptide. We bring evidence that during CNBr cleavage partial formylation occurs with a possible cyclization of a 7 membered ring of Gly--Asp... 相似文献
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The Raman spectroscopic lines of liquid cultures of Rhizobium japonicum have been compared with electron microscopic examinations and growth measurements of these cells. The results showed that the significant Raman lines are related to the reproduction activities of the procaryotic cells. 相似文献
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C K Hill A Han M M Elkind 《International journal of radiation biology and related studies in physics, chemistry, and medicine》1984,46(1):11-15
The neoplastic transformation of C3H 10T1/2 cells induced by fission-spectrum neutrons delivered at a high dose rate is linear up to 40 cGy. Reducing the dose rate increases the frequency of transformation in the low dose region. At a dose rate of 0.086 cGy min-1, the initial part of the induction curve remains linear but it has a slope 9-fold greater than the initial part of the curve at a high dose rate. 相似文献
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Rong‐rong Zhu Qian Chen Zhi‐bo Liu Han‐guang Ruan Qi‐cai Wu Xue‐liang Zhou 《Journal of cellular and molecular medicine》2020,24(14):7907-7914
Increased expression and activity of cardiac and circulating cathepsin D and soluble fms‐like tyrosine kinase‐1 (sFlt‐1) have been demonstrated to induce and promote peripartum cardiomyopathy (PPCM) via promoting cleavage of 23‐kD prolactin (PRL) to 16‐kD PRL and neutralizing vascular endothelial growth factor (VEGF), respectively. We hypothesized that activation of Hes1 is proposed to suppress cathepsin D via activating Stat3, leading to alleviated development of PPCM. In the present study, we aimed to investigate the role of Notch1/Hes1 pathway in PPCM. Pregnant mice between prenatal 3 days and postpartum 3 weeks were fed with LY‐411575 (a notch inhibitor, 10 mg/kg/d). Ventricular function and pathology were evaluated by echocardiography and histological analysis. Western blotting analysis was used to examine the expression at the protein level. The results found that inhibition of Notch1 significantly promoted postpartum ventricular dilatation, myocardial hypertrophy and myocardial interstitial fibrosis and suppressed myocardial angiogenesis. Western blotting analysis showed that inhibition of Notch1 markedly increased cathepsin D and sFlt‐1, reduced Hes1, phosphorylated Stat3 (p‐Stat3), VEGFA and PDGFB, and promoted cleavage of 23k‐D PRL to 16‐kD PRL. Collectively, inhibition of Notch1/Hes1 pathway induced and promoted PPCM via increasing the expressions of cathepsin D and sFlt‐1. Notch1/Hes1 was a promising target for prevention and therapeutic regimen of PPCM. 相似文献
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