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1.
Deoxyribonucleic acid hybridization among strains of lactobacilli   总被引:1,自引:0,他引:1  
Hybridization of deoxyribonucleic acid (DNA) from Lactobacillus bulgaricus (ATCC 11842) with DNA of L. lactis (ATCC 12315), L. helveticus (ATCC 15009), and L. jugurt (ATCC 521) showed 86.0% reassociation with L. lactis, 4.8% with L. helveticus, and none with L. jugurt.  相似文献   
2.
3.
Preparation, properties and metabolism of 5,6-monoepoxyretinoic acid   总被引:4,自引:3,他引:1  
1. Methyl retinoate has been converted into methyl 5,6-monoepoxyretinoate by reaction with monoperphthalic acid. The epoxy acid ester on alkaline hydrolysis gave 5,6-monoepoxyretinoic acid. 2. Treatment of the 5,6-monoepoxy compounds with ethanolic hydrochloric acid gave the corresponding 5,8-epoxy (furanoid) compounds. 3. With lithium aluminium hydride, the acid and the ester groups were selectively reduced to primary alcohols. 4. Administration of methyl 5,6-monoepoxyretinoate intraperitoneally and subcutaneously had good growth response in vitamin A-deficient rats. 5. 5,6-Monoepoxyretinoic acid, when given intraperitoneally as the sodium salt, was 157% as active as all-trans-retinyl acetate. 6. Methyl 5,6-monoepoxyretinoate was hydrolysed to the epoxy acid by rat-liver homogenate. It had 35% of the biological activity of all-trans-retinyl acetate in the rat when given orally.  相似文献   
4.
Summary The renal localization and the site of synthesis of epidermal growth factor (EGF) were investigated in the rat kidney by immunohistochemistry and in situ hybridization techniques. EGF was localized in the cells of the thick ascending limb of Henle (TAL) and distal convoluted tubule (DCT). At the ultrastructural level, EGF immunoreactivity was distributed on the apical membrane and trans-Golgi complex of the TAL and DCT cells. These segments of the rat nephron also hybridized to prepro-EGF cRNA probes in a specific manner, indicating that TAL and DCT are the sites of EGF synthesis in the rat kidney.  相似文献   
5.
The plasma membrane enzymes, alkaline phosphatase, bicarbonate-dependent adenosine triphosphatase, 5'-nucleotidase, and carbonate dehydratase, were measured in ductal and acinar preparations of bovine pancreas. Epithelial cells were scraped from the main duct and a piece of acinar tissue was dissected from the whole pancreas for homogenization. All enzymes studied demonstrated higher levels in the duct per milligram protein than in the acinus: bicarbonate-dependent adenosine triphosphatase was 2.8 times higher; 5'-nucleotidase, 4.1 times higher; carbonate dehydratase, 16.9 times higher, while alkaline phosphatase showed only a slight increase in the duct compared to acini.  相似文献   
6.
Very low density lipoproteins, chylomicrons, and remnants caused, within an hour, significant inhibition of fatty acid synthesis but not cholesterol synthesis in hepatocytes isolated from meal-fed rats. In contrast, low density lipoproteins, high density lipoproteins, and the serum fraction of density greater than 1.21 failed to significantly inhibit either fatty acid or cholesterol synthesis within 1 h. The Scatchard plots of specific binding showed that rat and human very low density lipoproteins interact with the high affinity sites on the hepatocytes with the apparent dissociation constants of 64 and 106 nM, respectively. These data also indicated that each hepatocyte was capable of binding 6 X 10(5) molecules of very low density lipoproteins.  相似文献   
7.
The therapeutic effects of lithium in bipolar disorder are poorly understood. Lithium decreases free inositol levels by inhibiting inositol monophosphatase 1 and myo-inositol 3-phosphate synthase (IPS). In this study, we demonstrate for the first time that IPS can be phosphorylated. This was evident when purified rat IPS was dephosphorylated by lambda protein phosphatase and analyzed by phospho-specific ProQ-Diamond staining and Western blot analysis. These techniques demonstrated a mobility shift consistent with IPS being phosphorylated. Mass spectral analysis revealed that Serine-524 (S524), which resides in the hinge region derived from exon 11 of the gene, is the site for phosphorylation. Further, an antibody generated against a synthetic peptide of IPS containing monophosphorylated-S524, was able to discriminate the phosphorylated and non-phosphorylated forms of IPS. The phosphoprotein is found in the brain and testis, but not in the intestine. The intestinal IPS isoform lacks the peptide bearing S524, and hence, cannot be phosphorylated. Evidences suggest that IPS is monophosphorylated at S524 and that the removal of this phosphate does not alter its enzymatic activity. These observations suggest a novel function for IPS in brain and other tissues. Future studies should resolve the functional role of phospho-IPS in brain inositol signaling.  相似文献   
8.
The uptake, by oysters, of glucose is approximately 10–15 ng/hr/g wet weight, when glucose concentration in the saline was at 50 μg/ml. The removal of inorganic orthophosphate was approximately at a rate of 0.36 ng/hr/g wet weight. Radioactive studies indicate that these substrates are metabolized by oysters. The technique developed can be used to study oyster metabolism in the laboratory.  相似文献   
9.
International Journal of Peptide Research and Therapeutics - Biofilm forming pathogens are among the major causes of hospital-acquired infections and are not much affected by antibiotic treatment....  相似文献   
10.
Abstract

In this work, we have synthesized a few novel mononuclear complexes of Cu(II), Co(II), Ni(II) and Zn(II) using a pyrazolone-derived Schiff base ligand. They were characterized by spectroscopic and analytical methods. The elemental analyses, UV-Vis, magnetic moment values and molar conductance of the complexes reveal that the complexes adopt an octahedral arrangement around the central metal ions. The interaction of complexes with CT-DNA was studied by absorption spectral titration and viscosity measurements. The observed data show that the complexes bind with CT-DNA via an intercalation mode. Efficient pUC18 DNA cleavage ability of the synthesized compounds was explored by gel electrophoresis. The antimicrobial activity of these compounds against a set of bacterial and fungal strains reveals that the complexes exhibit better activity than the free ligand. Moreover, all the complexes were evaluated against two cancer (HeLa and HepG2) and one normal (NHDF) cell lines. The data were compared with cisplatin. Anti–inflammatory activity has been experimentally validated which proves that theoretical predictions concur with the experimental results. In addition, molecular docking studies have been performed to consider the nature of binding mode and binding affinity of these compounds with DNA (1BNA) and protein (3hb5). These studies reveal that the mode of binding is intercalation and the complexes have higher binding energy scores than the free ligand.  相似文献   
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