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Small amounts of metabolite-binding protein (MBP) originally characterized from the bile were detected in rat serum and cytosol by an indirect enzyme-linked immunoabsorbant assay. The site of MBP synthesis was shown to be the liver based upon results of (1) the in vitro translation of liver poly(A)+ mRNA, followed by immunoprecipitation with anti-MBP sera and sodium dodecyl sulfate-polyacrylamide gel electrophoresis and fluorography of the immunoprecipitate, and (2) immunoprecipitation of bile collected from [3H]leucine perfused liver in situ and SDS-polyacrylamide gel electrophoresis and fluorography of the immunoprecipitate. To determine whether part of the MBP in bile is derived from the circulation, [125I]MBP was injected intravenously and bile was collected and subjected to SDS-polyacrylamide gel electrophoresis and fluorography. Intact [125]MBP was not detected in bile even though several other iodinated bile proteins were taken up by the liver from the circulation and secreted intact into the bile under similar experimental conditions. These data indicate that MBP is synthesized in the liver and secreted into the bile and circulation independently. In addition, MBP was not found in brain, spleen or kidneys.  相似文献   
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Following administration of phenobarbital to rats, liver ligandin content, bilirubin binding, glutathione-S-transferase and steriod isomerase activities by 150% and the 22 000-dalton subunit was selectively increased. Following adminstration of 3′-methyl-N,N-dimethyl-4-aminoazobenzene, rat liver ligandin content and steroid isomerase decrased by 65%, glutathione-S-transferase incrased by 100%, bilirubin binding was abolished, and the relative proportion of the 22 000- and 25 000-dalton subunits remained unchanged.  相似文献   
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A method of microcloning via somatic embryogenesis was established in date palm (Phoenix dactylifera L) cultivars. The method has potential for commercial application. Embryogenic cultures were initiated from soft primordial tissues of 2-3-year-old female suckers. The system was optimized first for the genotype ’sayar’ and then its applicability was tested to other genotypes. A method of pre-acclimation using pre-acclimation chambers has been devised, which improved hardening survival greatly. More than 80 clones obtained from the genotype ’sayar’ have been shifted to field for agronomic evaluation.  相似文献   
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Abstract

From 24 hour collections of urines of chronic myelogenous leukemia (CML) patients, a novel nucleoside was isolated. It was assigned the structure, 5′-deoxyinosine (I) on the basis of UV, NMR and mass spectrometry and by comparison of the spectral data and HPLC and TLC mobilities with those of the authentic sample. Another nucleoside, 5′-deoxy-5′-methylthioadenosine sulfoxide previously isolated from the urines of immunodeficient children was also found in the urine of a CML patient. Possible origin and significance of both of these nucleosides are discussed.  相似文献   
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Bhargava, H. N., V. M. Villar, J. Cortijo and E. J. Morcillo. Binding of [3H][D-Ala2, MePhe4, Gly-ol5]enkephalin, [3H][D-Pen2, D-Pen5]enkephalin, and [3H]U-69,593 to airway and pulmonary tissues of normal and sensitized rats. Peptides 18(10) 1603–1608, 1997.—The role of endogenous opioid peptides in the regulation of bronchomotor tone, as well as in the pathophysiology of asthma is uncertain. We have studied the binding of highly selective [3H]labeled ligands of μ-([D-Ala2, MePhe4, Gly-ol5]enkephalin; DAMGO), δ ([D-Pen2, D-Pen5]enkephalin; DPDPE), and κ-(U-69,593) opioid receptors to membranes of trachea, main bronchus, lung parenchyma and pulmonary artery obtained from normal (unsensitized) and actively IgE-sensitized rats acutely challenged with the specific antigen. [3H]DAMGO, [3H]DPDPE and [3H]U-69,593 bound to membranes of normal and sensitized tissues at a saturable, single high-affinity site. The rank order of receptor densities in normal tissues was δ- ≥ κ- ≥ μ-, with lung parenchyma exhibiting the greatest binding capacity for δ- and μ- receptors compared to the other regions examined. The Kd values showed small differences between ligands and regions tested. The μ- and δ-opioid receptor densities were decreased in sensitized main bronchus and lung parenchyma, respectively, compared to normal tissues. By contrast, κ-opioid receptor density was augmented in sensitized lung parenchyma but an increase in Kd values was also observed. These differential changes in the density and affinity of opioid receptor types may be related to alterations in endogenous opioid peptides during the process of sensitization.  相似文献   
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