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1.
The effects of humic substances on in vitro culture of Golden Delicious apple are reported. Potassium humate (KH) when used in proliferation showed a negative interaction with BA while it enhanced rooting when IBA was not present in the culture medium. In the presence of IBA, KH increased root number and reduced root growth. The highest concentration tested, 500 mg l-1, caused a drastic reduction in root system development. 50 mg l-1 KH hastened rooting and plants grew more rapidly when transferred to soil.  相似文献   
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3H-Naloxone was used to demonstrate the presence of specific opiate binding sites in uterine membrane preparations of rats. 3H-Naloxone binding (0.41-27 nM) was found to be rapid, saturable and reversible showing two populations of binding sites with the characteristic of high (KD 2.2 nM; Bmax 46.6 fmol/mg prot.) and low (KD 18.1 nM; Bmax 143.7 fmol/mg prot.) affinity. The number and affinity of the binding sites labelled by 3H-naloxone in the uterus were measured in the rat at mid (14 days), late (21 days) pregnancy and at parturition. The high and low affinity recognition sites labelled by 3H-naloxone showed a consistent reduction during pregnancy and at parturition without changes in the affinity constant. We concluded that pregnancy and parturition are associated with significant changes in the number of the opiate receptors bound in the uterus by 3H-naloxone. This phenomenon which seems to be linked with the several pregnancy-related changes in the levels of endogenous peptides and hormones could be relevant to further explain the pregnancy related changes in pain perception and maternal behavior.  相似文献   
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The morphogenic effect of different light wavelengths on in vitro rooting of Prunus insititia GF655-2 in relation to the presence of napthaleneacetic acid (NAA) in the culture medium was investigated. Results of experiments in which plantlets were rooted in NAA enriched medium showed that the presence of auxin induced rooting even in the dark after an initial lag period. Illumination of the cultures with Red light was as effective in promoting rooting as treatment with 0.5 M NAA; Red was more active in stimulating rooting in the short term than was NAA. The pattern of root formation resulting from the addition of NAA appeared to dominate development under White, Blue and Far Red treatments. Although it was possible to correlate the rooting response to the phytochrome photoequilibrium induced by the light treatments used, there arises a possible interference of specific Blue absorbing photoreceptors.Abbreviations B Blue - FR Far Red - HIR High Irradiance Response - Pfr active (far-red absorbing) form of phytochrome - Ptot total phytochrome - R Red - W White - NAA -naphtaleneacetic acid - BA benzyladenine - IAA indole 3-acetic acid  相似文献   
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Summary Dehydrocholic acid (3,7,12-trioxo-5-cholanic acid) (0.5% concentration) was completely and selectively reduced to 12-ketoursodeoxycholic acid (3, 7-dihydroxy-12-oxo- 5-cholanic acid) in a membrane reactor by means of 3-hydroxysteroid dehydrogenase and 7-hydroxysteroid dehydrogenase. Coenzyme regeneration was carried out with the glucose-glucose dehydrogenase system.  相似文献   
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Molecular Biology Reports - Serine hydrolases play crucial roles in many physiological and pathophysiological processes and a panel of these enzymes are targets of approved drugs. Despite this,...  相似文献   
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Di Francesco  A.  Di Foggia  M.  Corbetta  M.  Baldo  D.  Ratti  C.  Baraldi  E. 《Journal of Plant Growth Regulation》2021,40(3):1233-1244

The most common leguminous plants’ diseases are caused by soil-borne pathogens leading to important economic losses worldwide. Strains L1 and L8, belonging to Aureobasidium pullulans species, were tested in vitro and in vivo as biocontrol agents (BCAs) against Rhizoctonia solani (Rs1) (AG-4) and as plant growth promoters (PGPs). The non-volatile metabolites produced by L1 and L8 strains inhibited the pathogen mycelial growth by 87.9% on average, with no significant differences between the two strains. The lower pathogen diametric growth inhibition was displayed by both yeasts’ volatile metabolites (VOCs) that significantly reduced the colony growth of R. solani, and similarly to the control, with an average of 10.5%. By in vivo assay, L1 and L8 strains showed the ability to control the pathogen virulence probably through the biofilm formation around the bean and soybean plant roots, as confirmed by scanning electron microscope (SEM) analysis. The spectroscopic analysis highlighted the composition of non-volatile compounds: complex carbohydrates (pullulan), degrading enzymes, siderophores and antifungals (aureobasidins). Moreover, the ability of L1 and L8 strains to stimulate the bean and soybean plant roots, stems, and leaves growth was investigated, showing that these yeasts could have an application not only as BCAs but also as plant growth biostimulator.

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10.
The effect of omeprazole on the mitochondrial carnitine/acylcarnitine transporter has been studied in proteoliposomes. Externally added omeprazole inhibited the carnitine/carnitine antiport catalysed by the transporter. The inhibition was partially reversed by DTE indicating that it was caused by the covalent reaction of omeprazole with Cys residue(s). Inhibition of the C-less mutant transporter indicated also the occurrence of an alternative non-covalent mechanism. The IC50 of the inhibition of the WT and the C-less CACT by omeprazole were 5.4 µM and 29 µM, respectively. Inhibition kinetics showed non competitive inhibition of the WT and competitive inhibition of the C-less. The presence of carnitine or acylcarnitines during the incubation of the proteoliposomes with omeprazole increased the inhibition. Using site-directed Cys mutants it was demonstrated that C283 and C136 were essential for covalent inhibition. Molecular docking of omeprazole with CACT indicated the formation of both covalent interactions with C136 and C283 and non-covalent interactions in agreement with the experimental data.  相似文献   
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