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The isolated molecular forms of guinea-pig skeletal muscle cytoplasmic malate dehydrogenase have a different chromatographic behaviour through affinity or hydrophobic interaction gels; in all cases the retention of the B form is more noticeable. Chromatography of a partly purified preparation through 5' AMP-Sepharose allows both molecular forms of malate dehydrogenase to be separated and obtained free from lactate dehydrogenase.  相似文献   
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Puig  S.  Querol  A.  Ramón  D.  Pérez-Ortín  J. E. 《Biotechnology letters》1996,18(8):887-892
Summary Genes as POT1, HSP104 and SSA3, which are late expressed in laboratory culture conditions are expressed only during the first few days in microvinifications in wine yeast cells. This effect is probably due to the different growth conditions and leads to useless levels of enzyme activity for a reporter gene. However the ACT1 promoter, which is constitutively expressed in laboratory conditions, produces sufficient amounts of enzyme activity in late fermentation phases.  相似文献   
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Abstract: The effect of lindane administration on the specific binding of ligands to different sites on the GABAA receptor-ionophore complex was studied in the rat brain by receptor mapping autoradiography. [3H]Muscimol (Mus), [3H]flunitrazepam (Flu), and t -[35S]butylbicyclophosphorothionate (TBPS) were used as specific ligands of GABA, benzodiazepine, and picrotoxinin binding sites, respectively. Rats received a single oral dose of 30 mg/kg lindane and they were classified into two groups according to the absence or presence of convulsions. Vehicle-treated groups acted as controls. The effect of the xenobiotic on ligand binding was measured in different brain areas and nuclei 12 min or 5 h after its administration. Lindane induced a generalized decrease in [35S]TBPS binding, which was present shortly after dosing. In addition, [3H]Flu binding was increased in lindane-treated animals, this modification also appearing shortly after administration but diminishing during the studied time. Finally, lindane induced a decrease in [3H]Mus binding, which became more evident over time. These modifications were observed both in the presence and in the absence of convulsions. However, an increase in [3H]-Mus binding was detected shortly after lindane-induced convulsions. The observed decrease in [35S]TBPS binding is in agreement with the postulated action of lindane at the picrotoxinin binding site of the GABAA receptor chloride channel. The effects observed on the binding of [3H]Flu and [3H]Mus may be secondary to the action of lindane as an allosteric antagonist of the GABAA receptor.  相似文献   
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Microfluidic technologies are highly adept at generating controllable compositional gradients in fluids, a feature that has accelerated the understanding of the importance of chemical gradients in biological processes. That said, the development of versatile methods to generate controllable compositional gradients in the solid‐state has been far more elusive. The ability to produce such gradients would provide access to extensive compositional libraries, thus enabling the high‐throughput exploration of the parametric landscape of functional solids and devices in a resource‐, time‐, and cost‐efficient manner. Herein, the synergic integration of microfluidic technologies is reported with blade coating to enable the controlled formation of compositional lateral gradients in solution. Subsequently, the transformation of liquid‐based compositional gradients into solid‐state thin films using this method is demonstrated. To demonstrate efficacy of the approach, microfluidic‐assisted blade coating is used to optimize blending ratios in organic solar cells. Importantly, this novel technology can be easily extended to other solution processable systems that require the formation of solid‐state compositional lateral gradients.  相似文献   
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Congenital melanocytic nevi (CMN) are cutaneous malformations whose prevalence is inversely correlated with projected adult size. CMN are caused by somatic mutations, but epidemiological studies suggest that germline genetic factors may influence CMN development. In CMN patients from the U.K., genetic variants in MC1R, such as p.V92M and loss‐of‐function variants, have been previously associated with larger CMN. We analyzed the association of MC1R variants with CMN characteristics in two distinct cohorts of medium‐to‐giant CMN patients from Spain (N = 113) and from France, Norway, Canada, and the United States (N = 53), similar at the clinical and phenotypical level except for the number of nevi per patient. We found that the p.V92M or loss‐of‐function MC1R variants either alone or in combination did not correlate with CMN size, in contrast to the U.K. CMN patients. An additional case–control analysis with 259 unaffected Spanish individuals showed a higher frequency of MC1R compound heterozygous or homozygous variant genotypes in Spanish CMN patients compared to the control population (15.9% vs. 9.3%; p = .075). Altogether, this study suggests that MC1R variants are not associated with CMN size in these non‐UK cohorts. Additional studies are required to define the potential role of MC1R as a risk factor in CMN development.  相似文献   
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