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1.
The effect of neurotensin on submaximally-stimulated hepatobiliary and pancreatic secretion was studied in 6 healthy subjects. An intravenous infusion of neurotensin 1.4 ± 0.3 pmol/kg/min, designed to reproduce plasma neurotensin immunoreactivity levels within the physiological range, produced a significant increase in pancreatic bicarbonate output. Plasma concentrations of pancreatic polypeptide rose by 83 ± 16 pmol/l and were associated with a small reduction in trypsin, but no significant change in bilirubin outputs. 相似文献
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Rezende Renan de Souza Kroth Nádia Capitanio Bruna Maria Lima-Rezende Cássia Alves Cassol Angélica Soligo Cozzer Gilberto Dinis Baldissera Ronei Breaux Jennifer Ann Albeny-Simões Daniel 《Limnology》2020,21(3):275-285
Limnology - Aquatic macroinvertebrate communities are dependent on intrinsic environmental characteristics and biological interactions in microhabitat systems. We investigated the... 相似文献
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AB Zarafi AM Emechebe AD Akpa O Alabi 《Archives Of Phytopathology And Plant Protection》2013,46(4):261-268
Pearl millet downy mildew (DM) incidence, severity and yield losses of two pearl millet varieties (local and improved) due to the disease were determined in the field. Significant differences in the disease incidence and severity were recorded in the plots sown with metalaxyl-treated seeds and those sown with non-treated seeds, indicating the efficacy of the fungicide on the fungus. Yield losses due to non-treatment of seeds with metalaxyl was 40.88 and 45.39% in a local variety and 43.00 and 18.60% in an improved variety in the 2000 and 2001 cropping seasons respectively. Significant differences between plots sown with metalaxyl-treated and those sown with non-treated seeds were obtained for other yield components such as 1000-grains weight, panicle length and weight. 相似文献
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Zaida Araujo Francesca Giampietro María de los Angeles Bochichio Andrea Palacios Jenifer Dinis Jaime Isern Jacobus Henry de Waard Elsa Rada Rafael Borges Carlos Fernández de Larrea Angel Villasmil Magnolia Vanegas Jose Antonio Enciso-Moreno Manuel Alfonso Patarroyo 《Memórias do Instituto Oswaldo Cruz》2013,108(2):131-139
The goal of this study was to demonstrate the usefulness of an enzyme-linked immunosorbent assay (ELISA) for the serodiagnosis of pulmonary tuberculosis (PTB) and extrapulmonary TB (EPTB). This assay used 20 amino acid-long, non-overlapped synthetic peptides that spanned the complete Mycobacterium tuberculosis ESAT-6 and Ag85A sequences. The validation cohort consisted of 1,102 individuals who were grouped into the following five diagnostic groups: 455 patients with PTB, 60 patients with EPTB, 40 individuals with non-EPTB, 33 individuals with leprosy and 514 healthy controls. For the PTB group, two ESAT-6 peptides (12033 and 12034) had the highest sensitivity levels of 96.9% and 96.2%, respectively, and an Ag85A-peptide (29878) was the most specific (97.4%) in the PTB groups. For the EPTB group, two Ag85A peptides (11005 and 11006) were observed to have a sensitivity of 98.3% and an Ag85A-peptide (29878) was also the most specific (96.4%). When combinations of peptides were used, such as 12033 and 12034 or 11005 and 11006, 99.5% and 100% sensitivities in the PTB and EPTB groups were observed, respectively. In conclusion, for a cohort that consists entirely of individuals from Venezuela, a multi-antigen immunoassay using highly sensitive ESAT-6 and Ag85A peptides alone and in combination could be used to more rapidly diagnose PTB and EPTB infection. 相似文献
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Marchal LM van de Laar AM Goetheer E Schimmelpennink EB Bergsma J Beeftink HH Tramper J 《Biotechnology and bioengineering》1999,63(3):344-355
The hydrolysis of starch to low-molecular-weight products (normally characterised by their dextrose equivalent (DE), which is directly related to the number-average molecular mass) was studied at different temperatures. Amylopectin potato starch, lacking amylose, was selected because of its low tendency towards retrogradation at lower temperatures. Bacillus licheniformis alpha-amylase was added to 10% [w/w] gelatinised starch solutions. The hydrolysis experiments were done at 50, 70, and 90 degrees C. Samples were taken at defined DE values and these were analysed with respect to their saccharide composition. At the same DE the oligosaccharide composition depended on the hydrolysis temperature. This implies that at the same net number of bonds hydrolysed by the enzyme, the saccharide composition was different. The hydrolysis temperature also influenced the initial overall molecular-weight distribution. Higher temperatures led to a more homogenous molecular weight distribution. Similar effects were observed for alpha-amylases from other microbial sources such as Bacillus amyloliquefaciens and Bacillus stearothermophilus. Varying the pH (5.1, 6.2, and 7.6) at 70 degrees C did not significantly influence the saccharide composition obtained during B. licheniformis alpha-amylase hydrolysis. The underlying mechanisms for B. licheniformis alpha-amylase were studied using pure linear oligosaccharides, ranging from maltotriose to maltoheptaose as substrates. Activation energies for the hydrolysis of individual oligosaccharides were calculated from Arrhenius plots at 60, 70, 80, and 90 degrees C. Oligosaccharides with a degree of polymerisation exceeding that of the substrate could be detected. The contribution of these oligosaccharides increased as the degree of polymerisation of the substrate decreased and the temperature of hydrolysis increased. The product specificity decreased with increasing temperature of hydrolysis, which led to a more equal distribution between the possible products formed. Calculations with the subsite map as determined for the closely related alpha-amylase from B. amyloliquefaciens reconfirmed this finding of a decreased substrate specificity with increased temperature of hydrolysis. Copyright 1999 John Wiley & Sons, Inc. 相似文献
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Peroxynitrite has been shown to modify low-density lipoproteins (LDL) into a form recognized by the macrophage scavenger receptor, suggesting that it may play a significant role in atherogenesis. Considering that the mechanisms underlying LDL modifications by this agent have not been well elucidated, the aim of this study was to characterize the chemical modifications of either the lipid or the protein moieties mediated by synthesized peroxynitrite (preformed) or formed in situ by SIN-1, and evaluate the protective effects of some dietary phenolic acids. Preformed peroxynitrite does not induce LDL lipid peroxidation, as assessed either by formation of conjugated diene isomers or degradation of fatty acids and cholesteryl esters, although a rapid loss of alpha-tocopherol content occurs. Also, peroxynitrite formed in situ induces only a slight lipid oxidation. In contrast, under conditions where the LDL lipid moiety is not significantly oxidized, peroxynitrite either preformed or formed in situ rapidly elicit significant LDL apoprotein modifications, as evaluated by an increase in carbonyl groups formation and by great decrease in intrinsic tryptophan and thiol groups, in a concentration-dependent manner, that are accompanied by an increase in the LDL net negative charge, leading to an increase in electrophoretic mobility. Phenolic acids, namely caffeic, chlorogenic and ferulic, inhibit all these processes in a concentration dependent way, being the catechols the most efficient. UV spectral analysis of phenols upon interaction with peroxynitrite suggest that, in our assay conditions, such protection is related with the scavenging of this agent by either electron donation for the catechols, caffeic and chlorogenic acids, or nitration for the monophenol ferulic acid. Our data point that in contrast with other physiological oxidants, as ferrylmyoglobin or copper, peroxynitrite triggers the rapid damage to LDL primarily by protein and not lipid oxidation, and that such process is inhibited by dietary phenolic derivatives of cinnamic acids. 相似文献