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121.
A series of 1,3-diazacycloalkyl carboxaldehyde oxime derivatives was synthesized and tested for muscarinic activity in receptor binding assays using [3H]-oxotremorine-M (OXO-M) and [3H]-pirenzepine (PZ) as ligands. Potential muscarinic agonistic or antagonistic properties of the compounds were determined using binding studies measuring their potencies to inhibit the binding of OXO-M and PZ. Preferential inhibition of OXO-M binding was used as an indicator for potential muscarinic agonistic properties; this potential was confirmed in functional studies on isolated organs. 相似文献
122.
RICARDO CRUZ DE CARVALHO ANABELA BERNARDES DA SILVA RENATA SOARES ANDRÉ M. ALMEIDA ANA VARELA COELHO JORGE MARQUES DA SILVA CRISTINA BRANQUINHO 《Plant, cell & environment》2014,37(7):1499-1515
All bryophytes evolved desiccation tolerance (DT) mechanisms during the invasion of terrestrial habitats by early land plants. Are these DT mechanisms still present in bryophytes that colonize aquatic habitats? The aquatic bryophyte Fontinalis antipyretica Hedw. was subjected to two drying regimes and alterations in protein profiles and sucrose accumulation during dehydration and rehydration were investigated. Results show that during fast dehydration, there is very little variation in protein profiles, and upon rehydration proteins are leaked. On the other hand, slow dehydration induces changes in both dehydration and rehydration protein profiles, being similar to the protein profiles displayed by the terrestrial bryophytes Physcomitrella patens (Hedw.) Bruch and Schimp. and, to what is comparable with Syntrichia ruralis (Hedw.) F. Weber and D. Mohr. During dehydration there was a reduction in proteins associated with photosynthesis and the cytoskeleton, and an associated accumulation of proteins involved in sugar metabolism and plant defence mechanisms. Upon rehydration, protein accumulation patterns return to control values for both photosynthesis and cytoskeleton whereas proteins associated with sugar metabolism and defence proteins remain high. The current results suggest that bryophytes from different ecological adaptations may share common DT mechanisms. 相似文献
123.
Graham RD Jones Sabrina DA Koetsier 《The Clinical biochemist. Reviews / Australian Association of Clinical Biochemists》2014,35(4):243-250
Reference intervals are commonly considered to allow for between-laboratory bias. The RCPAQAP Liquid Serum Chemistry Program has collected data on laboratory measurements as well as reference intervals. This allows assessment of the between-laboratory variation in results, reference intervals and the information transmitted by the combination of these factors. For the majority of common chemistry analytes, the between-laboratory variation in reference intervals is greater than the variation in results. Additionally the reference interval variation is generally not related to bias between the results. Use of common reference intervals, either as an average of the current intervals in use, or the intervals proposed by the AACB Harmonisation Group, improved the variation seen in the information produced by different laboratories. 相似文献
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125.
Regina Taurines Christina Schwenck Benjamin Lyttwin Martin Schecklmann Thomas Jans Lennart Reefschläger Julia Geissler Manfred Gerlach Marcel Romanos 《Attention deficit and hyperactivity disorders》2014,6(3):231-239
Findings from research in animal models and humans have shown a clear role for the neuropeptide oxytocin (OT) on complex social behaviors. This is also true in the context of autism spectrum disorder (ASD). Previous studies on peripheral OT concentrations in children and young adults have reported conflicting results with the initial studies presenting mainly decreased OT plasma levels in ASD compared to healthy controls. Our study therefore aimed to further investigate changes in peripheral OT concentrations as a potential surrogate for the effects observed in the central nervous system (CNS) in ASD. OT plasma concentrations were assessed in 19 male children and adolescents with ASD, all with an IQ > 70 (age 10.7 ± 3.8 years), 17 healthy male children (age 13.6 ± 2.1 years) and 19 young male patients with attention deficit hyperactivity disorder (ADHD) as a clinical control group (age 10.4 ± 1.9 years) using a validated radioimmunoassay. Analysis of covariance revealed significant group differences in OT plasma concentrations (F(2, 48) = 9.574, p < 0.001, η 2 = 0.285; plasma concentrations ASD 19.61 ± 7.12 pg/ml, ADHD 8.05 ± 5.49 pg/ml, healthy controls 14.43 ± 9.64 pg/ml). Post hoc analyses showed significantly higher concentrations in children with ASD compared to ADHD (p < 0.001). After Bonferroni correction, there was no significant difference in ASD in comparison with healthy controls (p = 0.132). A significant strong correlation between plasma OT and autistic symptomatology, assessed by the Autism Diagnostic Observation Schedule, was observed in the ASD group (p = 0.013, r = 0.603). Patients with ADHD differed from healthy control children by significantly decreased OT concentrations (p = 0.014). No significant influences of the covariates age, IQ, medication and comorbidity could be seen. Our preliminary results point to a correlation of OT plasma concentrations with autistic symptom load in children with ASD and a modulation of the OT system also in the etiologically and phenotypically overlapping disorder ADHD. Further studies in humans and animal models are warranted to clarify the complex association of the OT system with social impairments as well as stress-related and depressive behavior and whether peripheral findings reflect primary changes of OT synthesis and/or release in relevant areas of the CNS. 相似文献
126.
天童常绿阔叶树种栲树生殖个体大小及其生殖构件特征 总被引:9,自引:0,他引:9
对浙江天童木荷-栲树林内的常绿阔叶树种栲树(Castanopsis fargesii Franch.)的生殖个体大小、生殖构件的分布及其动态变化特征进行了研究。结果表明, 该地区栲树生殖个体的胸径在17~50 cm 间, 平均胸径为31. 2±8.0 cm, 平均年龄约36.3±6.6 年;林缘附近的生殖个体小于木荷-林内。相对稳定的群落和比较丰富的土壤养分条件有利于生殖枝数量和花序数量的增多。栲树生殖个体的数量在两年中变化较大, 部分栲树个体可以在连续年份中生殖。从枝系水平分析:在持续生殖的栲树个体上, 生殖枝数量有明显变化, 并非所有的生殖枝在两年中都可开花或结果, 保持连续生殖的枝系约占48.2%。栲树果序枝数量在连续年份有明显差异(p < 0.01), 而且果序枝上的幼蕾数、果实数量及结实率等都有明显差异(p < 0.05)。 相似文献
127.
Loes M. J. Geelen Astrid F. M. M. Souren Henk W. A. Jans Ad M. J. Ragas 《人类与生态风险评估》2013,19(6):1644-1663
The aim of the present study was to compare the perceived risks of air pollution from industry and traffic in the Moerdijk region in The Netherlands, and to identify the demographic and psychometric variables that are associated with these perceived risks. We sent out a questionnaire and risk perceptions were explored using multiple regression models. The results showed that the perceived risks of industrial air pollution were higher than for those of traffic-related air pollution. The perceived risk of industrial air pollution was associated with other variables than that of traffic. For industry, the psychometric variable affect prevailed. For traffic-related air pollution, the demographic variables age and educational level prevailed, although affect was also apparent. Which source was considered as the major source—traffic or industry—depended on a high risk perception of industrial air pollution, and not on variation in risk perception of traffic-related air pollution. These insights can be used as an impetus for the local risk management process in the Moerdijk region. We recommend that local authorities consider risk perception as one of the targets in local risk management strategies as well. 相似文献
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129.
The precise mechanistic role of the cAMP-dependent protein kinase (cAMP-PK) in cAMP-mediated gene induction remains unclear. Renal epithelial cell mutants were compared to the LLC-PK1 parental cell line for induction of the cAMP-responsive urokinase-type plasminogen activator (uPA) gene, as quantitated by the technique of mRNA solution hybridization. The FIB4 and FIB6 mutants, which possess less than 10% parental cAMP-PK catalytic (C) subunit activity, showed markedly diminished uPA mRNA induction in response to agents elevating intracellular cAMP such as the cAMP analogue 8-bromo-cAMP and the adenylate cyclase-stimulating hormones vasopressin and calcitonin. In contrast, the mutant cells responded to a similar or greater extent than the parental cells in terms of uPA mRNA induction following treatment with the Ca2+/phospholipid-dependent protein kinase activator phorbol 12-myristate 13-acetate (PMA). Elevation of intracellular cAMP was found to induce a translocation of the cAMP-PK C subunit from the perinuclear Golgi region to the nucleus in both parental and mutant cell lines, as shown by immunocytochemical techniques. Results argue for the role of the cAMP-PK C subunit activity and possibly nuclear translocation of the C subunit in cAMP-mediated uPA induction, which is mechanistically distinct from the PMA-stimulated response. 相似文献
130.
Stephan Wullschleger Christoph Jans Clelia Seifert Sarah Baumgartner Christophe Lacroix Bassirou Bonfoh Marc J.A. Stevens Leo Meile 《Systematic and applied microbiology》2018,41(2):65-72
Ten bacterial isolates belonging to the genus Vagococcus were obtained from Malian sour milk fènè produced from spontaneously fermented cow milk. However, these isolates could not be assigned to a species upon initial comparative 16S rRNA gene sequence analysis and were therefore further characterized. Rep-PCR fingerprinting of the isolates yielded four strain clusters represented by strains CG-21T (=DSM 21459T), 24CA, CM21 and 9H. Sequence identity of the 16S rRNA gene of DSM 21459T to its closest relative species Vagococcus penaei was 97.9%. Among the four rep strain clusters, DSM 21459T and 24CA shared highest 16S rRNA gene sequence identity of 99.6% while CM21 and 9H shared 98.6–98.8% with DSM 21459T and V. penaei CD276T. DSM 21459T and 24CA were thus subjected to a polyphasic typing approach. The genome of DSM 21459T featured a G + C content of 34.1 mol% for a 2.17-bp chromosome and a 15-kbp plasmid. Average nucleotide identity (ANI) of DSM 21459T to Vagococcus fluvialis bH819, V. penaei CD276T were 72.88%, 72.63%, respectively. DNA–DNA hybridization (DDH) similarities of strain DSM 21459T to other Vagococcus species were <42.0%. ANI and DDH findings strongly supported the 16S rRNA gene phylogenetic tree delineations. The fatty acid patterns of DSM 21459T was palmitic acid (C 16:0, 24.5%), oleic acid (C 18:1-ω9c, 32.8%), stearic acid (C 18:0, 18.9%). General physiological characterization of DSM 21459T and 24CA were consistent with those of the genus Vagococcus. Strain DSM 21459T and further strains are therefore considered to belong to a novel species, for which the nomenclature Vagococcus teuberi sp. nov. is proposed. The type strain is named CG-21T (=DSM 21459T and LMG 24695T). 相似文献