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31.
Abstract: The anthelmintic macrolide, ivermectin, enhances the binding of benzodiazepine agonist ([3H]-diazepam) and antagonist ([3H]β-carboline ethyl ester) ligands to rat cortical and cerebellar membrane preparations. Enhancement of benzodiazepine agonist binding is partially additive with that of γ-aminobutyric acid (GABA) and is inhibited by etazolate, bicuculline, and the steroid GABA antagonist R5135. Ivermectin-stimulated benzodiazepine antagonist binding is enhanced by bicuculline and inhibited by GABA and etazolate. The modulatory effects of bicuculline are chloride-dependent. The stimulatory effects of ivermectin, while quantitatively different in cortex and cerebellum, are qualitatively similar in both brain regions and are reduced in the presence of chloride. Ivermectin effects on benzodiazepine ligand binding to the benzodiazepine receptor complex and the differences in the effects of GABA, bicuculline, and R5135 on ivermectin-stimulated agonist and antagonist binding may provide evidence for distinct differences in the recognition sites for the two classes of benzodiazepine receptor ligand and their interactions with other components of the receptor complex.  相似文献   
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The aim of this study was to compare the effects of static stretching, proprioceptive neuromuscular facilitation (PNF) stretching and Mulligan technique on hip flexion range of motion (ROM) in subjects with bilateral hamstring tightness. A total of 40 students (mean age: 21.5±1.3 years, mean body height: 172.8±8.2 cm, mean body mass index: 21.9±3.0 kg · m-2) with bilateral hamstring tightness were enrolled in this randomized trial, of whom 26 completed the study. Subjects were divided into 4 groups performing (I) typical static stretching, (II) PNF stretching, (III) Mulligan traction straight leg raise (TSLR) technique, (IV) no intervention. Hip flexion ROM was measured using a digital goniometer with the passive straight leg raise test before and after 4 weeks by two physiotherapists blinded to the groups. 52 extremities of 26 subjects were analyzed. Hip flexion ROM increased in all three intervention groups (p<0.05) but not in the no-intervention group after 4 weeks. A statistically significant change in initial–final assessment differences of hip flexion ROM was found between groups (p<0.001) in favour of PNF stretching and Mulligan TSLR technique in comparison to typical static stretching (p=0.016 and p=0.02, respectively). No significant difference was found between Mulligan TSLR technique and PNF stretching (p=0.920). The initial–final assessment difference of hip flexion ROM was similar in typical static stretching and no intervention (p=0.491). A 4-week stretching intervention is beneficial for increasing hip flexion ROM in bilateral hamstring tightness. However, PNF stretching and Mulligan TSLR technique are superior to typical static stretching. These two interventions can be alternatively used for stretching in hamstring tightness.  相似文献   
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Aims were to estimate the extent of genetic heterogeneity in environmental variance. Data comprised 99 535 records of 35-day body weights from broiler chickens reared in a controlled environment. Residual variance within dam families was estimated using ASREML, after fitting fixed effects such as genetic groups and hatches, for each of 377 genetically contemporary sires with a large number of progeny (> 100 males or females each). Residual variance was computed separately for male and female offspring, and after correction for sampling, strong evidence for heterogeneity was found, the standard deviation between sires in within variance amounting to 15–18% of its mean. Reanalysis using log-transformed data gave similar results, and elimination of 2–3% of outlier data reduced the heterogeneity but it was still over 10%. The correlation between estimates for males and females was low, however. The correlation between sire effects on progeny mean and residual variance for body weight was small and negative (-0.1). Using a data set bigger than any yet presented and on a trait measurable in both sexes, this study has shown evidence for heterogeneity in the residual variance, which could not be explained by segregation of major genes unless very few determined the trait.  相似文献   
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The macrocyclic antibiotic LY333328 has been evaluated as a chiral selector for the enantioseparation of nine dansylated amino acids. This macrocyclic glycopeptide was used as a chiral mobile phase additive (CMPA) in conjunction with narrow bore high‐performance liquid chromatography (HPLC). The key mobile phase parameters of LY333328 concentration and buffer pH were varied, along with variations in stationary phases consisting of C8, phenyl, cyano, and silica. After observing and plotting changes in retention and resolution based on corresponding variation in these parameters, a better understanding of the behavior of this chiral selector was obtained. The pKa values of the dansyl amino acid analytes and LY333328 were measured and used to gain a better understanding of the microenvironment in which these enantioseparations occur. Optimized conditions resulted in the baseline separation of eight of nine dansyl amino acids. Chirality 11:75–81, 1999. © 1999 Wiley‐Liss, Inc.  相似文献   
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Circular RNAs (circRNAs) are novel noncoding RNAs and play crucial roles in various biological processes. However, little is known about the functions of circRNAs in osteogenic differentiation. The current study aimed to investigate the differential expression of circRNAs in rat dental follicle cells (rDFCs) during osteogenic differentiation, identified by RNA high-throughput sequencing and quantitative real-time polymerase chain reaction. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses were performed to further explore the biofunctions of circRNA biofunctions. Two hundred sixty-six differentially-expressed circRNAs that are involved in several important signaling pathways, including mitogen-activated protein kinases (MAPK) and transforming growth factor-β (TGF-β) signaling pathways were revealed. Among these, circFgfr2 and its predicted downstream targets, miR-133 and BMP6 (bone morphogenetic protein-6), were identified both in vivo and in vitro. For further validation, circFgfr2 was overexpressed in rDFCs, the results showed that the expression of miR-133 was downregulated and the expression of BMP6 was upregulated. Taken together, the results revealed the circRNA expression profiles and indicated the importance of circRNAs of rDFCs. In addition, circFgfr2 might promote osteogenesis by controlling miR-133/BMP6, which is a potential new target for the manipulation of tooth regeneration and bone formation.  相似文献   
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1H-N.m.r. spectroscopy was used to elucidate the primary structures of the carbohydrate moiety attached to asparagine at residue 53 in the first domain of turkey ovomucoid, a serine proteinase inhibitor. The carbohydrate moiety is a heterogeneous mixture of three structurally closely related complex-type oligosaccharides. Of the total carbohydrate moiety, 61% is tetra-antennary with terminal galactose and with an intersecting N-acetylglucosamine, and containing an additional N-acetylglucosamine (10') attached to mannose (4'). Another 23% is tri-antennary with terminal galactose and with an intersecting N-acetylglucosamine. The remaining 16% is tri-antennary with terminal galactose (6 and 8 only), with an intersecting N-acetylglucosamine.  相似文献   
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Briza maxima (quaking grass) is a cosmopolitan grass common to Europe and North and South America. It grows in disturbed soils and on roadsides. The hemispherical caryopsis is embedded between a leaflike lemma and flattened palea. The embryo is of the festucoid type. The scutellum shows two surrounding ridges at the edge of the scutellum/endosperm boundary, and has lateral lobes. A broad epiblast extends toward the embryo apex and is continuous with the dorsal surface of the coleorhiza. The single-layered aleurone surrounds the starchy endosperm and is discontinuous around the embryo. The caryopsis coat is thin, except at the placental pad where it is thickened by the pigment strand and the nucellar projection.  相似文献   
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12S ribosomal RNA (rRNA) gene sequences from a suite of mammalian taxa (13 placentals, 4 marsupials, 1 monotreme), for which phylogenetic relationships are well established based on independent criteria, were employed to study the evolution of this gene. Phylogenetic analysis of 12S sequences produces a phylogeny that agrees with expectations. Base composition provides evidence for directional symmetrical substitution pressure in loops; in stems, base composition is much more even. Rates of nucleotide substitution are lower in stems than loops. Patterns of nucleotide substitution show an overall preference for transitions over transversions, with this difference more profound in stems than loops. Among different transversion pathways, there is a wide range of transformation frequencies. An analysis of compensatory substitutions shows that there is strong evidence for their occurrence and that a weighting factor of 0.61 should be applied in phylogenetic analyses to account for the dependence of mutations at stem positions relative to positions where changes are independent. Among stem variables (i.e., stem length, interaction distance, substitution rates, G+C content, and the percentage of bases that are paired), several significant correlations were discovered, but stem length and interaction distance are uncorrelated with other variables.   相似文献   
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