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71.
Matagne Heutink Marcel WM Post Peter Luthart Lilian EMA Pfennings Catja A Dijkstra Eline Lindeman 《BMC neurology》2010,10(1):96
Background
Most people with a spinal cord injury rate neuropathic pain as one of the most difficult problems to manage and there are no medical treatments that provide satisfactory pain relief in most people. Furthermore, psychosocial factors have been considered in the maintenance and aggravation of neuropathic spinal cord injury pain. Psychological interventions to support people with spinal cord injury to deal with neuropathic pain, however, are sparse. The primary aim of the CONECSI (COping with NEuropathiC Spinal cord Injury pain) trial is to evaluate the effects of a multidisciplinary cognitive behavioural treatment programme on pain intensity and pain-related disability, and secondary on mood, participation in activities, and life satisfaction. 相似文献72.
André M Hidalgo John WM Bastiaansen Barbara Harlizius Hendrik-Jan Megens Ole Madsen Richard PMA Crooijmans Martien AM Groenen 《BMC genetics》2014,15(1):1-13
Background
Androstenone is one of the major compounds responsible for boar taint, a pronounced urine-like odor produced when cooking boar meat. Several studies have identified quantitative trait loci (QTL) for androstenone level on Sus scrofa chromosome (SSC) 6. For one of the candidate genes in the region SULT2A1, a difference in expression levels in the testis has been shown at the protein and RNA level.Results
Haplotypes were predicted for the QTL region and their effects were estimated showing that haplotype 1 was consistently related with a lower level, and haplotype 2 with a higher level of androstenone. A recombinant haplotype allowed us to narrow down the QTL region from 3.75 Mbp to 1.94 Mbp. An RNA-seq analysis of the liver and testis revealed six genes that were differentially expressed between homozygotes of haplotypes 1 and 2. Genomic sequences of these differentially expressed genes were checked for variations within potential regulatory regions. We identified one variant located within a CpG island that could affect expression of SULT2A1 gene. An allele-specific expression analysis in the testis did not show differential expression between the alleles of SULT2A1 located on the different haplotypes in heterozygous animals. However a synonymous mutation C166T (SSC6: 49,117,861 bp in Sscrofa 10.2; C/T) was identified within the exon 2 of SULT2A1 for which the haplotype 2 only had the C allele which was higher expressed than the T allele, indicating haplotype-independent allelic-imbalanced expression between the two alleles. A phylogenetic analysis for the 1.94 Mbp region revealed that haplotype 1, associated with low androstenone level, originated from Asia.Conclusions
Differential expression could be observed for six genes by RNA-seq analysis. No difference in the ratio of C:T expression of SULT2A1 for the haplotypes was found by the allele-specific expression analysis, however, a difference in expression between the C over T allele was found for a variation within SULT2A1, showing that the difference in androstenone levels between the haplotypes is not caused by the SNP in exon 2. 相似文献73.
An analysis of restriction fragment length polymorphism (RFLP) using eight
residential insertion sequence (IS) elements as hybridization probes
reveals that the genome of resting bacteria is more dynamic than it was
long believed. Escherichia coli strains stored in agar stabs for up to 30
yr accumulate a genetic variation which is correlated to time of storage.
This spontaneous mutagenesis is often IS-specific, with particularly high
activity for IS5, and thus suggests that transpositional DNA rearrangements
are a major cause for the observed genetic polymorphism. The RFLP patterns
indicate a burst of IS30 transposition to occur occasionally. Mutation rate
is estimated by two different methods to roughly 10(-5) IS-related DNA
rearrangements per bacterial chromosome per hour of storage for the eight
IS elements studied. A pedigree derived from the RFLP data reveals that
populations had evolved independently in each stab and showed no signs of
convergence. Relics of an assumed ancestral population were still present
in the stab cultures, but the elder stabs provided mostly mutants. These
results indicate that cells placed under nutritional deprivation might have
a highly plastic genome and suggest that such plasticity might play an
adaptive role.
相似文献
74.
H T Hertzberg 《American journal of physical anthropology》1966,25(3):335-336
This note presents working drawings and a photograph of a tool that facilitates immediate repair of sliding calipers damaged during anthropometric surveys. 相似文献
75.
Oxidative phosphorylation and proton translocation in membrane vesicles prepared from Escherichia coli 总被引:19,自引:0,他引:19
This paper reports physical-chemical properties of proteins L7 and L12 from E. coli 50 S subunits. Evidence is presented that these two proteins behave in their native state as a dimer of molecular weight 24000. From sedimentation velocity and intrinsic viscosity data the actual frictional ratio of the dimer has been obtained revealing an asymmetric particle which can be described as a rod with cell dimensions of L = 130 Å and a diameter of D = 17.0 Å. From small X-ray scattering the radius of gyration (Rg = 37.0 Å), the thickness factor, and the degree of hydration were determined. This indicates that the extended shape of the dimer is due to the asymmetry of the molecule and not to the hydration. 相似文献
76.
Sean WM Collins Xisto Martins Andrew Mitchell Awegechew Teshome John T Arnason 《Journal of ethnobiology and ethnomedicine》2007,3(1):1-10
In recent years, diverse scholars have addressed the issue of the chemosensory perceptions associated with traditional medicines, nevertheless there is still a distinct lack of studies grounded in the social sciences and conducted from a cross-cultural, comparative perspective. In this urban ethnobotanical field study, 254 informants belonging to the Gujarati, Kashmiri and English ethnic groups and living in Western Yorkshire in Northern England were interviewed about the relationship between taste and medicinal perceptions of five herbal drugs, which were selected during a preliminary study. The herbal drugs included cinnamon (the dried bark of Cinnamomum verum, Lauraceae), mint (the leaves of Mentha spp., Lamiaceae), garlic (the bulbs of Allium sativum, Alliaceae), ginger (the rhizome of Zingiber officinale, Zingiberaceae), and cloves (the dried flower buds of Syzygium aromaticum, Myrtaceae). The main cross-cultural differences in taste perceptions regarded the perception the perception of the spicy taste of ginger, garlic, and cinnamon, of the bitter taste of ginger, the sweet taste of mint, and of the sour taste of garlic. The part of the study of how the five selected herbal drugs are perceived medicinally showed that TK (Traditional Knowledge) is widespread among Kashmiris, but not so prevalent among the Gujarati and especially the English samples. Among Kashmiris, ginger was frequently considered to be helpful for healing infections and muscular-skeletal and digestive disorders, mint was chosen for healing digestive and respiratory troubles, garlic for blood system disorders, and cinnamon was perceived to be efficacious for infectious diseases. Among the Gujarati and Kashmiri groups there was evidence of a strong link between the bitter and spicy tastes of ginger, garlic, cloves, and cinnamon and their perceived medicinal properties, whereas there was a far less obvious link between the sweet taste of mint and cinnamon and their perceived medicinal properties, although the link did exist among some members of the Gujarati group. Data presented in this study show how that links between taste perceptions and medicinal uses of herbal drugs may be understood as bio-cultural phenomena rooted in human physiology, but also constructed through individual experiences and culture, and that these links can therefore be quite different across diverse cultures. 相似文献
77.
Multilocus DNA fingerprinting methods have been used extensively to address genetic issues in wildlife populations. Hypotheses concerning population subdivision and differing levels of diversity can be addressed through the use of the similarity index (S), a band-sharing coefficient, and many researchers construct hypothesis tests with S based on the work of Lynch. It is shown in the present study, through mathematical analysis and through simulations, that estimates of the variance of a mean S based on Lynch's work are downwardly biased. An unbiased alternative is presented and mathematically justified. It is shown further, however, that even when the bias in Lynch's estimator is corrected, the estimator is highly imprecise compared with estimates based on an alternative approach such as 'parametric bootstrapping' of allele frequencies. Also discussed are permutation tests and their construction given the interdependence of Ss which share individuals. A simulation illustrates how some published misuses of these tests can lead to incorrect conclusions in hypothesis testing. 相似文献
78.
79.
Katherine Widdowson Hong Nie Anthony J. Jurewicz Robert P. Hertzberg Henry M. Sarau James J. Foley JudithAnn Lee John R. White Daniel F. Veber 《Letters in Peptide Science》1998,5(2-3):235-239
In an effort to determine the role of the acidic group in the receptor binding of N-(2-hydroxy-4-nitrophenyl)-N-(phenyl) urea, an interleukin-8B receptor antagonist, its binding and that of several analogs was measured as a function of pH. These titrations indicate that these ureas bind most strongly in their anionic form. Studies of antagonists, with different acidities, demonstrated that the greatest change in binding of each urea occurred around the pKa of the compound being examined. The studies suggest that the increase in binding of the antagonists at higher pH is a result of the increased negative charge on the compounds rather than the effects of pH on the receptor or radioligand. 相似文献
80.
Comparative analysis of the major polypeptides from liver gap junctions and lens fiber junctions 总被引:19,自引:10,他引:9 下载免费PDF全文
Gap junctions from rat liver and fiber junctions from bovine lens have similar septilaminar profiles when examined by thin-section electron microscopy and differ only slightly with respect to the packing of intramembrane particles in freeze-fracture images. These similarities have often led to lens fiber junctions being referred to as gap junctions. Junctions from both sources were isolated as enriched subcellular fractions and their major polypeptide components compared biochemically and immunochemically. The major liver gap junction polypeptide has an apparent molecular weight of 27,000, while a 25,000-dalton polypeptide is the major component of lens fiber junctions. The two polypeptides are not homologous when compared by partial peptide mapping in SDS. In addition, there is not detectable antigenic similarity between the two polypeptides by immunochemical criteria using antibodies to the 25,000-dalton lens fiber junction polypeptide. Thus, in spite of the ultrastructural similarities, the gap junction and the lens fiber junction are comprised of distinctly different polypeptides, suggesting that the lens fiber junction contains a unique gene product and potentially different physiological properties. 相似文献