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81.
The interaction of chicken spleen cells with sheep erythrocytes coated with chicken antibody (EA complexes) was studied using a rosette assay. The results reported in this paper indicate that subpopulations of chicken lymphocytes, monocytes, and heterophils have a receptor for EA. The formation of rosettes between chicken lymphoid cells and sheep erythrocytes (SRBC) was dependent upon the concentration of antibody used to sensitize the SRBC. In a developmental study of rosette-forming lymphocytes (RFL), the bursa was the first site of appearance of large numbers of RFL. The percentage of RFL in the bursa reached a peak at 17 days of embryonic life, and declined to a low by hatching. The percentage of RFL in the spleen, however, began to increase at the time of hatching and by 6 weeks of age the spleen far surpassed the bursa in percentage RFL. At no age were significant numbers of RFL detected in the thymus. 相似文献
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84.
Benjamin Hing Patricia Braun Zachary A. Cordner Erin R. Ewald Laura Moody Melissa McKane 《Epigenetics》2018,13(6):627-641
Chronic stress resulting from prolonged exposure to negative life events increases the risk of mood and anxiety disorders. Although chronic stress can change gene expression relevant for behavior, molecular regulators of this change have not been fully determined. One process that could play a role is DNA methylation, an epigenetic process whereby a methyl group is added onto nucleotides, predominantly cytosine in the CpG context, and which can be induced by chronic stress. It is unknown to what extent chronic social defeat, a model of human social stress, influences DNA methylation patterns across the genome. Our study addressed this question by using a targeted-capture approach called Methyl-Seq to investigate DNA methylation patterns of the dentate gyrus at putative regulatory regions across the mouse genome from mice exposed to 14 days of social defeat. Findings were replicated in independent cohorts by bisulfite-pyrosequencing. Two differentially methylated regions (DMRs) were identified. One DMR was located at intron 9 of Drosha, and it showed reduced methylation in stressed mice. This observation replicated in one of two independent cohorts. A second DMR was identified at an intergenic region of chromosome X, and methylation in this region was increased in stressed mice. This methylation difference replicated in two independent cohorts and in Major Depressive Disorder (MDD) postmortem brains. These results highlight a region not previously known to be differentially methylated by chronic social defeat stress and which may be involved in MDD. 相似文献
85.
Molecular characterization of major histocompatibility complex (B) haplotypes in broiler chickens 总被引:2,自引:0,他引:2
In Leghorn (laying) chickens, susceptibility to a number of infectious diseases is strongly associated with the major histocompatibility ( B ) complex. Nucleotide sequence data have been published for six class I ( B-F ) alleles and for class II ( B-Lβ ) alleles or isotypes from 17 Leghorn haplotypes. It is not known if classical B-L or B-F alleles in broilers are identical, at the sequence level, to any Leghorn alleles. This report describes molecular and immunogenetic characterization of two haplotypes from commercial broiler breeder chickens that were originally identified by serology as a single haplotype, but were differentiated serologically in the present work. The two haplotypes, designated B A4 and B A4variant , shared identical B-G restriction fragment length polymorphism patterns, but differed in one B-Lβ fragment that cosegregated with the serological B haplotype. Furthermore, the nucleotide sequences of the highly variable exons of an expressed B-LβII family gene and B-F gene from the two haplotypes were markedly different from each other. Both the B-LβII family and B-F gene sequences from the B A4 haplotype were identical to the sequences obtained from the reference B 21 haplotype in Leghorns; however, in the B A4 haplotype the B-Lβ 21 and B-F 21 alleles were in linkage with B-G alleles that were not G 21 . The nucleotide sequences from B A4variant were unique among the reported chicken B-LβII family and B-F alleles. 相似文献
86.
Continuous micropropagation of juvenile larch from different species via adventitious bud formation 总被引:4,自引:0,他引:4
A continuous propagation of juvenile larch in vitro was based on adventitious bud formation and different cytokinin combinations
were tested concerning their effectiveness to induce elongation of adventitious buds. Zeatin (1.5 mg dm-3) combined with kinetin
(0.15 mg dm-3) was found to be the best. Development and elongation of buds was achieved on a modified LP-medium. Using this
system it was possible to propagate different larchspecies (Larix decidua, L. gmelinii and L. sukaczewii f. multiramosus)
continuously. Shoots were successfully rooted and transferred to the soil.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
87.
Jung JA Jhang E. John Staba Jung Yun Kim 《In vitro cellular & developmental biology. Plant》1974,9(4):253-259
Summary Roots, stems, or leaves of American (Panax quinquefolium) and Korean (Panax ginsing) ginseng were grown as callus or supension tissue cultures. Tissue cultures ofP. ginseng would occasionally form plantlets. The fundamental chemical composition, inorganic analysis, and saponin (panaquilin) content
of American and Korean ginseng plants and tissue cultures were determined. The crude saponin content is very similar to, but
approximately one-half (1.3%, fresh weight) of that present in ginseng roots. Two-dimensional thin layer chromatographic analysis
revealed minor differences in the panaquilins present in American and Korean ginseng tissue cultures. The sapogenin, panaxadiol,
was isolated from Korean ginseng callus. 相似文献
88.
89.
JA Nboyine S Boyer D Saville MJ Smith SD Wratten 《New Zealand journal of zoology.》2016,43(4):336-350
The endemic New Zealand ground wētā (Hemiandrus sp. ‘promontorius’) has a Naturally Uncommon conservation status. This is because of the paucity of information on its density and distribution. Here, the biology, density and distribution of a population of this wētā found in and around vineyards in the Awatere Valley, Marlborough was studied. Wētā density was assessed in vineyards, paddocks and shrublands in this valley. Soil moisture, penetration resistance, pH and organic matter were recorded at locations with and without wētā. Wētā density in vineyards was significantly higher than in either paddocks or shrub habitats. In vineyards, the density of this insect was significantly higher under-vines than in the inter-rows. Higher numbers of this wētā were found in moist soils that required lower force to burrow. Females laid an average of 55 eggs between March and April, which hatched in September. These findings highlight the intersection between agriculture and conservation. 相似文献
90.
Distinguishing morphologically cryptic taxa, by definition, requires genetic data such as DNA sequences. However, DNA sequences may not be obtained easily for taxa from remote sites. Here we provide the details of a high-resolution melt-curve-based method using taxon-specific primers that can distinguish two taxa of Adélie penguins, and that will be usable in Antarctica when combined with some of the newly developed field-deployable thermal cyclers. We suggest that the wider adoption of field-deployable polymerase-chain-reaction-based techniques will enable faster assignation of haplotype to individuals in situ, and so allow the targeting of observations and sample collection to specimens relevant to the research question. Targeting individuals will also reduce the need to repeatedly handle animals and reduce the time and travel required to complete field work. 相似文献