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641.
Lucie Jiraska Beatrix Jones Sarah J. Knight Jed Lennox Matthew R. Goddard 《Environmental microbiology》2023,25(12):3655-3670
Within geographic regions, the existing data suggest that physical habitat (bark, soil, etc.) is the strongest factor determining agroecosystem microbial community assemblage, followed by geographic location (site), and then management regime (organic, conventional, etc.). The data also suggest community similarities decay with increasing geographic distance. However, integrated hypotheses for these observations have not been developed. We formalized and tested such hypotheses by sequencing 3.8 million bacterial 16S, fungal ITS2 and non-fungal eukaryotic COI barcodes deriving from 108 samples across two habitats (soil and bark) from six vineyards sites under conventional or conservation management. We found both habitat and site significantly affected community assemblage, with habitat the stronger for bacteria only, but there was no effect of management. There was no evidence for community similarity distance–decay within sites within each habitat. While communities significantly differed between vineyard sites, there was no evidence for between site community similarity distance–decay apart from bark bacterial communities, and no correlations with soil and bark pH apart from soil bacterial communities. Thus, within habitats, vineyard sites represent discrete biodiversity islands, and while bacterial, fungal and non-fungal eukaryotic biodiversity mostly differs between sites, the distance by which they are separated does not define how different they are. 相似文献
642.
The most debilitating feature of cystic fibrosis (CF) disease is uncontrolled inflammation of respiratory epithelium. The relationship between the commonest mutated form of CFTR (F508del or ΔF508) and inflammation has not yet been elucidated. Here, we present a new paradigm suggesting that CFTR can interact with intra-epithelial IgG, establishing a direct link between normal CFTR and the immune system. Further, our data show that the amino-acid sequence local to F508 can bind IgG with high affinity, dependent on F508, such that loss of F508 abolishes this link both in vitro and in the intact cell. 相似文献
643.
John Goddard 《African Journal of Ecology》1968,6(1):1-18
Food preferences of two discrete black rhinoceros (Diceros bicornis L.) populations were studied in northern Tanzania from 1964–1966 Feeding rhinoceros were watched for a period of one hour, and the plants which they selected and rejected were identified, either as they were feeding or when they had moved on. A technique was used which provided an indication of the relative importance of certain plants in the diet. Observations were made in six different habitat types used by the rhinoceros during the wet and dry seasons. A total of 307 hours was spent actually watching feeding rhinoceros. During this period they were observed eating 191 plant species from 49 botanical families. In all habitat types rhinoceros consume a wide variety of the spectrum of plants available, but are highly selective for herbs and shrubs. At certain periods of the year stenophagous characteristics are apparent, and the species shows a marked preference for legumes. Grasses make up a small proportion of the diet. 相似文献
644.
Rosanne M. Orr Florence I. Raynaud Phyllis M. Goddard Ian R. Judson Terry Beck Bob Bryant 《Nucleosides, nucleotides & nucleic acids》2013,32(7-9):1699-1702
Abstract G3139, an 18mer phosphorothioate (S-labeled), was administered to mice by single i.v. bolus or continuous S.C. infusion. The latter schedule resulted in reduced liver metabolism and urinary excretion together with greater tissue accumulation, in particular to the liver, kidney and bone marrow, probably reflecting the dose received. 相似文献
645.
646.
M. R. S. Fortes K. Kemper S. Sasazaki A. Reverter J. E. Pryce W. Barendse R. Bunch R. McCulloch B. Harrison S. Bolormaa Y. D. Zhang R. J. Hawken M. E. Goddard S. A. Lehnert 《Animal genetics》2013,44(6):636-647
A putative functional mutation (rs109231213) near PLAG1 (BTA14) associated with stature was studied in beef cattle. Data from 8199 Bos taurus, Bos indicus and Tropical Composite cattle were used to test the associations between rs109231213 and various phenotypes. Further, 23 496 SNPs located on BTA14 were tested for association with these phenotypes, both independently and fitted together with rs109231213. The C allele of rs109231213 significantly increased hip height, weight, net food intake, age at puberty in males and females and decreased IGF‐I concentration in blood and fat depth. When rs109231213 was fitted as a fixed effect in the model, there was an overall reduction in associations between other SNPs and these traits but some SNPs remained associated (P < 10?4). Frequency of the mutant C allele of rs109231213 differed among B. indicus (0.52), B. taurus (0.96) and Tropical Composite (0.68). Most chromosomes carrying the C allele had the same surrounding 10 SNP haplotype, probably because the C allele was introgressed into Brahman from B. taurus cattle. A region of reduced heterozygosity surrounds the C allele; this is small in B. taurus but 20 Mb long in Brahmans, indicating recent and strong selection for the mutant allele. Thus, the C allele appears to mark a mutation that has been selected almost to fixation in the B. taurus breeds studied here and introduced into Brahman cattle during grading up and selected to a frequency of 0.52 despite its negative effects on fertility. 相似文献
647.
648.
Human clinical and psychophysical observations suggest that the taste
system is able to compensate for losses in peripheral nerve input, since
patients do not commonly report decrements in whole mouth taste following
chorda tympani nerve damage or anesthesia. Indeed, neurophysiological data
from the rat nucleus of the solitary tract (NST) suggests that a release of
inhibition (disinhibition) may occur centrally following chorda tympani
nerve anesthesia. Our purpose was to study this possibility further. We
recorded from 59 multi- and single- unit taste-responsive sites in the rat
NST before, during and after recovery from chorda tympani nerve anesthesia.
During anesthesia, average anterior tongue responses were eliminated but no
compensatory increases in palatal or posterior tongue responses were
observed. However, six individual sites displayed increased taste
responsiveness during anesthesia. The average increase was 32.9%.
Therefore, disinhibition of taste responses was observed, but infrequently
and to a small degree in the NST At a subset of sites, chorda
tympani-mediated responses decreased while greater superficial
petrosal-mediated responses remained the same during anesthesia. Since this
effect was accompanied by a decrease in spontaneous activity, we propose
that taste compensation may result in part by a change in signal-to-noise
ratio at a subset of sites.
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