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1.
《Saudi Journal of Biological Sciences》2017,24(8):1879-1883
ObjectiveTo study the early predictive value of cord blood bilirubin and dynamic monitoring of transcutaneous bilirubin for hyperbilirubinemia of newborns.Methods389 newborns delivered from June 2014 to December 2015 were enrolled as the research subjects; detailed records were made about the general data of newborns and mothers, and after cord blood bilirubin being graded, the incidence of hyperbilirubinemia was counted, and the prediction efficiency of cord blood bilirubin was analyzed by receiver operator characteristic (ROC) curve. At the same time, the transcutaneous bilirubin was detected continuously when the neonate was born and 24 h, 48 h and 72 h after birth, and the relativity between transcutaneous bilirubin at 72 h and serum bilirubin was analyzed.ResultsNo significant difference was found in the hyperbilirubinemia group and the non-hyperbilirubinemia group concerning general data of the newborns and their mothers. With the concentration of cord blood bilirubin increased, the incidence of hyperbilirubinemia also increased; separate prediction of hyperbilirubinemia by cord blood bilirubin showed a sensitivity and specificity of 71.4% and 65.6% respectively, and they need further dynamic monitoring. The daily mean of transcutaneous bilirubin in hyperbilirubinemia group was significantly higher than that in non-hyperbilirubinemia group at 24 h, 48 h and 72 h, and the measurement value of transcutaneous bilirubin at 72 h had a high correlation with serum bilirubin. When transcutaneous bilirubin value is higher than 18, the incidence of hyperbilirubinemia should be considered.ConclusionsThe increase of cord blood bilirubin effectively predict the occurrence of neonatal hyperbilirubinemia. There is a good correlation between levels of transcutaneous bilirubin and serum bilirubin. Moreover, combined detection of transcutaneous bilirubin and cord blood bilirubin can significantly improve the prediction accuracy of hyperbilirubinemia. 相似文献
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《Current biology : CB》2020,30(20):4033-4046.e8
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A. Vuillemin D. Ariztegui G. Nobbe C. J. Schubert the Pasado Science Team 《Geomicrobiology journal》2014,31(4):285-298
Methanogenic populations were investigated in subsaline Laguna Potrok Aike sediments, southern Argentina. Microbial density and activity were assessed via cell count and in situ ATP detection for the last ~11K years. Methanogen phylogenetics highlighted species stratification throughout depth, whereas CO2 reduction was the major pathway leading to methane production. Organic substrates, characterized using pore water analysis, bulk organic fractions and saturated fatty acids, showed a clear link between sediment colonization and initial organic sources. Concentrations and δ13C compositions of methane and fatty acids provided final evidence of a microbial imprint on Holocene organic proxies in the most colonized intervals. 相似文献
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Indicators of landscape condition should be selected based on their sensitivity to environmental changes and their capacity to provide early warning detection of those changes. We assessed the performance of a suite of spatial-pattern metrics selected to quantify the condition of the ridge-slough landscape in the Everglades (South Florida, USA). Spatial pattern metrics (n = 14) that describe landscape composition, geometry and hydrologic connectivity were enumerated from vegetation maps of twenty-five 2 × 2 km primary sampling units (PSUs) that span a gradient of hydrologic and ecological condition across the greater Everglades ecosystem. Metrics were assessed in comparison with field measurements from each PSU of landscape condition obtained from regional surveys of soil elevation, which have previously been shown to capture dramatic differences between conserved and degraded locations. Elevation-based measures of landscape condition included soil elevation bi-modality (BISE), a binary measure of landscape condition, and also the standard deviation of soil elevation (SDSE), a continuous measure of condition. Metric performance was assessed based on the strength (sensitivity) and shape (leading vs. lagging) of the relationship between spatial pattern metrics and these elevation-based measures. We observed significant logistic regression slopes with BISE for only 4 metrics (slough width, ridge density, directional connectivity index – DCI, and least flow cost – LFC). More significant relationships (n = 8 metrics) were observed with SDSE, with the strongest associations for slough density, mean ridge width, and the average length of straight flow, as well as for a suite of hydrologic connectivity metrics (DCI, LFC and landscape discharge competence – LDC). Leading vs. lagging performance, inferred from the curvature of the association obtained from the exponent of fitted power functions, suggest that only DCI was a leading metric of the loss of soil elevation variation; most metrics were indeterminate, though some were clearly lagging. Our findings support the contention that soil elevation changes from altered peat accretion dynamics precede changes in landscape pattern, and offer insights that will enable efficient monitoring of the ridge-slough landscape as part of the ongoing Everglades restoration effort. 相似文献
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Five popular but iron-inefficient cultivars were crossed with three efficient genotypes and both parents and F1s were evaluated for iron-efficiency in potted calcareous and noncalcareous soil. The iron-efficient genotypes were dark green or green in both noncalcareous and calcareous soils whereas inefficient types were light green to yellow in calcareous soil. The chlorophyll and active iron (Fe2+) concentration of leaves was less in iron-efficient genotypes compared to efficient types in calcareous soil and reduction of both the parameters from noncalcareous to calcareous soil was considerably high in iron-inefficient lines. There was significant correlation between visual scores, chlorophyll and active iron content. There were no differences among F1s for iron chlorosis and they were all iron-inefficient. The frequency of iron-inefficient plants was higher than the efficient plants in all F2 populations. But most of the productive plants came from iron-efficient segregants indicating strong association between iron-efficiency and productivity. Based on the results selection for iron-efficiency in early generations and extensive evaluation for productivity in advanced generations is suggested for developing varieties for cultivation in calcareous soils. 相似文献
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C. K. Thoeringer U. J. Pfeiffer G. Rammes F. A. Pamplona S. Moosmang C. T. Wotjak 《Genes, Brain & Behavior》2010,9(8):947-957
Environmental factors may unleash genetically determined susceptibility to psychopathology. Great effort has been spent in identifying both the genetic basis and environmental sources of exaggerated fear in animal models of anxiety disorders. Here, we show that the origin of inbred mice, probably via subtle differences in breeding and rearing conditions, may have large consequences specifically on acquisition and retention of fear memories, while leaving anxiety‐related behaviours unaffected. These effects could be seen in BALB/cAnN (BALB), but not in C57BL/6N (C57BL/6) mice, thus suggesting their dependency on the genetic background. Increased susceptibility for developing exaggerated fear responses was accompanied by decreased long‐term depression and increased surface trafficking of the AMPA receptor GluR1 subunit at the level of the basolateral amygdala complex. Together, these data raise a novel caveat in the debate about the origins of variation in behavioural studies with experimental animals. Considering that there are currently no animal models which explicitly consider conceptual analogy to the specific gene–environment interactions observed in the aetiology of phobias, our study might suggest a novel approach and direction for further preclinical studies focusing on such aspects of phobic‐like fears. 相似文献
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Amanda L. Prince Ryan M. Pace Tyler Dean Diana Takahashi Paul Kievit Jacob E. Friedman Kjersti M. Aagaard 《American journal of primatology》2019,81(10-11)
Previously we have shown that the Japanese macaque gut microbiome differs not by obesity per se, but rather in association with high‐fat diet (HFD) feeding. This held true for both pregnant dams, as well as their 1‐year‐old offspring, even when weaned onto a control diet. Here we aimed to examine the stability of the gut microbiome over time and in response to maternal and postweaning HFD feeding from 6 months of age, and at 1 and 3 years of age. In both cross‐sectional and longitudinal specimens, we performed analysis of the V4 hypervariable region of the 16S rRNA gene on anus swabs collected from pregnant dams and their juveniles at age 6 months to 3 years (n = 55). Extracted microbial DNA was subjected to 16S‐amplicon‐based metagenomic sequencing on the Illumina MiSeq platform. We initially identified 272 unique bacterial genera, and multidimensional scaling revealed samples to cluster by age and diet exposures. Dirichlet multinomial mixture modeling of microbiota abundances enabled identification of two predominant enterotypes to which samples sorted, characterized primarily by Treponema abundance, or lack thereof. Approximating the time of initial weaning (6 months), the Japanese macaque offspring microbiome underwent a significant state type transition which stabilized from 1 to 3 years of age. However, we also found the low abundance Treponema enterotype to be strongly associated with HFD exposure, be it during gestation/lactation or in the postweaning interval. Examination of taxonomic co‐occurrences revealed samples within the low Treponema cluster were relatively permissive (allowing for increased interactions between microbiota) whereas samples within the high Treponema cluster were relatively exclusionary (suggesting decreased interactions amongst microbiota). Taken together, these findings suggest that Treponemes are keystone species in the developing gut microbiome of the gut, and susceptible to HFD feeding in their relative abundance. 相似文献
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A male northern elephant seal (Mirounga angustirostris) that was conceived in captivity was stillborn February 14, 1981, at Mystic Marinelife Aquarium in Mystic, Connecticut. Either of two males in the exhibit could have sired the pup. Both were only 3 yr at the time of conception. 相似文献
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