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排序方式: 共有353条查询结果,搜索用时 15 毫秒
71.
Jesper Kj?rgaard Lone Graff Stensballe Nina Marie Birk Thomas N?rrelykke Nissen Kim Thestrup Foss Lisbeth Marianne Th?stesen Gitte Thybo Pihl Andreas Andersen Poul-Erik Kofoed Ole Pryds Gorm Greisen 《PloS one》2016,11(4)
ObjectivesTo assess the non-specific effect of Bacillus Calmette-Guérin (BCG) vaccination at birth on psychomotor development.DesignThis is a pre-specified secondary outcome from a randomised, clinical trial.SettingMaternity units and paediatric wards at three university hospitals in Denmark.ParticipantsChildren born at gestational age (GA) 32 weeks and above. All women planning to give birth at the three sites were invited during the recruitment period. Out of 4262 randomised children, 144 were premature (GA < 37 weeks). There were 2129 children (71 premature) randomised to BCG and 2133 randomised (73 premature) to the control group.InterventionsBCG vaccination 0.05 ml was given intradermally in the upper left arm at the hospital within seven days of birth. Children in the control group did not receive any intervention. Parents were not blinded to allocation.ResultsThe mean difference in ASQ score at 12 months adjusted for age and prematurity was -0.7 points (BCG vs. control, 95% confidence interval; -3.7 to 2.4), p = 0.67, corresponding to an effect size of Cohen’s d = -0.015 (-0.082 to 0.052). The mean difference in ASQ score for premature children at 22 months was -7.8 points (-20.6 to 5.0, p = 0.23), d = -0.23 (-0.62 to 0.15).ConclusionsA negative non-specific effect of BCG vaccination at birth on psychomotor development was excluded in term children.
Trial Registration
ClinicalTrials.gov NCT01694108相似文献72.
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74.
Utilization of leaf, stem, root, and latex starch was monitored in Euphorbia esula L. plants. Leaf, stem, and root starch decreased rapidly during a 52 day light starvation period while latex starch did not. Scanning electron and light microscope studies provided additional evidence that no changes in latex starch granules had occurred. Amylase activity (6.6 units per milligram protein) could be isolated from latex. However, latex starch granules were extremely resistant to enzymic hydrolysis by latex amylases, Bacillus subtilis α-amylase, and by amyloglucosidase from Aspergillus niger. Results indicate that latex starch grains do not function as utilizable carbohydrate in this species under these conditions. 相似文献
75.
B T Mortensen N R Hartmann I J Christensen J K Larsen T Kristensen S B Wieslander N I Nissen 《Cell and tissue kinetics》1986,19(3):351-364
Cultures of the promyelocytic cell line HL 60 were synchronized with thymidine. A concentration of 0.05 mM thymidine and an exposure time of 24 hr was found optimal for blocking about 90% of the cells in S phase. Following release from the thymidine block the cell cultures were followed intermittently over 40 hr for fluctuation in cell numbers, labelling with radioactive thymidine and nuclear DNA distributions. Mathematical evaluation of the results revealed a cycling time of 18.6 hr and a duration of specific cell phases of 8.6 hr, 7.1 hr and 2.9 hr for G1, S and G2 + M, respectively. The doubling time was 26 hr and the growth fraction was estimated as 1. 相似文献
76.
Summary A histochemical study of the renal interstitial cells demonstrates the absence of two of the principal enzymes involved in the citric acid cycle, the cells thus seem to lack the ability to break down fatty acids. On the other hand the renal interstitial cells demonstrate enzyme activity which could be indirect evidence of fatty acid synthesis. A pronounced nodular acid phosphatase activity and unspecific esterase activity were noticed as well as an uniform cytoplasmic esterase activity.This work was supported by a grant from the Danish State Research Foundation. 相似文献
77.
Binding of 125I-bovine and chicken insulin to cultured embryonic chick skeletal muscle cells was studied. Bovine and chicken insulin bound cultured cells with high affinities of 2.4 X 10(9)M-1 and 4.8 X 10(9)M-1 and low affinities of 2.4 X 10(7)M-1 and 3.7 X 10(7)M-1, respectively. Maximum insulin binding was achieved after 90 min of incubation at 20 degrees C and the maximum value was maintained for an additional 3 hr. Insulin binding increased in a linear manner with increasing nuclei number over a 5-fold range. Maximum insulin binding per nuclei decreased as cell fusion increased between 24 and 72 hr in culture, primarily due to a decrease in the number of low affinity insulin receptors. 相似文献
78.
Primary explants of Picea abies (L.) Karst. and Pinus sylvestris L. were incubated for various periods in solutions containing different concentrations of [14 C]-benzyladenine. Time course analysis showed that uptake was linear for the initial 60 min; after this time linear uptake continued but at a much reduced rate. The amount of benzyladenine taken up by the explants saturated at a concentration about one third of that of the medium, Concentration dependence experiments showed that BA uptake was directly proportional to the external concentration. These results and those from experiments in which uptake was examined at different temperatures are consistent with a passive mode of BA uptake. The results are discussed with respect to in vitro micropropagation. 相似文献
79.
Lorenzo Nissen Barbara Sgorbati Bruno Biavati Georgios N. Belibasakis 《Annals of microbiology》2014,64(2):611-617
Beneficial microbes, such as lactobacilli establish a symbiosis with the host and confer health-associated effects, by limiting the growth of indigenous pathogens and challenging microbes introduced by altered foods. Nevertheless, there is scarce information on the effects of beneficial microbes on the virulence properties of bacterial species associated with oral diseases, such as periodontitis. Aggregatibacter actinomycetemcomitans is a Gram-negative species highly implicated in the etiology of localized aggressive periodontitis. The objective of this study was to investigate the effect of lactobacilli on the expression of the two major virulence factors of A. actinomycetemcomitans. Lactobacillus salivarius and L. gasseri were selected as beneficial species. The gene expressions of leukotoxin (LtxA) and cytolethal distending toxin (CdtB) by A. actinomycetemcomitans were analyzed in response to challenge by lactobacilli cell-free supernatants. Neither lactobacilli affected the growth, but strongly attenuated the expressions of both CdtB and LtxA in the two A. actinomycetemcomitans strains tested. This reduction of the expression of these two exotoxins was time-dependent. These fundamental findings may indicate that lactobacilli can reduce the virulence of putative opportunistic oral pathogens, and may provide insights to future therapeutic approaches for the respective diseases. 相似文献
80.
N H Heegaard J W Sen N C Kaarsholm M H Nissen 《The Journal of biological chemistry》2001,276(35):32657-32662
Aggregation and fibrillation of beta(2)-microglobulin are hallmarks of dialysis-related amyloidosis. We characterize perturbations of the native conformation of beta(2)-microglobulin that may precede fibril formation. For a beta(2)-microglobulin variant cleaved at lysine 58, we show using capillary electrophoresis that two conformers spontaneously exist in aqueous buffers at neutral pH. Upon treatment of wild-type beta(2)-microglobulin with acetonitrile or trifluoroethanol, two conformations were also observed. These conformations were in equilibrium dependent on the sample temperature and the percentage of organic solvent present. Circular dichroism showed a loss of beta-structures and gain of alpha-helices. Reversal to the native conformation occurred when removing the organics. Affinity capillary electrophoresis experiments showed increased specific interactions of the nonnative beta(2)-microglobulin conformation with the dyes 8-anilino-1-naphthalene sulfonic acid and Congo red. The observations may relate to early folding events prior to amyloid fibrillation and facilitate the development of methods to detect and inhibit pro-amyloid protein and peptide conformations. 相似文献