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81.
A‐M Widström G Lilja P Aaltomaa‐Michalias A Dahllöf M Lintula E Nissen 《Acta paediatrica (Oslo, Norway : 1992)》2011,100(1):79-85
Aim: The aim of this study was to provide a more detailed analysis of the infant’s behavioural sequence that begins immediately after birth and terminates with grasping the nipple, suckling and then falling asleep. Method: Twenty‐eight full‐term infants were videotaped immediately after birth. A video protocol was developed to examine infant behaviours identified from five random videotapes. Results: When birth crying had stopped, the babies showed a short period of relaxation and then successively became alert. They went through an ‘awakening phase’, an ‘active phase’ with movements of limbs, rooting activity and looking at the mother’s face, a ‘crawling phase’ with soliciting sounds, a ‘familiarization phase’ with licking of the areola, and a ‘suckling phase’ and last a ‘sleeping phase’. Five factors related to the time spent to locate the breast: more number of looks at the breast 10–20 min after birth (p < 0.0001); and exposure to meperidine (p = 0.0006) related to increased time. Early start of crawling (p = 0,0040); increased number of ‘soliciting sounds’ (p = 0.0022); and performing hand–breast–mouth movements (p = 0.0105) related to shorter time. Conclusion: Inborn breastfeeding reflexes were depressed at birth, possibly because of a depressed sensory system. It is hypothesized that when the infant is given the option to peacefully go through the nine behavioural phases birth cry, relaxation, awakening, activity, crawling, resting, familiarization, suckling and sleeping when skin‐to‐skin with its mother this results in early optimal self‐regulation. 相似文献
82.
Louise Seimyr Berit Sj?gren Barbara Welles-Nystr?m Eva Nissen 《Archives of women's mental health》2009,12(5):269-279
The present study investigates if mothers and fathers have similar ways of thinking and feeling about their babies during
late pregnancy and how aspects of parental–fetal attachment are related to maternal depressive mood. Two hundred and ninety-eight
Swedish-speaking women at 30–32 weeks of gestation and partners (n = 274) participated in the study. Socio-demographic background data were collected. Prenatal attachment was assessed with
the maternal/paternal–fetal attachment scale (MFA/PFA), and depressive symptoms were assessed by the Edinburgh postnatal depression
scale (EPDS). MFA and PFA scores mirrored each other. After factor analysis, five different factors loaded somewhat differently
for men were revealed as significant. These factors were (I) concerns about the fetus and health behavior, (II) mental preparation
to take care of the unborn child, (III) experiences of pregnancy, (IV) experiences of fetal movements, and (V) naming of the
baby. Factors III and IV were related to depressive symptoms. Mothers with slight depressive symptoms were somewhat less positive
about the pregnancy but showed more attention to the fetal movements. Midwives should conduct interviews on the women’s psychosocial
history and use validated instruments, which may help them to identify problems with the psychosocial health of the mother
and her partner as they journey through pregnancy and transition to parenthood. 相似文献
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84.
Unexpected nondenitrifier nitrous oxide reductase gene diversity and abundance in soils 总被引:5,自引:0,他引:5
Robert A. Sanford Darlene D. Wagner Qingzhong Wu Joanne C. Chee-Sanford Sara H. Thomas Claribel Cruz-García Gina Rodríguez Arturo Massol-Deyá Kishore K. Krishnani Kirsti M. Ritalahti Silke Nissen Konstantinos T. Konstantinidis Frank E. L?ffler 《Proceedings of the National Academy of Sciences of the United States of America》2012,109(48):19709-19714
Agricultural and industrial practices more than doubled the intrinsic rate of terrestrial N fixation over the past century with drastic consequences, including increased atmospheric nitrous oxide (N2O) concentrations. N2O is a potent greenhouse gas and contributor to ozone layer destruction, and its release from fixed N is almost entirely controlled by microbial activities. Mitigation of N2O emissions to the atmosphere has been attributed exclusively to denitrifiers possessing NosZ, the enzyme system catalyzing N2O to N2 reduction. We demonstrate that diverse microbial taxa possess divergent nos clusters with genes that are related yet evolutionarily distinct from the typical nos genes of denitirifers. nos clusters with atypical nosZ occur in Bacteria and Archaea that denitrify (44% of genomes), do not possess other denitrification genes (56%), or perform dissimilatory nitrate reduction to ammonium (DNRA; (31%). Experiments with the DNRA soil bacterium Anaeromyxobacter dehalogenans demonstrated that the atypical NosZ is an effective N2O reductase, and PCR-based surveys suggested that atypical nosZ are abundant in terrestrial environments. Bioinformatic analyses revealed that atypical nos clusters possess distinctive regulatory and functional components (e.g., Sec vs. Tat secretion pathway in typical nos), and that previous nosZ-targeted PCR primers do not capture the atypical nosZ diversity. Collectively, our results suggest that nondenitrifying populations with a broad range of metabolisms and habitats are potentially significant contributors to N2O consumption. Apparently, a large, previously unrecognized group of environmental nosZ has not been accounted for, and characterizing their contributions to N2O consumption will advance understanding of the ecological controls on N2O emissions and lead to refined greenhouse gas flux models. 相似文献
85.
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87.
Nutritional supplementation of the leucine metabolite beta-hydroxy-beta-methylbutyrate (hmb) during resistance training 总被引:1,自引:0,他引:1
Panton LB Rathmacher JA Baier S Nissen S 《Nutrition (Burbank, Los Angeles County, Calif.)》2000,16(9):734-739
The effects of supplementation of the leucine metabolite beta-hydroxy-beta-methylbutyrate (HMB) were examined in a resistance training study. Thirty-nine men and 36 women between the ages of 20-40 y were randomized to either a placebo (P) supplemented or HMB supplemented (3.0 g HMB/d) group in two gender cohorts. All subjects trained three times per week for 4 wk. In the HMB group, plasma creatine phosphokinase levels tended to be suppressed compared to the placebo group following the 4 wk of resistance training (HMB:174. 4 +/- 26.8 to 173.5 +/- 17.0 U/L; P:155.0 +/- 20.8 to 195.2 +/- 23.5 U/L). There were no significant differences in strength gains based on prior training status or gender with HMB supplementation. The HMB group had a greater increase in upper body strength than the placebo group (HMB:7.5 +/- 0.6 kg; P:5.2 +/- 0.6 kg; P = 0.008). The HMB groups increased fat-free weight by 1.4 +/- 0.2 kg and decreased percent fat by 1.1% +/- 0.2% while the placebo groups increased fat-free weight by 0.9 +/- 0.2 kg and decreased percent fat by 0.5% +/- 0.2% (fat-free weight P = 0.08, percent fat P = 0.08, HMB compared to placebo). In summary, this is the first short-term study to investigate the roles of gender and training status on the effects of HMB supplementation on strength and body composition. This study showed, regardless of gender or training status, HMB may increase upper body strength and minimize muscle damage when combined with an exercise program. 相似文献
88.
89.
90.
Kaestel CG Jørgensen A Nielsen M Eriksen KW Ødum N Holst Nissen M Röpke C 《Experimental eye research》2002,74(5):627-637
The purpose of this study was to characterize the effects of human retinal pigment epithelial (RPE) cells on activated T cells. Activated T cells were cocultured with adult and foetal human RPE cells whereafter apoptosis and proliferation were determined by flow cytometry and (3)H-Thymidine incorporation assay, respectively. T cells and RPE cells were cultured directly together or in a transwell system for determination of the effect of cell contact. The importance of cell surface molecules was examined by application of a panel of blocking antibodies (CD2, CD18, CD40, CD40L, CD54, CD58) in addition to use of TCR negative T cell lines. The expression of IL2R-alpha -beta and -gamma chains of activated T cells was analysed by flow cytometry after incubation of T cells alone or with RPE cells. Human RPE cells were found to inhibit the proliferation of activated T cells by a cell contact-dependent mechanism. The RPE cells inhibitory abilities were not affected by blocking of any of the tested surface molecules. The inhibition of the T cells' proliferation correlates with a decreased expression of IL2R-beta and -gamma chains. The T cells regain their ability to proliferate and increase their IL2R-beta and -gamma chain expression within 24 hr after removal from the coculture. It is concluded that the cultured human adult and foetal RPE cells inhibit the proliferation of activated T cells by a process that does not involve apoptosis. It depends on cell contact but the involved surface molecules were not revealed. The proliferation inhibition correlates with a modulation of the T cells' expression of IL2R, and is reversible. 相似文献