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11.
NIELS CHRISTIAN CHRISTENSEN 《Acta paediatrica (Oslo, Norway : 1992)》1977,66(1):43-48
Abstract Concentrations of triglycerides, free fatty acids (FFA) and glycerol were measured in umbilical venous blood from 99 infants with a birth weight of between 1100–2700 g and a gestational age of 27–41 weeks. Thirty infants were small for gestational age (SGA), 58 were appropriate (AGA) and 11 were of uncertain gestational age. In AGA infants with a gestational age of ≥35 weeks, FFA values were lower than in those with a gestational age of>35 weeks; otherwise concentrations of triglycerides, FFA and glycerol were independent of birth weight and gestational age in AGA infants. In SGA infants, higher FFA values were found compared with both AGA and term infants of normal birth weight. Triglyceride values were higher in SGA than in AGA infants. In SGA infants, a significant positive correlation was found between gestational age and concentrations of both FFA and triglycerides. No differences in FFA, glycerol and triglyceride concentrations were seen between asphyxiated and non-asphyxiated AGA infants. 相似文献
12.
SVEND STENVANG PEDERSEN TIM JENSEN NIELS HØIBY CHRISTIAN KOCH ERHARD W. FLENSBORG 《Acta paediatrica (Oslo, Norway : 1992)》1987,76(6):955-961
ABSTRACT. The annual mortality rate of cystic fibrosis patients with chronic Pseudomonas aeruginosa lung infection at the Danish CF-centre ranged from 10 to 20% in the years 1970–1975. In this period the patients received antipseudomonal chemotherapy only during acute exacerbations of infection. From 1976 99 patients acquired chronic P. aeruginosa infection and were given regular and intensive antipseudomonal treatment 3–4 times per year. The patients were followed for 612 patient-years; 7 died and the 10-year survival rate after onset of P. aeruginosa infection was 90%±4%. The annual mortality rate is now 1–2%. Although precipitating antibodies against P. aeruginosa increased significantly, pulmonary function did not deteriorate with duration of infection. Cross-infection between patients caused an increased incidence of chronic P. aeruginosa infection which was reduced by hygienic measures. 相似文献
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Multiparametric Analysis of Heart Rate Variability Used for Risk Stratification Among Survivors of Acute Myocardial Infarction 总被引:5,自引:0,他引:5
ANDREAS VOSS KATERINA HNATKOVA NIELS WESSEL JUERGEN KURTHS RE SANDER ALEXANDER SCHIRDEWAN A JOHN CAMM MAREK MALIK 《Pacing and clinical electrophysiology : PACE》1998,21(1):186-196
A multiparametric heart rate variability analysis was performed to prove if combined heart rate variability (HRV) measures of different domains improve the result of risk stratification in patients after myocardial infarction. In this study, standard time domain, frequency domain and non-linear dynamics measures of HRV assessment were applied to 572 survivors of acute myocardial infarction. Three parameter sets each consisting of 4 parameters were applied and compared with the standard measurement of global heart rate variability HRVi. Discriminant analysis technique and t-test were performed to separate the high risk groups from the survivors. The predictive value of this approach was evaluated with receiver operator (ROC) and positive predictive accuracy (PPA) curves. Results - The discriminant analysis shows a separation of patients suffered by all cause mortality in 80% (best single parameter 74%) and sudden arrhythmic death in 86% (73%). All parameters of set I show a high significant difference (p<0.001) between survivors and non-survivors based on two-tailed t-test. The specificity level of the multivariate parameter sets is at the 70% sensitivity level (ROC) about 85–90%, whereas HRVi shows maximum levels of 70%. The PPA in the all cause mortality group is at the 70% sensitivity level twice as high as the univarihate HRV measure and increases to more than fourfold as high within the VT/VF group. In conclusion, in this population, the multiparametric approach with the combination of four parameters from all domains especially from NLD seems to be a better predictor of high arrhythmia risk than the standard measurement of global heart rate variability. 相似文献
15.
JAN KYST MADSEN STIG HAUNS
E STEFFEN HELQUIST EVA HOMMEL INGER MALTHE NIELS THORSGAARD PEDERSEN HENRIK SENGEL
V DORTE R
NNOW-JESSEN STEEN TELMER HANS-HENRIK PARVING 《Journal of internal medicine》1986,220(4):329-332
ABSTRACT The prevalence of hyperglycaemia and undiagnosed diabetes mellitus was assessed in 214 consecutive patients admitted to the coronary care units with acute myocardial infarction (AMI). On admission, 16 patients (7.5%) had known diabetes, and 19 patients, not previously known to be diabetic, had blood glucose concentrations of ≥9 mmol/1. Fifteen patients survived for 2 months at which time a 75 g oral glucose tolerance test showed diabetes in 9 (60%) and impaired glucose tolerance in 4 (27%). Ten of these 13 patients (77%) with abnormal glucose tolerance had elevated glycosylated haemoglobin (HbA1c) on admission, indicating pre-existing glucose intolerance or diabetes. The prevalence of undiagnosed diabetes was 4.5% (9/198). However, we may have overlooked undiagnosed diabetes in a small number of patients on admission, since only a random blood glucose <8 mmol/1 rules out diabetes, WHO criteria. Elevated blood glucose in patients with AMI is more likely to reflect a stationary pre-existing abnormal glucose tolerance than a temporary stress-induced phenomenon. 相似文献
16.
Neurophysiological correlates of mental arithmetic 总被引:5,自引:0,他引:5
PAUL PAULI WERNER LUTZENBERGER NIELS BIRBAUMER TIMOTHY C. RICKARD LYLE E. BOURNE JR. 《Psychophysiology》1996,33(5):522-529
Thirteen subjects were extensively trained on nine multiplication problems varying in difficulty. Practice was associated with a reaction time speed up and an attenuation of the problem size effect. The introduction of previously unpracticed problems led to a performance rebound to pretraining levels, indicating practice specificity. The event-related potentials were characterized by a late positive complex, followed by a positive slow wave. Offset latency of positive slow wave and preresponse amplitude at parietal electrodes showed practice specificity effects that systematically changed with practice and problem size, indicating an association with the load imposed on working memory. The peak of the late positive complex probably reflects task learning or adaptation effects because it was attenuated by practice predominantly at frontal electrodes, showed no practice specificity, and was not affected by problem size. 相似文献
17.
Assessment of liver function: Principles and practice 总被引:1,自引:0,他引:1
NIELS TYGSTRUP 《Journal of gastroenterology and hepatology》1990,5(4):468-482
18.
JØRGEN FISCHER HANSEN BIRGER HESSE NIELS JUEL CHRISTENSEN 《European journal of clinical investigation》1978,8(1):31-36
To study the mechanisms by which acute beta-adrenergic blockade may change the activity of the sympathetic nervous system we have measured haemodynamic responses including splanchnic blood flow in twenty-three patients with ischaemic heart disease at rest and during supine exercise before and after i.v. injection of 0.039 mmol (10 mg) dl-propranolol. After propranolol both at rest and on exercise blood pressure, cardiac output and heart rate decreased, while splanchnic vascular resistance increased; mixed venous oxygen saturation decreased whilst arterial oxygen saturation and oxygen uptake were unchanged. Plasma noradrenaline increased after propranolol, values correlating with mixed venous oxygen saturation and splanchnic vascular resistance, both at rest and during exercise before and after propranolol, only at rest was there any correlation with arterial blood pressure. The increase in sympathetic nervous activity after propranolol may be due to a reduction in cardiac output and thereby alteration of the metabolic state (oxygen or related factors) in tissues. Afferent neural signals from the tissues may play a significant role in the regulation of sympathetic nervous activity. 相似文献
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20.
Cortical correlates of semantic classical conditioning 总被引:1,自引:0,他引:1
PEDRO MONTOYA WOLFGANG LARBIG FRIEDEMANN PULVERMÜLLER HERTA FLOR NIELS BIRBAUMER 《Psychophysiology》1996,33(6):644-649
Event-related potentials to visually displayed pseudowords were registered from 13 individuals. In a differential conditioning paradigm, half of the pseudowords had previously been paired with a painful electric shock (shock words) and the other half had been presented without shock (nonshock words). Participants were asked to decide if the words had been presented during the conditioning phase or not. Larger N100 amplitudes and a more negativegoing slow wave 400–800 ms after word presentation were found for shock as compared with nonshock words. This effect was stronger over the left than over the right hemisphere. This left-lateralized negativity might reflect the activation of a cell assembly representing the memory of the learned word-shock contingency. Furthermore, the increased N100 amplitude elicited by shock as compared with nonshock words may be interpreted as an increased attentive facilitation for aversive pain-related information as a consequence of conditioning. 相似文献