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排序方式: 共有454条查询结果,搜索用时 15 毫秒
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Kulik W van Weissenbruch MM Menelik N Cranendonk A Kneepkens CM Lafeber HN 《Journal of chromatography. B, Biomedical sciences and applications》2001,750(1):147-153
The [13C]octanoic acid breath test was used for the measurement of differences in gastric emptying in preterm infants for the evaluation of pharmacological therapy. In order to perform a good intra-individual comparison of the gastric emptying in preterm infants under non-standardisable test conditions, we adjusted t1/2 for variations in non-recovered label (=label retention) and introduced an "effective half 13CO2 breath excretion time" t1/2eff = t1/2/m expressed as min per percentage of the cumulative dose recovered. In a pilot study, we investigated the action of the gastrointestinal prokinetic drug cisapride on gastric emptying in seven premature infants, of whom four suffered from gastric stasis and three had constipation. The postnatal age and weight at the start of treatment ranged from 15 to 64 days and from 815 to 1635 g, respectively. All infants received the standard formula for premature infants (Nenatal, Nutricia). Cisapride was administered orally 0.2 mg/kg, four times daily. The changes in gastrointestinal motility were studied using the total bowel transit time of carmine red. After 7 days of treatment in all children, the gastric emptying coefficient and the half 13CO2 breath excretion time adjusted for label retention were improved (n=7, the gastric emptying coefficient range before treatment was 1.69-3.34 (mean 2.59 +/- 0.80) and after treatment it was 2.79-3.76 (mean 3.28 +/- 0.30); the half 13CO2 breath excretion time adjusted for label retention range before treatment was 3.0-14.7 min/% dose (mean 7.0 +/- 5.0) and after treatment 2.6-4.0 min/% dose (mean 3.1 +/- 0.6). The total bowel transit time was only slightly improved in two patients (n=7, mean total bowel transit time before: 23.7 h compared to mean total bowel transit time after 7 days of treatment: 35.5 h). Side effects during cisapride treatment were not seen. We conclude that in premature infants cisapride is effective in shortening gastric emptying time and reducing gastric stasis; the therapeutic role in constipation has to be further investigated. 相似文献
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T. C. Jansen H. N. Lafeber H. K. A. Visser G. Kwant B. Oeseburg W. G. Zijlstra 《Medical & biological engineering & computing》1978,16(3):274-277
A membrane-covered catheter-tip oxygen-electrode system is described, which gives a linear response in the Po2 range of 0–350 mm Hg. The system is highly stable, free from drift and mechanically safe for application in man. This is accomplished by using a screw cap for fastening the membrane holder, thus preventing the loss of parts and making the electrolyte chamber really fluidtight. Insulation of the platinum wire with glass precludes the possibility of fluid-bridge contact with the silver anode beyond the measuring site at the tip. 相似文献
4.
Taams LS Vukmanovic-Stejic M Smith J Dunne PJ Fletcher JM Plunkett FJ Ebeling SB Lombardi G Rustin MH Bijlsma JW Lafeber FP Salmon M Akbar AN 《European journal of immunology》2002,32(6):1621-1630
Anergic/suppressive CD4+CD25+ T cells have been proposed to play an important role in the maintenance of peripheral tolerance. Here we demonstrate that in humans these cells suppress proliferation to self antigens, but also to dietary and foreign antigens. The suppressive CD4+CD25+ T cells display a broad usage of the T cell receptor Vbeta repertoire,suggesting that they recognize a wide variety of antigens. They reside in the primed/memory CD4+CD45RO+CD45RB(low) subset and have short telomeres, indicating that these cells have the phenotype of highly differentiated CD4+ T cells that have experienced repeated episodes of antigen-specific stimulation in vivo. This suggests that anergic/suppressive CD4+CD25+ T cells may be generated in the periphery as a consequence of repeated antigenic encounter. This is supported by the observation that highly differentiated CD4+T cells can be induced to become anergic/suppressive when stimulated by antigen presented by non-professional antigen-presenting cells. We suggest that besides being generated in the thymus, CD4+CD25+ regulatory T cells may also be generated in the periphery. This would provide a mechanism for the generation of regulatory cells that induce tolerance to a wide array of antigens that may not be encountered in the thymus. 相似文献
5.
Predictive value of neonatal MRI as compared to ultrasound in premature infants with mild periventricular white matter changes 总被引:4,自引:0,他引:4
van Wezel-Meijler G van der Knaap MS Oosting J Sie LT de Groot L Huisman J Valk J Lafeber HN 《Neuropediatrics》1999,30(5):231-238
A follow-up study was performed in 42 premature infants in whom serial neonatal ultrasound and a single neonatal MRI of the brain was normal, or showed mild periventricular white matter changes. The aim of the study was to evaluate the clinical significance of periventricular signal intensity changes on MRI and to compare the predictive value of neonatal MRI with that of ultrasound. The infants underwent repeated standardised motor assessments and developmental tests. MRI was repeated at the corrected age of 12 months. Pronounced periventricular signal intensity changes on neonatal MRI and periventricular echodensities (flaring) on ultrasound were associated with a high incidence of transient motor problems during infancy. The degree of echogenicity carried the highest predictive value, as compared to duration of flaring on ultrasound and degree of periventricular signal intensity change on MRI. It is concluded that signal intensity changes on neonatal MRI represent the same ischaemic change of the periventricular white matter as flaring on ultrasound and that routine neonatal MRI screening is not warranted in premature infants without clinical evidence of neurological problems and with normal or mildly abnormal ultrasound scans. Recording of the degree of echogenicity should become a routine procedure in neonatal cerebral ultrasonography. 相似文献
6.
MR patterns of hypoxic-ischemic brain damage after prenatal, perinatal or postnatal asphyxia 总被引:7,自引:0,他引:7
The relationship between MR patterns of brain damage and type or timing of perinatal hypoxia-ischemia was studied. MR images of 104 children with evidence of bilateral posthypoxic-ischemic brain damage and neonatal records were reviewed. Three different MR patterns were found. Periventricular leukomalacia occurred in 73 children, in 82% after a history of subacute or chronic hypoxia-ischemia, in 71% after preterm birth. Predominant lesions of basal ganglia and thalamus occurred in 21 children, in 95% preceded by acute profound asphyxia, in 85% after term birth. Multicystic encephalopathy occurred in 10 infants, in 70% preceded by mild signs of hypoxia-ischemia, followed by an unexpectedly severe encephalopathy, in 60% after term birth. Statistical analysis showed that the patterns of injury were primarily related to the type of hypoxia-ischemia. We conclude that the type of hypoxia-ischemia, rather than the postconceptional age at occurrence determines the pattern of brain injury. 相似文献
7.
Human influenza A (H5N1) cases, urban areas of People's Republic of China, 2005-2006 总被引:1,自引:0,他引:1
Yu H Feng Z Zhang X Xiang N Huai Y Zhou L Li Z Xu C Luo H He J Guan X Yuan Z Li Y Xu L Hong R Liu X Zhou X Yin W Zhang S Shu Y Wang M Wang Y Lee CK Uyeki TM Yang W;Avian Influenza HN study Group 《Emerging infectious diseases》2007,13(7):1061-1064
We investigated potential sources of infection for 6 confirmed influenza A (H5N1) patients who resided in urban areas of People's Republic of China. None had known exposure to sick poultry or poultry that died from illness, but all had visited wet poultry markets before illness. 相似文献
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