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To investigate whether the secular trend for growth in Dutch children still exists, the Oosterwolde I study of 1980 was repeated in 1989. A persisting secular trend was visible for height while the z scores of body proportions show no change during the past 10 years, which suggests that there is no change in the timing of puberty. 相似文献
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A retrospective review of post-delivery antibody records was performed at a teaching hospital and a community hospital to determine the frequency of new red cell alloantibody production and transfusion during pregnancy. If alloantibody was undetected at delivery, it was assumed that alloimmunization had not occurred. When antibody was detected, a chart review was performed to determine if the antibody was present at the beginning of the pregnancy or was newly produced during the pregnancy. A total of 17,568 pregnancies were reviewed. Antibody was detected at delivery in 948 (5.4%) cases, of which 89.5 percent (848/948) involved passive anti-D or clinically insignificant antibodies. The remaining 100 pregnancies involved clinically significant IgG antibodies. In 58 pregnancies, the antibody was detected in the first trimester, and in 42, new antibody production occurred during the pregnancy. Thus, the prevalence of new antibody production during pregnancy was 0.24 percent (95% confidence interval [CI], 0.17-0.32). Transfusion records indicated that the prevalence of transfusions during pregnancy was 0.09 percent (95% CI, 0.04-0.14). None of the women with new alloantibody formation during their pregnancies required transfusion; hence, new alloantibody production and the need for transfusion appear to be independent events. The probability of these events occurring together was 2.1 × 10(-6), or 1 in 500,000 deliveries. 相似文献
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Bartels MN Jelic S Ngai P Gates G Newandee D Reisman SS Basner RC De Meersman RE 《Respiratory physiology & neurobiology》2004,144(1):91-98
Heart rate variability (HRV) and systolic blood pressure variability (BPV) during incremental exercise at 50, 75, and 100% of previously determined ventilatory threshold (VT) were compared to that of resting controlled breathing (CB) in 12 healthy subjects. CB was matched with exercise-associated respiratory rate, tidal volume, and end-tidal CO(2) for all stages of exercise. Power in the low frequency (LF, 0.04-0.15 Hz) and high frequency (HF, >0.15-0.4 Hz) for HRV and BPV were calculated, using time-frequency domain analysis, from beat-to-beat ECG and non-invasive radial artery blood pressure, respectively. During CB absolute and normalized power in the LF and HF of HRV and BPV were not significantly changed from baseline to maximal breathing. Conversely, during exercise HRV, LF and HF power significantly decreased from baseline to 100% VT while BPV, LF and HF power significantly increased for the same period. These findings suggest that the increases in ventilation associated with incremental exercise do not significantly affect spectral analysis of cardiovascular autonomic modulation in healthy subjects. 相似文献
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The expression and regulation of class II antigens in normal and inflammatory bowel disease peripheral blood monocytes and intestinal epithelium 总被引:2,自引:0,他引:2
Elevated constitutive expression of major histocompatibility (MHC) class II antigens occurs in the enterocytes of patients with IBD. It has been suggested that this aberrant expression of class II molecules may play a role in the pathogenesis of IBD. We examined two possible reasons for such a finding. 1) Heightened sensitivity of IBD enterocytes to endogenous gamma interferon (gamma IFN) and 2) enhanced endogenous secretion of gamma interferon by intestinal cells in close proximity to the enterocytes (lamina propria lymphocytes). Constitutive and gamma interferon stimulated HLA-DR and DP density on intestinal epithelial cells (IEC) and peripheral blood monocytes (PBM) from UC patients (IEC n = 13; PBM n = 20), CD patients (IEC n = 14; PBM n = 18) and non-IBD controls (IEC n = 12; PBM n = 20) were measured via flow cytometry (mean channel fluorescence). gamma IFN production by PHA stimulated and unstimulated lamina propria lymphocyte (LPL) cultures of UC patients (n = 11) CD patients (n = 8) and non-IBD controls (n = 11) was measured using a vesicular stomatitis virus/WISH cell bioassay. We found significantly greater gamma IFN secretion by IBD-derived PHA stimulated LPL than from non-IBD stimulated controls (CD = 39.4 +/- 12.4u; UC41.5 +/- 6.8u; NL = 22.4 +/- 8.3u, p less than 0.05) while gamma IFN induced HLA-DR and DP upregulation was no greater in IBD-derived IEC and PBM than in non-IBD controls.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
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Frequent administration by inhalation of salbutamol and ipratropium bromide in the initial management of severe acute asthma in children 总被引:1,自引:0,他引:1
J Reisman M Galdes-Sebalt F Kazim G Canny H Levison 《The Journal of allergy and clinical immunology》1988,81(1):16-20
A study was performed to compare the efficacy and safety of two therapeutic regimens for the treatment of children presenting to the emergency department with acute asthma. A regimen of inhaled salbutamol alone was compared to inhaled salbutamol combined with ipratropium bromide. Twenty-five children ranging in age from 5 to 15 years were enrolled in the study. Children with FEV1 less than or equal to 55% predicted were eligible to participate in the study. Subjects were randomized in a double-blind fashion into one of two treatment groups. Both groups received an initial dose of salbutamol by nebulizer of 150 micrograms/kg (0.03 cc/kg), followed by six consecutive doses of 50 micrograms/kg (0.01 cc/kg) at 20-minute intervals. In one group of subjects, 250 micrograms (1.0 ml) of ipratropium bromide respirator solution was added to the salbutamol administered at the time of the initial inhalation, and at 40 and 80 minutes, whereas the remaining subjects received a placebo with salbutamol at those times. Formal one-way statistical ANOVA with change in percent predicted FEV1 as a response variable confirmed there was a statistically significant difference at all time points caused by drug regimen during the 150-minute observation period. There was no significant difference in side effects reported in the two groups. Significant additional bronchodilation achieved with salbutamol and ipratropium bromide together indicates that there is likely a substantial cholinergic element to the bronchospasm observed in acute exacerbations of asthma in the pediatric age group. 相似文献
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