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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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RMP-7, a nine-amino acid bradykinin analogue, has been shown in animals to temporarily increase the permeability of the blood brain barrier to small molecules including amphotericin B, when administered intravenously. We sought to evaluate the safety of escalating doses of RMP-7 administered to human volunteers with the acquired immune deficiency syndrome (AIDS). Six HIV antibody-positive adults with CD4+ cell counts <50/mm3 received three increasing doses of RMP-7 on successive days: 30 ng/kg, 100 ng/kg and 300 ng/kg infused over 2, 2 and 10 min, respectively. Adverse experiences were dose-related, mild-moderate in intensity, primarily related to vasodilation and resolved rapidly without sequelae. Mean maximum increases in pulse rate at 30 ng/kg, 100 ng/kg and 300 ng/kg were 4.0, 7.8 and 28.2 beats per min, respectively. The maximum changes in average mean arterial pressure were +7.7, +5.6 and −0.2 mmHg from baseline, respectively. Minor increases in liver enzymes were noted in three patients, all with pre-existing enzyme elevations. Despite the high frequency of both occult and overt cardiovascular abnormalities in advanced HIV infection, RMP-7 is shown to be safe in this group of AIDS patients at all dosage levels tested, with adverse effects similar to previous experience in healthy humans.  相似文献   
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Impact of education for physicians on patient outcomes   总被引:4,自引:0,他引:4  
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Hyperlactatemia is a documented complication of diabetic ketoacidosis (DKA). Lactate responses during DKA treatment have not been studied and were the focus of this investigation. Blood gas and electrolyte data from 25 DKA admissions to ICU were sequenced over 24 h from the first Emergency Department sample. Hyperlactatemia (>?2 mmol/L) was present in 22 of 25 DKA presentations [mean concentration?=?3.2 mmol/L]. In 18 time-series (72%), all concentrations normalized in?≤?2.6 h (aggregate decay t1/2?=?2.29 h). In the remaining 7 (28%), hyperlactatemia persisted?>?12 h. These were females (P?=?0.04) with relative anemia (hemoglobin concentrations 131 v 155 g/L; P?=?0.004) and lower nadir glucose concentrations (5.2 v 8.0 mmol/L, P?=?0.003). Their aggregate glucose decay curve commenced higher (42 mmol/L v 29 mmol/L), descending towards a lower asymptote (8 mmol/L v 11 mmol/L). Tonicity decay showed similar disparities. There was equivalent resolution of metabolic acidosis and similar lengths of stay in both groups. Hyperlactatemia is common in DKA. Resolution is often rapid, but high lactates can persist. Females with high glucose concentrations corrected aggressively are more at risk. Limiting initial hyperglycemia correction to?≥?11 mmol/L may benefit.

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Background: Prior research has shown that cerebral asymmetry is associated with differences in corpus callosum connectivity. Such associations were detected in histological and anatomical studies investigating callosal fiber size and density, in neuroimaging investigations based on structural and diffusion tensor imaging, as well as in neuropsychological experiments. However, little is known about typical associations between these factors, and even less about the relative influences of magnitude and direction of cerebral asymmetries. Here, we investigated relationships between callosal connectivity and cerebral asymmetry using precise measures of callosal thickness and selected cerebral structures. We considered both the direction and magnitude of the asymmetries. Methods: Associations between cerebral asymmetry and callosal thickness were investigated in 348 cognitively healthy older individuals. Results: The magnitude and direction of cerebral lateralization were significant independent predictors of callosal thickness. However, associations were small. Leftward asymmetry and increased magnitude of asymmetry were generally associated with increased callosal thickness, mostly in the callosal midbody and isthmus. Conclusions: When a large sample of normal individuals is considered, cerebral asymmetries are only subtly associated with callosal thickness. Hum Brain Mapp, 2013. © 2012 Wiley Periodicals, Inc.  相似文献   
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Thein  SL; Hesketh  C; Brown  JM; Anstey  AV; Weatherall  DJ 《Blood》1989,73(4):924-930
Two families, one of Anglo-Saxon-Dutch descent, and the other, West Indian black, have an atypical beta thalassemia characterized by an unusually high level of Hb A2 in the heterozygous state. Restriction endonuclease mapping showed a deletion of about 1.35 kilobase (kb) in the 5' region of the beta globin gene. Direct sequencing of a specific region of genomic DNA amplified by a new modification of the polymerase chain reaction defined the deletion to be 1,393 base pairs (bp) and to be the same in both families. The deletion extends from 485 bp 5' to the mRNA CAP site to the middle of the second intervening sequence. This deletion, together with three others previously described that remove the 5' end of the beta gene but leave the delta gene intact, are all associated with unusually high levels of Hb A2 in the heterozygous state.  相似文献   
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