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11.
A stratified sample of normal infants born at term at Johannesburg Hospital, who attended the hospital for a routine 6-week follow-up visit, were selected to include 43 infants who were exclusively breast-fed, 42 fed a low-sodium formula and 39 fed a high-sodium formula (greater than 10 mmol sodium/l). Dynamic skinfold thickness measurements (DSTM), designed to assess the amount of interstitial fluid, were performed on each infant by the application of a skinfold caliper for a 3-second sampling period at two sites. The curves generated by these applications were recorded and analysed by microcomputer. There were no differences between any of the feeding groups for DSTM measurements of blood pressure suggesting that the range of sodium ingested by these groups of infants had no significant effects on extracellular water content. However, using multiple linear regression, both DSTM and blood pressure were best predicted by body weight and not by age or any other anthropometric measurement. Thus the normal postnatal decrease in extracellular fluid volume and increase in blood pressure appears to be most closely related to an increase in body weight.  相似文献   
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S P Caudill  S J Smith  G R Cooper 《Statistics in medicine》1989,8(3):295-309; discussion 331-2
Using data from the National Health and Nutrition Examination Survey (NHANES II) 1976-1980, we demonstrate how cross-sectional total serum cholesterol surveillance data can be used by an individual to assess current and future personal cholesterol risk status. We propose statistical models, based on a person's current measured cholesterol level and the relationship between cross-sectional age and cholesterol percentile estimates, that will allow prediction of future cholesterol levels or the age at which specified cholesterol risk levels will be reached if no cholesterol-altering intervention is taken. These models incorporate the observed variation in the NHANES II data and expected intraperson biological variation and intralaboratory analytical variation. We illustrate the adequacy of the models using data from the longitudinal Framingham Study.  相似文献   
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Troponin T levels have been monitored in baboons (n = 8) undergoing pig heterotopic heart transplantation, and correlated with a decrease in graft contractions and graft survival. Pig heart graft survival was from 12 to 139 days (mean 45, median 33), and graft failure was associated with predominant thrombotic microangiopathy and ischemia, with focal hemorrhage, and edema. An increase in troponin T levels 5 to 6 days before graft failure correlated closely with diminished graft contractions. An increase in troponin T was a reliable indicator that graft dysfunction was occurring.  相似文献   
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Complications associated with the use of the GlideScope® videolaryngoscope   总被引:1,自引:0,他引:1  
PURPOSE: Two cases are presented wherein the GlideScope videolaryngoscope (GVL) facilitated laryngeal exposure and successful endotracheal intubation, but resulted in pharyngeal injury. CLINICAL FEATURES: GlideScope videolaryngoscopy was performed in two female patients, whose airways were anticipated to present difficulties for direct laryngoscopy. In the first case, following induction of anesthesia, moderate difficulty was encountered in directing the endotracheal tube (ETT) into the patient's larynx. In the second case, minimal difficulty with the GVL was experienced, and no problems were identified with airway instrumentation until the drapes covering the patient's face were removed. In both instances, the ETT had passed through the right palatopharyngeal arch, requiring suturing in the first patient, and electrocautery in the second patient. CONCLUSION: There have been no previously published reports of injuries related to GlideScope laryngoscopy, but perforation of the palatopharyngeal arch occurring in two patients demonstrates a rare but potentially important complication of the GVL. Strategies to minimize this complication are considered.  相似文献   
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Repeated measures designs are often used to evaluate the effectiveness of interventions. In these designs, the outcomes are measured on several occasions before and after implementation of the intervention. Two statistical methods, the repeated measures analysis of variance (RM-ANOVA) and hierarchical linear models (HLM), can be used to analyze the data. The authors provide an overview of the statistical models underlying RM-ANOVA and HLM and discuss the strengths and limitations of each. They propose that the 2 methods are complementary in determining the effectiveness of interventions.  相似文献   
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The purpose of this study was to determine the relationship between selected anthropometric and physiological variables and 10K time. Eleven male wheelchair athletes with spinal cord injuries in training for national competition performed continuous progressive exercise tests on a wheelchair ergometer to determine maximal metabolic and cardiorespiratory values. Anthropometric data were also collected. The laboratory data were analyzed for correlation with the best 10K time of each subject during the test period. The subjects averaged 27 min 30 sec for their 10K races, 2.49 L.min-1 for VO2max and 35 percent for maximal gross mechanical efficiency during submaximal exercise. Speed at peak oxygen consumption (r = -0.66), gross mechanical efficiency (r = -0.56), and body density (r = -0.57) was found to be significantly (p less than 0.10) correlated with 10K time. The results show very little correlation between VO2max and 10K time (r = 0.02). Further study is indicated for the relationship between gross mechanical efficiency, speed at maximal oxygen consumption, body density, and 10K time; these variables may be useful in evaluating training programs for improving race performance.  相似文献   
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The murine BP-3 antigen was initially described as a variably glycosylated cell surface protein of Mr 38,000 to 48,000 on lymphoid and myeloid cells. In the present experiments we found that this antigen is released from the surface of pre-B cells and macrophages by treatment with phosphatidylinositol-specific phospholipase C (PI-PLC), suggesting a glycosyl-phosphatidylinositol (GPI) linkage with the plasma membrane. When the tissue distribution of the BP-3-reactive cells was examined by immunohistology, high levels of the antigen were observed on brush borders of the intestinal epithelial cells, within collecting tubules of the kidney and on a subpopulation of reticular cells located on lymph nodes. Peyer's patches and the white pulp areas of the spleen. In contrast, reticular cells located in the thymus, bone marrow and splenic red pulp did not express the BP-3 antigen. Ontogenic studies revealed that BP-3 was expressed by the reticular cells in peripheral lymphoid tissues in the neonatal period near the time of lymphocyte immigration into these organs. BP-3+ reticular cells were observed in the collapsed periarterial lymphatic sheaths of adult mice depleted of T and B cells by cyclophosphamide treatment and in mice with severe combined immunodeficiency (scid), indicating that development of this reticular network is lymphocyte independent. The BP-3 antigen on the splenic reticular cells was also GPI anchored but its glycosylation pattern differed from that of the BP-3 molecules on pre-B cells. A specific subpopulation of reticular cells is thus marked by the BP-3 antigen, and the distribution and biochemical properties of the molecule make it an attractive candidate for a role in lymphocyte-stromal interactions in the peripheral lymphoid tissues.  相似文献   
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