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Insulin-like growth factors (IGF-I and -II) are peptide growth factors that may be important for neonatal development. Specific high affinity IGF binding proteins (BPs) have been characterized in serum and extracellular fluids. The major serum binding complex in the adult has an apparent Mr of 150 K, while the predominant BP in the neonate is approximately 30 K. In the rat, the transition from the neonatal BP to the adult form occurs during the third postnatal week, concomitant with an increase in serum IGF-I and a decrease in serum IGF-II concentrations. Using specific RIAs and Western ligand blot analyses we have characterized the changes in serum IGF and IGF BPs, respectively, during the early postnatal period. Seven BPs were identified in serum with apparent Mr values of 42, 41, 40, 38, 28, 26, and 22 K. After deglycosylation, the 42, 41, 40, and 38 K BPs were reduced to two bands with apparent Mr values of 35 and 32 K, while the 28, 26, and 22 K BP were unchanged. In the neonate, the 28, 26, and 22 K BPs were present, with the 28 K BP in highest concentration. With increasing age, the 28 K BP decreased and the 42, 41, 40, and 38 K BPs appeared at approximately 19 days of age. Comparison of Western ligand blots of neonatal serum, BRL-3A conditioned media, rat amniotic fluid, and rat cerebrospinal fluid (CSF) demonstrated that all contained a prominent 28 K BP. A polyclonal antibody (alpha Hec 1) developed against the 31 K human IGF-BP (hBP-31) immunoprecipitated the 28 K BP from neonatal rat serum, BRL-3A media, rat amniotic fluid, and rat CSF, but did not react with adult rat serum. These findings suggest that, in the rat, the predominant neonatal serum BP is structurally and immunologically similar to the major BRL-3A, amniotic fluid, and CSF BPs, but distinct from the predominant adult serum BP. 相似文献
3.
Pyloromyotomy of Ramstedt: experience of a nonspecialized centre 总被引:2,自引:0,他引:2
In a general hospital over a period of 6 years 57 infants with congenital hypertrophic stenosis underwent a Ramstedt pylorotomy. In most cases a surgical resident-in-training performed the operation under the direct supervision of a general surgeon. There were no complications of anesthesia, no deaths and no substantial morbidity. The majority of infants left the hospital within 48 hours. The results in this series compared favourably with those reported from more specialized centres. 相似文献
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R M Rosenfeld 《Archives of otolaryngology--head & neck surgery》1992,118(4):445-447
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Impact of pediatricians' attire on children and parents 总被引:1,自引:0,他引:1
R V Marino W Rosenfeld P Narula M Karakurum 《Journal of developmental and behavioral pediatrics : JDBP》1991,12(2):98-101
To evaluate perceptions of a pediatrician's attire, 50 children and parents in an outpatient facility were shown five photographs of a female or a male physician dressed differently (formal to informal). A list of positive and negative attributes was presented to the parents and children who were to match each picture to the attributes. Parents had a strong positive preference for the formally dressed female (short white coat and skirt), and the formally dressed male (short white coat and tie). More than 50% of the parents least preferred the most informal attire. Children had no clear preferences for males and preferred the female in the blouse and skirt. Children assigned negative attributes to informal attire but not to the same degree as did their parents. This study demonstrates that parents have stronger preferences than do their children. Although children had no strong positive preferences, they may feel negatively about informal attire. 相似文献
7.
PURPOSE: To assess the consistency of ratings assigned by health sciences faculty members relative to community members during an innovative admissions protocol called the Multiple Mini-Interview (MMI). METHOD: A nine-station MMI was created and 54 candidates to an undergraduate MD program participated in the exercise in Spring 2003. Three stations were staffed with a pair of faculty members, three with a pair of community members, and three with one member of each group. Raters completed a four-item evaluation form. All participants completed post-MMI questionnaires. Generalizability Theory was used to examine the consistency of the ratings provided within each of these three subgroups. RESULTS: The overall test reliability was found to be .78 and a Decision Study suggested that admissions committees should distribute their resources by increasing the number of interviews to which candidates are exposed rather than increasing the number of interviewers within each interview. Divergence of ratings was greater within the pairing of community member to faculty member and least for pairings of community members. Participants responded positively to the MMI. CONCLUSION: The MMI provides a reliable protocol for assessing the personal qualities of candidates by accounting for context specificity with a multiple sampling approach. Increasing the heterogeneity of interviewers may increase the heterogeneity of the accepted group of candidates. Further work will determine the extent to which different groups of raters provide equally valid (albeit different) judgments. 相似文献
8.
K L Dawson-Falk A M Wright B Bakker P T Pitlick D M Wilson R G Rosenfeld 《Australasian radiology》1992,36(3):204-209
Forty patients with karyotypically proven Turner syndrome were prospectively studied using magnetic resonance imaging (MRI) and echocardiography in order to determine the frequency of cardiovascular anomalies and to assess the utility of both imaging modalities as methods for cardiovascular evaluation in Turner syndrome. Cardiovascular anomalies were found in 45% of patients. A high absolute prevalence of bicuspid aortic valve (17.5%) and aortic coarctation (12.5%) were observed relative to comparable series. Of clinically significant abnormalities, three of five aortic coarctations and four of five ascending aortic dilatations were solely MRI detected and not evident at echocardiographic examination. MRI is thus seen as a valuable adjunct to echocardiography in the cardiovascular evaluation of Turner syndrome patients. The usefulness of MRI primarily relates to its ability to provide excellent visualisation of the entire thoracic aorta where a large proportion of clinically significant anomalies occur in Turner syndrome. 相似文献
9.
Macrophage colony-stimulating factor mRNA and protein in atherosclerotic lesions of rabbits and humans. 总被引:20,自引:3,他引:17 下载免费PDF全文
M. E. Rosenfeld S. Yl-Herttuala B. A. Lipton V. A. Ord J. L. Witztum D. Steinberg 《The American journal of pathology》1992,140(2):291-300
In this study, the authors demonstrate the expression of mRNA and the presence of protein for macrophage colony-stimulating factor (MCSF) in atherosclerotic lesions from humans and rabbits. In situ hybridization of serial sections of human fatty streaks demonstrated expression of MCSF mRNA by cells dispersed throughout the lesions. Immunocytochemical staining with a panel of MCSF-specific antibodies showed extensive cell-associated staining of all of the cell types in the lesions. Immunocytochemical studies of atherosclerotic lesions from Watanabe heritable hyperlipidemic (WHHL) and cholesterol-fed rabbits demonstrated a similar cell-associated pattern of staining. There was no MCSF-specific staining of aortas from normal rabbits or of cultured aortic smooth muscle cells from either humans or rabbits. Macrophage-derived foam cells (MFC) were isolated from the aortas of ballooned, cholesterol-fed rabbits. A Northern blot demonstrated that RNA isolated from the MFC hybridized with a human cDNA probe for MCSF. RNA from alveolar macrophages isolated simultaneously from the same rabbits did not hybridize with the MCSF probe. Conditioned media from an 18- to 24-hour incubation of the MFC contained colony-stimulating activity as demonstrated in a mouse bone marrow culture assay. Most of this colony-stimulating activity was neutralized by preincubating the conditioned media with an MCSF-specific antibody. 相似文献
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