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Six hundred fourth-graders rated how much they liked to play with each of their classmates and then nominated their three best friends; 296 of the 600 children were assigned sociometric classifications of popular, neglected, average, controversial, or rejected status (the remaining 304 children failed to meet inclusion criteria). Five years later, 267 of the 296 classified children (90.2%) were evaluated on measures of academic performance, social behavior, and psychological adjustment. The number and type of contacts with the juvenile justice system were also determined. In general, children classified as rejected or controversial tended to fare more poorly on indices of long-term adjustment than did children classified as popular, neglected, or average. Results are discussed in terms of the predictive validity of sociometric rating and nomination procedures and their utility in identifying children at risk for later maladjustment.  相似文献   
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Northern Ireland has one of the lowest breastfeeding initiation rates in the world. Given that attitudes toward infant feeding are formed at an early age and a high rate of teenage pregnancy, it has become necessary to survey attitudes to infant feeding and breastfeeding promotion preferences in teenagers in Northern Ireland. Questionnaires were distributed to teenagers aged 14 to 18 years (n = 419) based in 7 schools selected by type and location throughout Northern Ireland. Attitudes to breastfeeding in public reflected preferred infant-feeding method and were positively influenced by prior exposure to breastfeeding (P = .024). Females were more positive than males both in relation to breastfeeding in public (P = .002) and breastfeeding promotion (P = .003). Recommendations for breastfeeding promotion include specific targeting of young people (both male and female) and enabling contact between teenagers and nursing mothers as much as possible.  相似文献   
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The preventive effect of the aldose reductase inhibitor (ARI) ponalrestat on heart-rate variability and the development of autonomic neuropathy in the vagus nerve was investigated in the spontaneously diabetic BB rat. ARI treatment completely prevented the characteristic decrease in heart-rate variability and axonal atrophy of the vagus nerve for 4 mo in hyperglycemic BB rats. After 6 mo of treatment, the preventive effect on heart-rate variability was partial, and the vagus nerve demonstrated an increase in regenerating myelinated and unmyelinated fibers. These data suggest that autonomic neuropathy involving the vagus nerve is metabolically induced by demonstrating that inhibition of the polyol pathway significantly delays the occurrence of functional and structural autonomic neuropathy despite the presence of hyperglycemia.  相似文献   
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A surface receptor complex of M r˜65 000 (p65) and ˜95 000 (p95) is expressed in cells of the central nervous system of mice. This receptor is recognized by monoclonal antibody 87.92.6 or by reovirus type 3 haemagglutinin as unnatural ligands. The p65/p95 receptor is expressed mostly in neural embryonic precursors undergoing proliferation, especially those in the S-G2 phase of the cell cycle. Receptor expression decreases progressively throughout embryogenesis to low but detectable levels in the adult brain. Biochemical characterization revealed that the neural p65/p95 receptor complex is indistinguishable from the p65/p95 receptor expressed in T cells, where receptor ligation leads to a mitogenic block. In neural and lymphoid tissues the p65/p95 receptor (or an associated protein) possesses a tyrosine kinase enzymatic activity. Receptor ligation in neural cells resulted in the rapid tyrosine phosphorylation of cellular proteins which are different from substrates phosphorylated in T cells. Differential substrate coupling to the receptor may account for differences in signal transduction and biology between neural cells and T cells. Further study of this receptor complex may help define important features of neural proliferation, differentiation and survival.  相似文献   
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Summary The fractional clearance of lithium (CLLi/CLcr) calculated in 15 normal healthy adults from a single morning urine aliquot collection, together with a single venous blood sample (FQ) was compared with the average CLLI/CLCR obtained from three timed consecutive urine collections with mid-point blood sampling (FABC). Lithium had been ingested 15–18 h prior to the collection of these samples. Mean CLLi/CLCR was similar (FQ, 0.186, FABC, 0.177), with a highly significant correlation in each individual of CLLI/CLSR measured by either method (r = 0.97,P 0.0001). Proximal tubular reabsorption of sodium using lithium clearance may be calculated from a single urine and blood sample.  相似文献   
40.
The differences in both the biology of pregnancy and the content of routine care between gravidas with and without diabetes mellitus lead to important differences in the potential utility of both ultrasound examination and maternal serum alpha-fetoprotein (MSAFP) screening. However, both diagnostic methods have become standards of care for these patients, without critical evaluation. This study examines the utility of both ultrasound and MSAFP in diabetic women. Four hundred thirty-two women with diabetes mellitus antedating pregnancy were examined sonographically between 12-23 weeks' gestation. Of these, 393 were also screened with MSAFP determinations. At delivery, 32 of these fetuses were found to have 38 major congenital malformations. All fatal or potentially life-threatening defects had been diagnosed in utero by sonography before 24 weeks' gestation. Ultrasound had a positive predictive value of 90% and a negative predictive value of 97% for identification of major birth defects before 24 weeks' gestation. There were 14 MSAFP values greater than 2.0 multiples of the median, and nine of these patients elected to undergo amniocentesis. Maternal serum alpha-fetoprotein screening had a positive predictive value of 17% and a negative predictive value of 94%. No malformations were detected through MSAFP screening that had not been diagnosed by sonography. No malformations missed sonographically were detected by MSAFP screening, and none of the amniocenteses were helpful diagnostically. We conclude that MSAFP screening is of minimal utility for diagnosing major congenital malformations in a high-risk population examined universally by an experienced sonographer.  相似文献   
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