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81.
The international collaborative study of maternal phenylketonuria: status report 1994 总被引:1,自引:0,他引:1
R Koch HL Levy R Matalon B Rouse WB Hanley F Trefz C Azen EG Friedan F de la Cruz F Güttler PB Acosta 《Acta paediatrica (Oslo, Norway : 1992)》1994,83(S407):111-119
Neonatal screening for phenylketonuria (PKU) has created a problem as females with PKU are reaching child-bearing age. Surveys have revealed that maternal phenylalanine blood concentrations greater than 1200 μmol/l are associated with fetal microcephaly, congenital heart defects and intrauterine growth retardation. It is estimated that as many as 3000 hyperphenylalaninemic females may be at risk of producing these fetal abnormalities. To examine this problem, the international maternal PKU collaborative study was developed to evaluate the efficacy of a phenylalanine-restricted diet in reducing fetal morbidity. Preliminary findings have indicated that phenylalanine restriction should begin before conception for females with PKU planning a pregnancy. Dietary control should maintain maternal blood phenylalanine levels between 120 and 360 μmol/l and should provide adequate energy, protein, vitamin and mineral intake. Pregnant hyperphenylalaninemic females who achieved metabolic control after conception or by the 10th week of pregnancy had a better offspring outcome than anticipated. The results of 402 pregnancies are reviewed. 相似文献
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Kirk A. Frey Robert A. Koeppe Michael R. Kilbourn Thierry M. Vander Borght Roger L. Albin Sid Gilman David E. Kuhl 《Annals of neurology》1996,40(6):873-884
We present development and human application of a method for determining the regional cerebral density of the type 2 vesicular monoamine transporter (VMAT2) using positron emission tomography (PET) and [11C]dihydrotetrabenazine (DTBZ). Previous animal studies indicate striatal VMAT2 density is linearly related to the integrity of substantia nigra dopamine neurons and is not subject to drug-or lesion-compensatory regulation. In the present studies, kinetic compartmental modeling was employed to estimate blood-brain [11C]DTBZ transport (K1,) and VMAT2 binding site density (tissue-to-plasma DTBZ distribution volume, DV)from the cerebral and plasma DTBZ time courses her intravenous tracer injection. In controls, we found reductions of putamen DTBZ DV with advancing age, corresponding to losses of 0.77% per year in specific VMAT2 binding. Parkinson's disease (PD) patients had reduction in specific DTBZ DV in the putamen (?61%) and in the caudate nucleus (?43%). There was no overlap of lowest specific putamen DTBZ DV between individual elderly controls and PD patients. The present results indicate the suitability of [11C]DTBZ PET for objective quantification of nigrostriatal integrity, including evaluation of PD progression and its possible therapeutic modification. 相似文献
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Regional myocardial dysfunction: evaluation of patients with prior myocardial infarction with fast CT 总被引:1,自引:0,他引:1
Lipton MJ; Farmer DW; Killebrew EJ; Bouchard A; Dean PB; Ringertz HG; Higgins CB 《Radiology》1985,157(3):735-740
A prototype ultrafast cine computed tomographic (CT) scanner, designed specifically for cardiac imaging, was used to evaluate a preliminary series of patients with prior myocardial infarction (n = 21) and a control group without coronary artery disease (n = 5). Multilevel 50-msec CT scan exposures were obtained during peripheral intravenous bolus injections of contrast medium. A comparison was made between cine-CT scans and standard left ventriculographic images in assessing segmental left ventricular motion. Results indicate that cine CT, performed at sufficiently rapid speeds (20 scans per second) to allow useful analysis of regional ventricular wall motion, can provide adequate image quality. Analysis of 110 segments revealed a good correlation (90.9%) between the two techniques in characterizing normal from abnormal regional wall motion. Cine CT, based on this initial study, demonstrates considerable potential for evaluating not only cardiac chamber dimensions but also segmental wall dynamics. 相似文献
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Zullig KJ Huebner ES Gilman R Patton JM Murray KA 《American journal of health behavior》2005,29(3):206-214
OBJECTIVE: To investigate the psychometric properties of the BMSLSS among 522 college students. METHODS: Internal consistency reliability explored scale reliability, factor analysis explored construct validity, known-groups validity was assessed by use of items from the National College Youth Risk Behavior Survey and Harvard National Survey of Alcohol Use, and criterion-related validity was explored through analyses with the CDC's Health-Related Quality of Life Scale. RESULTS: Acceptable internal consistency reliability, construct, known-groups, and criterion-related validity were established. CONCLUSIONS: These findings offer preliminary support for the BMSLSS; it could serve as part of comprehensive evaluations of subjective QOL for program evaluation and/or policy purposes among college students. 相似文献
90.
Sir Victor Horsley is well recognized as the father of neurological surgery, publishing many articles within this discipline and on other neurologically related topics. Furthermore, he published many important articles in other areas of science and medicine, as well as on social issues (e.g., women's suffrage). Accordingly, we compiled, for the first time, a complete listing of his writings. We briefly describe here some of the characteristics of his bibliography, which is available on the Journal's web site. 相似文献