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31.
Loranger Michel; Pépin Michel; Gignac Guy; Benoit Geneviève 《Canadian Metallurgical Quarterly》1995,36(1):59
Presents results of 3 studies on the psychometric properties of the LP-ABC (M. Loranger and M. Pépin, 1993), a French-language instrument for assessing general functioning in adults with mental retardation. The studies involved a total of 299 male and female Canadian adults with mental retardation. Results confirm the internal consistency, construct validity, criterion validity, discriminant validity, interrater reliability, and test–retest reliability of the LP-ABC. (English abstract) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
32.
TG Orsière MM Chauvet MH Dell''Amico MJ Bourdeaux 《Canadian Metallurgical Quarterly》1995,291(3):237-243
Hepatocyte growth factor (HGF) is a potent mitogen for the maturation of hepatocytes in vitro which plays a role in liver regeneration in vivo. In addition, transforming growth factor-beta 1 (TGF-beta 1) is also a potent regulator of liver regeneration. In attempting to clarify the mechanisms related to liver regeneration after partial hepatectomy, we investigated the expression of HGF and TGF-beta 1 in rats with liver cirrhosis (LC). A rat model of LC was prepared using carbon tetrachloride (CCl4). The expression of HGF mRNA in both the LC and control groups showed a similar time-course with the highest expression seen at 18h after a 70% hepatectomy. The expression of TGF-beta 1 mRNA peaked at 18h after partial hepatectomy in the LC group and at 48h in the control group. The 5-bromo-2'-deoxyuridine (BrdU) labeling index for the LC group at 24, 48, and 72 h after partial hepatectomy was 9.2%, 5.9%, and 1.8%, while for the control group it was 7.0%, 11.7%, and 6.8%, respectively. The BrdU labeling index in the LC group was thus suppressed earlier than that in the control group. We therefore postulate that regeneration of the remnant liver in the presence of LC accelerates immediately after partial hepatectomy, but the extent of regeneration is insufficient because of an early cessation due to an early expression of TGF-beta 1. 相似文献
33.
Antnio Ravara Ana G. Matos Vasco T. Vasconcelos Luís. Lopes 《Electronic Notes in Theoretical Computer Science》2003,85(1):61-79
We define a lexically scoped, asynchronous and distributed π-calculus, with local communication and process migration. This calculus adopts the network-awareness principle for distributed programming and follows a simple model of distribution for mobile calculi: a lexical scope discipline combines static scoping with dynamic linking, associating channels to a fixed site throughout computation. This discipline provides for both remote invocation and process migration. A simple type system is a straightforward extension of that of the π-calculus, adapted to take into account the lexical scope of channels. An equivalence law captures the essence of this model: a process behavior depends on the channels it uses, not on where it runs. 相似文献
34.
Wistar rats, eight days old, were subjected to permanent bilateral forebrain ischemia, followed by hypoxia for 15 minutes. A cerebral infarct, mainly involving the cerebral neocortex, hippocampus, amygdala, striatum and subcortical white matter was produced. Neurons and glia showing punctate chromatin condensation and karyorrhectic cells were observed 12 hours after hypoxia-ischemia. Their number increased during the first two days and recruitment of cells with degenerating nuclei occurred until day five. In situ labeling of nuclear DNA fragmentation stained many normal-appearing nuclei, as well as punctate chromatin condensations and nuclear fragments in karyorrhectic cells. Delayed neuronal death in the CA1 area of the hippocampus was observed after 20 minutes of transient forebrain ischemia in the adult gerbil. In situ labeling of nuclear DNA fragmentation demonstrated stained punctate chromatin condensation in a few degenerating cells at 48 hours post-ischemia. Substantial labeling of CA1 neurons occurred in the fourth day. Agarose gel electrophoresis of extracted brain DNA from ischemic infant rats and adult gerbils showed a ladder-type pattern which is typical of nuclear DNA fragmentation into oligonucleosomal fragments (internucleosomal cleavage). These findings suggest that endonuclease(s) activation may play a role in cell death induced by different forms of hypoxia-ischemia. 相似文献
35.
INTRODUCTION AND DEVELOPMENT: Multiple sclerosis (ME) is an inflammatory disease of the myelin of the central nervous system, the origin of which is still unknown. Genetic, infectious, immunological and environmental factors have all been blamed, but none of these factors on their own can explain the whole spectrum of this disease. Of the environmental factors, fat in the diet has given rise to most discussion. At the present time, it is known that polyunsaturated essential fatty acids form a part of biological membranes. A relationship has been found between the dietary fat consumed and the plasma levels and cell membrane content. CONCLUSIONS: The possible immuno-modulation function of these fatty acids justify rigorous evaluation of this hypothesis. 相似文献
36.
F Gaymard G Pilot B Lacombe D Bouchez D Bruneau J Boucherez N Michaux-Ferrière JB Thibaud H Sentenac 《Canadian Metallurgical Quarterly》1998,94(5):647-655
SKOR, a K+ channel identified in Arabidopsis, displays the typical hydrophobic core of the Shaker channel superfamily, a cyclic nucleotide-binding domain, and an ankyrin domain. Expression in Xenopus oocytes identified SKOR as the first member of the Shaker family in plants to be endowed with outwardly rectifying properties. SKOR expression is localized in root stelar tissues. A knockout mutant shows both lower shoot K+ content and lower xylem sap K+ concentration, indicating that SKOR is involved in K+ release into the xylem sap toward the shoots. SKOR expression is strongly inhibited by the stress phytohormone abscisic acid, supporting the hypothesis that control of K+ translocation toward the shoots is part of the plant response to water stress. 相似文献
37.
38.
B Amy de la Bretèque 《Canadian Metallurgical Quarterly》1995,116(4):271-272
The adolescent's breaking of the voice is the result of the substitution of the chest voice (or heavy mechanism) for the head voice (or light mechanism). In cases of late breaking, the voice is abnormally high-pitched and feeble, often with a distorted timbre, while the larynx is normal and pubescent. Such people are generally not fully aware of their voices' real nature. Therapy classically resorts to laryngeal manipulations, of which a new technique is put forward. Another therapeutic approach is based, on the one hand, on critical listening compared with a control male voice, thus enabling the subject to become aware of his own voice, and, on the other hand, on high intensity work which helps passing from head to chest voice. 相似文献
39.
G Pons-Lladó F Carreras X Borrás J Palmer J Llauger A Bayés de Luna 《Canadian Metallurgical Quarterly》1997,79(12):1651-1656
To compare the value of echocardiography and magnetic resonance imaging (MRI) in the assessment of the amount and extent of hypertrophy in hypertrophic cardiomyopathy (HC) and, second, to correlate the degree of hypertrophy, as assessed by MRI, with clinical and electrocardiographic parameters, 30 consecutive patients (16 men and 14 women, aged 20 to 74 years) with HC were studied. Measurements of left ventricular wall thickness were performed at 11 predetermined segments (5 basal, 5 midventricular, and 1 apical) by 2-dimensional echocardiography and MRI. Two parameters derived from MRI studies were considered as indicators of the degree and extent of hypertrophy: (1) mean of the measured wall thickness at the 11 segments, and (2) the number of segments with thickness > 15 mm. Results showed that, from a total of 330 myocardial segments, thickness could be measured by echocardiography in 221 (67%), whereas MRI allowed measurement of 320 segments (97%). When compared with clinical and electrocardiographic data, no correlation was found regarding mean wall thickness and number of hypertrophied segments by MRI except for the presence of an abnormal electrocardiographic repolarization pattern. It is concluded that MRI allows a better assessment of the degree and extension of left ventricular hypertrophy than echocardiography in HC. Despite the precise information on hypertrophy provided by MRI, the amount and degree of hypertrophy bears no correlation with most of the clinical data in these patients. 相似文献
40.
S Merino A Aguilar JM Tomás R Bonet MJ Martinez D Simón-Pujol F Congregado 《Canadian Metallurgical Quarterly》1997,22(5):315-320
1. We investigated the effect of exercise on plasma adrenomedullin, atrial natriuretic peptide (ANP) and brain natriuretic peptide (BNP) concentrations and studied the relationship between these peptides and haemodynamic parameters in nine patients with old myocardial infarction (MI) and in eight normal subjects. 2. The exercise protocol consisted of two fixed work loads (40 and 80 W) for 4 min each and venous blood samples were taken at rest, during each exercise stage and after exercise while monitoring the mean arterial pressure (MAP) and heart rate (HR). In MI, pulmonary arterial pressure (PAP), pulmonary capillary wedge pressure (PCWP), left ventricular end-diastolic pressure (LVEDP) and cardiac output (CO) were measured throughout exercise. 3. Adrenomedullin levels did not significantly increase with exercise. Adrenomedullin levels correlated with PAP and PCWP at rest (P < 0.05). Atrial natriuretic peptide levels correlated with PAP, PCWP and LVEDP throughout exercise (P < 0.05) but, on multiple regression analysis, PCWP correlated only with ANP (P < 0.01). Brain natriuretic peptide levels correlated with LVEDP throughout exercise (P < 0.01) and its increment correlated closely with basal BNP levels at rest (P < 0.01). 4. These results suggest that adrenomedullin does not respond to the acute haemodynamic changes of exercise, whereas ANP responds to it and PCWP is the major stimulus factor. Brain natriuretic peptide responds to exercise in proportion to the basal synthesis of BNP in patients with left ventricular dysfunction and LVEDP may play a role in increasing BNP during exercise. 相似文献