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21.
An extensive evaluation was conducted with 16-yr-old monozygotic twins concordant for the fragile X full mutation but discordant for mental retardation. The clearly affected twin had an IQ score of 47; 77% of her neuropsychological z scores were at least 2 SDs below average. Her sister had an IQ score of 105 and average neuropsychological performance. However, each girl demonstrated relative verbal strengths and visual-spatial weaknesses. Their parents rated each girl as having significant problems with attention, conduct, anxiety-withdrawal, and hyperactivity. The girls did not rate themselves as having significant anxiety. These findings are consistent with group data on females with fragile X and demonstrate the wide range of effects associated with the fragile X full mutation. This case report implicates the importance of a psychosocial phenotype of fragile X independent of cognitive ability level. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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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   
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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   
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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   
25.
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   
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The authors investigated the relationship between plasma lipids and the risk for cortical infarction (61 cases) and transient ischaemic attacks (TIA) (35 cases) compared with matched controls. They observed a maximal increase of total cholesterol, of very low-density lipoprotein and low-density lipoprotein (LDL), triglycerides, total apolipoprotein (Apo), B,LDL-Apo B and Apo-A1, and small size high-density lipoprotein (HDL) and large size HDL whose separation was not possible. In contrast they observed a decrease of HDL-ApoE, a distribution of LDL in a single fraction and the presence of LDL of low weight in the group with cortical infarction with or without cardiac arrhythmias. For the first time, we describe a decrease of the HDL-ApoE/total ApoE ratio. TIA differed from the former group by a low level of HDL and the lack of abnormalities of Apo-A1, distribution of small and large size HDL, and in the distribution and the weight of LDL. These data suggest that previously demonstrated differences in LDL-cholesterol and HDL-cholesterol levels between patients with ischaemic stroke and control subjects may apply to patients with cortical infarction, and that in TIA there are changes in the distribution and the weight of LDL.  相似文献   
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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   
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