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排序方式: 共有890条查询结果,搜索用时 15 毫秒
881.
Autism is associated with an inability to identify and distinguish one's own feelings. We assessed this inability using alexithymia and empathy questionnaires, and used fMRI to investigate brain activity while introspecting on emotion. Individuals with high functioning autism/Asperger syndrome (HFA/AS) were compared with matched controls. Participants rated stimuli from the International Affective Picture System twice, once according to the degree of un/pleasantness that the pictures induced, and once according to their color balance. The groups differed significantly on both alexithymia and empathy questionnaires. Alexithymia and lack of empathy were correlated, indicating a link between understanding one's own and others' emotions. For both groups a strong relationship between questionnaire scores and brain activity was found in the anterior insula (AI), when participants were required to assess their feelings to unpleasant pictures. Regardless of self-reported degree of emotional awareness, individuals with HFA/AS differed from controls when required to introspect on their feelings by showing reduced activation in self-reflection/mentalizing regions. Thus, we conclude that difficulties in emotional awareness are related to hypoactivity in AI in both individuals with HFA/AS and controls, and that the particular difficulties in emotional awareness in individuals with HFA/AS are not related to their impairments in self-reflection/mentalizing. 相似文献
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Monika A Pradhan MRCOphth Yvonne Ng FRANZCO Adrienne Strickland PG Cert Health Science Peter M George FRCPA Anthony Raizis PhD Jenny Warrington MSc Andrea L Vincent FRANZCO 《Clinical & experimental ophthalmology》2010,38(3):231-236
Background: Retinoblastoma (MIM +180 200) is a malignant neoplasm affecting embryonal retina, associated with mutations in the RB1 gene. This paper investigates the results of RB1 testing in retinoblastoma management in a tertiary referral centre. Methods: A retrospective audit of genetic testing for retinoblastoma from 2003 to 2008, to determine epidemiology, rate of mutation detection and spectrum was undertaken. Eligible probands were identified from the department database and hospital records examined. DNA extracted from tumour tissue and/or peripheral blood was analysed. All patients and families underwent genetic counselling. Results: Twenty patients, including one family, were identified. Eight had bilateral tumours, of whom seven presented before 2 years of age, whereas 10 of 12 unilateral cases presented after 2 years of age. Ten patients (50%) were European, four Maori (20%), three Pacific (15%), two Asian (10%), and one of mixed ancestry (5%). Genetic analysis achieved mutation detection on all affected alleles of all the patients, with tumour tissue available for testing in 19 cases. Ten (40%) had germline mutations (eight bilateral and two unilateral), including one mosaic. 75% of affected Maori had germline mutations compared with 40% Europeans. A wide range of mutations was detected with one novel mutation identified in a familial case. Conclusion: Advances in gene testing have enabled a high rate of mutation detection, particularly when tumour tissue is genotyped. Genetic analysis is integral to the management of retinoblastoma patients allowing enhanced follow‐up care, avoidance of unnecessary examinations, family screening, counselling and reproductive planning, with early tumour detection in predisposed individuals. 相似文献
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Lipids are transported in the blood in four major classes of lipoproteins. The triacylglycerol-rich lipoproteins are chylomicrons and very-low-density lipoproteins (VLDL) which are produced by the small intestine and liver, respectively. These lipoproteins mainly carry fatty acids to adipose tissue and muscle where the triacylglycerol is hydrolysed by lipoprotein lipase. The resulting particles that remain in the blood are chylomicron remnants and low-density lipoprotein (LDL), respectively. The remnant is taken up by the liver via endocytosis which is mediated by a specific receptor for apolipoprotein E (apoE). LDL, which are rich in cholesterol, can also be taken up by the liver or extrahepatic tissues by a receptor-mediated endocytosis that specifically recognises apoB or apoE. Nascent high-density lipoprotein (HDL) particles are secreted by the liver and intestine and then undergo modification to become HDL3 and then HDL2 as they acquire cholesterol ester. They facilitate the reverse transport of cholesterol back to the liver.Little is known of the hormonal regulation of lipoprotein uptake by the liver. Recently, we have shown that insulin and tri-iodothyronine (T3) increase the specific binding of LDL to cultured hepatocytes whereas dexamethasone (a synthetic glucocorticoid) has the opposite effect. The changes in binding produced by insulin and dexamethasone are paralleled by alterations in the rate of degradation of apoB. These findings may in part explain the hypercholesterolaemia and increased risk of premature atherosclerosis that can be associated with poorly controlled diabetes or hypothyroidism. 相似文献
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DM Patel PG Rhodes MH LeBlanc GR Graves C Glick J Morrison 《Acta paediatrica (Oslo, Norway : 1992)》1999,88(8):874-879
This prospective study was designed to identify the role of postnatal penicillin prophylaxis in the prevention of neonatal group B streptococcus (GBS) infection. We studied 10 998 infants. Of these, 5389 were in the penicillin prophylaxis group (PP) and 5609 infants did not receive penicillin prophylaxis (NPP). Infants were allocated to treatment by month of birth, alternating 3-mo blocks or 2-mo blocks to the two groups after the first block was randomly assigned. The use of PP reduced the incidence of clinical sepsis (1.7% PP versus 2.5% NPP, p < 0.01), GBS infection (0.4% PP versus 0.9% NPP, p < 0.001) and deaths from sepsis (0.1% PP versus 0.3% NPP, p < 0.05). We conclude that the routine use of postnatal penicillin prophylaxis appears to be effective in reducing the incidence of clinical sepsis and death from sepsis in neonates. 相似文献
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Bourgoin SG Houle MG Singh IN Harbour D Gagnon S Morris AJ Brindley DN 《Journal of leukocyte biology》2002,71(4):718-728
Cytohesin-1 and ARNO are guanine nucleotide-exchange factors (GEFs) for ADP-ribosylation factor (Arf). Here, we show that ARNO is expressed in HL-60 cells and established that granulocytic differentiation induced with Me2SO stimulated cytohesin-1 but not ARNO expression. Cytohesin-1 levels in HL-60 granulocytes were similar to those in human neutrophils. Me2SO-differentiated HL-60 cells expressed ARNO and cytohesin-1 isoforms with a diglycine and a triglycine motif in their PH domains, respectively. In vitro, ARNO diglycine and cytohesin-1 triglycine enhanced phospholipase D1 (PLD1) activation by Arf1 with near-maximal effects at 250 nM. These effects were marked particularly at low Mg2+ concentrations. PLD activation was well-correlated with GTP binding to Arf1, and cytohesin-1 was always more potent than ARNO in the PLD- and GTP-binding assays. Increasing Mg2+ concentrations reduced PLD and Arf1 activation by Arf-GEFs. fMetLeuPhe and phorbol 12-myristate 13-acetate stimulated ARNO and cytohesin-1 as well as Arf1 translocation to HL-60 cell membranes. fMetLeuPhe-mediated ARNO recruitment, but not cytohesin-1 and Arf1 translocation, was blocked by phosphatidylinositol 3-kinase inhibitors. The combined results demonstrate that cytohesin-1 triglycine participates in a major phosphatidylinositol 3-kinase-independent pathway linking cell-surface receptors to Arf1 activation and translocation in human granulocytes. 相似文献
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