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991.
992.
Sander MC Werkle-Bergner M Lindenberger U 《Cerebral cortex (New York, N.Y. : 1991)》2011,21(12):2809-2819
Estimates of working memory (WM) capacity increase in children, peak in young adulthood, and decline thereafter. Despite this symmetry, the mechanisms causing capacity increments in childhood may differ from those causing decline in old age. The contralateral delay activity (CDA) of the electroencephalogram, an event-related difference wave with a posterior scalp distribution, has been suggested as a neural marker of WM capacity. Here, we examine 22 children (10-12 years), 12 younger adults (20-25 years), and 22 older adults (70-75 years) in a cued change detection paradigm. Load levels and presentation times were varied within subjects. Behaviorally, we observed the expected life-span peak in younger adults and better performance with longer presentation times. With short presentation times, task load increased CDA amplitude and decreased behavioral performance in younger adults. Both effects were less pronounced in older adults. Children showed a unique pattern: Their behavioral load effects were as strong as those of younger adults, but their CDA was unaffected by load. With long presentation times, task load modulated the CDA in children and older adults but not in younger adults. These findings suggest that age-related differences in CDA reflect changes in the top-down control over WM representations. 相似文献
993.
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995.
Insecticide resistance is one of the major threats to the effectiveness of vector control programs. In order to establish a baseline susceptibility profile of Aedes aegypti in the southwest of Colombia, 10 localities in four Departments (States) were evaluated. Standardized WHO bioassay, CDC bottle bioassay and microplate biochemical assays of non-specific β-esterase (NSE), mixed function oxidases (MFO) and acetylcholinesterase were used. Cross resistance was evaluated with field collected mosquitoes that underwent selection pressure in the laboratory from DDT, propoxur and lambdacyhalothrin during three alternate generations. Mosquitoes with mortality rates below 80% in bioassays were considered resistant. Insecticide resistance varied geographically. Insecticide resistance was observed in 100% of localities in which mosquitoes were exposed to DDT, bendiocarb and temephos using both assays. WHO bioassays showed susceptibility to pyrethroids in all the localities evaluated, however CDC bottle bioassays showed decreases in susceptibility especially with lambdacyhalothrin. All localities showed susceptibility to the organophosphate malathion. Mosquitoes from eight regions with evidence of resistance to any of the insecticide evaluated were also evaluated biochemically. Mosquitoes from five of these regions had increased levels of NSE and two regions had increased levels of MFO. Increase levels of NSE explain partially the low susceptibility to temephos found in all the localities. However, the biochemical mechanisms evaluated do not explain all the resistance observed. Cross resistance was observed between the DDT-selected strain and lambdacyhalothrin, and between the lambdacyhalothrin-selected strain and propoxur and vice versa. The selected strains do not show changes in the biochemical assays evaluated, therefore the observed cross-resistance suggests different biochemical mechanisms. This study shows that Ae. aegypti from Colombia can develop resistance to most of the insecticide classes in the market. Periodic surveillance of insecticide resistance is necessary in order to maintain effective interventions. This study helped to establish the National Network for the surveillance of the insecticide resistance in Colombia. 相似文献
996.
Marianne S Desmedt Yolande L de la Kethulle Myriam I Deveugele Emmanuel A Keirse Dominique J Paulus Johan J Menten Steven R Simoens Paul J vanden Berghe Claire M Beguin 《BMC palliative care》2011,10(1):2
Background
Hospital care plays a major role at the end-of-life. But little is known about the overall size and characteristics of the palliative inpatient population. The aim of our study was to analyse these aspects. 相似文献997.
de Pontual L Kettaneh D Gordon CT Oufadem M Boddaert N Lees M Balu L Lachassinne E Petros A Mollet J Wilson LC Munnich A Brugière L Delattre O Vekemans M Etchevers H Lyonnet S Janoueix-Lerosey I Amiel J 《Human mutation》2011,32(3):272-276
Neuroblastoma (NB) is a frequent embryonal tumor of sympathetic ganglia and adrenals with extremely variable outcome. Recently, somatic amplification and gain-of-function mutations of the anaplastic lymphoma receptor tyrosine kinase (ALK) gene, either somatic or germline, were identified in a significant proportion of NB cases. Here we report a novel syndromic presentation associating congenital NB with severe encephalopathy and abnormal shape of the brainstem on brain MRI in two unrelated sporadic cases harboring de novo, germline, heterozygous ALK gene mutations. Both mutations are gain-of-function mutations that have been reported in NB and NB cell lines. These observations further illustrate the role of oncogenes in both tumour predisposition and normal development, and shed light on the pleiotropic and activity-dependent role of ALK in humans. More generally, missing germline mutations relative to the spectrum of somatic mutations reported for a given oncogene may be a reflection of severe effects during embryonic development, and may prompt mutation screening in patients with extreme phenotypes. 相似文献
998.
Remmelink M de Leval L Decaestecker C Duray A Crompot E Sirtaine N André S Kaltner H Leroy X Gabius HJ Saussez S 《Histopathology》2011,58(4):543-556
Remmelink M, de Leval L, Decaestecker C, Duray A, Crompot E, Sirtaine N, André S, Kaltner H, Leroy X, Gabius H‐J & Saussez S(2011) Histopathology 58, 543–556 Quantitative immunohistochemical fingerprinting of adhesion/growth‐regulatory galectins in salivary gland tumours: divergent profiles with diagnostic potential Aims: This study tests the hypothesis that histopathological fingerprinting of galectins, which are emerging multifunctional effectors in cell sociology, could refine the differential diagnosis of salivary tumours. Methods and results: We applied non‐crossreactive polyclonal antibodies against galectin‐1 (Gal‐1), galectin‐3 (Gal‐3), galectin‐7 (Gal‐7) and galectin‐8 (Gal‐8) for immunohistochemical analysis of salivary gland tumours (72 cases with benign disease and 39 cases with malignancy) and 29 control specimens. The principal positivity of cases, the site of signal presence and the quantitative parameters concerning percentage of positive cells and labelling intensity were determined. Acinic cell and adenoid cystic carcinomas (specifically tubular and cribriform types) shared the expression signature of Gal‐1, Gal‐3 and Gal‐8 presence combined with Gal‐7 absence. Mucoepidermoid carcinomas presented a unique profile based on cytoplasmic Gal‐1, Gal‐3, Gal‐7 and Gal‐8 localization in the intermediate cells. Adenomas were separable from malignancy by a consistent decrease in the labelling index (LI) for Gal‐7 and Gal‐8 (LI Gal‐7, P < 10?6; LI Gal‐8, P = 0.001). When present, staining for the tumour suppressor p16INK4a coincided with Gal‐1 presence. Conclusions: Expression profiling of the four tested galectins in salivary gland tumours revealed non‐uniform staining patterns with discriminatory potential based on intracellular localization and quantitative aspects. 相似文献
999.
Deveugele M Derese A De Bacquer D van den Brink-Muinen A Bensing J De Maeseneer J 《Patient education and counseling》2004,54(3):283-289
This study explores the relation between the diagnosis made by the general practitioner (GP) and his or her communicative behavior within a consultation, by means of the analysis of 2095 videotaped consultations of 168 GPs from six countries participating in the Eurocommunication study. The doctors' diagnoses were coded into ICPC chapters and merged into seven clinically relevant diagnostic clusters. The communicative behavior was gauged by means of the Roter interaction analysis system (RIAS). We found the most important differences for consultations about psychosocial problems as compared to all other diagnostic categories. In these consultations, doctors show more affective behavior, are more concerned about having a good relationship with their patients, ask more questions and give less information than in other consultations. The percentages of utterances in the other diagnostic categories were pretty similar. The communicative behavior of doctors reflects a global pattern in every consultation. This pattern is the most stable for affective behavior (social talk, agreement, rapport building and facilitation). Within instrumental behavior (the other categories), the directions and the information the doctor gives are adapted to the problems presented. 相似文献
1000.
CS Chan JD Peterson TS Gertler KE Glajch RE Quintana Q Cui LE Sebel JL Plotkin W Shen M Heiman N Heintz P Greengard DJ Surmeier 《The Journal of neuroscience》2012,32(27):9124-9132
Mice carrying bacterial artificial chromosome (BAC) transgenes have become important tools for neuroscientists, providing a powerful means of dissecting complex neural circuits in the brain. Recently, it was reported that one popular line of these mice--mice possessing a BAC transgene with a D(2) dopamine receptor (Drd2) promoter construct coupled to an enhanced green fluorescent protein (eGFP) reporter--had abnormal striatal gene expression, physiology, and motor behavior. Unlike most of the work using BAC mice, this interesting study relied upon mice backcrossed on the outbred Swiss Webster (SW) strain that were homozygous for the Drd2-eGFP BAC transgene. The experiments reported here were conducted to determine whether mouse strain or zygosity was a factor in the reported abnormalities. As reported, SW mice were very sensitive to transgene expression. However, in more commonly used inbred strains of mice (C57BL/6, FVB/N) that were hemizygous for the transgene, the Drd2-eGFP BAC transgene did not alter striatal gene expression, physiology, or motor behavior. Thus, the use of inbred strains of mice that are hemizygous for the Drd2 BAC transgene provides a reliable tool for studying basal ganglia function. 相似文献