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51.
Inhibitory motor control in children with attention-deficit/hyperactivity disorder: event-related potentials in the stop-signal paradigm. 总被引:4,自引:0,他引:4
Aneta Dimoska Stuart J Johnstone Robert J Barry Adam R Clarke 《Neuropsychopharmacology》2003,54(12):1345-1354
BACKGROUND: The aim of the study was to investigate the inhibitory control of an ongoing motor response and to identify underlying neural deficiencies, manifested in event-related potentials, that cause poorer inhibitory performance in children with attention-deficit/hyperactivity disorder. METHODS: A stop-signal paradigm with a primary visual task and auditory stop signal was used to compare performance in 13 children with attention-deficit/hyperactivity disorder and 13 control children, while event-related potentials were recorded simultaneously. RESULTS: Children with attention-deficit/hyperactivity disorder showed poorer inhibitory performance through a slower inhibitory process. Inhibitory processing of auditory stop signals was marked by a frontal N2 component that was reduced in the attention-deficit/hyperactivity disorder group relative to controls. A central positive component (P3) was associated with the success of inhibiting a response, but there were no group differences in its amplitude or latency. CONCLUSIONS: Findings support the hypothesis of deficient inhibitory control in children with attention-deficit/hyperactivity disorder. Slower inhibitory processing appears to be due to a specific neural deficiency that manifests in the processing of the stop signal as attenuated negativity in the N2 latency range. 相似文献
52.
Intensive versus standard blood glucose awareness training (BGAT) with insulin-dependent diabetes: mechanisms and ancillary effects 总被引:1,自引:0,他引:1
D J Cox L Gonder-Frederick D Julian P Cryer J H Lee F E Richards W Clarke 《Psychosomatic medicine》1991,53(4):453-462
Insulin-dependent diabetes mellitus (IDDM) patients make critical daily self-care decisions on the basis of what they estimate their blood glucose (BG) levels to be. This study: a) replicated efficacy of Standard Blood Glucose Awareness Training (BGAT), b) evaluated the relative efficacy of an Intensive Blood Glucose Awareness Training (BGAT) to enhance patient accuracy of BG estimation, and c) evaluated the mechanisms and ancillary effects of BGAT. Thirty-nine subjects were randomly assigned to one of three groups. Compared with Control, both Standard and Intensive BGAT improved accuracy (p less than 0.001). Intensive BGAT post-treatment accuracy relative to Standard BGAT did not reach statistical significance (p = 0.177). Greater improvement in accuracy was associated with poorer pretreatment accuracy. Only Intensive BGAT improved metabolic control (glycosylated hemoglobin), and this improvement was associated with poorer pretreatment control. The effects of BGAT were highly specific, affecting only accuracy and metabolic control, and not affecting fear of hypoglycemia, diabetes knowledge, of frequency of blood glucose monitoring. 相似文献
53.
Robert J Barry Adam R Clarke Rory McCarthy Mark Selikowitz 《Clinical neurophysiology》2006,117(2):243-251
OBJECTIVE: This study investigated intrahemispheric and interhemispheric EEG coherences as a function of age in girls with different DSM-IV subtypes of Attention-Deficit/Hyperactivity Disorder (AD/HD). It completes a series of 3 studies aimed at clarifying developmental and gender impacts on the coupling between brain regions in this disorder. METHODS: Three groups of 40 children (AD/HD combined type, AD/HD inattentive type, and normal controls) participated. Each group contained 8 females in each of 5, 1-year age bands from 8 to 12 years. EEG was recorded from 21 sites during an eyes-closed resting condition. Wave-shape coherence was calculated for 8 intrahemispheric electrode pairs (4 in each hemisphere), and 8 interhemispheric electrode pairs, within each of the delta, theta, alpha and beta bands. RESULTS: Developmental effects in intrahemispheric coherences at shorter and longer inter-electrode distances were not as predicted by Thatcher's two-compartment model, contrary to previous findings in boys. Females with AD/HD showed evidence of developmental delay and widespread anomalous elevations in coherence. Girls with AD/HD of the combined type showed similar but greater anomalies than girls with AD/HD of the inattentive type. CONCLUSIONS: Girls with AD/HD show coherence anomalies relative to age- and gender-matched controls, which differ substantially from those shown by boys with AD/HD. These coherence anomalies did not differ in nature between girls with different DSM-IV subtypes of AD/HD, suggesting that subtype differences in girls reflect only symptom severity. SIGNIFICANCE: The data reported here indicate qualitative differences in EEG coherences in girls with AD/HD compared with controls, and quantitative differences between girls with different subtypes of AD/HD. Both sets of effects differ in nature from those previously found in boys with AD/HD, showing the need to carefully consider gender in future studies of AD/HD. 相似文献
54.
55.
L P Clarke S J Cullom R Shaw C Reece B C Penney M A King M Silbiger 《Journal of nuclear medicine》1992,33(1):161-166
Quantitative imaging of bremsstrahlung from pure beta emitters is proposed as a means for in vivo management of antibody therapy. The method involves the use of high-energy collimation, an empirically selected broad photon energy window to enhance detector sensitivity, and a Wiener restoration filter to compensate for system blur. The measured and filtered data were obtained for an idealized scattering medium and isolated spherical sources. An effective linear attenuation coefficient of about 0.13 cm-1 was determined from the raw image data of 32P. A coefficient of 0.14 cm-1 was determined after the images were restored using the Wiener filter. The measured attenuation was not significantly dependent on the size of the region of interest or the size of the source. Its variation was within the experimental error of measurement (+/- 5%). The measured sensitivity (6 x 10(-6) cps/Bq) was sufficient for imaging therapy doses of 32P or 90Y. 相似文献
56.
James F. Jekel David F. Allen Nelson Clarke Henry Podlewski Hannah Gray Carolyn Roberts 《The American journal on addictions / American Academy of Psychiatrists in Alcoholism and Addictions》1994,3(1):14-24
Nine years after the beginning of the epidemic of freebase (crack) cocaine abuse in the Bahamas, this historical study was done to characterize the natural course of the epidemic and to estimate the effectiveness of control measures. The authors' data include the incidence of new cases at the only psychiatric hospital in the Bahamas and at the primary community psychiatric clinic in the nation. The Bahamian response included 1) demand reduction, 2) supply reduction, and 3) reduction of money laundering. The annual number of new cases of crack abuse presenting for treatment declined from 1987 to mid-1991 in both facilities, but in 1992 it began rising again in the inpatient setting only. The changes in recent years have been accompanied by an increase in violent crimes against persons, especially robberies. (American Journal on Addictions 1994; 3:14–24) 相似文献
57.
58.
Suzanne C. Tough David W. Johnston Jodi E. Siever Gayleen Jorgenson Linda Slocombe Carolyn Lane Margaret Clarke 《分娩》2006,33(3):183-194
ABSTRACT: Background: The addition of supplementary prenatal support may improve the health and well‐being of high‐risk women and families. The objective of this randomized controlled trial was to examine the impact of supplementary prenatal care on resource use among a community‐based population of pregnant women. Methods: Pregnant women from three urban maternity clinics were randomized (a) to current standard of physician care, (b) to current standard of care plus consultation with a nurse, or (c) to (b) plus consultation with a home visitor. Participants were 1,352 women who received 3 telephone interviews. The primary outcome was resource use (e.g., attended prenatal classes, used nutritional counseling). Results: Overall, those in the nurse intervention group were more likely to attend an “Early Bird” prenatal class and parenting classes, and to use nutrition counseling and agencies that assist with child care. Women provided with extra nursing and home visitation supports were more likely to use a written resource guide, nutrition counseling, and agencies that assist with child care. Among women at higher risk (e.g., language barriers, young maternal age, low income), the nurse intervention significantly increased use of early prenatal classes, whereas the nurse and home visitor intervention significantly increased use of the written resource guide and nutrition counseling. The intervention substantially increased the amount of information received on numerous pregnancy‐related topics but had little impact on resource use for mental health and poverty‐related needs. Among those with added support, resource use among low‐risk women was generally greater than among high‐risk women. Conclusions: Additional support provided by nurses, or nurses and home visitors, can successfully address informational needs and increase the likelihood that women will use existing community‐based resources. This finding was true even for high‐risk women, although this intervention did not reduce the difference in resource use between high‐ and low‐risk women. (BIRTH 33:3 September 2006) 相似文献
59.
Alex W Wilson Stephen J Medhurst Claire I Dixon Nick C Bontoft Lisa A Winyard Kim T Brackenborough Jorge De Alba Christopher J Clarke Martin J Gunthorpe Gareth A Hicks Chas Bountra Daniel S McQueen Iain P Chessell 《European Journal of Pain》2006,10(6):537-549
Clinically, inflammatory pain is far more persistent than that typically modelled pre-clinically, with the majority of animal models focussing on short-term effects of the inflammatory pain response. The large attrition rate of compounds in the clinic which show pre-clinical efficacy suggests the need for novel models of, or approaches to, chronic inflammatory pain if novel mechanisms are to make it to the market. A model in which a more chronic inflammatory hypersensitivity phenotype is profiled may allow for a more clinically predictive tool. The aims of these studies were to characterise and validate a chronic model of inflammatory pain. We have shown that injection of a large volume of adjuvant to the intra-articular space of the rat knee results in a prolonged inflammatory pain response, compared to the response in an acute adjuvant model. Additionally, this model also results in a hypersensitive state in the presence and absence of inflammation. A range of clinically effective analgesics demonstrate activity in this chronic model, including morphine (3mg/kg, t.i.d.), dexamethasone (1mg/kg, b.i.d.), ibuprofen (30mg/kg, t.i.d.), etoricoxib (5mg/kg, b.i.d.) and rofecoxib (0.3-10mg/kg, b.i.d.). A further aim was to exemplify the utility of this chronic model over the more acute intra-plantar adjuvant model using two novel therapeutic approaches; NR2B selective NMDA receptor antagonism and iNOS inhibition. Our data shows that different effects were observed with these therapies when comparing the acute model with the model of chronic inflammatory joint pain. These data suggest that the chronic model may be more relevant to identifying mechanisms for the treatment of chronic inflammatory pain states in the clinic. 相似文献
60.
Nir Giladi Babak Boroojerdi Amos D Korczyn David J Burn Carl E Clarke Anthony H V Schapira 《Movement disorders》2007,22(16):2398-2404
Rotigotine is a new, non-ergot dopamine agonist formulated in a transdermal delivery system. The present study was to investigate the efficacy and safety of the rotigotine transdermal patch in the treatment of early Parkinson's disease. Patients (n = 561) were randomized to rotigotine, ropinirole, or placebo. The titration period was up to 13 weeks, and there was a minimum dose-maintenance period of 24 weeks for ropinirole and 33 weeks for rotigotine. The primary endpoint was the proportion of patients with a minimum of 20% decrease in the combined Unified Parkinson's Disease Rating Scale Part II and Part III scores. The responder rate in the rotigotine group was significantly higher than in the placebo group (52% vs. 30%, P < 0.0001). Transdermal rotigotine at doses < or =8 mg/24 h did not show noninferiority to ropinirole at doses < or =24 mg/day. In a post-hoc subgroup analysis, rotigotine < or =8 mg/24 hours had a similar efficacy to ropinirole at doses < or =12 mg/day. The rotigotine transdermal patch was well tolerated. The most common adverse events were application-site reactions, nausea, and somnolence. Application-site reactions were predominantly mild or moderate in intensity. In conclusion, the rotigotine transdermal patch represents an effective and safe option for the treatment of patients with early Parkinson's disease. 相似文献