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排序方式: 共有5361条查询结果,搜索用时 9 毫秒
91.
Luke Nyakarahuka Shannon Whitmer Jackson Kyondo Sophia Mulei Caitlin M. Cossaboom Carson T. Telford Alex Tumusiime Gloria Grace Akurut Dianah Namanya Kilama Kamugisha Jimmy Baluku Julius Lutwama Stephen Balinandi Trevor Shoemaker John D. Klena 《Emerging infectious diseases》2022,28(11):2326
Crimean-Congo hemorrhagic fever (CCHF) was detected in 2 refugees living in a refugee settlement in Kikuube district, Uganda. Investigations revealed a CCHF IgG seroprevalence of 71.3% (37/52) in goats within the refugee settlement. This finding highlights the need for a multisectoral approach to controlling CCHF in humans and animals in Uganda. 相似文献
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Martine Skumlien Claire Mokrysz Tom P. Freeman Matthew B. Wall Michael Bloomfield Rachel Lees Anna Borissova Kat Petrilli James Carson Tiernan Coughlan Shelan Ofori Christelle Langley Barbara J. Sahakian H. Valerie Curran Will Lawn 《Neuropsychopharmacology》2022,47(11):1976
Chronic use of drugs may alter the brain’s reward system, though the extant literature concerning long-term cannabis use and neural correlates of reward processing has shown mixed results. Adolescents may be more vulnerable to the adverse effects of cannabis than adults; however, this has not been investigated for reward processing. As part of the ‘CannTeen’ study, in the largest functional magnetic resonance imaging study of reward processing and cannabis use to date, we investigated reward anticipation and feedback in 125 adult (26–29 years) and adolescent (16–17 years) cannabis users (1–7 days/week cannabis use) and gender- and age-matched controls, using the Monetary Incentive Delay task. Blood-oxygen-level-dependent responses were examined using region of interest (ROI) analyses in the bilateral ventral striatum for reward anticipation and right ventral striatum and left ventromedial prefrontal cortex for feedback, and exploratory whole-brain analyses. Results showed no User-Group or User-Group × Age-Group effects during reward anticipation or feedback in pre-defined ROIs. These null findings were supported by post hoc Bayesian analyses. However, in the whole-brain analysis, cannabis users had greater feedback activity in the prefrontal and inferior parietal cortex compared to controls. In conclusion, cannabis users and controls had similar neural responses during reward anticipation and in hypothesised reward-related regions during reward feedback. The whole-brain analysis revealed tentative evidence of greater fronto-parietal activity in cannabis users during feedback. Adolescents showed no increased vulnerability compared with adults. Overall, reward anticipation and feedback processing appear spared in adolescent and adult cannabis users, but future longitudinal studies are needed to corroborate this.Subject terms: Human behaviour, Cognitive neuroscience, Reward 相似文献
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Patrick D. Worhunsky Gustavo A. Angarita Zu Wei Zhai David Matuskey Jean-Dominique Gallezot Robert T. Malison Richard E. Carson Marc N. Potenza 《Neuropsychopharmacology》2021,46(2):316
Stimulant-use disorders have been associated with lower availability of dopamine type-2 receptors (D2R) and greater availability of type-3 receptors (D3R). Links between D2R levels, cognitive performance, and suppression of the default mode network (DMN) during executive functioning have been observed in healthy and addicted populations; however, there is limited evidence regarding a potential role of elevated D3R in influencing cognitive control processes in groups with and without addictions. Sixteen individuals with cocaine-use disorder (CUD) and 16 healthy comparison (HC) participants completed [11C]-(+)-PHNO PET imaging of D2R and D3R availability and fMRI during a Stroop task of cognitive control. Independent component analysis was performed on fMRI data to assess DMN suppression during Stroop performance. In HC individuals, lower D2R-related binding in the dorsal putamen was associated with improved task performance and greater DMN suppression. By comparison, in individuals with CUD, greater D3R-related binding in the substantia nigra was associated with improved performance and greater DMN suppression. Exploratory moderated-mediation analyses indicated that DMN suppression was associated with Stroop performance indirectly through D2R in HC and D3R in CUD participants, and these indirect effects were different between groups. To our knowledge, this is the first evidence of a dissociative and potentially beneficial role of elevated D3R availability in executive functioning in cocaine-use disorder.Subject terms: Addiction, Cognitive control 相似文献
95.
Johnny L. Carson Laura Zhou Luisa Brighton Katherine H. Mills Haibo Zhou Ilona Jaspers 《Inhalation toxicology》2017,29(3):137-144
Objective: Mucociliary clearance sustains a baseline functionality and an “on demand” capability to upregulate clearance upon irritant exposure involving mucus hypersecretion and accelerated ciliary beat frequency (CBF) modulated by nitric oxide (NO). This study characterized these elements as well as cellular and exogenous NO concentrations subsequent to a single exposure to tobacco smoke (TS) or e-cigarette vapor (EV) on cultured human airway epithelium.Materials and methods: Air–liquid interface (ALI) airway epithelial cultures per nonsmoking human subjects were subjected to single TS or EV exposures. Measures of ciliary function and secretion were performed and cellular and exogenous NO concentrations under control and experimental conditions were assessed.Results: Both TS and EV exposures resulted similar patterns of decline in CBF within 1?min of the completion of exposure followed by a gradual return often exceeding baseline within 1?h. Post-exposure examination of exposed cultures suggested morphologic differences in secretory function relative to controls. The relative NO concentrations of TS and EV chamber air were sharply different with EV NO being only slightly elevated relative to cellular NO production.Discussion and conclusions: Epithelial remodeling and mucociliary dysfunction have been clearly associated with TS exposure. However, information contrasting epithelial structure/function following a single acute TS or EV exposure is limited. This study demonstrates a similar pattern of epithelial response to acute TS or EV exposure. Inasmuch as NO may contribute to an inflammatory milieu and generation of toxic metabolites, it is plausible that recurrent exposures over time may be contributory to chronic pathologies. 相似文献
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Luke PP Girvan AR Al Omar M Beasley KA Carson M 《The Canadian journal of urology》2004,11(5):2396-2400
We present the initial clinical experience using a robot to perform a laparoscopic dismembered pyeloplasty at a Canadian centre. Five patients were confirmed to have ureteropelvic junction obstructions through nuclear renography, cross sectional imaging and intravenous pyelography. After performing a retrograde ureteropyelography and double J stent placement, laparoscopic dismembered pyeloplasty was performed by a single surgeon at a remote workstation using the ZeusTM Telepresence Surgery System (Intuitive Surgicala). The mean total operative time was 225+/-48 minutes, anastomotic time was 71+/-16 minutes, and the mean time required to set-up the robot was 30+/-17 minutes. The estimated blood loss was less than 100 ml in each case. A mean total of 22+/-10 mg of morphine sulfate equivalents were used for analgesia, and the patients were discharged home after a mean of 58+/-10 hrs. There were no robotic failures, and all evaluable patients are free of pain and demonstrable obstruction. One patient developed a delayed urine leak, which resolved with percutaneous drainage. The robot provides the ability to perform complicated operations with precision through elimination of tremor, scaling of motion, and through the use of 'wristed' instruments that enhance the freedom of movement normally limited by straight-shafted laparoscopic needle drivers. The development of robotic telesurgery is still in its infancy, and the significance of its role in urologic surgery continues to be evaluated. 相似文献