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During the wet season of 2010, yellow fever virus (YFV) was detected in field-collected mosquitoes in the Kédougou region in southeastern Senegal. During this outbreak, we studied the association of the abundance of YFV-infected mosquitoes and land cover features to try and understand the dynamics of YFV transmission within the region. In total, 41,234 mosquito females were collected and tested for virus infection in 5,152 pools. YFV was detected in 67 pools; species including Aedes furcifer (52.2% of the infected pools), Ae. luteocephalus (31.3% of the infected pools), Ae. taylori (6.0% of the infected pools) and six other species (10.4% of the infected pools) captured in September (13.4%), October (70.1%), and November (16.4%). Spatially, YFV was detected from mosquitoes collected in all land cover classes but mainly, forest canopies (49.2%). Human infection is likely mediated by Ae. furcifer, the only species found infected with YFV within villages. Villages containing YFV-infected mosquitoes were significantly closer to large forests (> 2 ha) than villages in which no infected mosquitoes were detected.  相似文献   
23.
Artemisinin-based combination therapies (ACTs) are the first-line treatment of uncomplicated malaria. The public health benefit and safety of repeated administration of a given ACT are poorly studied. We conducted a randomized trial comparing artemether-lumefantrine, artesunate plus amodiaquine (AS+AQ) and artesunate plus sulfadoxine-pyrimethamine (AS+SP) in patients 6 months of age and older with uncomplicated malaria in Mali from July 2005 to July 2007. The patient received the same initial treatment of each subsequent uncomplicated malaria episode except for treatment failures where quinine was used. Overall, 780 patients were included. Patients in the AS+AQ and AS+SP arms had significantly less risk of having malaria episodes; risk ratio (RR) = 0.84 (P = 0.002) and RR = 0.80 (P = 0.001), respectively. The treatment efficacy was similar and above 95% in all arms. Although all drugs were highly efficacious and well tolerated, AS+AQ and AS+SP were associated with less episodes of malaria.  相似文献   
24.
We describe the investigation of speech automatisms in a man with progressive nonfluent aphasia and apraxias. Occurrence of the automatisms yes and right, were analysed across a range of speech tasks varying in length, propositionality, lexical and articulatory complexity, whether tasks engaged internal generation or external triggering and articulatory distortions, and while completing pantomimes/gestures. No differences were found in occurrence across most tasks but there was a significant interaction between automatism production and apraxic speech errors and during limb praxic tasks, suggesting that production of the automatism was unrelated to linguistic or lexical variables, but was related to the presence of speech apraxia coupled with disinhibition.  相似文献   
25.
目的:通过分析相关文献,总结心肺复苏后脑功能障碍的中医证型分布及用药规律。方法:采用"心肺复苏后脑功能障碍"或"复苏后脑功能障碍"或"复苏后脑损伤"或"脑功能障碍"或"脑损伤"或"心搏骤停后脑复苏"和主题词"中医"或"中药"或"中药治疗"或"中医治疗"或"中医证型"或"证候",在中国知网(CNKI)、维普、万方进行检索,根据纳入排除标准最终筛选文献24篇,将数据整理录入Excel 2007,并应用SPSS19.0统计软件进行分析。结果:中医证型出现频次前3位是阳气暴脱型、气虚血瘀型和气阴两脱型。方剂/中成药应用频次前3位分别是参附注射液、生脉注射液及川芎嗪注射液。单味中药的应用频次前6位分别是红参、附子、川芎、麦冬、五味子及当归。聚类分析显示了4组药物:(1)黄芩、板蓝根、珍珠母、水牛角、金银花;(2)川芎、赤芍、红花、当归、丹参、桔梗、柴胡、枳壳、人参、牛膝、生地黄;(3)麝香、冰片、栀子、郁金;(4)牛黄、黄连、朱砂、珍珠、雄黄。结论:心肺复苏后脑功能障碍的中医证型以虚证为主,用药多为补益类中成药注射液和中药,清热解毒类、活血化瘀类和解毒醒神类中药也有一定作用。  相似文献   
26.
Several impulsivity-related models have been applied to understanding the vulnerability to addiction. While there is a growing consensus that impulsivity is multifaceted, debate continues as to the precise number of facets and, more critically, which are most relevant to explaining the addiction-risk profile. In many ways, the current debate mirrors that which took place in the personality literature in the early 1990s (e.g., Eysenck's ‘Big Three’ versus Costa and McCrae's ‘Big Five’). Indeed, many elements of this debate are relevant to the current discussion of the role of impulsivity in addictive behavior. Specifically, 1) the use of factor analysis as an atheoretical ‘truth-grinding machine’; 2) whether additional facets add explanatory power over fewer; 3) the delineation of specific neurocognitive pathways from each facet to addictive behaviors, and; 4) the relative merit of ‘top-down’ versus ‘bottom-up’ approaches to the understanding of impulsivity. Ultimately, the utility of any model of impulsivity and addiction lies in its heuristic value and ability to integrate evidence from different levels of analysis. Here, we make the case that theoretically-driven, bottom-up models proposing two factors deliver the optimal balance of explanatory power, parsimony, and integration of evidence.  相似文献   
27.
Dengue virus (DENV) is the most widespread arthropod-borne virus, with the number and severity of outbreaks increasing worldwide in recent decades. Dengue is caused by genetically distinct serotypes, DENV-1–4. Here, we present data on DENV-1, isolated from patients with dengue fever during an outbreak in Senegal and Mali (Western Africa) in 2015–2019, that were analyzed by sequencing the envelope (E) gene. The emergence and the dynamics of DENV-1 in Western Africa were inferred by using maximum likelihood and Bayesian methods. The DENV-1 grouped into a monophyletic cluster that was closely related to those from Southeast Asia. The virus appears to have been introduced directly into Medina Gounass (Suburb of Dakar), Senegal (location probability = 0.301, posterior = 0.76). The introduction of the virus in Senegal occurred around 2014 (95% HPD = 2012.88–2014.84), and subsequently, the virus moved to regions within Senegal (e.g., Louga and Fatick), causing intense outbreaks in the subsequent years. The virus appears to have been introduced in Mali (a neighboring country) after its introduction in Senegal. In conclusion, we present evidence that the outbreak caused by DENV-1 in urban environments in Senegal and Mali after 2015 was caused by a single viral introduction from Asia.  相似文献   
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29.
T-lymphocyte subsets were studied in two patient groups: (1) 50 patients with homozygous sickle cell anaemia (SCA) (mean age 12 (range 3-32) years old) in good health at the time of the study who showed no infectious complication. (2) 50 patients (mean age 13 (range 4-29) years old) with normal haemoglobin rate. The global response revealed a significant increase in levels of CD3+ (P=0.04) and CD8+ (P=0.04) cells when compared with the control group, there was no significant difference in levels of CD4+ cells (P=0.05) between the two groups. However, there was a relationship between T-cell subpopulation levels and spleen status. The average values of T-cell subsets (CD4+ and CD8+) in patients with SCA-induced splenic defects (asplenic, splenomegaly or splenectomized patients) were significantly reduced when compared to SCA patients with normal spleens and the control groups. These data show that T-cell activity was reduced in patients with splenic defects. A correlation between splenic status and a perturbed host defence system in patients with SCA suggests that monitoring T-cell subsets might have prognostic value in the course of sickle cell disease.  相似文献   
30.
After a period of heavy rainfall, an outbreak of Rift Valley fever occurred in southern Mauritania during September–November 2012. A total of 41 human cases were confirmed, including 13 deaths, and 12 Rift Valley fever virus strains were isolated. Moudjeria and Temchecket Departments were the most affected areas.  相似文献   
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