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1.
对2010年1月—2016年7月重庆市中毒救治指定医疗机构收治的2 497例中毒患者进行回顾性分析。结果显示,中毒患者中男性1 230例(49.3%)、女性1 267例(50.7%);分布最多的3个年龄段依次是41~50岁(18.5%)、≤10岁(16.4%)和21~30岁(13.0%);死亡16例,病死率0.6%。中毒类型构成排前三位的是细菌(33.8%)、化学品(32.2%)、植物(14.8%)。中毒预后多因素Logistic回归分析结果显示重度中毒患者结局死亡的可能性是轻度患者的1 102倍。提示重庆市应重点关注农村地区41~50岁人群的细菌、化学品、药物中毒,同时应该加强儿童中毒防控工作。  相似文献   
2.
PurposeThe purpose of this study was to determine whether computed tomography (CT)-based machine learning of radiomics features could help distinguish autoimmune pancreatitis (AIP) from pancreatic ductal adenocarcinoma (PDAC).Materials and MethodsEighty-nine patients with AIP (65 men, 24 women; mean age, 59.7 ± 13.9 [SD] years; range: 21–83 years) and 93 patients with PDAC (68 men, 25 women; mean age, 60.1 ± 12.3 [SD] years; range: 36–86 years) were retrospectively included. All patients had dedicated dual-phase pancreatic protocol CT between 2004 and 2018. Thin-slice images (0.75/0.5 mm thickness/increment) were compared with thick-slices images (3 or 5 mm thickness/increment). Pancreatic regions involved by PDAC or AIP (areas of enlargement, altered enhancement, effacement of pancreatic duct) as well as uninvolved parenchyma were segmented as three-dimensional volumes. Four hundred and thirty-one radiomics features were extracted and a random forest was used to distinguish AIP from PDAC. CT data of 60 AIP and 60 PDAC patients were used for training and those of 29 AIP and 33 PDAC independent patients were used for testing.ResultsThe pancreas was diffusely involved in 37 (37/89; 41.6%) patients with AIP and not diffusely in 52 (52/89; 58.4%) patients. Using machine learning, 95.2% (59/62; 95% confidence interval [CI]: 89.8–100%), 83.9% (52:67; 95% CI: 74.7–93.0%) and 77.4% (48/62; 95% CI: 67.0–87.8%) of the 62 test patients were correctly classified as either having PDAC or AIP with thin-slice venous phase, thin-slice arterial phase, and thick-slice venous phase CT, respectively. Three of the 29 patients with AIP (3/29; 10.3%) were incorrectly classified as having PDAC but all 33 patients with PDAC (33/33; 100%) were correctly classified with thin-slice venous phase with 89.7% sensitivity (26/29; 95% CI: 78.6–100%) and 100% specificity (33/33; 95% CI: 93–100%) for the diagnosis of AIP, 95.2% accuracy (59/62; 95% CI: 89.8–100%) and area under the curve of 0.975 (95% CI: 0.936–1.0).ConclusionsRadiomic features help differentiate AIP from PDAC with an overall accuracy of 95.2%.  相似文献   
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学习困难儿童智力及记忆力特征分析   总被引:4,自引:3,他引:1  
目的探讨学习困难儿童的智力、记忆力特征。方法学习困难(LD)根据ICD-10五条诊断标准,精神发育迟滞(MR)根据国际疾病分类第10版(ICD-10)诊断标准,分为实验组LD组;对照组a.正常组,b.弱智组。采用中国韦氏儿童智力量表进行智力测验,记忆力测验采用中国科学研究院编制的临床记忆量表。结果LD组与正常对照组在语言智商、操作智商、总智商[(86.23±10.65)分,(87.44±12.59)分,(84.09±13.96)分vs(102.27±10.21)分,(103.22±11.65)分,(103.28±9.88)分]及分测验值差异均有显著性(P<0.01);LD组儿童VIQ与PIQ相距一个标准差以上的比率明显高于对照组(2=9.29,P<0.01),也较MR对照组多(2=4.29,P<0.05)。LD组记忆商(MQ)明显低于正常对照组(P<0.01)。结论LD儿童智商、记忆商水平低于正常儿童,且存在明显智力结构发展不平衡。  相似文献   
6.
Morphine (8–100 mg/kg IP) induces place preference conditioning in mice. The effect of two different periods of isolation (15 and 30 days) was examined. Mice isolated for 15 days but not 30 days exhibited place preference conditioning to morphine (8 mg/kg). After 30 days of isolation morphine could not induce place preference conditioning with the following doses (8, 16, 64, 100 mg/kg). Social regrouping of male mice previously isolated for 30 days with naive female mice for 15 or 30 days resulted in a reappearance of the conditioned place preference to morphine (16 mg/kg). The specificity of this associative deficit was examined by testing learning in isolated compared to non-isolated mice in two distinct settings: escape learning in the Morris water maze and passive avoidance acquisition and retention. On the Morris water maze isolated mice did not differ from non-isolated mice regarding place learning, the probe trial or extinction. Isolated mice were unimpaired in passive avoidance acquisition and retention. It was concluded that the deficits in place preference conditioning were not the result of a global learning impairment in isolated mice. Received: 10 April 1996 /Final version: 20 September 1996  相似文献   
7.
心理因素对小学生脑力工作能力影响的研究   总被引:4,自引:2,他引:2  
采用横断面研究方法,对180名小学三年级学生脑力工作能力与其智力、性格、学习动机等心理因素和学习、睡眠时间等作息因素的关系进行分析研究。验证了学习、睡眠时间是影响学生脑力工作能力重要的外部因素;脑力工作能力与智力和学习成绩呈正相关。学生自身的心理因素中,学习动机对脑力工作能力有重要影响,所以激发和强化学生的学习动机,是保持和提高学生学习工作能力的有效手段;而性格内外向性、情绪稳定性等因素,对脑力工作能力的影响不明显。  相似文献   
8.
Neural plasticity of modality-nonspecific and modality-specific memory and learning abilities pertains to fluid intelligence and crystallized intelligence, respectively. The limbic system with the novelty neurons of the hippocampus interacts with the prefrontal cortex optimization of the orienting reflex and voluntary attention. Brain-derived neurotrophic factor produced by novelty neurons of the hippocampus contributes to long-term memory formation and improves learning abilities in a wide range of disciplines. Synergistic combination of stimulation with “analytical-specific visual perceptual patterns” and “optimally high” physiological activation of the bilateral electrodermal system optimizes the limbic system and prefrontal cortex activity as demonstrated by enhanced prefrontal N450 ERPs to a memory workload paradigm. This is accompanied by improvements in auditory retention tasks, word memorization, higher school achievement and marks, and an amelioration of “analytical-specific perceptual skills” as measured by the Mangina-Test. Intracerebral ERPs to a memory workload paradigm contributed to the elucidation of limbic structures and neocortical sites involved in memory workload processes. The progressive degeneration of these same structures causes the gradual decline of memory functions observed in early Alzheimer's disease. Research findings indicate that ERPs elicited by a memory workload paradigm are sensitive markers for diagnosis, treatment and clinical follow-up of early Alzheimer's patients. In addition, ERPs provide objective measurement of cholinergic medication effects on cerebral functions involved in memory processes through neuropsychophysiological parameters.  相似文献   
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牟英 《药学教育》2010,26(2):54-55
通过具体的实验数据,讨论在药代动力学实验中如何加入曲线下面积(AUC)的计算,以帮助学生理解并掌握这一概念;在实验室设置不同剂量组,给药后比较剂量与浓度是否呈等比例关系,以此加深学生对于一级动力学消除及其临床意义的理解。  相似文献   
10.
Summary Bayesian analysis is given of a random effects binary probit model that allows for heteroscedasticity. Real and simulated examples illustrate the approach and show that ignoring heteroscedasticity when it exists may lead to biased estimates and poor prediction. The computation is carried out by an efficient Markov chain Monte Carlo sampling scheme that generates the parameters in blocks. We use the Bayes factor, cross‐validation of the predictive density, the deviance information criterion and Receiver Operating Characteristic (ROC) curves for model comparison.  相似文献   
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