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汉语成语结尾字事件相关电位N400的研究   总被引:10,自引:2,他引:8  
陈璇  宋旻烨 《广东医学》2003,24(7):711-713
目的 通过记录汉语成语结尾字匹配与不匹配事件相关电位N400的变化,探讨视觉词语认知模式及汉字认知加工特征。方法发采用南方医院研制的事件相关电位仪,对15例21—36岁健康人右利手受试者中,进行汉语成语正常结尾字(匹配字)与歧义字(不匹配字)N400的研究。结果 受试者对结尾词匹配与不匹配组的N400成分在潜伏期及波幅差异有显著性(P≤0.01),不匹配组的N400波幅高,潜伏期长。N400广泛分布于各区,左侧比右侧波幅偏高。结论 汉语成语结尾字匹配与不匹配的N400与字词认知中的语义密切相关,有一定的临床价值,可用于临床多种伴有语言障碍疾病的评估。  相似文献   
123.
目的 探讨在少、弱精子症中精子形态缺陷类型及其发生率.方法 对精液常规和改良巴氏染色检查的结果进行统计学分析.结果 (1)男性不育症中畸形精子症的发生率约为75%;精子头部缺陷的发生率约为70%,各种头部缺陷中空泡头畸形的发生率占首位,约为20%.(2)少精子症患者的正常形态精子百分率的中位数约为2.97%(P=0),弱精子症患者的中位数为6.67%(P=0.003).结论 (1)精子头部缺陷是精子畸形的主要类型;(2)少、弱精子症的畸形精子比例升高;(3)精子形态缺陷分析对选择辅助助孕方式具有应用价值.  相似文献   
124.
目的探讨成人肾母细胞瘤的诊断和治疗方法。方法回顾性分析9例成人肾母细胞瘤的临床表现、分期、治疗及预后。结果9例患者按照美国国家肾母细胞瘤研究组(National Wilms Tumor Study,NWTS)分期:Ⅰ期3例,Ⅱ期3例,Ⅲ期2例,Ⅳ期1例。9例均行肾切除术,其中术前分别辅以化疗1例、放疗1例、肾动脉介入栓塞化疗2例。9例术后辅以放疗和化疗。8例获得随访,随访1-6年,7例生存。结论成人肾母细胞瘤是一种比较少见的恶性肿瘤,早期诊断、手术治疗、辅以放疗和化疗等可明显提高治愈率并改善其预后。  相似文献   
125.
Myocardial abscess is usually resulted from the septicemia ofvarious microorganisms such as Candida, Staphylococcus, Aspergillus,Streptococcus, and Salmonella species. Since  相似文献   
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Objective: To explore the therapeutic methods, surgical indications and clinical practice of minimally invasive surgery on traumatic epidural hematoma (EDH). Methods: Retrospective study was made on 135 patients with traumatic EDH admitted into our hospital from June 2002 to August 2005. Sixty-five patients were treated with mini-invasive negative pressure drainage (treatment group), 70 patients with comparable condition used traditional craniotomy (control group ). The mean time of operation, average days in hospital, expenditure and prognosis of two groups were recorded and analyzed. Results: There was no significant difference in therapeutic efficacy between two groups. Patients in treatment group had a shorter hospital stay and less expenditure than those in control group. Conclusion: Mini-invasive negative pressure drainage is simple, effective, economical and applicable to some traumatic EDH patients.  相似文献   
128.
This study was undertaken to compare the clinical and radiological results achieved using navigation-assisted minimally invasive surgery (NA-MIS) and conventional (CON) techniques in 42 bilateral total knee arthroplasty (TKA) patients with a minimum follow-up of one year. Clinical evaluations were performed using range of motion (ROM), Hospital for Special Surgery (HSS) scores, and Western Ontario and McMaster University (WOMAC) scores (pain, functional, and total) at 3, 6 and 9 months and one year postoperatively. Patients' subjective preferences and radiological indices, including mechanical axis and coronal inclinations of the prostheses, were compared at one year postoperatively. NA-MIS TKA yielded better HSS and WOMAC total scores than CON TKA up to six months, and a better WOMAC pain score up to 9 months. However, these differences were not significant at one year postoperatively. ROM was comparable in both groups at all times, but more patients preferred the NA-MIS side to the CON side. Radiological results showed no differences in mean values between the two surgical groups, although the NA-MIS group contained fewer outliers than the CON group. In conclusion, NA-MIS TKA was associated with better clinical results up to 6 or 9 months after surgery, giving more accurate leg alignment than CON TKA.  相似文献   
129.
Although breast milk is recommended as the optimal source of infant nutrition, breastfeeding initiation is below recommended levels, especially among teenage mothers. Breastfeeding initiation rates among Michigan (US) teenage mothers (12-19 y) were compared by demographics and health behaviors. Multivariate analyses determined which factors were significant independent predictors of breastfeeding initiation among teenage mothers enrolled prenatally in the Michigan Special Supplemental Nutrition Program for Women, Infants, and Children (WIC) program in 1995. Significant predictors independently associated with breastfeeding initiation were race/ethnicity, education, marital status, postpartum anemia status, parity, prenatal trimester of WIC enrollment, and smoking. The strongest predictor of breastfeeding initiation differed for white mothers (positive predictor: education beyond high school [OR = 3.13]) and black mothers (negative predictor: multiparous [OR = 0.25]). Initiation rates for this population of teenage mothers fall below the national average for mothers of all ages and the US Healthy People 2010 goals. Research is needed concerning how breastfeeding support and education can be improved to reach the US national health goals.  相似文献   
130.
It has been suggested that apparent diffusion coefficient (ADC) contrast can be sensitive to cerebral blood flow (CBF) changes during brain activation. However, current ADC imaging techniques have an inherently low temporal resolution due to the requirement of multiple acquisitions with different b-factors, as well as potential confounds from cross talk between the deoxyhemoglobin-induced background gradients and the externally applied diffusion-weighting gradients. In this report a new method is proposed and implemented that addresses these two limitations. Specifically, a single-shot pulse sequence that sequentially acquires one gradient-echo (GRE) and two diffusion-weighted spin-echo (SE) images was developed. In addition, the diffusion-weighting gradient waveform was numerically optimized to null the cross terms with the deoxyhemoglobin-induced background gradients to fully isolate the effect of diffusion weighting from that of oxygenation-level changes. The experimental results show that this new single-shot method can acquire ADC maps with sufficient signal-to-noise ratio (SNR), and establish its practical utility in functional MRI (fMRI) to complement the blood oxygenation level-dependent (BOLD) technique and provide differential sensitivity for different vasculatures to better localize neural activity originating from the small vessels.  相似文献   
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