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51.
The geographic range of Zika virus (ZIKV) has expanded from Asia to the Americas, leading to the 2015–2016 pandemic with enhanced neurovirulence. At present, ZIKV is continuously circulating in many Southeast Asian countries. Unfortunately, the persistent evolution of ZIKV in Southeast Asia and its influence on the biological characteristics of the virus remain incompletely understood. In this study, the in vitro and in vivo properties of a new ZIKV isolate obtained from Cambodia in 2019 (CAM/2019) were characterized and compared with those of the Cambodian strain (CAM/2010). Compared with CAM/2010, the CAM/2019 virus showed similar plaque morphology and growth curves in cell cultures and induced comparable viremia and organ viral loads profiles in both BALB/c and A129 (IFNAR1−/−) mice upon intraperitoneal (i.p.) inoculation. Remarkably, the CAM/2019 virus exhibited enhanced neurovirulence in neonatal mice compared with CAM/2010, with a 74-fold reduction in the 50% lethal dose (LD50). Consistently, CAM/2019 produced higher viral loads in the brains of BALB/c neonatal mice than CAM/2010 did. Sequence alignment showed that the CAM/2019 virus has acquired 12 amino acid substitutions, several of which were found to be associated with neurovirulence. In particular, the CAM/2019 virus shared an A1204T substitution in NS2A with the Thai isolate SI-BKK02 that was isolated from a microcephaly case. Taken together, our results indicate that a ZIKV strain isolated with specific mutations has emerged in Cambodia, highlighting the need for extensive molecular and disease surveillance in Cambodia and other Asian countries.  相似文献   
52.
为探讨狼疮性肾炎并发急性肾功能衰竭的危险因素,收集了符合狼疮性肾炎并发急性肾功能衰竭的病例26例,与未发生急性肾功能衰竭的狼疮性肾炎30例进行临床病理分析。结果:狼疮性肾炎并发急性肾功能衰竭常发生在具有临床活动指标及病理活动指标的患者,病理类型以Ⅳ型、Ⅴ型为主,其诱因有感染、不规则的激素治疗、劳累及日晒。结果表明:控制狼疮性肾炎的活动,避免诱发因素,是防止急性肾功能衰竭发生的重要环节。  相似文献   
53.
Objectives: Injuries are the leading killer of young persons in the United States, yet significant gaps in our understanding of this cause of death remain. By examining the independent influences of race, education, income, household structure, and residential location on injury mortality in young persons, this study addresses these gaps. Method: Using data from the National Longitudinal Mortality Study, survival analysis is used to examine the injury mortality risk faced by 0 to 17 year olds over a nine-year follow-up period. Separate models are estimated for homicide, suicide, unintentional injury deaths, and all injury deaths. Results: Household head's education has an independent effect on youth homicide and unintentional injury mortality risk. By contrast, family income and household structure do not have independent effects on any of the injury outcomes. Finally, much of the excess homicide risk faced by young African-Americans is explained by underlying racial differentials in socioeco-nomic status, household structure, and residential location. Conclusions: By finding an independent effect of household head's education on youth mortality risk from homicide and unintentional injuries, this study adds to the large body of evidence linking socioeconomic differentials to inequality in life chances.  相似文献   
54.
Fluoride salts are widely used in Europe in the treatment of established osteoporosis with crush fractures for their ability to increase trabecular bone mass. However, in the United States fluorides are still regarded as an experimental drug. In a prospective, randomized study we compared the fluoride pharmacokinetics of enteric-coated sodium fluoride and disodium monofluorophosphate calcium carbonate (MFP-Ca) over the period of 76 h. Twenty subjects (12 females, 8 males), aged 35–80 years, free of gastrointestinal disorders, renal impairment, and liver disease and without prior fluoride intake entered the study. Ten subjects received NaF (11.3 mg fluoride) twice a day and the other ten MFP-Ca (13.2 mg fluoride) twice a day. During the study period of 76 h the patient's usual food intake was not changed. Serum fluoride levels were determined using an ion sensitive electrode. After intake of a single drug preparation of MFPCa or NaF, MFP-Ca showed a significantly shorter lag time of absorption and a significantly higher maximal serum fluoride concentration than NaF (P<0.01). A comparison of fluoride cumulative characteristics of both drugs showed virtually identical serum fluoride levels before intake of the morning dose on all 4 study days, whereas serum fluoride concentrations measured 4 h afterwards were significantly higher for MFP-Ca than for NaF. These data provide evidence of high peak serum fluoride levels for MFP-Ca, whereas only small peak-to-trough fluctuations are seen for NaF.Abbreviations MFP-Ca disodium monofluorophosphate-calcium carbonate - C max maximum drug concentration - T max lag time of maximum drug concentration - AUC area under the serum concentration versus time curve Correspondence to: L. Erlacher  相似文献   
55.
本文对富源县阿依村特定人群肺癌的流行病学特征及环境致癌因素进行调查研究。研究了该村1986~1996年肺癌调整死亡率的水平,变化趋势、死亡专率及性别比值。该村肺癌死亡率高、波动性大。男性肺癌调整死亡率高于宣威肺癌高发区1.9倍,女性肺癌调整死亡率接近宣威肺癌高发区的水平,男女合计肺癌调整死亡率高于我国重庆、上海、沈阳、大连、南京、天津、广州等工业城市9.7~12.0倍。男性高于女性2.4倍。死亡高峰年龄男女性均始于30~岁年龄组。以居民群体为暴露单位,采集了该村火塘燃烧室、地炉燃烧室、室外空气中颗粒物及有害气体样品,检测其TSP、IP、BaP、SO2浓度,结果显示上述4项污染物的浓度均是火塘燃烧室高于地炉燃烧室而室外最低。γ辐射火塘燃烧室显著高于地炉燃烧室。IP提取物的致突变活性,火塘燃烧室高于地炉燃烧室高于室外。对该村居民改炉改灶降低室内空气中污染物的浓度及致突变活性的效果进行了评定。  相似文献   
56.
A new multidimensional movement analysis system was used to record limb tremor over six degrees-of-freedom, and signal processing techniques were explored to develop a suitable classification method to distinguish between different types of tremor. The specific aims were to investigate the ability of the system to screen for differences between normal subjects and a group of neurological patients, and then to differentiate between three diagnostic groups of patients.

Postural tremor at the hand was recorded in normal subjects (n=24) and patients with essential tremor (n=21), multiple sclerosis (n=17) and parkinsonism (n=19). Data were collected using a 3Space Fastrak® (Polhemus, Inc.) over six degrees-of-freedom (three translational directions and three rotations). Spectral estimates produced measures of tremor frequency and amplitude. Mathematical models of the data, using autoregressive modelling and K-nearest neighbour classification, produced parameters used to classify, (1) the normal subjects and 24 patients (using the three rotational movements), and (2) the three patient groups (using all six movement directions). Results were given in terms of the probability of each subject belonging to the groups being classified.

Tremor frequency and amplitude showed large overlap between the groups. The screening classification produced high probabilities of correctly classifying normal subjects (>70%) and patients (>70%). The diagnostic classification produced clear differences between the patient groups (60% for essential tremor, 80% for multiple sclerosis and 60% for parkinsonism).

The ability of this assessment technique to distinguish between postural tremor in normal subjects and neurological patients suggests that it could be developed as a screening tool. Classification of tremors between the patients groups, with a high degree of sensitivity, indicates the potential for further development of the system as a diagnostic aid.  相似文献   

57.
对四个单位保种的S180 细胞经KM 小鼠腹腔传代,体外培养加秋水仙碱,涂片、染色后,显微镜下计数染色体数目:腹水传代的S180 细胞,用70 % 乙醇固定,流式细胞仪测DNA 含量。结果如下:本学部( 本部) ,中国医学科学院药物所( 药物所) ,武汉大学保种中心( 武汉大学) 和北京市肿瘤所( 肿瘤所) 保种的S180 细胞株,其染色体均数分别为62-8 ±22-8 ,69-1 ±21-2,39-9 ±8-26 ,58-7±9-75 条。四单位S180 细胞株染色体数做方差分析表明,除肿瘤所与本部外,其它两单位比较均有显著统计学差异(P< 0-01) 。直方图分析显示主流染色体范围分别为56 ~60 ,61 ~65,41 ~45,61 ~65 条。流式细胞术DNA 含量分析表明肿瘤所S180 DNA含量最多,武汉大学保种的S180 细胞的DNA含量最少。这些结果均证明四个单位的S180 细胞株在一些方面已出现显著差异。  相似文献   
58.
家庭环境因素对青少年精神分裂症的影响   总被引:4,自引:0,他引:4  
目的 探讨精神分裂症和家庭环境的关系。方法 用自编“家庭环境调查问卷”、修订的父母养育方式评价量表(EMBU)对82例青少年患者和82个正常青少年家庭进行调查,用Camberwell家庭会谈表(CFI)评定患者亲属的情感表达(EE)水平。结果 (1)病例组父母关系、亲子关系差,父母有不良行为习惯者多(P〈0.05);家庭性患者父母文化水平低、经济收入低、健康状况差(P〈0.01)。(2)病例组父母  相似文献   
59.
腭裂术后语音的实验研究   总被引:2,自引:0,他引:2  
提供一种易被患者接受、无害、科学客观的腭裂术后语音缺陷的诊断方法。方法:随机选择各种腭裂类型的腭裂术后患者47例,将其语音输入KAY7800语图仪,分析其语音特点和语图表现。结果:腭裂术后语音有3大语音特点和8类语图表现。3大语音特点是残缺、代偿和干扰;8类语图表现是辅音残缺、共振峰残缺、送气代偿、浊化代偿、喉塞代偿、鼻音干扰元音、鼻音干扰辅音和噪音干扰。结论:腭裂术后患者口腔内的能量不足是造成以上语音缺陷的主要原因。  相似文献   
60.
This study examines the relationships among demographic factors, combat experiences, personality characteristics, altruism, and posttraumatic stress disorder (PTSD) symptomatology. Participants were Vietnam War veterans currently undergoing treatment for PTSD. The developmental level of internalized schemas of interpersonal relations (object relatedness) and the altruistic intent to help were significant predictors of PTSD symptomatology, with lower levels of symptomatology associated with higher levels of altruism. Results indicated that predispositional variables and altruistic intentions may be important factors to consider in designing and implementing treatment programs for chronically impaired veterans with PTSD.  相似文献   
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