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41.
Studying the effects of microgravity on cell differentiation will enhance our understanding of fundamental biology and is indispensable for a sustained space program. Rauscher murine erythroleukemic cells were chosen as a model system to study erythroid cell differentiation aboard the International Space Station because these cells undergo differentiation in response to the natural inducer, erythropoietin, as well as various chemical inducers. We have now developed a method to quantify hemoglobin in Rauscher cells after weeks of fixation and storage required for such space biology experiments. By exploiting the pseudoperoxidase activity of hemoglobin and by using reagents that yield a soluble chromophore that freely passes out of fixed cells, we developed a highly specific and sensitive assay applicable to cells fixed as long as 4 months.  相似文献   
42.
Long-term results of cervical interbody fusion with PMMA were evaluated in a retrospective study. X-ray films of 83 patients were obtainable. Post-operative follow-up in this series was between 15 and 20 years. The results show that PMMA is engrafted after about 2 years. Stable vertebral interbody fusion is obtained in about 90% of cases. Development of malignoma was not observed. Resorptive bone alterations, which can be seen in about 2% of cases one to two years after operation are shown not to be progressive. This process heals and stable fusion develops.  相似文献   
43.
儿童白内障术后远期结果的研究进展   总被引:1,自引:1,他引:0  
肖林 《眼视光学杂志》2007,9(2):142-144
本文对近几年一些学者对儿童白内障远期随访结果进行了综述和评价。手术时机选择、儿童特殊的屈光变化以及如何精确测定儿童植入人工晶状体性能及屈光度都对儿童白内障术后远期视功能产生影响。慢性青光眼是儿童白内障术后远期丧失视力的主要原因。长期弱视治疗是获得手术成功的保证之一。因此,要真正获得有用的视功能,应重视儿童白内障手术后的后续治疗,并提议应建立完善的白内障术后追踪随访和弱视治疗机构。  相似文献   
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45.
The primary purpose of this study was to apply an occupational therapy programme for social skills training based on a cognitive-behavioural frame of reference to individuals with long-term mental illness. The goal of the social skills training group was to enable patients to develop verbal and non-verbal communication skills that could be generalised to everyday interpersonal encounters. A case example of the application of social skills training with a 38-year-old single male with a diagnosis of paranoid schizophrenia is described. The Group-Interaction Skills Survey developed by the author served as an outcome measure. Qualitative data confirmed the researcher's hypothesis that individuals with long-term mental illness can benefit from social skills training using a combination of role-playing, sociodrama, videotape recordings and creative media. Copyright © 1996 Whurr Publishers Ltd.  相似文献   
46.
Recent behavioural studies have provided evidence that the amygdala modulates hippocampal-dependent memory. To test the possibility that the amygdala modulates hippocampal synaptic plasticity, we investigated the effects of surgical lesions of the amygdaloid nuclei on the induction of long-term potentiation (LTP) in the dentate gyrus of anaesthetized rats. Previously we reported that LTP in the dentate gyrus was attenuated by lesion of the basolateral amygdala, but was not affected by lesion of the central amygdala. In the present study, dentate gyrus LTP was significantly attenuated by basomedial amygdala lesion but not by medial amygdala lesion. These results suggest that, among the amygdaloid nuclei, the basomedial and basolateral nuclei are involved in the modulation of hippocampal plasticity. The roles of the basomedial and basolateral amygdala were further supported by experiments examining the effects of electrical stimulation of these nuclei. High-frequency stimulation of the basomedial amygdala alone did not induce dentate gyrus LTP, but when applied at the same time as tetanic stimulation of the perforant path increased the magnitude of the dentate gyrus LTP. Similarly, high-frequency stimulation of the basolateral amygdala enhanced LTP induced by tetanic stimulation of the perforant path. Furthermore, facilitation of dentate gyrus LTP by basomedial or basolateral amygdala stimulation was observed even in rats lesioned in either amygdala, suggesting that neurons in the basomedial and basolateral amygdala can modulate dentate gyrus LTP independently. Activity-dependent facilitation of hippocampal plasticity by the basomedial and basolateral amygdala may underlie memory processing associated with emotion.  相似文献   
47.
背景 农村订单定向医学生(简称定向医学生)的免费培养工作是缓解农村地区基层医生匮乏、提升基层医疗卫生队伍整体素质和水平的重要举措。目的 探索我国定向医学生培养的研究热点、研究动态和未来趋势,为后续研究提供参考。方法 于2022-02-15,在中国知网、万方数据知识服务平台、维普网中检索2010-01-01至2021-12-31发表的关于定向医学生培养相关论文,统计其发文量,运用Cite Space软件对样本文献作者、研究机构、关键词进行知识图谱的可视化分析。结果 共纳入598篇文献,关于定向医学生培养研究的文献量呈上升趋势,2018年达到历年顶峰(n=81)。该领域存在5个大的作者群,发文量排在前3位的机构为赣南医学院[113篇(18.9%)]、广西医科大学[40篇(6.7%)]及新乡医学院[28篇(4.7%)]。关键词词频排在前3位的分别是“订单定向”(70次)、“定向生”(57次)、“人才培养”(44次)。关键词聚类图谱得到“#0学习动力”“#1教学模式”“#2定向培养”“#3影响因素”“#4全科医学”“#5基层”“#6医学院”“#7医学生”8个聚类主题。最强突现词显示,排在前3位...  相似文献   
48.
[目的] 探索甘草地上部分活性部位对小鼠的急性毒性及大鼠的长期毒性,评价其安全性,为合理开发利用甘草地上部分资源以及临床应用提供可靠的理论依据。[方法] 甘草地上部分活性部位33.2 g/kg灌胃给予昆明种小鼠,24 h内两次(间隔5 h)经口灌胃给予受试物,持续观察14 d内小鼠的急性毒性反应;SD大鼠随机分为对照组和甘草地上部分低、中、高剂量组,按8.3、16.6、33.2 g/kg剂量连续灌胃甘草地上部分活性部位90 d,观察大鼠的一般状况,并分别于给药后45、90 d进行血液学指标检测与血清生化指标检测,给药后90 d进行大体解剖及病理学检查,观察甘草地上部分活性部位的长期毒性反应。[结果] 急性毒性实验中小鼠的一般状态、饮食、分泌物、排便未见异常,无小鼠死亡,肉眼尸检心、肝、脾等主要脏器组织未见明显异常;长期毒性实验中,各组大鼠与对照组比较,一般状况、血液学及血清生化指标未见明显差异;病理检查未见主要脏器组织形态学改变。[结论] 甘草地上部分活性部位无急性毒性和长期毒性,在治疗剂量范围内用药安全性高。  相似文献   
49.
目的 探讨重症监护病房(ICU)重症脓毒症患者远期负性情绪发生率及相关因素。方法 选取2019年1月—2020年12月南阳市第一人民医院入住ICU的99例重症脓毒症患者作为研究对象,均随访2年。将并发焦虑抑郁的患者作为负性情绪组,未并发焦虑抑郁的患者作为非负性情绪组,分别有30和69例。分析两组患者年龄、性别、种族、体重、入院临床特征(住院时长、ICU时长及血清乳酸、降钙素、C反应蛋白水平)、入院诊断疾病(心血管系统、呼吸系统、传染病、其他)、疾病严重程度[急性生理学和慢性健康评估Ⅱ(APACHEⅡ)评分、脓毒症相关器官衰竭评估(SOFA)评分、感染性休克]、器官支持情况[机械通气、连续性肾脏替代疗法(CRRTn)]、入住ICU前72 h是否使用皮质类固醇及在ICU住院期间咪达唑仑、芬太尼、多巴酚丁胺、去甲肾上腺素和氟哌啶醇的累积剂量等基线特征。结果 两组患者性别构成、年龄、种族、体重、心血管系统疾病、呼吸系统疾病、传染病、其他疾病、APACHEⅡ评分、SOFA评分、机械通气、CRRTn、入住ICU前72 h使用皮质类固醇、咪达唑仑、多巴酚丁胺、去甲肾上腺素的累积剂量比较,差异均无统计...  相似文献   
50.
The quantity and quality of published research in the field of Virology by different world regions was estimated in this study. Using the PubMed database, articles from journals included in the "Virology" category of the "Journal Citation Reports" database of the Institute for Scientific Information for the period 1995-2003 were retrieved. The world was divided into nine regions based on geographic, economic, and scientific criteria. Data on the country of origin of the research was available for 33,425 out of 33,712 articles (99.2% of all articles from the included journals). USA exceeds all other world regions in research production for the period studied (42% of total articles), with Western Europe ranking second (35.7%). The mean impact factor in articles published in Virology journals was highest for the USA (4.60), while it was 3.90 for Western Europe and 3.22 for the rest of the world (seven regions combined). USA and Canada ranked first in research productivity when both gross national income per capita (GNIPC) and population were taken into account. The results of this analysis show a distressing fact; the absolute and relative production of research in the field of Virology by the developing regions is very low, although viral diseases cause considerable morbidity and mortality in these areas. It is evident from this study that developing regions need more help from the developed regions to enhance research infrastructure.  相似文献   
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