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31.
本文于1993年4月调查了新疆拜城县重病区查尔齐农场中与中病区赛里木乡的饮水,土壤,粮食,学龄儿童头发中Zn,Cu,Mn,Ca,Li,Se6种元素无机元素的含量。结果表明,重病区小麦中Ca的含量显著高于中病区(P〈0.05),重病区饮水及小麦中Mn的含量显著低于中病区(P〈0.05)。这些结果揭示重病区查尔齐与中病区赛里木乡的病情相比较,除缺碘较为严重这一主要原因之外,高Ca,低Mn也可能与查尔齐 相似文献
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本文用气相色谱法对居住福州、长乐、宁化三个地区270名健康人群发铬含量进行调查。结果表明:福州地区发铬值高于其它两地区,并有非常显著性差异。总体发铬算术平均数与国内外部分地区所报导的结果比较接近,但在性别及年龄间差异不明显。对三个地区发铬值与当地土壤铬含量进行相关分析,r=0.9978,二者呈正相关,并有非常显著性意义。 相似文献
34.
Anxiolytic benzodiazepines have been shown to impair place learning in the Morris water maze. However, a clear-cut demonstration of a direct and specific effect on mnemonic processes has not yet been offered. In the present study, the effects of diazepam on place navigation in the Morris water maze were studied in rats. Three conditions were examined: learning, reversal learning and learning after familiarisation of animals with the maze. In view of the anxiolytic and sedative properties of diazepam, appropriate doses of the drug, i.e. those that produced an anxiolytic effect but no major motor impairment, were initially selected in the water-lick conflict and rotarod tests, respectively. Doses of 2.5 and 5 mg/kg PO increased punished drinking in the water-lick conflict test without significantly decreasing rotarod performance. These doses were then used to assess the effects of diazepam on spatial behaviour. Diazepam, at both doses, impaired place learning in behaviourally naive rats. Such an effect appeared to be transient: diazepam-treated rats eventually reached control performance. Moreover, analysis of the probe trial at the end of training revealed adoption of a spatial strategy to locate the submerged platform. Neither reversal learning nor learning after familiarisation was affected. These results do not replicate previous findings in the Morris water maze and provide some evidence that the diazepam-induced place learning deficit may be primarily anxiolytic in nature. 相似文献
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宝鸡市城市饮用水与人群健康效应的调查研究 总被引:1,自引:1,他引:0
本文通过对宝鸡市居民饮自来水和自备井水的人群进行了回顾性和前瞻性调查分析,结果发现,饮自来水与饮未经处理自备井水明显的差异。即调查组(饮自来水)肠道传染病发病率为4.22%和6.82%,对照组(饮自备井水)发病率为7.71%和11.56%经卡方检验P<0.05,差异有显著性。从发病病种来看,调查组和对照组均以腹泻为主,其次为痢疾和肝炎,发病率分别是:腹泻,调查组为35.59‰和63.00‰,对照组 相似文献
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TAMÁS HENICS & DENYS N. WHEATLEY 《International journal of experimental pathology》1997,78(5):343-354
Hep-2, human epithelial carcinoma cells, and human foreskin fibroblasts (FF9 and FF13) were exposed to either an ultrafiltrate (< 50 kD) of human sera or the weak base, procaine hydrochloride, to induce reversible cytoplasmic vacuolization. The formation of vacuoles was shown not to be due to imbibition of medium. Ultrastructural details obtained from various stages of vacuole formation were compared. In both cases of induction vacuoles were irregular and often appeared membraneless, with little in the way of electron-dense content. They started to form in the perinuclear cytoplasm and progressed towards the periphery. Osmotic stress was not involved since mitochondria remained normal throughout a vacuolization episode.
Vacuoles were often seen in close contact with filamentous structures, and this association remained detectable at late stages of the phenomenon. Fluorescent visualization of F-actin confirmed that the vacuoles were frequently bordered by microfilaments. No major metabolic impairment was apparent in vacuolized cells as judged by protein synthesis measurements, but nuclear fluorescence (DNA content) and forward light scatter (nuclear volume) by flow cytometric analysis suggested late S phase and G2 retardation.1 H-nmr relaxation measurements indicated intracellular water restricted in motional characteristics in vacuolized cells. The possibility of a restricted cytoplasmic phase separation as part of a transient adaptation response is raised, and a hypothesis to explain the findings is discussed. 相似文献
Vacuoles were often seen in close contact with filamentous structures, and this association remained detectable at late stages of the phenomenon. Fluorescent visualization of F-actin confirmed that the vacuoles were frequently bordered by microfilaments. No major metabolic impairment was apparent in vacuolized cells as judged by protein synthesis measurements, but nuclear fluorescence (DNA content) and forward light scatter (nuclear volume) by flow cytometric analysis suggested late S phase and G2 retardation.
39.
化学品环境管理与水生实验动物 总被引:3,自引:1,他引:2
从分析化学品的特性入手,在概述化学品的环境管理对水生实验生物需求和国内外水生实验生物发展现状的基础上,从加强化学品环境管理的科学基础建设出发,对我国水生实验生物的研究与发展的标准化、产业化、必要的资质认可及信息交流提出建议。 相似文献
40.
目的观察PM2.5混悬液染尘大鼠的肺组织病理学改变及银染色显示肺内尘粒的效果。方法将收集的游离PM2.5制成混悬液,72只Wistar大鼠随机分为低剂量组(每0.2ml含PM2.50.3nag)、中剂量组(每0.2ml含PM2.50.75mg)、高剂量组(每0.2ml含PM2.52mg)和对照组,每组18只。3个实验组分别以不同的剂量采用支气管肺内滴入方式染尘,每周染尘1次。分别于染尘后第4、12及24周时,取肺脏,石蜡包埋组织切片进行HE染色及沃森一斯塔理(Worthin-Starry,WS)银染色观察、透射电镜(TEM)观察,对肺内尘粒进行X-线质谱元素分析(X-RSA)。计数大鼠肺内肉芽肿样病变的数目,测定肺内尘粒的沉积程度、平均积分吸光度值(IOD)和平均积分面密度值(IAD)。结果随着染毒时间的延长和染毒剂量的增大,大鼠肺内肉芽肿样病变的数目及其细胞质内尘粒的IAD值和IOD值也逐渐增高。这些尘粒在WS染色切片上呈黑褐色,更清晰;其IOD值和IAD值均明显高于HE染色下的测定值,差异有统计学意义(P〈0.05);尘粒IOD值与肉芽肿病变数目呈正相关关系(r=0.639,P〈0.01)。TEM下大鼠肺内尘粒的超微结构与游离的PM2.5相同,X-RSA分析两者的主要元素成分也相同,均为硅元素。结论PM2.5混悬液染尘可以引起大鼠肺内出现肉芽肿样病变,WS银染色方法可以较好地显示被吞噬细胞吞噬后的PM2.5,其染色效果优于HE染色。 相似文献