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91.
采用口服氯化铝建立小鼠学习记忆障碍模型,应用跳台法观察了纳络酮对铝(Al)中毒所致小鼠学习记忆障碍的改善作用,用火焰原子吸收分光光度法测定血锌(Zn)、铜(Cu)、锰(Mn)等含量.结果显示,氯化铝可导致小鼠学习记忆障碍,且有降低血Zn、Cu含量的作用(P<0.05);纳络酮治疗有改善Al中毒小鼠学习记忆障碍的作用,同时也增加了血Zn、Cu的含量. 相似文献
92.
选用43具青年尸体,蛛网膜下腔注入铸型造影剂,低温冷冻,以椎间盘为中心制作断层标本,同时选取40例正常健康人进行超声、CT及MR扫描图像分析.发现同组中不同椎间盘水平测量数据的大小不同;解剖学与影像学各测量结果进行比较无显著性差异. 相似文献
93.
笔者对吉林省8种优势种群吸血蠓的昼夜活动节律进行了观察.结果表明:华库蠓、孔库蠓、伊库蠓、原野库蠓、亚单带库蠓、淡角库蠓属于晨昏活动型蠓种;明边库蠓属于夜间活动型蠓种;浑江铗蠓属于白天活动型蠓种. 相似文献
94.
人参茎叶中二醇组皂甙对小鼠学习记忆及铜、锌、锰含量的影响 总被引:3,自引:0,他引:3
采用跳台法、火焰原子吸收分光光度计法分别研究了人参茎叶中二醇组皂甙(PDS)对小鼠学习记忆和全血铜(Cu)、锌(Zn)、锰(Mn)微量元素含量的影响. 结果表明,不同给药剂量各实验组小鼠跳台错误次数明显低于对照组(P<0.01),潜伏期明显延长(P<0.01);各实验组全血Cu含量均高于对照组(P<0.01),而Zn含量没有变化(P>0.05),Mn含量随给药剂量增加而增高,提示PDS具有提高小鼠学习记忆作用,可能与Cu、Mn含量增高有关. 相似文献
95.
When first introduced, the advanced breast biopsy instrumentation (ABBI® ) system seemed to have many advantages as a diagnostic procedure. Problems have arisen, however, both in terms of patient unsuitability and mechanical failure. In addition, there has been uncertainty as to whether the complete lesion removal it afforded could be considered definitive treatment in malignant cases. Incision margins were looked at to investigate that possibility. Of the 183 patients we saw in our first year of experience with ABBI, 48 (26%) were rejected for being poor candidates for it. In the remaining 132 biopsies there were 31 (23%) technical difficulties. All told, 14 malignancies were discovered, all of which appeared to have pathology-free incision margins radiologically. However, 13 of these 14 (93%) proved on pathologic examination to have residual malignancy. ▪ 相似文献
96.
97.
This paper describes the development of a self-report scale to assess the internal experience of humiliation. After defining the construct, an item pool of 149 items was generated, utilizing a five-point Likert scale response format. A sample of 253 individuals ages 15 to 51 (M= 20.66) was used to conduct the item trial. The item pool was evaluated through item and factor analyses. Factor analysis identified two correlated factors accounting for 58% of scale variability. The 20 items loading on factor one were labeled the Fear of Humiliation Subscale and the 12 items loading on factor two were labeled the Cumulative Humiliation Subscale. The full scale of 32 items is called the Humiliation Inventory. Reliability analyses indicate that the subscales and the full scale have high internal consistency. Exploratory analyses of mean scores across six demographic groups indicate significant differences between male and female mean scores on the total scale and the two subscales. 相似文献
98.
C W Mays R L Aamodt K G Inn D R Brown R R Greenberg V G Iyengar F J Schima L S Slaback J W Tracy T P Lynch 《Health physics》1992,63(1):33-40
Results of gamma-ray measurements of selected tissues from a patient who was injected with Thorotrast almost 36 y ago are reported. The purposes of this study were: 1) to determine the relative tissue distribution and activities of specific radionuclides in the 232Th decay chain, specifically 228Ra (as measured by 228Ac), 212Pb, and 224Ra (measured directly and as measured by 212Pb), and 2) to evaluate the level of radioactive disequilibrium among the daughter products. The spleen and liver had the highest concentrations of radioactivity. Bone also appears to be a long-term sink for 232Th daughter products based on estimates from a small portion of one rib. Larynx and esophagus contained measurable activity, which may have been due to their proximity to the "Thorotrastoma." Radioactivity in the remaining measured tissues were low, as expected. Secular equilibrium could be demonstrated in bone, pancreas, larynx, esophagus, and breast. Significant disequilibrium was observed for spleen, liver, kidney, and red blood cells. Radioactivity measurements reported here will be useful in estimating radiation doses to selected tissues. Such dose estimates are valuable in refining current risk estimates (e.g., liver) and in identifying tissues at risk for further epidemiologic studies. These results, while consistent with other published studies, should be interpreted with caution since measurements were made on only one patient. 相似文献
99.
William T. Roubal Tracy K. Collier Donald C. Malins 《Archives of environmental contamination and toxicology》1977,5(1):513-529
Carbon-14 labeled benzene, naphthalene, and anthracene were administered to young coho salmon (Oncorhynchus kisutch) in the food and by intraperitoneal injection. Regardless of the mode of application the accumulated carbon-14 (% administered dose) in key organs (e.g., liver and brain) increased in the order anthracene > naphthalene > benzene over various time periods. The metabolic fate of the hydrocarbons after intraperitoneal injection was studied. It was shown that the highest percentages of metabolites occurred in the gall bladder; however, significant amounts were also found in the liver, brain, flesh, and carcass. Solvent partition and thin-layer chromatographic techniques were developed to determine the structure of individual metabolites. In brain, liver, and gall bladder, 1-naphthol and 1-naphthyl glucuronic acid were major products of naphthalene metabolism; however, glycoside/sulfate fractions and mercapturic acid were indicated. The heart and flesh were rich in 1-naphthol and the former organ contained significant amounts of 1,2-dihydro-1,2-dihydroxynaphthalene. The findings indicated that the aromatic hydrocarbons in key organs increased in relation to the number of benzenoid rings. Further, it appears that aromatic metabolites are broadly distributed throughout fish exposed to polynuclear aromatic hydrocarbons. 相似文献
100.
目的观察人体于不同的头位倾斜条件下诱发的OCR反应特征,为建立其检测方法和实际应用提供依据.方法受试对象为地面人员22名和飞行人员11名,端坐于装有特制头托的座椅上,通过头位在冠状面内分别处于左右各倾斜30°、50°、70°的位置诱发静态OCR反应.采用红外视频眼动记录方法分别随机测定从头直位到左右各30°、50°、70°的眼动视频信号.最后以动头前即刻的眼球位置为零位,以眼球虹膜纹理为标志,对各时刻虹膜纹理与初始状态虹膜纹理进行互相关分析,找出相关度最大的一点为各时刻眼球位置,测量该时刻眼球与初始眼球位置的角度即为眼球扭转角度.结果头位倾斜引起的典型OCR反应曲线特征是,头位倾斜动作开始,首先引起一个幅度较大的与头动方向相反的眼球反方向旋转,随之,眼球反转角度逐渐减小,在头位倾斜到固定角度后,眼球反转角度在一定范围内波动或不变,未发现头位向同一方向倾斜不同角度引起的OCR有显著差异.飞行员与正常地面人群OCR反应未见显著差别.结论静态头位倾斜可以诱发出OCR反应,可用来评价耳石器功能. 相似文献