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排序方式: 共有4513条查询结果,搜索用时 15 毫秒
31.
冠心病中血糖与血清微量元素间的关系分析 总被引:1,自引:0,他引:1
对75例冠心病患者依血糖水平分两组,进行12种血清微量元素测定,旨在探讨微量元素与冠心病及糖尿病间的相互关系。结果发现锌、铬、锰、硒、钴元素高血糖组较对照组血清水平为低,呈非常显著差异(P<0.0l);铜、镍元素增高,差异显著(P<0.05);而锶、铁、砷、铅、铝元素两组间无显著差异(P>0.1)。表明部分微量元素与冠心病及血糖间存在着密切联系。 相似文献
32.
观察了5种常用螯合剂对大鼠体内微量元素排出量、组织分布的变化。结果表明,5种螯合剂可不同程度地增加机体必需微量元素Zn、Cu、Mg和Ca经尿液排出量。EDTA和DTPA的影响尤为明显。EDTA和DTPA可使Zn经尿液的排出量增加16-52倍,DTPA使肝脏Zn含量减少15.9%(P〈0.05),肝脏Cu含量下降60%(P〈0.05)。EDTA和DTPA注射后,肾中Zn含量明显增高,相当对照大鼠3. 相似文献
33.
The nonstructural protein 3 (NS3) of Dengue virus (DV) is a multifunctional enzyme carrying activities involved in viral RNA replication and capping: helicase, nucleoside 5'-triphosphatase (NTPase), and RNA 5'-triphosphatase (RTPase). Here, a 54-kDa C-terminal domain of NS3 (DeltaNS3) bearing all three activities was expressed as a recombinant protein. Structure-based sequence analysis in comparison with Hepatitis C virus (HCV) helicase indicates the presence of a HCV-helicase-like catalytic core domain in the N-terminal part of DeltaNS3, whereas the C-terminal part seems to be different. In this report, we show that the RTPase activity of DeltaNS3 is Mg2+-dependent as are both helicase and NTPase activities. Mutational analysis shows that the RTPase activity requires an intact NTPase/helicase Walker B motif in the helicase core, consistent with the fact that such motifs are involved in the coordination of Mg2+. The R513A substitution in the C-terminal domain of DeltaNS3 abrogates helicase activity and strongly diminishes RTPase activity, indicating that both activities are functionally coupled. DV RTPase seems to belong to a new class of Mg2+-dependent RTPases, which use the active center of the helicase/NTPase catalytic core in conjunction with elements in the C-terminal domain. 相似文献
34.
用于牙科复合树脂的具有固位力外形的无机填料的研究 总被引:6,自引:0,他引:6
本文介绍了一类微细的复合式无机填料。由于具有特殊的表面结构,这类填料与复合树脂中的树脂基质之间有良好的结合力,因此称之为“具有固位力外形的无机填料”。用此类填料配制的试验性复合树脂,不仅其磨耗性能有明显的改善,而且其它机械性能也有不同程度的提高。 相似文献
35.
In a series of three experiments, adult rats who suffered severe zinc deficiency and/or undernutrition during lactation were tested in a 17-arm radial maze for working memory, reference memory, forgetting and learning. In Experiment 1, eight out of 17 arms were baited. The zinc deficient (ZD) and undernourished (PF) rats revealed a learning deficit when compared to adequately nourished rats (AL). ZD rats also appeared to display a loss of working memory. No evidence of loss of reference memory was observed among any of the groups. A reverse learning procedure was used in Experiment 2 to test the same rats used in Experiment 1. ZD rats were significantly inferior in performance of the reverse learning task compared to the AL and PF rats. No significant differences in performance were noted between the AL and PF rats. Although all groups displayed forgetfulness from Experiment 1 to Experiment 2, no significant differences in forgetfulness were evidenced among the groups. In Experiment 3, all 17 arms were baited. The ZD rats displayed a significant working memory deficit as compared to the AL and PF rats. No significant differences in working memory between the AL and PF rats occurred. The possibility that the differences in performance were due to differences in food motivation or attention was considered and rejected. It was concluded that ZD rats experienced a severe learning deficit and some working memory deficit while the PF rats experienced a mild learning deficit as compared to the AL rats. 相似文献
36.
The effects of imidacloprid (Advantage) on sheep keds (Melophagus ovinus Linné 1758) were studied in vivo and in vitro by means of direct observation (monitored on video tape) and by light and electron
microscopy. It was found that:
1. Imidacloprid acted rapidly on all motile stages of the sheep keds. Within 3–4 min after exposure they became immobile and
their legs and the abdomen started tetanic trembling movements for 15–30 min, leading to death.
2. The compound is apparently taken up by the body, since it also acted on those sheep keds that had been exclusively exposed
to imidacloprid-contaminated filter papers.
3. The compound is available and active for more than 1 month in the wool of sheep; even rainfall does not reduce its efficacy.
Body contact between treated mother sheep and their lambs protects them from infestation with these ectoparasites.
4. The compound initiates an ultimately lethal destruction of the ganglia, nerve chords and related muscle fibers, as can
be seen in electron micrographs.
Received: 7 October 2000 / Accepted: 18 October 2000 相似文献
37.
目的 探讨中长跑有氧与无氧训练对血浆电解质及部分微量元素的影响 .方法 上海市及上海体院田径队中长跑运动员 ,根据个人运动专长 ,安排相应专项训练 ;12名进行有氧训练 ,14名进行无氧训练 ,分别在训练前及运动后即刻抽静脉血 ,检测血乳酸等电解质及微量元素铁、铜的水平 .结果 ①两组训练后 ,血乳酸、Na、Cl及无机磷(P)水平均显著升高 (p <0 .0 1) ;无氧组训练后 ,血清总钙 (Ca)及血清铁 (Fe)水平均显著升高 (p <0 .0 1) .②两组训练后 ,Cu水平显著下降 (p <0 .0 1,下降幅度均达 35 %以上 ) ;无氧组训练后 ,K水平有下降趋势 (p =0 .0 6 ) .③有氧组训练后 ,乳酸升高与K水平呈显著相关 ((r=- 0 .6 73,p <0 .0 5 ) ;无氧组训练后 ,乳酸升高与Mg水平显著相关 (r=0 .5 5 1,p<0 .0 5 ) ,与Na水平呈极显著相关 (r=0 .731,p <0 .0 1) .结论 ①有氧、无氧训练对电解质及微量元素水平的影响明显不同 .②无氧训练较有氧训练更需注意运动后电解质紊乱 ,尤需注意运动后血钙水平的升高及血钾水平的下降 . 相似文献
38.
猫阴部神经传入传出成分在脊髓内的定位分布—HRP逆行及跨越神经节追踪研究 总被引:1,自引:1,他引:1
向猫阴部神经及其分支注入HRP溶液,观察并分析了逆行和跨节追踪的结果。 1.证实阴部神经为含躯体传出、传入,内脏传出、传入纤维的混合神经,其内脏性传出、传入成分仅存在于阴茎背神经中。 2.逆行标记细胞出现于L_7—S_3前角Onuf核和S_(1-3)的中间带外侧核。本文结果表明,Onuf核是支配盆底横纹肌的运动核,但它和其它前角运动核在细胞形态和活性物质的分布上都明显不同。特别是它的一部分神经元的树突形成树突束到达中间带外侧核。本文结合排尿、排便功能从形态学上较详细地讨论了Onuf核和中间带外侧核的关系。 3.本文证明阴部神经领域的内脏初级传入(来自阴茎背神经)和躯体初级传入纤维都向骶髓后连合核区有浓密的投射。结合以往的工作讨论了盆腔脏器、外生殖器的内脏传入和坐骨神经、阴部神经的躯体传入在骶髓后连合核区汇聚的现象及机能意义,推测这种汇聚可能是产生牵涉痛和针刺镇痛机制的形态学基础。 相似文献
39.
[摘要] 目的:研究Iα1 hs1,2 VNTR多态性与我国IgA肾病的相关关系。 方法: 采集419例肾活检证实的IgA肾病患者及其一级亲属、条件相当的201例健康志愿者血样,提取基因组DNA。用PCR产物直接电泳法鉴定Iα1 hs1,2 VNTR基因型,采用以家庭为基础的传递/不平衡分析(TDT)和单倍型相对危险度(HRR),以及病例-对照研究分析Iα1 hs1,2 VNTR多态性与我国IgA肾病的相关关系。 结果: ① TDT分析结果显示Iα1 hs1,2 VNTR B等位基因从杂合子父母向患者传递的频率显著高于预期值(101 Trios, χ2=6.818, P<0.01,扩展TDT分析也得到相同结果(164家庭, χ2=7.583, P<0.01)。②与TDT结果一致,HRR分析同样显示Iα1 hs1,2 VNTR B等位基因的过度传递 (P<0.05, χ2=4.122, HRR=1.180), 而BB基因型具有更强的患病倾向 (P<0.05, χ2=4.411, OR=1.538)。③病例-对照研究显示IgA肾病组B 等位基因频率显著高于正常对照组(χ2=6.968, P<0.05)。 结论: Iα1 hs1,2 VNTR基因多态性与我国IgA肾病患者的易感性相关。 相似文献
40.
There were 26 male and female (nonpregnant and nonlactating) apparently healthy adult (5 to 10 years) field camels (Camelus dromedarius) studied to provide data regarding the normal values of trace elements in serum and different tissues. Blood samples were collected by jugular venepuncture and serum was separated by centrifugation. Tissue samples (liver, heart, striated muscle, spleen, kidney, and hair) were collected during postmortem examinations. All the samples were digested and analyzed for copper, iron, cobalt, and molybdenum using atomic absorption spectrophotometry. The results showed that the highest concentration of iron was present in the spleen and that the concentrations of this element in the liver and kidney were higher than those in the heart, striated muscle, serum, and hair (p<0.05). The lowest mean iron concentration was observed in the serum (p<0.05). The mean copper concentration was highest in liver in comparison to other tissues (p<0.05). No significant differences in cobalt concentrations were detected among different compartments. The mean molybdenum concentration of striated muscle, heart, kidney, spleen, and liver were significantly higher than those of serum and hair (p<0.05). No difference due to sex was detected in different tissue and serum concentrations of trace elements. 相似文献