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91.
Effects of Aging and Advanced Glycation on Gene Expression in Cerebrum and Spleen of Mice^1 总被引:4,自引:0,他引:4
Liang YX Wang Z Li DD Jiang JM Shao RG 《Biomedical and environmental sciences : BES》2003,16(4):323-332
Objective To analyze the effects of aging or advanced glycation on gene expression in the cerebrum and spleen of female C57BL/6J mice. Methods The gene expression profile wasdetermined by using cDNA expression arrays containing 588 cDNA. 相似文献
92.
93.
目的 探讨癌基因 c- raf- 1的反义寡核苷酸对人卵巢癌细胞放射敏感性的影响。方法 设立 c- raf- 1正义寡核苷酸组和非处理组 (仅加入等量的脂质体 )作对照 ,用 RT- PCR检测卵巢癌细胞处理前后 c- raf- 1表达水平的变化。用平板克隆形成试验检测人卵巢癌细胞株 SKOV3在脂质体 - c- raf- 1反义寡核苷酸作用前后受 6 0 Coγ射线不同剂量照射后的集落形成率。结果 c- raf- 1反义寡核苷酸能抑制 c- raf- 1癌基因的表达 ,经脂质体介导的 c- raf- 1反义寡核苷酸作用的卵巢癌细胞经γ射线照射后其集落形成率较转染正义寡核苷酸组及单纯照射组明显下降 (P<0 .0 1) ,而转染 c- raf- 1正义寡核苷酸组的集落形成率与单纯照射组相比无明显差异 (P>0 .0 5 )。结论 c- raf- 1反义寡核苷酸通过抑制 c- raf- 1的表达降低人卵巢癌细胞株 SKOV 3放射抗拒性。该作用可能与 c- raf- 1反义寡核苷酸抑制了引起细胞辐射抗拒的细胞信号转导途径有关 相似文献
94.
95.
胆红素对神经突触膜Na^+,K^+—ATP酶影响的实验研究 总被引:20,自引:0,他引:20
为了研究胆红素的神经毒性作用,对59只出生2天的SD大白鼠分别予以腹腔注射不同剂量胆红素制造高胆红素血症动物模型,不连续密度梯度法分离提取脑神经元突触膜,测定Na+,K+-ATP酶活力。结果:随着血清胆红素浓度的逐渐增加,脑组织中胆红素沉积量也逐渐增加,神经元突触膜Na+,K+-ATP酶活力逐渐降低,Na+,K+-ATP酶活力与脑组织中沉积的胆红素量呈负相关(r=-0.34,P<0.01)。提示:胆红素对Na+,K+-ATP酶具有抑制作用。 相似文献
96.
以脉冲角加速度刺激在豚鼠记录出短潜伏期诱发反应,反应由发生于刺激开始后10ms以内的5~7个波组成,高强度刺激时反应振幅数微伏,I波潜伏期约2.5ms,不同动物及同一动物不同时间测试反应非常稳定。系列实验结果表明脉冲角加速度刺激诱发的豚鼠短潜伏期诱发反应系前庭诱发电位。 相似文献
97.
Propofol (Diprivan(TM); AstraZeneca, Wilmington, DE) is a commonly used drug for the induction of general anesthesia in the ambulatory setting. With the availability of a new bisulfite-containing generic formulation of propofol, questions have arisen regarding its cost effectiveness and safety compared with Diprivan(TM). Two hundred healthy outpatients were randomly assigned, according to a double-blinded protocol, to receive either Diprivan(TM) or bisulfite-containing propofol 1.5 mg/kg IV as part of a standardized induction sequence. Maintenance of anesthesia consisted of either desflurane (4%-8% end-tidal) or sevoflurane (1%-2% end-tidal) in combination with a remifentanil infusion (0.125 microg x kg(-1) x min(-1) IV). Patient assessments included pain on injection, induction time, hemodynamic and bispectral electroencephalographic changes during induction, emergence time, and incidence of postoperative nausea and vomiting. The two propofol groups were comparable demographically, and the induction times and bispectral index values during the induction were also similar. However, the bisulfite-containing formulation was associated with less severe pain on injection (5% vs 11%), with fewer patients recalling pain on injection after surgery (38% vs. 51%, P<0.05). None of the patients manifested allergic-type reactions after the induction of anesthesia. The acquisition cost (average wholesale price in US dollars) of a 20-mL ampoule of Diprivan(TM) was $15 compared with $13 for the bisulfite-containing propofol formulation. Therefore, we concluded that the bisulfite-containing formulation of propofol is a cost-effective alternative to Diprivan(TM) for the induction of outpatient anesthesia. Implications: Bisulfite-containing propofol and Diprivan(TM) (AstraZeneca, Wilmington, DE) were similar with respect to their induction characteristics; however, the generic formulation was associated with a smaller incidence of injection pain. Assuming that the drug costs are similar, these data suggest that the bisulfite-containing formulation of propofol is a cost-effective alternative to Diprivan(TM). 相似文献
98.
von Heijne M Hao JX Sollevi A Xu XJ Wiesenfeld-Hallin Z 《Acta anaesthesiologica Scandinavica》2000,44(6):665-671
BACKGROUND: There is often no satisfactory treatment for chronic pain after spinal cord injury. We have previously reported that intrathecal (i.t.) administration of the adenosine A1-receptor agonist R-phenylisopropyl-adenosine (R-PIA) or the opioid morphine has anti-allodynic effects in a model of presumed chronic central pain after photochemically induced spinal cord injury in rats. In the present study, we set out to investigate the possible interaction between i.t. R-PIA and morphine in spinally injured rats. METHODS: Sprague-Dawley rats displaying allodynia-like behaviors to mechanical and cold stimuli after photochemically induced spinal cord injury with minor motor deficits were used. R-PIA and morphine, either alone or in combination, were administered i.t. through an implanted catheter to lumbar spinal cord. RESULTS: Cumulative doses of R-PIA or morphine dose-dependently reduced the mechanical allodynia-like behavior, with a threshold of 1 nmol and 1.5 nmol, respectively. When co-administrated, R-PIA and morphine produced marked suppression of mechanical allodynia at doses of 5 pmol and 7.5 pmol, respectively. The effect of i.t. co-administration of R-PIA and morphine on cold allodynia was comparable to i.t. R-PIA alone. The combination of R-PIA and morphine did not increase adverse effects such as motor deficits in comparison to either drug alone. CONCLUSION: These results demonstrate a supra-additive interaction between the adenosine A1-receptor agonist R-PIA and morphine to reduce mechanical allodynia-like behavior in rats with chronic spinal cord injury. The combination of R-PIA and morphine administered spinally may be superior to R-PIA or morphine alone for treating such pain. 相似文献
99.
目的 探讨新西兰大白兔蜗神经直接动作电位 (directcochlearnerveactionpotential,DCNAP)的记录方法和特征 ,建立术中听觉监护动物模型。方法 纯种新西兰大白兔 6只 (12耳 ) ,乙状窦后进路暴露小脑、脑干及双侧桥脑小脑角区 ,插入针状电极于蜗神经 ,记录DCNAP ,并按常规方法记录听性脑干反应 (auditorybrainstemresponse ,ABR)。结果 用本方法记录的DCNAP具有振幅大、波形稳定、重复性好、记录时间短的特点 ,但个体差异较大。结论 在蜗神经桥脑小脑角区用针状电极可以可靠记录到DCNAP ,是术中听觉监护的可行方法 相似文献
100.
螺旋CT三维重建在鼻骨骨折中的临床应用价值 总被引:9,自引:0,他引:9
目的:探讨螺旋CT三维成像对鼻骨骨折的诊断价值。方法:应用GE Lightspeed Plus多排螺旋机扫描仪,对46例鼻外伤患者进行鼻骨横断面扫描和三维重建成像,并对检查结果进行分析。结果:46例鼻外伤患者中,9例普通X线侧位平片未发现骨折(19.6%);CT图像均能清晰显示骨折线,其中单纯鼻骨骨折32例(69.6%),并发上颌骨额突骨折11例(23.9%),上颌窦骨折1例,筛窦纸样板骨折3例,鼻中隔断裂1例。结论:螺旋CT三维成像对于诊断鼻骨骨折具有重要的诊断价值。 相似文献