结肠腺瘤与腺癌p53,c—erbB2蛋白及CEA的表达和意义

应用免疫组化法检测１５例正常结肠粘膜，４０例结肠瘤及４０例结肠癌组织的ｐ５３，ｃ－ｅｒｂＢ２和ＣＥＡ的表达。结果发现：结肠癌患者ｐ５３，ｃ－ｅｒｂＢ２及ＣＥＡ的阳性表达率均显著高于腺瘤（Ｐ〈０．０１）。ｐ５３阳性表达在不典型增生腺瘤患者中，重度显著高于轻度病例（Ｐ〈０．０１）；在结肠腺癌患者中低分化显著高于高分化病例（Ｐ〈０．０５）；ＣＥＡ的新型单克隆抗体ｃｏｌ－１对结肠癌的敏感性和特异性均高，阳     

C60的化学反应性和高分子化

综述了C_(60)化学研究的进展。C_(60)的化学反应性的研究展现了一个广阔的新领域,并使C_(60)作为一种新型的功能基团引入高分子成为现实。这些进展为进一步深入研究C_(60)尤其是C_(60)的材料化提供了前提。     

曲尼司特对豚鼠肺组织β肾上腺素受体向下调节的影响

用放射配体结合分析法分别测定了正常组、特布他林组、特布他林十曲尼司特组豚鼠的肺组织β受体最大结合力和解离常数,结果显示:给特布他林后豚鼠肺组织β受体发生明显的向下调节.曲尼司特可预防此向下调节的发生.     

细胞凋亡抑制因子（Fas／APO-1）与抗β2-肾上腺素能受体自身抗体的关系

目的 检测并比较心肌梗死急性期不同时间点，β2自身抗体阳性组与阴性组，患者血清中Fas／APO-1水平差异，了解β2自身抗体对Fas／APO-1的影响。方法 41例急性心肌梗死患者，分别于发病24h、7天、2～4周时取血，采用ELISA的方法，检测血清中β2自身抗体的阳性率以及Fas／APO-1的水平；另外取34位性别、年龄匹配的健康人的血同法检测Fas／APO-1作为对照。结果心肌梗死急性期Fas／APO-1的水平均高于对照组（P〈0．05），以梗死后24hFas／APO-1的水平为最高；心肌梗死急性期不同时间点，β2自身抗体阳性组Fas／APO-1的水平均高于阴性组，但两组的结果差异无显著性（P〉0．05）。结论 血清Fas／APO-1水平可以在一定程度上反映心肌细胞凋亡的变化趋势，β2自身抗体对Fas／APO-1的确切影响，有待更大规模的实验来证实。     

Transneuronal degeneration of thalamic neurons following deafferentation: quantitative studies using [3H]thymidine autoradiography.

Transneuronal degeneration of thalamic neurons following partial deafferentation was studied using [3H]thymidine autoradiography. Timed-pregnant female Sprague-Dawley rats received systemic injections of [3H]thymidine on embryonic day (E) 13, 14 and/or 15. On the day of birth, pups were anesthetized by hypothermia and subjected to unilateral enucleation, unilateral removal of the inferior colliculus or sham lesion. Animals were sacrificed on postnatal day 10 or 30 and the brains processed for autoradiography. Material from sham-lesioned animals demonstrates that neurons destined for the dorsal lateral geniculate nucleus (LGd) undergo final mitoses on E13, 14 and 15. Neurons in the ventral medial geniculate nucleus (MGv) undergo final mitoses on E13 and 14. Thirty days following neonatal unilateral eye removal, the contralateral LGd displays a loss of approximately 30-35% of [3H]thymidine labeled neurons. Neonatal unilateral removal of the inferior colliculus results in a loss of approximately 30-40% of labeled neurons in MGv. For both LGd and MGv, shorter survival times reveal less severe cell loss. Late generated (E15) LGd neurons show less severe loss following enucleation than do earlier generated neurons. These results document the degree of cell loss in sensory thalamic nuclei following deafferentation and demonstrate that [3H]thymidine autoradiography provides a useful quantitative method for assessing anterograde transneuronal cell loss in targeted populations of neurons in the developing central nervous system.     

Calcium, network activity, and the role of NMDA channels in synaptic plasticity in vitro.

Functionally effective neuronal circuits are constructed through a competitive process that requires patterned neuronal activity elicited by structured input from the environment. To explore the mechanisms of this activity-dependent synaptic restructuring, we have developed an in vitro preparation of mouse spinal cord neurons maintained in a 3-chambered cell-culture system. Sensory afferents that received chronic electrical stimulation for 3-5 d developed stronger synaptic connections than unstimulated afferents converging onto the same postsynaptic spinal cord neuron. Exposure to 100 microM DL-2-amino-5-phosphonovaleric acid (APV), an antagonist of the NMDA channel, during the stimulation period prevented the competitive advantage associated with electric stimulation. However, when APV was applied with a higher concentration of calcium (3 mM), activity-dependent synaptic plasticity was no longer inhibited by the NMDA receptor antagonist. This reversal of APV block of the plasticity was not impaired by reducing transmitter release with 3 mM magnesium (in addition to 3 mM calcium and APV). A suppressant effect of APV on spontaneous activity was observed, which was attributed to loss of the NMDA component of the EPSP. Activity-dependent plasticity was also blocked if spontaneous activity was suppressed with dilute tetrodotoxin (TTX; 5-10 nM), a dosage that reduces excitability of neurons but is insufficient to block sodium-dependent action potentials. These experiments bring into question how NMDA channel activation is involved in the processes of synaptic remodeling during development. The data suggest that postsynaptic activity is required for synaptic remodeling, but this activity need not involve NMDA receptor activation specifically for activity-evoked synaptic plasticity. Instead, the mechanism for plasticity appears to operate through calcium-dependent processes in general.     

胞嘧啶脱氨酶的原核表达和多克隆抗体的制备

目的：在原核系统中表达并纯化大肠杆菌胞嘧啶脱氨酶（cytosine deaminase,CD)，制备鼠抗大肠杆菌CD多克隆抗体，方法：亚克隆CD基因到原核表达载体pMAL-c2和pBV222中，并转化入大肠杆菌DH5α内，诱导表达并纯化MBP-CD和6his-CD融合蛋白，用纯化的MBP-CD融合蛋白免疫小鼠制备多克隆抗体。结果：通过重组质粒的酶切筛选出重组阳性克隆，成功地表达和纯化出MBP-CD和6his-CD融合蛋白，用纯化的MBP-CD成功制备了鼠抗CD多克隆抗体，并用6his-CD和GST-CD重组蛋白进行Western印迹分析，证实了抗体的正确性，结论：应用多克隆抗体可以检测体内外CD基因的表达，为临床前和临床上深入开展CD基因的生物治疗研究提供重要的实验材料。