大鼠脊髓损伤后DNA损伤与P53蛋白的表达

目的：检测大鼠脊髓损伤后神经细胞的ＤＮＡ损伤、凋亡及Ｐ５３蛋白的表达。方法：采用大鼠脊髓急性压迫损伤模型，应用原位末端标记、ＤＮＡ凝胶电泳、免疫组化等方法，对大鼠损伤脊髓进行检测。结果：脊髓损伤后４ｈ开始出现凋亡细胞及Ｐ５３蛋白表达，并在２４ｈ达到高峰。两者阳性细胞形态及分布有相似之处。ＤＮＡ电泳可见２４ｈ组出现特征性条带。结论：大鼠脊髓损伤后出现大量的ＤＮＡ损伤和神经细胞凋亡。Ｐ５３蛋白可能参与了诱导神经细胞凋亡的过程     

A组溶血性链球菌抗DNA酶B抗体检测的临床应用价值探讨

应用微量法检测抗DNA酶B ,以探索其在A组溶血性链球菌感染所致疾病中的临床应用价值 ,同时用乳胶凝集法检测抗链球菌溶血素O (ASO)。结果显示 :风心组、急性肾小球肾炎组抗DNA酶B阳性率分别为 86 .5 %和 90 .7% ,显著高于ASO阳性率 5 1.9%、5 5 .8% (P <0 .0 5 )。而两者联合检测阳性率在 90 %以上。风湿热组、咽炎扁桃体炎组抗DNA酶B阳性率分别为 73 .5 %和 2 8.8% ,虽和ASO (6 7.6 % ,38.5 % )差异无显著性 (P >0 .0 5 ) ,但两者联合检测阳性率可达88.2 %和 5 7.7%。提示抗DNA酶B对急性肾小球肾炎、风湿热、风心病的诊断有重要的临床价值。ASO联合抗DNA酶B检测可提高A组溶血性链球菌的检出率 ,两者有重要的互补作用     

K562细胞DNA聚合酶α—DNA引物酶复合物的纯化

用磷酸纤维素、DEAE纤维素、单链DNA纤维素和AMP-Sepharcse的顺序柱层析法从人慢性骨髓细胞性白血病K562细胞中纯化了DNA聚酶α与DNA引物酶的复合物。纯化过程经多次重复,结果稳定。DNA聚合酶纯化了117倍,DNA引物酶纯化了4583倍。共纯度足以满足研究化疗药物对这两种酶的抑制作用的需要。     

三种方法测定蚯蚓脱氧核糖核酸酶（EWD2）的分子量

目的用不同方法测定蚯蚓组织中一种新型脱氧核糖核酸酶分子量。方法采用凝胶过滤层析法、SDS-PAGE法和基质辅助激光解吸附电离飞行时间质谱法(MALDI-TOF)三种方法测定一种新型蚯蚓脱氧核糖核酸酶(EWD2)的分子量。结果凝胶过滤层析法、SDS-PAGE法和质谱法测定其分子量分别为62.16kD、62.08kD和69.075kD。结论EWD2为单亚基脱氧核糖核酸酶,其分子量在60-70kD。     

EB 病毒 DNA 酶基因特异性结合蛋白的检测

ＰＣＲ法扩增出ＥＢ病毒ＤＮＡ酶全基因之后，用［γ－３２Ｐ］ＡＴＰ进行５’末端标记，然后利用凝胶迁移分析法（ｇｅｌｍｏｂｉｌｉｔｙｓｈｉｆｔａｓｓａｙ）来检测与该基因结合的蛋白质。结果表明在Ｒａｊｉ细胞核和细胞浆中均有ＥＢ病毒ＤＮＡ酶基因非特异性和特异性结合蛋白，在人乳清中也有与该基因结合的蛋白质。     

重组EB病毒DNA酶的生物学特性及其应用的初步研究

经温度诱导含正向目的基因工程菌粗提液的ＤＮＡ酶活性比宿主菌本身的ＤＮＡ酶活性高７倍以上，且比等蛋白含量激发的Ｒａｊｉ细胞粗提液ＤＮＡ酶活性高２倍以上；阳性血清对重组ＥＢ病毒（ＥＢＶ）ＤＮＡ酶的中和率高达８３．５％；用重组酶粗提液和Ｒａｊｉ细胞ＤＮＡ酶检测的１０６例鼻咽癌（ＮＰＣ）病人血清抗ＥＢＶＤＮＡ酶抗体（ＥＤＡｂ）水平，结果无显著性差异，检出鼻咽癌的效率亦无显著性差异；表明重组酶经进一步提纯并标准化定量后可用于临床常规检测及大规模普查。     

Anti-streptococcal antibodies in the diagnosis of acute and post-streptococcal disease: streptokinase versus streptolysin O and deoxyribonuclease B

AIMS: To establish population normal values and compare the diagnostic value of antibodies against streptokinase (ASK), streptolysin O (ASO) and deoxyribonuclease B (ADNaseB) singularly and in combinations in acute and post-streptococcal disease. METHODS: A retrospective analysis of serological results was performed to define population norms. Subjects with acute culture-confirmed infection and post-streptococcal disease were assessed using population norms, as were matched controls. The sensitivity and specificity of each antibody assay and of combinations of the different assays were calculated. RESULTS: Age specific population normal values were derived from 2,321 specimens. None of the three antibodies alone or in combination was a reliable marker of acute streptococcal infection. The sensitivity and specificity of a single antibody titre in post-streptococcal disease ranged from 70.5 to 72.7% and 86.4 to 93.2%, respectively. The combination of ASO and ADNaseB was the most sensitive and specific combination for identifying post-streptococcal disease (sensitivity 95.5%, specificity 88.6%). CONCLUSIONS: In the diagnosis of acute and post-streptococcal disease, the addition of ASK does not increase the sensitivity or specificity of serological testing. A combination of ASO and ADNaseB is required in post-streptococcal disease to achieve maximum sensitivity and specificity.     

Apoptosis and P53 protein expression after rat spinal cord injury

AworkshopwasorganizedbytheNationalIn-stituteofNeurologicaDisordersandStrokeinSeptember1995.TheobjectiveofthisworkshopwastopromoteinquiryandtofosterapplicationofresearchinDNAdamageandrepairaftercentralnervoussystem(CNS)injury['].Nowinvestiga-torshavefoundthereareextensiveDNAdamageinmodelsoffocalcerebralischemiaandtraumaticbrain,withneuronsapoptosis.DNAfragmenta-tioncorrelatedgenes(hsp,IEGs,bcl-2,bax.p53)expression["']'Buttherehavebeenonlyfewstud-iesonDNAdamageandcorrelativegenesexpres…     

赤子爱胜蚓DNase活性测定方法

目的　研究赤子爱胜蚓 -地龙组织提取物DNase活性测定方法。方法　应用单相酶扩散法和紫外吸收法分别对其酶解底物DNA测定。结果和结论　两种方法同时应用可扩大其测定酶活力范围 ,且两方法的数据结果间存在稳定的函数关系 ,为赤子爱胜蚓DNase以及其他DNase的活力测定提供了可行的实验方法。