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981.
982.
研究急性非淋巴细胞白血病细胞中原癌基因c-myc的表达及临床意义。方法采用蛋白质免疫印渍和单克隆抗体免疫细胞化学染色方法检测30例ANLL细胞中原癌基因c-myc的表达。结果19例表达阳性,阳性率为63%。ANLL中白血病细胞的阳性细胞百分率为29%-96%,c-myc在不同病人的白血病细胞中表达水平不一样;c-myc的表达和患者骨髓中白血病细胞百分率显著相关,和患者年龄,性别,外周血白细胞计数。  相似文献   
983.
分别用我国常见的15群15型钧端螺旋体多克隆抗体对我国常见的15群15型钧端螺旋体全菌蛋白进行了Western blotting分析。结果显示:用不同群的多克隆抗体与15群15型钩端螺旋体参考株的全菌蛋白反应,其图谱并不相同,表现在阳性反应带数量的多少和分子量的变化;而用同一群多克隆抗体与15群15型钩端螺旋体参考株的全菌蛋白反应,其Western blotting图谱非常相似,都有3条分子量分别为25×10~3、32×10~3和34×10~3上下的主要蛋白反应带和3~4条次要蛋白反应带,但其图谱并不完全相同,主要表现在不同群间1条主要蛋白的分子量在25×10~3上下变动,证实主要蛋白质可将不同群型钩端螺旋体进行区分;25×10~3,32×10~3和34×10~3蛋白质是所有15群15型钧端螺旋体参考株的主要外膜蛋白和抗原成分。这一研究结果对我国常见钩端螺旋体的分类和鉴定,诊断试剂盒、亚单位菌苗和基因工程菌苗的研制有重要意义。  相似文献   
984.
接触高温,CO工人血浆中的HSPs抗体水平   总被引:3,自引:0,他引:3  
应用WesternBlot方法,利用已纯化的HSPs抗原,检测了接触高温、CO工人血浆中HSP27、HSP60、HSP70、HSC70、HSP89α和HSP89β抗体水平。结果发现:工人血浆中HSP27、HSP70抗体阳性检出率以有CO接触职业史者最高,有高温接触史者次之,无两者接触者最低;HSP60抗体仅在有CO、高温接触史人群中出现;HSC70在3组间无差异;HSP89α、HSP89β在3组人群中均未检出。HSPs抗体阳性或阴性者与吸烟、饮酒和既往病史等方面无明显关系,但与职业接触史有关。  相似文献   
985.
本研究以α—~(32)P—dCTP标记的c—myc,c—fos和c—Ha—ras癌基因为探针,应用限制性内切酶技术和Southern印迹杂交方法对15例人乳头瘤病毒16型(HPV—16)基因组已发生整合的宫颈癌标本中上述三种癌基因进行了分析。结果表明,在含有HPV—16基因组整合的大多数宫颈癌组织(10/15)中,细胞myc(c—myc)原癌基因表现出不同程度的扩增或(和)重排,个别宫颈癌组织同时存在着c—ras原癌基因的重排,而HPV—16阳性但未发生整合的2例正常宫颈组织中(亚临床乳头瘤病毒感染)无类似的分子改变,提示c—myc原癌基因的扩增或(和)重排可能与HPV—16的整合有关,并协同参与致癌过程。  相似文献   
986.
Epstein-Barr virus (EBV) is known to be associated with two malignant diseases, nasopharyngeal carcinoma (NPC) and endemic Burkitt's lymphoma. In this study, the genomes of EBV in biopsy specimens from 4 NFC patients in Japan were analyzed using Southern blot hybridization. The NPC tissues of all examined cases contained rearranged EBV genomes whose Bam HI H fragments were larger than those of prototype EBV genomes. One of them had a Bam HI fragment containing contiguous sequences of Bam HI Y and H. A single-sized EBV DNA terminus was observed in these NPC tissues, implying the evolution of the carcinoma from a single EBV-infected cell.  相似文献   
987.
A rapid, flexible method based on ion-pair reversed-phase high-performance liquid chromatography is described for the separation and quantitation of frusemide and its principal hydrolysis product, saluamine, in the presence of potential contaminants, photolytic products and other degradants. The method is stability-indicating and has been shown to be applicable to the determination of frusemide and saluamine in injectable forms of frusemide. Response was linear both for frusemide (0?50 jug/ml; r = 0.9999) and saluamine (0?10 μg/ml; r = 1.0000). The on-column sensitivity of the assay was 1.3 ng frusemide and 1.1 ng saluamine. The method was applied to intravenous admixtures of frusemide and in studies on the effect of heat and/or light stress on other intravenous dosage forms. The saluamine assay was found to be sufficiently sensitive to monitor low levels of degradation of frusemide in the absence of photolytic degradation.When frusemide injection was transferred to a polypropylene syringe for slow intravenous injection and stored at room temperature unprotected from light for 24 h, the level of frusemide degradation, as indicated by saluamine, remained at 0.2%, which was within the 1% compendial limit of saluamine in frusemide. When used as an additive in Compound Sodium Lactate Injection BP (Hartmann's Solution) or Sodium Chloride Injection BP 0.9% w/v, frusemide injection was stable for 24 h without protection from light. An autoclaved infusion of frusemide was stable for 10 weeks at room temperature when protected from light. A preliminary investigation of photolytic degradation of frusemide indicated a fall in pH of 3 units, precipitation and the presence of a number of uncharacterized photolytic degradation products. A number of impurities were detected in Saluamine BP Chemical Reference Substance.  相似文献   
988.
Nine cases of intracranial hemorrhages related to cocaine usage are presented. Another 5 cases from the literature are reviewed. The relationship between severe cocaine-induced hypertension, and the development of subarachnoid or intracerebral hemorrhages is noted, and apparently is related to sudden transient increases of blood pressure related to cocaine use.  相似文献   
989.
One hundred and thirty children with superficial atypical mycobacterial lymphadenitis have been treated between 1958 and 1974. The introduction of Double Mantoux testing has provided a reliable means of differentiating human and bovine from atypical infection and has enabled us to cease the routine use of antituberculous drugs. Adequate local surgical excision has become the treatment of choice.  相似文献   
990.
Li SX  Cui N  Zhang CL  Zhao XL  Yu SF  Xie KQ 《Toxicology》2006,217(1):46-53
Occupational exposure and experimental intoxication with acrylamide (ACR) produce a neuropathy characterized by nerve degeneration. We hypothesize that ACR differentially affects the expression of bcl-2, bax and caspase-3 in the central nervous system (CNS) and the peripheral nervous system (PNS) tissue. Male adult Wistar rats were given ACR (20, 40 mg/kg i.p. 3 days/week) for 8 weeks. Samples of the cerebral cortex, cerebellum, spinal cord and sciatic nerves were collected and examined for bcl-2, bax and caspase-3 expression using Western blotting. Subchronic exposure to ACR reduced cortical bcl-2 expression in the low dose, increased it in the high dose; the change of bcl-2 expression in the spinal cord and cerebellum followed the same pattern as that described in the cerebral cortex; there was no significant change in the expression of bax in the cerebral cortex and the spinal cord, however, in the cerebellum the change of bax expression and bcl-2 expression is just the reverse. Thus, the bcl-2/bax ratio of the CNS tissue was affected by exposure to ACR, it decreased in the low dose group and increased in the high group. Compared to control, densitometric analysis showed that in the sciatic nerves the expression of bcl-2 and bax expression was markedly increased following ACR administration. The expression of inactive isoforms (32 kDa) of caspase-3 was not altered in the cortices of ACR-treated rats, but increased in their spinal cords and sciatic nerves. Thus, subchronic exposure to ACR affected the expression of death-related proteins in the CNS and PNS tissue, which indicate there is the early molecular regulatory mechanism of apoptosis in the neuropathy induced by ACR.  相似文献   
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