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71.
The molecular heterogeneity of serum alpha-fe- toprotein (AFP) in 36 patients was studied by lectin affinity-radioimmunoelectrophoresis. Two variants of AFP, concanavalin-A (Con-A) reactive and the Con-A nonreactive, were obtained. AFP in all 13 patients with hepatoma consisted of the two va- riants, but the Con-A reactive variant was the ma jor one. In 8 patients with benign liver disorder, however, only the Con-A reactive variant of AFP was detected. Over 50"70 0f AFP in 5 patients with yolk sac tumor was Con-A nonreactive. Thus, there were three different patterns of AFP variants. The clinical implications are discussed.  相似文献   
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Thrombomodulin (TM), an anticoagulant factor on endothelial cells, is known to be expressed in non-endothelial cells as well. In neoplastic cells of lung adenocarcinomas, TM is expressed but its correlation with growth potential has not been studied. As TM expression has a negative correlation with cell proliferation in lung squamous cell carcinomas, we examined its growth effect on lung adenocarcinoma cells of the A549 cell line by inhibiting TM expression with antisense oligodeoxynucleotides (ODN). In the antisense ODN transfected cells, the expression of TM mRNA was decreased to 49% at 12 h and 47% at 24 h, which was in accordance with TM expression at the protein level. By IdU (5-iodo-2'-deoxyuridine) incorporation assay, the growth of A549 cells was found to have decreased to 36% of the control level at 24 h post-transfection. The suppression of cell growth was maintained in a concentration-dependent manner for 48 h after transfection, when the expression of TM started to rebound. In the transfected cells, the G1 phase cell count was reduced to 60.7%, compared with 68.2% in the control transfectants. These results suggest that TM expression may play a suppressive role in the proliferation activity of A549 lung adenocarcinoma cells.  相似文献   
75.
Background: Heterogeneity of tumor cells and the tumor microenvironment (TME) is significantly associated with clinical outcomes and treatment responses in patients with urothelial carcinoma (UC). Comprehensive profiling of the cellular diversity and interactions between malignant cells and TME may clarify the mechanisms underlying UC progression and guide the development of novel therapies. This study aimed to extend our understanding of intra-tumoral heterogeneity and the immunosuppressive TME...  相似文献   
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针灸及中药离子导入治疗膝关节骨性关节炎的疗效观察   总被引:1,自引:0,他引:1  
目的 观察针灸及中药离子导入治疗膝关节骨性关节炎的疗效。方法 将128例膝关节骨性关节炎患分为针导组和对照组。针导组采用以忆部取穴为主远端配穴为辅,针刺加局部艾灸,配合中药离子导入的方法,共治疗72例;对照组采用辨证分型内服中药配合常规非特异性消谈镇痛西药的方法,共治疗56例。结果 针导组治愈率达73.61%,对照组治愈率达39.29%。针导组治愈率明显优于对照组(P<0.01)。结论 针灸加中药离子导入治疗膝关节骨性关节炎有较好疗效。从出现效果的时间及治疗后的副作用等方面考虑,比口服药物治疗膝关节骨性关节炎有明显优势。  相似文献   
78.
The epidemiological survey of prevalence of NIDDM (non-insulin dependent diabetes mellitus) and IGT(impaired glucose tolerance) was conducted among 9450 residents aged 25-70 in some areas of Hubei Province, China. The results show that NIDDM and IGT prevalences are 2.62% and 4.48%, respectively. There is no significant difference between male and female (P > 0.05). The NIDDM prevalence in cities is slightly higher than that in countryside, but the difference is not significant (P > 0.05). However, the IGT prevalence in city is significantly higher than that in countryside (P < 0.01). The prevalence of both NIDDM and IGT is increasing along with the age of the population. It is also significantly related to the family history of NIDDM, hypertension, and high body mass index (BMI). By using stepwise logistic regression to analyse the risk factors of NIDDM, age (OR = 1.86), BMI(OR = 2.69), family history (OR = 2.84) and hypertension (OR = 2.23) entered the model (significance level is alpha = 0.05).  相似文献   
79.
PF方案化放治疗晚期鼻咽癌的远期疗效   总被引:29,自引:0,他引:29  
Gu Z  Wei Q  Huang K 《中华肿瘤杂志》1997,19(5):392-394
目的探索用PDD/5-Fu方案化放治疗晚期鼻咽癌的疗效。方法1989年12月~1990年12月间,选择76例Ⅲ、Ⅳ期鼻咽癌患者,先作3周期PDD(20mg(m2)-1d-1,iv,第1~5天)和5-Fu[700mg(m2)-1d-1,连续静脉滴注,第1~5天]诱导化疗,随后尽快作放疗,此为综合治疗组。以1989年作单纯放疗的86例晚期鼻咽癌患者作对照组。两组放疗方法、时间/剂量分割均相同。结果化疗有效率为89.3%,完全缓解率为18.4%。综合治疗组(综合组)总的5年生存率为48.7%,对照组为33.7%(P>0.05)。综合组T2N3和T2~4N3患者的5年生存率为44.1%和39.5%,均明显高于对照组的21.6%及20.4%(P<0.05)。结论PF方案化放治疗提高了T2~4N3患者的5年生存率。  相似文献   
80.
Activation of specific oncogenes and inactivation of tumor suppressor genes play major roles in mechanisms leading to neoplastic transformation. The potential involvement of these genes in determining genome stability is an important issue. To examine the relationships between altered oncogene expression and the effects on genome stability, we have investigated the drug sensitivity properties of mouse 10T1/2 fibroblasts transfected with combinations of H-ras, c-myc and the proline 193 mutant form of p53. The relative colony forming efficiencies of these cells were investigated in the absence or presence of various concentrations of the chemotherapeutic agents, methotrexate, N-(phosphonacetyl)-L-aspartate (PALA) or hydroxyurea. The effects of altered oncogene expression were found to be drug and locus specific, and to lead to increased drug resistance (e.g. H-ras transfectants were significantly resistant to methotrexate or PALA), decreased drug resistance (e.g. H-ras/-myc transfectants were significantly less resistant to PALA or hydroxyurea than H-ras transfected cells), or to no significant change in drug sensitivity (e.g. H-ras transfected cells were not significantly different in sensitivity to hydroxyurea than non-transfected cells). Gene amplification was an important but not the only mechanism for drug resistance. Cells that were transfected with p53 (H-ras/p53 or H-ras/c-myc/p53) exhibited the greatest drug resistance properties with all three chemotherapeutic agents, in keeping with the important role of p53 in DNA repair and DNA amplification mechanisms. Although both H-ras/p53 and H-ras/c-myc/p53 groups exhibited very similar genome stability characteristics as determined by drug sensitivity results, they were significantly different in their abilities to produce transformed foci in vitro and lung metastases in vivo. The H-ras/c-myc/p53 transfected cells formed significantly higher numbers of transformed foci and exhibited a greater malignant potential. These results are consistent with observations that H-ras expression directly correlates with malignant potential, and that H-ras/c-myc/p53 transfected cells have higher H-ras expression than H-ras/p53 transfected cells. Alterations in genomic integrity through changes in onocogene expression play important roles in mechanisms determining drug sensitivity; in addition to genome destabilization, other events are critically involved in regulating transformed and malignant characteristics.  相似文献   
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