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101.
This study examined the immunohistochemical expression of p53 in human oral premalignancies and squamous cell carcinomas (SCC), and analyzed the relationship between the expression of p53 and the degree of dysplasia. p53 staining was observed in 15 of the 27 oral premalignant lesions (56%), including mild dysplasia, and 7 of the 10 oral SCC (70%), but in none of the 10 hyperplastic oral lesions. With increasing degrees of dysplasia and the appearance of SCC, not only was there an increase in the percentage of cases demonstrating p53 staining, but also an increase in the staining intensity of the positive cells and expansion of these positive cells. The results suggest that mutation of p53 is an early event during oral cancer development and p53 protein may be used as an early adjunct marker for identification of those premalignant lesions with higher malignant potential. 相似文献
102.
Yang M Jiang X Blake D Zhang Z Macey M Newland A Morris C 《International journal of oncology》1993,3(1):99-104
We have compared the specific activities of Cu/Zn superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GSH-Px) in a vinblastine sensitive human T-lymphoblastic cell line (CCRF-CEM) and its multiple drug resistant (MDR) counterpart cell line (CEM/VLB100), which over-expresses P-glycoprotein (PGP). We have found that the specific activity Cu/Zn SOD was consistently 38% increased in CEM/VLB100 cells compared with CCRF-CEM cells. In contrast, the activities of CAT and GSH-Px were similar in the two cell lines. These results suggest that MDR in CEM/VLB100 is a complicated phenotype which not only involves a PGP mechanism, but also a SOD protection mechanism against drug-mediated O2.- cytotoxicity. 相似文献
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古代疫病流行的诸种因素初探 总被引:7,自引:1,他引:6
Zhang ZB 《Zhonghua yi shi za zhi (Beijing, China : 1980)》1990,20(1):28-35
107.
Two new taxane diterpenes, decinnamoyltaxagifine ( 3) and decinnanioyltaxagifine acetate ( 2), have been isolated from the leaves and stems of TAXUS CHINENSIS. Their structures were elucidated by spectroscopic methods. Their (13)C-NMR chemical shifts were assigned. 相似文献
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109.
Theoperativetraumaoftotalgastrectomyissevere,andcomplicationsfrequentlymet.Soconsideringthehazardofoperationandtheoccurrenceofpostoperativecomplications,oneusuallysubstitutespalliativesubtotalgastrecto myforit,whichleadstotheshorttermre lapseoftumorin… 相似文献
110.
The prevalence of NIDDM and IGT and related factors among residents in some areas of Hubei Province, China 总被引:2,自引:0,他引:2
Wang ZZ Huang XZ Tang SB Chen YM Chen LG Jin ZX Luan XJ Zhang JH 《Biomedical and environmental sciences : BES》2000,13(2):148-153
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