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81.
Sunil Chandy M. N. Sadananda Adiga Girija Ramaswamy C. Ramachandra Lakshmi Krishnamoorthy 《Indian journal of clinical biochemistry : IJCB》2008,23(3):258-261
Folate and cobalamin (Vitamin B12) are two essential micronutrients involved in one-carbon metabolism, which affects heart disease, neural tube defects and
cancer. Methylenetetrahydrofolate reductase, the key enzyme involved in one carbon metabolism produces methyl tetrahydrofolate
from methylene tetrahydrofolate, which in turn donates methyl group to homocysteine to generate methionine. There exist two
common low function polymorphic variants of the methylenetetrahydrofolate reductase gene involving nucleotides 677 C→T and
1298 A→C, which are associated with hyperhomocysteinemia. These polymorphisms are also linked with increased risk for certain
cancers such as breast cancer and at the same time providing a protective effect on colorectal cancer. In this case control
study, we have evaluated levels of folic acid, vitamin B12 and homocysteine in patients with colorectal cancer. Folate and homocysteine levels did not differ significantly between
the two groups; however an increasing trend was noticed with increase in homocysteine levels. Vitamin B12 levels were increased in cases compared to control group. 相似文献
82.
Rani James K. Thriveni Girija Ramaswamy Lakshmi Krishnamoorthy Geetashree Mukherjee P. P. Vijayalaxmi Deshmane P. P. Bapsy 《Indian journal of clinical biochemistry : IJCB》2008,23(4):345-351
HER-2 is overexpressed in approximately 20–30% of invasive Breast Cancer. ECD of the HER-2 protein is frequently cleaved and
released into the circulation, where it can be detected by ELISA in up to 45% of patients with metastatic breast cancer. The
objective of our study was to compare the current methods for the detection of HER-2 protein. Tissue HER-2 levels were studied
in 100 breast cancer patients by IHC and compared with serum HER-2 levels by ELISA. IHC frequency was 29%. Serum HER-2 ECD
was positive in 42% of patients. A statistically significant correlation was observed. HER-2 detected by IHC correlates significantly
with serum HER-2 levels detected by ELISA. Thus, ELISA is a reliable and economical tool to assess the HER-2 status in tumors,
when breast tissue sample is not available. 相似文献
83.
SRB显色法用于抗癌药物敏感性试验的研究 总被引:13,自引:0,他引:13
采用SRB显色法对96孔培养板中短期培养的人大肠癌细胞株Colo205、人骨肉瘤细胞株OS732,人舌癌细胞株Tca8113经5-FU,顺铂,蟾酥等药物处理后的活性进行了研究。结果表明,SRB法对这些细胞株的体外抗癌药物敏感试验结果稳定,该法与其它细胞毒试验相比有一定优点,值得推广应用。 相似文献
84.
目的探讨银杏叶总黄酮对体外培养的人肝癌HepG2细胞凋亡的促进作用及其分子机理。方法采用TUNEL法检测银杏叶总黄酮对HepG2细胞凋亡的影响,提取Bcl-2基因的mRNA,以RT-PCR法研究银杏叶总黄酮对Bcl-2基因表达的影响。结果银杏叶总黄酮使人HepG2细胞凋亡指数增加(P〈0.01),且呈剂量依赖效应;Bcl-2基因mRNA水平随银杏叶总黄酮浓度升高而降低。结论银杏叶总黄酮可促进人HepG2细胞的凋亡过程,并使Bcl-2基因mRNA水平降低,从而起到抗肿瘤的治疗作用。 相似文献
85.
86.
目的:制作乳腺癌调强放疗计划时,采用分段逆向调强优化方法以达到更好的靶区剂量和保护肺、心脏等危及器官。方法:应用Eclipse8.6计划系统针对10例乳腺癌患者(肿瘤原发部位左右侧各5例)分别制定T1,T2模式调强放疗计划,处方剂量均为DT50Gy/25次。T1模式采用左乳300°、330°、0°、30°、60°、90°和120°方向射野,右乳60°、30°、0°、330°、300°、270°和240°方向射野,设置优化参数进行逆向优化和剂量运算。T2模式采用与T1模式相同的角度方向设野,第一段总剂量24Gy,分次剂量2Gy,分12次治疗,设置优化参数进行逆向优化和剂量运算;第二段总剂量26Gy,分次剂量2Gy,分13次照射,设置优化参数,采用"Base dose plan"功能选择基于第一段治疗计划以总量50Gy来逆向优化和剂量运算。将两段计划相加作为T2模式的治疗计划,通过剂量体积直方图比较两种模式下计划的靶体积和危及器官剂量分布。结果:T1、T2模式调强放疗计划的靶体积均满足临床剂量要求,对于左侧乳腺癌,适形指数分别为0.727±0.034、0.751±0.034(t=-6.20,P=0.003);对于右侧乳腺癌,适形指数分别为0.691±0.058、0.729±0.048(t=-5.39,P=0.006)。对左侧乳腺癌,T2模式的左肺V10(%)、左肺V20(%)、左肺V30(%)、全肺V10(%)、全肺V20(%)、全肺V30(%)和心脏V10(%)均大于T1模式,分别增大5.0%、2.7%、3.7%、4.6%、2.6%、3.8%和4.4%。对于右侧乳腺癌,无充分证据说明危及器官各指标有差别。结论:与T1模式相比,采用分段逆向调强优化方法能更好的优化靶区的剂量分布,但对左侧乳腺癌而言,会略微增加左肺、全肺和心脏剂量受量。 相似文献
87.
88.
Cynthia Jane A. V. Nerurkar F. R. Karjodkar 《Indian journal of clinical biochemistry : IJCB》2007,22(2):114-117
Oral Cancer is one of the five leading sites of cancer in Indian population. The circulating immune complexes were investigated
in 100 serum samples of 60 oral cancer patients having different grades of the disease and 40 patients with precancerous lesions
obtained from Nair Hospital Dental collage, Mumbai. The results obtained were compared with those of group of 40 healthy blood
donors. Elevated levels of Circulating Immune Complexes were observed in oral cancer patients and patients with oral precancerous
lesions. 92% positive samples were observed in well differentiated squamous cell carcinoma whereas 100% positive samples were
observed in both moderately and poorly differentiated squamous cell carcinoma. Oral leukoplakia and oral submucous fibrosis
showed 15% and 90% positivity respectively. Increased level of Circulating Immune complexes in high grade tumor suggest that
Circulating Immune complexes is likely to contribute in evaluating the degree of malignancy, but follow up study is needed
to draw any conclusion regarding it's prognostic role 相似文献
89.
Y. P. Singh O. P. Sachdeva S. K. Aggarwal K. Chugh Harbans Lal 《Indian journal of clinical biochemistry : IJCB》2008,23(3):290-292
Blood glutathione was estimated in fifty patients of head and neck cancer in the age group of 18–76 years and the results
were compared with a group of normal healthy controls. Mean blood glutathione level was found to be significantly lowered
in patients than the controls. Irrespective of the site, TNM classification, histopathology, and character of lesion, fall
in blood glutathione was nearly same in all the patients. The mean level was significantly increased after radiotherapy when
compared with the levels before radiotherapy. The decreased levels of GSH in-patients with head and neck cancer, observed
in the present study, may be due to its increased utilization by the cells. The results suggest that patients with head and
neck cancer have increased oxidative stress. 相似文献
90.
To clarify the possible mechanisms of α-anordin and probimane on calmodulin Ca++-Mg++ ATPase system, enzyme dynamic study was carried out by determining three dynamic parameters [the substrate concentration
(ATP)-response curve, dose (inhibitors)-response curve and time-response curve]. Our data have shown that the inhibitory rates
of α-anordrin and probimane are unrelated to substrate (APT) concentrations, but related to calmodulin concentrations. The
inhibition of α-anordrin and probimane is very quick that is completed within 1 to 5 min and can maintain more than 1 hr in
the same inhibitory rates. So it is possible that α-anordrin and probimane are calmodulin competitors with calmodulin-like
binding whose actions can occur by affecting the reaction balance of substrate and product on target enzymes of calmodulin
(Ca++-Mg++-ATPase). 相似文献