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31.
2-(1-Aryl-1-hydroxymethyl)- and 2-aroyl-DHAQ derivatives (DHAQ, 1,4-dihydroxy-9,10-anthraquinone), and 2-(1-aryl-1-hydroxymethyl)-ATO derivatives (ATO, anthracene-1,4,9,10-tetraone) were synthesized and their antitumor activities were determined. 2-(1-Aryl-1-hydroxymethyl)-DHAQ derivatives showed a stronger cytotoxicity compared to the series of 2-(1-hydroxyalkyl)-1,4-dihydroxy-9,10-anthraquinone derivatives. It was suggested that the presence of aryl group at the side chain accelerated the bioreductive activation leading to cell death. 2-Aroyl-DHAQ derivatives, despite their higher electrophilicity, revealed smaller cytotoxicity and antitumor activity (expressed by T/C value) than 2-(1-aryl-1-hydroxymethyl)-DHAQ derivatives. Thus, no consistent relationship between the electronic effect on aromatic side chain and the cytotoxicity was observed. ATO series exhibited a higher antitumor activity (T/C, 125 to approximately 218%), though their cytotoxicity was not further improved compared to that of 2-(1-aryl-1-hydroxymethyl)-1,4-dihydroxy-9,10-anthraquinones. They manifested no correlation between the cytotoxicity and the antitumor activity. In case of 2-[1-hydroxy-1-(4-propylphenyl)-methyl]-ATO, the most bioactive one in vivo among the same series, it showed an ED50 value of 10.2 mg/mL and a T/C value of 218%. It is assumed that the anthracene-1,4,9,10-tetraones after uptake into cellular tissues might be transformed to a cytotoxic metabolite(s). 相似文献
32.
Takahashi Y Mai M Wilson M Kitadai Y Bucana C Ellis L 《International journal of oncology》1996,8(4):701-705
To determine the role of site of tumor implantation on tumor angiogenesis, we implanted gastric cancer cells in the orthotopic (stomach) and ectopic (subcutaneous) locations in nude mice. Tumors in the stomach demonstrated greater vascularization, higher levels of vascular endothelial growth factor (VEGF) expression, and greater proliferation compared with tumors in the subcutaneous tissues. These data suggest that the relationships among the expression of VEGF, vascularization, and proliferation of human gastric cancer cells are regulated by the organ microenvironment. In addition, VEGF may provide a target for anti-angiogenic therapy for gastric cancers. 相似文献
33.
RELATIONSHIP BETWEEN CORNEAL DELLEN AND TEARFILM BREAKUP TIME 总被引:1,自引:0,他引:1
Guanghuan Mai Shaomei Yang Eye Hospital Zhangshan Ophthalmic Center Sun Yat-sen University of Medical Sciences Guangzhou China 《眼科学报》1991,7(1):43-46
The BUT of 51 strabismus patients were measured before and after operation. The average pre-op BUT was 28.75 seconds(10.96"-91.80"). The post-op BUT in all operated eyes were reduced significantly, no matter what procedures had been performed and whether dellen appeared or not(P<0.01). The BUT in the group complicated dellen reduced from 23.22"(pre-op) to 8.61"(post-op). The incidence of dellen was 22.54% in this study. The incidence of dellen after rectus resection procedure(47.75%) was much higher than that after rectus recession(5.13%)(P<0.01). This study showed that dellen was closelyre related to the BUT and occurred more often in the eyes on which resection procedure was performed. It is considered that excessive lacrimation and elevation of the bulbar conjunctiva near the limbus may disturb the stability of the precornea tearfilm and cause the tearfilm break up earlier. Local corneal dehydration and dellen formation may be caused by reduced BUT. The incidence of dellen after operation may be higher if the cornea was carefully observed. 相似文献
34.
目的 建立一种快速有效的分析方法 ,达到鉴定淫羊藿及人参复方产品中黄酮苷类及人参皂苷类成分 ,并测定各成分含量的目的 ,最终控制复方中淫羊藿及人参的比例。方法 通过反相液相色谱 ,对包括药典所收载的淫羊藿药材及其产品进行分析。淫羊藿中的主要黄酮苷类成分 ,以淫羊藿定A、淫羊藿定B、淫羊藿定C、淫羊藿苷为对照品 ;对主要的人参皂苷类成分 ,以人参皂苷Rg1 、Re、Rf、Rb1 、Rb2 、Rd为对照品。结果 在同一色谱条件下 ,对主要黄酮苷类及人参皂苷类成分均可同时测定且分离良好。结论 该方法适用于淫羊藿、人参及其复方产品中淫羊藿黄酮苷类、人参皂苷类成分的定性、定量分析 相似文献
35.
胃癌7号染色体长臂的杂合性缺失分析 总被引:2,自引:0,他引:2
目的:检测胃癌患者7号染色体长臂微卫星位点的杂合性缺失(loss of heterozygosity,LOH),以初步确定7号染色体长臂上与胃癌相关基因连锁最密切的微卫星多态位点及LOH的临床意义.方法:在70例原发性胃癌中应用多重PCR技术扩增覆盖整个7号染色体长臂的9个微卫星位点(平均遗传距离为10cm),聚丙烯酰胺凝胶电泳分离PCR产物,用GeneScan、Genotyper软件进行分析.结果:9个微卫星位点的LOH均可发生于原发性胃癌,总的LOH频率为34.3%(24/70),其中D7S486和D7S798位点的LOH频率较高,分别为24.0%(12/50)和19.2%(5/26);总的LOH频率随临床分期而显著增高(P=0.046),D7S486位点的LOH频率在淋巴结转移者显著高于无淋巴结转移者(P=0.015).结论:在7号染色体长臂D7S486和D7S798位点附近,可能存在与胃癌发展相关的抑癌基因. 相似文献
36.
Bin Zhang Andrei Ougolkov Kaname Yamashita Yutaka Takahashi Masayoshi Mai Toshinari Minamoto 《Clinical cancer research》2003,9(8):3073-3079
PURPOSE AND STUDY DESIGN: Recent studies have shown that beta-catenin translocated into the cell nucleus functions like an oncogene. Accumulating evidence suggests that activation of the beta-catenin oncogenic signaling cascade along with its twin, the K-ras cascade, may exert syngeneic or synergistic effects on tumor development and progression. In the study reported here, we analyzed oncogenic beta-catenin activation on the basis of its nuclear accumulation (NA) and compared the results with those of mutational activation of K-ras in 74 patients with colorectal cancer to determine whether the two oncogene-mediated signaling cascades interact. RESULTS: We found two distinct patterns of beta-catenin activation, i.e., diffuse NA in 20 cases (27%) and selective NA at the tumor invasion front (NAinv) in 19 cases (26%). The presence of the NAinv pattern was significantly correlated with advanced Dukes' stage tumor (P = 0.0005) and the presence of distant metastases (P = 0.0064). K-ras proto-oncogene was mutated in the tumors of 31 cases (42%). Activated beta-catenin or K-ras was detected in most (78%) colorectal cancers analyzed, although a weak inverse correlation was found between the activities of the two oncogenes in the tumors. Importantly, most (7 of 8) patients with tumor showing both K-ras activation and the NAinv pattern of beta-catenin activation were in Dukes' stage C at surgery, and half of them developed distant metastases to the liver and lungs. CONCLUSION: The results suggest that although oncogenic activation of beta-catenin and K-ras is independent in the process of clinical cancer development, combined analysis of the two major oncogenes can detect most colorectal cancers and identify a subset of patients with poorer outcomes. Consequently, activation of either or both of these oncogenes may serve as a genetic marker for molecular diagnosis. 相似文献
37.
AIMS: To study the effect of prone and supine sleep on infant behaviour, peripheral skin temperature, and cardiorespiratory parameters to aid understanding of why prone sleeping is associated with an increased risk of sudden infant death syndrome. METHODS: Of 33 enrolled infants, 32 were studied at 2.5 and 28 at 5 months of age. A computer aided multichannel system was used for polysomnographic recordings. Behaviour was charted separately. RESULTS: Prone REM (active) sleep was associated with lower frequencies of short arousals, body movements and sighs, and a shorter duration of apnoeas than supine REM sleep at both ages. At 2.5 months there were less frequent episodes of periodic breathing during prone sleep in non-REM (quiet) and REM sleep. Heart rate and peripheral skin temperature were higher in the prone position during both sleep states at both ages. CONCLUSIONS: The observation of decreased variation in behaviour and respiratory pattern, increased heart rate, and increased peripheral skin temperature during prone compared with supine sleep may indicate that young infants are less able to maintain adequate respiratory and metabolic homoeostasis during prone sleep. 相似文献
38.
Hidehiro Nomura Yutaka Takahashi Masayoshi Mai 《International journal of clinical oncology / Japan Society of Clinical Oncology》1998,3(2):117-120
A 53-year-old woman had shown repeated, partial responses to chemotherapy for large, multiple liver metastases of sigmoid
colon cancer. After a partial response to 5-fluorouracil plus leucovorin therapy, an 89.7% reduction of the 5-fluorouracil-resistant
metastatic tumor was achieved by giving CPT-11 (irinotecan) at a dose of 100 mg/body per week. We suggest that CPT-11 should
be recommended as an effective second-line treatment for unresectable liver metastases of colon cancer, after 5-fluorouracil-based
chemotherapy. 相似文献
39.
湖南省学生生长发育长期变化趋势分析 总被引:7,自引:2,他引:7
目的了解湖南省儿童青少年生长发育长期变化趋势,为开展学校卫生保健工作提供资料.方法分析2000年湖南省7~22岁学生体质调研资料,并与1985年进行比较.结果城市男女生、农村男女生身高分别平均增长了2.9 cm,2.4 cm,2.3 cm和1.5 cm,体重分别平均增长了4.7 kg,2.6 kg,1.8 kg和0.6 kg.城市男女学生胸围分别平均增长了1.1 cm和2.6 cm,农村男生胸围平均减少0.9 cm,农村7~9岁女生胸围下降明显.城乡各年龄组男女学生肺活量指数均显著下降(P<0.01).农村学生形态指标发育高峰年龄明显提前.结论湖南省学生身高、体重发育呈现出长期增长趋势,其增长值小于同期全国平均水平.应加强学生体育锻炼,注意改善农村学生营养,青春期卫生教育应始于小学高年级. 相似文献
40.