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991.
Summary To study the effects of family history and reproductive, anthropometric, and dietary factors on the risk of breast cancer among low risk populations, we conducted a hospital-based case-control study involving 908 patients with breast cancer and their matched controls, in Japan. A positive family history of breast cancer significantly increased the risk of breast cancer (odds ratio = 1.52, 95% confidence interval: 1.14–2.03). The risk further increased with increasing number of family members affected. Obesity, single marital status, fewer births, a late childbirth, and less consumption of green-yellow vegetables and dairy products were also associated with an increased risk of breast cancer. These associations were independent in multivariate analyses. There was no increase in risk associated with consumption of high fat foods. When analyzed by menopausal status, the association with family history of breast cancer, especially in the first degree of relatives, was more evident for premenopausal breast cancer. The associations with obesity and lower consumption of dairy products were more pronounced for postmenopausal breast cancer, while those with lower parity and single marital status were stronger for premenopausal breast cancer.  相似文献   
992.
Summary Female BDF1 mice inoculated with MXT (3.2) estrogen independent mouse mammary carcinoma were treated for three weeks with microcapsules of the luteinizing hormone-releasing hormone (LH-RH) agonist [D-Trp6]LH-RH, the antagonist SB-75, the somatostatin analog RC-160, or combinations. The lack of estrogen dependence of the tumor was proved by bilateral surgical ovariectomy, which had no effect. In two experiments, treatment with 25µg/day doses of each analog alone resulted in a significant inhibition of tumor growth as shown by a 40–53% inhibition of tumor volumes, 38–43% decrease in tumor weights, and histological signs of tumor regression. However, the combination of SB-75 or [D-Trp6]LH-RH with somatostatin analog RC-160 caused greater reduction of tumor volume (68 and 61%) or tumor weights (59 and 56%), than single analogs, and histologically the occurrence of apoptosis and decrease in AgNOR numbers was more pronounced in the groups receiving combination therapy. Specific binding sites for [D-Trp6]LH-RH, EGF, and IGF-I were demonstrated in the tumor membranes. The binding capacity of LH-RH receptors was decreased by treatment with the analogs, the greatest down-regulation being caused by combination therapy. A significant decrease in EGF binding capacity was observed after treatment with the LH-RH analogs, alone or especially in combination with somatostatin analog RC-160. The combination of these analogs also caused a reduction in IGF-I receptors. The finding that LH-RH agonists and antagonists and somatostatin analogs inhibit the growth of estrogen independent mammary tumors, and that combinations are more effective than single analogs, might be of practical importance in human breast cancer therapy.  相似文献   
993.
A stable cell line, KHM-3S, was established from a patient with small cell lung cancer (SCLC), who had a high serum level of soluble interleukin 2 receptors (sIL2-R) and was seropositive for human T cell leukemia virus (HTLV)-l. KHM-3S cells were positive for IL2-R (Tac) and NKH-1, but negative for other lymphocytic markers such as OKT 11, OKT 4, OKT 8, T cell receptor (WT 31), B 1, and B 4. Moreover, the KHM-3S cells were negative for leukocyte common antigen and strongly positive for neuron-specific enolase (NSE). Secretion of sIL2-R and NSE by the KHM-3S line was detected by an enzyme-linked immunosorbent assay. Rearrangement of the T cell receptor gene and monoclonal HTLV-1 integration were found by Southern blot analysis of KHM-3S DNA. However, Northern blot analysis showed no T cell receptor mRNA. KHM-3S may be useful for studies on the role of HTLV-1 in carcinogenesis and IL2-R expression in SCLC.  相似文献   
994.
7例晚期瘤性胸水的肿瘤浸润淋巴细胞(TIL)经体外诱导培养3~12d,扩增1~9倍.其CD8及IL-2R阳性细胞百分率增加2.43和2.76倍;NK活力增加3.29倍,与培养前后比较有显著差异。TIL/rIL-2(重组人白细胞介素2)胸腔内回输后,4例胸水及胸水中肿瘤细胞消失,癌胚抗原(CEA)回至正常水平,2例胸水减少,1例因多房性胸水停止治疗,CEA水平上升。经1~8个月随访患者心、肝、肾功能正常。  相似文献   
995.
996.
Patients with stage T3N0~2M0 gastric carcinoma (n = 108) were studied for relevant prognostic factors. Peritoneal lavage cytology (PLC) was performed in all. In univariate analysis, 5-year survival rates were better with smaller serosal invasion (diameter <3.0 cm vs. ≥3.0 cm, 61% vs. 37%, P < 0.05) and fewer metastatic nodes (≤5 vs. ≥6, 57% vs. 29%, P < 0.05). In multivariate analyses, only these two factors were significant. The predictive value of PLC was not shown in both univariate and multivariate analyses. Peritoneal recurrence occured in 14 (22%) of 77 patients with negative PLC, and in 3 (18%) of 17 with positive PLC, the difference being not significant. Our results indicate that PLC is insensitive in predicting the development of peritoneal recurrence. Its role in the estimation of survival is limited, as many will die of visceral or locoregional recurrence if not of peritoneal dissemination.  相似文献   
997.
本文观察16例大肠癌病人的癌组织培养上清液对人T细胞的增殖,ZL—2产生的影响和病理Dukes分期的关系,发现癌组织的TDSF对T细胞的增殖有显著抑制作用,对ZL—2的产生抑制作用不明显,对T细胞增殖率在DukesA与B期,其值与对照有显著差异(0.01P<0.05).在C期有非常显著差异(P<0.01).说明大肠癌组织确实分泌有能造成宿主免疫功能下降的抑制物质.且免疫作用不是通过ZL—2环节发生.  相似文献   
998.
Summary Expression of IGF-I and IGF-II was studied in human breast cancer tissues by in situ hybridization. IGF-I mRNA was detected only in stromal cells adjacent to normal breast epithelial cells. Stromal cells associated with the tumor cells did not contain IGF-I, nor did malignant or benign breast epithelial cells. In contrast, IGF-II mRNA was found in both the malignant epithelial cells and their adjacent stromal cells. These data imply that stromal cells associated with breast epithelium may switch expression from IGF-I to IGF-II during breast cancer evolution. This appearance of IGF-II expression may identify cancer-associated stromal cells that have a fetal phenotype.  相似文献   
999.
目的 提高胃上部癌外科治疗水平。方法 对94例胃上部癌采用了经腹正中切口或合并切除剑突及左第7~9肋弓软骨入路,行近端胃或全胃切除术。结果 全组病例发生吻合口瘘1例,食管断端癌残留3例和肺部感染8例,无肋软骨炎及胸膜损伤所致血气胸发生。结论 胃上部癌经腹入路暴露良好,创伤小,痛苦少,适用于食管无浸润或浸润小于1cm的胃上部癌的患者。  相似文献   
1000.
为了提高肺癌细胞学分型的准确性,对142例痰液细胞学阳性的肺癌病例与其病理组织学进行对比观察。结果表明痰液细胞学与组织学分型总符合率80.70%。在涂片中发现,小细胞癌形态特征较强,分型符合率最高(92.5%),鳞癌与腺癌中分化高者分型特征明显,而分化低者分型特征不明显,故符合率较低(68.63%及85.71%),在检查中应仔细寻找特征性细胞,以免漏诊。  相似文献   
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