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991.
False negative rates were compared in two screening modalities, physical examination with or without mammography, in an intervention study for women aged over 50 in Miyagi Prefecture. Thirty-five breast cancers were detected in 12,515 subjects who participated in the trial consisting of physical examination and mammography, whereas 44 breast cancers were detected in 50,105 subjects who received physical examination alone, so that the detection rates were 0.28% and 0.09%, respectively. Among 50,061 subjects who received physical examination alone, 8 women were diagnosed as having breast cancer within 12 months after the screening, while only one of 12,480 screenees receiving the combined modality was so diagnosed, implying false negative rates of 15.4% and 2.8%, respectively. When the screening sensitivity in the combined system was analyzed according to each single modality, the false negative rate provided by physical examination with mammography turned out to be 2.8%, significantly lower than that (33.3%) by the physical examination alone. Minimal breast cancers represented 25.7% of all screen-detected cancers in the combined modality, compared with 9.1% in the modality without mammography. The trial thus indicates that physical examination combined with mammography may be an appropriate modality for breast cancer screening in women aged over 50 on the basis of screening sensitivity.  相似文献   
992.
993.
本研究探讨了白细胞介紊10(IL-10)对小鼠体内抗肿瘤免疫功能的影响。鉴于C26结肠癌细胞转染了IL-10基因后在体内的致瘤性明显下降,本研究构建了一株对C26结肠癌细胞具有杀伤括性的CD8^ CTL并观察了IL-10基因转染的该细胞株对肿瘤的治疗作用。携带IL-10基因的重组腺病毒能有效介导小鼠琳巴细胞的基因转染并使之分泌较高水平的IL-10。IL-10基因转染的CTL过继回输荷瘤小鼠体内能明显增强荷瘤小鼠的体内抗肿瘤免疫功能,使实验性肺转移小鼠肺部转移结节数明显减少.这表明,IL-10对于过继回输的肿瘤特异性CTL的免疫功能具有明显的增强作用。  相似文献   
994.
995.
Cellular localization of amylase in various ovarian tumors was studied by the immunoperoxidase method using an antibody to human pancreatic amylase. Amylase was present in eight of 34 serous carcinomas and eight of 27 endometrioid carcinomas. However, only in one poorly differentiated serous carcinoma and two well-differentiated endometrioid carcinomas were a large number of amylase-reactive cells found. Five benign and three borderline serous tumors contained no amylase. Also, amylase was not detected in any of 34 mucinous tumors or five malignant clear cell tumors. The results obtained suggest that amylase will be a useful tumor marker, when present, for follow-up of endometrioid and serous carcinomas of the ovary.  相似文献   
996.
The influence of antecedent renal disease on pregnancy was studied retrospectively in 72 women with various renal diseases that had been proved by biopsy. Among 105 pregnancies studied, normal deliveries were observed in 74 (71%), abnormal deliveries with live infants in 14 (13%), fetal or neonatal deaths in 11 (10%), and spontaneous abortions in six (6%). The incidence of normal delivery, as well as that of live births, was the highest in the cases of membranous glomerulonephritis, but there was no obvious difference in the incidence among IgA nephropathy and non-IgA proliferative glomerulonephritis. Cases in which there were tubulointerstitial changes of the cortical area or arteriosclerosis in biopsy specimens and cases that included hypertension (greater than 140/90 mm Hg) or decreased renal function (glomerular filtration rate, less than 70 ml/min) were clearly associated with an unfavorable outcome in delivery. It was concluded that assessment of the advisability of pregnancy in nephritic women should be made on the basis of a combination of the clinical and histologic parameters.  相似文献   
997.
998.
999.
Collagen fibrils in nanophthalmic sclerae   总被引:2,自引:0,他引:2  
PURPOSE: To examine collagen fibrils in 3 nanophthalmos sclerae and to compare them with normal control sclerae morphometrically. MATERIALS AND METHODS: Three cases of nanophthalmos associated with uveal effusion were studied. When sclerectomy was performed, scleral specimens were collected and fixed with 3% glutaraldehyde/2.5% paraformaldehyde. After epon-embedding and ultrathin sectioning, they were examined by transmission electron microscopy. Collagen fibrils from both nanophthalmos and normal control sclerae were compared in diameters and numbers per micron 2 areas. RESULTS: All scleral tissues from the three cases were associated with irregularly woven and unclear collagen bundles. Several abnormal findings, such as twisting or fraying, were also detected in a few collagen fibrils. The diameter and density of normal-appearing collagen fibrils that occupied most areas of nanophthalmos sclerae were the same as those from normal control sclerae morphometrically. CONCLUSIONS: Although nanophthalmos sclerae even with uveal effusion showed thick irregular collagen bundles and a few abnormal collagen fibrils, most collagen fibrils appeared the same as normal controls.  相似文献   
1000.
Between June 1987 and June 1988, 28 patients (28 tumors) withliver, retroperitoneal, intrapelvic, or superficial tumors weretreated with hyperthermia combined with radiotherapy and/orchemotherapy. Hyperthermia was administered once or twice aweek for 30-60 min per session, up to a total of 2–11sessions, with an 8-MHz RF capacitive heating device. Bloodflow in the tumors was evaluated from the rate of thermal clearance(TCR) using the bio-heat transfer equation. The TCR was measuredin the middle of the first heating session and at the end ofthe last heating session by turning off the output power ofthe heating device. For 9 patients, contrast-enhanced CT scanswere taken and CT numbers at the centers of tumors were measuredbefore and after the entire course of hyperthermia. Changesin TCR were closely related to average tumor center temperature,changes in CT number, and tumor response. When smaller and moresuperficial tumors were treated by hyperthermia combined withradiotherapy and/or chemotherapy that consisted of many heatingsessions and during which a high average tumor center temperaturewas achieved, a better tumor response was obtained. The betterthe tumor response, the higher the local control rate became.The cause-specific survival rate of patients who achieved goodtumor responses was higher than that of patients who showedpoor tumor responses. Changes in TCR and CT number in heatedtumors were useful and important indicators of tumor responseto hyperthermia.  相似文献   
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