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11.
Autopsy cases of lung cancer, 41,988 in males and 13,818 in females, consecutively registered between 1958 and 1987, were analysed statistically and compared with other case materials and mortality statistics. Cases of malignant tumor showed a gradual increase, and now comprise 60% of the total male and 55% of the total female autopsy cases. The percentage of lung cancer cases among the total autopsy cases was 9% for males and 5% for females. The percentage of lung cancer cases among total cases of malignant tumor was about 17% for males and 9% for females. Among fatal malignant tumors, gastric cancer and lung cancer showed the highest frequency. The relative incidence of gastric cancer was seen to decrease, whereas that of lung cancer increased. Of the histological types of lung cancer in both sexes, adenocarcinoma was the most frequent, followed by squamous cell carcinoma. During the period studied the peak age of patients with lung cancer shifted from the seventh to eighth decade, and a significant elevation of mean age was demonstrated for all of the major histological types in both sexes. The male:female ratio for all lung cancer cases was 3.0, which was much lower than those for the United States and Europe, but very similar to the ratios of mortality statistics in Japan and other Asian countries. As a result of a previous autopsy study at the University of Tokyo, it was also confirmed that the male:female ratio relative to age in each country reflects very well the histological distribution.  相似文献   
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A sandwich radioimmunometric assay using monoclonal antibodies 6G10 and SV2-61 gamma directed to the extracellular domain of the c-erbB-2 oncogene product was developed and the antigen levels in sera from normal donors and patients with breast carcinoma were determined. The antigen levels in normal donors were uniformly low (9.52 +/- 0.91 ng/ml) and 3.0% (2/66 cases) slightly exceeded the cutoff value (11.4 ng/ml). In patients with breast carcinoma, serum c-erbB-2 protein levels increased and the positivity was as high as 45.7% (16/35 cases) in recurrent cases. Determination of c-erbB-2 protein may be a useful marker for serological diagnosis of breast carcinoma.  相似文献   
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This report summarizes the clinicopathologic findings in 11 cases of low papillary carcinoma of the breast accompanied by the morphologic feature of mucus leakage into the mammary stroma. These cases were characterized by two morphologic findings. First, abundant mucus produced by the tumor cells filled the intraductal spaces where neoplastic epithelium formed very low papillary projections, ie, a feature of mucinous-producing low papillary carcinoma in situ. Second, there was expansive leakage of mucus into the mammary stroma occasionally accompanied by a few epithelial cells. All the cases showed a high level of mucus production and contained no elements of invasive ductal carcinoma or ordinary invasive mucinous carcinoma. These cases have no evidence of direct invasion of the mammary stroma by malignant cells. The average age of the 11 patients was 41 years. Foci of microcalcification were seen in some tumors (seven cases; 64%). There were no cases with lymph node metastases. All the patients underwent mastectomy with no adjuvant therapy, and they are currently alive and well.  相似文献   
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The effects of short-term (7 days) feeding of a diet containing cholestyramine (5%) on the cholesterol metabolism were studied in male Sprague-Dawley rats at ages of 5 weeks (young) and 9-10 months (adult). Cholestyramine significantly enhanced the activities of hepatic 3-hydroxy-3-methylglutaryl coenzyme A reductase and cholesterol 7 alpha-hydroxylase both in young and adult rats; however, the absolute values were significantly higher in the former. The time-courses of changes in the activities of these enzymes after cessation of cholestyramine were comparable in both groups of rats. The rate of incorporation of mevalonate into sterol was also higher in young than in adult rats, while the stimulating effect of cholestyramine was markedly greater in adult rats. Hepatic acyl-CoA:cholesterol acyltransferase activity was comparable, but cholestyramine significantly decreased it only in adult rats. In adult rats hepatic cholesterol was decreased significantly by the resin while it remained uninfluenced in young rats. The serum cholesterol level tended to be higher in adult rats regardless of the dietary manipulation. The results indicate an appreciable age-dependent change in the hepatic cholesterol metabolism in response to the interruption of enterohepatic circulation of bile acids.  相似文献   
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Hybridomas producing human monoclonal antibodies (mAb) against varicella-zoster virus (VZV) were generated by fusing human splenic lymphocytes with mouse myeloma cells. Before cell fusion, lymphocytes were stimulated in vitro with viral antigens and pokeweed mitogen. This combination synergistically increased the generation of VZV-specific hybridomas. Five established hybridomas have been stably producing mAb for at least 9 months. These mAb, designated V1, V2, V6, V8 and V9, were of the IgG1, lambda isotype. They bound to all 6 tested VZV strains but not to other herpes viruses, with the exception that V1 bound to herpes simplex virus (HSV) as well as VZV. Immunoprecipitation analysis showed that V1, V6 and V9 recognized glycoprotein gpII, whereas V2 and V8 recognized gpI. In addition, V1 reacted with the gB glycoprotein of HSV. All these mAb neutralized viral infectivity. The neutralizations by V2 and V8 were more effective and more complement dependent than those by V1, V6 and V9. Immunofluorescence tests revealed that all these mAb bound to the surface membrane of VZV-infected cells. These results suggest that cell fusion between in vitro stimulated lymphocytes and mouse myeloma cells is a reliable method for the generation of hybridomas capable of stable production of human mAb. The human mAb thus developed may provide a new means of passive immunization of humans against VZV infection.  相似文献   
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Retinoblastomas exhibit a unique form of differentiation to produce cell elements similar to those seen in a photoreceptor cell. An ultrastructural study was performed on 29 cases of retinoblastoma to further clarify the cytologic characteristics of the tumor cells. The age of the retinoblastomas averaged 17.1 months and the tumor cells showing photo-receptor differentiation were demonstrated in 10 cases (35%). The findings were especially notable in retinoblastomas with Flexner-Wintersteiner rosette formation (seven cases, 28%). Similar photoreceptor differentiation was also evident in solid cell clusters without rosette formation (four cases, 14%). The presence of photoreceptor elements was assumed to be significantly frequent both in Flexner-Wintersteiner rosettes and in the solid cell clusters. The cell cytoplasm also showed proliferation of long mitochondria and microtubules, reflecting photoreceptor differentiation. The hereditary-type retinoblastoma showed more advanced cell differentiation than the non-hereditary type. Photoreceptor differentiated retinoblastoma showed rather indolent growth compared with the undifferentiated type, and the former can expect a curative treatment by operation. These observations provide additional findings of the biological nature of retinoblastomas.  相似文献   
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A 69-item questionnaire measuring generic functioning and well-being and disease-specific health outcomes was developed and tested using the pre-treatment data from patients with chronic hepatitis C (CHC) participating in two randomized trials of interferon -2b (n = 157). The questionnaire included all eight scales from the SF-36 and measures of nine other generic and disease-specific health concepts. Psychometric tests confirmed the assumptions underlying the construction and scoring of all generic and disease-specific scales. Cross-sectional tests of known groups validity showed that CHC patients scored worse on the generic scales than patients with other chronic conditions and worse than a healthy general population. The generic and disease-specific scale scores were lower in the presence of physical findings of CHC, as hypothesized, but only the physical functioning and bodily pain scales were linked to cirrhosis or extreme alanine aminotransferase (ALT) ratios. This instrument will be useful in studies of health outcome among patients with CHC, a condition whose health burden appears to have been underestimated in studies to date.  相似文献   
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