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971.
Tumor necrosis factor (TNF)-inducing activities of lipid A preparations from P. diminuta and P. vesicularis, which contain mainly 2 mol of 2,3-diamino-2,3-dideoxy-D-glucose and 1 mol of nonglycosidic phosphate as the backbone component and have partly different fatty acid compositions, were examined. TNF was induced by injecting various lipid A fractions into mice that had previously been sensitized with Mycobacterium bovis BCG vaccine. A major component of lipid A of both strains, referred to as A3 fraction, exhibited stronger TNF-inducing activity than A2 fraction having incomplete acyl residues. The removal of ester-linked fatty acyl groups by mild hydrazinolysis of the P. diminuta lipid A results in a marked decrease of the activity. These results suggest that the structure of the hydrophobic part, including the amide-linked acyloxyacyl group(s), of the lipid A molecule play an important role in inducing TNF in the sera of mice.  相似文献   
972.
973.
A lymphoepithelial cyst is reported. A 68-year-old man consulted a surgeon, presenting with a sense of abdominal fullness. Ultrasonography and computed tomography revealed a large tumor, 10 cm in diameter, behind the head of the pancreas. Celiac arteriography at our hospital showed feeding arteries from the dorsal pancreatic artery and the pancreatic arcades. CA19-9 was elevated to 178 U/ml. Laparotomy was performed. The tumor was well demarcated from the surrounding tissue by a fibrous capsule and there was no continuity to the pancreatic parenchyma. Simple tumorectomy and distal gastrectomy for peptic gastric ulcer disease were performed. The cut surface revealed a multicystic lesion containing atheromatous substances. Histopathologically, the internal surface of the cyst was lined with stratified squamous epithelium containing mucin-producing cells; many germinal centers were observed in the cyst wall.  相似文献   
974.
The effects of volatile anesthetics, i.e., methoxyflurane, halothane and enflurane, on the electroretinogram (ERG) were studied in 15 albino rabbits. The ERG was analyzed in terms of the a-wave, and the first oscillatory component (01) in the b-wave. The 01 peak latency showed a significant dose-related prolongation when anesthetic end-tidal concentrations were in excess of 0.8 minimum alveolar concentration (MAC). One MAC, a measure of anesthetic potency, is the end-tidal concentration of an anesthetic at 1 atmosphere that induces immobility in 50% of animals against a noxious stimulus. The amplitudes of the a-wave and the 01 decreased in dose-dependent manners, but their changes were less striking than those of the 01 latency. The peak latency of the a-wave remained unchanged. We conclude that the 01 peak latency is a useful monitor of the depth of inhalational anesthesia.  相似文献   
975.
976.
The effects of cell surface sugar chains combined with certain gene amplifications of breast cancers on the prognosis of patients were studied and the relationships between the sugar chains of cancer cells and amplifications of the proto-oncogenes c-myc, int-2 and c-erb B-2, evaluated. One hundred and fifty three human breast carcinoma tissues were investigated by an immunohistochemical technique using the avidinbiotin-peroxidase method with 1 lectin (HPA; Helix Pomatia) and 4 monoclonal antibodies (B-72-3, St-439, anti-Tn and anti-T). The positive rates of HPA, St-439, B-72-3, anti-Tn and anti-T were 43 per cent (63/153), 52 per cent (80/153), 53 per cent (81/153), 64 per cent (98/153) and 89 per cent (136/153), respectively. Patients whose cancers had positive HPA staining were found to have a lower survival rate than those with negative HPA staining (p<0.05), whereas those whose cancers had positive St-439 staining showed a better prognosis than those with negative St-439 staining (p<0.01). The positive rate of HPA was related to the gene amplification of c-myc proto-oncogene (p<0.01), whereas the negative rate of St-439 was correlated with the gene amplification of c-erb B-2 (p<0.01). These data indicate the prognostic value of HPA and St-439 and also the relationships between the gene amplifications and carbohydrate structures in breast cancer cells.  相似文献   
977.
Sixteen cases of primary renal pelvic tumor treated at our Department between July, 1971 and June, 1984, were reviewed. The sixth decade predominated over other age groups and occupied 47.3% of all cases (average: 63.9 years). The sex ratio was 4.3:1 with male patients predominating over female patients. The incidence of the affected side was equal; 8 cases in the right and 8 cases in the left renal pelvis. The most common initial symptom was macroscopic hematuria in 13 cases (81.2%), followed by flank pain in 2 cases (12.5%). The major findings in IVP were filling defect in 11 cases (68.7%) and non-visualizing kidney in 4 cases (25.0%). Positive urinary cytology was obtained in 6 cases (49.1%) by voided urine specimen and 4 cases (50.0%) by catheterized urine specimen. Histologically, all cases were transitional cell carcinoma; 11 of them were low stage and 5 were high stage at the initial diagnosis. Nine patients(56.1%) were treated by total nephroureterectomy associated with partial cystectomy. The over all survival rate at 1,2,3,4 and 5 years was 86%, 78%, 78%, 68% and 68%, respectively, by the Kaplan-Meier method. The five year survival rate was 80% for the low stage group and 0% for the high stage group. (p less than 0.05, generalized Wilcoxon test). The five year survival rate was 83% for the low grade group and 40% for the high grade group. (p less than 0.05, Generalized Wilcoxon test) Among several factors, stage and grade of the tumor were the most influencing factors for prognosis.  相似文献   
978.
A case of breast tumor is described, which consisted of dense and uniform proliferation of ducts and lobules composed of both epithelial and myoepithelial cells and in which multiple foci of adenocarcinoma were observed. The tumor surrounding the carcinoma foci was identified as 'adenomyoepithelial adenosis'. Adenomyoepithelial adenosis was not monoclonal by clonal analysis, but revealed a relatively high labeling index for proliferating cell nuclear antigen by immunohistochemistry. Although it was still undetermined whether adenomyoepithelial adenosis is a non-clonal nonneoplastic lesion or a biclonal neoplastic one, the lesion was shown to reveal high proliferative activity in both glandular epithelial and myoepithelial cells and was considered to be prone to progress to obvious carcinoma.  相似文献   
979.
Summary We examined the fine structural distribution of glycogen particles in the cells of the erthrocyte series from thirty individuals with or without hematological disorders using the periodic acid-thiocarbo hydrazide-silver proteinate (PA-TCH-SP) technique, which is known to extend PAS staining to the ultrastructural level. In diseases exhibiting dyserythropoiesis, such as refractory anemia with excess of blasts (RAEB) and juvenile chronic myelocytic leukemia (JCML), glycogen particles remarkably increased. In diseases showing hypererythropoiesis such as iron deficiency anemia, hemolytic anemia, or in cells obtained from very small premature infants, an increase in glycogen particles was observed in most cases. Compared to the PAS staining technique, which also utilizes the periodic acid reaction, the PA-TCH-SP technique appears to be more sensitive for visualizing glycogen particles in PAS negative cells, in addition to its capability of demonstrating the distribution of periodate reactive substance at the fine structural level.  相似文献   
980.
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