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991.
Parathyroid cancer is rare but relatively frequent in Japan compared to Western countries. Surgical parathyroidectomy is the primary choice for radical treatment of primary hyperparathyroidism (pHPT), hence it is important to distinguish malignant from benign tumor in the determination of surgical indication as well as method of operation. However, it is not easy to diagnose parathyroid cancer prior to operation. In the present study, we analyzed the background data, biochemical data and bone mineral density (BMD) of 131 patients with pHPT (111 benign and 20 malignant). BMD of the lumbar spine and mid-radius was measured by dual-energy X-ray absorptiometry. Serum levels of calcium, alkaline phosphatase (ALP), and parathyroid hormone (PTH) were significantly higher in malignant group compared to benign one. The extent of elevation of mid PTH seemed to be higher than that of intact PTH in malignant group. Age-, gender-, and race-adjusted BMD of distal one-third of radius was significantly decreased in malignant group compared to benign one, although that of lumbar spine was not significantly different between the two groups, indicating that osteopenia was marked in the region which was rich in cortical bone in malignant group. On the other hand, serum levels of calcium, ALP, and mid PTH as well as age were selected as predictors of malignancy in univariate logistic regression analysis, while serum level of intact PTH was not selected. In conclusion, radial BMD was lower in malignant group compared to benign one in pHPT. Serum levels of calcium, ALP and mid PTH were useful to predict malignancy of affected parathyroid glands in pHPT patients.  相似文献   
992.
OBJECTIVE: Pleurodesis using chemical agents has been applied to high-risk patients with pneumothorax. This treatment, however, is sometimes unsuccessful in patients with intractable pneumothorax or intrapleural dead space. We developed a technique for the intrapleural administration of diluted fibrin glue as a treatment for such patients. METHODS: Fibrin glue was diluted fourfold with saline solution and/or contrast medium. Pleurodesis with a large amount of the diluted fibrin glue was performed in 40 high-risk patients with intractable pneumothorax and in 13 postthoracotomy patients with persistent air leakage associated with an intrapleural dead space. RESULTS: The air leaks were stopped by administration of the glue in all patients of both groups. During the follow-up period, a recurrence rate of 12.5% was observed in the former group. These recurrent pneumothoraces also were successfully treated by glue administration with no further recurrence. In the 13 postthoracotomy patients, there was no recurrence after the initial treatment. Pyrexia (12.5%) and chest discomfort (4.1%) were observed as side effects, but there were no findings of severe chest pain or thoracic empyema. CONCLUSIONS: These results suggest that intrapleural administration of a large amount of diluted fibrin glue is a useful treatment for intractable pneumothoraces in high-risk or postthoracotomy patients who have an intrapleural dead space.  相似文献   
993.
To identify and quantify the amount of viable hibernating myocardium in patients with chronic coronary artery disease, resting 201Tl single photon emission computed tomography (SPECT) was compared with 99mTc-methoxy-isobutyl isonitrile (MIBI) SPECT after nitrate infusion (nitrate-99mTc-MIBI) and 201Tl SPECT after 201Tl with glucose-insulin-potassium infusion (201Tl-GIK) in 25 patients. Twenty-one patients also underwent completely left ventriculography beforehand and 5+/-4 months afterwards. SPECT images were divided into 9 segments and scored visually from 0 (normal uptake) to 3 (absent). The defect score was calculated as the summation of the total scores (TDS) in each patient. The TDS of nitrate-99mTc-MIBI images (6.3+/-4.3) and 201Tl-GIK images (5.8+/-4.2) were significantly lower than the 7.4+/-4.3 of resting 201Tl images (p<0.01). Based on the improvement of wall motion after coronary revascularization, the sensitivity of 201Tl-GIK imaging (85%) was significantly higher (p<0.05), and that of nitrate-99mTc-MIBI imaging (79%) also tended to be higher (p=0.08), than that of 201Tl imaging (62%) in detecting viable myocardium. The specificity of the 3 methods was almost the same. The nitrate-99mTc-MIBI and 201Tl-GIK methods were more useful than the resting 201Tl method for evaluating viable hibernating myocardium. Furthermore, the 201Tl-GIK method may provide a more accurate estimate of the amount of viable myocardium than the nitrate-99mTc-MIBI method.  相似文献   
994.
Farber disease is a rare lysosomal storage disease, characterized by the accumulation of ceramide in tissues due to acid ceramidase deficiency. Here we report the identification of three novel mutations in the acid ceramidase gene from two Japanese patients. Patient 1 showed joint problems at around 10 months of age and the patient is now emaciated, with multiple nodules and mild neurological problems at 10 years of age. Patient 2 had consanguineous parents and showed joint contractures at around 8 months of age. He showed neurological symptoms around 2 years of age and died at 6 years owing to respiratory failure. The diagnosis was made clinically and was confirmed by enzymatic assay of acid ceramidase. Molecular analysis of cultured skin fibroblasts showed normal mRNA levels expressed in both patients. By direct sequencing of cDNA, missense mutations of V97E in exon 4 and G235R in exon 9 were detected in patient 1 and 96delV in exon 4 was homozygously identified in patient 2. These mutations were also confirmed in genomic DNA. Expression of mutated acid ceramidase cDNA in COS-1 cells showed acid ceramidase activity decreased to 35%, 2% and 37% of control value, respectively. We also found a new polymorphism V369I in exon 14 in the allele from the mother of patient 1. To date, 13 mutations, including our newly identified mutations, have been reported. All these mutations were genetically private and genotype–phenotype correlations could not be made.  相似文献   
995.
Solid-phase radioimmunoassays using monoclonal antibodies were used to assay antibody to hepatitis B core antigen of immunoglobulin A class in terms of polymeric and monomeric forms, as well as of IgA1 and IgA2 subclasses, in the serum of persons infected with hepatitis B virus. The level of secretory immunoglobulin A antibody was significantly higher in patients with acute hepatitis (mean +/- S.E., sample per normal ratio = 29.2 +/- 1.9) than that in asymptomatic carriers (2.1 +/- 0.1), patients with chronic persistent hepatitis (3.5 +/- 0.5), patients with chronic active hepatitis (6.9 +/- 1.3) or patients with cirrhosis (5.8 +/- 1.1). In acute type B hepatitis, only polymeric immunoglobulin A antibody of either IgA1 or IgA2 subclass was detected. In contrast, in chronic infection, antibody to hepatitis B core antigen of IgA2 subclass was found in the polymeric form, but antibody of IgA1 subclass was detected in both polymeric and monomeric forms.  相似文献   
996.
A 62-year-old male was admitted to our hospital complaining of dyspnea in March, 2002. He had remarkable bone marrow invasion with a significant number of leukemic cells, anemia and thrombocytopenia. In addition he had generalized lymphadenopathy including a bulky mass in the left cervix. Surface marker analysis of abnormal cells showed CD 5+, 10-, 19+, 20+, 23+, and kappa+, and immunohistochemistry revealed cyclin D1-positive cells. Chromosome analysis showed del(11q). The patient was diagnosed as having mantle cell lymphoma, stage IVB, and received combination chemotherapy. He could not obtain complete remission and died after 29 months. We found it very difficult in this case to make a differential diagnosis between mantle cell lymphoma and chronic lymphocytic leukemia. We report on this case and summarize the problem of the differential diagnosis.  相似文献   
997.
M Naito  T Hayashi  M Kuzuya  C Funaki  K Asai  F Kuzuya 《Artery》1989,17(1):21-31
According to the response to injury hypothesis, endothelial migration and repair may play an important role in the initiation and progression of atherosclerosis. In this study, we examined the regulatory mechanisms of endothelial cell migration in vitro, using cultured endothelial cells from fetal bovine aortas. Dibutyryl cyclic AMP, 8-bromo cyclic GMP, and theophylline (each at concentrations of 10(-4) to 10(-3) M) inhibited the migration of endothelial cells. Migration was not significantly affected by the Ca2+ channel blockers diltiazem (10(-6) to 10(-4) M) and nicardipine (10(-6) to 10(-5) M) or by La3+ (10(-4) to 10(-3) M), an inorganic Ca2+-antagonist, TMB-8 (10(-6) to 5 x 10(-5) M), an intracellular Ca2+ blocker, or the calmodulin inhibitors W-7 (10(-6) to 5 x 10(-5) M) and trifluoperazine (10(-7) to 10(-5) M). At the extracellular Ca2+ concentrations of less than 0.2 mEq/l, the migration was inhibited significantly. In addition, migration was markedly suppressed by colchicine (10(-8) to 10(-5) M), an inhibitor of tubulin polymerization, and by cytochalasin B (10(-7) to 10(-5) M), an inhibitor of actin polymerization. These results suggest that cyclic nucleotides, such as cyclic AMP and GMP, may regulate the migration of vascular endothelial cells. Although a low concentration of extracellular Ca2+ is essential to their migration, participation of the intracellular Ca2+-calmodulin system was not evident in this study. It appears that the cytoskeletal system, including microtubules and microfilaments, is involved in the mechanisms of migration.  相似文献   
998.
Monoclonal antibodies specific for human thyroid peroxidase (TPO) were prepared by the hybridoma technique using hyperimmune spleen cells from mice immunized with TPO purified from thyroid glands from patients with Graves' disease. Use of the microenzyme-linked immunosorbent assay method revealed that some of the monoclonal antibodies cross-reacted strongly with human thyroglobulin (Tg). Conversely, monoclonal anti-Tg antibodies cross-reacted with TPO, albeit to a lesser degree. Some anti-Tg autoantibodies in serum from patients with chronic autoimmune thyroiditis purified by Tg affinity chromatography bound TPO, and such binding was completely inhibited by Tg. Western blotting experiments revealed that thyroid microsomal 103K proteins recognized by mouse monoclonal and polyclonal anti-TPO antibodies were recognized by some monoclonal anti-Tg antibodies and anti-Tg autoantibodies, and conversely, that 19S Tg was recognized by some monoclonal anti-TPO antibodies. TPO was immunoprecipitated by anti-Tg autoantibodies isolated by Tg affinity chromatography. On the other hand, the specificity for TPO of the anti-Tg autoantibodies was not identical with that of anti-TPO autoantibodies. These cross-reactivities were not due to contamination of TPO with Tg or vice versa, or to contamination of the anti-Tg autoantibody preparations with anti-TPO autoantibodies. Taken together, these data indicate that Tg and TPO share common antigenic determinants and that some of those determinants are recognized by autoantibodies in the serum of patients with chronic autoimmune thyroiditis.  相似文献   
999.
We identified a Japanese family with a beta-thalassaemia trait and hereditary elliptocytosis (HE). We studied five members of this family. One was normal, one had only the beta-thalassaemia trait, one had heterozygous HE, and two had compound heterozygous beta-thalassaemia trait and HE. The last two had already undergone splenectomy. The molecular profile of beta-thalassaemia was consistent with that of Hb Gunma: codon 127/128CAGGCT(Gln-Ala)--> CCT(Pro). Analysis of erythrocyte membrane proteins revealed a partial deficiency of protein 4.1 in all those with HE, whereas the spectrin content was within the normal range. Each heterozygous family member with either the beta-thalassaemia trait or HE was asymptomatic, whereas the two with both beta-thalassaemia and HE had marked red blood cell deformities and haemolysis. The abnormalities of the red blood cells in patients with the beta-thalassaemia trait might be enhanced by association with HE owing to a protein 4.1 deficiency.  相似文献   
1000.
Objectives: Liver histology in volunteer blood donors positive for serum hepatitis C virus RNA was investigated in relation to hepatitis C virus viremia levels. Methods: Twenty-one volunteer blood donors positive for serum hepatitis C virus RNA by polymerase chain reaction were monitored for at least 1 yr by monthly routine liver function tests and underwent liver biopsy. Liver histology findings were correlated with hepatitis C virus viremia levels assessed hy a quantitative branched DNA assay. Results: Liver histology showed the features of chronic hepatitis in 20 (95%) patients. Only one of the seven patients with persistently normal aminotransfer-ase levels during follow-up had normal liver histology, and the others had chronic hepatitis. Sera ohtained the same day of the liver biopsy were shown to contain hepatitis C virus RNA of 105.7–107.6 equivalent/ml (median 106.7). The total histological activity index score (median 2, range 0–15) and the scores of portal inflammation (median 1, range 0–3), lobular inflammation (median 1, range 0–4) and piecemeal necrosis (median 0, range 0–5) correlated with viremia levels ( r = 0.64, p < 0.01; r = 0.60, p < 0.01; r = 0.48, p < 0.05; and r = 0.49, p < 0.05, respectively). Conclusions: These findings suggest that chronic hepatitis is frequently caused by hepatitis C virus infection irrespective of the serum amino-transferase levels, and high level hepatitis C virus replication is a contributory cause for liver injury in volunteer blood donor populations.  相似文献   
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