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Our previous study demonstrated that pro-gastrin-releasing peptide(31–98), or ProGRP, is a specific tumor marker in patients with small cell lung carcinoma (SCLC). Using a newly developed, highly sensitive enzyme-linked immunosorbent assay (ELISA) for ProGRP, we analyzed 1,446 samples including those obtained from 478 lung cancer patients to evaluate the clinical usefulness of this ELISA. Several properties indicated that ProGRP is a useful tumor marker for SCLC. First, ProGRP was specifically elevated in SCLC patients. In non-SCLC patients and patients with non-tumorous lung diseases, its serum level was very rarely elevated. Secondly, ProGRP was a reliable marker, in terms of the marked elevation of serum ProGRP levels in SCLC patients. Thirdly, serum ProGRP levels were elevated in SCLC patients even at a relatively early stage of this disease. Fourthly, changes in the serum ProGRP level showed an excellent correlation with the therapeutic responses in SCLC patients. Neuron-specific enolase (NSE) is accepted as a tumor marker of SCLC patients. With the aim of comparing ProGRP and NSE as tumor markers for SCLC patients, we measured serum NSE levels in all samples collected in the present study. We found that ProGRP was superior to NSE in terms of sensitivity, specificity and reliability. Therefore, we consider that ProGRP can play a major role as a clinical tumor marker for SCLC patients.  相似文献   
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RTI-121 and RTI-122 are 3 beta-substituted phenyltropane analogs of cocaine that have high, selective binding affinity for dopamine transporters. [123I]RTI-121 and [123I]RTI-122 bind to dopamine transporters in vivo after intravenous administration and permit imaging of the transporters.  相似文献   
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The authors used positron emission tomography (PET) and 11C-labeled glucose to study 15 unmedicated patients with affective disorders and 7 control subjects. Diagnoses of affective disorders were based on DSM-III criteria, and symptomatology was evaluated by the Hamilton Rating Scale for Depression. Blood counts of 11C in both unipolar and bipolar patients did not differ from those in controls after oral administration of 11C-glucose. By contrast, brain counts of 11C in unipolar depressed patients were significantly lower, whereas those in bipolar manic patients were significantly higher, than in normal controls.  相似文献   
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The histochemical demonstration of iron and the iron content was examined in the brain of a case of the special type of hepatocerebral encephalopathy (HCE). The patient had suffered from a liver disease since 36 years old. At 44 years old, she experienced the first attack of twilight state with flapping tremor. She had predilection for eating beans. Her personality gradually became euphoric with the recurrent episodes of unconsciousness. At 54 years old, she died of the complication of melena, renal insufficiency and pneumonia. The liver showed cirrhotic changes and iron content of liver was 0 or 1 after MacDonald's criterion scale. The histopathological findings of the brain showed the characteristic changes of HCE, which were incomplete softening and spongy state pseudolaminarilly extending in the deep layer of the cerebral cortex, the proliferation of the severely changed Alzheimer 2 type glia with or without intranuclear carmine positive substance. The deparaffinized sections, 20 mu in thickness, which were not fastened on slides were used for the histochemical study of iron, because iron deposits displaced inside of the brain tissues when the paraffin sections were fastened on slide glasses in the constant-temperature bath. The iron deposition was found in the central gyrus, superior temporal gyrus, medial and lateral occipito-temporal gyrus and middle temporal gyrus of occipital lobe. The iron accumulated in the ground substance, glia cell bodies, glia nuclei and unknown bodies in the 3-6 layers of cerebral cortex of these gyri. The iron accumulation demonstrated histochemically in other parts of the brain were group 1, 2 by Spatz, mammillary body, glia cell bodies in cerebellar white matter and pons.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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Light and electron microscopic studies have been made on an anaplastic giant-cell tumor that developed in a woman 8 years after an operation on the thyroid for papillary carcinoma. Many giant cells were observed in the anaplastic tumor tissue, but no follicles. Numerous tightly-packed mitochondria and abundant ribosomes were present, but there were no desmosomes. The basement membrane was not distinct.  相似文献   
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To investigate the relationship between human T-lymphotropic virus (HTLV) types I and II and the pathogenesis of autoimmune thyroid diseases, we examined serum anti-thyroid antibodies in 1019 blood donors with or without serum anti-HTLV-I antibody as well as proviral DNA for HTLV-II in leukocyte DNA by the polymerase chain reaction in 395 blood donors with or without anti-thyroid antibodies. The frequency of donors with anti-HTLV-I antibody who also showed anti-thyroid antibodies (7.9%) tended to be higher than that (6.3%) among donors who did not have the anti-HTLV-I antibody. The frequency of anti-thyroid antibodies in 125 young male donors aged 16–39 years with anti-HTLV-I antibody (4.8%) was significantly higher (P<0.05) than that (0.6%) in 164 control donors without the antibody. In blood donors with anti-thyroid antibody, 25.0% of those with anti-HTLV-I antibody and 14.3% of those without the antibody had HTLV-II proviral DNA. In contrast, in donors without anti-thyroid antibody HTLV-II proviral DNA was detected in 2.3% of those with anti-HTLV-I antibody and in 0.6% of those without the anti body. Thus the detection rates in donors with anti-thyroid antibody were significantly higher (P<0.001) than those in donors without the antibody, regardless of HTLV-I infection. These results suggest that HTLV-I infection and the presence of HTLV-II proviral DNA may be independently related to the pathogenesis of autoimmune thyroid diseases.Abbreviations HTLV Human T-lymphotropic virus - PCR Polymerase chain reaction  相似文献   
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INTRODUCTION: Orotate phosphoribosyl transferase (OPRT), dihydropyrimidine dehydrogenase (DPD), and thymidylate synthase (TS) are initial key enzymes in the 5-fluorouracil (5-FU) metabolic pathway. The expression levels and activities of these three enzymes play important roles in the response of cancer patients to 5-FU-based chemotherapy. PURPOSE: The purpose of this study was to investigate the relationship between the activities of 5-FU metabolic enzymes and clinicopathologic factors in colorectal cancer. METHODS: We measured the activities of OPRT, DPD, and TS in colorectal cancer tissues. We also investigated the correlations between the activities of these three enzymes and clinicopathologic factors (histological type, depth of tumor invasion, extent of lymph node metastasis, Dukes' stage, lymphatic invasion, and vascular invasion). We examined 100 patients with surgically resected colorectal cancer. RESULTS: Poorly differentiated adenocarcinoma showed significantly higher DPD activities than did moderately differentiated or well-differentiated adenocarcinoma. In patients with lymph-node metastasis, OPRT activity was significantly lower than in patients without lymph-node metastasis. No significant relation was found between TS activity and histological type, depth of tumor invasion, extent of lymph node metastasis, Dukes' stage, lymphatic invasion, or vascular invasion. CONCLUSION: The response to 5-FU may be poor in patients with lymph-node metastasis, because of low OPRT activity, and in patients with poorly differentiated adenocarcinoma, because of high DPD activity.  相似文献   
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