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The alterations of second-messenger ligand binding and cerebral blood flow (CBF) were evaluated in the gerbil brain after 2-h unilateral common carotid artery occlusion. [3H]Forskolin (FK) and [3H]phorbol-12,13-dibutyrate (PDBu) were used as specific ligands for adenylate cyclase (AC) and protein kinase C (PKC) activity estimation, respectively. CBF was determined at the end of the experiment by the [14C]iodoantipyrine method. A quantitative autoradiographic method permitted simultaneous measurement of the three parameters in the same brain. The levels in the caudate-putamen, globus pallidus, and hippocampus were analyzed. The animals were divided into three groups: Group 1 with severe ischemia (CBF in the lateral nuclei of the thalamus (CBFt) less than 50 ml/100 g/min), Group 2 with mild ischemia (CBFt greater than or equal to 50 ml/100 g/min), and the Sham Group. The PDBu binding revealed a statistically significant increase in the caudate-putamen, lateral nuclei of the thalamus and hippocampus (CA1 and CA3 regions and dentate gyrus) on the ischemic side in Group 1 as compared to that in Group 2 and the Sham Group. In contrast, the FK binding did not show any significant changes in any of the regions. These data and our previous findings for 6-h ischemia suggest that (1) PKC translocation to the cell membrane may occur at the early ischemic phase in particular regions including the caudate-putamen, lateral nuclei of the thalamus and hippocampus, with the translocated PKC gradually diminishing during the subsequent ischemic period; and (2) the suppression of the AC system observed in 6-h ischemia may not appear in the early ischemic phase.  相似文献   
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Cardiovascular effects of (2'R)-4'-O-tetrahydropylanyladriamycin X HCl (THP) and doxorubicin (adriamycin, ADM) were studied in hamsters. In experiments to observe acute effects, THP was administered intravenously at a dose of 12.5, 25.0 or 50.0 mg/kg, and ADM at 1.56, 3.13 or 6.25 mg/kg was given to different subjects. The THP caused slight ECG alterations at a dose of 12.5 mg/kg. At a dose of 25.0 mg/kg or 50.0 mg/kg, THP caused moderate to remarkable alterations in ECG like a widening of PR and PRc interval, A-V block, ST segment depression and T wave flattening. The ADM caused moderate to remarkable alterations in ECG at a dose of 3.13 mg/kg or 6.25 mg/kg, including arrhythmia, bradycardia, A-V block, ST segment changes and T wave flattening. These changes caused by THP and ADM recovered within 5 approximately 10 minutes after injection. Alterations in the ultrastructure of the myocardium caused by THP at a dose of 50.0 mg/kg included some cells with slight changes like swelling of mitochondria, focal intracellular edema, and enlargement of myofibrils. The ADM, at a dose of 3.13 mg/kg, induced severer swelling of mitochondria than THP, dilatation of sarcoplasmic reticulum, intracellular edema, and disorganization of myofilaments. At a dose of 6.25 mg/kg of ADM, these changes became more pronounced. In experiments to observe subacute effects, hamsters were treated with THP or ADM by daily intraperitoneal injections for 15 consecutive days, and then allowed to be recovered for 15 days. Dose levels of THP or ADM were 0.125, 0.25, 0.5 and 1.0 mg/kg. General toxicity, ECG, hematological and blood biochemical analysis, and electron microscopic examination were studied. In the ECG study, THP-treated hamsters showed a reversible elevation of R wave amplitude at a daily dose of 0.5 mg/kg. Widening of PR and PRc interval, elevation of R and S wave amplitude, and reduction of T wave amplitude were observed at a daily dose of 1.0 mg/kg of THP. Hamsters treated with ADM showed increase of heart rate, reduction of T wave amplitude, and shortening of PR and PRc interval at a daily dose of 0.5 mg/kg. Severe changes were observed at a daily dose of 1.0 mg/kg of ADM including an increase of heart rate, elevation of R wave amplitude, reduction of S and T wave amplitude, and shortening of QT interval. The electron microscopic examination revealed that THP-treated hamsters showed separation of intercalated discs, formation of myelin structure, and dilatation of T-tubules at a daily dose of 1.0 mg/kg. Similar changes were caused by ADM at a daily dose of 0.25 to 1.0 mg/kg.(ABSTRACT TRUNCATED AT 400 WORDS)  相似文献   
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BACKGROUND: Although there is lymphatic flow into the popliteal fossa from a skin tumor located in the lower leg, popliteal metastasis is extremely rare. Recently, sentinel lymph nodes outside traditional nodal basins have been identified. This study investigated the incidence of sentinel nodes in the popliteal region and the indication for biopsy. METHODS: Fourteen patients with various skin cancers involving the lower extremities (nine melanomas, four squamous cell carcinomas, and one sweat gland carcinoma) underwent lymphoscintigraphy and excision with sentinel lymph node biopsy. RESULTS: In all 14 patients, hot spots showed accumulation in the groin region. Five of 14 patients (36%) demonstrated popliteal sentinel nodes in addition to the inguinal nodes. Three of five popliteal sentinel nodes were histologically studied. A patient with acral melanoma demonstrated micrometastasis of melanoma cells in a popliteal node but not in the groin node. CONCLUSION: This study demonstrates that sentinel lymph nodes located in the popliteal fossa are frequently detected by lymphoscintigraphy and that biopsy should be performed if popliteal nodes are identified.  相似文献   
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Antibodies to 3-methoxy-4-aminoazobenzene (3-MeO-AAB) and 2-methoxy-4-aminoazobenzene (2-MeO-AAB) DNA adducts were raised in rabbits against in vitro-adducted DNA samples. The enzyme-linked immunosorbent assay (ELISA) was used to determine the sensitivity and specificity of these antibodies. They proved highly specific for the modified DNA used as the immunogen, but cross-reacted with each other. Moreover, they showed cross reactivity with DNA modified by 4-( o -tolylazo)- o -toluidine, but not by other carcinogens, such as 4-aminobiphenyl or 4-nitroquinoline 1-oxide. The 50% inhibition level of antibody binding in the competitive ELISA was at 10–20 fmol of modified base per assay (equivalent to 1–2 adducts per 106 bases). Immunohistochemical staining indicated that these antibodies bind specifically to nuclear components of the liver in rats given either 3-MeO-AAB or 2-MeO-AAB at the dose of 50 mg/kg body weight.  相似文献   
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A new doxorubicin analogue, epirubicin (EPI), was evaluated in 41 patients with acute leukemia at 11 Japanese institutions participating in a phase II study between January 1983 and July 1985; during this period 35 patients were considered evaluable. There were 25 males and 10 females with a median age of 43 years (range, 19-71 years) and the median PS of 2 (range, 0-4). EPI was given to 25 patients who had previously been treated with intensive combination chemotherapy, of whom 22 had already received anthracyclines. Ten patients had not been treated previously. Two dose schedules were explored. The higher dose schedule (18 cases) consisted of the administration of 24 to 60 mg/m2 for 3 to 5 consecutive days, and the lower dose schedule (17 cases) consisted of 11 to 20 mg/m2 for 5 to 7 days. Remissions were obtained in 7 patients (20%), 2 of whom showed complete remission and 5 partial remission. The remission duration was 2, 2, 3, 5, 16, 16 and 29+ weeks, respectively. The expected myelosuppression was universal. Stomatitis occurred in 15 patients, of which 7 cases were severe. This stomatitis occurred frequently in the higher dose schedule, and was thought to be a dose-limiting factor. In others, alopecia, G.I. symptoms, and diarrhoea (4 patients) were seen. These results from a cooperative group study indicated that EPI was an effective drug for the treatment of acute leukemia.  相似文献   
9.
Elderly patients (aged greater than or equal to 65 years) with non-Hodgkin's lymphoma were treated either with CHOP or COP-BLAM therapy, and the effectiveness and reverse effects of COP-BLAM therapy were compared with those of CHOP therapy. Thirty-three patients (aged greater than or equal to 65 years) with previously untreated non-Hodgkin's lymphoma were entered either on CHOP or COP-BLAM regimen between September, 1979 and February 1990. To CHOP therapy was performed in 15 patients (median age; 70 years). Eight of them had diffuse large cell type lymphoma (large), five had diffuse medium-sized cell type (medium) and two had diffuse mixed cell type (mixed). As to clinical stage, there were patients in stage II, 4 in stage III and 9 in stage IV in CHOP group. Of 18 patients (median age; 68 years), who were treated with COP-BLAM therapy, 8 had of large lymphoma and 10 medium lymphomas in histopathological classification. In terms of clinical stage, there were 5 patients in stage II, 4 in stage III and 9 in stage IV. CHOP therapy and COP-BLAM therapy were performed according to the method reported by McKelvey et al, and by Laurence et al., respectively, using the full doses of drugs without consideration the age. Complete remission (CR) was achieved in seven (46.7%) of 15 patients treated with CHOP therapy. In this group, five (38.5%) of 13 patients in advanced stages (stage III or IV) entered CR. Of 18 patients subjected to COP-BLAM therapy, 15 (83.3%) achieved CR. Among 13 patients in advanced stage treated with COP-BLAM therapy, CR was achieved in 11 (84.6%).(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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