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51.
To evaluate the clinical significance of scintigraphic overlap of thallium-201 (201T1) and technetium-99m pyrophosphate (99mTc), we observed 28 patients with acute myocardial infarction (AMI) in whom coronary reperfusion was attempted. All patients underwent dual energy emission computed tomography (D-ECT) on the third post AMI day which facilitated comparing 99mTc and 201T1 images from identical slices simultaneously. The scintigraphic results of the 28 patients were as follows: (table, see text) In conclusion, (1) significant 201T1 and 99mTc overlap on D-ECT suggest very early and successful reperfusion, and (2) none of the patients with unsuccessful reperfusion exhibits overlap.  相似文献   
52.
Thrombotic microangiopathy (TMA) may develop after living donor liver transplantation (LDLT), but the mechanism is not fully understood. We retrospectively analyzed all patients undergoing LDLT at our center, including TMA patients, to elucidate the clinical characteristics and presentation and to determine which patients have a higher risk of occurrence of TMA. In all, 57 adult patients were reviewed after LDLT at our institution. TMA was diagnosed by sudden and severe thrombocytopenia, followed by hemolytic anemia with fractionated erythrocytes in the blood smear. Clinical features were compared between the TMA group and the non-TMA group. Of the 57 patients, 4 were diagnosed with posttransplantation TMA. ABO blood group (ABO)-incompatibility, cyclophosphamide (CPA), and recipient blood group (type O) were closely correlated with the occurrence of TMA. Thrombocytopenia appeared 1 to 5 days before hemolytic anemia. Coagulative function markers stayed at the same level after TMA, while marked elevation was shown in fibrinolytic function markers such as plasminogen activator inhibitor type 1 (PAI-1). TMA occurred at a higher prevalence in ABO-incompatible graft recipients. Additional factors associated with ABO-incompatible transplantation, such as an overdose of immunosuppressants, may affect the likelihood of TMA. Sudden and severe thrombocytopenia presented before hemolytic anemia and the serum levels of PAI-1 correlated well with the clinical course of TMA. In conclusion, early recognition of thrombocytopenia and elevation of PAI-1 is crucial to diagnose TMA especially in ABO-incompatible LDLT.  相似文献   
53.
Hypertrophic scars (HS) are a consequence of abnormal wound healing. We examined fatty acids that are contained within, and participate in, every reaction through the membrane; then, we analyzed the percentage composition of the fatty acids in deepithelialized normal dermis (ND) and HS. In vivo HS samples were obtained from six patients undergoing surgical excision, and ND samples from five patients undergoing skin grafting surgery for excess. In vitro, cultured fibroblasts from HS and ND were also analyzed. The percentage composition of fatty acids extracted from all the samples was analyzed. In vivo, arachidonic acid (20:4) was significantly more abundant in HS than in ND, in the phospholipids from both whole tissue and cell membranes. In vitro, there were no significant differences among ND, HS, and 10% fetal calf serum. The results suggest that HS formation does not necessarily involve simple excess of 20:4; however, there are considerable differences in the percentage composition of 20:4 between ND and HS. Arachidonic acid probably participates in the formation and maintenance of HS, whereas in vitro cultured fibroblasts are affected largely by fetal calf serum.  相似文献   
54.
Using 4 and 8-channel super-parallel magnetic resonance (MR) microscopes with a horizontal bore 2.34T superconducting magnet developed for 3-dimensional MR microscopy of the large Kyoto Collection of Human Embryos, we acquired T(1)-weighted 3D images of 1204 embryos at a spatial resolution of (40 microm)(3) to (150 microm)(3) in about 2 years. Similarity of image contrast between the T(1)-weighted images and stained anatomical sections indicated that T(1)-weighted 3D images could be used for an anatomical 3D image database for human embryology.  相似文献   
55.
BACKGROUND: Our recent study showed that granulocyte-colony stimulating factor (G-CSF) promoted bone-marrow cells (BMC) to migrate into the infarcted heart and that they differentiated into cardiomyocytes. However, we still do not know to what degree bone-marrow-derived cardiomyocytes contribute to myocardial regeneration after injury. In this study, we verified the proportional contribution of cells from bone marrow (BM) and from non-bone marrow (n-BM) in regenerating neomyocardium after myocardial infarction. METHODS: Eight C57BL/6 mice were irradiated (900 cGy), and green fluorescent protein (GFP) mouse-derived BMCs (GFP-BMC, 1 x 10(6) cells) were injected. Four weeks later, the left descending coronary artery was ligated. Recombinant human G-CSF (200 microg/kg/day, 8 days) was injected. At 4 weeks after ligation, hearts were fixed for histology. We calculated the proportions of cardiomyocytes derived from BM and n-BM after taking the chimeric rate into consideration. RESULTS: The chimeric rate was 54.6% +/- 5.9%. At the infarcted border area, the total cell number was 1000.3 +/- 56.5/mm(2), and mobilized BM-derived GFP-BMC was 103.3 +/- 13.1/mm(2). After compensation with the chimeric rate, we found BM-derived troponin I-positive cells at 23.9 +/- 4.1/mm(2), nestin-positive cells at 12.9 +/- 2.6/mm(2), and Ki67-positive cells at 18.3 +/- 2.6/mm(2), respectively. We found significant differences in the contribution of troponin I-(6.7% +/- 1.7% vs 93.3% +/- 1.7%), nestin- (2.4 +/- 0.5 vs 97.6 +/- 0.5), and Ki67-positive (3.9 +/- 1.0 vs 96.1 +/- 1.0) cells derived from BM and n-BM. CONCLUSIONS: Bone marrow was one of the origins of regenerated cardiomyocytes; however, the contribution of cells from BM was very small compared with those of n-BM origin in the infarction model.  相似文献   
56.
Conclusions  Reduced utilization of fatty acids at rest often is observed in severely ischemic myocardium and possibly postischemic myocardium despite normal perfusion at rest. The role of metabolic imaging in identifying postischemic insult as ischemic memory imaging has been the focus of recent investigations. A number of reports from Japan show quite acceptable diagnostic accuracy of BMIPP imaging for detecting coronary patients without prior MI. In addition, recent data indicate that BMIPP imaging has prognostic value when applied in patients with documented or suspected coronary disease. The major advantage of BMIPP imaging is to demonstrate ischemic myocardium as an area of altered metabolism at rest. Thus this study is of clinical importance for elderly patients or for patients not suitable for a stress study. Furthermore, this radiopharmaceutical tracer may hold promise in demonstrating early alteration of energy metabolism in a variety of myocardial disorders.  相似文献   
57.
The purpose of this study was to evaluate the acute effects of corticosteroid and iodide preoperative therapy in patients with Graves' disease in terms of thyroid function and immunological parameters. The above combination was prescribed for 4 patients who had experienced severe side effects from antithyroid drugs (ATD) in order to reduce the possibility of post-thyroidectomy thyroid storm. Corticosteroids were employed daily for four days, and iodides were given daily for two weeks prior to thyroidectomy. The free T3 values decreased rapidly to euthyroid levels following the administration of both drugs, although the free T4 values were still much higher than normal in 3 of the 4 patients at the time of surgery. By comparison, 3 of 8 patients treated with ATD also had thyroid hormone levels above normal. Studies of lymphocyte subsets revealed that the percentage of helper T cells was significantly less in the corticosteroidiodide treatment group than in the control and ATD groups. It is thus possible that postoperative thyroid storm might be prevented through corticosteroid-iodide therapy by virtue of the reduction of free T3 values to within the normal range by the time of surgery. The acute suppression of helper T cells was another result of this form of therapy observed.  相似文献   
58.
The relationship between dose intensity of cytotoxic agents and therapeutic results was examined in a retrospective analysis of 32 patients with non-metastatic high-grade osteosarcoma of the extremities. The average dose intensities of individual agents were 9.8 mg/m2/week for doxorubicin, 1.2 g/m2/week for methotrexate, and 10.5 mg/m2/week for cisplatinum. The dose intensities of doxorubicin and methotrexate were significantly correlated with the clinical results, while that of cisplatinum was not. These results indicate that maximal dose intensification of doxorubicin and methotrexate is an important determinant of treatment outcome for patients with osteosarcoma.  相似文献   
59.
A 41-year-old man was hospitalized for further evaluation of an abnormal chest films which revealed a nodular shadow in the right middle lung field, which remarkably enlarged during one year. As no diagnostic procedures ruled out lung carcinoma of right S6, a right lower lobectomy was performed. Pathologically the nodules were composed of amorphous and eosionphilic materials which were diagnosed as amyloid by Congo-red stain and electron microscopic examination. Since there were no deposits in other organs and there was no abnormality of serologic and urinary protein analysis, a diagnosis of primary nodular pulmonary amyloidosis was established.  相似文献   
60.
Four symptoms of sequelae (abnormal synkinesis, facial spasm, contracture, and crocodile's tear) which persisted or appeared after 6 months from onset were examined with 351 patients with Bell's palsy. The incidence of sequelae were 2% in the group having score (May-Hosomi's modified method, 90 points method) over 40 points within 1 months after onset. Other hand, the incidence of sequelae were 15% in the group having score under 40 points at 1 weeks from onset, 30% in the group having score under 40 points at 2 weeks, 57% in the group having score under 40 points at 3 weeks, and 76% in the group having score under 40 points at 1 month. From these findings, it was seen that the prognostication with a high accuracy was possible by the score.  相似文献   
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