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91.
A 20-year-old woman with a primary angiosarcoma of the right atrium is reported. The patient had a cardiorespiratory arrest due to cardiac tamponade with bloody pericardial effusion. Magnetic resonance imaging (MRI) revealed a tumor, which was corroborated by selective coronary angiography. Open-heart surgery was performed. The tumor relapsed however, and she died four months after operation. The tumor was undetectable by echocardiography, but MRI demonstrated a heterogeneous mass with focal areas of high- and low-signal intensity in the right atrium, suggesting that MRI may allow characterization of cardiac tumors.  相似文献   
92.
93.
H Ogawa  T Hayama  Y Yamashita 《Brain research》1988,454(1-2):321-331
While stimulating the entire oral cavity of anesthetized rats, we recorded 3 types of neurons in the solitary tract nucleus; taste, mechanoreceptive and cold neurons. Most of the taste neurons were sensitive to thermal as well as to mechanical stimulations. Taste neurons predominantly sensitive to sucrose responded to warming and those most excited by NaCl or HCl were sensitive to cooling, and significant correlations were found between sucrose and warming and between NaCl and cooling. Most of the cold-sensitive taste neurons had receptive fields (RFs) at the anterior tongue and warm-sensitive taste neurons had whole or part of the RFs at the nasoincisor duct. About half the number of mechanoreceptive neurons were sensitive to cooling, producing phasic responses. RFs of some thermosensitive mechanoreceptive neurons and cold neurons were located. Warm-sensitive mechanoreceptive neurons or warm neurons were not evident. Therefore, interaction between thermal and taste sensations in the oral cavity probably takes place in the solitary tract nucleus, as well as in the chorda tympani.  相似文献   
94.
95.
The genetic differences between two types of dominant inherited myoclonus epilepsy, dentatorubral pallidoluysian atrophy (DRPLA) and benign adult familial myoclonus epilepsy (BAFME), have been reported. A gene with a CAG repeat expansion responsible for DRPLA has been isolated. We have examined CAG repeat expansion in the DRPLA gene in five BAFME families, and the abnormal CAG expansion was not observed in the affected subjects. Linkage analysis using DNA polymorphisms in the DRPLA gene and the genes for gamma-aminobutyric acid (GABA) receptor subunits, GABAR beta 1, GABAR beta 3, and GABAR alpha 6, showed that these genes were not responsible for BAFME.  相似文献   
96.
97.
We revealed morphology and physicochemical behavior of a widely used powerful hydrophilizing agent, polyvinylpyrrolidone (PVP), present on polysulfone (PS)/PVP films by atomic force microscopy (AFM). This is the first time such clear PS/PVP phase-separated morphology was observed by nanoscopic technique. The film surfaces were observed by the identical observation mode, probe and scanning conditions to reveal the change of PVP morphology and behavior between dry and wet conditions. Morphology was related to biocompatibility by combining AFM data with results of surface element composition, contact angle, adhesion amount of rabbit platelet and relative amount of adsorbed fibrinogen. PVP nano-particles of one or several molecules were formed on the dry PS/PVP film surfaces. Amount of PVP present on the surfaces increased with the molecular weight of PVP. At a mixed amount of 1-5 wt%, PVP K90 formed crowded particles on the dry surface. When wet, they swelled, followed by their union to produce a smooth surface leading to improved biocompatibility. The highest biocompatibility with excellent mechanical strength is achieved by blending the highest molecular weight PVP K90 at 1-5 wt%.  相似文献   
98.
Cryptogenic bilateral fibrosing pleuritis is a rare condition, and its pathogenesis and clinical course are poorly understood, with no established therapy available. A 61-year-old man presented with bilateral pleural thickening and lymphocytic exudative effusions. The patient was diagnosed with fibrosing pleuritis with no evidence of a known etiology on a surgical pleural biopsy. Within 16 months from the onset of respiratory symptoms, restrictive ventilatory impairment progressed rapidly, resulting in hypercapnic respiratory failure requiring home oxygen and non-invasive positive pressure ventilation therapies.  相似文献   
99.
BACKGROUND: We review the results of surgical radiofrequency ablation of both atria in patients of mitral valve disease approached by septal-superior exposure and discuss the availability of this approach. METHODS: Eighteen patients with a mean age of 65 years were included in this study. Thirteen patients had mitral valve regurgitation predominantly and five had mitral valve stenosis. Eleven patients underwent mitral valve plasty and valve replacement was carried out in seven. All ablation lesions were created on both atria using radiofrequency energy delivered by a unipolar malleable radiofrequency ablation catheter with seven electrodes at a minimum temperature of 80-85 degrees C for a period of 2 min. RESULTS: At the time of discharge, 14 patients were showed normal sinus rhythm and one patient remained in AF. The other three patients were free from atrial fibrillation; however, they received dual-mode, dual-pacing, dual-sensing pacemaker implantation because of bradycardia during the early postoperative phase. At a mean time of 7 months after surgery, all patients were free from atrial fibrillation; 13 patients showed normal sinus rhythm and five patients received dual-mode, dual-pacing, dual-sensing pacemakers. CONCLUSION: Septal-superior exposure provides an excellent operative view both for mitral valve surgery and for radiofrequency ablation. However, this exposure has not been considered a first-line approach because of the high rate of pacemaker implantation.  相似文献   
100.
Summary The ability of T cells to secrete IL-2 in patients with systemic lupus erythematosus (SLE) was investigated. In patients with SLE, impaired IL-2 production by peripheral blood lymphocytes stimulated with mitogens is well known. In this paper, we report that purified T cells stimulated with mitogens, in the presence of Epstein-Barr virus transformed B cells (B-LCL) as an accessory cell, however, could secrete a large quantity of IL-2 as much as normal T cells. In order to study this potential capacity of T cells to secrete IL-2 in patients with SLE, IL-2 secreting T cells were examined. To obtain these cells, T cells were divided into cluster forming cells and noncluster forming cells after short culture of T cells with accessory cells in the presence of Con A. Then the ability of IL-2 production in two kinds of separated T cells was examined. We found that 1) after short culture with B-LCL, the cluster forming T cells could secrete IL-2 when cultured again, but noncluster forming T cells could not, even in the presence of B-LCL, 2) after short culture with macrophages, in normal donors and SLE patients, noncluster forming T cells were able to secrete a greater amount of IL-2 than cluster forming and undivided T cells when cultured with B-LCL. These results suggested that IL-2 secreting T cells activated with Con A in the presence of macrophages were shown to be not all of, but a part of them, and that in SLE T cells which secreted IL-2 in the presence of macrophages might be impaired but other IL-2 secreting T cells might remain intact.  相似文献   
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