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21.
Twenty eight patients with native valve endocarditis (NVE) were subjected to this study. Thirteen patients underwent an operation at the chronic phase, and 15 patients at the active phase. One of the 13 patients at the chronic phase died of cardiac rupture due to myocardial infarction which had occurred preoperatively, and one of 10 patients at active phase without annular infection died of rupture of mycotic cerebral aneurysm early postoperatively. Among 5 patients at the active phase with annular infection, prosthetic valve endocarditis occurred in one patient 1.5 months after supraannular aortic valve replacement, and the second operation with a translocation technique was needed. This patient was lost from low output syndrome. Another patient in this group, who underwent a translocation technique because of mycotic annular abscess, died of intestinal infarction late postoperatively. The other 24 patients went a good postoperative course. Five patients with annular infection at the active phase had a shorter duration from the infectious onset to operation (20 days to 2 months, average 38 days), and the causative microorganisms were streptococcus faecalis, staphylococcus epidermidis and gram-negative coccus. One patient, who died of mycotic cerebral aneurysmal rupture, had candida albicans as a causative microorganism. For patients with NVE, an early aggressive operation is essential before infection extends to the annulus or to other vital organs, especially when these microorganisms are identified.  相似文献   
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23.
To determine the relative superiority of a prosthesis in the mitral position, in vivo hemodynamics were examined by Doppler echocardiography, and the results were compared with other types of mechanical mitral valves including 63 Bj?rk-Shiley convexo-concave (BS) values, 30 Duromedics (DM) valves, and 58 Medtronic Hall (MH) valves. For this comparison, the following indices were evaluated: peak velocity of mitral flow (PV), mitral valve orifice area (MVA), mitral valvular regurgitation, New York Heart Association (NYHA) classification, pulmonary capillary wedge pressure (PC), cardiac index (CI) and valve-related complications. On Doppler echocardiograms, PV ranged from 1.2 to 2.0 m/sec with a mean of 1.6 m/sec. There was no evident relationship between the PV and the valve size in each type of prosthesis, and no significant difference in the PVs among the valves. The mean MVA was 2.6 cm2 (25 mm DM, 25 mm MH), which was regarded satisfactory from a clinical standpoint. MVA increased with the increase in the valve size in all types of valves, and of all sizes, MVA was larger in the DM and MH groups than in the BS group. Similarly, the incidence of valvular regurgitation was relatively low in all groups, and the degree of regurgitation proved to be grade II or less in all cases. As for the clinical results, clinical symptoms (NYHA) and hemodynamic states (PC, CI) improved postoperatively, with the differences among the types of prosthetic valves being insignificant. The incidences of thromboembolism, valvular thrombosis, valve failure and prosthetic endocarditis were relatively low in all groups.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
24.
The purpose of this study was to determine whether the late component of somatosensory evoked potentials (SEP) induced by electrical tooth stimulation and pain intensity are inhibited by heterotopic ischemic stimulation. The tourniquet pressure with 50 mmHg greater than the individual's systolic pressure was applied to the left upper arm for 10 min as ischemic conditioning stimulation. The late component of SEP and visual analogue scale (VAS) were recorded at 4 times and both were significantly decreased when ischemic conditioning stimulation was applied. The maximum reductions in SEP amplitude and the VAS value were 26.1% and 21.2%, respectively, during ischemic conditioning stimulation. After-effect was observed 5 min after removal of the conditioning stimulation. The present study revealed that heterotopic ischemic stimulation attenuated the late component of SEP induced by electrical tooth stimulation, triggering diffuse noxious inhibitory controls (DNIC) and after-effects in the trigeminal nerve territory. It was also suggested that the DNIC effect differs, depending on the intensity, kind, and quality of the test and conditioning stimuli.  相似文献   
25.
26.
A 57-year-old man with a history of renal cell carcinoma presented with presyncope. He underwent nephrectomy years earlier followed by HLA-matched allogeneic peripheral-blood stem-cell transplantation. Echocardiographic investigation revealed a solitary right ventricle mass without contiguous vena caval or right atrial involvement. The mass was pathologically confirmed to be metastatic carcinoma in the right ventricular cavity. This case highlights the need to consider an underlying neoplastic syndrome in patients presenting isolated right ventricle mass by echocardiography.  相似文献   
27.
We report a patient manifesting seizures with bilateral symmetric tonic posturing, which were markedly reduced after resection of the left precuneus. A 16-year-old man had sudden onset, complex partial seizures with bilateral symmetric tonic posturing since the age of eight years. Magnetic resonance fluid-attenuated inversion-recovery imaging revealed a hyperintense lesion in left precuneus. In almost all focal seizures recorded during an invasive EEG evaluation, ictal onset was detected from the inferomesial aspect of the lesion, but fast paroxysmal discharges from the ipsilateral supplementary motor area (SMA) were observed just before the clinical onset. After surgical excision of the EEG onset zone, including the lesion, seizure frequency was markedly (> 95%) reduced. By the 20th month after surgery, there were only brief nocturnal seizures involving slight elevation of both shoulders and slight abduction of both arms, with preservation of consciousness occurring once every few days. Invasive EEG findings and surgical outcome suggested that the epileptic activity originating from the epileptogenic zone may have propagated to the symptomatogenic zone including mainly the ipsilateral SMA. In summary, we report an interesting case of bilateral symmetric tonic posturing suggesting propagation to the SMA. MRI and invasive EEG confirmed the epileptogenic focus as a precuneate cortical dysplasia lesion.[Published with video sequences].  相似文献   
28.
A 61-year-old man had been treated for malignant fibrous histiocytoma with the pulmonary and the lymph node metastasis in the department of orthopedics in our hospital. He was admitted to our department because of an acute onset of conscious disturbance and non-fluent aphasia. Diffusion-weighted imaging (DWI) showed high signal intensity areas in the bilateral cerebella, thalami and posterior lobes. T2WI did not show any mass effects. Enhanced CT did not reveal any enhanced lesion. He was diagnosed as having cerebral embolism, and his conscious disturbance was improved after medication. Eight weeks later, he presented dysphagia, dysarthria, and ataxia in his extremities. DWI showed multiple lesions of low signal intensity located at the identical place where had showed high signal intensity in the initial DWI. T2WI showed high signal intensity area with mass effect. It was indicated that cerebral metastasis might grow after tumorgenic embolism. This is a rare case that tumor emboluses were developed to the metastatic brain tumors.  相似文献   
29.
Progressive multifocal leukoencephalopathy (PML) is a fetal demyelinating disease in the central nervous system. PML was once a rare disease, but it is now relatively common among AIDS (acquired immunodeficiency syndrome) patients. The immunological state of patients mainly contributes to the pathogenesis of PML. Genetic changes of the etiological agent, however, may also be involved in the development and progression of the disease. The major genetic changes possibly associated with PML include the regulatory region rearrangement and the VP1 loop mutation. Both changes have been identified as genetic changes usually occurring in JCV (JCvirus) DNAs from the brain and cerebrospinal fluid of PML patients. Although it remained to be clarified how these changes are involved in the pathogenesis of PML, accumulating evidence suggests that the VP1 loop mutation is associated with the progression of PML. Here we overview studies (mainly those performed by ourselves) on these genetic changes.  相似文献   
30.
AE0047, a novel calcium antagonist, has mild and long-acting hypotensive effects. This drug also has more selective dilating action on cerebral arteries than on other systemic ones. We studied the cerebral vasodilatative effects of AE0047 by means of vertebral angiography in anesthetized dogs. Vertebral blood flow (VBF) was significantly increased by 91, 139 and 132% in 10, 30 and 60 min after intravenous administration of AE0047 at 30 micrograms/kg, respectively. No difference in vasodilating action was observed among basilar, posterior communicating, middle cerebral and internal carotid arteries. In basilar artery, the dilatative rate was about 30% between 10 and 60 min after injection of AE0047. Following intravertebral administration of endothelin at 100 pmol/kg, small vessels of the cerebral artery were constricted, and VBF was gradually decreased. AE0047 eliminated the vasoconstriction and increased VBF. Moreover, the vasoconstrictive effect of endothelin was prevented by pre-treatment of AE0047. These results indicate that AE0047 has potent vasodilating and spasmolytic actions on cerebral arteries.  相似文献   
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