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991.
Y Nishiya M Fujimura M Toshima H Noto T Ishikawa A Miwa H Watanabe N Takayanagi 《Kyobu geka. The Japanese journal of thoracic surgery》1999,52(11):954-957
Tricuspid regurgitation is often seen but is rarely categorized as "idiopathic". A 66-year-old man suspected of idiopathic tricuspid regurgitation underwent tricuspid valve replacement. With right heart failure over twenty years, his CTR increased to eighty six (86) per cent. During operation, no abnormal findings were observed except for the dilated tricuspid valve ring. Then a stented porcine xenograft (Carpentier-Edwards 33 mm) was inserted in the tricuspid valve annulus. Seven years after replacement, he died. Autopsy demonstrated myocardial hypertrophy of the right ventricle and dilatation of the right heart, supporting the diagnosis of idiopathic tricuspid regurgitation. 相似文献
992.
Brain temperature modifies glutamate neurotoxicity in vivo 总被引:5,自引:0,他引:5
The purpose of this study was to examine the effects of mild hypothermia and hyperthermia on glutamate excitotoxicity. Glutamate-induced cortical lesions were produced in hypothermic (32 degrees C), normothermic (37 degrees C), and hyperthermic (40 degrees C) rats by perfusion of a 0.5 M glutamate solution via a microdialysis probe. The volume of the lesion 7 days after glutamate perfusion was quantified histologically by image analysis. This histological assessment was performed in two experiments; in one, each of the target temperatures was induced before glutamate perfusion, and in the other, each of the target temperatures was induced after stopping the glutamate perfusion. We also examined the effect of temperature on the diffusion of exogenously delivered material in the extracellular space using autoradiography of the perfused glutamate solution containing 14C-labeled sucrose. In the two experiments in which each of the target temperatures was induced before or after glutamate perfusion, the volume of damage was reduced by mild hypothermia and enlarged by mild hyperthermia. The volume of 14C diffusion also increased as brain temperature increased. These results provide evidence that small variations of brain temperature modify glutamate excitotoxicity. The results also suggest that the change in glutamate diffusion in the extracellular space is one mechanism by which mild hypothermia and hyperthermia exert their protective and harmful effects respectively. 相似文献
993.
Miyagi M Sakai K Hasegawa A Ohara T Mizuiri S Aikawa A Hadano T Nakano H Shindo M Ishikawa Y Hasegawa C Hirayama N Arai K 《Clinical transplantation》1999,13(Z1):43-47
A 41-yr-old patient with non-insulin-dependent diabetes mellitus (NIDDM), before and after ABO-incompatible renal transplant, is reviewed using serial protocol biopsy. Although she recovered from delayed hyperacute rejection (DHAR) immediately post-transplantation, her graft function deteriorated gradually. A mild acute transplant glomerulitis, noted at the 155th day post-transplantation, progressed to pronounced chronic transplant glomerulopathy over 5 yr. In the specimen of the last biopsy, at 5 yr post-transplantation, glomeruli demonstrated an exudative hyaline lesion, which was characteristic of diabetic nephropathy in addition to chronic transplant glomerulopathy. Therefore, we made a diagnosis of this glomerular lesion as chronic transplant glomerulopathy complicated by diabetic glomerulopathy. Considering the result of this case, the protocol biopsy is a useful procedure to diagnose an accurate cause of graft dysfunction in individual cases. It is concluded that the protocol biopsy is apparently useful for the detection of various pathological processes occurring in allograft and may contribute to a strategy for improvement of graft survival. 相似文献
994.
Antonio G. Carrizo 《Critical Reviews in Neurosurgery》1999,9(2):79-86
Female gender and cigarette smoking appear to be risk factors for the development of multiple intracranial aneurysms. An acquired nature is likely in this form. The mechanism of aneurysm formation in patients with sickle cell anemia is apparently different. These patients also present multiple aneurysms that show propensity for vertebrobasilar territory and appear at a younger age. Familial cerebral aneurysms are diagnosed once heritable connective tissue disorders have been excluded. The age of patients tends to be lower and the size of aneurysm to be smaller at the time of rupture in the familial form. These aneurysms are less frequently found in the anterior communicating artery than the sporadic aneurysms. A high incidence of asymptomatic familial aneurysms was detected in people with family histories of intracranial aneurysms studied by means of magnetic resonance angiography. Furthermore, familial aneurysms are more likely to rupture in families having members with aneurysmal subarachnoid hemorrhage (SAH) than in those without. The results of an interesting study using color "power" transcranial Doppler ultrasound in patients with aneurysmal SAH suggest that as the intracranial pressure diminished, the size of the aneurysm increased, and there was relatively little change between maximum and minimum dimensions during the cardiac cycle, i.e., the pulsatility is reduced. The use of postoperative angiography after clipping is a matter of debate. The indication more widely accepted is in large aneurysms with a wide neck, in which incomplete clipping can be suspected. Taking into account the current low risk of angiography in centers of excellence, its routine use may be recommended. Aneurysm remnants, vessel occlusion, vasospasm, and newly identified aneurysms are the main findings that were reported. 相似文献
995.
A 45-year-old male was admitted to our hospital for investigation of a nodular shadow in segment 5 of the right lung on a
chest computed tomogram. A right middle lobectomy with mediastinal lymph node dissection was performed under a diagnosis of
lung cancer, and histologic examination confirmed small cell carcinoma. There were sarcoid reactions in the resected lymph
nodes and the lung parenchyma, but no signs of systemic sarcoidosis were evident. Sarcoid reactions are rarely observed in
the regional lymph nodes draining malignant tumors. Moreover, while they are most common in squamous cell carcinoma of the
lung, they extremely rare in small cell carcinoma. To our knowledge, this is only the third report of this unusual entity
in the English and Japanese literature. 相似文献
996.
Ove Almkvist Bengt Winblad 《European archives of psychiatry and clinical neuroscience》1999,249(3):S3-S9
Alzheimer’s disease (AD) is common in elderly individuals; it causes distress for the patients and their relatives as well as large costs for the society. With the advent of symptomatic treatment at present and probable etiology-based cures in the future, it will be possible to relieve and put an end to these negative effects. Therefore, it is necessary to diagnose the disease as early as possible. In this review, we briefly summarize the state-of-the-art concerning various available clinical and biochemical methods for identifying AD. Increasing age, heritage, and presence of ApoE e4 allele have been confirmed as risk factors for AD as well as some putative factors (e.g., low education, hypertension, hypotension) based on epidemiological recent research. Selective impairment of episodic memory has been found to be a preclinical marker for future development of AD based on convergent data from asymptomatic AD-related mutation carriers, longitudinal studies of patients with mild cognitive impairment (MCI), and epidemiological studies of incident AD cases. Neurophysiological methods are inexpensive and useful for the identification of changes in brain dysfunction in AD and new promising methods are under development. Using magnetic resonance imaging (MRT), structural measurements of brain atrophy and specific brain structures such as the hippocampus have been reported to detect dementia development early in the course of disease. Similarly, functional measurements of brain activity (e.g., blood flow) have revealed that hypometabolism in bilateral parietotemporal brain areas early in the disease course. Finally, biochemical studies have demonstrated that certain proteins (e.g., tau the Aβ1-42/43 metabolite of the amyloid precursor protein) may be associated with the disease process in AD, although the specificity of these markers remains to be established. It is concluded that still no single marker of AD exists, which makes it necessary to rely on data from multiple sources in order to arrive at the best possible diagnosis of AD. 相似文献
997.
998.
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1000.
Long-term outcome of coronary events in hemodialysis patients younger and older than 65 years of age 总被引:1,自引:0,他引:1
Hase H Joki N Saijyo T Fukazawa M Ishikawa H Tanaka Y Imamura Y Nakamura R Nakamura M Yamaguchi T 《Nihon Jinzo Gakkai shi》1999,41(8):747-753
BACKGROUND AND AIM: It has been reported that a coronary event is the leading cause of mortality in HD patients. The aim of this study was to examine and compare prospectively the effect of aging in relation to the in-hospital and the long-term outcome in HD patients with or without revascularization therapy who had experienced a coronary event. STUDY PATIENTS AND METHODS: Seventy consecutive HD patients with coronary events (9 AMI, 48 AP, and 13 CHF) were registered in this study and 69 patients underwent CAG. Patients were classified into elderly (> or = 65, n = 33) and younger (< 65, n = 37) groups based on their ages at the time of the events. Forty-six patients (21 vs 25) underwent initial coronary revascularization therapy. We followed 70 HD patients with coronary events for a mean period of 31 +/- 21 months (range: 1 day to 77 months). RESULTS: A level of 64% of the elderly group and 41% of the younger group experienced coronary events within the first year of HD. The diseased vessels (2.2 vs 1.9 per patient) and stenotic lesions (2.8 vs 2.5 pre patients) were not significantly different between the two groups. The 70-month survival rate was significantly lower (21% vs 65%, p = 0.0423) in the elderly group than in the younger group. The complicated rate of stroke after a major event was significantly higher (14 vs 4, p = 0.0025) in the elderly group than in the younger group. Moreover 21 elderly patients (11 cardiac death, 5 stroke, 4 cancer) and 9 younger patients (8 cardiac death, 1 stroke) died during the 70-month follow-up period. CONCLUSIONS: Coronary events were most frequent in the first year of HD. Long-term survival rate was significantly lower in elderly patients than in younger patients. Cardiac death was the most common cause of death in both groups regardless of performing coronary revascularization. Death due to stroke and cancer was also more common in elderly patients. 相似文献