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1.
Nobuhiko Joki Hiroki Hase Yuri Tanaka Yasunori Takahashi Tomokatsu Saijyo Hiroyaou Ishikawa Yoji Inishi Yoshihiko Imamura Hisao Hara Taro Tsunoda Masato Nakamura 《Nephrology, dialysis, transplantation》2006,21(6):1633-1639
BACKGROUND: In patients with chronic kidney disease (CKD), although strong associations have been observed between malnutrition and atherosclerosis, the relationship between serum albumin concentration and angiographic changes of coronary artery disease (CAD) remains poorly explored. The goal of the present study was, in patients with CKD, to clarify the relationship between the angiographic severity of CAD and serum albumin concentration reflecting either inflammation or nutrition or both. METHODS: In this study, 100 end-stage renal disease (ESRD) patients were enrolled, who commenced long-term dialysis therapy at our hospital and underwent coronary angiography within 3 months of the first haemodialysis (HD) session. Mean age was 63+/-11 years, 20% of the subjects were female and 62% had diabetes. Severity of CAD was evaluated in terms of (i) number of vessels exhibiting CAD (>or=75% stenosis) and (ii) Gensini score (GS). Clinical characteristics and laboratory findings were recorded at initiation of long-term HD therapy. We then evaluated a possible association with the presence and degree of CAD. RESULTS: Sixty-four patients exhibited signs of CAD. Forty-one among them (64%) had multivessel disease. On univariate logistic regression analysis, age, diabetes and hypoalbuminaemia were significantly associated with multivessel CAD. Univariate linear regression analysis demonstrated a positive correlation of age and diabetes with GS, and an inverse correlation of BMI and serum albumin level with GS. Stepwise regression analysis showed age and serum albumin level to be independently associated with multivessel CAD and GS. The ROC curves demonstrated best cut-off levels of age and albumin for predicting multivessel CAD to be 70 years and 3.15 g/dl, respectively. CONCLUSION: Hypoalbuminaemia at the initiation of dialysis is an important predictor of advanced CAD, particularly in male and in diabetic patients. It may reflect mainly a state of inflammation. However, malnutrition as a confounding factor cannot be entirely excluded. 相似文献
2.
Toru Takahashi Yutaka Hasegawa Kiyohiro Ohshima Taro Nameki Yasuo Morishita 《Annals of thoracic and cardiovascular surgery》2005,11(4):245-248
Although aortic valve replacement (AVR) is an effective treatment for patients with aortic valvular disease, the implantation of a small aortic prosthesis may result in residual left ventricular outflow stenosis and transvalvular gradient. In this study, the outcome in the long-term period of patients treated with a small aortic prosthesis was analyzed retrospectively. Twenty-four patients with AVR were divided into two groups, group A and group B. Group A consisted of 16 patients with 21 mm-sized prosthetic valves, and group B consisted of 8 patients with 19 or 16 mm-sized prosthetic valves. There were no significant differences in preoperative cardiac function or operative procedure in the two groups. The mean follow-up period (months) was 55.0 in group A and 51.3 in group B. RESULTS: One patient died of cerebral infarction in group A. There were no significant differences in cardiothoracic ratio (CTR), left ventricular ejection fraction (LVEF), and left ventricular mass index (LVMI) between the two groups. Postoperative physical activity according to the New York Heart Association (NYHA) classification showed no significant differences in the two groups. Despite using a small prostheses for AVR, the postoperative course was good in the long-term period, although careful follow-up is necessary. 相似文献
3.
4.
Solitary fibrous tumors (SFT) have recently been established to be of mesenchymal origin. Although there are numerous reports
of SFTs arising from the pleura, reports of the tumor arising from extrapleural sites are comparatively rare [Fletcher CDM,
Unni K, Mertens F (eds) World Health Organization classification of tumors, pathology & genetics, tumors of soft tissue and bone. IARC Press, Lyon, pp 86–901, 2002]. We report a case of SFT arising in the inguinal region. 相似文献
5.
Kazumichi Yamada Satoshi Goto Taro Oyama Makoto Yoshikawa Shinji Nagahiro Yukitaka Ushio 《Acta neuropathologica》1995,89(2):172-177
The present study concerns the vulnerability of striatal interneurons immunopositive for the Ca2+-binding protein calretinin to ischemic neuronal injury. An immunohistochemical study was carried out on the striata of rats which had undergone transient middle cerebral artery occlusion. Two weeks after the ischemia, there was a marked reduction in the number of calretinin-positive neurons in the ipsilateral ischemic lesion, although the striatal interneurons positive for parvalbumin, which are a neuronal population distinct from the calretinin-immunoreactive cells in the striatum, were spared in the insulted areas. The present data indicate that the striatal calretinin-positive neurons are less resistant to transient ischemia, suggesting that there may exist vulnerability differences among the striatal interneurons in ischemia-induced neuronal injury. 相似文献
6.
Neurotoxic effects of flunarizine (Fz), a selective calcium channel blocker, on the nigrostriatal dopamine system was investigated. Systemic injections of Fz to mice resulted in a transient loss of tyrosine hydroxylase (TH) immunoreactive nigrostriatal neurons without cell loss. TH immunoreactivity in these neurons was greatly reduced as rapidly as one day after drug administration (regardless of dosage used) and thereafter recovered in both dose- and time-dependent manners. Such a novel neurotoxic action of Fz may constitute a morphological substrate for reversible drug-induced parkinsonian signs described in recent clinical case reports. 相似文献
7.
H Hirai K Yamasaki H Kidena M Kono 《Kaku igaku. The Japanese journal of nuclear medicine》1992,29(12):1447-1454
In vivo sodium concentrations in the normal brain tissue and a tumorous tissue were analyzed using MR Na image. The nuclear magnetic resonance enabled us to divide the signal from sodium in the living tissue into 2 parts based on the differences of T2 value. Those are fast component having the T2 value of less than 5 msec and slow component of 15-40 msec. We investigated the effect of macromolecules on T2 value of sodium image using polyvinyl alcohol (PVA) powder. MR Na image was taken with the parameters of TR/TD, 110 ms/1.9 ms (FID image) and TR/TE, 110 ms/20 ms (SE image). Saline solution showed high intensity on both FID image and SE image. Saline solution added PVA (PVA phantom) also showed high intensity on FID image, whereas the signal intensity of PVA phantom in SE image extinguished. To know the relation between the signal intensity and sodium concentration, sodium concentration--signal intensity curve was obtained using phantoms with various sodium concentrations (0.05-1.0%). This curve showed a direct proportion between sodium concentration and signal intensity on Na image. We measured further the sodium concentrations of the human brain tissue. Sodium phantoms were arranged around the heads and the MR Na images of the normal brains from 3 volunteers and a patient with a brain tumor (meningioma) were taken. The sodium concentrations of occipital lobe, basal ganglia and the tumorous tissue were calculated using the sodium concentration--signal intensity curve obtained from the phantoms arranged around the heads.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
8.
OBJECTIVE: The purpose of this study was to characterize the etching behavior of titanium in concentrated sulfuric acid and discuss its application on surface modification of titanium for biological use. METHODS: Commercially pure titanium (cpTi) plate was etched in 48% H2SO4 at RT -90 degrees C for 0.25-8 h. The weight loss was derived from the weight differences before and after etching. The surfaces after etching were characterized by surface roughness, X-ray diffractometry, and scannning electron spectroscopy. The apparent activation energy of the dissolution of cpTi into acid was derived from an Arrhenius plot of the rate of weight loss versus the acid temperature. RESULTS: The surface roughness of cpTi increased with the acid temperature and etching time. The surface roughness was strongly related to the weight loss. The weight loss increased drastically with the acid temperature after an initial period, which shortened with increasing acid temperature. The apparent activation energy for the dissolution of cpTi in H2SO4 was derived as 67.8 kJ/mol. SIGNIFICANCE: This study indicates that etching with concentrated sulfuric acid is an effective way to modify the surface of titanium for biological applications. 相似文献
9.
The purpose of this study was to determine the effect of pulsatile flow on cerebral perfusion under cardiopulmonary bypass (CPB). Twenty-three patients who underwent cardiac operations were divided into two comparable groups: Group A (N = 11) had standard nonpulsatile flow, while in Group B (N = 12), a pulsatile pump was used. The blood flow of left common carotid artery and radial arterial pressure were continuously monitored during cardiac operation in both groups and cerebral vascular resistance was calculated. In Group B, the perfusion pressure of left common carotid artery was monitored and compared with that of radial artery. Arterial and internal jugular venous blood were sampled and the difference of cerebral A.V O2 contents and cerebral oxygen consumption was calculated. Cerebral vascular resistance in Group B (54.0 +/- 11.2% of the value of before-CPB) significantly decreased compared to that in Group A (72.2 +/- 11%) at the end of CPB (p less than 0.05). Pulse pressure following pulsatile CPB flow was 15.1 +/- 5.8 mmHg monitored in radial artery and it reduced to 8.5 +/- 5 mmHg in left common carotid artery. Although there was no significant difference in cerebral oxygen consumption of both groups during and just after CPB, the difference of cerebral A-V O2 contents of Group B was greater than Group A just after CPB. These data suggest that pulsatile flow may minimize the cerebral microcirculatory shunt during CPB, resulting from the reduction of cerebral vascular resistance. 相似文献
10.