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To explore more fully the relationship between neuronal death and neurofibrillary degeneration, unaffected neurons, intracellular neurofibrillary tangles (i-NFT) and extracellular NFT (e-NFT) in 22 patients with late-onset sporadic Alzheimer's disease (AD) were morphometrically evaluated in eight subdivisions of the hippocampal cortex, using the Gallyas hematoxylin-eosin stain. The subdivisions examined included CA4, CA3, CA2, CA1 (CA: cornu ammonis), prosubiculum (PRO), subiculum and presubiculum (PRE), parasubiculum (PARA) and the entorhinal cortex (ENT). The unaffected neuron density was significantly lower and both i-NFT and e-NFT densities were significantly higher in subdivisions other than CA4 and CA3 in AD patients compared with those in the aged controls. Unaffected neuron density was significantly, inversely correlated with e-NFT density and with total NFT density in all subdivisions except for PRE in AD patients. Especially in CA2, CA1, PRO and ENT, there were strong correlations between the neuron density and these NFT densities. Both unaffected neuron and e-NFT densities in CA1 and ENT were significantly correlated with the disease duration. The i/e-NFT ratio, an index of the degree and/or rate of progress of neuronal death via neurofibrillary degeneration, showed the lowest value in ENT in AD patients. The findings suggest that neuronal death via neurofibrillary degeneration starts earliest and/or most rapidly progresses in ENT. Furthermore, the i/e-NFT ratios in both ENT and CA1 were significantly correlated with the disease duration, suggesting that the neuronal death pattern in the two subdivisions parallels disease progression.  相似文献   
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BACKGROUND/AIMS: This study was designed to clarify the clinicopathologic characteristics and survival in early gastric remnant cancer and compare with early primary cancer in the upper third of the stomach. METHODOLOGY: Twenty-five patients with early gastric remnant cancer, who underwent resection at Kanagawa Cancer Center and First Department of Surgery, Yokohama City University between 1974 and 1996 were evaluated in this study. Various clinicopathologic characteristics, such as age, sex, symptoms, size of tumor, depth of invasion, lymph node metastasis, cell differentiation, and survival were investigated and early gastric remnant cancer was compared with early primary cancer in the upper third of the stomach. RESULTS: According to the macroscopic type, protruded type such as I or II type accounted for a great majority in early gastric remnant cancer, while II c depressed type was common in early primary cancer in the upper third of the stomach, comprising 64.2% of all cases. Pathological examination disclosed that well-differentiated carcinoma and mucosal carcinoma were more frequently observed in early gastric remnant cancer than in early primary cancer in the upper-third of the stomach. The 5-year survival rate was 83.5% for early primary cancer in the upper-third of the stomach. In contrast, no patients experienced recurrence after operation for early gastric remnant cancer. CONCLUSIONS: From the view point of clinicopathological evaluation, gastric remnant cancer is a special from of gastric cancer. A follow-up program is important in order to detect early gastric remnant cancer. A low incidence of lymph node metastasis suggests that endoscopic mucosal resection of the tumor or limited operation could be performed under strict indication.  相似文献   
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To study the contribution of age to the outcome of rheumatoid arthritis (RA), 133 elderly-onset RA (ERA) patients (onset above 60-year-old) were selected out of 2164 out-patients with RA who (i) first visited the hospital within 2 years after onset of the disease, (ii) received no remission inducing drugs previously and (iii) who were treated in this hospital regularly without interruption for more than 2 years. The joint score of ERA patients between initial visit and final visit to the hospital was compared with that of matched 133 younger-onset RA (YRA) patients (onset below 60-year-old). Results indicated that, in ERA, the patients with no active joints requiring no remission inducing drugs were increased on final visit (P<0.001). Joint score at disease onset or on initial visit to the hospital was similar in the two groups, whereas joint score on final visit was significantly decreased in ERA (P=0.0001). In ERA, progression of the small joint disease and joint erosion was not accelerated, and the small joint disease was in fact decelerated as compared with YRA (P<0.0001) during initial visit and final visit. Discriminant function analysis of patients with or without no active joints on final visit reveals that joint erosion, in small joints on initial visit is a predictor of joint prognosis in ERA. The two groups were similar with regards to sex, disease duration, onset type and rheumatoid factor/antinuclear antibody positivity. Thus, older age is an independent marker of better joint prognosis of RA  相似文献   
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Adrenaline increases the rate of cross-bridge cycling in rat cardiac muscle   总被引:1,自引:0,他引:1  
To characterize the myocardial cross-bridge dynamics in catecholamine-induced positive inotropic state, we studied the effects of adrenaline (6 X 10(-6) M) on the transient central segment length (SL) response to step decrease in tension in rat right ventricular papillary muscle in barium contracture. The time course of this response is thought to reflect the kinetics of actin-myosin interaction. The muscle was released stepwise from the steady contracture tension (Tc) to new steady tension levels (Tr) of varying magnitudes at 22 degrees C. When the tension decrease was less than 0.7 Tc, the SL transient responses comprised, in most cases, four phases. The first phase was a rapid and minute shortening during tension reduction; the second was a slow further shortening; the third, a slow lengthening; and the fourth, an extremely slow shortening toward a new steady length under the new tension. Adrenaline showed almost no effect on Tc and the amplitude of SL transients, but markedly reduced the duration of the second (D2) and third (D3) phases of SL transient regardless of the amplitude of tension reduction. The reduction of duration was 14 +/- 3% in D2 and 26 +/- 5% in D3 at Tr/Tc of 0.84 +/- 0.03 on the average (mean +/- S.D.) in nine preparations. The velocity measured from the quasi-steady SL shortening in the second phase increased with the addition of adrenaline, regardless of the amplitude of tension reduction. The increase in the shortening velocity was 16 +/- 6% (mean +/- S.D., n = 9) at Tr/Tc of 0.18 +/- 0.04. These results suggest that adrenaline increases the rate of cross-bridge cycling in cardiac muscle independent of activation level.  相似文献   
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