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101.
The anticarcinogenic potential of vitamin D might be mediated by not only calcium metabolism but also other mechanisms initiated by vitamin D receptor (VDR). The authors measured plasma 25-hydroxyvitamin D in healthy volunteer examinees who underwent total colonoscopy in Tokyo, Japan, 2004-2005, and evaluated its influence on colorectal adenoma, both alone and in interaction with VDR polymorphisms, which correspond to the FokI and TaqI restriction sites. The main analysis of plasma 25-hydroxyvitamin D included 737 cases and 703 controls. Compared with the lowest quintile of plasma 25-hydroxyvitamin D, only the highest was related to a significantly decreased odds ratio of colorectal adenoma (odds ratio = 0.64, 95% confidence interval: 0.45, 0.92). In contrast, all but the lowest quintile of dietary calcium intake presented similarly reduced odds ratios (odds ratio for the highest = 0.67, 95% confidence interval: 0.47, 0.95). Of note, the association between plasma 25-hydroxyvitamin D levels and colorectal adenoma was modified by the TaqI polymorphism of the VDR gene (P(interaction) = 0.03) but not by dietary calcium intake (P(interaction) = 0.93). These observations highlight the importance of vitamin D in colorectal tumorigenesis. Vitamin D might protect against colorectal neoplasia, mainly through mechanisms other than the indirect mechanism via calcium metabolism.  相似文献   
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We investigated the association between the Cd concentration in rice and renal dysfunction in individuals living in the Cd-polluted Jinzu River basin, using a logistic regression analysis. In the cases of logistic regression analysis for people (1) who had either resided in the present hamlet since birth or who had moved there from a non-polluted area and for those (2) who had resided in the present hamlet since birth, except for glucosuria in males, all partial correlation coefficients between the Cd concentration in rice and occurrence of abnormal urinary findings were statistically significant in both sexes. The allowable level of Cd concentration in rice was calculated by substituting the abnormality rates of urinary findings of the controls in the 40-49, 50-59 and 60-69 year age groups into the logistic regression formula for people (3). The value for subjects aged 50 years was 0.13 and 0.17 ppm for males and females, respectively, with regard to proteinuria and 0.15 and 0.10 ppm for males and females, respectively, with regard to proteinuria+glucosuria.  相似文献   
104.
We previously showed that rosmarinic acid from the leaves of Perilla frutescens Britton var. acuta Kudo (Perillae Herba) has antidepressive-like activity. The aim of the present study was to examine (i) whether caffeic acid, a major metabolite of rosmarinic acid, also has antidepressive-like activity, and (ii) whether these substances inhibit either the uptake of monoamines to synaptosomes or mitochondrial monoamine oxidase activity. Rosmarinic acid (2 mg/kg, i.p.) and caffeic acid (4 mg/kg, i.p.) each significantly reduced the duration of immobility in the forced swimming test in mice. In contrast, neither substance, at doses that produced a significant reduction in the immobile response in the forced swimming test, affected spontaneous motor activity. These results indicate that, like rosmarinic acid, caffeic acid also possesses antidepressive-like activity. In neuropharmacological studies, neither rosmarinic acid (10 x (-9)-10 x (-3) M) nor caffeic acid (10 x (-9)-10 x (-3) M) affected either the uptake of monoamines to synaptosomes or mitochondrial monoamine oxidase activity in the mouse brain. These results suggest that both caffeic acid and rosmarinic acid may produce antidepressive-like activity via some mechanism(s) other than the inhibition of monoamine transporters and monoamine oxidase.  相似文献   
105.
Little is known about the effect of normal-range blood pressure (BP) on cognitive function. In previous studies investigating the relationship between BP and cognitive function in elderly subjects, underlying cerebrovascular damage has complicated the interpretation of results. To reveal the relationship between BP levels that were within an absolutely normal range and cognitive function, we examined cognitive function in normotensive, healthy middle-aged women. BP levels were measured on three separate occasions at 1-month intervals, and the subjects exhibiting normotension (< 140/90 mmHg) throughout the evaluation period were recruited as normotensive subjects. Cognitive function was assessed using subtests of the Wechsler Adult Intelligence Scale-Revised. The study demonstrated that, among the subtests examined, the scores on the Digit Symbol Test, an index of psychomotor performance, had a significant correlation with normotensive-range systolic blood pressure (SBP) (r=-0.51, p<0.05); this relation was negative-that is, higher but still normal-range SBP levels were associated with impaired Digit Symbol Test scores. In addition, the relationship adjusted by age and educational level was also significant (partial correlation = -0.56, p<0.05). In contrast, diastolic BP was not related to the Digit Symbol Test (r = -0.33, p = 0.13). Furthermore, the Digit Symbol Test was not influenced by blood glucose or serum cholesterol levels. These findings suggested that, even within the normotensive range, lower levels of SBP might be protective against impairment of psychomotor speed in middle-aged women.  相似文献   
106.
The double contrast pharyngogram by use of computed radiography (DCP-CR) has been found to be useful in detection of asymptomatic swallowing dysfunction. Following the DCP-CR examination, we investigated the incidence of aspiration pneumonia in 143 patients with chronic cerebrovascular disease (CVD) for 3 years and the effects of ACE inhibitors on the prevention of pneumonia. Aspiration pneumonia occurred in 29 out of 143 patients, and more frequently in the elderly chronic CVD patients with multiple brain lesions. Aspiration pneumonia was confirmed in 26 out of 85 patients (30.6%) with abnormal barium adhesion to the pharyngeal wall on the double contrast pharyngogram image by DCP-CR; whereas pneumonia occurred in 3 out of 58 patients (5.2%) with normal findings of DCP-CR pharyngogram. Among chronic CVD patients with abnormal findings of DCP-CR pharyngogram, the incidence of aspiration pneumonia was significantly lower in the patients treated with ACE inhibitors than in those treated with other antihypertensive agents or without antihypertensive agents (chi 2 value = 7.163, p < 0.05). Accordingly, ACE inhibitors may prevent the aspiration pneumonia and reduce the incidence of aspiration pneumonia in the chronic CVD patients with abnormal DCP-CR pharyngogram images.  相似文献   
107.
The efficiency of the vascular-tissue system for oxygen (O2) transport in the skeletal muscle was estimated by using Krogh's cylinder model for the capillary-tissue arrangement. The tissue mass supplied by a single capillary was calculated as the region of positive O2 tension. For given values of total muscle flow and tissue O2 consumption rate, total tissue mass was determined as the function of the capillary number (n). The energy cost to maintain the vascular system with n terminals (capillaries) was assessed by the minimum volume model by Kamiya and Togawa (1972). The efficiency of the entire system was evaluated by calculating the ratio of (total tissue mass) or (total O2 consumption)/(the energy cost). The results of the calculation using physiological data of muscle blood flow and O2 consumption rate in man during exercise revealed the optimum capillary number to be around 1.5 x 10(10) and the Krogh cylinder radius to be 26 microns, which agrees well with the morphological data of these values in human skeletal muscles. It was concluded that the vascular-tissue system in the skeletal muscle is constructed so as to attain the highest efficiency in O2 transport to tissue during exercise.  相似文献   
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Clebopride malate is therapeutically used for the treatment of peptic ulcer. This drug has potent antidopaminergic activity that causes acute dystonic reaction, parkinsonism and tardive dyskinesia as adverse effects. Here, we have reported an 86-year-old man who developed abnormal involuntary movement of respiratory muscles and lower limb muscles after this drug had been given for four months. This involuntary movement appeared spontaneously at resting state and disappeared during sleep. Surface EMG demonstrated a synchronous grouping discharge in m. orbicularis oris, m. sternocleidomastoideus and m. interstales which synchronized with diaphragmatic movement on cinefluorography. Involuntary movement of the lower limbs was synchronous bilaterally and had little relationship with diaphragmatic movement. This involuntary movement was irregular not only in rhythm but also in duration. According to this irregular nature, we diagnosed this involuntary movement as respiratory dyskinesia with limb dyskinesia that belongs to tardive dyskinesia. After cessation of clebopride malate limb dyskinesia disappeared rapidly and respiratory dyskinesia markedly decreased. We emphasize that respiratory dyskinesia should be differentiated from psychogenic hyperventilation as easily misdiagnosed on initial examination.  相似文献   
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