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141.
Determining the type of cardiac dysfunction is important for implementing therapeutic strategies and for prognostic insights. We characterized systolic dysfunction (SD) and isolated diastolic dysfunction (IDD) in adults referred for echocardiographic evaluation, and compared their clinical and other characteristics. In the present work, we studied 218 patients (137 males) with cardiac dysfunction (mean age, 66.3 +/- 8.3 years). SD was defined as a left ventricular ejection fraction (LVEF) of < 45%, whereas IDD was defined as a LVEF >or= 45% in addition to the standard Doppler-echocardiography diagnostic criteria for IDD. Approximately 68% of subjects had SD (70% males). The proportions of hypertension, diabetes, and dyslipidemia were 44%, 26%, and 22%, respectively, without significant association with the type of dysfunction. Myocardial infarction (MI) was found in 31% of patients, and was significantly (P < 0.001) more prevalent among SD compared with IDD cases. Cerebral stroke (18%) and malignancy (16%) were significantly associated with IDD (29% versus 13% for SD in the case of stroke, and 26% versus 11% for SD in the case of malignancy; P = 0.008 for each). In multivariately-adjusted logistic regression analysis, the following variables were found to be significantly (P < 0.05) and independently associated with IDD: female gender (odds ratio [OR] = 2.207 [95% CI = 1.302-4.608]), stroke (OR = 2.009 [1.119-3.980]), and malignancy (OR = 2.016 [1.230-4.010]). On the other hand, previous MI (OR = 2.075 [1.769-4.808]) was independently associated with SD. In conclusion, some factors/comorbidities were more likely to associate with IDD (female gender, stroke, and malignancy) or SD (previous MI) when IDD and SD were compared with each other.  相似文献   
142.
143.
We examined the brain activation induced by a complex finger movement task using functional magnetic resonance imaging (fMRI) with echo planar imaging (EPI). Imaging planes were set up for the observation of non-primary motor areas. Among five normal males examined, four subjects naive to the task showed activations in contralateral primary and supplementary motor areas and the ipsilateral superior anterior part of the cerebellar hemisphere. Also, the bilateral premotor areas and the contralateral ventrolateral nucleus of thalamus were occasionally activated. No changes were observed in the putamen and globus pallidus. The subject accustomed to the task showed activation in the narrow areas of the contralateral primary motor and supplementary motor and premotor areas but not in the cerebellum. These results suggest that fMRI has nearly the same degree of detectability to that of positron emission tomography (PET) in regard to motor functions.  相似文献   
144.
Electromagnetic interference (EMI) with electronic medical equipment by radio waves from mobile telephone handsets has been reported and is currently receiving wide attention. The possibility of EMI with electronic medical equipment by radio waves coming into the hospital has also been pointed out. But so far, there are no reports measuring the frequency distribution of electric field intensity induced by incoming radio waves. Therefore, we measured electric field intensity induced by radio waves coming into our 11-floor hospital, which was under construction. The maximum intensity observed was about 200 V/m at 2.79 GHz, from airport surveillance radar waves. The maximum intensity induced by radio waves from cellular phone base stations was 1.78 V/m. These data show that various frequencies of radio waves are common in this urban area, and that they induce strong electric field intensity. This strong electric field intensity might cause EMI with electronic medical equipment. Measurement of the electromagnetic environment should be done by each hospital in urban areas to prevent EMI with electronic medical equipment.  相似文献   
145.
The transport of solutes between blood and brain is regulated by a specific barrier. Capillary endothelial cells of brain are known to mediate barrier function and facilitate transport. Here we report that specific cells surrounding arterioles, known as Mato's fluorescent granular perithelial (FGP) cells or perivascular microglial cells, contribute to the barrier function. Immunohistochemical and in situ hybridization studies indicate that, in normal brain cortex, type I and type II macrophage scavenger receptors are expressed only in FGP/perivascular microglial cells, and surface markers of macrophage lineage are also detected on them. These cells mediate the uptake of macromolecules, including modified low density lipoprotein, horseradish peroxidase, and ferritin injected either into the blood or into the cerebral ventricles. Accumulation of scavenged materials with aging or after the administration of a high-fat diet results in the formation of honeycomb-like foam cells and the narrowing of the lumen of arterioles in the brain cortex. These results indicate involvement of FGP/perivascular microglial cells in the barrier and scavenger functions in the central nervous system.  相似文献   
146.
Cardiomyocytes can be generated from marrow stromal cells in vitro   总被引:370,自引:0,他引:370       下载免费PDF全文
We have isolated a cardiomyogenic cell line (CMG) from murine bone marrow stromal cells. Stromal cells were immortalized, treated with 5-azacytidine, and spontaneously beating cells were repeatedly screened. The cells showed a fibroblast-like morphology, but the morphology changed after 5-azacytidine treatment in approximately 30% of the cells; they connected with adjoining cells after one week, formed myotube-like structures, began spontaneously beating after two weeks, and beat synchronously after three weeks. They expressed atrial natriuretic peptide and brain natriuretic peptide and were stained with anti-myosin, anti-desmin, and anti-actinin antibodies. Electron microscopy revealed a cardiomyocyte-like ultrastructure, including typical sarcomeres, a centrally positioned nucleus, and atrial granules. These cells had several types of action potentials, such as sinus node-like and ventricular cell-like action potentials. All cells had a long action potential duration or plateau, a relatively shallow resting membrane potential, and a pacemaker-like late diastolic slow depolarization. Analysis of the isoform of contractile protein genes, such as myosin heavy chain, myosin light chain, and alpha-actin, indicated that their muscle phenotype was similar to that of fetal ventricular cardiomyocytes. These cells expressed Nkx2.5/Csx, GATA4, TEF-1, and MEF-2C mRNA before 5-azacytidine treatment and expressed MEF-2A and MEF-2D after treatment. This new cell line provides a powerful model for the study of cardiomyocyte differentiation.  相似文献   
147.
The purpose of the present study was to analyze the determinants of nurse staffing in urban public hospitals in Japan. The study sample included 51 public hospitals in 23 urban cities in 1996. Structural equation modeling was performed using the following: nurse-to-inpatient ratio; medical service and hospitalization fees; approved nurse staffing level; outpatient-to-inpatient ratio; subsidy-to-hospital-revenue ratio; and regional variation index of inpatient service expenditures. The nurse-to-inpatient ratio was associated with medical service fees reflecting patients' acuity levels and the subsidy-to-hospital-revenue ratio, but was not associated with the hospital income from hospitalization fees (the largest share of which consists of nursing fees). Public hospitals in areas with limited inpatient care resources had a higher level of approved nurse staffing and a higher subsidy-to-hospital-revenue ratio. A significant determinant of public hospitals' nurse staffing was local government-funded subsidization rather than the balance between nursing service fees and costs.  相似文献   
148.
149.
To clarify the invasive process of Vibrio parahaemolyticus, an invasion assay was performed using cells expressing dominant negative small GTPases of the Rho family. This assay showed that the dominant negative host phenotype facilitates bacterial invasion, suggesting that the mechanism of V. parahaemolyticus invasion differs from that reported for other invasive bacteria.  相似文献   
150.
This study investigated inhibitory factors in anger expressive behaviors among Japanese junior high school students. It also examined the relations between anger experiences and personality traits: verbal expression and narcissism. The result indicated that the factors of "friend relationships" and "cost-reward consciousness" were selected as those which inhibited anger expressive behaviors. Results of a covariance structure analysis were as follows. First, narcissistic personality elicited feelings of anger and depression and cognitions of inflating and calming, which all facilitated aggressive behavior, social sharing, and object-displacement as anger expressive behaviors. Second, verbal expression elicited cognitions of objectifying and self-reproaching, and the former inhibited anger expressive behaviors, though the latter facilitated them. Finally, "cost-reward consciousness" inhibited anger expressive behaviors for boys, while "normative consciousness" inhibited them for girls.  相似文献   
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