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排序方式: 共有8002条查询结果,搜索用时 15 毫秒
991.
Matsumura N Fujimoto S Nakano H Mizuno R Negoro K Yamamoto Y Yabuta M Nonaka H Dohi K 《Echocardiography (Mount Kisco, N.Y.)》1998,15(4):401-403
A 53-year-old man with aortic regurgitation was admitted to our hospital because of fever. A diagnosis of ruptured mitral valve aneurysm was made by Doppler echocardiography. Aortic regurgitant flow along the anterior mitral leaflet may have predisposed to mitral valve endocarditis, aneurysm formation, and its rupture. 相似文献
992.
Beta-blocker therapy induces ventricular resynchronization in dilated cardiomyopathy with narrow QRS complex. 总被引:2,自引:0,他引:2
Yasuhiko Takemoto Takeshi Hozumi Kenichi Sugioka Yasuhiro Takagi Yoshiki Matsumura Minoru Yoshiyama Theodore P Abraham Junichi Yoshikawa 《Journal of the American College of Cardiology》2007,49(7):778-783
OBJECTIVES: We sought to evaluate the effects of beta-blocker therapy on regional and global myocardial mechanics in addition to ventricular synchrony in patients with heart failure and normal QRS by using tissue Doppler and strain echocardiography. BACKGROUND: It is unknown whether beta-blocker therapy can influence mechanical synchrony. METHODS: Conventional and strain echocardiography were performed in 15 healthy age-matched volunteers and in 25 patients with idiopathic dilated cardiomyopathy (IDC). Of these, 15 IDC patients on standard heart failure therapy were studied prior to and at 1 and 6 months after initiation of carvedilol therapy and compared to the controls. RESULTS: There was significant mechanical dyssynchrony in IDC compared with control patients. Patients placed on carvedilol demonstrated a significant decrease in the inferoseptal to lateral wall delay in peak strain (normalized to the R-R interval) between baseline and 1 month and between baseline and 6 months. Similarly, global time to peak segmental strain (455 +/- 51 ms vs. 423 +/- 59 ms, respectively, p = 0.02, and 455 +/- 51 ms vs. 415 +/- 50 ms, respectively, p = 0.01) and the coefficient of variation of the time to peak segmental strain decreased (17 +/- 4% vs. 15 +/- 5%, respectively, p = 0.02, and 17 +/- 4% vs. 14 +/- 5%, respectively, p = 0.03), from baseline to 1 month and between baseline and 6 months, respectively. Global strain significantly increased from baseline to 1 month (-8.2 +/- 1.8 to -10.4 +/- 3.9, respectively, p = 0.01) and between baseline and 6 months (-8.2 +/- 1.8% to -12.0 +/- 3.2%, respectively, p = 0.008). Improvements in left ventricular ejection fraction and reverse remodeling were coincident with reductions in mechanical dyssynchrony. CONCLUSIONS: The use of carvedilol improves contractile function and dyssynchrony in heart failure patients with normal QRS. 相似文献
993.
Fukuda S Hozumi T Watanabe H Muro T Yamagishi H Yoshiyama M Takeuchi K Yoshikawa J 《Echocardiography (Mount Kisco, N.Y.)》2005,22(2):111-119
BACKGROUND: Measurement of left ventricular (LV) volumes and ejection fraction (EF) is important in managing patients with coronary artery disease (CAD). Introduction of free-hand three-dimensional echocardiography (3DE) system which is equipped with small magnetic tracking system and average rotational geometry for LV volumes may provide easy and accurate quantification of LV systolic function in CAD patients. PURPOSE: To evaluate the feasibility and accuracy of LV volumes and EF measurement by free-hand 3DE with rotational geometry in patients with CAD. METHODS AND RESULTS: The study subjects consisted of consecutive 25 patients with CAD who were scheduled for quantitative gated single-photon emission computed tomography (QGS). LV end-diastolic volume (EDV), end-systolic volume (ESV), and EF were determined by conventional two-dimensional echocardiography (2DE), 3DE, and QGS. Three-dimensional echocardiography data acquisition and analysis were possible in 22 of 25 subjects (feasibility 88%). In this 3DE system, image acquisition time was 2 minutes, and 5 minutes were needed for off-line analysis of LV volumes and EF. Correlations and the limits of agreement between 3DE and QGS (r = 0.97, 0.0 +/- 9.1 ml for EDV, r = 0.99, 0.0 +/- 5.0 ml for ESV, and r = 0.97, 0.5 +/- 3.3% for EF, respectively) were superior to those between 2DE and QGS (r = 0.85, 12.6 +/- 26.8 ml for EDV, r = 0.85, 9.7 +/- 26.1 ml for ESV, and r = 0.90, -1.3 +/- 6.9% for EF, respectively). Inter- and intra-observer variabilities of 3DE were smaller than that of 2DE (5% vs 10%, 5% vs 10% for EDV, 6% vs 13%, 5% vs 9% for ESV, and 4% vs 11%, 4% vs 6% for EF, respectively). CONCLUSION: Three-dimensional echocardiography using magnetic tracking system and average rotational geometry offered a feasible and accurate method for quantification of LV volumes and EF in patients with CAD. 相似文献
994.
Cell proliferation in the dentate gyrus of rat hippocampus is inhibited by soft diet feeding 总被引:1,自引:0,他引:1
BACKGROUND: Recently it has become well accepted that neurogenesis occurs in the dentate gyrus of the hippocampus, a region important to memory and learning function in rodents and humans. Reports show that neurogenesis in the hippocampus is regulated by certain factors, such as exposure to an enriched environment, physical activity, aging and stress. The relationship between the change in the task of chewing as one oral environmental factor, and the mechanisms of hippocampal neuron generation are unclear. OBJECTIVE: We examined whether cell proliferation varies by chewing tasks with different food textures in the dentate gyrus of the rat hippocampus. METHODS: Wistar rats were divided into two groups, one was fed a solid diet, known as the hard-diet feeding group, and the soft-diet feeding group, which was fed a powder diet containing the same components as the solid one for 3, 7, 16 and 24 weeks. Thymidine analog 5-bromo-2'-deoxyuridine (BrdU) was used as a marker of cell proliferation within the dentate gyrus of the hippocampus and olfactory bulb. RESULTS: The results of this study indicated that the total number of BrdU-positive cells in the hippocampal dentate gyrus significantly decreased with aging and were significantly fewer in the soft-diet feeding group than in hard-diet feeding group in 7-, 16- and 24-week-old rats after the BrdU injection. The change of BrdU-positive cell expression between soft and hard diets in 3- and 24-week-old rats was not observed in the olfactory bulb. CONCLUSION: It has been suggested that cell proliferation in the dentate gyrus of the rat hippocampus is characteristically suppressed by soft diet feeding. 相似文献
995.
Nobukazu Ishizaka Yuko Ishizaka Ei-Ichi Toda Hideki Hashimoto Ryozo Nagai Minoru Yamakado 《Hypertension research》2005,28(1):27-34
The cluster of metabolic and hemodynamic risk factors known as metabolic syndrome is known to be a risk factor for ischemic cardiovascular diseases and stroke. By analyzing the cross-sectional data from 8,144 individuals (age 19-88 years) who underwent general health screening, we have investigated the prevalence of metabolic syndrome, as diagnosed by modified-National Cholesterol Education Program (NCEP) criteria corresponding to the following five categories: triglycerides > or = 150 mg/dl; high density lipoprotein (HDL)-cholesterol < 40 mg/dl in men or < 50 mg/dl in women; fasting plasma glucose > or = 110 mg/dl; systolic/diastolic blood pressure > or = 130/85 mmHg; and body mass index > 25 kg/m2. We found that the prevalence of metabolic syndrome was 19% in men and 7% in women. After adjustment for age, metabolic syndrome was found to be significantly more prevalent in men than in women, with an odds ratio of 3.08 (95% confidence interval [CI] 2.62-3.61, p < 0.0001). Among the five metabolic/hemodynamic risk factor components, hypertension was observed most frequently in individuals with metabolic syndrome, at 85% in men and 87% in women. In addition, multivariate logistic regression analysis adjusted for age, sex, serum total cholesterol levels, and smoking status showed that hypertension possessed the greatest odds ratio (1.43, 95% CI 1.27-1.60) for carotid plaque among the metabolic/hemodynamic risk factors. These data emphasize the importance of controlling blood pressure for reducing the risk of both metabolic syndrome and carotid arteriosclerosis in apparently healthy individuals. 相似文献
996.
Yasuhiro Nakamura Minoru Yoshiyama Takashi Omura Ken Yoshida Shokei Kim Kazuhide Takeuchi Hiroshi Iwao Junichi Yoshikawa 《Circulation journal》2002,66(2):192-196
Many studies have suggested that the renin-angiotensin system plays an important role in the left ventricular (LV) remodeling and cardiac dysfunction that occurs after myocardial infarction (MI). Although angiotensin II type IA (AT1A) receptor knockout (KO) mice are reported to display less LV remodeling after MI, diastolic dysfunction has not been fully evaluated, so the present study measured transmitral inflow pattern in both AT1A receptor KO mice with MI (KO-MI) and wild type mice with MI (WT-MI). Cardiac geometry and function were examined by Doppler echocardiography and myocardial mRNA expression was determined by Northern blot analysis at 4 weeks after MI. The LV internal diastolic dimension of WT-MI was larger than that of the KO-MI (p<0.05). Marked increases in the E wave velocity and the ratio of the peak velocity of the E wave to the A wave were observed in the WT-MI (p<0.01). The deceleration rate of the E wave in KO-MI was lower than in WT-MI (p<0.05). mRNA expressions of ANP, BNP, collagen I and collagen III in the non-infarcted LV and RV of KO-MI were significantly lower than WT-MI. In conclusion, transmitral inflow abnormalities in KO-MI were attenuated compared with WT-MI. 相似文献
997.
Tetsuro Inoue Eisaku Tanaka Minoru Sukuramoto Masayoshi Minakuchi Yuji Maeda Ko Maniwa Kunihiko Terada Kiminobu Tanizawa Seishu Hashimoto Shunsuke Goto Tomoshi Takeda Masaki Okamoto Yoichiro Kobashi Yoshiaki Yuba Satoshi Noma Yasuyuki Yoshizawa Yoshio Ohtani Yoshio Taguchi 《Nihon Kokyūki Gakkai zasshi》2006,44(8):550-555
We retrospectively evaluated 8 cases of bird related hypersensitivity pneumonitis in Tenri hospital, all of whom underwent surgical lung biopsy. They had a history of contacting with birds and had serological studies using lymphocyte stimulation test to pigeon serum or antibody in serum and bronchoalveolar lavage fluid to pigeon dropping extracts yielded positive results. Computed tomography revealed a radiographic pattern unlike typical UIP. The result of pathological diagnosis of surgical lung biopsy was 'others' or NSIP pattern. Only one case had pathological findings of granuloma. Four cases had an improved or stable course only offer segregation from bird antigens. The other four cases needed corticosteroids and immunosuppressants, and two of the four cases had a progressive course and died of respiratory failure. 相似文献
998.
Whole-body periodic acceleration enhances brachial endothelial function. 总被引:10,自引:0,他引:10
Tetsuya Matsumoto Masatoshi Fujita Yasuhiro Tarutani Tetsunobu Yamane Hiroyuki Takashima Ichiro Nakae Minoru Horie 《Circulation journal》2008,72(1):139-143
BACKGROUND: Periodic acceleration in the direction of the spinal axis through repetitive movement increases the shear stress on the vascular endothelium. In the present study it was assessed whether whole-body periodic acceleration with a new device would enhance endothelial function in sedentary adult volunteers. METHODS AND RESULTS: Twenty-six sedentary subjects (44+/-3 years) were randomly assigned to remain sedentary or perform exercise training for 4 weeks, followed by crossover. Periodic acceleration was applied with a horizontal motion platform at 2-3 Hz and approximately +/-2.2 m/s2 for 45 min. Increases in the brachial artery diameter were examined at rest, during reactive hyperemia (flow-mediated dilatation: %FMD) and after sublingual administration of 0.3 mg nitroglycerin (%NTG) using high-resolution ultrasound. All subjects completed the study with no adverse side-effects. There were no significant changes in the resting heart rate or arterial pressure, body weight, or lipid profiles during the study. Although %FMD did not change during the non-training period with periodic acceleration, it significantly increased from 7.3+/-0.4% at baseline to 8.4+/-0.4% after the training period (p<0.05), while %NTG remained unchanged. CONCLUSIONS: Whole-body periodic acceleration with a horizontal motion platform improved vascular endothelial function in sedentary adults. This device might offer an alternative to active exercise for patients whose medical condition limits physical activity. 相似文献
999.
Yoshifumi Hatakeyama Ms Masaaki Tomoi Phd Minoru Ohtsuka Phd Kyoichi Shimomura 《Digestive diseases and sciences》1997,42(12):2560-2565
The effects of subcutaneous loperamide ongastric lesions induced by necrotizing agents wereinvestigated in the rat. Loperamide produced adose-dependent increase of gastric fluid volume andinhibition of gastric lesions caused by 0.6 N HCl orabsolute ethanol. Pretreatment with naloxone almostcompletely blocked both fluid pooling effect and mucosalprotective effect of loperamide. Omeprazole reduced the acidity of the gastric fluid in ratstreated with loperamide without significantly decreasingthe fluid volume. Various volumes of acid, given orallyimmediately before 0.6 N HCl, volume-dependently prevented gastric lesions. We conclude thatsubcutaneous loperamide protects the gastric mucosaagainst necrotizing agents through luminal dilution ofirritants, which is mediated by naloxonesensitive opiate receptors. 相似文献
1000.
Minoru Kanazawa Makoto Nagata Yoshinori Terashi Michiya Yamaguchi Koshu Nagao Takao Takizawa 《Nihon Kokyūki Gakkai zasshi》2004,42(12):994-1000
A questionnaire survey of the current medical therapy in patients with mild persistent (step 2) asthma was conducted of doctors professing internal medicine in Saitama prefecture. Responses were obtained from 933 of those surveyed (response rate: 53%). Medications frequently prescribed for asthma control were theophylline (77%), inhaled corticosteroids (ICSs: 75%), and leukotriene modifiers (64%). Usage of theophylline in exacerbation reached 87% and was given priority over inhaled beta2-agonist, suggesting too much usage of theophylline among respondents. ICSs were used in 75% of respondents. Doctors specializing in respiratory or allergic medicine used ICSs more frequently than the others. They started ICSs at large doses initially (48%), followed by small doses, and they showed a trend of continuing ICSs after the asthma was under control (75%). Eighty-three percent of respondents used leukotriene modifiers, which were evaluated as easy to administer orally, having a synergistic effect with ICSs, and having fewer side effects compared with other asthma medications. 相似文献