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排序方式: 共有3705条查询结果,搜索用时 15 毫秒
91.
Masaru Nakayama Haruki Itoh Keiko Oikawa Akihiko Tajima Akira Koike Tadanori Aizawa Long-Tai Fu Fumihiko Miyake 《Circulation journal》2005,69(6):683-687
BACKGROUND: The magnitudes of the first (WI1) and the second wave-intensity peak (WI2) during the ejection period can be used as indices of left ventricular (LV) contractility and relaxation, respectively. However, use of WI to characterize LV dp/dt and the end-diastolic volume (V ed) relationship may be more problematic, as WI may be affected by changes in preload. METHODS AND RESULTS: The LV pressure-volume data sets, consisting of 23 recordings obtained by the conductance method from 12 heart disease patients, were studied. End-systolic elastance (E es) and volume-axis-intercept (V0) were calculated with varying preload. Time constant of LV relaxation (tau), V ed, and WI were calculated from steady-state averaged data. The E es showed a weak correlation with WI1 (r = 0.46, p < 0.05) but a better correlation with preload-adjusted WI1 [WI1/V ed; r=0.86, WI1/V(ed)2; r = 0.92, WI1/(V ed - V0)2; r = 0.89, all p < 0.01]. Similarly, tau did not correlate with WI2 but did correlate with preload-adjusted WI2 [WI2/V ed; r = -0.73, WI2/V(ed) 2; r = -0.63, WI2/(V ed - V0)2; r = -0.78, all p < 0.01]. CONCLUSIONS: These data demonstrate the importance of preload-adjustment when using the WI index for simultaneous assessment of LV contractility and relaxation. 相似文献
92.
Farr MJ Lang CC Lamanca JJ Zile MR Francis G Tavazzi L Gaasch WH St John Sutton M Itoh H Mancini D;MCC- GO Investigators 《The American journal of cardiology》2008,102(2):203-206
The response to cardiopulmonary exercise (CPX) in patients with heart failure (HF) with normal left ventricular (LV) ejection fractions (EFs) is not well characterized. To determine if CPX testing could distinguish between patients with HF with normal EFs (>50%; i.e., diastolic HF) and those with decreased EFs (> or =50%; i.e., systolic HF), CPX responses were compared between 185 patients with systolic HF (79% men, mean age 62.6 +/- 10.9 years) and 43 with diastolic HF (54% men, mean age 67.4 +/- 9.8 years) enrolled in a phase II multicenter clinical trial. All patients were evaluated with echocardiography and a standardized CPX test as part of the trial. CPX variables, including oxygen uptake at peak exercise (peak VO(2)) and the slope of the ventilation/carbon dioxide production ratio (VE/VCO(2)), were determined and analyzed by core laboratory personnel. Echocardiographic measurements included the LV EF, the E/A ratio, filling time, cavity volumes, right ventricular function, and mitral regurgitation. Patients in the diastolic HF group tended to be older (p <0.08), with more women (p <0.006) and with greater body mass indexes (p <0.02), than those in the systolic HF group. There was no significant difference in the use of beta blockers or the incidence of coronary artery disease. Patients with diastolic HF had decreased E/A ratios (0.9 +/- 0.4 vs 1.4 +/- 1.1, p <0.02, diastolic HF vs systolic HF) and increased filling times (30.4 +/- 3.2 vs 26.5 +/- 4.7 ms, p <0.01, diastolic HF vs systolic HF). No significant differences in peak VO(2) (14.4 +/- 1.9 vs 15.6 +/- 3.2 ml/kg/min, p = 0.06, diastolic HF vs systolic HF) were observed. The VE/VCO(2) ratios for the 2 groups were abnormal and comparable (32 2 +/- 7.5 vs 34.0 +/- 8.3, p = 0.3, diastolic HF vs systolic HF). In conclusion, the CPX response in patients with diastolic HF and systolic HF is markedly abnormal and indistinguishable with regard to peak VO(2) and ventilation despite marked differences in the LV EF. 相似文献
93.
Osamu Toyoshima Toshihiro Nishizawa Kazuma Sekiba Tatsuya Matsuno Ryo Kondo Hidenobu Watanabe Hidekazu Suzuki Chizu Tanikawa Kazuhiko Koike Koichi Matsuda 《Journal of Clinical Biochemistry and Nutrition》2021,68(1):73
The risk allele of a single nucleotide polymorphism (SNP) rs2294008 in the Prostate stem cell antigen (PSCA) gene is strongly associated with gastric cancer. Although the Kyoto classification score is believed to be an indicator of gastric cancer risk, it lacks supporting genetic evidence. We investigated the effect of this risk allele of PSCA SNP on the Kyoto score. Participants without a history of gastric cancer or Helicobacter pylori (H. pylori) eradication underwent esophagogastroduodenoscopy, H. pylori evaluation, and SNP genotyping. The Kyoto score is the sum of scores obtained from endoscopy-based atrophy, intestinal metaplasia, enlarged folds, nodularity, and diffuse redness. The Kyoto score is novel in the light of scoring for gastritis. A total of 323 patients were enrolled (number of individuals with genotype CC: 52; CT: 140; TT: 131, average age: 50.1 years, male: 50.8%). The patient baseline characteristics including age, sex, body mass index, smoking, drinking, family history of gastric cancer, and H. pylori status had no association with PSCA SNP. The Kyoto score was higher in T (CT or TT genotype; risk allele) carriers than in CC carriers. Atrophy, enlarged folds, and diffuse redness scores were higher in T allele carriers (risk allele) than in CC genotype individuals. In multivariate analysis, the Kyoto score was independently associated with PSCA SNP (OR: 1.30, p = 0.012). Thus, the Kyoto score was associated with a genetic predisposition. 相似文献
94.
Akira Mochizuki Takahiro Namiki Yusuke Nishimori Haruki Ogawa 《Journal of biomaterials science. Polymer edition》2013,24(12):750-765
The water structure and platelet compatibility of poly(methyl methacrylate (MMA)-block-2-hydroxyethyl methacrylate (HEMA)) were investigated. The molecular weight (Mn) of the polyHEMA segment was kept constant (average: 9600), while the Mn of the polyMMA segment was varied from 1340 to 7390. The equilibrium water content of the copolymers was found to be mainly governed by the HEMA content. The water structure in the copolymers was characterized in terms of the amounts of non-freezing and freezing water (abbreviated as Wnf and Wfz, respectively) using differential scanning calorimetry. It was found that the Wnf for the copolymers were higher than those estimated from the Wnf for the HEMA and MMA homopolymers and that the amount of excess non-freezing water depended on the polyMMA segment length. In addition, X-ray diffraction analysis revealed that some of the copolymers had cold-crystallizable water. These facts suggested that the polyMMA segments were involved in determining the water structures in the copolymers. Furthermore, the platelet compatibility of the copolymers was improved as compared to that of the HEMA homopolymer. It was therefore concluded that the platelet compatibility of the copolymer was related to the amount of excess non-freezing water. 相似文献
95.
Mulyanto Sulaiman Ngongu Depamede Made Sriasih Masaharu Takahashi Shigeo Nagashima Suljid Jirintai Tsutomu Nishizawa Hiroaki Okamoto 《Archives of virology》2013,158(1):87-96
One hundred sixteen rats (Rattus rattus) captured in Indonesia from 2011 to 2012 were investigated for the prevalence of hepatitis E virus (HEV)-specific antibodies and HEV RNA. Using an ELISA based on HEV genotype 4 with an ad hoc cutoff value of 0.500, 18.1 % of the rats tested positive for anti-HEV IgG. By nested RT-PCR, 14.7 % of the rats had rat HEV RNA, and none were positive for HEV genotype 1-4. A high HEV prevalence among rats was associated with lower sanitary conditions in areas with a high population density. Sixteen of the 17 HEV isolates obtained from infected rats showed >93.0 % nucleotide sequence identity within the 840-nucleotide ORF1-ORF2 sequence and were most closely related to a Vietnamese strain (85.9-87.9 % identity), while the remaining isolate differed from known rat HEV strains by 18.8-23.3 % and may belong to a novel lineage of rat HEV. These results suggest a wide distribution of rat HEV with divergent genomes. 相似文献
96.
97.
Satoshi Kutsuna Yusuke Asai Kei Yamamoto Michinori Shirano Keiji Konishi Tomohiro Asaoka Masaya Yamato Yukiko Katsuragi Yudai Yamamoto Toshinori Sahara Aya Tamiya Fukumi Nakamura-Uchiyama Naoya Sakamoto Atsushi Kosaka Takuya Washino Ryota Hase Haruki Mito Takashi Kurita Norio Ohmagari 《Journal of infection and chemotherapy》2021,27(4):632-638
IntroductionThe epidemiology of infectious diseases in Japan remains undefined despite the increasing tourism. GeoSentinel, an epidemiological surveillance system for reporting imported infectious diseases, has only two participating facilities in Japan. Although the number of infectious diseases is reported by the National Institute of Infectious Diseases, there is no detailed clinical information about these cases. Therefore, we established J-RIDA (Japan Registry for Infectious Diseases from Abroad) to clarify the status of imported infectious diseases in Japan and provide detailed information.MethodsJ-RIDA was started as a registry of imported infectious diseases. Case registration began in October 2017. Between October 2017 and September 2019, 15 medical institutions participated in this clinical study. The registry collected information about the patient's age, sex, nationality, chief complaint, consultation date, date of onset, whether visit was made to a travel clinic before travel, blood test results (if samples were collected), travel history, and final diagnosis.ResultsOf the 3046 cases included in this study, 46.7% to Southeast Asia, 13.0% to Africa, 13.7% to East Asia, 11.5% to South Asia, 7.5% to Europe, 3.8% to Central and South America, 4.6% to North America, 3.9% to Oceania, and 2.8% to Central and west Asia. More than 85% of chief complaints were fever and general symptoms, gastrointestinal symptoms, respiratory symptoms, or dermatologic problems. The most common diseases were travelers’ diarrhea, animal bite, upper respiratory infection, influenza, and dengue fever.ConclusionsWe summarized two-year cases registered in Japan's imported infectious disease registry. These results will significantly contribute to the epidemiology in Japan. 相似文献
98.
Reconstruction of bilateral branch pulmonary artery stenosis caused by Takayasu's aortitis. 总被引:1,自引:0,他引:1
Hiroo Shikata Shigeru Sakamoto Yoshimichi Ueda Shuji Tsuchishima Toshiaki Matsubara Hisateru Nishizawa Shinji Shono Masahiro Kanno Takashi Shimizu Junichi Matsubara 《Circulation journal》2004,68(8):791-794
A 63 year-old female presented with dyspnea on exertion. Her chest X-ray showed cardiomegaly, and right ventricular overload and tricuspid regurgitation were detected. Her pulmonary ventilation and blood flow scintigraphy findings were suspicious of pulmonary vascular disease; the diagnosis was pulmonary hypertension and bilateral branch pulmonary artery stenosis. After the inflammation settled, the stenotic bilateral branch pulmonary artery was reconstructed with a prosthetic vessel and the pulmonary pressure normalized immediately. A resected specimen revealed that the stenotic changes were from Takayasu's disease. The patient's postoperative course was uneventful, and pulmonary ventilation and blood scintigraphy returned to an almost normal range. At follow-up 5 years and 6 months after the operation, there was no evidence of pulmonary artery disease (eg, stenosis and/or ischemia) or of any change in the central vessels of the retina, the so-called Takayasu's retinopathy. 相似文献
99.
Kawayama T Kinoshita T Imaoka H Gauvreau GM O'Byrne PM Aizawa H 《Respirology (Carlton, Vic.)》2008,13(7):1000-1007
Background and objective: Cytotoxic T-lymphocyte antigen 4 (CTLA-4) signalling of regulatory T cells regulates mucosal lymphocyte tolerance and differentiation, and may therefore have a beneficial effect in allergic diseases such as asthma. The aim of this study was to evaluate the effects of fluticasone propionate (FP) on CD4+CD25+ T cell co-expression of CTLA-4 in the sputum of mild asthmatic subjects. Methods: Eleven mild, stable asthmatic subjects completed a double-blind, randomized, cross-over, placebo-controlled study to compare the effects of 14 days 200 µg twice daily FP and placebo. Before and after treatment, airway hyperresponsiveness was measured, and sputum was induced for measurements of CTLA-4+CD4+CD25+ cells, eosinophils and levels of IL-10, IL-13 and transforming growth factor (TGF)-β Results: FP treatment increased co-expression of CTLA-4 on sputum CD4+CD25+ cells from a mean (SEM) of 7.9% (1.8) to 12.7% (3.3) after 14 days treatment (P < 0.05) compared with placebo. FP treatment also significantly increased IL-10 levels, reduced per cent sputum eosinophils, and reduced airway hyperresponsiveness (P < 0.05). There was a significant negative correlation between the change in airway hyperresponsiveness and per cent sputum eosinophils (P < 0.01), but no correlation with changes in CTLA-4+CD4+CD25+ cells (P > 0.05). There was no change in the levels of sputum IL-13 or TGF-β Conclusions: The percentage of airway CTLA-4+CD4+CD25+ cells increased after FP treatment, coincident with improvements in airway inflammation and hyperresponsiveness. Whether improved asthma assessments are related to the increase in CTLA-4+CD4+CD25+ cells and thus improved regulation of T-cell tolerance and differentiation will require a larger sample size to determine. The normalization of CTLA-4+CD4+CD25+ cells in asthma may contribute to the management of this disease. 相似文献
100.
Predictors for typical asthma onset from cough variant asthma. 总被引:6,自引:0,他引:6
Masaki Fujimura Yoriko Nishizawa Masaru Nishitsuji Satoshi Nomura Miki Abo Haruhiko Ogawa 《The Journal of asthma》2005,42(2):107-111
Cough variant asthma is recognized to be a precursor of asthma or preasthmatic state because nearly 30% patients with cough variant asthma develop typical asthma within several years. However, predictors for risk of typical asthma onset from cough variant asthma are unknown. Forty-one patients with cough variant asthma (median age 50 years, 13 men and 28 women), who had undertaken spirometry, bronchial reversibility test, methacholine provocation test, measurements of peripheral blood eosinophil count, serum total IgE, and specific IgE to common allergens, and induced sputum eosinophil count at presentation, were followed up with special emphasis on typical asthma onset during 1 year or more (median 4 years, range 1-12.4). Long-term inhaled corticosteroids (ICS) were taken in 27 patients. Univariate and multivariate logistic analyses were performed to determine the predictors for typical asthma onset. Asthma onset was recognized in 7 patients. Bronchial hyperresponsiveness, peripheral blood eosinophil count, and no use of ICS were significant predictors for the typical asthma onset by univariate analysis. However, only bronchial hyperresponsiveness was the significant predictor when multivariate analysis was used (adjusted OR 0.028, 95% CI 0.001-0.783, p = 0.0355). Bronchial hyperresponsiveness may be the most important predictor for risk of typical asthma onset from cough variant asthma. 相似文献