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991.
Toshihiko Nanke Kiyoshi Nakazawa Tsuneharu Sakurai Naoki Matsumoto Ryouji Kishi Akihiko Takagi Chuichi Sato Fumihiko Miyake Takashi Yamaki Mutsuo Kaneko 《Circulation journal》2004,68(8):751-756
BACKGROUND: A new system of synthesizing a 12-lead electrocardiogram (Syn-ECG) with practically identical waveforms to the standard 12-lead ECG (Stn-ECG) from 3-channel ECGs recorded by Holter monitoring has been developed. METHODS AND RESULTS: The study group comprised 16 healthy individuals and 13 patients with abnormal ECGs. The bipolar eV1, eV5 and eVF leads were recorded using digital Holter monitoring and nine Syn-ECGs, corresponding to each lead of the Stn-ECG, were synthesized. The 9 ECGs consisted of a theoretical Syn-ECG and 8 Syn-ECGs positioned around the theoretical Syn-ECG at 3 cm intervals on the Frank's image surface. Of the 9 ECGs, the Syn-ECG with the maximum product of the cross-correlation coefficient of the QRS wave and that of the T wave, was automatically selected as the optimal Syn-ECG. The amplitude data from the QRS wave, R wave, T wave, and ST level, and also the amplitude ratio of the R wave, T wave to the QRS wave, were significantly well correlated between the Syn-ECG and Stn-ECG. CONCLUSIONS: A practically identical ECG morphology, comparable with a Stn-ECG, was successfully created using this system. 相似文献
992.
OBJECTIVES: Right ventricular function may deteriorate after the atrial switch operation in patients with transposition of the great arteries, but the effect on left ventricular function is unknown. Chronic left ventricular function was evaluated in adult patients after the atrial switch operation for transposition of the great arteries. METHODS: Right and left ventricular functions were evaluated using data from cardiac catheterization performed in nine patients older than 17 years who had undergone the atrial switch operation for transposition of the great arteries. The mean age at operation was 19 +/- 16 months and the age at catheterization ranged from 17 to 32 years (mean age 23 +/- 5 years). Echocardiography was performed in all patients to evaluate tricuspid regurgitation. Myocardial perfusion studies using technetium-99 m-tetrofosmin were assessed in five patients. RESULTS: Mean right ventricular end-diastolic volume was slightly increased to 122 +/- 27% of the normal value and mean right ventricular ejection fraction was depressed to 44 +/- 5% of the normal value. Left ventricular ejection fraction ranged from 37% to 63% (mean 50 +/- 7%) and was under 50% in four of the nine (44%) patients. Right ventricular ejection fraction was positively correlated with left ventricular ejection fraction(r = 0.72, p < 0.05). All patients had tricuspid regurgitation, mild in four, moderate in four, and severe in one patient. Left ventricular ejection fraction was lower in patients with moderate or severe tricuspid regurgitation(54 +/- 4%) than in patients with mild tricuspid regurgitation(47 +/- 6%, p < 0.05). Mild or moderate perfusion abnormalities were observed in all patients (five of five) who underwent myocardial perfusion studies. Mean right and left ventricular ejection fractions were 43 +/- 3% and 50 +/- 3%, respectively, in patients who underwent myocardial perfusion study, which were under the normal levels. CONCLUSIONS: Left ventricular dysfunction is common in adult patients after the atrial switch operation for transposition of the great arteries. Some right ventricular abnormalities may correlate with the left ventricular dysfunction. 相似文献
993.
The role of mucosal prostaglandin levels in healing of water immersion-induced gastric ulcers in rats 总被引:1,自引:0,他引:1
M Kuroiwa S Sugiyama H Goto Y Tsukamoto S Nakazawa T Ozawa 《Scandinavian journal of gastroenterology》1990,25(1):59-65
This study was designed to clarify the recovery time course of water immersion stress ulcers. Rats were divided into two groups: the control group and the cetraxate group. In the cetraxate group, 6 h after water immersion stress, cetraxate (300 mg/kg) was administered intragastrically twice a day until the end of the experiment. Ulcer indices were observed immediately, 1, 3, 7, 14, and 21 days after water immersion stress in each group. Changes in gastric mucosal prostaglandin (PG) levels were measured by means of high-performance liquid chromatography. In the control group ulcer healing was not observed within 1 day after stress. Gastric lesions had decreased significantly after 3 days, but 21 days were required for total healing. Accelerated ulcer healing was observed in the cetraxate group. Four kinds of PGs were detected in gastric mucosa: 6-keto-PGF1 alpha, PGF2 alpha, PGE2, and PGD2. Recovery of PG levels differed from each other. Fourteen days were required for full recovery of PGD2 and 6-keto-PGF1 alpha. In contrast, 7 days were required for recovery of PGF2 alpha and PGE2. Cetraxate accelerated the recovery of gastric mucosal PGD2 and 6-keto-PGF1 alpha levels, especially the former. These results suggest that PGs, especially PGD2, are linked with the healing processes of stress ulcers. 相似文献
994.
Akihiko Takagi Kiyoshi Nakazawa Tsuneharu Sakurai Toshihiko Nanke Fumihiko Miyake 《Circulation journal》2002,66(12):1101-1104
The electrophysiological mechanism of Brugada syndrome is unclear, but transmural dispersion of repolarization in the right ventricle is believed to be the most likely mechanism. On the other hand, the presence of a conduction delay region is considered to be related to the occurrence of ventricular fibrillation; that is, a relationship between the presence of a ventricular late potential (LP) and arrhythmogenic right ventricular cardiomyopathy. In this study, the LP from signal-averaged electrocardiography during isoproterenol (ISP) administration in patients with Brugada syndrome is discussed. The subjects were 11 patients with Brugada syndrome and 6 healthy individuals. In all subjects, the total filtered QRS duration (fQRS), root mean square voltage of the 40 ms terminal portion of the QRS (RMS(40)), duration of the low amplitude electric potential component (40 microV) of the terminal portion of the QRS (LAS(40)), and time duration of the fQRS-LAS(40) difference were compared between when ISP was prescribed and when it was not. During ISP administration, a peculiar response, which resulted in an LAS(40) prolongation, was observed in the patients with Brugada syndrome. With ISP, the fQRS remained unchanged, but the RMS(40) and the fQRS-LAS(40) decreased. Consequently another 3 patients with a positive LP were diagnosed using the ordinary standard because of the administration of ISP. We believe that the low-amplitude component was unmasked by shortening of the high-amplitude component. In patients with Brugada syndrome, a conduction delay in the ventricle may be present and may be related to the occurrence of ventricular fibrillation. 相似文献
995.
Jun-o Deguchi Takatoshi Furuya Nobutaka Tanaka Hiroyuki Okamoto Tatsu Nakazawa Masakazu Nobori Tetsuro Miyata 《The International journal of angiology》2002,11(4):241-244
The purpose of this retrospective study was to assess the long-term results after exclusion of an internal iliac artery aneurysm (IIAA) to patients with high-risk conditions. From 1993 to 2000, sixteen patients (15 men and one woman, mean age 75.1 years) with 22 internal iliac artery aneurysms underwent exclusion surgery. Only two patients had solitary IIAA and the remaining fourteen had IIAA associated with abdominal aortic aneurysm (AAA) or common iliac artery aneurysm (CIAA). Of the 16 patients, there were 7 with ruptured aneurysm (43.8%) and the other 9 patients, who had underwent an elective operation, were at high risk for surgery because of existence of advanced cancer in 3, cerebrovascular disease in 2, severe chronic obstructive lung disease in 2, and liver cirrhosis or rheumatoid arthritis with long-term steroid administration in 1 each. The sacs of all IIAA (6 bilateral and 10 unilateral) were excluded without internal iliac artery reconstruction. The operative mortality was 6.3%. Non-fatal ischemic colitis occurred in one patient. Buttock claudication was not recognized. Only one excluded aneurysm expanded and underwent complete resection of the sac 45 months after the initial exclusion surgery. Delayed rupture was not observed in the follow-up periods (mean, 37.9 months). The 3-year and 5-year survival rate was 66.7% and 41.7%, respectively. The exclusion method minimizes surgical intervention and yields an acceptable outcome. This method could be the procedure of choice for high-risk patients. 相似文献
996.
Detection of verotoxin-producing Escherichia coli using polymerase chain reaction from dairy cattle]
H Tada S Itami Y Yamamoto K Kobayashi M Taguchi M Nakazawa 《Kansenshōgaku zasshi. The Journal of the Japanese Association for Infectious Diseases》1992,66(10):1383-1389
The vero cytotoxin (VT) is responsible for hemorrhagic colitis and hemolytic uremic syndrome. Polymerase chain reaction (PCR) was used to detect VT-producing coliform bacteria from dairy cattle. It was found that 39 (33.3%) of the 117 fecal samples examined were recognized with VT genes in BGLB enrichment broth by the PCR method (named BGLB-PCR). Of the VT-positive samples, 31 samples (26.5%) were found to have VT-producing Escherichia coli. Frequencies of isolation in younger cattle (under 5 months) were 31.3-32.9%. On the other hand, the PCR method using the bacterial suspension of some colonies from DHL selective isolation medium (named DHL-PCR), was used for 105 samples. The DHL-PCR was validated according to the number of colonies tested for detecting VTEC. When using E. coli strains which have been stored after isolation by the conventional culture method, the VT-producing strains found were 7 (10.3%) of the 68 isolates tested. The 101 out of the 108 VTEC strains from cattle were classified into 14 O groups. 4 O serogroups (O26, O111, O145, O157) from 60% of VTEC positive cattle, were also the most common in humans with diarrhea. All E. coli O157:H7 isolates failed to ferment after 48 hrs and to hydrolyze 4-methyl-umbelliferyl-beta-D-glucuronide (MUG). These results suggests that cattle may play an important role in human VTEC infections. The BGL B-PCR technique is usefull in ecological studies for VT-producing pathogens. 相似文献
997.
Inoue H Yasuda Y Hattori K Shimizu T Matsumoto M Yabe M Yabe H Tsuchida F Tanaka Y Hosoi G Sako M Kato S 《International journal of hematology》2003,77(4):399-407
The present study compares immune reconstitution after allogeneic cord blood transplantation (CBT) and CD34+ stem cell transplantation (CD34-SCT) with that after bone marrow transplantation (BMT). Eighty-eight children who underwent CBT (20 patients), BMT (58), and CD34-SCT (10) were enrolled, and lymphocytes and T-, B-, and natural killer-lymphocyte subsets were monitored for more than 5 years after transplantation. CBT recipients showed significant ircreases in (1) total lymphocyte counts (P < .001), (2) CD4+/CD8+ cell ratios (P < .01), (3) CD4+ and CD4+CD45RA+ cells (P < .001), (4) CD8+CD11b+ cells (P < .001), and (5) CD19+ and CD19+CD5+ cells (P < .0001) and marked decreases in the frequencies of CD8+ and CD8+CD11b- cells (P < .0001). CD34-SCT recipients showed lower lymphocyte counts in the first 6 months and an emergence of lymphocyte and CD4+CD45RA+ cells at approximately 9 months and 1 year. Both CBT and CD34-SCT recipients showed increased frequencies of CD56+ cells at 1 month (CD34-SCT versus BMT, P < .001) but decreased frequencies after 6 months (CBT versus BMT, P < .001). Lymphoproliferative responses to exogenous interleukin 2 were constantly lower in CBT and CD34-SCT recipients than in BMT recipients. These results suggest that the delay in immune reconstitution after CBT in the early phase was mainly qualitative and related to the immaturity of cells, whereas the delay in CD34-SCT was mainly quantitative in the first several months. 相似文献
998.
To investigate the mechanism of increased superoxide (O2-) generation by monocytes from patients with hypertriglyceridemia, superoxide scavenging activity (SSA) and O2- generation by monocytes were determined concomitantly employing an electron spin resonance/spin trapping method and 2-methyl-6-[p-methoxyphenyl]-3,7-dihydroimidazo [1,2-a]-pyrazin-3-one (MCLA)-dependent chemiluminescence, respectively. Peripheral monocytes were separated by the adherent methods from the following four male groups: normal control, diabetes alone (DM), diabetes with hypertriglyceridemia (DM + HTG) and hypertriglyceridemia alone (HTG). Monocytes were stimulated by 4 beta-phorbol 12 beta-myristate 13 alpha-acetate (PMA) or opsonized zymosan (OZ). O2- generation by monocytes upon stimulation was enhanced in HTG and HTG + DM but not in DM as compared to that in normal controls. The mean value of SSA in monocytes was similar among the 4 groups. When the relationship was analyzed using various parameters, a significant positive relationship was found between O2- generation and the plasma triglyceride level; a significant negative correlation was found between SSA and both the O2- generation and the plasma triglyceride level. In the in vitro system, the SSA in monocytes decreased significantly after the the stimulation by either of PMA or OZ. The results indicate that the decrease of SSA in monocytes may originate from the enhanced in vivo O2- generation and is responsible for the enhanced O2- release against the stimuli in hypertriglyceridemia. These abnormal functions of monocytes may in part accelerate the development of atherosclerosis. 相似文献
999.
Yagasaki H Inukai T Uno K Akahane K Nemoto A Takahashi K Sato H Goi K Mouri N Takano K Katoh R Sugita K Nakazawa S 《[Rinshō ketsueki] The Japanese journal of clinical hematology》2003,44(5):328-333
A 14-year-old girl was admitted because of general fatigue and cervical lymphadenopathy. She showed bilateral struma (IInd degree) and enlargement of her left cervical lymph nodes. Laboratory data revealed neutropenia (219/microliter) and thrombocytopenia (Plt 5.1 x 10(4)/microliter) with mild anemia (Hb 11.1 g/dl), and the bone marrow aspirate and biopsy specimens showed hypocellularity. In addition, auto-antibodies against thyroid peroxidase (TPO) and thyroglobulin (TG) were highly elevated. Computed tomography of the neck showed a nodule in the left thyroid lobe with marked lymphadenopathy, and fine needle aspiration biopsy demonstrated papillary thyroid carcinoma with Hashimoto's thyroiditis and metastasis to the lymph nodes. One month after left thyroid lobectomy and cervical lymphadenectomy, the patient's condition progressed to very severe aplastic anemia, and she received immunosuppressive therapy consisting of cyclosporin A and anti-thymocyte globulin. Hematologically, partial and complete responses were obtained three and six months later, respectively. Of interest, anti-TPO and TG antibody titers remarkably decreased after immunosuppressive therapy. The patient had HLA-DR 2(DRB 1*1501) and DR 8(DRB 1*0802). The former is frequently found in patients with cyclosporin A-dependent aplastic anemia, and the latter is frequently found in Asian patients with Hashimoto's thyroiditis, suggesting an underlying autoimmune background for the simultaneous outbreak of aplastic anemia and Hashimoto's thyroiditis complicated by thyroid carcinoma. 相似文献
1000.
Imashuku S Shioda Y Kobayashi R Hosoi G Fujino H Seto S Wakita H Oka A Okazaki N Fujita N Minato T Koike K Tsunematsu Y Morimoto A;Japan LCH Study Group 《Haematologica》2008,93(4):615-618
Clinical features, brain magnetic resonance imaging findings and EDSS scores of 11 patients with neurodegenerative central nervous system Langerhans cell histiocytosis were analyzed in Japan. All patients initially had multi-system-type Langerhans cell histiocytosis; 8 at 1-2 years of age and 3 at a later age. Neurodegenerative central nervous system Langerhans cell histiocytosis disease developed after a median time interval of 3.9 years from initial diagnosis. With a median follow-up of 4.5 years, 6 patients showed progression of disease with an EDSS score >3. This study demonstrates the importance of early detection of neurodegenerative central nervous system Langerhans cell histiocytosis by brain magnetic resonance imaging, particularly in the follow-up of patients who developed multi-system-type Langerhans cell histiocytosis in early infancy. 相似文献