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101.
The aim of our study was to evaluate whether corrected QT dispersion (QTc dispersion), an electrocardiographic marker, is a good predictor of the development of acute heart failure after high-dose chemotherapy followed by autologous or allogeneic hematopoietic stem cell transplantation. We enrolled 50 consecutive patients, from age 15 to 63 years, with hematopoietic diseases scheduled to undergo autologous or allogeneic hematopoietic stem cell transplantation, and compared QTc dispersion with other markers before transplantation conditioning. In univariate logistic analysis, QTc dispersion was a significant factor for acute heart failure after hematopoietic stem cell transplantation (odds ratio, 3.7 per 10 msec; confidence interval, 1.6-8.5; P = 0.002). There were no significant differences as age, sex, systolic or diastolic echocardiographic function markers, cumulative anthracycline dose, or QTc before transplantation between patients with and without acute heart failure. After multiple adjustments for left ventricular ejection fraction, cumulative anthracycline dose, cyclophosphamide conditioning dose, QTc dispersion was a significant and independent factor for acute heart failure after hematopoietic stem cell transplantation (odds ratio, 48.0 per 10 msec; confidence interval, 1.4-1666.3; P = 0.03). This study demonstrated that QTc dispersion could be used as a powerful noninvasive predictor of the development of acute heart failure after hematopoietic stem cell transplantation.  相似文献   
102.
The treatment of patients with aggressive subclasses of myelodysplastic syndrome (MDS) remains a challenge. In an effort to improve the survival of patients with refractory anemia with excess blasts (RAEB), RAEB in transformation (RAEB-t), or acute myelogenous leukemia transformed from MDS (MDS-AML), we conducted a small trial in which 28 such patients were treated with low-dose cytosine arabinoside (LDAraC) followed by administration of macrophage colony-stimulating factor (M-CSF). The overall rate of response to the treatment was 61%, including 39% with a complete response, which is higher than rates obtained in previous studies in which LDAraC alone was administered to patients with MDS. Median survival was 23.5 months in cases of RAEB, 16.7 months in cases of RAEB-t, and 19.7 months in cases of MDS-AML. The overall survival of the study group appeared to be prolonged in comparison with a historical control group of patients treated with LDAraC alone. It is suggested that M-CSF added to the administration of LDAraC plays an active role in the therapy. No therapy-related death occurred. Some unique actions of M-CSF were suggested in this trial. It is concluded that therapy with LDAraC + M-CSF is a useful treatment option for patients with aggressive subclasses of MDS and MDS-AML to provide better response and survival.  相似文献   
103.
Nucleolar organizer regions (NORs) are loops of DNA which transcribes to ribosomal RNA. The NOR-related protein becomes visible in nucleus by a silver-staining technique under a light microscope, and it has been named argyrophilic protein of NOR (Ag-NOR). In various malignancies, the correlation between the proliferation potential of tumor cells or histological grade and the number of Ag-NORs has been reported. In this study, we investigated the Ag-NOR of acute leukemic cells and its relation to the in vivo proportion of bone marrow leukemic cells in DNA synthetic phase. The number of Ag-NORs in bone marrow leukemic cells was more than that in peripheral blood (means values 2.78 and 2.48, respectively, p less than 0.01). This result shows that the number of Ag-NORs reflects the vigorous proliferative potential of bone marrow leukemic cells. However, no significant correlation was obtained between the number of Ag-NORs and the bromodeoxyuridine-labeling indices (r = 0.2064). These results suggest that Ag-NOR might be one of the markers for cellular proliferation in leukemia, while DNA synthesis of leukemic cells do not seem to be directly related to Ag-NOR. In order to clarify the role of Ag-NOR in leukemia, further studies are needed.  相似文献   
104.
BACKGROUND: Wireless capsule endoscopy (CE) and double-balloon enteroscopy (DBE) are new methods enabling diagnostic endoscopy of the entire small intestine. However, which of the two is superior is unclear. We therefore prospectively compared the clinical efficacy of CE and DBE. METHODS: We prospectively examined 32 patients with obscure gastrointestinal bleeding. CE preceded DBE by 1-7 days, and all patients underwent DBE twice, by antegrade and retrograde approaches, to evaluate the entire small intestine. Physicians evaluating the results of CE and DBE were blind to the results of the other method. We evaluated diagnosis, diagnostic yield of the two methods, and clinical outcomes. RESULTS: CE revealed abnormal findings in 29 (90.6%) of 32 patients. CE definitively or probably detected the sources of bleeding in 23 (71.9%) of the 32 patients, including angioectasias (eight), erosions (seven), ulcers (five), tumor (one), and hemorrhagic polyps (two). DBE definitely or probably detected the sources of bleeding in 21 (65.6%) of the 32 patients, including angioectasias (seven), erosions (four), ulcers (five), tumor (one), hemorrhagic polyps (two) and diverticula (two). CE yielded more abnormal findings than DBE (CE 90.6%, DBE 65.6%) (P = 0.032), although there were no significant differences in diagnostic yield between the methods. We were able to perform additional treatment or biopsy with DBE in 13 patients, including coagulation therapy (ten), endoscopic mucosal resection (one), biopsy (seven), and extraction of retained CE (two). CONCLUSIONS: Our results demonstrate the superiority of CE in detecting abnormal lesions, and the superiority of DBE in endoscopic management.  相似文献   
105.
A study was conducted on the effects of perhexiline on myocardial phosphorylase activity, myocardial catecholamine content and heart rate. Phosphorylase a activity and heart rate were investigated as an indicator of sympathetic nerve tone in order to clarify the characteristic of perhexiline with regard to the effects on myocardial metabolism in hyperthyroid rats and catecholamine deficient rats. Myocardial catecholamine and phosphorylase a activity were measured by von Euler's method and Cori's method respectively. Conclusion of this study are summarized as follows: 1) Perhexiline reduces the heart rate, and its effect is not always dependent upon the changes in myocardial norepinephrine content. 2) Perhexiline reduces myocardial phosphorylase a activity. It cannot be always said that the reduction is dependent upon the changes in myocardial norepinephrine. 3) Though slightly different from propranolol and dichloroisoproterenol, perhexiline possesses cardiac effects resembling beta-blockers.  相似文献   
106.
Ventricular septal rupture is a serious complication of acute myocardial infarction. We experienced a case of septal rupture immediately after primary angioplasty with thrombolysis, whose angiographic findings were similar to those of coronary perforation. The progression of septal rupture was delineated by the serial angiograms. Catheter Cardiovasc Interv 2004;62:466–470. © 2004 Wiley‐Liss, Inc.  相似文献   
107.
It has long been held that the parathyroid glands and parathyroid hormone evolved with the emergence of the tetrapods, reflecting a need for new controls on calcium homeostasis in terrestrial, rather than aquatic, environments. Developmentally, the parathyroid gland is derived from the pharyngeal pouch endoderm, and studies in mice have shown that its formation is under the control of a key regulatory gene, Gcm-2. We have used a phylogenetic analysis of Gcm-2 to probe the evolutionary origins of the parathyroid gland. We show that in chicks, as in mice, Gcm-2 is expressed in the pharyngeal pouches and the forming parathyroid gland. We find that Gcm-2 is present not only in tetrapods but also in teleosts and chondrichthyans, and that in these species, Gcm-2 is expressed within the pharyngeal pouches and internal gill buds that derive from them in zebrafish (Danio rerio), a teleost, and dogfish (Scyliorhinus canicula), a chondrichthyan. We further demonstrate that Gcm-2 is required for the formation of the internal gill buds in zebrafish. We also have identified parathyroid hormone 1/2-encoding genes in fish and show that these genes are expressed by the gills. We further show that the gills express the calcium-sensing receptor, which is used in tetrapods to monitor serum calcium levels. These results indicate that the tetrapod parathyroid gland and the gills of fish are evolutionarily related structures, and that the parathyroid likely came into being as a result of the transformation of the gills during tetrapod evolution.  相似文献   
108.
109.
Discovery of innate lymphoid cells (ILCs), which are non–T and non–B lymphocytes that have no antigen-specific receptors, changed the classical concept of the mechanism of allergy, which had been explained mainly as antigen - specific acquired immunity based on IgE and Th2 cells. The discovery led to dramatic improvement in our understanding of the mechanism of non–IgE-mediated allergic inflammation. Numerous studies conducted in the past decade have elucidated the characteristics of each ILC subset in various organs and tissues and their ontogeny. We now know that each ILC subset exhibits heterogeneity. Moreover, the functions and activating/suppressing factors of each ILC subset were found to differ among both organs and types of tissue. Therefore, in this review, we summarize our current knowledge of ILCs by focusing on the organ/tissue - specific features of each subset to understand their roles in various organs. We also discuss ILCs’ involvement in human inflammatory diseases in various organs and potential therapeutic/preventive strategies that target ILCs.  相似文献   
110.
Journal of Artificial Organs - Perioperative hyperglycemia, hypoglycemia, and high glycemic variability are independent risk factors for mortality in critically ill patients. After cardiac surgery,...  相似文献   
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