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101.
Granulocyte elastase released from activatedleukocytes plays an important role in leukocyteinfiltration. Since activated leukocytes have been shownto be involved in the pathogenesis of gastric mucosal lesion formation induced by nonsteroidalantiinflammatory drugs, inhibition of granulocyteelastase release from activated leukocytes may be usefulin the prevention of these lesions. Rebamipide, a novel antiulcer agent, inhibited granulocyte elastaserelease from activated neutrophils in vitro. Rebamipideand ONO-5046, a granulocyte elastase inhibitor, markedlyinhibited gastric mucosal lesion formation in rats. Gastric myeloperoxidase activity wassignificantly increased 3 hr after indomethacinadministration. This increase was significantlyinhibited by rebamipide and ONO-5046. Cimetidine did notinhibit granulocyte elastase release from activatedneutrophils. Although cimetidine markedly prevented theindomethacin-induced gastric mucosal lesion formation,it did not reduce the gastric myeloperoxidase activity. Therefore, unlike cimetidine, rebamipide mayprevent indomethacin-induced gastric mucosal lesionformation by inhibiting neutrophil activation.  相似文献   
102.
Typical angioid streaks were found on routine ophthalmologic examination in a 42-year-old female with yellowish, coalescing papules on her neck without any symptoms. Biopsy of the cutaneous lesion showed degeneration and fragmentation of the elastic fibers and many basophilic-stained calcifications in mid-dermis, which are consistent with pseudoxanthoma elasticum. Twenty-four-hour Holter electrocardiography (ECG) showed sinus arrest for 2.5 seconds, and an electrophysiological study revealed sinus nodal dysfunction (sick sinus syndrome), whereas all of the coronary arteries were intact, despite a treadmill stress ECG test showing significant ST depressions. The association of pseudoxanthoma elasticum and sick sinus syndrome is very rare. One possible explanation for this association here is that the degeneration of elastic fiber in endomysium of the sino-atrial node may have affected heart conduction systems, resulting in sick sinus syndrome.Part of this work was presented at the 76th Japanese Circulation Society Kyushu Meeting, Japan, June 18, 1994  相似文献   
103.
104.
Journal of Interventional Cardiac Electrophysiology - Clinical implication of local impedance (LI) for radiofrequency (RF) ablation has not been fully established. This study aimed to investigate...  相似文献   
105.
106.
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   
107.
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   
108.
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   
109.
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   
110.
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   
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