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101.
The effects of acebutolol, a cardioselective beta-adrenoceptor blocking agent, on the systolic blood pressure and heart rate were investigated in conscious Kyoto Wistar normotensive rats (WKY), spontaneously hypertensive rats (SHR) and DOCA-NaCl hypertensive rats (DOCA rats) and the results compared with those of propranolol and practolol. In WKY and DOCA rats, the intraperitoneal administration of acebutolol, propranolol and practolol (0.5 approximately 20 mg/kg) produced a hypotensive action, however, these effects were observed only with restricted doses and there was no evidence of a dose-dependency. The heart rate was decreased by acebutolol and propranolol, but was increased by practolol which possesses an intrinsic sympathomimetic activity. In SHR, propranolol produced a dual action, a slight rise followed by a slight fall, the change not being significant, while practolol induced a slight hypertension. On the other hand, acebutolol in high doses induced a dose-dependent hypotensive action. The heart rate was markedly and dose-dependently decreased by these three agents. Thus, while propranolol and practolol produced hypotensive effects in WKY and DOCA rats, acebutolol produced hypotensive effects in WKY, SHR and DOCA rats. These results suggest that acebutolol is a beta-adrenoceptor blocking agent which possesses hypotensive activity in hypertensive rats.  相似文献   
102.
Inorganic arsenite has caused severe inflammatory chronic poisoning in humans through the consumption of contaminated well water. In this study, we examined the effects of arsenite at nanomolar concentrations on the in vitro differentiation of human macrophages from peripheral blood monocytes. While arsenite was found to induce cell death in a culture system containing macrophage colony stimulating factor (M-CSF), macrophages induced by granulocyte-macrophage CSF (GM-CSF) survived the treatment, but were morphologically, phenotypically, and functionally altered. In particular, arsenite-induced cells expressed higher levels of a major histocompatibility complex (MHC) class II antigen, HLA-DR, and CD14. They were more effective at inducing allogeneic or autologous T cell responses and responded more strongly to bacterial lipopolysaccharide (LPS) by inflammatory cytokine release as compared to cells induced by GM-CSF alone. On the other hand, arsenite-induced cells expressed lower levels of CD11b and CD54 and phagocytosed latex beads or zymosan particles less efficiently. We also demonstrated that the optimum amount of cellular reactive oxygen species (ROS) induced by nM arsenite might play an important role in this abnormal monocyte differentiation. This work may have implications in chronic arsenic poisoning because the total peripheral blood arsenic concentrations of these patients are at nM levels.  相似文献   
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CD163 is a marker of activated macrophages, and increased levels of soluble CD163 have been detected in sera obtained from patients with hepatitis. The aim of this study was to detect the expression of CD163 in the liver from patients with viral hepatitis. Frozen sections of liver specimens were obtained from 5 patients with acute viral hepatitis (AH) and from 23 patients with chronic viral hepatitis (CH). The expression of CD163 in the liver was determined immunohistochemically using monoclonal antibody to human CD163. Double immunostaining was done to assess those cell types that express CD163 in the liver. The frequencies of CD163-positive cells were significantly higher both in the portal areas and in the hepatic lobules in the liver of patients with AH compared to those with CH (p < 0.05). Double immunostaining revealed that most of the CD163-positive cells were macrophages and Kupffer cells, because they expressed CD68. The expression of CD163 was very low in endothelial cells and liver stellate cells. This study shows that macrophages are activated in hepatitis liver.  相似文献   
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Binocular visual function after surgery for detached retina was examined in 100 patients with a visual acuity of less than 0.3 in the reattached retina and with a visual acuity of more than 1.0 in the non-detached retina:1) There was no significant sex difference in binocular visual function.2) There was no significant difference in binocular visual function according to postoperative interval.3) Maintenance of postoperative binocular visual function was best in patients under 19 years of age, and grew worse with age.4) In patients with a visual acuity of more than 0.1 in the reattached retina, simultaneous perception was good in 100%, and fusion in more than 80%. However, stereopsis was worse in most cases.5) In patients with a visual acuity of less than 0.1 in the reattached retina, all aspects of binocular visual function were worse, except in those under 19 years of age.6) There was no significant difference in binocular visual function between patients with and without temporary amputation of extrinsic ocular muscles at operation.7) There was no significant difference in binocular visual function between patients with and without macular detachment before operation.8) In the patients who had had an encircling operation, binocular visual function was worse than in those operated on with other procedures, because the former had the severest retinal detachment.  相似文献   
109.
T staging of gastric cancer: role of multi-detector row CT   总被引:16,自引:0,他引:16  
PURPOSE: To evaluate retrospectively the accuracy of multi-detector row computed tomography (CT) in the assessment of serosal invasion in patients with gastric cancer. MATERIALS AND METHODS: The Ethics Committee does not require approval or informed consent for retrospective studies. Forty-one consecutive patients (24 men, 17 women; mean age, 68 years) with gastric cancer were included in this study. All patients were given 600 mL of tap water to drink and were positioned prone or supine on the scanning table. The detector row configuration included four detector rows, a section thickness of 1.25 mm, a pitch of 6, and a reconstruction interval of 0.63 mm. Transverse and multiplanar reconstruction images were simultaneously evaluated by two independent observers to assess the depth of tumor invasion in the gastric wall (ie, T stage). T staging at multi-detector row CT was compared with T staging at histologic evaluation (reference standard), which was performed by means of surgical or histologic examination of the resected specimen. We also calculated the sensitivity, specificity, and accuracy of multi-detector row CT for each observer in the assessment of serosal invasion. RESULTS: Analysis of interobserver agreement showed substantial or almost perfect agreement (nonweighted kappa value of 0.78 and weighted kappa value of 0.85). Correct assessment of gastric wall invasion was 80% and 85% for observers 1 and 2, respectively. The sensitivity, specificity, and accuracy of multi-detector row CT in the assessment of serosal invasion were 90%, 95%, and 93%, respectively, for observer 1 and 80%, 97%, and 93%, respectively, for observer 2. Overstaging occurred in six patients, and understaging occurred in five patients. All understaged tumors were scirrhous subtype gastric cancer. CONCLUSION: Multi-detector row CT scanning of patients with gastric cancer gave 93% accuracy in the assessment of serosal invasion in patients with gastric cancer.  相似文献   
110.
Patients with end-stage renal disease have markedly increased risk for death from cardiovascular disease. Renal failure is associated with multiple metabolic and endocrinologic abnormalities, and these alterations are involved in advanced atherosclerosis and high cardiovascular risk. Increased insulin resistance index by homeostasis model assessment (HOMA-IR), a simple index of insulin resistance, was an independent predictor of cardiovascular mortality in nondiabetic patients on maintenance hemodialysis. Renal failure impairs lipoprotein metabolism leading to the atherogenic lipoprotein profile characterized by increased triglyceride-rich remnant lipoproteins such as intermediate-density lipoprotein, an independent factor of increased aortic stiffness. Non-high-density lipoprotein cholesterol, the sum of cholesterol of intermediate-density lipoprotein and other apoB-containing lipoproteins, is an independent factor associated with increased arterial thickness and a predictor of cardiovascular death in hemodialysis patients. The risk for cardiovascular death in hemodialysis patients is associated closely with hypertension and malnutrition, but not with obesity. The constellation of insulin resistance, dyslipidemia, hypertension, and malnutrition in renal failure suggests the presence of another type of metabolic syndrome promoting cardiovascular disease. In addition, vitamin D deficiency and abnormalities in calcium, phosphate, and parathyroid hormone levels increase the death risk from cardiovascular disease in renal failure. It is expected that treatment of these metabolic and endocrinologic alterations would improve the survival of patients with renal failure.  相似文献   
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