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21.
The antihypertensive effect of bopindolol, a long-acting beta-adrenoceptor blocking agent, was investigated in stroke-prone spontaneously hypertensive rats (SHRSP). One group received tap water during the period of 8 to 32 weeks of age. The average dose of bopindolol administered was calculated from water intake to be approximately 1.4 mg/kg/day. The lowering effect in blood pressure of bopindolol was apparent at the age of 14 weeks, and this continued up to the end of the experiment. Bopindolol significantly reduced the heart rate. Plasma levels of urea nitrogen (BUN), triglyceride, and phospholipid of SHRSP treated with bopindolol were lower than those of the control SHRSP. One of the 8 control SHRSP died, and no rats treated with bopindolol died during the experiment. The histopathological study revealed that three of the control SHRSP had cerebral apoplexy, whereas there was no evidence of cerebral apoplexy in the treated SHRSP. Chronic treatment of bopindolol clearly alleviated myocardial fibrosis and hypertrophic changes in the left ventricular wall of the heart. Decreases in the incidence of proliferative arteritis and malignant nephrosclerosis in the kidney and necrotizing arteritis of the mesenteric arteries were observed in SHRSP treated with bopindolol. The data presented indicate that bopindolol is a powerful antihypertensive agent.  相似文献   
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The authors examined the relationship between cerebral white matter changes and mental function, blood pressure in 39 neurologically normal aged (21 males, 18 females, mean age 75.0 years) who had no latent lesions on MRI images. The severity of cerebral white matter changes was estimated by T1 value images on MRI and was measured in the bilateral frontal lobe on an axial slice at the level of the basal ganglia and in the bilateral anterior, middle, and posterior portions on axial slices at the level of the body of the lateral ventricle. Mental function was measured by the Hasegawa's dementia rating scale (HDS) and Kohs' block design test (Kohs' test). The severity of cerebral frontal white matter changes increased significantly with age (p less than 0.05). However there was no significant correlation between the severity of cerebral white matter changes and HDS, Kohs' test. The severity of frontal white matter changes correlated with the mean arterial blood pressure (p less than 0.02). These results suggest that the severity of cerebral white matter changes is not related with mental function in the normal elderly, and that the severity of frontal white matter lesions is related with mean arterial blood pressure.  相似文献   
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The effects of direct revascularization of the bronchial artery after bronchoplasty were estimated by laser Doppler velocimetry and india ink injection in dogs. Bronchoplastic surgery at the right main bronchus was performed in all dogs, and the bronchial artery was reconstructed using the internal thoracic artery in the reconstruction group. The mucosal blood flow was measured at the distal side of the anastomosis. India ink was injected into the aorta in the nonreconstruction group and into the internal thoracic artery in the reconstruction group. The peripheral blood flow had diminished immediately after surgeries to 59% of the baseline value and took 14 days to recover to the baseline value in the nonreconstruction group. However, in the reconstruction group, the blood flow recovered at once to 78% of the baseline value and had returned to that value in 5 days. Statistically significant differences were noted between the groups from just after operation to day 7. India ink data confirmed these findings. In the nonreconstruction group, no ink was observed in the peripheral bronchial vessels on day 3; it was noted in part of the vessels on day 7 and in most on day 14. On the other hand, a relatively large number of vessels were stained just after operation in the reconstruction group. Thus reconstruction of the bronchial artery by means of the anastomosis with the internal thoracic artery can be said to be a useful and effective method for preventing airway ischemia.  相似文献   
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The effects of nilvadipine on the peripheral circulation in the lower extremities using a duplex system of two-dimensional colour and pulse Doppler ultrasonography were studied in 32 patients with type 2 diabetes mellitus and mild essential hypertension. The patients (19 men and 13 women) were randomly divided into treatment and control groups. The anatomical cross-sectional area and blood flow index of the dorsal pedis artery were determined by colour and pulse Doppler ultrasonography before and 60 min after administration of 4 mg nilvadipine or placebo. Pulse rate and blood pressure were measured simultaneously. There were no significant changes in pulse rate or blood pressure after administration of either drug. Both cross-sectional areas (from 4.3 +/- 0.4 to 5.2 +/- 0.5 mm2, p < 0.05) and blood flow index (from 40.3 +/- 4.3 to 58.8 +/- 9.0, p < 0.05) were significantly increased in the treatment group, whereas there were no significant changes in either measurement in the control group. The findings showed that a single administration of nilvadipine increases blood flow in the dorsal pedis arteries of diabetic patients.  相似文献   
25.
The concentration of ceftazidime was determined in the aqueous humor and the vitreous body of normal, vitrectomized and aphakic/vitrectomized eyes and in the serum of albino rabbits 1 h after intravenous injection of 100 mg/kg ceftazidime. The intravitreal ceftazidime concentration was low (0.1-0.2 microgram/ml) in normal eyes 1 h after intravenous injection, and high (8.7 +/- 8.5 micrograms/ml) in vitrectomized and aphakic/vitrectomized eyes when injected immediately after surgery. The ceftazidime concentration was also determined in the aqueous humor and the vitreous body of normal eyes and in the serum of albino rabbits 3, 6, 12, 24 and 48 h after intravitreal injection of 200 micrograms. The intravitreal ceftazidime concentration after intravitreal injection decreased exponentially for 12 h (half-life about 7.4 h). It decreased more slowly thereafter and remained at 13.0 micrograms/ml (mean) even 48 h after injection. This concentration exceeded the minimum inhibitory concentrations against common gram-positive and gram-negative organisms causing endophthalmitis.  相似文献   
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The aim of this study was to investigate influence of delayed gastric emptying on postprandial reflux in esophageal pH. Sixty-nine consecutive patients underwent 24 hour (h) esophageal pH monitoring and gastric emptying. In 24 h esophageal pH monitoring, % postprandial reflux pH<4 for 2 h after each meal (% PRT) was extracted from the 24 h pH profile. After solid test meal (1 mCi, Tc99m) was given, gastric emptying was measured with a gamma detector placed transnasally 5 cm below lower esophageal sphincter. % PRT was similar among the 34 normal, 26 delayed and 9 rapid gastric emptying rate patients. Thirty-five with a positive pH study and 34 with a negative had a similar prevalence of gastric emptying disorder. In the positive pH study group, patients with normal gastric emptying had significantly higher % PRT than those with delayed gastric emptying (22.0 vs 12.1%, P<0.05). In the same population, patients with a normal %PRT had a significantly higher prevalence of delayed gastric emptying compared with those with a positive % PRT (6/8 vs 9/27, P<0.05). In patient with abnormal acid exposure but normal % PRT on 24 h esophageal pH monitoring, gastric emptying may be delayed.  相似文献   
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