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171.
Background: Many studies have shown an increase in the prevalence of arrhythmias with advancing age. However, little is known about arrhythmias in centenarians. Method and Results: Thirty-two Japanese centenarians aged 100–106 years (14 males, 18 females) were studied. All of them had 12-lead EGGs, and 22 also had 24-hour ambulatory monitoring. As controls, 89 healthy Japanese elderly from the same geographic area underwent 12-lead ECG. Their mean age was 75 ± 6 years with a range of 63–93 years, and there were 28 males and 61 females. Twenty-three of them also had Holter ECGs. On the 12-lead ECG, the heart rate was slightly, but significantly, higher in the centenarians (76.8 ± 12.7 beats/min) than that in the elderly subjects (74.9 ± 5.9 beats/min, P < 0.005). PQ and QTC were significantly longer in the centenarians (174 ± 29 and 439 ± 33 msec, respectively) compared with the elderly subjects (158 ± 23 and 417 ± 31 msec, P < 0.005 and P < 0.001, respectively). Supraventricular premature beats (SVPBs) were observed in 31% of the centenarians and in 4% of the elderly subjects (P < 0.001). First- and second-degree AV block was recorded in 25% of the centenarians and 1% of the elderly subjects (P < 0.001). Right bundle branch block was found in 19% of the centenarians and 7% of the elderly subjects (P < 0.05). There were no differences in the frequency of ventricular premature beats (VPBs) or QRS voltage. On the Holter ECG, there were no significant differences in average heart rate, maximum heart rate, minimum heart rate, or the longest RR interval. A subgroup of centenarians had frequent SVPBs. However, none of them had > 1,000 VPBs/day as opposed to four elderly subjects (P < 0.01). Atrial fibrillation was not observed in any records of the centenarians despite the presence of frequent SVPBs. Conclusion: These data suggest that conduction disturbances of the AV nodal—His-Purkinje system and frequent SVPBs are common in centenarians, whereas very frequent VPBs and atrial fibrillation seem less common.  相似文献   
172.
Fibroblast growth factor-1 (FGF-1) and FGF-2 are broad spectrum mitogens. The expression of FGF-1, FGF-2, and their receptor, FGF receptor-1 (FGFR-1), was examined in malignant salivary gland tumours and normal salivary glands, using immunohistochemical methods. In seven cases of adenoid cystic carcinoma (ACC), both duct-like cells and modified myoepithelial cells were apparently immunopositive for FGF-1, FGF-2, and FGFR-1. In five cases of mucoepidermoid carcinoma (MC), all three types of tumour cells including epidermoid cells, mucous cells, and intermediate cells expressed immunoreactive FGF-1, FGF-2, and FGFR-1. In these malignant salivary gland tumours, increased expression of FGFR-1 correlated with the intensity of both FGF-1 and FGF-2 immunoreactivity. In contrast to malignant salivary gland tumours, eight cases of normal salivary gland showed negative immunostaining for FGF-1, FGF-2, and FGFR-1 while four cases were weakly immunoreactive for FGF and its receptor. These results demonstrate that malignant salivary gland tumours overexpress FGF-1, FGF-2, and FGFR-1 compared with normal salivary glands and suggest that these growth factors may play an important role in facilitating neoplastic progression in human salivary glands.  相似文献   
173.
Purpose: The purpose of this study was to evaluate the amount of fluoride released from compomer restorative materials after immersion in various media. Materials and Methods: In this test, four materials were used: three compomers (Dyract, Dentsply, Konstanz, Germany; Compoglass, Vivadent, Schaan, Principality of Liechtenstein; and Xeno, Sankins, Tochigi, Japan) and one resin‐modified glass ionomer cement (Fuji II LC, GC, Tokyo, Japan). There were four test solutions: one alcoholic (whiskey), two low‐pH drinks (Coca‐Cola, orange juice), and one deionized water. Over a period of 60 days, the tested specimens were immersed in the test solution for 3 hours every day, then kept in deionized water. The fluoride released was detected by using a fluoride ion selective electrode connected to a microprocessor ion analyzer. The fluoride ion concentration (ppm) of the test solutions and deionized water was recorded after 1, 2, 3, 4, 7, 30, and 60 days. Electron probe microanalysis was used for surface analysis of the fluoride released. Results: When immersed in low‐pH soft drinks, compomer showed a significantly higher fluoride release than when immersed in deionized water (p <.0001). For specimens immersed in Coca‐Cola, the fluoride release levels (pg/cm2, mean ± SD) at 1, 7, and 60 days for Dyract (91.6 ± 1.8, 39.3 ± 3.1, 10.5 ± 0.9), Compoglass (129.5 ± 0.9, 66.5 ± 2.7, 19.0 ± 0.3), Fuji II LC (147.0 ± 4.2, 50.8 ± 3.1, 27.6 ± 3.0), and Xeno (73.6 ± 3.2, 27.3 ± 2.1, 6.6 ± 0.6) demonstrated the trend of significantly lower releases with time in water solution. Over a 60‐day period, materials immersed in 100% orange juice released the highest amount of fluoride, which could be attributable to the erosive effect of the medium. Materials immersed in deionized water released the least amount of fluoride. Among the tested compomers, Compoglass released the most fluoride. CLINICAL SIGNIFICANCE The results of this study indicate that, at low pH, compomer restorative materials tend to release more fluoride.  相似文献   
174.
175.
Global cerebral ischemia and reperfusion (I/R) often result in high mortality. Free radicals play an important role in global cerebral I/R. Xanthine oxidoreductase (XOR) inhibitors, such as allopurinol, have been reported to protect tissues from damage caused by reactive oxygen species (ROS) by inhibiting its production through XOR inhibition. The recently introduced XOR inhibitor febuxostat, which is a more potent inhibitor than allopurinol, is expected to decrease free radical production more effectively. Here, we analyzed the effects of allopurinol and febuxostat in decreasing global severe cerebral I/R damage in mice. Mice were divided into three groups: a placebo group, an allopurinol group, and a febuxostat group. Pathological examinations, which were performed in each group in the CA1 and CA2 regions of the hippocampus 4 days after I/R surgery, revealed that there was a decrease in the number of neuronal cells in the 14-min occlusion model in both regions and that drugs that were administered to prevent this damage were not effective. The enzymatic activity was extremely low in the mouse brain, and XOR could not be detected in the nonischemic and ischemic mice brains with western blot analyses. Thus, one of the reasons for the decreased effectiveness of XOR inhibitors in controlling severe whole-brain ischemia in a mouse model was the low levels of expression of XOR in the mouse brain.  相似文献   
176.
Retrograde Multiple Accessory Pathway Precipitating AF. Introduction : The determinants of susceptibility to atrial fibrillation (AF) and the existence of accessory pathway conduction have remained unidentified in the Wolff-Parkinson-White (WPW) syndrome. We tested the hypothesis that excitation inputs into the atrium over a retrograde multiple or multifiber accessory pathway during AV reentrant tachycardia (AVRT) could precipitate initiation of AF.
Methods and Results : Two hundred fifty consecutive patients with WPW syndrome underwent electrophysiologic study and radiofrequency catheter ablation. The patients were classified into two groups according to the study results: 29 with retrograde multiple or multifiber accessory pathway (MP) and 221 with retrograde single accessory pathway (SP). Compared with the SP patients, the MP patients showed a significantly higher incidence of clinical AF (MP vs SP: 19/29 vs 51/221, P < 0.01), induced AF (12/29 vs 32/221, P < 0.01), and initiated AF during ventricular pacing and AVRT (10/12 vs 17/32, P < 0.05). There were no differences between the two groups in incidence of clinical and induced AVRT (24/29 vs 200/221 and 25/29 vs 206/221, respectively), mean cycle length of induced AVRT, or electrophysiologic parameters of the accessory pathway. AF inducibility during AVRT or ventricular pacing was eliminated by partial ablation in 7 of 10 patients with MP. After total ablation, the incidence of induced AF was similar between the two groups (MP vs SP: 1/29 vs 11/221).
Conclusion : The existence of a retrograde multiple or multifiber accessory pathway in patients with WPW syndrome is associated with a higher incidence of clinical and induced AF. Successful ablation of the retrograde multiple or multifiber accessory pathway can eliminate the induction of both AVRT and AF.  相似文献   
177.
POLYARTHRITIS ASSOCIATED WITH HEPATITIS C VIRUS INFECTION   总被引:2,自引:0,他引:2  
Two cases of polyarthritis associated with hepatitis C infectionare reported. In Patient 1, stiffness and polyarthritis occurredduring the acute stage of hepatitis. The arthritic symptomslasted for 4 months. A transient polyarthritis recurred 4 yrlater. The persistent presence of anti-hepatitis C viral antibodieswas noted. Hepatitis C viral RNA (HCV RNA) was identified inthe serum using the polymerase chain reaction proving that thepatient was a carrier. In Patient 2, polyarthritis occurredassociated with chronic hepatitis C liver disease. Synovialiopsy showed infiltration of mononuclear cells HCV RNA was demonstratedin both serum and SF. These cases suggest an aetiologic associationbetween arthritis and hepatitis C antigenaemia. KEY WORDS: Polyarthritis, Hepatitis C virus carrier, Chronic antigenaemia  相似文献   
178.
Background: The pathogenesis of impaired water excretion in liver cirrhosis has not been fully elucidated. Methods: We induced an intravenous water overload of 20 ml/kg body weight in 10 cirrhotics without ascites (CLC), 11 cirrhotics with ascites (DLC), and 10 normal subjects (N) and investigated the relationship of plasma levels of substance P (SP), norepinephrine (NE), and antidiuretic hormone (ADH) to impaired water excretion. Results: Free water clearance (CH2O) was lower in DLC (mean, 2.7 ml/min) than in N (8.3 ml/min; P &lt; 0.001) and CLC (6.9 ml/min; P &lt; 0.001). In DLC the creatinine clearance (CCr), maximal urine flow rate/CCr, (CH2O-CNa)/CCr, and mean arterial pressure (MAP) were significantly lower than in N and CLC. There was a progressive increase in basal SP, from lowest in N to CLC, to highest in DLC. Basal NE increased in CLC and DLC. Basal ADH did not differ among N, CLC, and DLC. In cirrhotics CH2O was correlated positively with serum albumin and cholinesterase and negatively with the retention rate of indocyanine green at 15 min. Basal SP was negatively correlated with CH2O (r = -0.71; P &lt; 0.001) and MAP (r = -0.56; P &lt; 0.005). Basal NE was correlated positively with basal SP (r = 0.67, P &lt; 0.01). Conclusions: Decreased CH2O is closely related to the severity of the liver disturbance. Decreased CCr and reduced delivery of filtrate to the ascending limb of the loop of Henle secondary to an increased sodium reabsorption in the proximal tubule may play an important role in the impairment of water excretion. The increase in SP, which has a potent vasodilatory action, and the associated enhanced activity of the sympathetic nervous system may be responsible for the mild or moderate impairment of water excretion in the absence of nonosmotic hypersecretion of ADH in cirrhotics with ascites.  相似文献   
179.
A case of bromocriptine‐induced musical hallucinations in a 67‐year‐old patient with probable Lewy body dementia is reported. The patient was given bromocriptine for the treatment of parkinsonism. At a bromocriptine dosage of 7.5 mg, the patient complained, ‘I hear karaoke songs in the inner part of my head.’ The musical hallucinations gradually decreased after administration of the drug was discontinued. Bromocriptine is known to cause hallucinations, but not musical hallucinations. The dopaminergic effect of bromocriptine and the patient's cognitive impairment might have acted together to generate the musical hallucinations.  相似文献   
180.
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