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991.
BACKGROUND: Previous cross-sectional studies have suggested that cardiac autonomic regulation, measured as heart rate (HR) variability, is altered upon ageing, and that altered HR variability may predict mortality. However, there are no longitudinal follow-up reports of the changes of HR dynamics in elderly subjects. AIM & METHOD: This study was designed to examine the longitudinal changes in the spectral, fractal, and complexity measures of HR variability in a random sample of 41 elderly subjects (mean age 69+/-4 years), who underwent repeated 24-hour Holter recordings at the baseline and after 16 years' follow-up. Several cardiovascular risk factors were determined at the baseline. RESULTS: A time-domain index, standard deviation of N-N intervals (SDNN) (142+/-34 msec versus 133+/-50 msec, not significant (NS)), and the high frequency spectral component of HR variability (219+/-222 msec(2)versus 268+/-287 msec(2), NS) did not change during the follow-up. The low frequency power (LF) of HR variability decreased from 678+/-654 msec(2) to 436+/-651 msec(2) (P<0.01). Among the fractal HR variability indexes, the power-law slope (ss) (-1.31+/-0.20 versus -1.47+/-0.21, P<0.001) and the short-term fractal exponent a1 (1.16+/-0.19 versus 1.06+/-0.18, P<0.01) decreased significantly. Approximate entropy remained unchanged. CONCLUSIONS: The magnitude of total HR variability and the respiratory vagal modulation of HR do not change over time in the elderly. However, the spectral and fractal characteristics of HR behavior still undergo alterations upon ageing.  相似文献   
992.
993.

Background

Endoscopic removal of benign tumours of papilla is increasing. Our aim was to evaluate the outcome of endoscopic resection of papillary tumours.

Methods

In the years 2000–2012, 61 papillectomies were performed in Helsinki University Central Hospital. The cases were analysed retrospectively.

Results

There were 35 patients with benign tumour of papilla without familial adenomatous polyposis (FAP), 16 patients with FAP and 10 patients with ampullary cancer. Jaundice and bile duct dilation were risk factors for malignancy (p < 0.001). In benign tumours, the recurrence rate was 25.5 %. In 5/51 benign tumour cases (9.8 %), a pancreaticoduodenectomy was performed. The remaining cases were treated endoscopically. Neither tumour size, resection in one piece or piecemeal technique, nor coagulation of resection margins had an effect on the development of residual tumour. The total complication rate was 24.6 %. Pancreatitis developed in six patients (9.8 %, 3 mild and 3 moderate). In benign tumour cases, pancreatic stent decreased pancreatitis rate (p = 0.045). In cases where only a pancreatic sphincterotomy was performed, the risk of pancreatitis was high 4/7 (57 %). Bleeding was the most common complication (18 %). Only one patient was operated due to complication, a post-papillectomy bleeding. In six out of seven non-operated cancer patients, the disease progressed.

Conclusion

Endoscopic papillectomy is an effective procedure for treating benign papillary tumours. Jaundice and bile duct dilation are more common in malignant tumours. Pancreatic stent decreases the risk of post-papillectomy pancreatitis. Pancreatic sphincterotomy without stenting carries a high risk of pancreatitis. For papillary cancer, surgery is recommended.  相似文献   
994.
Human papilloma virus (HPV) infection in the larynx often requires frequent surgical procedures in order to keep voice quality reasonable. The purpose of this study was to evaluate the speaking voice quality of patients with longstanding recurrent laryngeal papillomatosis (RLP). The patients were seven males with adult-onset RLP whose disease had lasted over 5 years, and who were free of papilloma at the time of examination. Each patient had an age- and gender-matched control with similar smoking habits. Voice samples were recorded and acoustic analysis as well as perceptual listening test were performed. In our series a perceptual test discriminates between normal and pathological voice quality more precisely than acoustical voice analysis. It appears that the voice of the papilloma patient, even after frequent phonosurgical operations, is not deviant from the normal when analyzed acoustically, but perceptual assessment shows that overall quality is less than optimal, and roughness and breathiness are increased.  相似文献   
995.
Summary Eighteen pancreatic neuroendocrine (NE) tumours were analysed for nuclear DNA content by image cytometry (ICM) and flow cytometry (FCM). The DNA indices (DIs) obtained by ICM were somewhat higher than those obtained by FCM, but a major disagreement was present only in 1 case. Thirteen patients had been followed up at least for 6 years after the diagnosis or until death. At 6 years of follow-up all 4 patients with a tumour with a DI1.8 by ICM had died from their NE tumour or had metastatic disease, whereas all 9 patients with a smaller DI had no evidence of the disease (P=0.001). The DIs calculated from the FCM data also correlated well with the final outcome (P=0.01). A high incidence of DNA aneuploidy was found by both methods in histologically and clinically benign NE tumours; 12 (67%) were DNA aneuploid by FCM and 16 (89%) by ICM. It is concluded that pancreatic NE tumours are frequently DNA aneuploid, and both cytometric DNA methods give prognostic information in these tumours. The presence of DNA aneuploidy should not be considered as a sign of malignant behaviour in pancreatic NE tumours, whereas a large DI is associated with poor prognosis.  相似文献   
996.
Summary The effects of a 1 year training period on 13 elite weight-lifters were investigated by periodical tests of electromyographic, muscle fibre and force production characteristics. A statistically non-significant increase of 3.5% in maximal isometric strength of the leg extensors, from 4841±1104 to 5010±1012 N, occured over the year. Individual changes in the high force portions of the force-velocity curve correlated (p<0.05–0.01) with changes in weight-lifting performance. Training months 5–8 were characterized by the lowest average training intensity (77.1+2.0%), and this resulted in a significant (p<0.05) decrease in maximal neural activation (IEMG) of the muscles, while the last four month period, with only a slightly higher average training intensity (79.1±3.0%), led to a significant (p<0.01) increase in maximum IEMG. Individual increases in training intensity between these two training periods correlated with individual increases both in muscular strength (p<0.05) and in the weight lifted in the clean & jerk (p<0.05). A non-significant increase of 3.9% in total mean muscle fibre area occurred over the year. The present findings demonstrate the limited potential for strength development in elite strength athletes, and suggest that the magnitudes and time courses of neural and hypertrophic adaptations in the neuromuscular system during their training may differ from those reported for previously untrained subjects. The findings additionally indicate the importance of training intensity for modifying training responses in elite strength athletes.  相似文献   
997.
998.

Introduction  

Catechol-O-methyltransferase (COMT) has soluble (S-COMT) and membrane bound (MB-COMT) isoforms. Our aims were to assess the behavioral phenotype of S-COMT mutant mice and to clarify the role of MB-COMT in dopamine metabolism in different brain areas.  相似文献   
999.
Summary To investigate the effects of a combination of simultaneous strength and endurance training on selected neuromuscular and aerobic performance characteristics seven male cross-country skiers underwent training for a period of 6 weeks. The experimental group trained 6–9 times per week with a programme consisting of 34% explosive type strength training and 66% endurance training during the first 3 weeks of the experiment and 42% and 58% respectively during the last 3 weeks of the experiment. The total volume of training of the control group (eight skiers) was of the same magnitude but consisted of 85% pure endurance training and 15% endurance type strength training. The experimental training regime resulted in specific changes in neuromuscular performance. This was demonstrated by improvements (P<0.01) in the maximal heights of rise of the centre of gravity in the squat and countermovement jumps. A significant decrease (P<0.05) took place also in the time of rapid isometric force production during experimental training, while no changes occurred in the maximal force of the trained muscles. Aerobic performance characteristics of the experimental group did not change during the experimental training period. No significant changes occurred in neuromuscular or aerobic performance characteristics in the control group. These findings indicated that training-induced improvements in explosive force production may not be fully inhibited by this kind of aerobic training. They also suggested that endurance athletes could undertake explosive type strength training programmes without a concomitant reduction in aerobic capacity, if the overall loading of training were within predefined limits.  相似文献   
1000.
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