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1.
Introduction   QT interval prolongation may cause the potentially lethal tachyarrhythmia torsades de pointes ( 1 ). The cause of the QT interval prolongation may be a congenital mutation in genes encoding cardiac potassium and sodium channels ( 2 ) or be acquired following drug administration ( 3 ) or metabolic disorders ( 4 ). Among a few other drugs volatile anaesthetics prolong the QT interval. During the last few years sevoflurane has become the most used volatile anaesthetic for the induction of anaesthesia in infants.
Methods   This investigation, on infants aged from 1 to 6 months, was approved by the institutional ethic committee. Thirty-six otherwise healthy infants due to elective surgery were included in our study The patients were randomly assigned to one of two treatment groups. Group S ( n  = 24) was anaesthetised with sevoflurane, Group H was anaesthetised with halothane. ECG recordings were taken before the anaesthesia onset, 15 min after the first contact with the volatile anaesthetic and 60 min after the ending of the volatile gas exposition. QTc interval was calculated using the Bazett's formula ( 5 ).
Results   QTc interval was significantly ( P < 0.0002) (Table 1) lengthened 15 min after anaesthesia induction with sevoflurane as well as 60 min ( P < 0.01) after the ending of the gas exposition without any difference in age and gender. The QTc interval in patients anaesthetised with halothane did not show any significant change.  

  Table 1  相似文献   

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Mechanism of bronchodilator effect in chronic airflow limitation.   总被引:1,自引:0,他引:1       下载免费PDF全文
OBJECTIVE: To examine the mechanisms through which two bronchodilators (theophylline and salbutamol) influence dyspnea during daily activities. METHODS: Twenty-four patients with chronic airflow limitation participated in a multiple crossover, randomized, placebo-controlled trial. The effect of theophylline and salbutamol, alone or combined, on pulmonary function and dyspnea during daily activities was examined. Correlations of changes in forced expiratory volume in 1 second (FEV1) and maximum expiratory pressures (MIPs) (independent variables) and changes in dyspnea score during daily activities (dependent variable) were also examined. RESULTS: The two drugs proved to be beneficial the effects in general were additive rather than synergistic. The drugs improved the FEV1; theophylline significantly improved the MIPs. The correlation between the changes in FEV1 and those in dyspnea score, after adjustment for the changes in MIPs, was 0.55 (p less than 0.001). The correlation between the changes in MIPs and those in dyspnea score, after adjustment for the changes in FEV1, was 0.39 (p less than 0.001). CONCLUSIONS: Changes in airway calibre and in respiratory muscle strength play an independent and important role in dyspnea during daily activities in patients with chronic airflow limitation. Changes in airway calibre may be of greater importance.  相似文献   
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Lymphocytes from 10 paired colostrum and peripheral blood specimens were examined to determine if the colostral T cell population differs from the peripheral blood T cell population in subset distribution. The percentages of lymphocytes staining with OKT3, OKT4, and OKT8 murine monoclonal antibody were determined. Lymphocytes from colostrum were 74.7 +/- 2.5% OKT3+, 50.6 +/- 2.3% OKT4+, 24.0 +/- 1.7% OKT8+, whereas peripheral blood lymphocytes were 78.7 +/- 1.9% OKT3+, 48.4 +/- 1.4% OKT4+, and 29.8 +/- 1.6% OKT8+. The percentage of colostrum lymphocytes positive for OKT3 was significantly although not strikingly lower than the OKT3 percentage for blood lymphocytes (p less than 0.05). This difference was due to the lower percentage of OKT8 positive lymphocytes in colostrum compared with blood (p less than 0.01). Although the T cell subset distribution of colostrum generally appears to be similar to that in the peripheral blood, there were small differences in OKT3 and OKT8 percentages that were statistically significant suggesting the possibility of some selectivity of the colostral T cell population.  相似文献   
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P Hildebrand  U J Roblick  R Keller  M Kleemann  L Mirow  H-P Bruch 《Der Chirurg》2007,78(6):494, 496-494, 500
Minimizing the access trauma of surgical interventions is becoming an essential task in modern surgery in order to make the treatment more comfortable for the patient. Minimally invasive surgery has had a major impact on the improvement of surgical results over the last decade. This is why such surgery is often named as the third patient friendly revolution in surgery after the introduction of asepsis and anesthesia. Operations that caused a huge strain on the patients in the past and led to immense costs for society because of the patient's lost working time and extensive rehabilitation, have lost their fear thanks to this technique. The physical strain is lower, the cosmetic effect is considerable and the costs for society might be reduced due to the significantly shorter duration of convalescence.Despite its known advantages, which have been reported in numerous studies, minimally invasive surgery has recently gained increased interest because of the installation of new accounting systems as well as strict budgeting and restricted resources.Realistic cost-benefit analysis and objectified quality controls are needed in order to guarantee innovative and patient friendly basic approaches in medicine in the future.  相似文献   
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OBJECTIVE: As more patients are diagnosed with prostate cancer at an early stage, it is becoming increasingly important to refine the technique of surgical excision. For this purpose we have generated objective data comparing three different surgical approaches used by three experienced surgeons. METHODS: We prospectively compared three contemporary personal series of 50 consecutive radical prostatectomy (RP) patients. The health-related quality of life was evaluated preoperatively and in months 1, 3, 6, 12 and 24. RESULTS: Considering in turn the patients undergoing retropubic, perineal and laparoscopic RP, the median procedure time was 2 h and 27 min, 1 h and 50 min and 4 h, with a transfusion rate of 2, 0 and 8%, respectively. In the perineal group there were more wound infections. Median catheter drainage was 7, 10 and 7 days and zero, 13 and one patients needed reinsertion of a catheter. Early continence varied considerably, with 57.4, 11.4 and 6.3% of patients pad-free after 1 month, but there were no differences in social continence (zero or one pad) with 97.8, 97.8 and 91.9% after 2 years. The Litwin score for incontinence (preoperative minus postoperative) was -24, -41 and -63% after 1 month and -13, +3 and -29% after 2 years. Twenty-nine, five and 15 patients had a preoperative five-item version of International Index of Erectile Function (IIEF-5) score of > or = 17 points and a nerve-sparing procedure. After 2 years, 48.1, 0 and 0% had an IIEF-5 score of > or = 17 points without the use of phosphodiesterase type 5 (PDE-5) inhibitors, but when including patients using inhibitors there were no significant differences. CONCLUSIONS: A comparison of morbidity, short-term convalescence and long-term side-effects of different surgical techniques is strongly biased by both the preoperative status of patients and the skill of the surgeons. Overall, we found some differences in the short-term results (e.g. early continence) and comparable long-term results.  相似文献   
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