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41.
PURPOSE: This study examined the effects of age on recovery of peak torque of knee extensors (PTEX) and flexors (PTFL), and total work (TW) during high-intensity intermittent 30-s (HI30) and 60-s (HI60) exercise in boys (N=19; age, 11.4+/-0.5 yr), teens (N=17; age, 14.7+/-0.4 yr), and men (N=18; age, 24.1+/-2.0 yr). METHODS: Each age group's subjects were subdivided to participate in an HI30 or an HI60 protocol. The HI30 involved 4x18 maximal knee extensions and flexions (1-min rest between sets), and the HI60 comprised of 2x34 reps (2-min rest). PTEX (N.m.kg), PTFL (N.m.kg), and TW (J.kg) were recorded at each set. The percent recovery of PTEX, PTFL, and TW was calculated as percent of the value achieved in the first set. RESULTS: In HI60, the percent recovery for PTEX, PTFL, and TW after the first set was higher in boys compared with teens and men (P<0.01). In HI30, the percent recovery for PTEX, PTFL, and TW was higher in boys compared with men in all sets (P<0.01), and in teens compared with men in the last two sets (P<0.05). The percent recovery of PTFL and TW was higher in boys compared with teens in the last two sets (P<0.05). Lactate increase was most pronounced in men, less pronounced in teens, and least pronounced in boys (P<0.01). Heart rate recovered faster in boys compared with teens and men in both protocols (P<0.05). CONCLUSIONS: The recovery was faster in boys than in teens and men during HI30 and HI60, as evident by the greater percent recovery in boys for a given time. Furthermore, it appears that the rate of recovery during HI30 and HI60 anaerobic exercise is maturity dependent.  相似文献   
42.
INTRODUCTION: Electronic interactive learning environments can enhance the learning experience and may prove beneficial in basic life support (BLS) training. As part of the European Union funded project "JUST-in-time health emergency interventions-training of non-professionals by virtual reality and advanced IT tools", an innovative interactive CD-ROM on BLS and other emergency medicine topics was developed. We hypothesised that individuals without previous BLS training could learn CPR techniques from this CD. METHODS: Sixty-two students were randomised into a group studying the JUST CD in a computer class room for up to 60 min, and a control group who did not receive any training (serving as a reference). CD users also completed a satisfaction questionnaire immediately after studying the CD. The BLS skills of both groups were assessed in a mock BLS scenario on a training manikin. BLS performance was video recorded and analysed. RESULTS: After studying the CD for a mean period of 42 min, users of the CD had better assessment skills and were more likely to show a positive helping attitude, but chest compression and breathing techniques were ineffective. Most users rated the CD as very good and a positive learning tool. CONCLUSION: Individuals without prior BLS training showed improved behaviour and assessment skills after exposure to the CD, but motor skill acquisition requires alternative learning strategies.  相似文献   
43.
An open, two-period, randomized, crossover trial of two lisinopril (1-[N2-[(S)-1-carboxyl-3-phenylpropyl]-L-lysil]-L-proline, CAS 76547-98-3) formulations (Adicanil as test and another commercially available preparation as reference) was performed in 24 healthy volunteers. A single 20 mg oral dose of lisinopril was administrated and pharmacokinetic parameters were compared. Lisinopril plasma concentrations were measured by a fully validated LC-MS method. The parametric 90% confidence intervals of the geometric mean values of the test/reference ratios were 95.38% to 105.94% (point estimate: 100.52%) for AUC(0-last), 94.01% to 103.47% (point estimate: 98.63%) for AUC(0-infinity) and 92.34% to 103.97% (point estimate: 97.98%) for Cmax, being within the acceptance criteria for bioequivalence (80%-125%). T(1/2), k(el) and Tmax values were also tested and the difference was not statistically significant. Therefore, it is concluded that the test and the reference lisinopril formulations are bioequivalent both in the extent and the rate of absorption.  相似文献   
44.
Relationships between Cloninger's temperament and character dimensions and plasma sex hormone levels and biogenic amine turnover were studied in male prison inmates convicted of rape (n=61) or child molestation (n=24) and normal male controls (n=25). The participants completed the Temperament and Character Inventory (TCI), which includes the temperament dimensions Novelty Seeking, Harm Avoidance, Reward Dependence and Persistence as well as the character dimensions Self-Directedness, Cooperativeness and Self-Transcendence. Plasma levels of testosterone, dihydrotestosterone, sex hormone binding globulin, luteinizing hormone (LH) and follicle-stimulating hormone were estimated in plasma samples and 5-hydroxyindoleacetic acid (5-HIAA), homovanillic acid (HVA), and 3-methoxy-4-hydroxyphenylglycol (MHPG) in urine samples. Both sex offender groups had higher Novelty, Seeking and lower Reward Dependence, Self-Directedness and Cooperativeness scores compared with the controls. Plasma levels of testosterone and dihydrotestosterone were significantly higher in rapists than in controls. Novelty Seeking scores were positively correlated with LH levels in rapists, and with testosterone levels in child molesters. Harm Avoidance scores were negatively correlated with 5-HIAA levels in rapists and with HVA levels in child molesters. In rapists, the calculated free androgen index showed a negative correlation with 5-HIAA. For the sex offender sample as a whole, the subgroup with high testosterone levels had higher Harm Avoidance scores, the subgroup with low HVA levels had lower Cooperativeness scores, and the subgroups with high 5HIAA or MHPG levels had lower Persistence scores. The results indicate that Novelty Seeking behavior in the group of rapists is associated with a hyperactive hypothalamic-pituitary-gonadal axis. In addition, low serotonin turnover and low dopamine turnover seem to be associated with a passive-avoidant behavioral style in rapists and child molesters, respectively.  相似文献   
45.
We have investigated the role of the allylic 7-ketone in oxidized Delta5-steroids on antileukemic activity. We synthesized and studied a series of oxidized and non-oxidized steroidal esters of p-N,N-bis(2-chloroethyl)aminophenylacetic acid (PHE), chlorambucil's active metabolite. In a comparative study of these 7-keto derivatives, on a molecular basis, regarding their ability to induce sister chromatid exchanges (SCEs) and to inhibit cell proliferation in normal human lymphocytes in vitro, the results with these 7-keto derivatives, on a molecular basis, correlated well with their antileukemic potency against leukemia P388- and L1210-bearing mice, which proved to be significantly increased compared to that of the non-oxidized derivatives. Our results indicate that the role of the steroidal skeleton it is not only for the transportation of the alkylating agent into the cell, but also contributes directly to the mechanism of antileukemic action, by an as-yet unknown way. The main conclusion from this study is that the existence of the allylic 7-keto group in the skeleton of the Delta5-steroidal esters impressively enhances their antileukemic activity, while the toxicity remains at clinically acceptable levels, suggesting that this structural modification should be further investigated.  相似文献   
46.
47.
The present case report describes a patient with Klippel-Feil anomaly (KFA) and oligodontia, carrying a de novo pericentric inversion of chromosome 2 (p12q34). KFA is characterised by congenital vertebral fusion of the cervical spine and a wide spectrum of associated anomalies. It therefore constitutes a heterogenous group of clinical conditions and has been classified morphologically, although its aetiology remains unclear. We present an 18-year-old female with KFA, associated with congenital impairment of hearing, psychomotor retardation, speech limitation, short stature, spinal scoliosis, facial asymmetry and latent hypothyroidism. No renal anomaly or heart disease was present. In addition, she exhibited oligodontia of both the deciduous and permanent dentition, a unique characteristic that has not yet been reported in any non-cleft palate KFA case. Conclusion:the current report of a patient with oligodontia and an inversion on chromosome 2 may aid in the identification of novel genes for oligodontia.Abbreviation KFA Klippel-Feil anomaly  相似文献   
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49.
The aim of the present study was to assess androgen plasma levels and biogenic amine metabolites in a sex-offender group as well as to investigate the relationship between the biological findings and the impulsive, aggressive, and suicidal profile of the offenders. Fifty-seven males convicted for rape and 25 normal males comprised the study sample. We found that although both testosterone levels and aggression-impulsivity scores were higher in the group of rapists, testosterone levels were not associated with the aggression and impulsivity scores. Nevertheless, aggression-impulsivity scores were clearly associated with luteinizing hormone levels. This association may indicate a hyperactive hypothalamic-pituitary-gonadal axis, possibly the result of a reduced serotonergic activity.  相似文献   
50.
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