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Sun exposure in childhood is 1 of the risk factors for developing skin cancer, yet little is known about levels of exposure at this age. This is particularly important in countries with high levels of ultraviolet radiation (UVR) such as Australia. Among 49 children 3 to 5 years of age attending child care centers, UVR exposure was studied under 4 conditions in a repeated measures design; sunny days, cloudy days, teacher’s instruction to stay in the shade, and a health professionals instruction to apply sunscreen. Three different data collection methods were employed: (a) completion of questionnaire or diary by parents and researcher, (b) polysulphone dosimeter readings, and (c) observational audits (video recording). Results of this study indicated that more than half the children had been sunburnt (pink or red) and more than a third had experienced painful sunburn (sore or tender) in the last summer. Most wore short sleeve shirts, short skirts or shorts and cap, that do not provide optimal levels of skin protection. However, sunscreen was applied to all exposed parts before the children went out to the playground. Over the period of 1 hr (9–10 a.m.) the average amount of time children spent in full sun was 22 min. On sunny days there was more variation across children in the amount of sun exposure received. While the potential amount of UVR exposure for young children during the hour they were outside on a sunny day was 1.45 MED (Minimum Erythemal Dose), they received on average 0.35 MED, which is an insufficient amount to result in an erythemal response on fair skin even without the use of sunscreen.  相似文献   
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Laparoscopic appendectomy in children is a generally accepted procedure for the treatment of non-complicated acute appendicitis. Nevertheless, the role of laparoscopy in complicated appendicitis is more controversial. The objective of this study was to examine the safety, efficacy and complications of laparoscopy in children with complicated appendicitis. This is a retrospective review of the children who underwent laparoscopic appendectomy for complicated appendicitis at King Khalid University Hospital, Riyadh, Saudi Arabia between January 1998 and March 2006. Complicated appendicitis includes perforated appendicitis, gangrenous appendicitis and appendicular masses found intra-operatively. Data collected include demographic, duration of symptoms, operative time, analgesia, complications, length of hospitalization and histopathology. Laparoscopic appendectomy was done by three trocar technique in all cases. During the study period, 59 children aged 3–12 years underwent laparoscopic appendectomy for complicated appendicitis. There were 34 patients with perforated appendicitis, 12 patients with gangrenous appendicitis and 13 patients with appendicular mass. The average operating time was 62 min. The average length of hospitalization was 5 days. The post-operative narcotic analgesic requirement was minimal. Laparoscopy was converted to open surgery in two patients (3.38%). These two cases were excluded from further analysis. Four out of 57 patients (7.01%) had post-operative complications. Three patients (5.26%) developed wound infection. One patient (1.75%) developed haematoma at umbilical port site. There was no post-operative intra-abdominal collection. Laparoscopic appendectomy is a safe alternative for the treatment of complicated appendicitis. It does not increase the incidence of complications even with complicated appendicitis. Contrary to the previous studies, we did not have increased incidence of intra-abdominal collection in this review. However, prospective randomized controlled trials are needed to verify these findings.  相似文献   
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This report describes the relationship between monoamines, sleep and seizures before and 1-month after amygdala kindling in young cats (<1 year old; n=8; six female and two male). Concentrations (fmoles of norepinephrine or NE, dopamine or DA and serotonin or 5-HT) were quantified in consecutive, 5-min microdialysis samples (2 microl/min infusion rate) from amygdala and locus ceruleus complex (LC) during four, 6-8-h polygraphic recordings before (n=2) and 1 month post-kindling (n=2); 5-min recording epochs were temporally adjusted to correspond to dialysate samples and differentiated according to dominant sleep or waking state (lasting > or =80% of 5-min epoch) and degree of spontaneous seizure activity (number and duration of focal versus generalized spikes and spike trains and behavioral seizure correlates). Post-kindling records in each cat were divided into two groups (n=1 record each) based on higher or lower spontaneous EEG and behavioral seizure activity and compared to pre-kindling records. We found: (1) before and after kindling, NE and 5-HT but not DA concentrations were significantly lower in sleep than waking at both sites; (2) after kindling, each cat showed cyclic patterns, as follows: (a) higher NE, 5-HT and DA concentrations accompanied increased seizure activity with delayed sleep onset latency and increased sleep fragmentation (reduced sleep state percentages, number of epochs and/or epoch duration) in one recording versus (b) lower monoaminergic concentrations accompanied reduced seizure activity, rapid sleep onset and reduced sleep disruption in the other recording. The alternating, post-kindling pattern suggested "rebound" effects which could explain some controversies in the literature about chronic effects of kindling on monoamines and sleep-waking state patterns.  相似文献   
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We used microdialysis to determine extracellular concentrations of norepinephrine (NE), dopamine (DA) and serotonin (5-HT) before and during a 1-day amygdala kindling paradigm. Subjects were young cats (<1 year old; n=8; 6 female, 2 male). Consecutive 5-min samples (2 microl/min infusion rate) were obtained from left amygdala and ipsilateral locus ceruleus complex (LC) under 3 experimental conditions lasting 1-h each (n=12 samples per cat per condition): (1) just before amygdala stimulation (baseline), (2) during focal afterdischarge (AD) and (3) during generalized AD. ADs were elicited by electrical stimulation applied to establish thresholds immediately before dialysate collection as well as during each sample collected in focal vs. generalized AD conditions. Sample concentrations were time-adjusted to correspond with sleep vs. waking state and/or focal vs. generalized ADs. Seizure activity was indexed by AD threshold (mA) and duration (s) as well as number and duration of specific clinically evident (behavioral) seizure manifestations. Main results were: (1) Lower baseline concentrations (fmoles per sample) of NE, DA and 5-HT correlated with subsequent increases in duration of focal and generalized AD as well as number of behavioral seizure correlates. (2) When compared to baseline levels, NE, DA and 5-HT concentrations significantly increased only in amygdala during focal AD and in both amygdala and LC during generalized AD. (3) NE and 5-HT concentrations were higher than DA at both collection sites and were selectively associated with increased wakefulness throughout the study.  相似文献   
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ABSTRACT

This article aims at identifying a threshold number of drinks per day beyond which there is a high risk of developing alcoholic behavior that would enable physicians to more confidently support the use of alcohol for cardiovascular risk prevention. In a randomly selected, population-based sample of 2,042 adults 45 years or older, we graded alcohol drinking behavior using the Self-Administered Alcoholism Screening Test, quantified alcohol amount by questionnaire, and assessed the prevalence of cardiovascular disease (coronary, peripheral, or cerebrovascular disease) by medical record review. Although optimal alcohol use (≤2 drinks/day) was associated with reduced odds of cardiovascular disease, 43% of alcoholics and 82% of problem drinkers reported alcohol use in the optimal range as well. The association of alcohol use in the optimal range with alcohol-related behavioral problems supports the reluctance in physicians from recommending alcohol use for cardiovascular benefit, not withstanding the underreporting of alcohol use by alcoholics.  相似文献   
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Objective

Traditionally vascular rings in infants and children are treated through an open thoracotomy. Recently, thoracoscopic surgery has been used for these complex procedures. This study reports our early experience with thoracoscopic division of vascular rings and evaluates the efficacy and safety of this approach.

Material and Methods

Patients who underwent thoracoscopic division of vascular rings at King Khalid University Hospital, Riyadh, Saudi Arabia, from December 2004 to January 2006 are included. Their data were carefully analyzed looking at demographics, clinical presentation, diagnostic modality, type of the anomaly, operative details, complications, and outcome.

Results

A total of 9 patients underwent thoracoscopic division of vascular rings. Age at surgery ranged between 2 and 108 months (mean, 24 months). Weight varied between 5.3 and 32 kg (mean, 10.3 kg). All patients were symptomatic. Computed tomographic scan was diagnostic and accurately defined the type of anomaly in all the patients. Four patients had a right aortic arch with an aberrant left subclavian artery and left ductus/ligamentum arteriosum, 2 had double aortic arches, and 3 had a right aberrant subclavian artery. One patient developed right-sided pneumothorax on the contralateral site, and another one developed apnea 12 hours after surgery, requiring mechanical ventilation. There was no mortality. Operative time ranged between 50 and 145 minutes, the mean being 107 minutes. The average hospital stay was 4 days. Five patients had their preoperative symptoms completely resolved, and the rest are showing steady improvement. The average follow-up period is 6 months.

Conclusion

Our early experience indicates that thoracoscopic division of vascular rings is safe and effective. Because it takes away the need for thoracotomy, it is likely that it can result in less postoperative pain and rapid convalescence. It also prevents the ill effects of thoracotomy and gives good cosmetic results.  相似文献   
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