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991.
Caffeine: sleep and daytime sleepiness   总被引:1,自引:0,他引:1  
Caffeine is one of the most widely consumed psychoactive substances and it has profound effects on sleep and wake function. Laboratory studies have documented its sleep-disruptive effects. It clearly enhances alertness and performance in studies with explicit sleep deprivation, restriction, or circadian sleep schedule reversals. But, under conditions of habitual sleep the evidence indicates that caffeine, rather then enhancing performance, is merely restoring performance degraded by sleepiness. The sleepiness and degraded function may be due to basal sleep insufficiency, circadian sleep schedule reversals, rebound sleepiness, and/or a withdrawal syndrome after the acute, over-night, caffeine discontinuation typical of most studies. Studies have shown that caffeine dependence develops at relatively low daily doses and after short periods of regular daily use. Large sample and population-based studies indicate that regular daily dietary caffeine intake is associated with disturbed sleep and associated daytime sleepiness. Further, children and adolescents, while reporting lower daily, weight-corrected caffeine intake, similarly experience sleep disturbance and daytime sleepiness associated with their caffeine use. The risks to sleep and alertness of regular caffeine use are greatly underestimated by both the general population and physicians.  相似文献   
992.
993.
Background:  Central venous cannulation in young children is technically difficult and may lead to potentially serious complications especially when performed blindly or using anatomical landmarks only.
Aim:  The aim of this study was to determine the anatomical relationship of the internal jugular vein (IJV) and the common carotid artery (CA) in preschool children using ultrasound.
Methods:  Forty five children aged 60 months and under were included prospectively and divided into three groups: group 1: <6 months, group 2: 7–18 months and group 3: 19–60 months. With the head in neutral position the location of the left and right IJV was noted as anterior (A), anterolateral (AL), lateral (L) or medial (M) in relation to the CA at the level of the cricoid cartilage. Depths of IJV and CA as well as time taken to locate the vessels were recorded.
Results:  The IJV was more commonly found in the AL position in all groups. The mean depth was 0.96 cm in group 1, 0.95 cm in group 2 and 3. Mean duration for localization of the vessels was 4.2 s in group 1, 4 s in group 2 and 4.3 s in group 3. The differences between the groups were not significant.
Conclusion:  This study demonstrates that the IJV cover the CA in the majority of young children. Depth of the IJV is rarely more than 1 cm deep to the skin. Ultrasound location of the IJV and CA is easy and does not necessarily delay the procedure. The findings of this study support the use of ultrasound guidance for CVC in children.  相似文献   
994.
995.
OBJECTIVE: To evaluate the results and the feasibility of the technique of percutaneous closing of patent foramen oval (PFO) with Atrial Septal Aneurysm (ASA) among young patients having presented a cryptogenic cerebral ischemia. PATIENTS AND METHODS: Eighteen patients: 14 cryptogenic stroke and 4 TIA with a broad PFO (rank III) and an important ASA (excursion higher than 15 mm) at transesophageal echocardiography (TEE). The average age is 48.2 years: man 61%, women 39%. The patients have little cardiovascular risk factor (0.83/patient) and 38% presented recurrent thromboembolic events. Percutaneous closing is carried out under general anaesthesia with TEE and Amplatzer devices implantation. A control TEE is carried out 6 months after closing. RESULTS: No complication occurred at the time of the procedures. After 72 hours, one patient presented a major complication: one arteriovenous fistula requiring a surgery. Five patients presented a minor complication: two non complicated femoral hematoma, two atrial arrhytmias and one asymptomatic secondary displacement of the device without need for surgery. Seven-teen patients had TEE at six months: the shunt disappeared for 95% from the patients, no thrombus was found. No recurrent thromboembolic event appeared for the 18 patients (median follow-up 19.2 months). CONCLUSION: The installation of a technique of percutaneous closing of the PFO+ASA is safe and effective.  相似文献   
996.
This study evaluated the hospital outcome of octogenarian patients treated by primary angioplasty for acute myocardial infarction less than 12 hours. The long-term mortality and social outcome were evaluated, social outcome was based on IADL and IADL-E scales corresponding to physical autonomy and level of dependence. We included from 1999 to 2005 47 old patients of 83.5+/-3.2 years. The reperfusion of the obstructed coronary artery was obtained in 45 patients (95.7%) with TIMI 3 flow. Hospital mortality was 25.5% and 4.2% without hemodynamic complication. A multivariate analysis identified a Killip score>1 as predictive factor of hospital mortality (OR=8.9 and p=0.05). The long-term survival without death with a follow-up of 26.3+/-18.3 months was 82.2% at 24 months and 70.6% at 48 months according to the Kaplan-Meier method. In an multivariate analysis, hospitalization exit without aspirine was associated with a higher long term mortality (OR=34.8 and p=0.04). According to the evolution of scores of IADL and IADL-E scales, patients had an excellent autonomy and good capacities before the infarction and they kept them on the long term. Thus octogenarians with acute myocardial infarction treated by primary angioplasty have a high in hospital and long term mortality but the survivors preserve an excellent daily autonomy.  相似文献   
997.
Radiofrequency ablation of superficial and perforator veins for venous insufficiency has emerged as a leading alternative to traditional vein stripping operations. This percutaneous technique can be performed in less than an hour using local anesthetic or sedation. The VNUS Closure catheters (VNUS Medical Technologies, San Jose, California) work by resistive heating in the vein wall that is constantly monitored through a feedback loop to the VNUS Closure generator. Side effects are less than with other endovenous ablation techniques and patients resume normal activity immediately. The new ClosureFAST catheter is an important advancement that combines the speed of endovenous laser ablation with the expected fewer side effects of radiofrequency ablation.  相似文献   
998.
Roth J  Sagie B  Szold A  Elran H 《Surgical neurology》2007,68(2):177-84; discussion 184
BACKGROUND: Ventriculoperitoneal shunts and distal shunt revisions bear a high risk of distal malfunction, especially in patients with previous abdominal pathologies as well as in obese patients. We performed laparoscopy-guided distal shunt placement or revision for patients with and without a positive abdominal history. We review the indications, techniques, complications, and long-term outcomes of these cases and compare the results to those of patients operated without laparoscopic guidance. METHODS: A total of 211 distal shunt procedures were performed in our institute between January 2001 and December 2005, 59 of which were laparoscopically guided, and 152 were not. Of the 211 procedures, 177 were placement of new shunt systems, and 34 were distal revisions. A total of 33 procedures were performed in 25 patients with a history of abdominal surgery or inflammatory bowel disease; 15 procedures were operated with laparoscopic guidance. RESULTS: The short-term complication and outcome rates were similar between the laparoscopy group and the other patients. Among the patients with new shunts, the long-term distal malfunction rate was lower in the laparoscopy group compared with the nonlaparoscopy group (4% vs 10.3%, respectively; P = .17). No patients in the laparoscopy group and 6 patients operated by other techniques had distal malfunction. There was 1 laparoscopy-related mortality and no morbidity. CONCLUSIONS: Laparoscopy is not routinely indicated in distal shunt placement or revision. However, a laparoscopy-guided procedure may lower the rate of distal malfunction in patients with previous abdominal surgeries.  相似文献   
999.
Sleep and cognitive (memory) function: research and clinical perspectives   总被引:8,自引:0,他引:8  
The field of memory and sleep is controversial and extremely interesting, and the relationships between thought processes, i.e. cognition and sleep, have recently been examined in a variety of clinical and basic research settings, as well as being the object of intense interest by the general public. For example, there are data which demonstrate that insomnia, as well as specific sleep disorders, can have a negative impact on sleep cognition as well as affect daytime patterns of cognitive functioning. Thus, sleep, disturbed sleep and the lack of sleep appear to affect cognitive and memory functions. An International Workshop dealing with Sleep and Cognitive Function: Research and Clinical Perspectives was convened in Cancún, Mexico, 1-4 March 1999 under the auspices of the World Health Organization Worldwide Project on Sleep and Health and the World Federation of Sleep Research Societies. A great number of areas of intersection between sleep and cognitive function were examined during the course of the Workshop, such as aging, cognition and sleep and the dream process and sleep. The results of these discussions are included in a WHO publication (WHO Doc.: MSD/MBD/00.8). In the present report we concentrate on presenting a summary of a coherent set of data which examine memory consolidation during sleep and the impact of insomnia on cognitive functions. Based upon these data, a review of memory and drug effects that are sleep-related, and an examination of the relationship between hypnotics and cognitive function are included. Finally, a summary of recommendations of the Workshop participants is presented.  相似文献   
1000.
Hypotension is a frequent complication of spinal anaesthesia for caesarean section and can threaten the well-being of the unborn child. Numerous randomised controlled trials (RCTs) dealt with measures to prevent hypotension. The aim of this study was to determine the reporting quality of RCTs using the Consolidated Standards of Reporting Trials (CONSORT) statement since low quality can lend false credibility to a study and overestimate the effect of an intervention. We performed a systematic literature search in PubMed to identify relevant RCTs in a pre-CONSORT period (1990–1994) and a post-CONSORT period (2004–2008). A comparative evaluation was done between the two periods, and the trials were assessed for compliance with each of the 22 CONSORT items. A total of 37 RCTs was identified. The CONSORT score increased significantly (p < 0.05) from 66.7% (±12.5%) in the pre-CONSORT period to 87.4% (±6.9%) in the post-CONSORT period. A statistically significant improvement was found for eight items, including randomization, blinding and intention-to-treat analysis. The CONSORT score in the post-CONSORT era was fairly good, also in comparison to other medical fields. In the post-CONSORT era, reporting of important items improved, in particular in the domains that are crucial to avoid bias and to improve internal validity. Use of CONSORT should be encouraged in order to keep or even improve the reporting quality.  相似文献   
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