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排序方式: 共有843条查询结果,搜索用时 31 毫秒
21.
DANIEL F. KRIPKE ELIZABETH K. HAHN ALEXANDRA P. GRIZAS KEP H. WADIAK RICHARD T. LOVING J. STEVEN POCETA FARHAD F. SHADAN JOHN W. CRONIN LAWRENCE E. KLINE 《Journal of sleep research》2010,19(4):612-619
Wrist actigraphy is employed increasingly in sleep research and clinical sleep medicine. Critical evaluation of the performance of new actigraphs and software is needed. Actigraphic sleep–wake estimation was compared with polysomnographic (PSG) scoring as the standard in a clinical sleep laboratory. A convenience sample of 116 patients undergoing clinical sleep recordings volunteered to participate. Actiwatch‐L recordings were obtained from 98 participants, along with 18 recordings using the newer Spectrum model (Philips Electronics), but some of the actigraphic recordings could not be adequately aligned with the simultaneous PSGs. Of satisfactory alignments, 40 Actiwatch recordings were used as a training set to empirically develop a new Scripps Clinic algorithm for sleep–wake scoring. The Scripps Clinic algorithm was then prospectively evaluated in 39 Actiwatch recordings and 16 Spectrum recordings, producing epoch‐by‐epoch sleep–wake agreements of 85–87% and kappa statistics averaging 0.52 (indicating moderate agreement). Wake was underestimated by the scoring algorithm. The correlations of PSG versus actigraphic wake percentage estimates were r = 0.6690 for the Actiwatch and r = 0.2197 for the Spectrum. In general, using a different weighting of activity counts from previous and subsequent epochs, the Scripps Clinic algorithm discriminated sleep–wake more successfully than the manufacturer’s Actiware algorithms. Neither algorithm had fully satisfactory agreement with PSG. Further evaluations of algorithms for these actigraphs are needed, along with controlled comparisons of different actigraphic designs and software. 相似文献
22.
DANIEL J. COHEN AMY BEGLEY JENNIE J. ALMAN DAVID J. CASHMERE REGINA N. PIETRONE ROBERT J. SERES ANNE GERMAIN 《Journal of sleep research》2013,22(1):76-82
Sleep disturbances are a hallmark feature of post‐traumatic stress disorder (PTSD), and associated with poor clinical outcomes. Few studies have examined sleep quantitative electroencephalography (qEEG), a technique able to detect subtle differences that polysomnography does not capture. We hypothesized that greater high‐frequency qEEG would reflect ‘hyperarousal’ in combat veterans with PTSD (n = 16) compared to veterans without PTSD (n = 13). EEG power in traditional EEG frequency bands was computed for artifact‐free sleep epochs across an entire night. Correlations were performed between qEEG and ratings of PTSD symptoms and combat exposure. The groups did not differ significantly in whole‐night qEEG measures for either rapid eye movement (REM) or non‐REM (NREM) sleep. Non‐significant medium effect sizes suggest less REM beta (opposite to our hypothesis), less REM and NREM sigma and more NREM gamma in combat veterans with PTSD. Positive correlations were found between combat exposure and NREM beta (PTSD group only), and REM and NREM sigma (non‐PTSD group only). Results did not support global hyperarousal in PTSD as indexed by increased beta qEEG activity. The correlation of sigma activity with combat exposure in those without PTSD and the non‐significant trend towards less sigma activity during both REM and NREM sleep in combat veterans with PTSD suggests that differential information processing during sleep may characterize combat‐exposed military veterans with and without PTSD. 相似文献
23.
BENJAMIN J. PIETERS DO EDWARD PENN MD PAMELA NICKLAUS MD DANIEL BRUEGGER MD BHAVI MEHTA BA ROBERT WEATHERLY MD 《Paediatric anaesthesia》2010,20(10):944-950
Background: Emergence delirium (ED) is a frequent postoperative complication in young children undergoing ENT procedures and it may be exacerbated by sevoflurane anesthesia whereas propofol maintenance has been suggested to decrease the incidence of ED. The aim of this randomized, prospective, double‐blind study was to evaluate the effect of sevoflurane vs propofol anesthesia on the quality of recovery after adenotonsillectomy. Methods: Forty‐two patients were randomized to maintenance with either propofol or sevoflurane for adenotonsillectomy. At the conclusion of surgery, patients were extubated awake. ED and pain were assessed using the Pediatric Anesthesia Emergence Delirium (PAED) and the Children’s Hospital of Eastern Ontario Scale (CHEOPS), respectively. Higher PAED scores (0–20) indicate greater severity of ED. Nursing and parental satisfaction, hospital length of stay, postoperative nausea and vomiting (PONV), anesthetic complications, and subsequent emergency room admissions were also assessed. Results: Median PAED score was 14 in the propofol group and 17 in the sevoflurane group (NS). Propofol was associated with less pain medication required during recovery and a lower incidence of PONV (5.3% vs 36.8%, P < 0.05). Nursing and parental satisfaction as well as time spent in recovery room was similar for the two groups. Conclusion: Propofol anesthesia does not influence agitation after adenotonsillectomy, as measured by the PAED score. A PAED score of ≥10 was not useful in identifying patients with ED. However, propofol maintenance is associated with less need for pain medication in the recovery room and a lower incidence of PONV compared to sevoflurane anesthesia. 相似文献
24.
Irshad Ahammed A. SHAIKH Harun THOMAS Kishore JOGA A. Ibrahim AMIN Thomas DANIEL 《Journal of digestive diseases》2009,10(3):207-212
OBJECTIVE: While major bile duct injury is the most serious complication following laparoscopic cholecystectomy, bile leak from the cystic duct stump remains the commonest morbidity. This is a retrospective assessment of all patients who had a cholecystectomy over a 5‐year period from April 2003 to March 2008. METHODS: Data related to bile leakage were obtained from the Unisoft endoscopic retrograde cholangio‐pancreatography (ERCP) database. RESULTS: Overall 2011 cholecystectomies were performed, of which 488 were done as emergency procedures. Thirteen patients had significant bile leakage, three of which were from accessory ducts, in one the source could not be identified and nine had a cystic duct stump leak (CDSL), which formed the basis of this study. Eight of the nine CDSL patients had successful ERCP and stenting. One had a percutaneous trans‐hepatic cholangiography and stenting. CDSL following emergency laparoscopic cholecystectomy was up to threefold higher than after elective procedures. CONCLUSION: The CDSL of 0.44% was comparable to the reported incidence in the literature. Endoscopic management remains the treatment of choice. Emergency cholecystectomies seem to have a higher incidence of CDSL. 相似文献
25.
1. Three cases of hereditary hemolytic disease secondary to G-6-PD deficiency are described. Two of the cases were first cousins of Scotch-Irish-English descent and the mode of inheritance was believed to be sex-linked.The third case was of Turkish origin; no family studies were availale.2. The mothers, who were heterozygous for G-6-PD deficiency, showed onlyminimal expression of the defect, which was manifested by a slightly decreasedred cell survival in both mothers and an abnormal methemoglobin reductiontest in one of them.3. All three cases showed a more pronounced fall in erythrocyte ATP afterincubation with phenylhydrazine than that observed in primaquine-sensitiveNegroes whose red cells were less deficient in G-6-PD.4. It is suggested that the inability of the G-6-PD-deficient erythrocyte tomaintain adequate levels of ATP may be an important factor in the pathogenesis of the hemolytic process. Submitted on August 26, 1963 Accepted on October 24, 1963 相似文献
26.
27.
Previous study by the current authors has shown that treating homes with D'Allergen, an acaricidal agent, can reduce bronchial hyper-reactivity in asthmatic children with house dust mite allergy. In the present study, the effects of a single D'Allergen treatment on the levels of major dust mite allergens, Der p I and Der f I was evaluated, and the duration of its effectiveness in the environment determined. Twenty randomly selected homes were treated with the acaricide and ten remained untreated. Dust samples were collected from mattresses, upholstered sofas and carpets of these homes before and 1, 2 and 4 months after treatment. The samples were then assayed for Der p I and Der f I allergens using a sandwich enzyme immunoassay. The results showed that D'Allergen was effective in reducing dust mite allergen levels in all three niches by 1.5–22.3 times below baseline values. This effect, however, was only present for 2 months, and the dust mite allergen levels increased to those of the baseline by the fourth month after treatment. These results indicated that repeated applications of the acaricide were required at 2–3 monthly intervals to obtain optimal effectiveness. 相似文献
28.
Working memory and preparation elicit different patterns of slow wave event-related brain potentials 总被引:8,自引:0,他引:8
DANIEL S. RUCHKIN HOWARD L. CANOUNE RAY JOHNSON Jr. WALTER RITTER 《Psychophysiology》1995,32(4):399-410
Some event-related brain potential (ERP) studies of working memory have used delayed match-to-sample designs in which a stimulus (S1) is held in memory for comparison with a subsequent stimulus (S2). During the S1-S2 interval, ERP slow negativities varied with both the type and amount of material held in working memory. One interpretation is that these slow waves index working memory operations. An alternative explanation is that they only reflect general preparatory processing for the response to S2. To decide between these explanations, we used two visual processing tasks that required similar preparation for S2. In one task, visual memory rehearsal operations were required. During the S1-S2 interval, there were clear differences between the amplitudes, topographies, and the effect of information load on the slow waves in the two tasks, thus ruling out preparation only as an explanation. 相似文献
29.
Steroid Hormone Metabolism in Chronic Myelogenous Leukemia 总被引:1,自引:0,他引:1
Individual metabolites of steroid hormones were isolated and measuredfrom the urine of patients with chronic myelogenous leukemia. The resultswere compared with earlier studies of patients with chronic lymphatic leukemia, men with prostatic cancer, women with breast cancer and normalmen and women. The metabolites of hydrocortisone were in the normal rangefor the patients with chronic myelogenous leukemia but the amount of tetrahydrocortisol was generally greater than that of tetrahydrocortisone. Therewas no evidence for a sex difference in the production of these metabolites.The tentative conclusion was drawn that metabolites of the "adrenal androgens" were also in the normal range in chronic myelogenous leukemia. Theseresults contrast with those in chronic lymphatic leukemia patients where asex difference in production of hydrocortisone was evident and the metabolitesof "adrenal androgens" were at low levels in both sexes. Submitted on August 13, 1964 Accepted on September 20, 1964 相似文献
30.