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排序方式: 共有8185条查询结果,搜索用时 15 毫秒
11.
Merritt W Brown Brenda E Porter Dennis J Dlugos Jeff Keating Andrew B Gardner Phillip B Storm Eric D Marsh 《Clinical neurophysiology》2007,118(8):1744-1752
OBJECTIVE: Interictal spikes in intracranial EEG (iEEG) may correlate with epileptogenic cortex, but review of interictal iEEG is labor intensive. Accurate automated spike detectors are necessary for understanding the role of spikes in epileptogenesis. METHODS: The sensitivity, accuracy and reproducibility of three automated iEEG spike detectors were compared against two human EEG readers using iEEG segments from eight patients. A consensus set of detections was generated for detector calibration. Spike verification was calculated after both human EEG readers independently reviewed all detections. RESULTS: Humans and two of the three automated detectors demonstrated comparable accuracy. In four patients, automated spike detection sensitivity was >70% and accuracy was >50%. In the remaining four patients, EEG background morphology resulted in poorer performance. Blinded human verification accuracy was 76.7+/-6.6% for computer-detected spikes, and 84.5+/-4.1% for human-detected spikes. CONCLUSIONS: Automated iEEG spike detectors perform comparably to humans, but sensitivity and accuracy are patient dependent. Humans verified the majority of computer-detected spikes. SIGNIFICANCE: In some patients automated detectors may be used for mapping spike occurrences in epileptic networks. This may reveal associations between spike distribution, seizure onset, and pathology. 相似文献
12.
M J Gardner 《Journal of the National Cancer Institute. Monographs》1992,(12):133-135
Childhood cancer around nuclear installations has been studied in recent years, particularly in the United Kingdom but also in other countries. The early studies were prompted by the suggestion of a 10-fold raised level of childhood leukemia around the Sellafield nuclear site in England, which was confirmed and followed by the identification of generally smaller excesses around some (but not all) other nuclear sites in the United Kingdom. Marked excesses have not been reported in other countries. The increased leukemia rate around Sellafield has been further investigated by examining individual cases in detail in epidemiological cohort and case-control studies. The raised incidence seems to have been concentrated in children born in the local area but not among children who moved in after birth and was particularly associated with fathers who had experienced higher levels of occupational external ionizing radiation exposure at Sellafield before their children's conception. The underlying cause of this statistical association is not yet clear, but the findings have important potential implications for radiobiology and for protection of radiation workers and their children. 相似文献
13.
Dr. Mark C. Granberry Pharm.D. Dr. Stephanie F. Gardner Pharm.D. Dr. Eric F. Schneider Pharm.D. Dr. Inge R. Carter M.D. 《Pharmacotherapy》1996,16(5):932-936
Study Objective . To determine if one commercial extended-release formulation of nifedipine (Adalat CC) is as effective as another (Procardia XL) in controlling blood pressure over 24 hours. Design . Open-label, randomized, crossover study. Setting . University-affiliated family medicine clinic. Patients . Fifteen patients with stage 1–4 primary hypertension. Interventions . Procardia XL or Adalat CC once/day was titrated to achieve blood pressure control. The effective dose was continued for 4 weeks, washed out for 1 week, and reinstituted with other study drug. Measurements and Main Results . Twenty-four-hour ambulatory blood pressure was recorded the conclusion of each treatment phase. Treatment phases were compared for mean 24-hour blood pressure, mean daytime (6:00 a.m.–10:00 p.m.) and mean nighttime blood pressure, and mean blood pressure load (percentage of blood pressure measurements < 140/90 mm Hg daytime and > 120/80 mm Hg nighttime). Thirteen patients completed the study. No statistically significant difference was seen in mean 24-hour blood pressure (138/86 mm Hg for Procardia XL vs 137/85 mm Hg for Adalat CC), daytime or nighttime blood pressure, or blood pressure load. Two patients experienced clinically significant adverse effects while taking Adalat CC. Conclusions . In these patients with primary hypertension, Adalat CC was as effective as Procardia XL at controlling blood pressure for 24 hours. Blood pressure, heart rate, and adverse effects should be monitored 2–4 weeks after any exchange of Adalat CC for Procardia XL. 相似文献
14.
L M Lichtenberger J W Gardner J C Barreto F H Morriss 《Journal of pediatric gastroenterology and nutrition》1991,13(4):342-346
We investigated the presence of volatile aliphatic amines by fluorescamine and gas chromatographic-head space analysis in human breast milk and amniotic fluid to assess their role in neonatal hypergastrinemia. These volatile nitrogenous amino acid metabolites have been previously demonstrated to stimulate gastrin release in in vivo and in vitro laboratory preparations. In the present study we demonstrated that these gastrin-stimulatory volatile amines were present in significant concentrations in breast milk during the first several weeks after parturition and in amniotic fluid. The individual amines that were identified in both human milk and amniotic fluid samples were methylamine, dimethylamine, ethylamine, trimethylamine, propylamine, isobutylamine, and butylamine. This study provides indirect evidence to support the possibility that the hypergastrinemia measured in the fetus/neonate during the period immediately before and after birth may be attributable, in part, to the ingestion of fluid containing high concentrations of gastrin-stimulating amines. 相似文献
15.
Y. W. Loke A. King T. Burrows L. Gardner M. Bowen S. Hiby S. Howlett N. Holmes D. Jacobs 《Tissue antigens》1997,50(2):135-146
A monoclonal antibody to HLA-G has been generated by immunizing HLA-A2.1/human β2 -microglobulin (β2 m) double transgenic mice with murine L cells transfected with both human β2 m and HLA-G. This monoclonal antibody, designated as G233, has been found not to cross-react with other HLA class I antigens when tested on numerous cell lines by flow cytometry. With immunohistology, all populations of extravillous trophoblast (cell columns, interstitial trophoblast, endovascular trophoblast, placental bed giant cells) were stained. An extensive range of adult and fetal tissues was also tested but none reacted with monoclonal antibody G233, including those previously reported to express HLA-G mRNA, indicating that the protein has a highly restricted distribution. Failure to detect HLA-G in the fetal thymus raises the question as to how T-cell tolerance to this antigen is induced. Immunoprecipitation of trophoblast surface proteins with monoclonal antibody G233 revealed a heavy chain of 39 kDa and a light chain of 12 kDa, indicating that HLA-G expressed on the surface of trophoblast is complexed with p2m. However, sequential immunoprecipitation with monoclonal antibody W6/32 followed by monoclonal antibody G233 continued to detect a residual band of 39 kDa, suggesting that trophoblast surface HLA-G may also occur as free heavy chains not associated with p2m. Immunoprecipitation followed by two dimensional gel electrophoresis showed that monoclonal antibody G233 recognizes several iso-forms of HLA-G from trophoblast similar to the characteristic spot array previously described for HLA-G. This monoclonal antibody G233 will be highly useful in future experiments to elucidate the function of HLA-G. 相似文献
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17.
Revision chronic ear surgery. 总被引:6,自引:0,他引:6
David M Kaylie Edward K Gardner C Gary Jackson 《Otolaryngology--head and neck surgery》2006,134(3):443-450
OBJECTIVE: To report results of revision chronic ear surgery following guidelines of the American Academy of Otolaryngology-Head and Neck Surgery and to establish expectations for infection and cholesteatoma control and hearing outcomes. STUDY DESIGN: Retrospective case review of all patients who underwent revision chronic ear surgery from January 1, 1990 to December 31, 2000. Revision chronic ear surgery included canal wall up and canal wall down procedures with ossicular chain reconstruction performed as needed. Cholesteatoma control, hearing improvement, and closure of middle ear space are main outcome measures. SETTING: Tertiary referral center. RESULTS: Cholesteatoma recurrence rate was 57% at 1 year after surgery and 14% in patients with a minimum of a 5-year follow-up. Disease control was achieved in 96% of patients. Hearing was significantly improved in all surgical groups. Closure of the air-bone gap for revision partial ossicular replacement prosthesis cases (PORP) to less than 20 dB occurred in 50% of patients. Closure of the air-bone gap to within 30 dB for revision total ossicular replacement prosthesis (TORP) occurred in 60% of patients. Canal wall down status had a significant impact on hearing results after PORPs and TORPs; patients with intact canal walls had significantly better hearing results. Diagnosis of cholesteatoma significantly impacted hearing results for TORPs but not PORPS. CONCLUSIONS: Cholesteatoma control rates after revision surgery are similar to primary cases. Significant improvement in hearing can be expected after revision chronic ear surgery. Hearing results after a revision surgery that requires a PORP is worse than primary cases and is canal wall status dependent. Closure of the middle ear space and creation of a safe dry ear can be expected after revision chronic ear surgery. SIGNIFICANCE: This is a review of a large series of exclusively revision chronic ear surgery. EBM rating: C-4. 相似文献
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20.
E M Berke A W Gardner M I Goran E T Poehlman 《The American journal of clinical nutrition》1992,55(3):626-629
We examined the effect of pretesting environment on measurement of resting metabolic rate (RMR). RMR was measured in 18 older (66.1 +/- 1.4 y) individuals after an overnight stay in the Clinical Research Center (ie, inpatient) and after subjects transported themselves to the laboratory (ie, outpatient). Similar measurements were also performed after an 8-wk endurance-training program. RMR was higher (P less than 0.01) before exercise training in subjects who transported themselves to the laboratory (ie, outpatients; 4.9 +/- 0.13 kJ/min) than in inpatients (4.6 +/- 0.13 kJ/min) and after exercise training in outpatients (5.4 +/- 0.08 kJ/min) vs inpatients (5.0 +/- 0.13 kJ/min). Training increased RMR under both inpatient (10%; P less than 0.01) and outpatient (11%; P less than 0.01) conditions. We conclude that RMR is higher when measured under outpatient conditions in older volunteers. Therefore, when daily energy requirements based on the assessment of RMR are being estimated, the pretesting environment should be considered. However, the exercise-training-induced increase in RMR can be detected by using either an inpatient or an outpatient protocol. 相似文献