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31.
OBJECTIVE: A robust and fast algorithm for the offline detection of epileptic seizures in scalp EEG is described. It is aimed for seizure detection with high sensitivity and low number of false detections in long-term EEG data without a priori information. METHODS: To capture the characteristic electrographic changes of seizures, we developed an efficient method based on power spectral analysis techniques. The integrated power is calculated in two frequency bands for three multi-channel seizure detection montages (referenced against the average of Fz-Cz-Pz, common average, bipolar) using the same parameters for all montages and all patients taking into account an appropriate artifact rejection. RESULTS: A total of 3248 h of scalp recordings containing 148 seizures from 19 patients were examined. The averaged sensitivity was 90.9% and selectivity (false-positive errors/h, FPH) was 0.29/h of the Fz-Cz-Pz montage; the other montages yielded lower sensitivities but even better selectivity values. CONCLUSIONS: Taking into account that the method has been performed in a standardized way with fixed parameters for all patients and montages the obtained values for sensitivity are quite high while the selectivity is acceptably low. The parameters can additionally be tuned to patient specific seizures. It is assumed that this may further improve the seizure detection performance. SIGNIFICANCE: The proposed method may enhance the clinical use for the detection of seizures in scalp EEG long-term monitoring during presurgical evaluation. 相似文献
32.
Circulating levels of inflammatory markers and cancer risk in the health aging and body composition cohort. 总被引:8,自引:0,他引:8
Dora Il'yasova Lisa H Colbert Tamara B Harris Anne B Newman Douglas C Bauer Suzanne Satterfield Stephen B Kritchevsky 《Cancer epidemiology, biomarkers & prevention》2005,14(10):2413-2418
BACKGROUND: Chronic inflammation is associated with processes that contribute to the onset or progression of cancer. This study examined the relationships between circulating levels of the inflammatory markers interleukin-6 (IL-6), C-reactive protein (CRP), and tumor necrosis factor-alpha (TNF-alpha) and total as well as site-specific cancer incidence. METHODS: Study subjects (n = 2,438) were older adults (ages 70-79 years) participating in the Health Aging and Body Composition study, who did not report a previous cancer diagnosis (except for nonmelanoma skin cancer) at baseline. Incident cancer events (n = 296) were ascertained during an average follow-up of 5.5 years. Inflammatory markers were measured in stored baseline fasting blood samples. RESULTS: The adjusted hazard ratios (95% confidence intervals) for incident cancer associated with a 1-unit increase on the natural log-scale were 1.13 (0.94-1.37), 1.25 (1.09-1.43), and 1.28 (0.96-1.70) for IL-6, CRP, and TNF-alpha, respectively. Markers were more strongly associated with cancer death: hazard ratios were 1.63 (1.19-2.23) for IL-6, 1.64 (1.20-2.24) for CRP, and 1.82 (1.14-2.92) for TNF-alpha. Although precision was low for site-specific analyses, our results suggest that all three markers were associated with lung cancer, that IL-6 and CRP were associated with colorectal cancer, and that CRP was associated with breast cancer. Prostate cancer was not associated with any of these markers. CONCLUSIONS: These findings suggest that (a) the associations between IL-6, CRP, and TNF-alpha and the risk of cancer may be site specific and (b) increased levels of inflammatory markers are more strongly associated with the risk of cancer death than cancer incidence. 相似文献
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35.
A randomized controlled trial of electromagnetic therapy in the primary care management of venous leg ulceration 总被引:1,自引:1,他引:0
OBJECTIVE: The aim was to establish the potential efficacy, tolerabilityand side-effect profile of electromagnetic therapy as an adjunctto conventional dressings in the treatment of venous leg ulcers. METHOD: A prospective, randomized, double blind controlled clinicaltrial was carried out in a dedicated leg ulcer clinic basedin one urban general practice. Nineteen patients with leg ulcersof confirmed venous aetiology were assessed. The main outcomemeasures were rate and scale of venous leg ulcer healing, changesin patient-reported pain levels, quality of life, degree ofmobility, side effect profile and acceptability to patientsand staff. RESULTS: Sixty-eight per cent of patients attending this dedicated clinicachieved improvements in the size of their ulcer (4, 21%, healedfully) and in reduced pain levels (P < 0.05) during the trial,despite the chronicity of ulcer histories. Patients treatedwith electromagnetic therapy at 800 Hz were found at day 50to have significantly greater healing (P < 0.05) and paincontrol (P < 0.05) than placebo therapy or treatment with600 Hz. All patients reported improved mobility at the end ofthe study. The electromagnetic therapy was well tolerated bypatients, with no differences between groups in reporting adverseevents, and proved acceptable to staff. CONCLUSION: Despite the small numbers in this pilot study, electromagnetictherapy provided significant gains in the healing of venousleg ulcers and reduction in pain. Keywords. Electromagnetic therapy, RCT, leg ulcers, primary care. 相似文献
36.
Bauer Thomas R. Jr; Schwartz Barbara R.; Conrad Liles W.; Ochs Hans D.; Hickstein Dennis D. 《Blood》1998,91(5):1520-1526
37.
Ki-67-determined growth fraction versus standard staging and grading parameters in colorectal carcinoma. A multivariate analysis. 总被引:4,自引:0,他引:4
BACKGROUND. The antibody Ki-67 binds to nuclei in all cell cycle phases except GO and can be used to measure growth fraction. Because proliferative activity has been linked to prognosis in neoplasia, the authors analyzed 100 cases of colorectal carcinoma, each with 3 or more years of follow-up, using Ki-67 immunostaining. METHODS. The Ki-67-positive nuclear area and total nuclear area of carcinoma cells in 20 microscopic fields were measured by computed morphometry. A Ki-67 score (percent positive nuclear area x 100) was calculated. The following characteristics also were recorded for each case: patient age and sex, tumor site and size, modified Dukes' stage, spread beyond bowel wall, lymph node status, tumor grade, histologic type, extramural venous spread, tumor growth pattern, fibrosis, lymphocytic infiltration, and mitotic rate. RESULTS. Ki-67 scores ranged from 1 to 90 (mean, 34.6). Ki-67 scores were higher in Stage A disease (versus Stage B, C, and D disease) but were not associated with survival. Survival curves differed by stage, lymph node metastases, infiltrative growth pattern, lymphocytic infiltration, fibrosis, extramural venous spread, and tumor grade in a univariate analysis. The infiltrative growth pattern (P = 0.04) and lymphocytic infiltration (P = 0.003) were features associated independently with survival after adjusting for modified Dukes' stage. Furthermore, the lack of a significant lymphocytic infiltrate was associated with a death rate 3.4 times greater than that occurring in patients with Stage B disease with a significant infiltrate. CONCLUSIONS. The authors conclude that proliferative activity in colorectal carcinoma as measured by Ki-67 immunostaining was not associated with prognosis. 相似文献
38.
Septic separation of the symphysis pubis 总被引:1,自引:1,他引:0
Summary Symphysial osteomyelitis has been distinguished from osteitis pubis because of the more serious nature of the disease. We report a case in which there was a pelvic separation similar to that seen after trauma or pregnancy. The previously undescribed complications of bladder perforation and pelvic instability are also noted. There was no predisposing cause in this case, in contrast to the 40 previously reported. The causative organism was staphylococcus aureus, but pseudomonas aeruginosa and escherichia coli have also been found in other cases.
Résume L'ostéomyélite de la symphyse pubienne a pu être distinguée de l'ostéite pubienne en raison de sa plus grande gravité. Nous en rapportons un cas dans lequel existait une disjonction symphysaire semblable à celles que l'on observe après traumatisme ou grossesse. On a également noté des complications jamais décrites, à savoir une perforation vésicale et une instabilité pelvienne. Il n'y avait pas de cause prédisposante dans ce cas, contrairement aux 40 observations précédemment rapportées dans la littérature. La bactérie causale était un staphylocoque doré, mais le pyocyanique et le colibacille ont également été retrouvés dans d'autres cas.相似文献
39.
40.
Pharmacokinetics of tacrolimus (FK 506) in children and adolescents with renal transplants 总被引:3,自引:0,他引:3
Filler G; Grygas R; Mai I; Stolpe H; Greiner C; Bauer S; Ehrich J 《Nephrology, dialysis, transplantation》1997,12(8):1668-1671
Background: Only few data exist on pharmacokinetics of
tacrolimus in children. Patients: In 1995 and 1996, 14
children (mean age 13 years, range 5-23 years) received tacrolimus after
renal transplantation; 10 of these after biopsy-proven steroid-resistant
rejection (2 with vascular rejection), two for cyclosporin A (CsA)-induced
severe nephrotoxicity, one for untreatable gingival hyperplasia on CsA, and
one child was treated primarily after transplantation because of severe
liver involvement in nephronophthisis. Pharmacokinetic investigations were
performed after establishing a stable maintenance dose with trough levels
in the desired window of 5-12 ng/ml. Results: Mean
follow-up time was 6 months (range 3-25 months). Eleven patients were still
on tacrolimus. Two were discontinued because of severe aggravation of
chronic persistent hepatitis C (one of them also developed diabetes
mellitus),and one patient was subsequently switched to conventional
immunosuppression because of tacrolimus-associated nephrotoxicity. All
tacrolimus levels were measured by a modified assay (MEIA, Tacrolimus,
Abbott) with improved sensitivity. At the time of switch, median serum
creatinine was 234±82 7mgr;mol;l and 6 months after switch
201±99 &mgr;mol/l. All grafts are still functioning. Mean
FK-506 dose was 0.16 mg/kg body weight/day (range 0.036-0.30 mg/kg). Mean
trough level was 7.1±2.6 ng/ml in the morning and
6.5±2.0 ng/ml in the evening. Median time of maximum
concentration (tmax) was 120 min after application, and the mean maximum
concentration (Cmax) was 15.2±6.7 ng/ml. Mean area under the
curve (AUC) was 104±33 ng * h/ml, with a range from 65 to 169 ng
* h/ml. No patient had unsatisfactorily low trough levels during the study.
There was only a weak but significant (P<0.05) correlation between
dose per kg body weight and AUC and, as expected, an excellent correlation
(r2=0.73, P<0.001) between AUC and trough
level. Conclusion: Because of interindividual
variation between patients, therapeutic drug monitoring of tacrolimus is
mandatory. In this study, a daily dose of 0.15 mg/kg was sufficient in most
patients. We recommend the performance of at least one pharmacokinetic
study after establishing stable FK 506 trough levels to ascertain a safe
profile. 相似文献