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171.
MJ Melero DE Mattar FM Stengel AJ Politi LB Idiarte MC Bacque 《Canadian Metallurgical Quarterly》1993,53(3):232-234
In rheumatoid synovium interleukin 6 (IL-6) is the most abundantly expressed cytokine. Increased serum levels have been previously reported in patients with rheumatoid arthritis (RA). In this study serum IL-6 levels were measured in a well defined cohort using a bioassay (B9 cells) and levels were correlated with conventional clinical and laboratory indices of disease activity. Levels were significantly higher in serum from patients with RA (median 55 IU/ml; interquartile range 28-139) compared with serum from disease (median 7 IU/ml; 1-23) and normal controls (median 10 IU/ml; 7-12). No difference was observed between men and women. Levels did not correlate with disease duration. Significant associations were observed between IL-6 and C reactive protein and between the Ritchie articular index and duration of morning stiffness. No other correlations were observed. The value of these findings in the monitoring of RA and as an indicator of response to second line treatment needs to be established. 相似文献
172.
LB Lehman 《Canadian Metallurgical Quarterly》1996,276(24):1951; author reply 1951-1951; author reply 1952
173.
LL Gunderson CG Willett LB Harrison IA Petersen MG Haddock 《Canadian Metallurgical Quarterly》1997,24(6):715-731
Intraoperative radiation therapy (IORT) in its broadest sense refers to the delivery of irradiation at the time of an operation. This article will discusses the rationale for and results of both intraoperative electron radiation therapy and intraoperative high dose rate brachytherapy when used in conjunction with surgical exploration and resection and external beam radiation therapy and chemotherapy. Both IORT methods evolved with similar philosophies as an attempt to achieve higher effective doses of irradiation while dose limiting structures are surgically displaced. 相似文献
174.
Gantz, et al, reported two patients with extensive cochlear ossification in which cochlear implantation was done with a Nucleus 22-Channel Cochlear Implant after extensive cochlear drill-out. One of the patients did well with 20 functioning electrode pairs. We report an additional three patients with extensive cochlear ossification who received Nucleus 22-Channel Cochlear Implants. All three patients had extensive cochlear drill-out as described by Gantz, et al. All three patients have use of all 21 electrode pairs with amperages typical of conventional implantation in two of the three and slightly increased levels in the third. Extensive bilateral cochlear ossification does not seem to be an absolute contraindication for multi-channel cochlear implantation. 相似文献
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177.
The purpose of the work reported here was to investigate the application of neural control to a common industrial process. The chosen problem was the control of a batch distillation. In the first phase towards deployment, a complex software simulation of the process was controlled. Initially, the plant was modelled with a neural emulator. The neural emulator was used to train a neural controller using the back propagation through time algorithm. A high accuracy was achieved with the emulator after a large number of training epochs. The controller converged more rapidly, but its performance varied more widely over its operating range. However, the controlled system was relatively robust to changes in ambient conditions. 相似文献
178.
179.
LB Goldstein AJ Bonito DB Matchar PW Duncan GH DeFriese EZ Oddone JE Paul DR Akin GP Samsa 《Canadian Metallurgical Quarterly》1995,26(9):1607-1615
BACKGROUND AND PURPOSE: Stroke is largely a preventable disease. However, there are little data available concerning the use of stroke prevention diagnostic and treatment modalities by practicing physicians. These data are critical for the rational allocation of resources and targeting of educational efforts. The purposes of this national survey were to gather information about physicians' stroke prevention practice patterns and their attitudes and beliefs regarding secondary and tertiary stroke prevention strategies. METHODS: We conducted a national survey of stroke prevention practices among a stratified random sample of 2000 physicians drawn from the American Medical Association's Physician Masterfile. The survey focused on the availability of services and the use of diagnostic and preventive strategies for patients at elevated risk of stroke. RESULTS: Sixty-seven percent (n = 1006) of eligible physicians completed the survey. Diagnostic studies considered readily available by at least 90% of physicians included carotid ultrasonography, transthoracic echocardiography, Holter monitoring, and brain CT and MRI scans. MR angiography was perceived as being readily available by 68% and transesophageal echocardiography by 74% of respondents. Twelve percent of physicians reported cerebral arteriography and 10% reported carotid endarterectomy as not being readily available. Multiple logistic regression analyses showed that the availability of services varied with physician specialty (noninternist primary care, internal medicine, neurology, surgery), practice setting (nonmetropolitan versus small metropolitan or large metropolitan areas), and for carotid endarterectomy, region of the country (South, Central, Northeast, and West). The odds of carotid endarterectomy being reported as readily available were approximately 2.5 to 3.5 times greater for physicians practicing in the central, northeastern, and western regions compared with those practicing in the South, independent of practice setting and specialty. With regard to stroke prevention practices, 61% of physicians reported prescribing 325 mg of aspirin for stroke prevention, while 33% recommend less than 325 mg and 4% use doses of 650 mg or more. Seventy-one percent of physicians using warfarin reported monitoring anticoagulation with international normalized ratios, and 78% reported monitoring anticoagulated patients at least once a month. Fewer than 20% of physicians reported knowing the perioperative carotid endarterectomy complication rates at the hospital where they perform the operation themselves or refer patients to have the procedure done. CONCLUSIONS: Although all routine and most specialized services for secondary and tertiary stroke prevention are readily available to most physicians, variation in availability exists. The use of international normalized ratios for monitoring warfarin therapy has not yet become universal. Physician knowledge of carotid endarterectomy complication rates is generally lacking. Depending on their causes, these problems may be addressed through targeted physician education efforts and systematic changes in the way in which services are provided. 相似文献
180.
OBJECTIVES: A total of 97 apparently healthy subjects were studied in order to establish the influence of smoking habits in studies on neurocardiovascular control and the QTc interval duration. MATERIAL AND METHODS: The study group consisted of 37 smokers and 60 non-smokers as the control. A 12-lead electrocardiogram was performed on all subjects to determine the duration of the QTc interval. Other aspects studied include heart rate variability at rest during 150 cardiac cycles using time domain: coefficient of variation and root mean squared successive difference; and frequency domain: low frequency band (0.04-0.15 Hz) and high frequency band (0.15-0.50 Hz), to determine total energy logarithm and maximum energy frequency. Additionally, conventional cardiovascular autonomic function tests, such as orthostasis, Valsalva maneuver and deep breathing were performed. RESULTS: No significant differences were observed in the duration of the QTc interval nor in time and frequency domain parameters, except in the maximum frequency in the high frequency band, which appeared significantly lower (p < 0.05) in smokers when compared to non-smokers (0.28 +1- 0.1 vs 0.33 +/- 0.1 Hz). No modifications were noted in the cardiovascular autonomic function tests applied to smokers and non-smokers, and the QTc interval was not linked to the rest of the variables studied. CONCLUSIONS: To conclude, smoking habits do not seem to have a significant influence in studies addressed to determine the impact of the autonomic nervous systems on cardiovascular control. 相似文献