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71.
The dynamic studies of P300 component of the acoustic evoked potential were conducted in 12 patients in posttraumatic state of the autonomic system. The amplitude and time parameters of P300 were analyzed, its spatial distribution over the cortex, and features of generation. The obtained results were compared with the normative data. Significant changes in P300 in comparison with the normal characteristics were revealed in patients with the absence of conscious mental activity. These changes were maximally expressed when the state of patients was irreversible. In case of patients' outcome from the studied state the amplitude-temporal and topographic response characteristics tended to normalization but did not reach it completely. The obtained results allow us to consider the P300 component as one of the most informative indices in consciousness recovery after severe brain injury.  相似文献   
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Hepatocyte cultures have been used in pharmacotoxicological studies, and sulfotransferases (ST) are important drug-metabolizing enzymes in liver. The expression of sulfotransferases in hepatocyte cultures has not been examined systematically. In the present study, the mRNA levels of different sulfotransferases in male and female rat hepatocytes were examined by northern-blot analyses. Various culture conditions such as different matrices (collagen, matrigel, collagen sandwich, or co-culture with epithelial cells), medium (Way-mouth's MB 752/1 and Modified Chee's Medium) and glucocorticoid supplementation (dexamethasone, 0.1 microM) were compared. Phenol ST (ST1A1) mRNA levels decreased to about 50% of initial mRNA levels within 10 hr of culture. At 96 hr, ST1A1 mRNA levels were approximately 20% of initial values when cultured on collagen, matrigel or co-culture. The two media did not differ in ability to maintain ST1A1 mRNA levels in the absence of dexamethasone (DEX); however, DEX addition to either medium resulted in ST1A1 mRNA levels greater than 100% of the initial mRNA levels at 96 hr, with the greatest increase observed using the matrigel substratum and Chee's medium. In the absence of DEX, the mRNA levels of N-hydroxy-2-acetylaminoflurene sulfortransferase (ST1C1), estrogen sulfotransferase (ST1E2) and hydroxysteroid sulfotransferase (ST-20/21, ST-40/41, ST-60) fell to approximately 20% of their initial levels within 24 hr, and to less than 5% at 96 hr. The loss of expression of these sulfotransferases was observed with all culture conditions. Addition of DEX to the media resulted in ST-40/41 and ST-60 mRNA expression at 20 and 35% of their initial values, respectively, in cultures maintained on matrigel and Chee's medium at 96 hr. These data suggest that sulfotransferases lose their constitutive expression in hepatocyte culture, but retain their inducibility.  相似文献   
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EL Petsonk  RM Castellan  GR Wagner 《Canadian Metallurgical Quarterly》1995,332(20):1380; author reply 1380-1380; author reply 1381
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76.
This study examines whether, while controlling for local economic conditions, job design and other organizational factors affect facility aide turnover rates in a sample of 250 nursing homes from 10 states. Facility characteristics were largely based on administrator and director of nursing interviews conducted in 1993 as part of the Health Care Financing Administration's evaluation of the Resident Assessment Instrument (RAI) implementation. Aide turnover was significantly reduced by involvement in interdisciplinary care plan meetings. Turnover rates were higher in for-profit homes. Aide involvement in assessments, aide training and workload, case mix severity, payor source mix, and facility size were not significantly related to aide turnover.  相似文献   
77.
We model interference effects in fiber optic methane sensors and predict the influence on the sensitivity. System sensitivity in terms of minimum detectable methane concentration is expressed as a function of birefringence, spectral transmission characteristics and polarization dependent loss of the fiber system, and the polarization and coherence characteristics of the light source. The sensitivity is calculated for various system arrangements and compared with existing experimental data. The model predicts that the interference effects may be minimized by using a depolarized broadband source (say, 30-50 nm) with a Gaussian spectral lineshape, together with a birefringence balanced sensor configuration  相似文献   
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DJ Trigg  EL Applebaum 《Canadian Metallurgical Quarterly》1998,19(5):679-84; discussion 684-6
OBJECTIVE: This study aimed to clarify the indications for elective surgical repair of unilateral aural atresia in children and to review the rates of successful repair in the literature. DATA SOURCES: A search of the published English language literature, 1966-1997, was conducted using the key words aural atresia. STUDY SELECTION: Articles were selected on the basis of their inclusion of the authors' indications for surgical repair of aural atresia or the inclusion of surgical series that showed outcomes. DATA EXTRACTION: Articles reviewed in the review had to either provide specific guidelines for surgical repair of unilateral aural atresia or provide postoperative pure-tone averages, air-bone gaps, or speech reception thresholds. DATA SYNTHESIS: The authors compiled the relevant data into summary tables and extracted conclusions from these data. CONCLUSIONS: Elective surgical repair of unilateral aural atresia should only be attempted in children who meet specific anatomic criteria that predict that they are the most likely to benefit from the results of surgery. Otherwise, repair should be delayed until the age at which the patient can make an informed decision, knowing the risks, benefits, and consequences of this difficult surgery. Parents and surgeons must have a realistic expectation of the surgical results and the practiced benefit to be expected with a normal, contralateral ear.  相似文献   
80.
Refusal to eat by the elderly, and subsequent malnutrition, occurs in both institutional and community settings. Causes include physiologic changes associated with aging, mental disorders such as dementia and depression, and medical, social, and environmental factors. Treatment approaches call for management of these causes while considering the roles that medicine, ethics, and culture play in the process.  相似文献   
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