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Omega-3 fatty acids are essential fatty acids that must be consumed in the diet. Adequate consumption of omega-3 fatty acids is vitally important during pregnancy as they are critical building blocks of fetal brain and retina. Omega-3 fatty acids may also play a role in determining the length of gestation and in preventing perinatal depression. The most biologically active forms of omega-3 fatty acids are docosahexaenoic acid and eicosapentaenoic acid, which are primarily derived from marine sources such as seafood and algae. Recent surveys, however, indicate that pregnant women in the United States and in other countries eat little fish and therefore do not consume enough omega-3 fatty acids, primarily due to concern about the adverse effects of mercury and other contaminants on the developing fetus. This review discusses the benefits of omega-3 fatty acid consumption during pregnancy and provides guidelines for obstetricians advising patients.  相似文献   
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The bone-anchored hearing aid (BAHA) is an effective means of intervention, its use being well documented in persons with chronic conductive pathology and congenital aural anomalies. This article describes the standard guidelines (both auditory and extraauditory aspects) for patient selection and expands the criteria to include bilateral BAHA implantation, unilateral conductive hearing loss, and unilateral profound sensorineural hearing loss. The BAHA's development, design features, and patient outcomes are also reviewed. Suggestions are presented for fitting, counseling, and following BAHA users.  相似文献   
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We investigated the frequency of p53 mutations in 47 pediatric brain tumors of various histologic subtypes that were collected over a period of 5 years. The specimens included 15 primitive neuroectodermal tumors (PNETs), 17 low grade astrocytomas, one anaplastic astrocytoma, three glioblastomas (GBMs), one mixed glial tumor, eight ependymomas, one choroid plexus carcinoma, and one gangliocytoma/ganglioneuroma. Mutations were identified by single strand conformation polymorphism analysis of exons 4–8 and verified by sequencing. Mutations were present in 2 of 3 cases of GBM, but not in 17 low grade astrocytomas (P = 0.02, Fisher's exact test). One GBM demonstrated a germline GGC to AGC transition (gly to ser) at codon 245 with loss of the wild-type allele. A second GBM contained a CGG to TGG transition (arg to trp) at codon 248, also with loss of the wildtype allele, but normal tissue was not available for comparison. In addition, one of 15 PNETs retained heterozygosity but demonstrated a somatic CGT to TGT transition (arg to cys) at codon 273. p53 mutations were absent in other histologic subtypes and in two cases with multiple primary cancers. These data are consistent with earlier findings that p53 mutations are rare in PNETs, which are primarily pediatric tumors. In contrast to adult gliomas, p53 mutations in pediatric gliomas appear restricted to the GBMs. The lack of p53 mutations in pediatric low grade astrocytomas suggests not only histological differences, but also a different molecular pathogenesis in adult and pediatric patients. © 1995 Wiley-Liss, Inc.  相似文献   
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Role of the bispectral index in sedation monitoring in the ICU   总被引:2,自引:0,他引:2  
OBJECTIVE: To review and critique evidence for the use of the bispectral index (BIS) in intensive care unit (ICU) patients. DATA SOURCES: A computer search of English-language articles in MEDLINE (1966-July 2005), International Pharmaceutical Abstracts (1971-July 2005), and Scientific Citation Index Expanded (1980-July 2005) was conducted. A manual search of abstracts was also performed using the key search terms BIS, sedation, and critical care. STUDY SELECTION AND DATA EXTRACTION: Case series, letters, editorials, and clinical studies that evaluated BIS in ICU patients were considered for inclusion. DATA SYNTHESIS: Nineteen studies comparing the BIS with sedation scales were evaluated, revealing that the BIS trends lower with increasing sedation. The BIS appeared to correlate better when sedation scores were grouped rather than individual values. However, correlations between BIS and subjective scales were low in most studies (r(2) 0.21-0.93). Additionally, there was poor correlation between drug dosage and the BIS. Randomized, controlled trials demonstrating improved outcomes with BIS monitoring have not been reported. CONCLUSIONS: Interpreting literature on the usefulness of the BIS in the ICU is difficult for reasons that include heterogeneous populations, different methods of collecting BIS data, and use of different versions of BIS software and hardware. Outcomes data are lacking. The 2002 Society of Critical Care Medicine Sedation Guidelines recommendation that more data are needed before the BIS should be used routinely in the ICU remains unchanged. We recommend that further studies be conducted to determine the optimal method of obtaining BIS data and evaluate the impact of the BIS on relevant patient outcomes.  相似文献   
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OBJECTIVES/HYPOTHESIS: Electromagnetic therapy has been used with reported success in multiple clinical settings, including the treatment of seizure disorders, brain edema, migraine headaches, revascularization of burn wounds, and diabetic ulcers. The purpose of the study was to investigate the effect of pulsed high-frequency electromagnetic therapy on chronic tinnitus. STUDY DESIGN: A randomized, prospective, double-blind, placebo-controlled pilot study was conducted to evaluate the effectiveness of high-frequency pulsed electromagnetic energy using the Diapulse device in the treatment of chronic tinnitus. Thirty-seven adult patients with chronic tinnitus of at least 6 months' duration were recruited and randomly assigned to either a treatment or a placebo group. METHODS: Patients received 30-minute treatments with the Diapulse device three times a week for 1 month. The unit was set to deliver electromagnetic energy at a frequency of 27.12 MHz at a repetition rate of 600 pulses per second. All subjects had pretreatment and post-treatment audiological testing, including tinnitus frequency and intensity matching. They responded to a tinnitus rating questionnaire and the Tinnitus Handicap Inventory before and after treatment. RESULTS: There was no significant change in the pretreatment and post-treatment audiometric thresholds in either group. There were no significant differences between the pretreatment and post-treatment Tinnitus Handicap Inventory scores or the tinnitus rating scores in either subject group (Student t test). No diagnosis-specific differences were identified. CONCLUSION: High-frequency pulsed electromagnetic energy (Diapulse) at the settings used in the study showed no role in the therapy of patients with chronic tinnitus.  相似文献   
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This study explored how mothers grouped into clusters according to multiple psychographic food decision influencers and how the clusters differed in nutrient intake and nutrient content of their household food supply. Mothers (n = 201) completed a survey assessing basic demographic characteristics, food shopping and meal preparation activities, self and spouse employment, exposure to formal food or nutrition education, education level and occupation, weight status, nutrition and food preparation knowledge and skill, family member health and nutrition status, food decision influencer constructs, and dietary intake. In addition, an in-home inventory of 100 participants' household food supplies was conducted. Four distinct clusters presented when 26 psychographic food choice influencers were evaluated. These clusters appear to be valid and robust classifications of mothers in that they discriminated well on the psychographic variables used to construct the clusters as well as numerous other variables not used in the cluster analysis. In addition, the clusters appear to transcend demographic variables that often segment audiences (eg, race, mother's age, socioeconomic status), thereby adding a new dimension to the way in which this audience can be characterized. Furthermore, psychographically defined clusters predicted dietary quality. This study demonstrates that mothers are not a homogenous group and need to have their unique characteristics taken into consideration when designing strategies to promote health. These results can help health practitioners better understand factors affecting food decisions and tailor interventions to better meet the needs of mothers.  相似文献   
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