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OBJECTIVE: The objective of this study was to evaluate the efficiency of the detection of the S-T segment in the fetal PQRST complex that is recorded in the antepartum period with the use of a newly developed noninvasive 151-channel magnetic sensor array. STUDY DESIGN: One hundred two fetal magnetocardiographic recordings were performed on normal fetuses with gestational ages that ranged from 27.5 to 39.5 weeks. After the removal of the interfering maternal heart signals, the fetal heart data were inspected to detect the presence of P, QRS, and T segments. RESULTS: The QRS complex was detectable in 100%, the P wave was detectable in 95.1%, and the T wave was detectable in 87.3% of the recordings. CONCLUSION: Fetal magnetocardiography was recorded successfully, the QRS complex was observed in all subjects, and the T detection rate increased, with the gestational age reaching a peak of 97%. Further study of the S-T segment through the antepartum period could lead to advances in the detection of fetal jeopardy before labor.  相似文献   
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Enteral glutamine supplementation and morbidity in low birth weight infants   总被引:10,自引:0,他引:10  
OBJECTIVE: To determine if glutamine-supplemented enteral nutrition decreased the incidence of nosocomial sepsis in neonates. METHODS: In a multicenter (n = 20) clinical trial, we randomly allocated infants (n = 649) with birth weight between 500 and 1250 g, who were <7 days of age, and had no major anomalies to receive enteral glutamine supplementation (0.3 g/kg/day) or sterile water (placebo) for the first 28 days. The primary outcome variable was the number of infants who had blood culture-proven nosocomial sepsis between 7 days' and 36 weeks' postmenstrual age. RESULTS: Infants were assigned to placebo (n = 335) or to glutamine supplementation (n = 314). Neonates assigned to glutamine were similar to those assigned placebo for demographic characteristics and nutritional support during the first week. There was no difference in the occurrence of culture-proven nosocomial sepsis (33.7% vs 30.9%) or suspected sepsis (51.6% vs 47.1%) between the placebo and glutamine groups; however, neonates treated with glutamine less often had gastrointestinal dysfunction (7.5% vs 2.5%, P <.01) and severe neurologic sequelae (15.1% vs 10.4%, P =.08). CONCLUSIONS: At a dose of 0.3 g/kg/day, enteral glutamine does not appear to reduce nosocomial sepsis in premature neonates.  相似文献   
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Chlamydophila felis and feline herpesvirus (FHV) are pathogens commonly associated with feline respiratory and ocular disease. A real-time multiplex PCR assay was developed to allow detection of these organisms, together with feline 28S ribosomal DNA, in a single tube. Of 538 ocular swab samples tested, 123 were positive for FHV, 97 were positive for C. felis, and 16 were positive for both pathogens.  相似文献   
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Reporting cutaneous melanoma to cancer registries in the United States   总被引:1,自引:0,他引:1  
BACKGROUND: Central cancer registries provide data to monitor incidence rates of cutaneous melanoma. OBJECTIVE: The aim of this study was to assess the completeness of melanoma reporting in the United States. METHODS: Data provided by central cancer registries were used to calculate age-adjusted, average annual incidence rates and were compared by time period (1992-1994, 1995-1997), stage, and program (Surveillance Epidemiology and End Results [SEER] and National Program of Cancer Registries [NPCR]). Completeness was measured with incidence/mortality ratio. RESULTS: Incidence rates among whites for 1995-1997 from SEER registries ranged from 11.8 to 33.9 per 100,000 population; 18 of 40 NPCR registries were within this range. For 1992-1994, 8 of 30 NPCR registries were within the range of SEER incidence rates. NPCR registry incidence rates were generally higher for 1995-1997 than 1992-1994. The percentage of cases of localized melanoma did not increase substantially in most SEER registries over the study period, but some NPCR registries had substantial increases. Among NPCR registries that had incidence rates comparable with those of SEER in 1995-1997, the incidence/mortality ratios were generally lower among NPCR registries than SEER registries. CONCLUSION: Although melanoma incidence rates are generally increasing, part of the increases in incidence rates reported by NPCR registries over the study time period are likely due to increased case ascertainment and reporting.  相似文献   
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Baxendale S  Thompson P  Duncan J  Richardson M 《Neurology》2003,60(2):354-5; author reply 354-5
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