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81.
The utilization of glucose, palmitate, and oleate for the synthesis of lung lipids was studied in isolated rat lungs. Lungs were ventilated with 5% CO2 in air and perfused for 100 min with a Krebs-Ringer bicarbonate buffer (pH 7.4), containing 3% fatty acid-free albumin and either 5.6 mM [U-14C]glucose or 0.25 mM [1-14C]palmitate, or 0.25 mM [1-14C]-oleate. At the end of 100 min of perfusion with these precursors, between 73 and 85% of total lipid 14C was recovered as phospholipid. Glucose carbon was mainly incorporated into triglyceride fatty acids (TG-FA) and phosphatidylcholine fatty acids (PC-FA) of 16- and 18-carbon chain length. After perfusion with [14C]palmitate and [14C]oleate, only 65 and 20% of 14C was recovered as PC 16-carbon and 18-carbon FA, respectively. The remaining 14C was mainly recovered as FA shorter than the 14C precursors. Schmidt degradation analysis of lipid FA demonstrated considerable labeling of alkyl carbons on perfusion with the carboxyl-labeled precursors, indicating that FA degradation products were used for synthesis of lipid FA. This process was enhanced on addition of glucose to the perfusate.  相似文献   
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BACKGROUND: Enterovirus (EV) infections commonly cause fever in infants younger than 90 days of age. The polymerase chain reaction (PCR) has improved our ability to diagnose EV infections. OBJECTIVE: To evaluate the utility of blood and cerebrospinal fluid (CSF) specimens for the diagnosis of EV infections by PCR and to describe a large cohort of EV-infected infants. DESIGN/METHODS: Febrile infants younger than 90 days of age evaluated for sepsis at Primary Children's Medical Center in Salt Lake City, UT, were enrolled in a prospective study designed to identify viral infections from December 1996 to June 2002. All patients had bacterial cultures of blood, urine and CSF. Testing for EV was performed by PCR and/or viral cultures. Patients who were positive for EV were identified for this study. RESULTS: Of 1779 febrile infants enrolled, 1061 had EV testing and 214 (20%) were EV-positive. EV infections were diagnosed by PCR of blood, CSF or both in 93% of infants. PCR testing was positive in blood in 57%, and blood was the only positive specimen for 22% of EV infected infants. PCR of CSF was positive in 74%. The mean age of infants with EV infection was 33 days, with 18% younger than 14 days and 5% younger than 7 days. Fifty percent of EV-positive infants had CSF pleocytosis. Of EV PCR-positive infants, 91% were admitted, and 2% required intensive care. Possible serious EV disease was diagnosed in <1%, and there were no deaths. Twelve infants (5.6%) had concomitant urinary tract infection, and 3 (1%) had bacteremia. CONCLUSIONS: EV infections are common in febrile infants younger than 90 days. Blood and CSF are equally likely to yield positive results by PCR, but the combination of both specimens improved the diagnostic yield.  相似文献   
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AIMS: To compare the subjective acceptability of CT colonography in comparison with barium enema in older symptomatic patients, and to ascertain preferences for future colonic investigation. MATERIALS AND METHODS: The study population comprised 78 persons aged 60 years or over with symptoms suggestive of colorectal neoplasia, who underwent CT colonography followed the same day by barium enema. A 25-point questionnaire was administered after each procedure and an additional follow-up questionnaire a week later. Responses were compared using Wilcoxon matched pairs testing, Mann-Whitney test statistics and binomial exact testing. RESULTS: Participants suffered less physical discomfort during CT colonography (p = 0.03) and overall satisfaction was greater compared with barium enema (p = 0.03). On follow-up, respondents reported significantly better tolerance of CT colonography (p = 0.002), and were less prepared to undergo barium enema again (p < 0.001). Of 52 subjects expressing an opinion, all preferred CT to barium enema. CONCLUSION: Patient satisfaction was higher with CT colonography than barium enema. CT colonography caused significantly less physical discomfort and was overwhelmingly preferred by patients.  相似文献   
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Research College of Nursing and the Rockhurst University Helzberg School of Management Health Care Initiative collaborated to offer the Executive Nurse Practice: Health Care Leadership track to Research College of Nursing graduate students. This effort was not only cost effective, but also offered expert faculty in both the fields of nursing and business. The curriculum is an integration of both fields and faculties from both institutions as they communicate and collaborate each semester to successfully coordinate the track.  相似文献   
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1. Large-scale mutagenic screens of the zebrafish genome have identified a number of different classes of mutations that disrupt skeletal muscle formation. Of particular interest and relevance to human health is a class of recessive lethal mutations in which muscle differentiation occurs normally, but is followed by tissue-specific degeneration reminiscent of human muscular dystrophies. 2. We have shown that one member of this class of mutations, sapje (sap), results from mutations within the zebrafish orthologue of the human Duchenne muscular dystrophy (DMD) gene. Mutations in this locus cause Duchenne or Becker muscular dystrophies in human patients and are thought to result in a dystrophic pathology by disrupting the link between the actin cytoskeleton and the extracellular matrix in skeletal muscle cells. 3. We have found that the progressive muscle degeneration phenotype of sapje-mutant zebrafish embryos is caused by the failure of somitic muscle attachments at the embryonic myotendinous junction (MTJ). 4. Although a role for dystrophin at the MTJ has been postulated previously and MTJ structural abnormalities have been identified in the dystrophin-deficient mdx mouse model, in vivo evidence of pathology based on muscle attachment failure is thus far lacking. Therefore, the sapjre mutation may provide a model for a novel pathological mechanism of Duchenne muscular dystrophy and other muscle diseases. In the present review, we discuss this finding in light of previously postulated models of dystrophin function.  相似文献   
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