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101.
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While treatment for the neonate continues to be challenging, current technical advances offer more options. Before the 1980s chronic dialysis was technically so difficult for neonates and infants that most considered it impossible; in the 1990s renal replacement therapy is a viable choice. The purpose of this article is neither to advocate active intervention nor passive supportive care, but to help the reader consider questions frequently faced when deciding what to do for a neonate with end-stage renal disease (ESRD). Today ethical issues are tied closely to health care reform, so this bioethical dilemma has only begun. As health care reform addresses benefits of care, the bioethical dilemmas raised by neonates with ESRD will need to carefully considered.  相似文献   
103.
Hypertension     
Chemotherapeutic agents administered to the mother during pregnancy may severely jeopardize the fetus. We describe a newborn girl who had been exposed to idarubicin and cytosine-arabinoside during the second and third trimesters of pregnancy due to treatment of newly diagnosed acute myeloid leukemia in the mother. The child had no structural congenital abnormalities. Adverse effects observed were prematurity, growth retardation, mildly disturbed transaminases and erythroblastosis, all of which were self-limiting with no permanent sequelae.  相似文献   
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Acute nonfatal erysipelas was diagnosed in 4 sows in a 1,000-sow commercial farrow-to-finish operation in Indiana. Sows were pyrexic, lethargic, lame, and had multiple, 1.3- to 7.6-cm, erythematous rhomboid skin lesions. Outbreak was attributed to failure to properly vaccinate pigs. Further morbidity and mortality were prevented by treatment of clinically affected sows and all pigs in close proximity with procaine penicillin G daily for 3 consecutive days and vaccination of all pigs with questionable vaccination status, using bacterin of killed Erysipelothrix rhusiopathiae. Periodic review of herd management protocols is important to ensure that recommended vaccination schedules are being followed and animals are receiving quality vaccinations. Human error can contribute to many production problems and should be included on the differential diagnoses list.  相似文献   
106.
Sustained iontophoresis of NMDA potentiated visual responses for minutes after the application in 16 of 38 cells (42%), peaking 3 min after the end of the application and declining to control levels within 12 min. Potentiation was also seen after application of ACPD (36%, n = 14) and AMPA (29%, n = 14), but not after application of ACh (n = 20). ACh also excites dLGN cells, but does not interact with amino acid receptors, and ACh receptors are not directly involved in the transmission of visual information. We suggest that this modulation is a form of visually induced potentiation which permits dynamic modification of the strength of visual information to be relayed to the cortex depending upon the history of previous activity levels.  相似文献   
107.
ADP-ribosylation factor 5 (ARF5) is a member of the ARF gene family. The ARF proteins stimulate the in vitro ADP-ribosyltransferase activity of cholera toxin and appear to play a role in vesicular trafficking in vivo. We have mapped ARF5, one of the six known mammalian ARF genes, to a well-defined yeast artificial chromosome contig on human chromosome 7q31.3. In addition, we have isolated and sequenced an approximately 3.2-kb genomic segment that contains the entire ARF5 coding region, revealing the complete intron-exon structure of the gene. With six coding exons and five introns, the genomic structure of ARF5 is unique among the mammalian ARF genes and provides insight about the evolutionary history of this ancient gene family.  相似文献   
108.
Swan-Ganz catheter-induced pulmonary artery (PA) rupture is rare, with an incidence of 0.016 to 0.2 per cent, but it remains the most dreaded complication in the placement of these catheters with a mortality above 50 per cent. We report two cases of PA rupture after catheter placement. Both patients were managed nonoperatively and without any invasive procedure. They both stopped bleeding after the initial episode and were discharged a few days later. We believe that in the absence of high-risk factors, such as pulmonary hypertension and systemic anticoagulation, PA rupture from a Swan-Ganz catheter can be successfully treated by withdrawal of the catheter and supportive care.  相似文献   
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Control of oxidative metabolism was studied using 13C NMR spectroscopy to detect rate-limiting steps in 13C labeling of glutamate. 13C NMR spectra were acquired every 1 or 2 min from isolated rabbit hearts perfused with either 2.5 mM [2-13C]acetate or 2.5 mM [2-13C]butyrate with or without KCl arrest. Tricarboxylic acid cycle flux (VTCA) and the exchange rate between alpha-ketoglutarate and glutamate (F1) were determined by least-square fitting of a kinetic model to NMR data. Rates were compared to measured kinetics of the cardiac glutamate-oxaloacetate transaminase (GOT). Despite similar oxygen use, hearts oxidizing butyrate instead of acetate showed delayed incorporation of 13C label into glutamate and lower VTCA, because of the influence of beta-oxidation: butyrate = 7.1 +/- 0.2 mumol/min/g dry wt; acetate = 10.1 +/- 0.2; butyrate + KCl = 1.8 +/- 0.1; acetate + KCl = 3.1 +/- 0.1 (mean +/- SD). F1 ranged from a low of 4.4 +/- 1.0 mumol/min/g (butyrate + KCl) to 9.3 +/- 0.6 (acetate), at least 20-fold slower than GOT flux, and proved to be rate limiting for isotope turnover in the glutamate pool. Therefore, dynamic 13C NMR observations were sensitive not only to TCA cycle flux but also to the interconversion between TCA cycle intermediates and glutamate.  相似文献   
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