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1.
BACKGROUND: The 1997 National Asthma Education and Prevention Program (NAEPP) recommends a severity classification scheme to optimize the use of anti-inflammatory therapy for persistent asthma. Physician documentation of asthma severity is often used as a quality assurance measure. OBJECTIVE: To test the hypothesis that physician documentation of asthma severity is associated with appropriate use of anti-inflammatory therapy. DESIGN/METHODS: Setting: inner-city academic health center. First, we reviewed a consecutive sample of charts of scheduled pediatric patients. Then, we administered a structured parent survey regarding the child's asthma symptoms and current asthma therapy. We used NAEPP guidelines to classify patients' severity of asthma. The main outcome measure was appropriate use of anti-inflammatory therapy. Appropriate therapy was defined as: (1) mild persistent asthmatics using anti-inflammatory therapy, and (2) moderate-severe persistent asthmatics using inhaled steroids. Chart classification of asthma severity was compared with the NAEPP-applied classification. RESULTS: Of 784 charts, 214 (27%) were asthmatic. Of these, 176 (82%) were surveyed. The mean age was 7.4 years; 61% were males. Severity classification was documented in 77% of charts. Chart documentation differed significantly from survey classification for the same patients: (mild intermittent 54% vs. 40%, mild persistent 21% vs. 14%, moderate persistent 24% vs. 36%, severe persistent 1% vs. 10%; all p < .001). Correctly classified patients were more likely to be on appropriate therapy. CONCLUSIONS: Physicians underestimated the severity classification of asthmatic patients. Incorrect classification was associated with inappropriate asthma therapy. These findings have implications for the institution of asthma quality improvement programs.  相似文献   
2.
The influence of experimentally induced hepatic dysfunction on the pharmacokinetics of Cyclosporine A (CsA) was determined in dogs. The pharmacokinetics of oral (PO) and intravenous (IV) CsA were studied before and after 70 per cent hepatectomy or complete bile duct ligation (CBDL). Changes in liver function were monitored by serial measurements of serum bilirubin, and by the maximum removal rate (Rmax) and plasma disappearance rate (ICG-K) of indocyanine green (ICG). Concentrations of CsA in whole blood were measured by HPLC. Seventy per cent hepatectomy caused significant liver dysfunction: the ICG-Rmax decreased by 47.7±7.1 per cent (mean±SD) and the ICG-K decreased by 61.3±9.7 per cent during the first week after hepatectomy. At the same time, the systemic clearance (CLs) of IV-CsA decreased by 43.9±8.2 per cent, the area under the concentration curve (AUC) of IV-CsA increased by 35.4±20.8 per cent and the bioavailability of CsA decreased by 26.4±14.8 per cent. CBDL also induced significant liver dysfunction: the ICG-Rmax decreased by 39.1±12.8 per cent and the ICG-K decreased by 65.6±3.6 per cent in the second week after the operation. During the same period, the AUC of PO-CsA decreased by 69.9±10.7 per cent and the bioavailability of CsA also decreased markedly by 73.9±15.6 per cent. These data indicate that hepatic impairment significantly influences the pharmacokinetics of CsA, not only by the changes in intestinal absorption, but also by those in hepatic, metabolism. Dose adjustment is therefore necessary in the presence of hepatic dysfunction in order to maintain an adequate blood concentration of CsA without causing side effects. This research was performed in the Department of Surgery, University of Pittsburgh Health Center, University of Pittsburgh, USA  相似文献   
3.
Experiments were performed to study the effect of verapamil on neuromuscular transmission and muscle contraction at a chick skeletal muscle-nerve preparation. In addition, the effects and interactions of verapamil with some muscle relaxants were studied in the same preparation. These effects were explored by studying the effects of verapamil on: directly-and indirectly-elicited twitch contractions, and neuromuscular blockade produced by gallamine and pancuronium. The results showed that verapamil (2-200 microM) had a differential effect on the twitch responses; more reductions occurred in the indirectly-elicited twitch tension, whereas the directly-elicited twitch response was reduced only by 20-30% of maximum indirectly-elicited twitch tension. Furthermore, in low concentrations (1-20 microM), verapamil significantly increased the neuromuscular blockade produced by gallamine (28-1280 nM) and pancuronium (18-573 nM). In high concentrations (greater than 200 microM), verapamil completely blocked the indirectly-elicited twitch response and produced a marked contracture in the chick skeletal muscle (1.0 +/- 0.1 g, n = 6). It was concluded that by reducing twitch tension and inhibiting neuromuscular transmission, verapamil increases (intensifies) neuromuscular blockade produced by muscle relaxants, e.g. gallamine and pancuronium.  相似文献   
4.
We describe a 35-year-old woman who developed parkinsonism in association with Addison's disease. The parkinsonism disappeared following treatment for Addison's disease without the use of antiparkinsonian drugs. This association stands unique although the pathophysiology remains unclear.  相似文献   
5.
A 42-year-old female presented with subarachnoid hemorrhage (SAH), presumably from a radiation-induced anterior communicating artery aneurysm. Six years earlier, she had undergone radiation treatment for an optic glioma that was diagnosed based on imaging criteria. The aneurysm was successfully clipped, and the optic glioma was biopsied to verify the diagnosis histologically. Radiation-induced cerebral aneurysms often manifest with a fatal SAH. These aneurysms typically develop in the field of radiation and are diagnosed a mean of 8.52 years after radiation. Rarely, the aneurysm sac thromboses spontaneously. Clipping or coiling of the aneurysm can be an effective treatment.  相似文献   
6.
7.
Surfactant protein C (SP-C) is a lung-specific, hydrophobic peptide found in organic extracts of pulmonary surfactant. Alveolar SP-C (3.5 kD) is produced from proteolytic cleavage of a larger precursor molecule (pro-SP-C; 21 kD). While SP-C is synthesized by type II cells, the pathways for processing and secretion have remained elusive due, in part, to the lack of monospecific antibodies against SP-C or its precursors. This report describes production and characterization of a new antibody directed against pro-SP-C epitopes. Polyclonal antisera (anti-CPRO-SP-C) was prepared using a synthetic peptide corresponding to a portion of rat SP-C cDNA sequence (Ile26-Ser72). This contained amino acids 3-35 of mature SP-C plus additional C-terminal residues (His59-Ser72). On Western blots, anti-CPRO-SP-C competitively reacted to CPRO-SP-C but not to mature SP-C. Immunoblots of in vitro synthesized pro-SP-C confirmed that the antisera also recognized native protein. Immunocytochemistry with anti-CPRO-SP-C demonstrated staining for pro-SP-C peptides in isolated type II cells as well as in alveolar epithelial cells of rat lung sections. Pro-SP-C preferentially co-localized to cells that stained positive for Maclura pomifera antigen. Anti-CPRO-SP-C staining was not observed in lung interstitium, pulmonary vasculature, or several control tissues (brain, heart, and liver were negative). Western blotting of subcellular fractions demonstrated pro-SP-C peptides in plasma membrane (20 kD) and microsomal (20 and 21 kD) fractions with a 16 kD peptide present in lamellar bodies. No pro-SP-C peptides were detected in purified surfactant. These results demonstrate the use of a synthetic peptide to generate specific antiserum against more hydrophilic domains of pro-SP-C sequences and confirm that SP-C propeptides are unique to the lung.  相似文献   
8.
Erythrocyte protoporphyrin and blood lead concentrations were measured in samples from 583 Saudi children attending the outpatient clinics. Erythrocyte protoporphyrin concentrations showed poor correlation with blood lead concentrations of 25 ug dl?1 and below. Measurement of erythrocyte protoporphyrin as a primary test for lead exposure is not recommended.  相似文献   
9.
The metabolic network in the yeast Saccharomyces cerevisiae was reconstructed using currently available genomic, biochemical, and physiological information. The metabolic reactions were compartmentalized between the cytosol and the mitochondria, and transport steps between the compartments and the environment were included. A total of 708 structural open reading frames (ORFs) were accounted for in the reconstructed network, corresponding to 1035 metabolic reactions. Further, 140 reactions were included on the basis of biochemical evidence resulting in a genome-scale reconstructed metabolic network containing 1175 metabolic reactions and 584 metabolites. The number of gene functions included in the reconstructed network corresponds to approximately 16% of all characterized ORFs in S. cerevisiae. Using the reconstructed network, the metabolic capabilities of S. cerevisiae were calculated and compared with Escherichia coli. The reconstructed metabolic network is the first comprehensive network for a eukaryotic organism, and it may be used as the basis for in silico analysis of phenotypic functions.  相似文献   
10.
Hard capsules are made of pure gelatin and small quantities of additives, including colouring agents permitted for use in food. In this study, the effects of three colouring agents (sunset yellow, quinoline yellow and erythrosine) on true and pseudo-cholinesterases (ChE) are assessed in erythrocytes and plasma, respectively. Results indicated that the synthetic compounds affected both true and pseudo ChE activity. The concentration of sunset yellow which caused 50% inhibition (IC50) of true ChE was about 64% that of pseudo-ChE; for erythrosine, IC50 was approximately the same for both true and pseudo-ChE; and for quinoline yellow, IC50 for true ChE was 25% of pseudo-ChE, although its effect on both true and pseudo-ChE was greater than seen with the other two dyes. Inhibitions of both true and pseudo-ChE were of mixed type (competitive and non-competitive). The enzyme-inhibitor dissociation constant (Ki) indicated that quinoline yellow was most potent and erythrosine was least potent out of the three compounds. Inhibition of both true and pseudo-ChE by each of the three dyes was abolished by dialysis, indicating that the effects were reversible.  相似文献   
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