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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   
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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   
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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   
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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   
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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   
7.
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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Abstract

Amniotic membrane has the potential to be used as scaffold in various tissue engineering applications. However, increasing its biostability at the same time maintaining its biocompatibility is important to enhance its usage as a scaffold. This studied characteristics genipin-crosslinked amniotic membrane as a bioscaffold. Redundant human amniotic membranes (HAM) divided into native (nAM), decellularized (dAM) and genipin-crosslinked (clAM) groups. The dAM and clAM group were decellularized using thermolysin (TL) and sodium hydroxide (NaOH) solution. Next, clAM group was crosslinked with 0.5% and 1.0% (w/v) genipin. The HAM was then studied for in vitro degradation, percentage of swelling, optical clarity, ultrastructure and mechanical strength. Meanwhile, fibroblasts isolated from nasal turbinates were then seeded onto nAM, dAM and clAM for biocompatibility studies. clAM had the slowest degradation rate and were still morphologically intact after 30 days of incubation in 0.01% collagenase type 1 solution. The dAM had a significantly highest percentage of swelling than other groups (p?<?0.05). Besides, the dAM retained the collagen content at similar level of nAM. Although the dAM had highest mechanical strength compared to the rest of the groups, the differences were statistically insignificant. Cell attachment on dAM and 0.5% clAM was higher compared to that on nAM and 1.0% clAM. In conclusion, clAM have better biostability and biocompatibility compared to the nAM and dAM. Together with other suitable characteristics of the clAM such as percentage of swelling, structural integrity and ECM content, clAM is suitable as scaffold for various tissue engineering applications.  相似文献   
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