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排序方式: 共有269条查询结果,搜索用时 15 毫秒
1.
L G Yamamoto G J Gainsley J E Witek 《JPEN. Journal of parenteral and enteral nutrition》1986,10(5):535-539
The use of parenteral nutrition is becoming more widespread. The need for individualized parenteral nutrition solutions in pediatric patients makes the ordering and preparation of these solutions more complex and error-prone. A computer program is described which performs comprehensive management of parenteral nutrition by assisting in accurately ordering and preparing parenteral nutrition solutions. It also performs extensive error-checking and provides additional nutritional information. Data base management is also a feature which permits future large scale analysis of parenteral nutrition data for research purposes. This program, designed to run on a personal computer, is very comprehensive, yet flexible and user-friendly. 相似文献
2.
Eugenija Zuskin E. Neil Schachter Bozica Kanceljak Jadranka Mustajbegovic Theodor J. Witek 《International archives of occupational and environmental health》1994,66(5):317-324
The relationship of skin reactivity and serum immunoglobulin E (IgE) levels to the prevalence of chronic respiratory symptoms and to ventilatory capacity is examined in workers exposed to different organic aerosols. The results from group of control workers similarly tested are also presented. Workers exposed to occupational allergens had positive skin tests more frequently than did controls, except for soy bean workers. Workers with positive skin tests to occupational allergens had a higher prevalence of almost all symptoms than those with negative skin tests although the differences did not always reach statistical significance. Workers with positive skin reactions in general had significantly higher serum IgE levels than did workers with negative skin reactions. There were across-shift reductions of ventilatory capacity in all groups of exposed workers, varying for forced vital capacity from 1.7% to 13.3%, for forced expiratory volume from 0.4%–21.9%, for maximum flow rates at 50% from 1.5% to 16.1% and for maximum flow rates at the last 25% of control vital capacity from 0% to 24.9%. There was, however, no correlation between acute and chronic lung function changes and skin reactivity or IgE values. Our data suggest that although exposure to organic aerosols may be associated with frequent immunologic reactions, these findings do not predict objective respiratory impairment.The research was supported in part by grant no. JBP 733 from the National Institutes of Health, Bethesda, Md., USA, and by grant no. RO1 OHO-2593-04 from the National Institutes of Occupational Safety and Health, Centers for Disease Control, Atlanta, Ga., USA 相似文献
3.
Although the effect of IL-15 has been described on murine cells in vitro and in vivo, its effect on human memory CD8(+) T cells is not well characterized. We show here that IL-15 preferentially enhances the activation and effector function of human effector-memory CD45RA(-)CD62L(-) and CD45RA(+)CD62L(-) CD4(+) and CD8(+) T cells in both healthy and HIV-infected individuals. We find that IL-15 increases 2- to 5-fold both the activation and secretion of the effector cytokines IFN-gamma and tumor necrosis factor (TNF)-alpha by anti-CD3-stimulated purified CD4(+) and CD8(+) T cells and peripheral blood mononuclear cells from healthy and HIV-infected individuals. Furthermore, IL-15 potently inhibits CD95/Fas-induced apoptosis of the effector-memory CD4(+) and CD8(+) T cells from HIV-infected individuals. These findings suggest that in addition to being a growth and survival factor for memory CD8(+) T cells, IL-15 is also a potent activator of human effector-memory CD8(+) T cells both in healthy and in HIV-infected individuals. 相似文献
4.
Medicaid spending is an increasing burden on already stressed state budgets. The states find themselves trapped between these growing costs and mounting pressure to ensure access of the underserved to health care services. States are hopeful that managed care is the answer to meeting the seemingly diametric needs of reducing costs while increasing access. However, evidence of performance measured in cost, access, and quality, and financial viability is inconclusive. Nevertheless, there have been some successes and, clearly, Medicaid managed care has potential. The unanswered question is the extent to which states can meet the diverse challenges of both Medicaid and managed care and tap that potential. 相似文献
5.
The lung function response to inhalation of an extract of green coffee was studied in ten healthy subjects who were prescreened for airway hyperresponsiveness to an aerosol of green coffee extract. The effects of this provocation were evaluated at rest and following moderate exercise as well as with and without pretreatment with 80 mg of disodium cromoglycate (DSCG). There was a statistically significant decrement in lung function over time (P less than .001) following coffee provocation both at rest and following exercise. No significant protection against this response was observed with DSCG pretreatment. While the majority of these "healthy" coffee reactors exhibited baseline nonspecific airway hyperresponsiveness to methacholine (PC20 FEV1 less than 25 mg/mL in 7/10), there was no correlation in these ten subjects between baseline responsiveness to methacholine and the degree of lung function decrement following coffee (P greater than .05). Also, no correlation was observed between skin prick and lung function response to coffee extract. We conclude that inhalation of green coffee extract causes significant bronchoconstriction in selected healthy volunteers and that this response is not prevented by pretreatment with DSCG. 相似文献
6.
7.
Smoking and cotton dust effects in cotton textile workers 总被引:1,自引:0,他引:1
Cotton textile workers have an increased prevalence of both obstructive and restrictive lung function patterns compared with control subjects. Similar abnormal patterns may occur with respiratory diseases of other etiologies, notably those associated with cigarette smoking. The shape of the maximum expiratory flow volume (MEFV) curve has been used to characterize patterns of lung function abnormality. To better evaluate the respiratory effects of cotton dust exposure and to contrast them with those of cigarette smoking, we defined a new functional parameter (angle beta) related to the shape of the MEFV curve. We compared 477 cotton textile workers, both current smokers and never smokers, 45 years and older, with 932 similarly aged control subjects from three communities. Smokers, regardless of their occupational exposure or sex, have smaller beta values than nonsmokers. Cotton textile workers, despite a greater prevalence of abnormal lung function, have beta values that do not differ from those of persons without occupational exposure to cotton dust. We suggest that morphologic patterns of flow volume curves reflect separate effects of cotton dust exposure and smoking and may be related to different sites of airway injury. 相似文献
8.
9.
The spirometric efficacy of once-daily dosing with tiotropium in stable COPD: a 13-week multicenter trial. The US Tiotropium Study Group 总被引:12,自引:0,他引:12
STUDY OBJECTIVE: To compare the bronchodilator efficacy and safety of tiotropium and placebo. DESIGN: A 3-month, randomized, double-blind, placebo-controlled, multicenter trial. SETTING: Outpatient. PATIENTS: Four hundred seventy patients with stable COPD (mean FEV(1) = 38.6% predicted). INTERVENTIONS: Tiotropium 18 microg (N = 279) or placebo (N = 191) given once daily via a lactose-based dry-powder inhaler device. Measurements and results: Spirometry was evaluated on days 1, 8, 50, and 92. Data were expressed as the mean trough (ie, before morning dose; 23 to 24 h after previous dose) and average response observed in the 3 h after the dose was received. Tiotropium produced significant improvement in trough FEV(1) and FVC, averaging 12% greater than baseline on day 8; these improvements were maintained on days 50 and 92. The average postdose FEV(1) was 16% greater than baseline on day 1 and 20% greater than baseline on day 92; FVC was 17% greater than baseline on day 1 and 19% greater than baseline on day 92. Tiotropium was significantly more effective than placebo in both trough and average FEV(1) and FVC response (p < 0.001). These spirometric effects were corroborated by significant improvements in daily morning and evening peak expiratory flow rate, as well as a reduction in "as-needed" albuterol use. Symptoms of wheezing and shortness of breath were significantly less in patients receiving tiotropium, and the physician global assessment noted overall improvements with those treated with tiotropium relative to placebo. The most common reported adverse event after tiotropium was dry mouth (9.3% vs 1.6% relative to placebo; p < 0.05). CONCLUSIONS: These data demonstrate that tiotropium is a safe and effective once-daily anticholinergic bronchodilator and should prove useful as first-line maintenance therapy in COPD. 相似文献
10.
Simone Susser Mathieu Flinders Henk W. Reesink Stefan Zeuzem Glenn Lawyer Anne Ghys Veerle Van Eygen James Witek Sandra De Meyer Christoph Sarrazin 《Antimicrobial agents and chemotherapy》2015,59(5):2746-2755
In treating hepatitis B virus (HBV) and human immunodeficiency virus (HIV) infections, the rapid reselection of resistance-associated variants (RAVs) is well known in patients with repeated exposure to the same class of antiviral agents. For chronic hepatitis C patients who have experienced virologic failure with direct-acting antiviral drugs, the potential for the reselection of persistent RAVs is unknown. Nine patients who received 14 days of telaprevir monotherapy were retreated with telaprevir-based triple therapy 4.3 to 5.7 years later. In four patients with virologic failure with both telaprevir-containing regimens, population-based and deep sequencing (454 GS-FLX) of the NS3 protease gene were performed before and at treatment failure (median coverage, 4,651 reads). Using deep sequencing, with a threshold of 1.0% for variant calling, no isolates were found harboring RAVs at the baseline time points. While population-based sequencing uncovered similar resistance patterns (V36M plus R155K for subtype 1a and V36A for subtype 1b) in all four patients after the first and second telaprevir treatments, deep sequencing analysis revealed a median of 7 (range, 4 to 23) nucleotide substitutions on the NS3 backbone of the resistant strains, together with large phylogenetic differences between viral quasispecies, making the survival of resistant isolates highly unlikely. In contrast, in a comparison of the two baseline time points, the median number of nucleotide exchanges in the wild-type isolates was only 3 (range, 2 to 8), reflecting the natural evolution of the NS3 gene. In patients with repeated direct antiviral treatment, a continuous evolution of HCV quasispecies was observed, with no clear evidence of persistence and reselection but strong signs of independent de novo generation of resistance. Antiviral therapy for chronic viral infections, like HIV, hepatitis B virus (HBV), or hepatitis C virus (HCV), faces several challenges. These viruses have evolved survival strategies and proliferate by escaping the host''s immune system. The development of direct-acting antiviral agents is an important achievement in fighting these infections. Viral variants conferring resistance to direct antiviral drugs lead to treatment failure. For HIV/HBV, it is well known that viral variants associated with treatment failure will be archived and reselected rapidly during retreatment with the same drug/class of drugs. We explored the mechanisms and rules of how resistant variants are selected and potentially reselected during repeated direct antiviral therapies in chronically HCV-infected patients. Interestingly, in contrast to HIV and HBV, we could not prove long-term persistence and reselection of resistant variants in HCV patients who failed protease inhibitor-based therapy. This may have important implications for the potential to reuse direct-acting antivirals in patients who failed the initial direct antiviral treatment. (The phase IIIb study described in this paper is registered at ClinicalTrials.gov under registration number .) NCT01054573相似文献