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991.
Iossifova YY Reponen T Bernstein DI Levin L Kalra H Campo P Villareal M Lockey J Hershey GK LeMasters G 《Allergy》2007,62(5):504-513
BACKGROUND: (1-3)-Beta-D-glucan is a fungal cell wall component, suspected to cause respiratory symptoms in adults. However, very little is known on the possible health effects of (1-3)-beta-D-glucan during infancy. We examined the association between (1-3)-beta-D-glucan exposure and the prevalence of allergen sensitization and wheezing during the first year of life in a birth cohort of 574 infants born to atopic parents. Endotoxin exposure was included as a possible confounder. METHODS: (1-3)-Beta-D-glucan and endotoxin exposures were measured in settled dust collected from infants' primary activity rooms. The primary outcomes at approximately age one included parental reports of recurrent wheezing and allergen sensitization evaluated by skin prick testing to a panel of 15 aeroallergens as well as milk and egg white. RESULTS: Exposure to high (1-3)-beta-D-glucan concentration (within fourth quartile) was associated with reduced likelihood of both recurrent wheezing [adjusted OR (aOR) = 0.39, 95% CI = 0.16-0.93] and recurrent wheezing combined with allergen sensitization (aOR = 0.13, 95% CI = 0.03-0.61). Similar trends were found between (1-3)-beta-D-glucan concentrations and allergen sensitization (aOR = 0.57, 95% CI = 0.30-1.10). In contrast, recurrent wheezing with or without allergen sensitization was positively associated with low (1-3)-beta-D-glucan exposure within the first quartile (aOR = 3.04, 95% CI = 1.25-7.38; aOR = 4.89, 95% CI = 1.02-23.57). There were no significant associations between endotoxin exposure and the studied health outcomes. CONCLUSIONS: This is the first study to report that indoor exposure to high levels of (1-3)-beta-D-glucan (concentration >60 microg/g) is associated with decreased risk for recurrent wheezing among infants born to atopic parents. This effect was more pronounced in the subgroup of allergen-sensitized infants. 相似文献
992.
Vesper SJ McKinstry C Haugland RA Iossifova Y Lemasters G Levin L Khurana Hershey GK Villareal M Bernstein DI Lockey J Reponen T 《Journal of exposure science & environmental epidemiology》2007,17(1):88-94
The results of a traditional visual mold inspection were compared to a mold evaluation based on the Relative Moldiness Index (RMI). The RMI is calculated from mold-specific quantitative PCR (MSQPCR) measurements of the concentration of 36 species of molds in floor dust samples. These two prospective mold evaluations were used to classify the mold condition in 271 homes of infants. Later, the development of respiratory illness was measured in the infants living in these homes and the predictive value of each classification system was evaluated. The binary classification of homes as either moldy or non-moldy by on-site visual home inspection was not predictive of the development of respiratory illness (wheeze and/or rhinitis) (P=0.27). Conversely, a method developed and validated in this paper, using the RMI index fit to a logistic function, can be used to predict the occurrence of illness in homes and allows stake-holders the choice among various levels of risk. 相似文献
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994.
OBJECTIVE: We examined differences in preferences for the EQ-5D health states among blacks, Hispanics, and others living in the United States. STUDY DESIGN AND SETTING: A multi-stage probability sample was selected from the adult U.S. population. Each respondent valued a subset of the 243 EQ-5D health states. Regression analysis was used to analyze differences in mean valuations for 13 health states among the racial/ethnic groups. First, we compared unadjusted mean valuations among the three groups. Second, we evaluated differences in mean valuations among the groups after adjusting for other sociodemographic characteristics. Third, we evaluated the impact of race/ethnicity on estimates derived from the U.S. health state valuation (i.e., D1) model. RESULTS: Valuations differed among the groups for seven of the 13 health states, and these differences persisted after adjusting for other sociodemographic factors. Blacks appeared to perceive extreme health problems to be associated with less disutility than did members of the other two groups. CONCLUSION: Within the United States, there exist racial/ethnic differences in the perceived desirability of the EQ-5D health states that cannot be readily explained by socioeconomic disparities. 相似文献
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A placebo-controlled trial of topical 8% arildone cream early in recurrent genital herpes. 下载免费PDF全文
J M Douglas Jr F N Judson M J Levin J A Bosso S L Spruance J M Johnston L Corey J A McMillan L B Weiner J A Frank Jr 《Antimicrobial agents and chemotherapy》1986,29(3):464-467
Arildone is an aryl diketone which is inhibitory in vitro against herpes simplex virus type 2 at a concentration of 2 micrograms/ml or less. One hundred forty-five patients with recurrent genital herpes were enrolled in a multicenter, randomized, placebo-controlled, double-blind trial to evaluate the efficacy and safety of an 8% arildone cream. Patients initiated therapy a mean of 9.9 h and a maximum of 24 h after the reported onset of lesions and applied medication 6 times daily for 7 days. The duration of viral shedding was shorter among women (P less than 0.05) and the duration of local itching was shorter among men (P less than 0.05) in patients that received arildone than in those that received placebo, but there were no significant differences between treatment groups in duration of pain, time to crusting or healing of lesions, or percentage of patients developing new lesions. Mild local irritation after application of ointment was common and occurred equally in both treatment groups. Despite early application, topical arildone cream was ineffective in the therapy of acute recurrences of genital herpes. 相似文献
999.
P. B. Baines A. P. J. Thomson J. A. Sills C. A. Hart Britto J. Arends N. Oragui E. Ajayi-obe D. Nadel S. Habibi P. Levin M. P. B. Baines S. Stanford D. Bishop-Bailey A. P. J. Thompson J. A. Mitchell C. A. Hart A. J. Petros Yeung S. Nadel S. Levin M. G. Turner R. Taylor Nadel S. Newport M. J. Booy R. Levin M. J. E. Fischen J. C. Fischer G. Printzen E. Schmid D. Nadal S. Fanconi Widjajanti M. Dhamhur Halimun E. M. Mulyo D. G. 《Intensive care medicine》1996,22(2):S163-S164
1000.
Platelet aggregation by adenosine diphosphate (ADP) is a self-limited and reversible process. An application of this phenomenon is described which allows removal of the platelets from large volumes of fresh platelet rich plasma (PRP) for the preparation of platelet concentrates. The macroscopic platelet clumps resulting from a concentration of 10 μgm ADP per ml of PRP are removed by centrifugation at 50 × g for 10 minutes. Resuspension of these platelets in 20 cc of native plasma results in a platelet concentrate that is 80 to 90 per cent as effective per unit as PRP in its ability to elevate the platelet count in recipients. Such concentrates are superior to concentrates prepared by other methods. The posttransfusion survival of ADP platelets compares favorably with the survival of platelets administered as PRP. There is evidence of minor sequestration but there is no apparent irreversible damage to platelets handled in this manner. Alkaline plasma and increase in plasma ionized calcium enhance the ADP aggregation and improve the efficiency of in vitro separation of platelets from PRP. However, the resulting concentrate is less effective in vivo, because of prolonged and slowly reversible clumping, and failure of these platelets to circulate. 相似文献