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991.
992.
Allergen content in dust from homes and schools in northern Norway in relation to sensitization and allergy symptoms in schoolchildren 总被引:2,自引:0,他引:2
L. K. DOTTERUD T. D. VAN B. KVAMMEN† T. DYBENDAL‡ S. ELSAYED E. S. FALK 《Clinical and experimental allergy》1997,27(3):252-261
Background Previous studies have shown a high prevalence of atopic diseases among school children in the community of Sør-Varanger. Moreover, animal dander followed by pollen und house dust mite, were the most common allergens in skin prick tests. Objective To assess the allergen content in homes (living-rooms and mattresses) and classrooms of children living in an arctic area at 70° north. The presence of allergens in homes and schools and their relationship to atopy was of particular interest. Methods Dust samples from 38 homes and seven schools in northern Norway were collected by vacuum cleaning. The presence of allergens of dog, birch, timothy, Cladosporium herbanun, codfish and hen egg-white was investigated by radio-allergosorbent test (RAST) inhibition and the presence of major allergens of cat Felis domesticus (Fel d I) and house dust mites (HDM) Dermatophagoides pteronyssinus (Derp I) and Dermatophagoides farinae (Derf I) by enzyme-linked immunosorbent assay (ELISA). Results Mattresses contained significantly more dust per unit area than living-rooms and classrooms. No statistically significant differences in allergen content for dog. birch, timothy, Cladosporium, codfish and hen egg-white were seen between HDM-sensitized and non-atopic children. Most dust samples contained dog allergens with the highest allergenic activity found in living-rooms of those keeping dogs. An increased level of Feld I was detected in only one of 38 samples from living-rooms (this family kept a cat) and in 25 of 38 samples from mattresses with ranges from 24 to 84ng/m2. The highest concentrations were found in mattresses of children keeping cats. Increased levels ( 25 ng/m2) of Derp I were found only in homes and virtually only in mattresses of HDM-sensitized children. An increased level of Derf] was found in only one case, i.e. in the mattress of an HDM-sensitized child where additionally Der p I and HDMs were demonstrated microscopically. When relating Der p I to HDMsensitization an odds ratio of more than 16 (95% Cl: 1.6–394.3) was found. All extracts from living-rooms included codfish allergens. Low RAST inhibition values were detected for hen egg-white, Cladosporium, birch and timothy pollen in most samples. Furthermore, the study demonstrated that dust from schools was relatively free of allergens. Conclusion Previous findings indicating that the main allergen exposure problem in this geographical area is that of pet allergens were confirmed. 相似文献
993.
An indirect immunofluorescence assay using a cell culture-derived antigen for detection of antibodies to the agent of human granulocytic ehrlichiosis. 总被引:18,自引:11,他引:7 下载免费PDF全文
W L Nicholson J A Comer J W Sumner C Gingrich-Baker R T Coughlin L A Magnarelli J G Olson J E Childs 《Journal of clinical microbiology》1997,35(6):1510-1516
An indirect immunofluorescence assay for the detection of human antibodies to the agent of human granulocytic ehrlichiosis (HGE) was developed and standardized. Antigen was prepared from a human promyelocytic leukemia cell line (HL-60) infected with a tick-derived isolate of the HGE agent (USG3). Suitable antigen presentation and preservation of cellular morphology were obtained when infected cells were applied and cultured on the slide, excess medium was removed, and cells were fixed with acetone. Use of a buffer containing bovine serum albumin and goat serum reduced background fluorescence, and use of an immunoglobulin G (gamma-specific) conjugate reduced nonspecific binding. The assay readily detected specific antibody from HGE patients and did not detect antibody from healthy individuals. No significant reactivity was noted in sera from patients with high titers of antibodies to other rickettsial species. We were able to identify antibodies reactive to USG3 antigen in samples from areas where HGE is endemic that had tested negative to other rickettsial agents. Animal sera reactive against Ehrlichia equi or Ehrlichia phagocytophila bound to the HGE antigen, indicating that the assay may be useful for veterinary use. Comparability between two different laboratories was assessed by using coded human sera exchanged between laboratories. Results from the two laboratories were similar, indicating that the assay can be easily integrated into use for routine testing for HGE. The assay was then compared to an assay using horse neutrophils infected with ehrlichiae. The two assays gave comparable results, indicating that the cell culture-derived antigen can be used for testing samples that have been previously tested with E. equi as an antigen. The new assay offers several advantages over other immunofluorescence methods that use animal-derived antigen and is suitable for use in testing for human antibodies to the HGE agent. 相似文献
994.
The experimental and clinical results of the self-expanding nitinol coil stent have been reviewed. Animal data have shown that the stent is safe and provokes a mild proliferative response, similar to previously studied balloon-expandable stents. Data from femoral and popliteal arteries are supportive of long-term patency in these arteries, which are typically associated with unfavorable results from other stents. Data from coronary implantations in patients show that the stent can be safely used to treat coronary lesions of both simple and complex natures. Long-term results of these patients compare favorably with existing data in similar lesions using other stents. A larger clinical trial using the new flat wire design stent is required to test whether further stent expansion may contribute to low restenosis rates. 相似文献
995.
Psychometric data are presented which examine the validity of using the concentration of benzoylecgonine in urine, a major metabolite of cocaine, as a measure of drug use, in studies of drug abuse treatments. In such research the standard biological indicator of drug use is usually a qualitative urine drug test, which merely indicates the presence or absence of a drug or its metabolite. A quantitative (i.e. continuous) outcome measure, such as the concentration of a drug or its metabolite in a biological fluid, has substantially more statistical power than a dichotomous measure and should, therefore, prove a more sensitive measure of drug use when viewed from a measurement perspective. Data from two placebo-controlled clinical trials of fluoxetine as an adjunct to treatment for cocaine abuse are analyzed to address this issue. Results indicate that urine benzoylecgonine level is closely related to self-reports of drug use and is independent of levels of anxiety, depression and hopelessness. 相似文献
996.
Doing it right the first time: quality improvement and the contaminant blood culture. 总被引:5,自引:3,他引:2 下载免费PDF全文
F I Weinbaum S Lavie M Danek D Sixsmith G F Heinrich S S Mills 《Journal of clinical microbiology》1997,35(3):563-565
The aim of the project was to determine whether the rate of contaminant blood cultures could be reduced by using a team of dedicated phlebotomists. Comparisons were made between adult patients requiring blood cultures for suspected bacteremia on medical and surgical units before and after the introduction and withdrawal of a dedicated blood culture team. The results showed that a significant reduction in the contaminant blood culture rate was achieved by the blood culture team (P < 0.001; chi(2) test). Therefore, in our experience, the rate of contaminant blood cultures can be reduced in a teaching hospital by using a team of dedicated phlebotomists. Calculations made with our data and those published by others suggest that cost savings from reducing false-positive blood cultures are greater than the cost of the blood culture team. 相似文献
997.
Beta2-glycoprotein I-dependent anticardiolipin antibody in early recurrent spontaneous abortion 总被引:1,自引:1,他引:0
Maejima M; Fujii T; Okai T; Kozuma S; Shibata Y; Taketani Y 《Human reproduction (Oxford, England)》1997,12(10):2140-2142
The objective of this study was to assess the clinical significance of
autoimmune anticardiolipin antibody that can react with cardiolipin only in
the presence of beta2-glycoprotein I (beta2-glycoprotein I- dependent
anticardiolipin antibody) in the pathogenesis of early recurrent abortion.
A total of 72 early recurrent spontaneous aborters and 175 normal healthy
women were analysed for the occurrence of beta2- glycoprotein I-dependent
anticardiolipin antibody in serum samples by an enzyme-linked immunosorbent
assay specific for the detection of beta2-glycoprotein I-dependent
anticardiolipin antibody. The incidence of beta2-glycoprotein I-dependent
anticardiolipin antibody in the early recurrent spontaneous aborters was
essentially the same as that of normal women. Thus, the beta2-glycoprotein
I-dependent anticardiolipin antibody seemed to have little, if any,
implication in the pathogenesis of early recurrent spontaneous abortion.
相似文献
998.
M. D. Mashkovskii V. A. Parshin R. B. Parimbetova 《Bulletin of experimental biology and medicine》1997,123(3):257-259
It is found that the cholinomimetic aceclidine stimulates learning and memory processes and exerts antiamnestic effect in
rats with conditioned avoidance reaction. The effect of aceclidine is not inferior to that of amiridin and surpasses that
of physostigmine.
Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 123, No. 3, pp. 296–298, March, 1997 相似文献
999.
1000.
Engineering human immunodeficiency virus 1 protease heterodimers as macromolecular inhibitors of viral maturation. 总被引:3,自引:0,他引:3 下载免费PDF全文
F McPhee A C Good I D Kuntz C S Craik 《Proceedings of the National Academy of Sciences of the United States of America》1996,93(21):11477-11481
Dimerization of human immunodeficiency virus type 1 protease (HIV-1 PR) monomers is an essential prerequisite for viral proteolytic activity and the subsequent generation of infectious virus particles. Disruption of the dimer interface inhibits this activity as does formation of heterodimers between wild-type and defective monomers. A structure-based approach was used to identify amino acid substitutions at the dimer interface of HIV-1 PR that facilitate preferential association of heterodimers and inhibit self-association of the defective monomers. Expression of the designed PR monomers inhibits activity of wild-type HIV-1 PR and viral infectivity when assayed in an ex vivo model system. These results show that it is possible to design PR monomers as macromolecular inhibitors that may provide an alternative to small molecule inhibitors for the treatment of HIV infection. 相似文献