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排序方式: 共有1036条查询结果,搜索用时 31 毫秒
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Milos Jesenak MD PhD Peter Banovcin MD PhD Zuzana Rennerova MD PhD Lubica Jakusova MD PhD Zuzana Havlicekova MD PhD Vladimir Pohanka MD PhD MPH FCCP Maria Pia Villa MD PhD Roberto Ronchetti MD PhD 《International journal of dermatology》2009,48(9):941-946
Background The atopy patch test (APT) is no longer an experimental method; it is increasingly being used as a standard diagnostic tool for the characterization of patients with aeroallergen- and food-triggered disorders. Some technical aspects of this test still remain to be answered. We aimed to study the reproducibility of this test over time in the general child population.
Methods In a general population of 118 children, we investigated the reproducibility of duplicate APTs with four food allergens in their native form, which were repeated at set intervals from the first test: 7 days (group 1), 14 days (group 2), and 21 days (group 3).
Results We observed very poor reproducibility on both sides of the back in all three studied subgroups. The reproducibility rates and Cohen's κ values did not improve when we did not consider the side of the back. There were no differences in the prevalence of atopy between the subjects with reproducible and nonreproducible APT results. All three groups studied showed no difference in the prevalence rates of atopy. There was no relationship between APT and skin prick test positivity for the same allergen. Questionnaire-derived data about previous food-related reactions did not help in the evaluation of the doubtful nonreproducible APT results with food allergens.
Conclusions Our results show that the reproducibility of food APTs is poor and unsatisfactory over time, and there is an urgent need for the development of optimal, stable, and good-quality APT testing substances. 相似文献
Methods In a general population of 118 children, we investigated the reproducibility of duplicate APTs with four food allergens in their native form, which were repeated at set intervals from the first test: 7 days (group 1), 14 days (group 2), and 21 days (group 3).
Results We observed very poor reproducibility on both sides of the back in all three studied subgroups. The reproducibility rates and Cohen's κ values did not improve when we did not consider the side of the back. There were no differences in the prevalence of atopy between the subjects with reproducible and nonreproducible APT results. All three groups studied showed no difference in the prevalence rates of atopy. There was no relationship between APT and skin prick test positivity for the same allergen. Questionnaire-derived data about previous food-related reactions did not help in the evaluation of the doubtful nonreproducible APT results with food allergens.
Conclusions Our results show that the reproducibility of food APTs is poor and unsatisfactory over time, and there is an urgent need for the development of optimal, stable, and good-quality APT testing substances. 相似文献
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Renate A. Morawetz G. Paolo Rizzardi Didier Glauser Olivier Rutschmann Bernard Hirschel Luc Perrin Milos Opravil Markus Flepp Jan von Overbeck Michel P. Glauser Silvia Ghezzi Elisa Vicenzi Guido Poli Adriano Lazzarin 《European journal of immunology》1997,27(12):3223-3227
Homozygous (Δccr5/Δccr5) and heterozygous (CCR5/Δccr5) deletions in the β-chemokine receptor 5 (CCR5) gene, which encodes for the major co-receptor for macrophage-tropic HIV-1 entry, have been implicated in resistance to HIV infection and in protection against disease progression, respectively. The CCR5/Δccr5 genotype was found more frequently in long-term nonprogressors (LTNP) (31.0%) than in progressors (10.6%, p < 0.0001), in agreement with previous studies. Kaplan-Meier survival analyses showed that a slower progression of disease, i.e. higher proportion of subjects with CD4+ T cell counts >500/μl (p = 0.0006) and a trend toward a slower progression to AIDS (p = 0.077), was associated with the CCR5/Δccr5 genotype. However, when LTNP were analyzed separetely, no significant differences in CD4+ T cell counts (p = 0.12) and viremia levels (p = 0.65) were observed between the wild-type (69 % of LTNP) and the heterozygous (31.0 %) genotypes. Therefore, there are other factors which play a major role in determining the status of nonprogression in the majority of LTNP. Furthermore, there was no evidence that the CCR5/Δccr5 genotype was associated with different rates of disease progression in the group of progressors. Taken together, these results indicate that the CCR5/Δccr5 genotype is neither essential nor sufficient for protection against the progression of HIV disease. 相似文献
6.
Schüpbach J Böni J Bisset LR Tomasik Z Fischer M Günthard HF Ledergerber B Opravil M;Swiss HIV Cohort Study 《Journal of acquired immune deficiency syndromes (1999)》2003,33(3):292-299
An HIV-1 p24 antigen test involving signal amplification-boosted ELISA of heat-denatured plasma was evaluated prospectively in 55 patients whose viral RNA in plasma had previously been suppressed for at least 6 months under antiretroviral combination therapy. During a median follow-up of 504 days, CD4 counts increased by a median of 62 cells per year. By univariate and multivariate linear regression analysis, the level of p24 antigen as expressed by the absorbance/cutoff ratio was a significant inverse correlate of both the CD4 count in a sample (p =.013) and its annual change in a patient (p <.0001). The p24 antigen retained significance even among 48 individuals whose HIV-1 RNA, apart from occasional blips, remained below 400 copies/mL. Batch-wise retesting of 70 samples from 5 such patients with a further improved procedure showed measurable p24 antigen in all but 1 sample and an inverse correlation with both the CD4 count (p =.0331) and percentage (p <.0001), thus confirming the prospectively generated data. Comparison of p24 antigen and HIV-1 RNA concentrations indicate that the p24 antigen detected in these samples is not associated with viral RNA-containing particles and may originate from other compartments of virus expression. 相似文献
7.
Nadine C. Milos Yanling Ma Parag V. Varma Michael P. Bering Zarina Mohamed Linda M. Pilarski Yvette N. Frunchak 《Anatomy and embryology》1990,182(4):319-327
Summary A monoclonal antibody has been produced againstXenopus laevis galactoside-binding neural-creststage lectin. This antibody inhibits lectin-mediated hemagglutination. Using this antibody
in conjunction with immunohistochemical techniques, lectin deposition has been studied in embryos and tadpoles at different
stages of morphogenesis, from initial neural crest migration, up to the formation of a swimming tadpole. Lectin levels change
during development in different regions of the embryo and tadpole, decreasing in migratory cells, and increasing in sites
where cells become more adhesive to one another. The results suggest that galactoside-binding lectins may be an important
class of cellular adhesion molecules during these stages of development. 相似文献
8.
Dara L. Hoffman James A. Owen Milos Chvapil 《Experimental and molecular pathology》1983,39(2):154-162
β-Aminopropionitrile as free base (BAPN) was applied onto the incised or intact skin of rats at the dose of 5, 20, 100, and 200 μl for 9 days, twice daily. Breaking strength of the skin wound or intact skin was significantly reduced at doses of 20 μl and higher; body weight growth was significantly retarded at the two highest dosages. It is concluded that at a given dose (20 μl) collagen polymerization (evaluated by reduced breaking strength and increased extractability of collagen) was specifically inhibited by BAPN. Furthermore, no evidence of topical or general toxic effects were observed, as reflected in histology, body weight growth, and behavior of the rats. Acute LD50 of BAPN base and fumarate, administered either ip or topically, was determined in mice. While BAPN base in ip administration shows LD50 of 1.15 g/kg, in cutaneous application it is more than 12.8 g/kg. It is suggested that topically applied BAPN base is percutaneously absorbed and affects collagen polymerization in the skin and adjacent tissues. 相似文献
9.
Efficacy and safety of imatinib mesylate in advanced gastrointestinal stromal tumors 总被引:1,自引:0,他引:1
10.
Postnatal mice lacking neurotrophin-3 (NT3) are deficient in Merkel cells of touch domes and whisker follicles. We examined the mechanism of Merkel cell loss by immunocytochemistry and electron microscopy. Merkel cell of whisker follicles of NT3 null newborns exhibited decreased immunoreactivity for cytokeratin 8 and contained apoptotic bodies that were positive for cleaved caspase-3, a marker of active apoptosis. By electron microscopy, the Merkel cells displayed aggregation of chromatin along the nuclear membrane, with the marginated chromatin forming caps at the periphery of the nucleus. Ribosomes aggregated in the cytoplasm, while dense core granules characteristic of Merkel cells were still discernible. Finally, the Merkel cells and their nuclei fragmented into apoptotic bodies. None of the apoptotic Merkel cells were contacted by nerve fibers, and their desmosomal contacts with surrounding keratinocytes disappeared. After postnatal day 6 apoptotic Merkel cells were no longer observed, and the number of surviving Merkel cells was severely reduced. They were flat and contained few osmiophilic granules. We conclude that perinatal apoptosis is responsible for the loss of Merkel cells lacking innervation in NT3 null mice. 相似文献