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排序方式: 共有1371条查询结果,搜索用时 15 毫秒
1.
Exhaled nitric oxide in children with allergic rhinitis: A potential biomarker of asthma development
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D L Jacobson B E Allman P J McMahon K A Nugent D Paganin M Arif S A Werner 《Applied radiation and isotopes》2004,61(4):547-550
In this paper, we will discuss a phase-contrast imaging method that avoids the complications of interferometry to provide phase contrast in weakly absorbing samples. A transversely coherent neutron beam is used with the traditional radiography scheme. Images taken with this scheme show dramatic intensity variations due to sharp changes in the neutron wave refractive index. With some numerical processing these images may be used to reconstruct a quantitative phase radiograph of specimens imaged with this technique. 相似文献
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Maddalena Castellani Pastoris Dr. Biol. Elisabeta Volpi P. Benedetti M.D. D. Greco M.D. N. Billo M.D. MPH Prof. F. J. Fehrenbach M.D. Ingeburg Horbach M.D. P. Hohl M.D. Prof. G. Wewalka M.D. 《Infection》1992,20(2):73-77
Summary The detection of travel-associated legionellosis can be extremely difficult; hence, an extensive case investigation is recommended in pneumonia-striken travellers and tourists, who are particularly at risk of acquiring the disease. On the Island of Ischia (Isola d'Ischia, Naples, Italy) a total of six cases of Legionnaires' disease occurred from 1986 to 1990. All patients (one man and two women from Germany, one Austrian woman, one Swiss man, and one Italian woman) had taken thermal baths and stayed in local hotels; they all experienced severe pneumonia, and three of them died. These cases were associated with hotels, and the hot-water supply was presumed to have transmitted the infection. Remedial procedures were applied to the hot-water plumbing of the hotels according to the WHO recommendations and were proved to be effective. The occurrences described in this paper stress the importance of rapid and accurate reporting of diagnosed cases to the country where the infection was probably acquired, in order to ensure early detection of endemic foci and emerging clusters of legionellosis.
Sechs Fälle von reiseassoziierter Legionärskrankheit in Ischia unter Beteiligung von vier Ländern
Zusammenfassung Der Nachweis reiseassoziierter Legionärskrankheit gestaltet sich häufig schwierig. Eine Überwachung von Touristen und Reisenden, die ein erhöhtes Legionellose-Risiko haben, ist daher zu empfehlen. Zwischen 1986 und 1990 traten auf der Insel Ischia (Neapel, Italien) insgesamt sechs Fälle von Legionärskrankheit auf. Alle Patienten (ein Mann und zwei Frauen aus Deutschland, eine Österreicherin, ein Schweizer und eine Italienerin), die in Hotels auf der Insel wohnten, hatten Thermalbäder besucht. Sie erkrankten an schweren Pneumonien, wobei drei Todesfälle auftraten. Die Ansteckungsquelle konnte mit Hotels in Verbindung gebracht werden, wobei die Übertragung der Infektion über die Warmwasserleitungsnetze als gesichert anzunehmen war. Desinfektionsmaßnahmen in den betreffenden Hotels, die nach den Empfehlungen der WHO ausgeführt wurden, erwiesen sich als wirksam. Das genannte Infektionsgeschehen weist auf die Notwendigkeit hin, Fälle von Legionärskrankheit so rasch wie möglich dem Ursprungsland unter Angabe der vermuteten Infektionsquelle zu melden, um sicherzustellen, daß eine Früherkennung endemischer Herde bzw. assoziierter Legionellosen bekannt gemacht wird.相似文献
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Identification of a Promiscuous T-Cell Epitope in Mycobacterium tuberculosis Mce Proteins 总被引:4,自引:0,他引:4
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Maddalena Panigada Tiziana Sturniolo Giorgio Besozzi Maria Giovanna Boccieri Francesco Sinigaglia Giuliana Gialdroni Grassi Fabio Grassi 《Infection and immunity》2002,70(1):79-85
The characterization of Mycobacterium tuberculosis antigens inducing CD4(+) T-cell responses could critically contribute to the development of subunit vaccines for M. tuberculosis. Here we performed computational analysis by using T-cell epitope prediction software (known as TEPITOPE) to predict promiscuous HLA-DR ligands in the products of the mce genes of M. tuberculosis. The analysis of the proliferative responses of CD4(+) T cells from patients with pulmonary tuberculosis to selected peptides displaying promiscuous binding to HLA-DR in vitro led us to the identification of a peptide that induced proliferation of CD4(+) cells from 50% of the tested subjects. This study demonstrates that a systematic computational approach can be used to identify T-cell epitopes in proteins expressed by an intracellular pathogen. 相似文献
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Expression and functional activity of CXCR-4 and CCR-5 chemokine receptors in human thymocytes 总被引:4,自引:0,他引:4
Zamarchi R Allavena P Borsetti A Stievano L Tosello V Marcato N Esposito G Roni V Paganin C Bianchi G Titti F Verani P Gerosa G Amadori A 《Clinical and experimental immunology》2002,127(2):321-330
In this paper we addressed the expression of the HIV co-receptors CXCR-4 and CCR-5 in human thymocytes by phenotypic, molecular and functional approaches. Cytofluorimetric analysis disclosed that CXCR-4 was constitutively expressed by freshly isolated thymocytes (~10 000 molecules/cell in about 30% of thymocytes); the receptor was endowed with functional activity, as it mediated polarization, migration and intracellular Ca2+ increase in response to its ligand, SDF-1. On the contrary, CCR-5 expression in freshly isolated thymocytes was significantly lower (<4000 molecules/cell in less than 5% of the cells), and no functional response to CCR-5 agonists could be documented. Northern blot analysis of freshly isolated thymocytes showed high CXCR-4 mRNA levels, whereas the message for CCR-5 was barely detectable. On the other hand, a modest increase in the expression of CCR-5 was associated with in vitro thymocyte stimulation, and CCR-5 density at the cell surface attained CXCR-4 figures in most cases. None the less, no functional response to CCR-5 agonists could be documented in in vitro stimulated thymocytes. In vitro infection of thymocytes by CAT-expressing recombinant HIV bearing the envelope glycoproteins from different isolates showed that T-tropic strains, which use CXCR-4 as a co-receptor, were more efficient in infecting thymocytes than M-tropic strains, which preferentially use CCR-5. Altogether, these data indicate that expression of the major co-receptors involved in infection by M-tropic HIV strains is very poor in human thymocytes, and would suggest that thymocyte infection by M-tropic HIV strains may be a rare event in vivo. 相似文献
10.
A PCR-colorimetric microwell plate hybridization assay for detection of Mycobacterium tuberculosis and M. avium from culture samples and Ziehl-Neelsen-positive smears
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Rossi MC Gori A Zehender G Marchetti G Ferrario G De Maddalena C Catozzi L Bandera A Esposti AD Franzetti F 《Journal of clinical microbiology》2000,38(5):1772-1776
Differentiation between Mycobacterium tuberculosis and M. avium is essential for the treatment of mycobacterial infections. We have developed an easy and rapid detection assay for the diagnosis of mycobacterial diseases. This is a PCR-hybridization assay based on selective amplification of a 16S rRNA gene sequence using pan-Mycobacterium primers followed by hybridization of the amplification products to biotinylated M. tuberculosis and M. avium-specific probes. A total of 55 mycobacterial isolates were tested. For all isolates, results concordant with those of conventional identification methods were obtained. Moreover, we developed a method for extraction of DNA from Ziehl-Neelsen-positive smears which allows the recovery of intact target DNA in our PCR-hybridization assay. Our method was able to confirm all culture results for 59 Ziehl-Neelsen-positive smears from clinical specimens (35 sputum, 11 lymph node biopsy, 6 stool, 4 pus, 2 urine, and 1 pericardial fluid specimens). These data suggest that our PCR-hybridization assay, which is simple to perform and less expensive than commercial probe methods, may be suitable for the identification of M. tuberculosis and M. avium. It could become a valuable alternative approach for the diagnosis of mycobacterial infections when applied directly to DNA extracted from Ziehl-Neelsen-positive smears as well. 相似文献