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排序方式: 共有9102条查询结果,搜索用时 15 毫秒
41.
Gerda T. Noordhoek Sitha A. Scheltinga Paul Caesar Leo M. Schouls John E. Degener 《Clinical microbiology and infection》1997,3(3):356-364
Objective: To apply PCR-based DNA fingerprinting in a clinical microbiology laboratory to investigate nosocomial infections with Staphylococcus haemolyticus.
Method: DNA fingerprints were generated by PCR on 99 S. haemolyticus isolates using different primer combinations based on ERIC, REP or arbitrarily chosen simple repeat sequences.
Results: Primer combinations REP1+(GTC)6 and ERIC1+ERIC2 had sufficient discrimatory power and were chosen to analyze the clinical isolates. DNA fingerprint patterns from strains isolated from the patients nursed in the same hospital ward in the period 1991–94 were approximately 90% similar to each other. One staff member, sampled in 1991, carried a strain with a similar fingerprint.
Conclusions: PCR based DNA fingerprinting is a suitable method to perform in a clinical laboratory. An S. haemolyticus strain appeared to be endemic in the hospital ward and had most probably been transmitted from patient to patient. S. haemolyticus may carry glycopeptide resistance and needs attention as a causative agent of nosocomial infections. 相似文献
Method: DNA fingerprints were generated by PCR on 99 S. haemolyticus isolates using different primer combinations based on ERIC, REP or arbitrarily chosen simple repeat sequences.
Results: Primer combinations REP1+(GTC)
Conclusions: PCR based DNA fingerprinting is a suitable method to perform in a clinical laboratory. An S. haemolyticus strain appeared to be endemic in the hospital ward and had most probably been transmitted from patient to patient. S. haemolyticus may carry glycopeptide resistance and needs attention as a causative agent of nosocomial infections. 相似文献
42.
Two techniques for measuring palmar sweating were tested for their sensitivity to a standard anticholinergic agent. The finger sweat-print and palmar sweatweight methods were compared in a double-blind, crossover study by determining their relative sensitivity in detecting the antisweating effects of 0.5 mg of atropine sulfate. The sweat-print method was significantly superior in detecting drug-induced sweat reduction and hypothesized sex differences. 相似文献
43.
Identification of two homologous antigenic peptides derived from L1 HPV-16 and 18 proteins specific for the HLA-B*3901 allele 总被引:1,自引:0,他引:1
Monroy-García A Weiss-Steider B Hernández-Montes J Ortiz-Navarrete VF Bañuelos-Pánuco A Acosta-Araujo A Díaz-Quiñónez A López-Graniel CM Herbert G Granados J de Leo C Silva-López RM Mora-García ML 《Archives of virology》2002,147(10):1933-1942
Summary. In this work we present evidence that the homologous peptides IHSMNSTIL and IHSMNSSIL derived from L1 HPV-16 and 18 proteins
respectively, and with high specificity for the allele HLA-B*3901, according with an algorithm prediction program, induced T cell stimulation in patients with advanced cervical cancer
positive for HPV-16 or 18 infection and for the HLA-B*3901 allele. Interestingly, T lymphocytes derived from a patient with HPV-18 infection and stimulated with the peptide IHSMNSTIL
were capable to kill a cervical cancer cell line named Rova, derived from the tumor of the same patient. In addition, the
cytotoxic activity was strongly increased when this cell line was previously treated with hrIFN-γ. These results suggest that
the CTL immune response to L1 HPV-16 and 18 protein derived epitopes is maintained in patients with advanced cervical cancer
within specific alleles, and opens the possibility that homologous epitopes may be used in the generation of prophylactic
vaccines for cervical tumors bearing different HPV-types.
Received March 4, 2002; accepted May 20, 2002 相似文献
44.
Transformation of the cultivated mushroom Agaricus bisporus (Lange) using T-DNA from Agrobacterium tumefaciens 总被引:4,自引:0,他引:4
Agrobacterium tumefaciens is known to transfer parts of its tumor-inducing plasmid, the T-DNA, to plants, yeasts and filamentous fungi. We have used
this system to transform germinating basidiospores and vegetative mycelium of a commercial strain of the cultivated basidiomycete
Agaricus bisporus. Analysis of transformants shows that the T-DNA integrates at random sites into the host genome and that the selection marker
is stable during mitosis and meiosis. The Agrobacterium system allows the transformation of both homokaryons and heterokaryons of A. bisporus. Also, both karyotypes of an heterokaryon can be transformed simultaneously. Furthermore, this is the first report on the
transformation of vegetative mycelium of a commercial strain of A. bisporus.
Received: 6 June 2000 / Accepted: 10 October 2000 相似文献
45.
Differences in assembly or stability of complex I and other mitochondrial OXPHOS complexes in inherited complex I deficiency 总被引:9,自引:0,他引:9
Ugalde C Janssen RJ van den Heuvel LP Smeitink JA Nijtmans LG 《Human molecular genetics》2004,13(6):659-667
NADH-ubiquinone oxidoreductase (complex I) deficiency is amongst the most encountered defects of the mitochondrial oxidative phosphorylation (OXPHOS) system and is associated with a wide variety of clinical signs and symptoms. Mutations in complex I nuclear structural genes are the most common cause of isolated complex I enzyme deficiencies. The cell biological consequences of such mutations are poorly understood. In this paper we have used blue native electrophoresis in order to study how different nuclear mutations affect the integrity of mitochondrial OXPHOS complexes in fibroblasts from 15 complex I-deficient patients. Our results show an important decrease in the levels of intact complex I in patients harboring mutations in nuclear-encoded complex I subunits, indicating that complex I assembly and/or stability is compromised. Different patterns of low molecular weight subcomplexes are present in these patients, suggesting that the formation of the peripheral arm is affected at an early assembly stage. Mutations in complex I genes can also affect the stability of other mitochondrial complexes, with a specific decrease of fully-assembled complex III in patients with mutations in NDUFS2 and NDUFS4. We have extended this analysis to patients with an isolated complex I deficiency in which no mutations in structural subunits have been found. In this group, we can discriminate between complex I assembly and catalytic defects attending to the fact whether there is a correlation between assembly/activity levels or not. This will help us to point more selectively to candidate genes for pathogenic mutations that could lead to an isolated complex I defect. 相似文献
46.
Immunohistowax processing, a new fixation and embedding method for light microscopy, which preserves antigen immunoreactivity and morphological structures: visualisation of dendritic cells in peripheral organs 下载免费PDF全文
Pajak B De Smedt T Moulin V De Trez C Maldonado-López R Vansanten G Briend E Urbain J Leo O Moser M 《Journal of clinical pathology》2000,53(7):518-524
AIMS: To describe a new fixation and embedding method for tissue samples, immunohistowax processing, which preserves both morphology and antigen immunoreactivity, and to use this technique to investigate the role of dendritic cells in the immune response in peripheral tissues. METHODS: This technique was used to stain a population of specialised antigen presenting cells (dendritic cells) that have the unique capacity to sensitise naive T cells, and therefore to induce primary immune responses. The numbers of dendritic cells in peripheral organs of mice either untreated or injected with live Escherichia coli were compared. RESULTS: Numbers of dendritic cells were greatly decreased in heart, kidney, and intestine after the inoculation of bacteria. The numbers of dendritic cells in the lung did not seem to be affected by the injection of E coli. However, staining of lung sections revealed that some monocyte like cells acquired morphological and phenotypic features of dendritic cells, and migrated into blood vessles. CONCLUSIONS: These observations suggest that the injection of bacteria induces the activation of dendritic cells in peripheral organs, where they play the role of sentinels, and/or their movement into lymphoid organs, where T cell priming is likely to occur. 相似文献
47.
Emigration of selected subsets of {gamma}{delta}+ T cells from the adult murine thymus 总被引:1,自引:0,他引:1
Kelly Katherine A.; Pearse Martin; Lefrancois Leo; Scollay Roland 《International immunology》1993,5(4):331-335
Cells bearing the form of the TCR make up only 1–3% ofT cells in the adult murine thymus and peripheral lymphold organs.Evidence from studies of nude mice suggests that the developmentof at least some T cells is thymus dependent; however, untilnow it has not been directly demonstrated that cells are exportedfrom the thymus. In this paper we have used the technique oflabelling thymocytes in vivo with FITC, followed by flow cytometrlcanalysis to trace cells emigrating from the thymus to the spleen.Using this approach we have been able to demonstrate for thefirst time that T cells are exported from the adult murinethymus to the spleen. We also demonstrate that the cells emigratingto the spleen are a selected subset of thymocytes being heatstable antigen positive, Thy-1+, and expressing low levels ofCD44 (Pgp-1). In addition, investigation of TCR V; gene usageamong adult + thymocytes, recent emigrants, and spleen cells,indicated a selective emigration of cells expressing certainVgenes. 相似文献
48.
Three patients are described who demonstrate the "target-sign" of optic nerve atrophy on CT scanning. This sign is produced by the centrally located atrophic optic nerve surrounded by a patulous perioptic subarachnoid space. An explanation for this phenomenon is proposed. 相似文献
49.
Leo Andrew Benedict Joseph A. Sujka Justin A. Sobrino Hanna Alemayehu Pablo Aguayo Richard Hendrickson Shawn D. St. Peter Tolulope A. Oyetunji 《Journal of pediatric surgery》2021,56(4):663-667
PurposePrevious reports in the literature demonstrate racial and ethnic disparities for children diagnosed with acute appendicitis, with minorities experiencing worse outcomes. At our institution, we have developed an evidence based patient driven protocol for children following laparoscopic appendectomy. However, the influence of such protocol on mitigating racial and ethnic disparities in outcomes remains unknown. The purpose of our study is to assess the impact of our protocol by evaluating the influence of race and ethnicity on surgical outcomes among children treated for acute appendicitis.Material and methodsA retrospective review of prospectively collected data was conducted. Children undergoing a laparoscopic appendectomy at our freestanding children's hospital between December 2015 and July 2017 were included. Demographic data, post-operative length of stay, same day discharge rates and hospital readmission rates were abstracted from patient medical records. Patients were classified by their race and ethnic background. Comparative analysis was performed in STATA with a p value < .05 determined as significant.ResultsA total of 786 children were included, with the majority being either White (70%, n = 547), Black (8%, n = 62) or Hispanic (17%, n = 133); 569 patients (72%) were found to have non-perforated appendicitis. There was no statistically significant difference in the rates of same day discharge among White, Black or Hispanic children respectively (88% vs. 77% vs. 86%, p = .126). Of the 217 children with perforated appendicitis, Hispanic children had increased rates of perforation (41%, n = 55) compared to White and Black children respectively (23%, n = 128 and 29%, n = 18, p = .001). However, average post-operative length of stay were similar among White, Black and Hispanic children (96 h vs. 95 h vs. 98 h, p = .015). On multivariate analysis, the only significant risk factor for an elevated post-operative length of stay was the presence of a perforation.ConclusionOur evidence based patient driven protocol effectively mitigates racial and ethnic disparities found in children with acute appendicitis. Further prospective investigation into the role of such patient-driven protocols to mitigate healthcare disparities is warranted.Levels of EvidenceTherapeutic study; Level 3. 相似文献
50.
Fausto Biancari Giovanni Mariscalco Magnus Dalén Nicla Settembre Henryk Welp Andrea Perrotti Karsten Wiebe Enrico Leo Antonio Loforte Sidney Chocron Davide Pacini Tatu Juvonen L. Mikael Broman Dario Di Perna Hakeem Yusuff Chris Harvey Nicolas Mongardon Juan P. Maureira Antonio Fiore 《Journal of cardiothoracic and vascular anesthesia》2021,35(7):1999-2006