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排序方式: 共有4372条查询结果,搜索用时 15 毫秒
91.
Silvia Jiménez-Morales Nora Martínez-Aguilar Roberto Gamboa-Becerra Juan Luis Jiménez-Ruíz Diana López-Ley Hong Lou Yolanda Saldaña-Alvarez Michael Dean Lorena Orozco 《Human immunology》2013
Asthma is characterized by chronic airway inflammation, which induces airway remodelling of the extracellular matrix over time. Matrix metalloproteinases (MMPs) are involved in this process, and single-nucleotide polymorphisms (SNPs) in MMP genes may influence their mRNA expression levels or abilities to bind substrates and inhibitors, thereby contributing to asthma predisposition and severity. MMP-9 is highly expressed in airways and many studies support its involvement in asthma pathogenesis; however the contribution of MMP-9 SNPs is controversial. To investigate whether MMP-9 SNPs are associated with childhood-onset asthma in Mexican patients we conducted a case-control study including 403 children with clinical asthma diagnoses and 426 healthy controls from Mexico. The cases and controls were matched by ethnicity and gender. We found that the SNPs rs2274755, rs17577, and rs3918249 were associated with asthma risk. The most significant associations were with rs2274755 (OR = 2.10, 95% CI 1.31–3.39, P = 0.001) and rs17577 (OR = 2.07, 95% CI 1.29–3.30, P = 0.001); which were in strong linkage disequilibrium. Both SNPs were also associated with atopic asthma (OR = 2.38, 95% CI 1.44–3·96, P = 0.0005). The SNP rs3918249 exhibited a female gender-dependent association with asthma (OR = 1.66, 95% CI 1.14–2.43, P = 0.007). Our results suggest that MMP-9 polymorphisms could play a role in the susceptibility to childhood-onset asthma. 相似文献
92.
Carles Ubeda Vanni Bucci Silvia Caballero Ana Djukovic Nora C. Toussaint Michele Equinda Lauren Lipuma Lilan Ling Asia Gobourne Daniel No Ying Taur Robert R. Jenq Marcel R. M. van den Brink Joao B. Xavier Eric G. Pamer 《Infection and immunity》2013,81(3):965-973
Bacteria causing infections in hospitalized patients are increasingly antibiotic resistant. Classical infection control practices are only partially effective at preventing spread of antibiotic-resistant bacteria within hospitals. Because the density of intestinal colonization by the highly antibiotic-resistant bacterium vancomycin-resistant Enterococcus (VRE) can exceed 109 organisms per gram of feces, even optimally implemented hygiene protocols often fail. Decreasing the density of intestinal colonization, therefore, represents an important approach to limit VRE transmission. We demonstrate that reintroduction of a diverse intestinal microbiota to densely VRE-colonized mice eliminates VRE from the intestinal tract. While oxygen-tolerant members of the microbiota are ineffective at eliminating VRE, administration of obligate anaerobic commensal bacteria to mice results in a billionfold reduction in the density of intestinal VRE colonization. 16S rRNA gene sequence analysis of intestinal bacterial populations isolated from mice that cleared VRE following microbiota reconstitution revealed that recolonization with a microbiota that contains Barnesiella correlates with VRE elimination. Characterization of the fecal microbiota of patients undergoing allogeneic hematopoietic stem cell transplantation demonstrated that intestinal colonization with Barnesiella confers resistance to intestinal domination and bloodstream infection with VRE. Our studies indicate that obligate anaerobic bacteria belonging to the Barnesiella genus enable clearance of intestinal VRE colonization and may provide novel approaches to prevent the spread of highly antibiotic-resistant bacteria. 相似文献
93.
94.
Thomas Klopstock MD Aleksandar Videnovic MD Almut Turid Bischoff MD Cecilia Bonnet MD Laura Cif MD Cynthia Comella MD Marta Correa-Vela MD Maria L. Escolar MD Jamie L. Fraser MD Victoria Gonzalez MD Neal Hermanowicz MD Robert Jech MD Hyder A. Jinnah MD Tomasz Kmiec MD Anthony Lang MD Maria J. Martí MD Saadet Mercimek-Andrews MD Migvis Monduy MD Graeme A.M. Nimmo MBBS Belen Perez-Dueñas MD Helle Cecilie Viekilde Pfeiffer MD Lluis Planellas MD Emmanuel Roze MD Nivedita Thakur MD Laura Tochen MD Nora Vanegas-Arroyave MD Giovanna Zorzi MD Colleen Burns PhD Feriandas Greblikas MD 《Movement disorders》2021,36(6):1342-1352
95.
Nora I. Schneider Wolfgang Plieschnegger Michael Geppert Bernd Wigginghaus Gabriele M. Höss Andreas Eherer Eva-Maria Wolf Peter Rehak Michael Vieth Cord Langner 《Virchows Archiv : an international journal of pathology》2013,463(5):643-650
Pancreatic acinar cells are a well-recognized finding at the gastroesophageal junction, but their histogenesis and biological significance are unclear. From the prospective Central European multicenter histoGERD trial, we recruited 1,071 individuals undergoing gastroscopy for various non-selected reasons. Biopsy material was systematically sampled from the gastroesophageal junction and from the stomach. The study aimed to assess the prevalence of pancreatic acinar cells and to relate their presence to various histologic and clinical features. Overall, pancreatic acinar cells were observed in 184 (17.2 %) participants. Individuals diagnosed with pancreatic acinar cells were slightly younger than those without (median 50 vs. 53 years; p?=?0.009). There was no association with patients’ symptoms and/or complaints or with an endoscopic diagnosis of esophagitis or Barrett’s esophagus. Regarding histology, pancreatic acinar cells were not associated with features of the squamous epithelium indicating reflux disease, such as basal cell hyperplasia, papillary elongation, dilation of intercellular spaces, and inflammatory cell number, but were associated with the presence of cardiac mucosa (p?<?0.001), oxyntocardiac mucosa (p?<?0.001), and intestinal metaplasia (p?=?0.038), respectively. No association with Helicobacter pylori infection or diagnosis of gastritis was noted. In conclusion, pancreatic acinar cells are a common finding at the gastroesophageal junction, and no association with either reflux disease (histologically or endoscopically) or diagnosis of gastritis was observed. These data suggest a congenital rather than an acquired (metaplastic) origin of pancreatic acinar cells at the gastroesophageal junction. This questions the term “pancreatic acinar metaplasia” which is currently widely used for their diagnosis. 相似文献
96.
Nathalia Paula Scioscia Pablo Martín Beldomenico Romina Sandra Petrigh Nora Pierangeli Guillermo María Denegri 《Parasitology research》2013,112(10):3607-3613
In Argentina, hydatid disease caused by Echinococcus granulosus is widespread. The south of Buenos Aires province, Argentina, is one of the three regions where hydatidosis is endemic. Although domestic dogs and sheep are considered to be the main hosts for E. granulosus, the potential role of wildlife in the local transmission of E. granulosus has not been investigated. The aim of this study was to estimate the hydatidosis/echinococcosis prevalence in European hare (Lepus europaeus) and Pampas fox (Lycalopex gymnocercus), two abundant species with a strong predator–prey relationship in rural areas of Buenos Aires province using different diagnostic tests. A total of 61 fox intestines were examined, finding that 52 (85.2 %) harbored at least one helminth species. However, no adult or immature form of Echinococcus sp. was found in the intestinal contents. Coproparasitological analysis and Copro–ELISA followed by Copro–PCR were used as supplementary diagnostic tests. Only one (1.7 %) of 59 fecal samples was positive to Taeniidae eggs by coproparasitological analysis, but this same sample was negative by the Copro–ELISA test. The analysis by Copro–ELISA showed 6 of 57 (10.6 %) positive samples, but the Copro–PCR tests carried out on these samples were negative to E. granulosus. A total of 6,808 lungs, 3,576 livers, and 3,542 hearts of hunted hares were examined and palpated, but no structure resembling hydatid cysts were detected. Our results suggest that hares and Pampas foxes are not currently important wild reservoirs of E. granulosus in the studied area. 相似文献
97.
Castano-Jaramillo Lina M. Yamazaki-Nakashimada Marco Antonio O’Farrill-Romanillos Patricia M. Muzquiz Zermeño David Scheffler Mendoza Selma C. Venegas Montoya Edna García Campos Jorge Alberto Sánchez-Sánchez Luz María Gámez González Luisa B. Ramírez López Jesús Moisés Bustamante Ogando Juan Carlos Vásquez-Echeverri Estefanía Medina Torres Edgar Alejandro Lopez-Herrera Gabriela Blancas Galicia Lizbeth Berrón Ruiz Laura Staines-Boone Aidé Tamara Espinosa-Padilla Sara Elva Segura Mendez Nora Hilda Lugo Reyes Saul O. 《Journal of clinical immunology》2021,41(7):1463-1478
Journal of Clinical Immunology - Patients with inborn errors of immunity (IEI) have a compromised or inappropriate immune response. Although they might be considered a high-risk group for severe... 相似文献
98.
99.
Pamidronate is superior to ibandronate in decreasing bone resorption,interleukin-6 and beta 2-microglobulin in multiple myeloma 总被引:1,自引:0,他引:1
Terpos E Viniou N de la Fuente J Meletis J Voskaridou E Karkantaris C Vaiopoulos G Palermos J Yataganas X Goldman JM Rahemtulla A 《European journal of haematology》2003,70(1):34-42
OBJECTIVES: Bisphosphonates have been found to reduce skeletal events in patients with multiple myeloma (MM). This is the first randomised trial to compare the efficacy of pamidronate and ibandronate, a third-generation aminobisphosphonate, in bone turnover and disease activity in MM patients. METHODS: Patients with MM, stage II or III, were randomly assigned to receive either pamidronate 90 mg (group I: 23 patients) or ibandronate 4 mg (group II: 21 patients) as a monthly intravenous infusion in addition to conventional chemotherapy. Skeletal events, such as pathologic fractures, hypercalcaemia, and bone radiotherapy were analysed. Bone resorption markers [N-terminal cross-linking telopeptide of type-I collagen (NTX) and tartrate-resistant acid phosphatase type 5b (TRACP-5b)], bone formation markers (bone alkaline phosphatase and osteocalcin), markers of disease activity (paraprotein, CRP, beta 2-microglobulin), and interleukin-6 (IL-6) were also studied. RESULTS: In both groups, the combination of chemotherapy with either pamidronate or ibandronate produced a reduction in bone resorption and tumour burden as measured by NTX, IL-6, paraprotein, CRP, and beta 2-microglobulin from the second month of treatment, having no effect on bone formation. TRACP-5b also had a significant reduction in the pamidronate group from the second month of treatment and in the ibandronate group from the sixth month. However, there was a greater reduction of NTX, IL-6, and beta 2-microglobulin in group I than in group II, starting at the second month of treatment (P = 0.002, 0.001, and 0.004, respectively) and of TRACP-5b, starting at the fourth month (P = 0.014), that being continued throughout the 10-month follow-up of this study. There was no difference in skeletal events during this period. A significant correlation was observed between changes of NTX and changes of TRACP-5b, IL-6, and beta 2-microglobulin from the second month for patients of both groups. CONCLUSIONS: These results suggest that a monthly dose of 90 mg of pamidronate is more effective than 4 mg of ibandronate in reducing osteoclast activity, bone resorption, IL-6, and possibly tumour burden in MM. TRACP-5b has also proved to be a useful new marker for monitoring bisphosphonates treatment in MM. 相似文献
100.
Comparative impacts of two major hurricane seasons on the Neuse River and western Pamlico Sound ecosystems 总被引:1,自引:0,他引:1
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Burkholder J Eggleston D Glasgow H Brownie C Reed R Janowitz G Posey M Melia G Kinder C Corbett R Toms D Alphin T Deamer N Springer J 《Proceedings of the National Academy of Sciences of the United States of America》2004,101(25):9291-9296
Ecosystem-level impacts of two hurricane seasons were compared several years after the storms in the largest lagoonal estuary in the U.S., the Albemarle-Pamlico Estuarine System. A segmented linear regression flow model was developed to compare mass-water transport and nutrient loadings to a major artery, the Neuse River Estuary (NRE), and to estimate mean annual versus storm-related volume delivery to the NRE and Pamlico Sound. Significantly less water volume was delivered by Hurricane Fran (1996), but massive fish kills occurred in association with severe dissolved oxygen deficits and high contaminant loadings (total nitrogen, total phosphorus, suspended solids, and fecal bacteria). The high water volume of the second hurricane season (Hurricanes Dennis, Floyd, and Irene in 1999) delivered generally comparable but more dilute contaminant loads, and no major fish kills were reported. There were no discernable long-term adverse impacts on water quality. Populations of undesirable organisms, such as toxic dinoflagellates, were displaced down-estuary to habitats less conducive for growth. The response of fisheries was species-dependent: there was no apparent impact of the hurricanes on commercial landings of bivalve molluscs or shrimp. In contrast, interacting effects of hurricane floodwaters in 1999 and intensive fishing pressure led to striking reductions in blue crabs. Overall, the data support the premise that, in shallow estuaries frequently disturbed by hurricanes, there can be relatively rapid recovery in water quality and biota, and benefit from the scouring activity of these storms. 相似文献