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排序方式: 共有5251条查询结果,搜索用时 15 毫秒
81.
82.
Prothrombin antigen levels in symptomatic and asymptomatic carriers of the 20210A prothrombin variant 总被引:9,自引:0,他引:9
Paolo Simioni Daniela Tormene Davide Manfrin Sabrina Gavasso Sonia Luni Domenico Stocco & Antonio Girolami 《British journal of haematology》1998,103(4):1045-1050
A recently discovered variant in the prothrombin gene (20210A) has been found in approximately 5–10% of patients with venous thromboembolism. It has been shown that patients with this variant present with high levels of prothrombin in plasma and this is maintained to be the most likely mechanism by which the risk of thrombosis is increased. We have evaluated prothrombin antigen levels in 50 carriers of the 20210A allele and compared with non-carriers. 327 subjects were subdivided according to deficiency status and previous thrombosis. 30 symptomatic and 20 asymptomatic carriers had increased mean prothrombin levels as compared to symptomatic ( n = 178) or asymptomatic ( n = 99) non-carriers. The percentage of subjects with prothrombin levels above cut-off values of 1.15 u/ml or 1.30 u/ml was significantly higher in carriers of the prothrombin variant as compared to non-carriers, regardless of a previous thrombosis. However, among non-carriers the percentage of those with prothrombin levels above cut-off values was significantly higher in the group of symptomatic as compared to asymptomatic individuals. In conclusion, increased prothrombin antigen levels, as detected by a specific ELISA, were found among 50 symptomatic and asymptomatic carriers of the 20210A prothrombin variant as well as among a large group of symptomatic non-carriers. The data are in agreement with those found by using functional tests for the determination of prothrombin levels in these patients. 相似文献
83.
Steigerwalt RD Cesarone MR Belcaro G Pascarella A De Angelis M Bacci S 《The International journal of angiology》2008,17(4):193-196
BACKGROUND:
Acute nonarteritic anterior ischemic optic neuropathy (NAION) is considered to be acute ischemia of the posterior ciliary arteries. Prostaglandin E1 (PGE1), a powerful microcirculation vasodilator, has been shown to improve ocular blood flow.DESIGN:
A nonrandomized, comparative trial.METHODS:
Eight consecutive cases of NAION were treated with intravenous steroids and PGE1. Seven control cases of NAION were treated with acetylsalicylic acid and oral steroids. Fisher’s exact test was used for statistical analysis.RESULTS:
The visual acuity improved in seven cases of NAION treated with PGE1 and was unchanged in one. Of the seven control cases, four had no change in vision and three lost further visual acuity on follow-up visits.CONCLUSIONS:
Intravenous PGE1 and steroids should be considered in cases of NAION to immediately restore blood flow to the optic nerve and improve visual acuity. 相似文献84.
Kathrin Witmer Farah A. Dahalan Michael J. Delves Sabrina Yahiya Oliver J. Watson Ursula Straschil Darunee Chiwcharoen Boodtee Sornboon Sasithon Pukrittayakamee Richard D. Pearson Virginia M. Howick Mara K. N. Lawniczak Nicholas J. White Arjen M. Dondorp Lucy C. Okell Kesinee Chotivanich Andrea Ruecker Jake Baum 《Antimicrobial agents and chemotherapy》2021,65(1)
85.
Sabrina Krautbauer Kristina Eisinger Madeleine Lupke Josef Wanninger Petra Ruemmele Yvonne Hader Thomas S. Weiss Christa Buechler 《Experimental and molecular pathology》2013
Non-alcoholic fatty liver disease (NAFLD) is among the most common liver diseases. Oxidative stress is one of the pathogenic mechanisms contributing to the progression of simple fatty liver to non-alcoholic steatohepatitis (NASH). Manganese superoxide dismutase (MnSOD) is a mitochondrial antioxidative enzyme and here its expression in rodent and human NAFLD has been analyzed. MnSOD is found reduced in the liver of male mice fed a high fat diet and male ob/ob mice. Female mice fed an atherogenic diet to induce NASH have MnSOD protein levels comparable to controls. In a cohort of 30 controls, 41 patients with fatty liver and 39 NASH patients, MnSOD mRNA is significantly lower in the steatotic and NASH liver. When analyzed in both genders separately reduction of MnSOD expression is only found in males. Here, MnSOD mRNA negatively correlates with steatosis grade but not with extent of fibrosis or inflammation. MnSOD is, however, not reduced in primary human hepatocytes (PHH) treated with palmitate or oleate to increase cellular triglycerides. Lipopolysaccharide, TNF, IL-6, TGFβ and leptin which are all raised in NAFLD do not affect MnSOD in PHH. Adiponectin which attenuates oxidative stress partly by increasing MnSOD in macrophages does not induce MnSOD in PHH. In summary, current data show that hepatic MnSOD is reduced in male but not female humans and rodents with NAFLD. 相似文献
86.
Sabrina Cattaruzza Pier Andrea Nicolosi Roberto Perris 《Connective tissue research》2013,54(3-4):225-229
Proteoglycans (PGs) as a whole, or when considering their GAG chains as single entities, are emerging as key regulators of tumor progression. Expectations on using them as putative prognostic markers and potential therapeutic targets are increasing coincidentally. Due to the multitude of biological roles that they may invest and the ample spectrum of cellular processes that they may control, we still need to learn better how they regulate phenomena such as intracellular signaling, proliferation, apoptosis, motility, and drug resistance. Depending on the type, their expression pattern, and the accessibility of their molecular ligands, PGs can either promote or inhibit tumorigenesis. The structural and functional diversity of PGs coupled with their ubiquitous abundance place them at the crossroads of many critical steps within the metastatic cascade. As this phenomenon is the pivotal factor for patient survivals, particular attention should be given to the understanding of how PGs govern metastasis formation. 相似文献
87.
Maria A. Panaro Carlo I. Mitolo Angela Acquafredda Antonia Cianciulli Sabrina Lisi Chiara Porro 《Immunopharmacology and immunotoxicology》2013,35(3):475-488
Six representative CXCR4 mRNAs of fish, amphibia, birds, and mammals were selected to study the pattern of conservation/mutation of the individual nt of the coding sequences. According to an arbitrary conservation index ranging from 1 to 6, the indexes of conservation were: 5.04 for the first nt of coding triplets; 5.34 for the second nt of triplets, and 3.75 for the third nt of triplets. The average conservation index of the individual triplets was 4.71. The conservation index of the seven hydrophobic transmembrane domains was 5.60, while the cumulative conservation index of the intracytoplasmic and extracellular domains was 4.63. Separate autocorrelation and power spectral analyses of the series of conservation indexes for the first nt, the second nt and the triplets demonstrated a modest “basic” positive correlation for about the first 20 lags and accordingly some power concentration at the lower frequencies (long periods). Within the triplets, the correlation was studied between the conservation indexes of nt 1 and 2, 1 and 3, and 2 and 3. Correlations of 1 with 3 and 2 with 3 were positive, but in the range of the basic local correlation, whereas the correlation between the first and second nt was significantly higher. This correlation, together with the higher conservation of the second nt as compared to the first (two patterns also found in the formyl peptide receptors), are likely to have been established by selection processes directed towards a functional conservation or a “functional repair.” 相似文献
88.
Bucello Sebastiano Annovazzi Pietro Ragonese Paolo Altieri Marta Barcella Valeria Bergamaschi Roberto Bianchi Alessia Borriello Giovanna Buscarinu Maria Chiara Callari Graziella Capobianco Marco Capone Fioravante Cavalla Paola Cavarretta Rosella Cortese Antonio De Luca Giovanna Di Filippo Massimiliano Dattola Vincenzo Fantozzi Roberta Ferraro Elisabetta Filippi Maria Maddalena Gasperini Claudio Grimaldi Luigi Maria Edoardo Landi Doriana Re Marianna Lo Mallucci Giulia Manganotti Paolo Marfia Girolama Alessandra Mirabella Massimiliano Perini Paola Pisa Marco Realmuto Sabrina Russo Margherita Tomassini Valentina Torri-Clerici Valentina Liliana Adriana Zaffaroni Mauro Zuliani Cristina Zywicki Sofia Filippi Massimo Prosperini Luca 《Journal of neurology》2021,268(8):2922-2932
Journal of Neurology - To identify baseline factors associated with disease activity in patients with relapsing–remitting multiple sclerosis (RRMS) under teriflunomide treatment. This was an... 相似文献
89.
Richard S. Finkel Erika Finanger Krista Vandenborne H. Lee Sweeney Gihan Tennekoon Perry B. Shieh Rebecca Willcocks Glenn Walter William D. Rooney Sean C. Forbes William T. Triplett Sabrina W. Yum Maria Mancini James MacDougall Angelika Fretzen Pradeep Bista Andrew Nichols Joanne M. Donovan 《Neuromuscular disorders : NMD》2021,31(5):385-396
Chronic activation of NF-κB is a key driver of muscle degeneration and suppression of muscle regeneration in Duchenne muscular dystrophy. Edasalonexent (CAT-1004) is an orally-administered novel small molecule that covalently links two bioactive compounds (salicylic acid and docosahexaenoic acid) that inhibit NF-κB. This placebo-controlled, proof-of-concept phase 2 study with open-label extension in boys ≥4-<8 years old with any dystrophin mutation examined the effect of edasalonexent (67 or 100 mg/kg/day) compared to placebo or off-treatment control. Endpoints were safety/tolerability, change from baseline in MRI T2 relaxation time of lower leg muscles and functional assessment, as well as pharmacodynamics and biomarkers. Treatment was well-tolerated and the majority of adverse events were mild, and most commonly of the gastrointestinal system (primarily diarrhea). There were no serious adverse events in the edasalonexent groups. Edasalonexent 100 mg/kg was associated with slowing of disease progression and preservation of muscle function compared to an off-treatment control period, with decrease in levels of NF-κB-regulated genes and improvements in biomarkers of muscle health and inflammation. These results support investigating edasalonexent in future trials and have informed the design of the edasalonexent phase 3 clinical trial in boys with Duchenne. 相似文献
90.
Noudjoud Attaf Sabrina Baaklini Laurine Binet Pierre Milpied 《European journal of immunology》2021,51(11):2555-2567
Upon antigen exposure, activated B cells in antigen-draining lymphoid organs form microanatomical structures, called germinal centers (GCs), where affinity maturation occurs. Within the GC microenvironment, GC B cells undergo proliferation and B cell receptor (BCR) genes somatic hypermutation in the dark zone (DZ), and affinity-based selection in the light zone (LZ). In the current paradigm of GC dynamics, high-affinity LZ B cells may be selected by cognate T- follicular helper cells to either differentiate into plasma cells or memory B cells, or re-enter the DZ and initiate a new round of proliferation and BCR diversification, before migrating back to the LZ. Given the diversity of cell states and potential cell fates that GC B cells may adopt, the two-state DZ-LZ paradigm has been challenged by studies that explored GC B-cell heterogeneity with a variety of single-cell technologies. Here, we review studies and single-cell technologies which have allowed to refine the working model of GC B-cell cellular and molecular heterogeneity during affinity maturation. This review also covers the use of single-cell quantitative data for mathematical modeling of GC reactions, and the application of single-cell genomics to the study of GC-derived malignancies. 相似文献