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排序方式: 共有10000条查询结果,搜索用时 15 毫秒
991.
Nahum Méndez‐Sánchez Daniel Zamora‐Valdés José A. Flores‐Rangel Julio A. Pérez‐Sosa Francisco Vásquez‐Fernández Jezer I. Lezama‐Mora Genaro Vázquez‐Elizondo Guadalupe Ponciano‐Rodríguez Martha H. Ramos Misael Uribe 《Liver international》2008,28(3):402-406
Background/Aims: Gallstone disease (GD) and cardiovascular disease (CD) are common diseases worldwide with considerable economical impact and they are strongly associated. Carotid atherosclerosis is an excellent marker of risk for CD like stroke and myocardial infarction. The aim of this study was to assess the association between gallstones and carotid atherosclerosis. Methods: A cross‐sectional study was conducted. We evaluated subjects with ultrasonographical evidence of GD and asymptomatic subjects without such evidence. Anthropometric, clinical and biochemical variables were collected. The Metabolic syndrome was evaluated using adult treatment panel III criteria. Carotid artery intima–media thickness (CIMT) was determined by a standard ultrasound protocol. Insulin‐like growth factor‐1 (IGF‐1) serum levels were measured in all subjects. Results: We studied 191 subjects: 62 subjects with GD (53.2% males) and 129 asymptomatic subjects without GD (65.9% males). Subjects with GD exhibited a higher body mass index, body fat percent, insulin serum levels and CIMT (P<0.05 for all). The prevalence of GD was higher in subjects with a CIMT>0.75 independently of other factors [odds ratio (OR) 2.12, 95% confidence interval (CI) 1.04–4.34; P=0.039], and for every 0.1 mm increase in CIMT the independent probability to be a case of GD increased by a factor of 1.25 (95% CI 1.02–1.53; P=0.027). IGF‐1 levels did not differ among groups. Conclusions: Subjects with GD exhibit greater carotid atherosclerosis, and therefore have a higher risk for stroke and myocardial infarction. 相似文献
992.
993.
Claude Perreault Marc Giasson Martin Gyger Robert Belanger Michele David Yvette Bonny Jacques Boileau Raymond Barcelo Jean Pierre Moquin 《Annals of hematology》1985,51(3):137-142
Summary In order to study the posttransplant evolution of serum immunoglobulin levels, we measured serum IgG, IgA and IgM levels in 50 recipients of allogeneic bone marrow before transplantation and at different intervals thereafter (days 39, 120, 365 and 730). IgG and IgM levels were depressed for 1 year and IgA levels for 2 years posttransplant. Immunoglobulin deficiency was more severe and prolonged in patients with graft versus-host-disease. Hypogammaglobulinemia may contribute to the frequent infections observed in these patients, especially those with chronic graft-versus-host disease. 相似文献
994.
Mathieu E. Rebeaud Saurav Mallik Pierre Goloubinoff Dan S. Tawfik 《Proceedings of the National Academy of Sciences of the United States of America》2021,118(21)
Across the Tree of Life (ToL), the complexity of proteomes varies widely. Our systematic analysis depicts that from the simplest archaea to mammals, the total number of proteins per proteome expanded ∼200-fold. Individual proteins also became larger, and multidomain proteins expanded ∼50-fold. Apart from duplication and divergence of existing proteins, completely new proteins were born. Along the ToL, the number of different folds expanded ∼5-fold and fold combinations ∼20-fold. Proteins prone to misfolding and aggregation, such as repeat and beta-rich proteins, proliferated ∼600-fold and, accordingly, proteins predicted as aggregation-prone became 6-fold more frequent in mammalian compared with bacterial proteomes. To control the quality of these expanding proteomes, core chaperones, ranging from heat shock proteins 20 (HSP20s) that prevent aggregation to HSP60, HSP70, HSP90, and HSP100 acting as adenosine triphosphate (ATP)-fueled unfolding and refolding machines, also evolved. However, these core chaperones were already available in prokaryotes, and they comprise ∼0.3% of all genes from archaea to mammals. This challenge—roughly the same number of core chaperones supporting a massive expansion of proteomes—was met by 1) elevation of messenger RNA (mRNA) and protein abundances of the ancient generalist core chaperones in the cell, and 2) continuous emergence of new substrate-binding and nucleotide-exchange factor cochaperones that function cooperatively with core chaperones as a network.All cellular life is thought to have stemmed from the last universal common ancestor (LUCA) (1, 2), that emerged more than 3.6 billion y ago. Two major kingdoms of life diverged from LUCA: bacteria and archaea, which about 2 billion y later merged into the eukaryotes (3). Since the beginning of biological evolution, life’s volume has increased on a grand scale: The average size of individual cells has increased ∼100-fold from prokaryotes to eukaryotes (4), the number of cell types has increased ∼200-fold from unicellular eukaryotes to humans (5), and average body size has increased ∼5,000-fold from the simplest sponges to blue whales (6).This expansion in organismal complexity and variability was accompanied by an expansion in life’s molecular workforce, proteomes in particular, which in turn presented a challenge of reaching and maintaining properly folded and functional proteomes. Most proteins must fold to their native structure in order to function, and their folding is largely imprinted in their primary amino acid sequence (7–9). However, many proteins, and especially large multidomain polypeptides, or certain protein types such as all-beta or repeat proteins, tend to misfold and aggregate into inactive species that may also be toxic (10). Life met this challenge by evolving molecular chaperones that can minimize protein misfolding and aggregation, even under stressful out-of-equilibrium conditions favoring aggregation (11, 12). Chaperones can be broadly divided into core and cochaperones. Core chaperones can function on their own, and include ATPases heat shock protein 60 (HSP60), HSP70, HSP100, and HSP90 and the adenosine triphosphate (ATP)-independent HSP20. The basal protein holding, unfolding, and refolding activities of the core chaperones are facilitated and modulated by a range of cochaperones such as J-domain proteins (13–15).Starting from LUCA, as proteomes expanded, so did the core chaperones and their respective cochaperones. Indeed, chaperones have been shown to facilitate the acquisition of destabilizing mutations and thereby accelerate protein evolution (16–18). However, the coexpansion of proteomes and of chaperones, underscoring a critical balance between evolutionary innovation and foldability, remains largely unexplored. We thus embarked on a systematic bioinformatics analysis that explores the evolution of both proteomes and chaperones, and of both core and their auxiliary cochaperones, along the Tree of Life. 相似文献
995.
996.
Value of preoperative investigations in diagnosing prosthetic joint infection: retrospective cohort study and literature review 总被引:2,自引:0,他引:2
Bernard L Lübbeke A Stern R Bru JP Feron JM Peyramond D Denormandie P Arvieux C Chirouze C Perronne C Hoffmeyer P;Groupe D'Etude Sur L'Ostéite 《Scandinavian journal of infectious diseases》2004,36(6-7):410-416
The diagnosis of a prosthetic joint infection is difficult, but crucial for appropriate treatment. Scintigraphy with specific markers for infection (labelled white cells or immunoglobulin-G) has been reported as a more reliable diagnostic tool than clinical assessment (fever, fistula), laboratory studies (polynuclear neutrophil count, erythrocyte rate sedimentation, and C-reactive protein), and preoperative aspiration. In the first part of this study, we retrospectively reviewed 230 patients admitted with a suspected prosthetic joint infection, and examined the validity of the different diagnostic tools for the group as a whole and for subgroups according to the Coventry classification. In the second part, we reviewed 35 articles about preoperative evaluation of infection in prosthetic joints and compared them to our findings. Our study indicates that C-reactive protein and joint aspiration are the most useful tools to diagnose prosthetic joint infection even in situations of chronic infection (Coventry type II). 相似文献
997.
998.
Leontiou CA Gueorguiev M van der Spuy J Quinton R Lolli F Hassan S Chahal HS Igreja SC Jordan S Rowe J Stolbrink M Christian HC Wray J Bishop-Bailey D Berney DM Wass JA Popovic V Ribeiro-Oliveira A Gadelha MR Monson JP Akker SA Davis JR Clayton RN Yoshimoto K Iwata T Matsuno A Eguchi K Musat M Flanagan D Peters G Bolger GB Chapple JP Frohman LA Grossman AB Korbonits M 《The Journal of clinical endocrinology and metabolism》2008,93(6):2390-2401
999.
Rabot S Szylit O Nugon-Baudon L Meslin JC Vaissade P Popot F Viso M 《Digestive diseases and sciences》2000,45(9):1687-1695
The purpose of this work was to assess the influence of microgravity on several endogenous and microbial parameters of digestive physiology. On the occasion of two Spacelab Life Sciences missions, SLS-1 (a 9-day space flight) and SLS-2 (a 14-day space flight), Sprague-Dawley rats flown aboard the US space shuttle were compared to age-matched ground-based controls. In both flights, exposure to microgravity modified cecal fermentation: concentration and profile of short-chain fatty acids were altered, whereas urea and ammonia remained unchanged. Only in SLS-1 was there an induction of intestinal glutathione-S-transferase. Additional analyses in SLS-2 showed a decrease of hepatic CYP450 and of colonic goblet cells containing neutral mucin. After a postflight recovery period equal to the mission length, only modifications of the hepatic and intestinal xenobiotic metabolizing enzymes still persisted. These findings should help to predict the alterations of digestive physiology and detoxification potential likely to occur in astronauts. Their possible influence on health is discussed. 相似文献
1000.
Matthew P. Cheng Pierre René Alexandre P. Cheng Todd C. Lee 《The American journal of medicine》2016,129(12):1331-1333