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排序方式: 共有680条查询结果,搜索用时 62 毫秒
61.
Cristina Granja Cláudia Dias Altamiro Costa-Pereira António Sarmento 《Critical care (London, England)》2003,8(2):R91
Introduction
The objective of the present study was to compare the health-related quality of life (HR-QoL) of survivors from severe sepsis and septic shock with HR-QoL in others who survived critical illness not involving sepsis. 相似文献62.
Dartois V Sanchez-Quesada J Cabezas E Chi E Dubbelde C Dunn C Granja J Gritzen C Weinberger D Ghadiri MR Parr TR 《Antimicrobial agents and chemotherapy》2005,49(8):3302-3310
Cyclic peptides with an even number of alternating d,l-alpha-amino acid residues are known to self-assemble into organic nanotubes. Such peptides previously have been shown to be stable upon protease treatment, membrane active, and bactericidal and to exert antimicrobial activity against Staphylococcus aureus and other gram-positive bacteria. The present report describes the in vitro and in vivo pharmacology of selected members of this cyclic peptide family. The intravenous (i.v.) efficacy of six compounds with MICs of less than 12 microg/ml was tested in peritonitis and neutropenic-mouse thigh infection models. Four of the six peptides were efficacious in vivo, with 50% effective doses in the peritonitis model ranging between 4.0 and 6.7 mg/kg against methicillin-sensitive S. aureus (MSSA). In the thigh infection model, the four peptides reduced the bacterial load 2.1 to 3.0 log units following administration of an 8-mg/kg i.v. dose. Activity against methicillin-resistant S. aureus was similar to MSSA. The murine pharmacokinetic profile of each compound was determined following i.v. bolus injection. Interestingly, those compounds with poor efficacy in vivo displayed a significantly lower maximum concentration of the drug in serum and a higher volume of distribution at steady state than compounds with good therapeutic properties. S. aureus was unable to easily develop spontaneous resistance upon prolonged exposure to the peptides at sublethal concentrations, in agreement with the proposed interaction with multiple components of the bacterial membrane canopy. Although additional structure-activity relationship studies are required to improve the therapeutic window of this class of antimicrobial peptides, our results suggest that these amphipathic cyclic d,l-alpha-peptides have potential for systemic administration and treatment of otherwise antibiotic-resistant infections. 相似文献
63.
64.
Díaz Rodríguez C Granja E Vázquez Martul E Sacristán F Moreno Fernández A González Rivero C del Río Romero D Trinidad JC 《Nefrología : publicación oficial de la Sociedad Espa?ola Nefrologia》2004,24(4):368-371
We report the case of a 37 year old man who suffered from Crohn's Disease (CD), and was receiving treatment with mesalazine (5-ASA). Nine years after the diagnosis, because of detecting a slight proteinuria, a renal biopsy is made, being the anatomo-pathologic result compatible with membranous glomerulonephritis (MGN). Checking previous literature we have only found two cases reported of MGN in coincidence with Inflammatory Bowel Disease (IBD), one in association with Ulcerative Colitis and the other with Crohn's Disease in a 12 years old boy. This is, therefore, the second case presenting MGN associated with CD and the first in an adult patient. 相似文献
65.
Cell-based therapies offer an attractive approach for revascularization and regeneration of tissues. However, and despite the pressing clinical needs for effective revascularization strategies, the successful immobilization of viable vascular cells within 3D matrices has been difficult to achieve. In this paper the in?vitro potential of a natural, injectable RGD-alginate hydrogel as an in situ forming matrix to deliver endothelial cells was evaluated. Several techniques were employed to investigate how these microenvironments could influence the behavior of vascular cells, namely their ability to promote the outward migration of viable, proliferative cells, retaining the ability to form a 3D arrangement. Cells within RGD-grafted alginate hydrogel were able to proliferate and maintained 80% of viability for at least 48?h post-immobilization. Additionally, entrapped cells created a 3D organization into cellular networks and, when put in contact with matrigel, cells migrated out of the RGD-matrix. Overall, the obtained results support the idea that the RGD peptides conjugated to alginate provide a 3D environment for endothelial cells adhesion, survival, migration and organization. 相似文献
66.
Angela AG van Tilborg Chris H Bangma Ellen C Zwarthoff 《International journal of urology》2009,16(1):23-30
Early detection of bladder cancer and its recurrences is essential for improved prognosis and long-term survival. The detection and follow-up of these patients is currently based on cystoscopy, which is expensive and invasive, and, in most cases, cytology, which is non-invasive but not very sensitive. During recent years, many urine-based tests have been developed and tested in different patient populations. In this review we discuss new developments for biomarkers in bladder cancer that have potential use in surveillance and screening. In almost all publications authors compare sensitivity of the test with a concomitantly executed cystoscopy, for example, determine cross-sectional sensitivity. However, it has also been shown that false positive test results may be followed by a positive cystoscopy in the near future, showing that cystoscopy itself does not provide 100% sensitivity. This suggests that for a proper evaluation of urine-based tests, longitudinal studies should be carried out and the results communicated to the urologist. 相似文献
67.
The action of the complement system on pigmented and hypopigmented mycelia of the fungus Fonsecaea pedrosoi, the major aetiological pathogen of the chromoblastomycosis is herein discussed. Fungi were grown in medium Czapeck-Dox at 37°C, for 14 days, without shaking to obtain pigmented mycelium. To obtain hypopigmented mycelium, the fungus was grown at the same conditions, but in the dark and with low oxygenation. Activation was measured by complement consumption and enzyme-linked immunosorbent assay. We also observed by immunofluorescence the deposition of C3, C4 fragments and C9 on the surface of the different forms studied. The results indicate that both forms were able to activate the complement system mainly by the alternative pathway. Pigmented mycelia had the highest consumption results, indicating that the pigment, melanin, may have influence in activation. 相似文献
68.
AG Stewart 《British journal of pharmacology》2009,158(4):933-935
The active resolution of inflammation is recognized as offering new opportunities to generate novel anti-inflammatory agents. The emerging appreciation of the importance of active resolution in regulation of inflammation also creates an imperative to examine developing and existing agents for their potential to influence these pathways. This themed issue of the British Journal of Pharmacology contains papers that discuss the roles of annexin-1, lipoxins and related lipid products of fish oils as well as other mechanisms involved in active resolution and their receptor targets.This article is part of a themed issue on Mediators and Receptors in the Resolution of Inflammation. To view this issue visit http://www3.interscience.wiley.com/journal/121548564/issueyear?year=2009 相似文献
69.
Background and purpose:
In the mammalian brain, histaminergic neurotransmission is mediated by the postsynaptic histamine H1 and H2 receptors and the presynaptic H3 autoreceptor, which also acts as a heteroreceptor. The H1 receptor has been implicated in spatial learning and memory formation. However, pharmacological and lesion studies have revealed conflicting results. To examine the involvement of histamine H1 receptor in spatial reference and working memory formation, H1 receptor knockout mice (KO) were tested in the eight-arm radial maze. Previously, we found that the H1 receptor-KO mice showed reduced emotionality when confronted with spatial novelty. As it is known that emotions can have an impact on spatial learning and memory performance, we also evaluated H1 receptor-KO mice in terms of emotional behaviour in the light–dark box.Experimental approach:
Mice lacking the H1 receptor and wild-type mice (WT) were tested for spatial reference and working memory in an eight-arm radial maze with three arms baited and one trial per day. Emotional behaviour was measured using the light–dark test.Key results:
The H1 receptor-KO mice showed impaired spatial reference and working memory in the radial maze task. No significant differences between H1 receptor-KO and WT mice were observed in the light–dark test.Conclusions and implications:
The spatial memory deficits of the H1 receptor-KO mice might be due to the reported changes in cholinergic neurochemical parameters in the frontal cortex and the CA1 subregion of the hippocampus, to impaired synaptic plasticity in the hippocampus, and/or to a dysfunctional brain reward/reinforcement system. 相似文献70.
Patty H Spruit Sabine Siesling Marloes AG Elferink Ernest JA Vonk Carel JM Hoekstra 《Radiation oncology (London, England)》2007,2(1):1-6