Search results for "Lee"
showing 10 items of 1847 documents
Ballasted Track Superstructures: Performance of Innovative Railway Sleepers
2012
A railway sleeper is the structural element which transversally connects the two rails by means of fastening components, thus ensuring its gauge. Its additional function is to firmly secure the track to the ballast and to distribute the loads transferred from railway carriages to the ballast. One of the most important parameters in the characterization of performance given by railway sleepers is represented by their lateral resistance to the sliding: the higher its value increases, the better the track stability becomes, thus reducing the frequency of maintenance interventions necessary to keep the superstructure efficient. This article focuses on the performance of two innovative railway s…
Do Extremely Bent Allenes Exist?
2009
Bent allenes: Theoretical calculations show that extremely bent allenes, cyclic or acyclic, adopt a ground state that only bears a formal relationship to classical allenes. Consequently, five-membered ring allenes favor a carbene-like electronic structure and formally contain a trivalent carbon(II) center. peerReviewed
ChemInform Abstract: Cyclooxygenase Inhibitors - Current Status and Future Prospects
2010
Prostaglandins are formed from arachidonic acid by the action of cyclooxygenase and subsequent downstream synthetases. Two closely related forms of the cyclooxygenase have been identified which are now known as COX-1 and COX-2. Both isoenzymes transform arachidonic acid to prostaglandins, but differ in their distribution and their physiological roles. Meanwhile, the responsible genes and their regulation have been clarified. COX-1, the pre-dominantly constitutive form of the enzyme, is expressed throughout the body and performs a number of homeostatic functions such as maintaining normal gastric mucosa and influencing renal blood flow and platelet aggregation. In contrast, the inducible for…
Modulation of immune parameters of roach, Rutilus rutilus, exposed to untreated ECF and TCF bleached pulp effluents
2000
Abstract The present study was designed to assess the effects of elemental chlorine free (ECF) and totally chlorine free (TCF) pulp and paper mill effluents on the immune defence of the roach ( Rutilus rutilus ). Fish were exposed for 5 weeks to concentrations of 0, 0.6, 2, 6 and 20% of untreated effluents from ECF or TCF bleaching processes. In order to study the capability to respond to foreign antigens the fish were immunised with bovine γ-globulin (BGG) 3 weeks before sampling. The numbers of anti-BGG antibody-secreting cells and immunoglobulin-secreting cells in the spleen and blood, as well as the levels of the anti-BGG antibodies and concentrations of immunoglobulin in plasma and the…
Ultraviolet B Irradiation Modulates the Immune System of Fish (Rutilus rutilus, Cyprinidae) Part III: Lymphocytes¶
2001
Abstract The effects of short-term exposure to ultraviolet B (UVB) radiation on lymphocyte-related parameters were studied under controlled laboratory conditions using roach (Rutilus rutilus), a cyprinid teleost, as the model fish. In vitro lymphoproliferative responses stimulated with a T-cell–specific mitogen, concanavalin A (ConA), or a B-cell–specific activator, lipopolysaccharide (LPS), were decreased in exposed fish. Also nonstimulated proliferation was lower than in unexposed fish. ConA-activated responses returned to normal levels within 7 days after exposure, but LPS-activated responses were reduced throughout the 14 day follow-up. The capability of UVB-exposed fish to produce an a…
Donor and host B cell-derived IL-10 contributes to suppression of graft-versus-host disease
2014
Graft-versus-host disease (GvHD) is a frequent life-threatening complication following allogeneic HSC transplantation (HSCT). IL-10 is a regulatory cytokine with important roles during GvHD, yet its relevant sources, and mode of action, remain incompletely defined in this disease. Using IL-10-deficient donor or host mice (BALB/c or C57BL/6, respectively) in a MHC-mismatched model for acute GvHD, we found a strongly aggravated course of the disease with increased mortality when either donor or host cells could not produce this cytokine. A lack of IL-10 resulted in increased allogeneic T-cell responses and enhanced activation of host DCs in spleen and MLNs. Remarkably, IL-10 was prominently p…
TRANSPLANTATION AND IN VITRO ANALYSIS OF SOYBEAN-AGGLUTININ SEPARATED MOUSE SPLEEN CELLS
1984
In human bone marrow allotransplantation, an in vitro method using soybean agglutinin(SBA) for enrichment of stem cells and depletion of mature T cells in the graft has been described (Reisner et al.;Lancet 2:1320,1980).To define the quality of the method,mouse spleen cells (C3H, C57/B6,BALB/c)containing about 30% of mature T cells were separated by SBA.The composition and functional capacity of the cell fraction known to contain the stem cells were characterized in vitro after each of two SBA-separation steps.In addition, the ability of the cell fraction to reconstitute successfully allogeneic irradiated (900R) mice was investigated. Only the two step SBA-separation procedure yielded satis…
Impact of Manaus City on the Amazon Green Ocean atmosphere: Ozone production, precursor sensitivity and aerosol load
2010
As a contribution to the Large-Scale Biosphere-Atmosphere Experiment in Amazonia – Cooperative LBA Airborne Regional Experiment (LBA-CLAIRE-2001) field campaign in the heart of the Amazon Basin, we analyzed the temporal and spatial dynamics of the urban plume of Manaus City during the wet-to-dry season transition period in July 2001. During the flights, we performed vertical stacks of crosswind transects in the urban outflow downwind of Manaus City, measuring a comprehensive set of trace constituents including O3, NO, NO2, CO, VOC, CO2, and H2O. Aerosol loads were characterized by concentrations of total aerosol number (CN) and cloud condensation nuclei (CCN), and by light scattering proper…
Validation of the ISTH/SSC bleeding assessment tool for inherited platelet disorders: A communication from the Platelet Physiology SSC
2020
Background: Careful assessment of bleeding history is the first step in the evaluation of patients with mild/moderate bleeding disorders, and the use of a bleeding assessment tool (BAT) is strongly encouraged. Although a few studies have assessed the utility of the ISTH-BAT in patients with inherited platelet function disorders (IPFD) none of them was sufficiently large to draw conclusions and/or included appropriate control groups. Objectives: The aim of the present study was to test the utility of the ISTH-BAT in a large cohort of patients with a well-defined diagnosis of inherited platelets disorder in comparison with two parallel cohorts, one of patients with type-1 von Willebrand disea…
A perioperative uncontrollable bleeding in an elderly patient with acquired hemophilia A: a case report
2013
Key Clinical Message Acquired hemophilia A should be taken into account in the differential diagnosis of perioperative bleeding in patients without any apparent reason for activated partial thromboplastin time prolongation.