Big Chemical Encyclopedia

Chemical substances, components, reactions, process design ...

Articles Figures Tables About

Mast number

Mast setup distance The distance from the centerline of the well to a designated point on the mast structure defined by a manufacturer to assist in the setup of the rig. Maximum rated static hook load The sum of the weight applied at the hook and the traveling equipment for the designated location of the dead line anchor and the specified number of drilling lines without any pipe setback, sucker rod, or wind loadings. [Pg.501]

Asthma is a complex respiratory disorder that involves mast cell degranulation, mucous secretions, and smooth muscle hypertrophy and hyperresponsiveness. Smooth muscle hyperresponsiveness has suggested some defect in the regulation of smooth muscle contractility. Therefore, a number of studies concerning asthma have centered on whether alterations in the regulation of smooth muscle contraction (Figure 4) are responsible for hyperactivity in asthmatic airway smooth muscle. [Pg.72]

Mast cells express high-affinity IgE Fc receptors (FceRI) on their surface, contain cytoplasmic granules which are major sources of histamine and other inflammatory mediators, and are activated to release and generate these mediators by IgE-dependent and non-IgE-dependent mechanisms [1]. Disturbances either in the release of mast cell mediators or in mast cell proliferation are associated with clonal mast cell disorders including monoclonal mast cell activation syndrome (MMAS) and mastocytosis respectively, which are in turn associated with some cases of anaphylaxis [2], Molecular mechanisms have been identified which may link increased releasability of mast cell mediators and conditions leading to increased mast cell numbers [3]. Patients with mastocytosis have an increased risk to develop anaphylaxis [4, 5] and those with anaphylaxis may suffer from unrecognized mastocytosis or may display incomplete features of the disease [6-8]. [Pg.110]

Mastocytosis is a disorder characterized by increased numbers of mast cells in the skin, bone marrow, gastrointestinal tract, Uver, spleen, and lymph nodes [9,10]. The prevalence is unknown the incidence has been roughly estimated to be 3-7 new patients per million per year [9]. Most cases are sporadic with only a limited number (50-100) of cases with mastocytosis reported to pass from generation to generation [11], Mastocytosis presents at any age, although most cases occur during the first 2 years of life (childhood-onset) or after puberty (adult-onset) [9]. Mastocytosis in childhood often is self-limited and involves only the skin, whereas the course in patients with adult-onset disease is normally chronic and includes systemic involvement. [Pg.111]

Patients in the more aggressive categories are less likely to exhibit involvement of the skin and have a less favorable prognosis [10]. Those patients may have a definable hematological disorder such as a myelodysplastic syndrome, myeloproliferative disorder, acute leukemia, or a malignant lymphoma. In aggressive mastocytosis and mast cell leukemia, the clinical course is determined by the rapidity of the increase in mast cell numbers. [Pg.115]

Two immunoassays have been developed to measure tryptase in human fluids, one that measures mature a/(3-tryptases, i.e. total tryptase, available commercially, and one developed by Schwartz et al. [7] that measures both mature (3-tryptase and immature a/(3-tryptases. This distinction is of clinical relevance since immature tryptases reflect mast cell burden whereas mature tryptases indicate mast cell activation. Thus, for the diagnosis of anaphylaxis it would be extremely important to be able to differentiate between acute anaphylaxis and increases in tryptase due to increase in numbers of mast cells as happens in mastocytosis. Total tryptase would be high in both conditions, whereas mature tryptase will be only high in anaphylaxis but negligible in mastocytosis. [Pg.127]

A large number of cells are involved in the immune response and all are derived fiom the multipotential stem cells of the bone marrow. The predominant cell is the lymphocyte but monocytes-macrophages, endothelial cells, eosinophils and mast cells are also involved with certain immune responses. The two types of immunity (humoral and cell-mediated) are dependent on two distinct populations of lymphocytes, the B cells and the T cells respectively. Both the humoral and the cell-mediated systems interact to achieve an effective immune response. [Pg.285]

In the Multicenter Acute Stroke Trial Italy (MAST-I) study, 622 patients were randomized in a 2 X 2 factorial design to receive either a 1-hour infusion of 1.5 lU streptokinase or 300 mg aspirin or both, or neither. Streptokinase (alone or with aspirin) was associated with a greater number of fatahties at 10 days (OR 2.7,95% Cl 1.7. 3). In MAST-I, neither aspirin monotherapy nor combination therapy reduced the primary outcome of combined 6-month fatahty and severe disability. [Pg.144]

There are a number of side-effects of opiates that are due to their actions on opiate receptors outside the central nervous system. Opiates constrict the pupils by acting on the oculomotor nucleus and cause constipation by activating a maintained contraction of the smooth muscle of the gut which reduces motility. This diminished propulsion coupled with opiates reducing secretion in the gut underlie the anti-diarrhoeal effect. Opiates contract sphincters throughout the gastrointestinal tract. Although these effects are predominantly peripheral in origin there are central contributions as well. Morphine can also release histamine from mast cells and this can produce irritation and broncho-spasm in extreme cases. Opiates have minimal cardiovascular effects at therapeutic doses. [Pg.472]

Omalizumab is a recombinant humanized monoclonal anti-IgE antibody that inhibits binding of IgE to receptors on mast cells and basophils, resulting in the inhibition of mediator release and attenuation of the early- and late-phase allergic response. It may be a treatment option for moderate to severe persistent asthmatics 12 years of age or older whose asthma is not controlled by inhaled corticosteroids and who have a positive skin test or in vitro reactivity to perennial allergens.37 Omalizumab significantly decreases inhaled corticosteroid use, number and length of exacerbations, and increases asthma-related quality of life.37... [Pg.223]


See other pages where Mast number is mentioned: [Pg.42]    [Pg.498]    [Pg.74]    [Pg.116]    [Pg.521]    [Pg.229]    [Pg.488]    [Pg.541]    [Pg.588]    [Pg.1021]    [Pg.34]    [Pg.47]    [Pg.48]    [Pg.49]    [Pg.50]    [Pg.55]    [Pg.56]    [Pg.56]    [Pg.57]    [Pg.61]    [Pg.63]    [Pg.86]    [Pg.87]    [Pg.93]    [Pg.111]    [Pg.118]    [Pg.123]    [Pg.457]    [Pg.458]    [Pg.925]    [Pg.927]    [Pg.211]    [Pg.826]    [Pg.930]    [Pg.239]    [Pg.240]    [Pg.244]    [Pg.245]    [Pg.305]    [Pg.82]    [Pg.15]   
See also in sourсe #XX -- [ Pg.3 ]




SEARCH



Masts

© 2024 chempedia.info