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131.
The changes in nasal function which occur after septorhinoplasty for obstruction were investigated by anterior rhinomanometry in 15 subjects. Objective and subjective measures of outcome were compared. Anterior rhinomanometry was performed after nasal decongestion. These data were mathematically transformed to determine the amount of airflow asymmetry through the nostrils and the stiffness of the nasal valve. The results suggested that the presence of gross airflow asymmetry (> +/- 80%) in patients prior to surgery was a bad prognostic indicator for post-operative satisfaction with the airway. Patient satisfaction with function and cosmetic appearance post-operatively was correlated with the presence of symmetrical nasal airflow. Nasal valve stiffness did not seem to be affected by septorhinoplasty. 相似文献
132.
133.
Leukocyte transfusion-associated granulocyte responses in a patient with X-linked hyper-IgM syndrome
TP Atkinson CA Smith YM Hsu E Garber L Su TH Howard JT Prchal MP Everson MD Cooper 《Canadian Metallurgical Quarterly》1998,18(6):430-439
X-linked hyper-IgM syndrome (XHIM) is a severe congenital immunodeficiency caused by mutations in CD154 (CD40 ligand, gp39), the T cell ligand for CD40 on B cells. Chronic or cyclic neutropenia is a frequent complicating feature that heightens susceptibility to severe infections. We describe a patient with a variant of XHIM who produced elevated levels of serum IgA as well as IgM and suffered from chronic severe neutropenia. Eight of ten leukocyte transfusions with cells from a maternal aunt, performed because of mucosal infections, resulted in similar episodes of endogenous granulocyte production. Transfection studies with the mutant CD154 protein indicate that the protein is expressed at the cell surface and forms an aberrant trimer that does not interact with CD40. The data suggest that allogeneic cells from the patient's aunt, probably activated T cells bearing functional CD154, may interact with CD40+ recipient cells to produce maturation of myeloid precursors in the bone marrow. 相似文献
134.
Time-resolved small-angle X-ray scattering (TR-SAXS) was used to monitor the structural changes that occur upon the binding of the natural substrates to a mutant version of the allosteric enzyme aspartate transcarbamoylase from Escherichia coli, in which the creation of a critical link stabilizing the R state of the enzyme is hindered. Previously, SAXS experiments at equilibrium showed that the structures of the unligated mutant enzyme and the mutant enzyme saturated with a bisubstrate analog are indistinguishable from the T and R state structures, respectively, of the wild-type enzyme (Tauc et al., Protein Sci. 3:1998-2004, 1994). However, as opposed to the wild-type enzyme, the combination of one substrate, carbamoyl phosphate, and succinate, an analog of aspartate, did not convert the mutant enzyme into the R state. By using TR-SAXS we have been able to study the transient steady-state during catalysis using the natural substrates rather than the nonreactive substrate analogs. The steady-state in the presence of saturating amount of substrates is a mixture of 60% T and 40% R structures, which is further converted entirely to R in the additional presence of ATP. These results provide a structural explanation for the reduced cooperativity observed with the mutant enzyme as well as for the stimulation by ATP at saturating concentrations of substrates. They also illustrate the crucial role played by domain motions and quaternary-structure changes for both the homotropic and heterotropic aspects of allostery. 相似文献
135.
136.
TH Flewett 《Canadian Metallurgical Quarterly》1976,69(9):693-696
Weanling rats were fed either a semisynthetic diet with no fat, with 28% by wt partially hydrogenated fish oil, or with 28% by wt arachis oil(control diet) for 6 or 7 1/2 months. The in vitro conversion of arachidonic acid to prostaglandin E2 by homogenates of the rat kidney medulla was measured by gaschromatography with electron capture detection. The kidney medulla of essential fatty acid deficient animals showed increased activity for the in vitro conversion of exogenous arachidonic acid to prostaglandin E2 when compared to the controls. The change of the enzymatic activity in the essential fatty acid deficient animals was reversible, as shown by refeeding. Inhibition of the prostaglandin synthetase was found at exogenous substrate concentrations higher than 50-100 muM. 相似文献
137.
138.
Some results on the lateral diffusion of indium in thin lead films containing 2.5 wt.% Au are described. At room temperature the diffusion rate is high with a diffusion coefficient D of about 2.5 x 10-12 cm2 s-1 and an activation energy of 0.26±0.1 eV. The indium concentration profile along the films is highly irregular and is characterized by a sharp peak within the diffused film area at the diffusion front. Some of the irregularities are explained by the formation of filaments of near-stoichiometric AuIn2 and by diffusion around grains of varying size. The preferential formation of AuIn2 is likely to be the cause of the lower diffusion rate observed in the Pb-Au films in comparison with pure lead films. It is found that hillocks are nucleated in the vicinity of the indium diffusion front, indicative of strain relaxation. 相似文献
139.
A 61-year-old man presented to the emergency department after accidental exposure to beta radiation and low dose x radiation from an industrial linear electron accelerator. Over 40 days he developed burns on the extremities, abdomen, and face which eventually healed with topical silver sulfadiazine treatment, but suffered no acute x or gamma radiation symptoms. Beta burns and other radiation effects are discussed. 相似文献
140.
1,000 refugees living in Strasbourg have had a stoll parasitologic exam between 1986 and 1990. We have not retained results of South America and other areas of Asia subjects because of their scarce total number. Proportionally, the most numerous are the South East Asia Nationals (51.7%); followed by those from Middle East and Africa (20 and 15.5%) and more recently by those from East of Europe (5.2%). Their parasitic infestation's rate remains important (60.9%) but variable depending on their origin. Thus, people coming from Middle East and Africa are parasited mainly by protozoan, although those from South East Asia are parasited by helminths. It's interesant to notify that the prevalence of D. fragilis is ten times higher among East European people than in the common people. 相似文献