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In order to determine whether newer, possibly safer erythrocyte sedimenting agents could be used during centrifugal leukacytapheresis, we tested seven varieties of plant starch. Only waxy maize prepared by partial acid hydrolysis appeared suitable, and it was tested extensively on an analytical device developed especially for testing erythrocyte sedimentation under the conditions of residence time, force, and sedimenting agent concentration used in a cell separator. This species of waxy maize, however, was not quite as effective a sedimenting agent when compared to hydroxyethyl starch (HES 450/0.70) under the test conditions used. Although chromatographic analysis showed the average molecular weights of the unsubstituted waxy maize were considerably higher than those of HES 450/0.70, degradation of waxy maize to smaller molecular weight fragments occurred more rapidly. The rapid degradation of this material may offer significant advantages during centrifugal leukacytapheresis procedures, but additional studies of its storage stability are needed.  相似文献   
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We have used advanced endourologic techniques in the treatment of an obstructed lower-pole calycocystostomy site. The unusual clinical course that led to this problem and the interventional treatment used are discussed.  相似文献   
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We conducted an investigation of migraine headache in a general population of Mexican-Americans living in San Diego county. Specific headache triggers were reported and analyzed, the most frequently reported for females with migraine being missing meals (58.9%), weather changes (54.4%), menstruation (53.6%), post-crisis letdown (52.7%), and fatigue (51.8%). The most frequently reported trigger factors for migraines reported by males were fatigue (58.8%), sleep (as a precipitating factor) (56.3%), post-crisis letdown (41.2%), and weather changes (37.5%). Trigger factors were further evaluated using stratification by presence or absence of Raynaud's phenomenon (RP), menstrual migraine, family history of migraine, and by migraine type. Odds ratios and 95% confidence intervals were calculated. These results suggest that subjects with migraine and RP (perhaps indicative of a systematic vascular tone disorder) and those with menstrual migraine (indicative of sensitivity to hormonal changes) may overall be more sensitive to certain environmental stimuli, particularly those involving change in the internal environment.  相似文献   
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Doshi  PD; DiPersio  JF 《Blood》1994,84(8):2539-2553
The receptor for the human granulocyte-macrophage colony-stimulating factor (GM-CSF) (GM-R) is a heterodimeric complex consisting of two subunits, GM-R alpha and GM-R beta. Structural analyses have shown a number of highly conserved amino acid motifs present in both GM-R alpha and GM-R beta. These motifs include QYFLY, CXW, XW, and WSXWS motifs in the extracellular domain; a conserved cysteine in the transmembrane domain; and the entire cytoplasmic domain, including the LXVLX box in the carboxy terminal region of the cytoplasmic domain. We have investigated the role of these motifs in GM-R alpha by examining the effects of specific motif mutations on ligand binding and surface expression. Transient expression of these mutant GM-R alpha subunits in COS cells shows that these extracellular motis are essential for ligand binding. Alterations of the cytoplasmic region of GM-R alpha do not alter GM-CSF binding or the reconstitution of high-affinity receptors when coexpressed with GM-R beta. Permeabilization and immunostaining of cells transfected with mutant GM-R alpha subunits yields data suggesting that each of the mutant subunits is present in the cytoplasm. Immunostaining of both intact and permeabilized COS cells transiently transfected with wild-type or mutant GM-R alpha s showed that extracellular domain mutants accumulated in the cytoplasm and were not efficiently transported to the cell surface.  相似文献   
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