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971.
ST Fitzgerald M Hill B Santamaria C Howard R Jadack 《Canadian Metallurgical Quarterly》1996,44(2):78-83
In 7 patients who received liver transplants, 12 plasma proteins were subjected to phenotype analysis in donor and recipient before and after transplantation. The plasma proteins analyzed were haptoglobin, transferrin, glycoprotein GC, alpha-1-antitrypsin, complement factor 3 (C3), orosomucoid 1, properdin factor B, complement factor 6, alpha-2-HS-glycoprotein (A2HS), plasminogen, factor B of coagulation factor XIII, and interalpha-trypsin-inhibitor (ITI). Classification was done with isoelectric focusing or agarose gel electrophoresis (C3). A change from recipient to donor type was observed for all systems with the exception of C3. This is the first time such data have been obtained for the A2HS and ITI systems. The time is indicated at which the recipient type disappeared and the donor type appeared. In addition to the expected phenotype changes from recipient to donor type, unexpected results were found in some systems. For instance, in 2 patients a mixed type was synthesized, or new phenotypes appeared. Possible explanations include blood transfusions, immunosuppressive therapy, extrahepatic sites of synthesis and disturbed transplant function. The usefulness of phenotype determination as a diagnostic criterion for transplant function is discussed. 相似文献
972.
973.
Certain classes of particulate suspensions, consisting of semi-conducting, solid particles dispersed in an insulating carrier liquid, show a dramatic increase in flow resistance when placed under an external electric field. These so-called “electro-rheological fluids” have potential application in engineering devices such as tunable vibration damping systems. Under the field, a yield stress is induced in the fluid, and the characterisation of this quantity is essential for the design of many engineering devices. A new method for determining the yield stress is presented, which involves subjecting the sample to a constant shear stress and monitoring its shear rate after a step change in the electric field. It is found that this step field method can reproducibly determine the field-induced yield stress of a suspension of silica particles in silicon oil. 相似文献
974.
Phillips Susan D.; Pazienza Nicholas J.; Ferrin Howard H. 《Canadian Metallurgical Quarterly》1984,31(4):497
Administered measures of decision-making styles and problem-solving appraisal to 243 undergraduates and a canonical analysis was employed to examine the relationships between the 2 sets of variables. Three significant canonical roots suggest that (a) individuals who employ rational decision-making strategies are likely to approach (rather than avoid) problematic situations, (b) individuals who endorse dependent decisional strategies are likely to report that they approach problematic situations but do so without particular confidence in their problem-solving abilities, and (c) the endorsement of both rational and intuitive strategies for decision making is likely to be accompanied by appraisals of both greater confidence and diminished personal control. (27 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
975.
JG Tansley M Fatemian LS Howard MJ Poulin PA Robbins 《Canadian Metallurgical Quarterly》1998,85(6):2125-2134
Ventilatory acclimatization to hypoxia is associated with an increase in ventilation under conditions of acute hyperoxia (VEhyperoxia) and an increase in acute hypoxic ventilatory response (AHVR). This study compares 48-h exposures to isocapnic hypoxia (protocol I) with 48-h exposures to poikilocapnic hypoxia (protocol P) in 10 subjects to assess the importance of hypocapnic alkalosis in generating the changes observed in ventilatory acclimatization to hypoxia. During both hypoxic exposures, end-tidal PO2 was maintained at 60 Torr, with end-tidal PCO2 held at the subject's prehypoxic level (protocol I) or uncontrolled (protocol P). VEhyperoxia and AHVR were assessed regularly throughout the exposures. VEhyperoxia (P < 0.001, ANOVA) and AHVR (P < 0.001) increased during the hypoxic exposures, with no significant differences between protocols I and P. The increase in VEhyperoxia was associated with an increase in slope of the ventilation-end-tidal PCO2 response (P < 0.001) with no significant change in intercept. These results suggest that changes in respiratory control early in ventilatory acclimatization to hypoxia result from the effects of hypoxia per se and not the alkalosis normally accompanying hypoxia. 相似文献
976.
MB Fischer M Ma S Goerg X Zhou J Xia O Finco S Han G Kelsoe RG Howard TL Rothstein E Kremmer FS Rosen MC Carroll 《Canadian Metallurgical Quarterly》1996,157(2):549-556
We observed that retinoic acid, which differentiates the human neuroblastoma SK-N-BE into mature neurons, induced an elevation in levels of polyunsaturated fatty acids, especially arachidonic acid (20:4 n-6). This effect was not induced by phorbol myristate acetate, another differentiating agent. We then explored the effects of retinoic acid on the formation of arachidonic acid and of docosahexaenoic acid from precursors and on the de novo lipid synthesis from acetate at various stages of differentiation, which was assessed by morphological (cell number and neurite outgrowth) and biochemical (protein content and thymidine incorporation) criteria. At 3 days of incubation with retinoic acid, in the n-6 series, total conversion of linoleic acid, especially to 20:3 n-6, was elevated, in association with preferential incorporation of acetate into phospholipids; in contrast, at 8 days, synthesis of 20-carbon polyunsaturated fatty acids declined, in association with enhanced incorporation in triglycerides. In the n-3 series, eicosapentaenoic acid was converted to docosahexaenoic acid in SK-N-BE, but the conversion was not affected by retinoic acid. During the early stage of neuronal differentiation, therefore, enhanced production of 20-carbon polyunsaturated fatty acids from their precursors occurred, and newly formed fatty acids were preferentially incorporated in phospholipids, possibly in association with membrane deposition. When differentiation was completed, arachidonic acid formation and incorporation of acetate in phospholipids and cholesterol declined with enhanced labeling of storage lipids. 相似文献
977.
Four studies with college student participants examined the consistency, specificity, and correlates of sadness, fear, and anger. Study 1 measured emotions with daily diaries, and Study 2 examined the relationship between trait emotions and state emotions. Studies 1 and 2 indicated that specific negative emotions are temporally stable, are positively correlated, and provide information above and beyond that provided by other negative emotions. Study 3 found that negative emotions are differentially associated with different facets of cognitive style, as measured by questionnaires that examined dysfunctional attitudes and attributions concerning negative events. Study 4 indicated that negative emotions are differentially associated with different facets of response style, as measured by the degree to which individuals described their thoughts, feelings, and actions in response to hypothetical events. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
978.
979.
Affleck Glenn; Tennen Howard; Urrows Susan; Higgins Pamela; Abeles Micha; Hall Charles; Karoly Paul; Newton Craig 《Canadian Metallurgical Quarterly》1998,17(1):40
For 30 days, 50 women with primary fibromyalgia syndrome reported daily progress and effort toward a health–fitness and a social–interpersonal goal and the extent to which their pain and fatigue hindered their accomplishment. They also carried palmtop computers to assess their sleep and their pain, fatigue, and positive and negative mood throughout the day. Analyses of the person–day data set showed than on days during which pain or fatigue increased from morning to evening, participants perceived their goal progress to be more attenuated by pain and fatigue. Unrestorative sleep the night before predicted the following day's effort and progress toward accomplishing health–fitness goals, but not social–interpersonal goals. Finally, participants who reported more progress toward social–interpersonal goals on a given day were more likely to evidence improvements in positive mood across the day, regardless of any changes in pain or fatigue that day. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
980.
PCR/SSOP typing methods were used to analyze the HLA Class II DRB1, DQA1, DQB1 and DPB1 loci of samples from three African American populations of Colombia. Forty samples from the Cauca (Pacific), and twenty samples each from the Choco (North Pacific Coast) and the Providencia (Caribbean island) populations, were collected and the Class II loci analyzed under the auspices of the Expedicion Humana. Despite the limited number of samples analyzed, the African Colombian populations exhibit a very high degree of class II polymorphism. A great diversity of DRB1 alleles was found, with representatives from all serological classes, including 19 DRB1 alleles in the Providencia, 16 in the Cauca and 14 in the Choco groups. In addition, a novel DQB1*02 allele (*0203) was found in two individuals from the Cauca population of the Pacific Coast. The sequence of the DQB1*0203 allele, associated with DR3, differs from DQB1*0201 by only one nucleotide substitution (C-->A) in the second position of codon 57, resulting in an Ala to Asp change. The addition of DQB1*0203 brings the total number of DQB1 alleles identified to date to 26. HLA class II diversity is much greater in these African Colombian populations than that seen in nearby Amerindian populations. Analysis of regional Colombian African American HLA population genetics is discussed with respect to the Colombian Amerindian HLA genetics described in an accompanying paper. 相似文献