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141.
142.
HG Morrison EJ Weil SI Karchner ML Sogin JJ Stegeman 《Canadian Metallurgical Quarterly》1998,121(1-3):231-240
Since we published a phylogenetic analysis of the CYP1A subfamily in 1995, several additional full-length sequences have been reported, including three members of an entirely new subfamily, CYP1B. Two avian sequences were recently published, so that CYP1A sequence data are now available from three of the five major vertebrate lineages. The two new branches that have been added to the CYP1 family tree significantly add to our understanding of P450 evolution. The inclusion of the CYP1Bs to the phylogenetic analysis allows us to root inferred trees. Addition of the avian CYP1As indicates that the CYP1A1/CYP1A2 duplication present in the mammalian lineage may have occurred after the divergence of birds and mammals. The number of fish species from which full-length coding regions of CYP1A genes have been sequenced has increased from four (trout, plaice, toadfish, and scup) to nine. These include CYP1A sequences from tomcod, butterflyfish, sea bream, sea bass, and the full-length sequence of CYP1A from the killifish Fundulus heteroclitus that is reported here. Phylogenetic analyses incorporating the new fish CYP1A sequences support our original conclusion that the fish CYP1As are monophyletic and indicate that the genes are evolving at very different rates in different species. 相似文献
143.
S Ginanni Corradini G Yamashita H Nuutinen A Chernosky C Williams L Hays ML Shiffman RM Walsh J Svanvik P Della Guardia L Capocaccia RT Holzbach 《Canadian Metallurgical Quarterly》1998,43(2):335-343
OBJECTIVES: Fructose-1,6-diphosphate is a glycolytic intermediate that has been shown experimentally to cross the cell membrane and lead to increased glycolytic flux. Because glycolysis is an important energy source for myocardium during early reperfusion, we sought to determine the effects of fructose-1,6-diphosphate on recovery of postischemic contractile function. METHODS: Langendorff-perfused rabbit hearts were infused with fructose-1,6-diphosphate (5 and 10 mmol/L, n = 5 per group) in a nonischemic model. In a second group of hearts subjected to 35 minutes of ischemia at 37 degrees C followed by reperfusion (n = 6 per group), a 5 mmol/L concentration of fructose-1,6-diphosphate was infused during the first 30 minutes of reperfusion. We measured contractile function, glucose uptake, lactate production, and adenosine triphosphate and phosphocreatine levels by phosphorus 31-nuclear magnetic resonance spectroscopy. RESULTS: In the nonischemic hearts, fructose-1,6-diphosphate resulted in a dose-dependent increase in glucose uptake, adenosine triphosphate, phosphocreatine, and inorganic phosphate levels. During the infusion of fructose-1,6-diphosphate, developed pressure and extracellular calcium levels decreased. Developed pressure was restored to near control values by normalizing extracellular calcium. In the ischemia/reperfusion model, after 60 minutes of reperfusion the hearts that received fructose-1,6-diphosphate during the first 30 minutes of reperfusion had higher developed pressures (83 +/- 2 vs 70 +/- 4 mm Hg, p < 0.05), lower diastolic pressures (7 +/- 1 vs 12 +/- 2 mm Hg, p < 0.05), and higher phosphocreatine levels than control untreated hearts. Glucose uptake was also greater after ischemia in the hearts treated with fructose-1,6-diphosphate. CONCLUSIONS: We conclude that fructose-1,6-diphosphate, when given during early reperfusion, significantly improves recovery of both diastolic and systolic function in association with increased glucose uptake and higher phosphocreatine levels during reperfusion. 相似文献
144.
Through change workshops, nurses can manage their emotions experienced during restructuring, such as losing familiarity, becoming insecure in their jobs, and grieving the loss of coworkers. The workshops focused on three themes: reminiscence, survival, and celebration. 相似文献
145.
A new instrument is presented which is capable of high resolution acoustic imaging at relatively low frequencies. This approach results in increased complexity of the signal processing required and reduced throughput of the instrument. However, these disadvantages are amply compensated by the ability to create velocity scan images of materials with either high attenuation or low material velocities. These measurements are not possible using traditional/acoustic microscopes. The initial performance of the new instrument is demonstrated using thin samples of shim materials to show that acceptable spatial resolution and highly accurate time delay measurements are possible. An application is then shown using the instrument to evaluate subchondral sclerosis in horse bones. It has been hypothesized that changes in the elastic modulus may be associated with fatigue-induced microdamage. The modulus change may further represent bone damage which precedes the development of microcracking. Thin samples are used to allow complementary microradiography to be performed on the bone slices. Because of the low material velocity, surface wave interference methods (so called V(z) curves) are not well suited for use in some bone samples. The thickness of the samples eliminates the potential for the samples to be evaluated using pulse-echo time delay measurements. The new instrument is thus unique in its ability to create velocity scans of these samples. 相似文献
146.
KJ Greenlund WH Giles NL Keenan JB Croft ML Casper D Matson-Koffman 《Canadian Metallurgical Quarterly》1998,7(9):1125-1133
We sought to examine the prevalence of self-reported multiple cardiovascular disease (CVD) risk factors (hypertension, high blood cholesterol, diabetes, overweight, and current smoking) among women in 1992 and 1995 in the United States using data from the Behavioral Risk Factor Surveillance System. In 1992, 37.5%, 34.4%, and 28.1% of women had zero, one, and two or more of the five risk factors, respectively. In 1995, the respective estimates were 35.5%, 34.3%, and 30%. In both years, the prevalence of two or more risk factors increased with age, decreased with educational level, was higher among black women (lowest among Hispanic women and women of other ethnic groups), and higher among women reporting cost as a barrier to healthcare. The percentage of women with two or more risk factors was higher in 1995 than in 1992 for 35 of 48 states, being statistically significant for 7 states. The percentage of women with at least two risk factors was not significantly lower in 1995 than in 1992 for any state. A higher percentage of women reported having multiple CVD risk factors in 1995 compared with 1992. A multifactorial approach to primary prevention and risk factor reduction should be encouraged to help reduce the prevalence and burden of CVD among women. 相似文献
147.
B Major C Richards ML Cooper C Cozzarelli J Zubek 《Canadian Metallurgical Quarterly》1998,74(3):735-752
We hypothesized that the effects of personality (self-esteem, control, and optimism) on postabortion adaptation (distress, well-being, and decision satisfaction) would be fully mediated by preabortion cognitive appraisals (stress appraisals and self-efficacy appraisals) and postabortion coping. We further proposed that the effects of preabortion appraisals on adaptation would be fully mediated by postabortion coping. Results of a longitudinal study of 527 women who had first-trimester abortions supported our hypotheses. Women with more resilient personalities appraised their abortion as less stressful and had higher self-efficacy for coping with the abortion. More positive appraisals predicted greater acceptance/reframing coping and lesser avoidance/denial, venting, support seeking, and religious coping. Acceptance-reframing predicted better adjustment on all measures, whereas avoidance-denial and venting related to poorer adjustment on all measures. Greater support seeking was associated with reduced distress, and greater religious coping was associated with less decision satisfaction. 相似文献
148.
G Martinez ML Carnazza C Di Giacomo V Sorrenti M Avitabile A Vanella 《Canadian Metallurgical Quarterly》1998,16(6):519-526
Mutation of the TP53 gene is one of the most common molecular alterations in a variety of tumors, but it occurs infrequently in childhood and adult hematological malignancies. Protein accumulation often results from mutations that lead to inactivation of the p53 protein. Other causes of functional inactivation of the p53 protein include stabilization of p53 via proteins such as MDM2, an oncoprotein capable of forming specific complexes with p53. In the present study, protein expressions of MDM2 and p53 were investigated by immunohistochemistry from bone marrow samples in 23 patients with acute lymphoblastic leukemia aged 1-13 years at diagnosis. p53 protein overexpression was detected in only one case, while overexpression of MDM2 was detected in samples from five patients. All five patients overexpressing MDM2 belonged to a group with unfavorable prognostic signs at diagnosis and three of them relapsed or died within 6 months after diagnosis. 相似文献
149.
150.
HW Harris C Hosselet L Guay-Woodford ML Zeidel 《Canadian Metallurgical Quarterly》1992,267(31):22115-22121
Antidiuretic hormone (ADH) increases toad bladder granular cell apical membrane osmotic water permeability (Pf) by insertion of cytoplasmic vesicles containing water channels into the apical membrane. Termination of ADH stimulation results in endocytosis of water channel-containing membrane. In previous work, we have purified water channel-containing vesicles and demonstrated that they contain 12 major protein bands when analyzed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). On the basis of vectorial labeling studies of granular cells and purified vesicles, we have proposed previously that vesicle proteins of 55, 53, and 17 kDa are ADH water channel components. In this report, we have purified and analyzed these three proteins using a combination of SDS-PAGE, peptide mapping, amino acid composition, and amino-terminal analyses. The 55- and 53-kDa proteins are distinct protein species possessing a high degree of structural similarity. Both possess a large content of cysteine. The 17-kDa protein appears to be a proteolytic fragment of the 53-kDa protein. None of these three proteins is phosphorylated or contains large amounts of covalently linked carbohydrate. ADH-elicited Pf is inhibited by the organic mercurial reagent fluorescein mercuric acetate (FMA). Exposure of water channel-containing vesicles to FMA labels selectively four vesicle proteins of 92, 55, 53, and 29 kDa while reducing vesicle Pf by 82%. The combination of FMA and 2-mercaptoethanol or exposure to another mercurial reagent, n-ethylmaleimide, does not inhibit vesicle Pf. Together, these data provide additional evidence for the role of the 55- and 53-kDa proteins as components of the ADH water channel. These candidate ADH water channel proteins are distinct from a 28-kDa candidate water channel protein (CHIP 28) isolated recently from human erythrocyte membranes and kidney proximal tubule by Agre and co-workers (Preston, G. M., Carroll, T. P., Guggino, W. B., and Agre, P. (1992) Science 256, 385-387). 相似文献