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31.
Lyudmila N Soldatova Chaoming Tsai Ekaterina Dobrovolskaia Zora Markovi?-Housley Jay E Slater 《Allergy and asthma proceedings》2007,28(2):210-215
Honeybee venom hyaluronidase (Api m 2) is a major glycoprotein allergen. Previous studies have indicated that recombinant Api m 2 expressed in insect cells has enzyme activity and IgE binding comparable with that of native Api m 2. In contrast, Api m 2 expressed in Escherichia coli does not. In this study, we characterized the carbohydrate side chains of Api m 2 expressed in insect cells, and compared our data with the established carbohydrate structure of native Api m 2. We assessed both the monosaccharide and the oligosaccharide content of recombinant Api m 2 using fluorophore-assisted carbohydrate electrophoresis and HPLC. To identify the amino acid residues at which glycosylation occurs, we digested recombinant Api m 2 with endoproteinase Glu-C and identified the fragments that contained carbohydrate by specific staining. Recombinant Api m 2 expressed in insect cells contains N-acetylglucosamine, mannose, and fucose, as well as trace amounts of glucose and galactose, and the oligosaccharide analysis is consistent with heterogeneous oligosaccharide chains consisting of two to seven monosaccharides. No sialic acid or N-acetylgalactosamine were detected. These results are similar to published data for native Api m 2, although some monosaccharide components appear to be absent in the recombinant protein. Analysis of proteolytic digests indicates that of the four candidate N-glycosylation sites, carbohydrate chains are attached at asparagines 115 and 263. Recombinant Api m 2 expressed in insect cells has enzymic activity and IgE binding comparable with the native protein, and its carbohydrate composition is very similar. 相似文献
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33.
Eigenstructure assignment using output feedback is reformulated using an auxiliary principle of minimization of control effort. In the general eigenstructure assignment procedure, the feedback gain matrix is uniquely determined for a set of explicitly specified desired eigenvalues and eigenvectors. However, for the controller design proposed in this paper, only the most necessary constraints are imposed on the desired eigenvalues and eigenvectors, and the unspecified model parameters of the closed-loop system are determined by minimizing the control effort. Numerical examples are presented for comparison of the proposed method with standard eigenstructure assignment methods, and an experimental example gives an insight into the feasibility of the proposed control algorithm with application to the vibration control of flexible structures undergoing forced vibration. 相似文献
34.
JI Elizalde ; J Clemente ; JL Marin ; J Panes ; B Aragon ; A Mas ; JM Pique ; J Teres 《Transfusion》1997,37(6):573-576
BACKGROUND: Equilibration of hemoglobin concentration after transfusion has been estimated to take about 24 hours, but some studies have shown that earlier measurements reflect steady-state values in persons who have not bled recently. This study was aimed at assessing the changes over time in hemoglobin concentration after transfusion in acutely anemic patients because of recent bleeding. STUDY DESIGN AND METHODS: Thirty-two normovolemic patients recovering from an acute bleeding episode who were no longer thought to be bleeding and who received a 2- unit red cell transfusion were studied. At baseline and 15, 30, 60, and 120 minutes and 24 hours after transfusion, hemoglobin concentration and hematocrit values were measured. RESULTS: The administration of 2 units of packed red cells elicited a 24-hour increase of 22.4 +/− 6.8 g per L in hemoglobin concentration. Hemoglobin values were not different at any of the defined posttransfusion times. Hematocrit levels experienced similar changes over time. Agreement between 15-minute and 24-hour values was excellent, as only 6 percent of patients exhibited a clinically significant difference (> 6 g/L) between the hemoglobin measurements. CONCLUSION: Hemoglobin and hematocrit values rapidly equilibrate after transfusion in normovolemic patients who are recovering from an acute bleeding episode. This fact would allow a rapid assessment of the effects of transfusion and of the recurrence of bleeding in patients remaining at risk. 相似文献
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36.
This article describes the process and outcome of a needs assessment conducted to guide the development of interventions to increase repeat mammography use among participants in a federally funded cancer screening program. Health behavior theory and data from a phone survey are used to uncover key barriers to repeat mammography use and to identify fruitful intervention approaches for modifying them. Estimates of (a) compliance with mammography guidelines, (b) readiness to adopt regular mammography use, (c) the most common reasons for not being rescreened, and (d) population attributable risks associated with various predictors of repeat mammography use are presented and, with guidance from the transtheoretical model of behavior change, used to make inferences about the type of intervention strategies most appropriate for promoting repeat mammography use in this population. 相似文献
37.
Prevalence and Predictors of Adolescent Dating Violence 总被引:1,自引:0,他引:1
Patricia Y. Symons MSN RN CRNP Maureen W. Groër PhD RN Patricia Kepler-Youngblood MSW Victoria Slater MSN RN 《Journal of child and adolescent psychiatric nursing》1994,7(3):14-23
This study of 561 rural North Carolina adolescents examined relationships among race, parental educational level, family structure, parental discipline, family violence exposure, and dating violence experiences. The sample was predominantly female (77%), with 40% black and 58% white. The subjects ranged in age from 15 to 20 years; 80% of the adolescents were 16–18. Dating violence experiences were assessed by a researcher-constructed instrument measuring warning signs of potential violence and actual violent experiences. The results suggested that recognition of abusive relationships is difficult, with many adolescents denying such a relationship but actually reporting numerous abusive events. Sixty percent had experienced violent acts during dating relationships; 24% reported extreme violence (episodes of rape, use of weapons). More than 20% of the adolescents reported family violence and 2.2% reported family sexual abuse. The study suggests new avenues for research in adolescent date violence, and for interventions with high risk groups. 相似文献
38.
Andres A; Morales JM; Praga M; Campo C; Lahera V; Garcia-Robles R; Rodicio JL; Ruilope LM 《Nephrology, dialysis, transplantation》1997,12(7):1437-1440
BACKGROUND: Cyclosporin has been shown to facilitate renal vasoconstriction
and to have an antinatriuretic effect. The existence of an interference of
cyclosporin with the vasodilating properties of endothelium mediated by
nitric oxide production could mediate these effects. On the other hand, the
infusion of the nitric oxide precursor L-arginine has been shown to induce
renal vasodilatation and to facilitate natriuresis in normal volunteers. We
have investigated the renal effects of the administration of an infusion of
L-arginine in renal transplant patients chronically treated with
cyclosporin. To facilitate the analysis of the data the effects of the
administration of a similar dose of cyclosporin on renal function during
the infusion of a vehicle were also investigated during the administration
of a vehicle of L-arginine. DESIGN: Ten male renal transplant patients,
chronically treated with cyclosporin and with a stable renal function were
studied during 2 consecutive days after the administration of the usual
morning dose of cyclosporin. The first day they received an intravenous
infusion of vehicle and the second the infusion of graded doses of
L-arginine (50, 100, 150 mg/kg/h) during 3 consecutive h. RESULTS: The
first day, after cyclosporin administration a significant fall (P <
0.01) was observed in natriuresis and kaliuresis in the absence of changes
in renal plasma flow and glomerular filtration rate. After the
administration of L-arginine significant (P < 0.01) increases of renal
plasma flow, glomerular filtration rate, and natriuresis were seen. The
increase in blood levels of cyclosporin after its administration did not
differ between days 1 and 2. CONCLUSION: These results indicate that
L-arginine facilitates renal vasodilatation and natriuresis in renal
transplant patients. Furthermore, the observed increase in sodium excretion
could indicate that L-arginine counteracts the antinatriuretic effect of
cyclosporin.
相似文献
39.
40.
M Z Panos J V Anderson N Payne P Langley J D Slater L Rees R Williams 《Hepatology (Baltimore, Md.)》1992,16(1):82-88
Measurements of plasma atrial natriuretic peptide concentrations at 8 AM showed raised levels in 21 patients with cirrhosis and ascites (10.5 +/- 0.8 pmol/L) compared with levels in 10 age-matched controls (4.1 +/- 0.64 pmol/L; p less than 0.0001). In eight patients and 10 controls, atrial natriuretic peptide, plasma renin activity, plasma aldosterone and urinary sodium excretion were measured every 4 hr for 24 hr. Subjects were mobile between 8 AM and 11 PM and supine from 11 PM to 8 AM. In controls, urinary sodium excretion was highest between 4 PM and 11 PM (19.34 +/- 3.74 mumol/min) and lowest between midnight and 8 AM (7.06 +/- 1.23 mumol/min; p less than 0.001). In patients, urinary sodium excretion was 0.63 +/- 0.14 mumol/min between 4 PM and midnight and 1.85 +/- 0.71 mumol/min (p less than 0.08) between midnight and 8 AM. In patients during the day, mean plasma atrial natriuretic peptide concentration did not change despite large individual variation, but large, sustained rises in plasma renin activity and plasma aldosterone were seen. Correlations were noted between atrial natriuretic peptide and urinary sodium excretion between midnight and 8 AM (r = 0.65; p less than 0.02) and 4 PM and midnight (r = 0.54; p less than 0.05) but not between 8 AM and 4 PM. Plasma renin activity dropped from 12.54 +/- 2.49 at midnight to 7.41 +/- 0.88 pmol/hr/ml at 8 AM (p less than 0.05); plasma aldosterone decreased from 1,032 +/- 101 to 798 +/- 56 pmol/L (p less than 0.05).(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献