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151.
TP Le LW Church G Corradin RL Hunter Y Charoenvit R Wang P de la Vega J Sacci WR Ballou N Kolodny S Kitov GM Glenn RL Richards CR Alving SL Hoffman 《Canadian Metallurgical Quarterly》1998,16(2-3):305-312
Only low antibody levels were obtained from vaccinating human volunteers with single-chain peptide from the Plasmodium falciparum circumsporozoite protein (PfCSP). This resulted in modest protection against sporozoite challenge. In addition, HLA restriction limits the probability of synthesis of a vaccine effective for a diverse population. We report immunization studies with a multiple antigen peptide (MAP) system consisting of multiple copies of a B-cell epitope from the central repeat region of the PfCSP in combination with a universal T-cell epitope, the P2P30 portion of tetanus toxin. This MAP4(NANP)6P2P30 vaccine was highly immunogenic in four different strains of mice when used with various safe and nontoxic adjuvants. When this MAP vaccine was encapsulated in liposomes with lipid A and adsorbed to aluminium hydroxide and given three times at 4-week intervals, the resultant antibody prevented 100% of sporozoites from invading and developing into liver stage infection. This high degree of immunogenicity of MAP4(NANP)6P2P30 vaccine formulated in liposomes, lipid A and aluminum hydroxide provides the foundation for consideration of human trials with this formulation. 相似文献
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153.
Bleeding stomal varices is a rare complication of portal hypertension. We report the case of a cirrhotic patient, with a history of colonic adenocarcinoma, who had recurrent bleeding stomal varices. Treatment with transjugular intrahepatic portosystemic shunt and stomal varice embolization was performed because failure of medical treatment of portal hypertension and sclerotherapy. Twenty six months later only one stomal hemorrhage was noted. This suggests that transjugular intrahepatic portosystemic shunt and stomal varice embolization is effective in case of recurrent bleeding of stomal varices. 相似文献
154.
FA Manning N Bondaji CR Harman O Casiro S Menticoglou I Morrison DJ Berck 《Canadian Metallurgical Quarterly》1998,178(4):696-706
OBJECTIVE: The intent of this comparative clinical study was fourfold: (1) to determine the incidence of cerebral palsy in a large obstetric population, (2) to compare the incidence of cerebral palsy in patients at high risk referred for and managed according to the fetal biophysical profile score result with the incidence among unreferred and untested patients, (3) to determine the relationship, if any, between the last fetal biophysical profile score and the incidence of cerebral palsy, and (4) to categorize cases of cerebral palsy according to the clinical parameters and the probable time and nature of the damaging insult. STUDY DESIGN: In this retrospective 5-year comparative study (1987 to 1991) the incidence of cerebral palsy was determined by analysis of International Classification of Diseases, Ninth Revision, -coded related medical services. The clinical records were then sought and reviewed in index cases and obstetric, neonatal, and postnatal clinical data were abstracted. Cross-correlation with partial registries was done to confirm completeness of capture of index cases. The population of referred high-risk patients who received serial fetal biophysical profile scoring and were managed according to test results was determined by review of a prospective computer-stored database and by review of patient log books. The population of untested patients was calculated as the residual of total cases minus tested cases. The rate of cerebral palsy for all patients and for the tested and untested population was calculated and compared. The tested and untested perinates were compared for birth age, weight, and assigned timing or etiology of cerebral palsy. In the tested population the distribution of test results by last recorded biophysical profile score was determined and the relationship between the last test result and cerebral palsy and predictive accuracy parameters of the fetal biophysical profile score were calculated. RESULTS: The incidence of cerebral palsy among the 84,947 live births was 3.68 per 1000 live births (313 cases). The rate of cerebral palsy in the 26,290 referred high-risk tested patients was 1.33 per 1000 (35 cases) compared with a rate of 4.74 per 1000 live births in the 58,657 untested mixed low-risk/high-risk patients (278 cases). These differences were highly significant. A significant declining trend in the annual incidence of cerebral palsy was observed in the total population and the untested population, whereas the rate in the tested population remained relatively constant over the 5-year study interval. The differences in the cerebral palsy rate between the tested and untested population were not related to differences in gestational age, birth weight, or assigned timing or etiology category. In the tested population the relationship between the incidence of cerebral palsy and the last test fetal biophysical profile score was inverse, exponential, and highly significant. CONCLUSIONS: Antepartum assessment by fetal biophysical profile scoring is associated with a significant reduction in the incidence of cerebral palsy compared with untested patients. The relationship between the last test score and the incidence of cerebral palsy is inverse and exponential, suggesting that antenatal asphyxia is an important and potentially avoidable cause of cerebral palsy. 相似文献
155.
OBJECTIVE: To demonstrate the reversibility of retrograde ventriculo-atrial block by isoproterenol in patients with atrioventricular nodal reentrant tachycardia (AVNRT). DESIGN: Three case reports and their electrophysiological features. PATIENTS: Three patients with documented or suspected paroxysmal supraventricular tachycardia. INTERVENTIONS: At routine electrophysiology study, no supraventricular tachycardia was inducible in the baseline state. Infusion of isoproterenol (1 to 5 micrograms/min) was given and stimulation procedures were repeated. RESULTS: At baseline, all three patients had discontinuous antegrade atrioventricular (AV) nodal conduction, but very poor (two patients) or absent (one patient) ventriculo atrial conduction prevented induction of AVNRT. During infusion of isoproterenol, retrograde conduction was enhanced so that 1:1 retrograde occurred to cycle lengths of 300, 340 and 260 ms. AVNRT was then inducible in all patients, reproducing their clinical symptoms. CONCLUSION: Absent or poor ventriculo-atrial conduction in patients with suspected AV node reentry does not preclude the development of tachycardia with sympathomimetic enhancement. Isoproterenol should be given to attempt reversal of retrograde block in these patients. 相似文献
156.
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159.
CR Deible P Petrosko PC Johnson EJ Beckman AJ Russell WR Wagner 《Canadian Metallurgical Quarterly》1998,19(20):1885-1893
For cardiovascular biomaterials, thrombosis, thromboembolism and vascular graft occlusion are believed to be precipitated by the adsorption of proteins containing adhesive ligands for platelets. Polyethylene-glycol-diisocyanate (PEG-diisocyanate, 3400 MW) may potentially react with protein amines to form molecular barriers on adsorbed proteins on biomaterials, thereby masking adhesive ligands and preventing acute surface thrombosis. To test this notion, PE, PTFE, and glass microconduits were pre-adsorbed with fibrinogen and treated with PEG-diisocyanate, non-reactive PEG-dihydroxyl, or remained untreated. Following perfusion of 111In-labeled platelets in whole human blood for 1 min (wall shear rate = 312 s(-1)), PEG-diisocyanate treated surfaces experienced 96% (PE), 97% (PTFE) and 94% (glass) less platelet deposition than untreated surfaces. Similar reductions were seen for PEG-diisocyanate versus PEG-dihydroxyl treatment. Low shear perfusions of plasma for 1 h prior to blood contact did not reduce the inhibitory effect of PEG-diisocyanate. Platelet adhesion onto collagen-coated glass coverslips and platelet deposition onto preclotted Dacron were also reduced by treatment with PEG-diisocyanate (93 and 91%, respectively). Protein-reactive PEG may thus have utility in forming molecular barriers on surface-associated proteins to inhibit acute thrombosis on cardiovascular biomaterials. 相似文献
160.
Hope is the sum of goal thoughts as tapped by pathways and agency. Pathways reflect the perceived capability to produce goal routes; agency reflects the perception that one can initiate action along these pathways. Using trait and state hope scales, studies explored hope in college student athletes. In Study 1, male and female athletes were higher in trait hope than nonathletes; moreover, hope significantly predicted semester grade averages beyond cumulative grade point average and overall self-worth. In Study 2, with female cross-country athletes, trait hope predicted athletic outcomes; further, weekly state hope tended to predict athletic outcomes beyond dispositional hope, training, and self-esteem, confidence, and mood. In Study 3, with female track athletes, dispositional hope significantly predicted athletic outcomes beyond variance related to athletic abilities and affectivity; moreover, athletes had higher hope than nonathletes. 相似文献