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101.
I Str?m 《Canadian Metallurgical Quarterly》1993,113(16):2012-2013
102.
103.
B Bj?rkholm M Granstr?m J Taranger M Wahl L Hagberg 《Canadian Metallurgical Quarterly》1995,14(10):846-850
Diphtheria antitoxin was determined in serum from 44 pregnant women, of whom 26 had received one injection of diphtheria toxoid during pregnancy. Their infants were vaccinated with a combined diphtheria-tetanus vaccine at 3, 5 and 12 months of age. This vaccination schedule has been used in Sweden since 1986, replacing the old schedule of vaccination at 3, 4.5 and 6 months of age originally designed for diphtheria-tetanus-pertussis vaccine, which had not been used after cessation of general vaccination against pertussis in 1979. Serum samples from the infants were obtained at 3, 7 and 18 months of age. After 2 injections infants of mothers with high antitoxin titers, > or = 0.1 IU/ml, tended to have lower antitoxin titers than infants of mothers with low antitoxin concentrations (P = 0.067). All children had, however, antitoxin above the minimum protective level of 0.01 IU/ml. Median antitoxin titers were 1.6 IU/ml in both groups after the third booster injection. Four infants of mothers who had been vaccinated during pregnancy and who had titers of > or = 0.4 IU/ml did not reach the 0.1 IU/ml level after 2 injections: all 4 responded with high antitoxin titers after the third dose. Thus all infants were primed by 2 doses of vaccine, irrespective of maternal antibody concentration. The repressive effect of maternal antibody on titers noted after 2 doses was no longer observed after the third, booster dose. 相似文献
104.
The purpose of this study was to examine the relationship of job satisfaction to job difficulty and worthiness, reported by the clinical psychologists who worked at medical institutions. A mail survey of 748 clinical psychologists working at hospital and clinics revealed the following results. First, job satisfaction was related more to job situation than job content. Also, job satisfaction was low among those who worked at non-university psychiatric or geriatric hospitals, who did not practice psychotherapy, and who were not in education, research, or management. In addition, compared to the high job satisfaction group, the low group perceived more incongruity between institutional climate and their psychological work, felt being less valued by other professionals, were less able to function fully as a practicing psychologist, and experienced more role ambiguity as a clinical psychologist in a hospital setting. 相似文献
105.
J Bunikis L Noppa Y Ostberg AG Barbour S Bergstr?m 《Canadian Metallurgical Quarterly》1996,64(12):5111-5116
A chromosomally encoded 66-kDa protein (P66) of Borrelia spp. that cause Lyme disease has previously been shown to be associated with the spirochetal outer membrane. A topological model of P66 predicts a surface-exposed fragment which links the N- and C-terminal intramembranous domains of the protein (J. Bunikis, L. Noppa, and S. Bergstr?m, FEMS Microbiol. Lett. 131:139-145, 1995). In the present study, an immunogenic determinant of P66 was identified by a comparison of the immunoreactivities of different fragments of P66 generated either by proteolytic treatment of intact spirochetes or as recombinant proteins expressed in Escherichia coli. The immune response to P66 during natural infection was found to be directed against the predicted surface domain which comprises amino acids at positions 454 through 491. A sequence comparison revealed considerable polymorphism of the surface domains of P66 proteins of different Lyme disease-causing Borrelia species. Five sequence patterns of this domain were observed in the B. garinii strains studied. In contrast, sequences of the relevant part of P66 of the B. afzelii and B. burgdorferi sensu stricto isolates studied were identical within the respective species. In immunoblotting, 5 of 17 (29.4%) sera from North American patients with early disseminated or persistent Lyme disease reacted against P66 of B. burgdorferi sensu stricto B31. These sera, however, failed to recognize P66 of B. afzelii and B. garinii, as well as an analog of P66 in the relapsing fever agent, B. hermsii. In conclusion, the topological model of P66 is supported by the demonstration of an apparent surface localization of an immunoreactive domain of this protein. Furthermore, analogous to the plasmid-encoded borrelial outer surface proteins, the predicted surface-exposed portion of chromosomally encoded P66 appears to be antigenically heterogenous. 相似文献
106.
107.
Catalytic chlorination of methane was studied over SO
4
2–
/ZrO2, Pt/SO
4
2–
/ZrO2, and Fe/Mn/SO
4
2–
/ZrO2 solid superacid catalysts. The reactions were carried out in a continuous flow reactor under atmospheric pressure, at temperatures below 240°C, with a gaseous hourly space velocity of 1000 ml/g h and a methane to chlorine ratio of 4 to 1. At 200°C with 30% chlorine converted the selectivity in methyl chloride exceeds 90%. At more elevated temperatures, the selectivity decreases but stays above 80% in methyl chloride at 225°C using the sulfated zirconia catalysts. The selectivity can be enhanced by adding platinum to sulfated zirconia catalysts. An iron and manganese-doped catalyst exhibited excellent selectivities at somewhat lower conversions. Methyl chloride is obtained at 235°C in selectivities greater than 85%. No chloroform or carbon tetrachloride is formed. The electrophilic insertion involves electron-deficient metal-coordinated chlorine into the methane C-H bond.Catalysis by solid superacids, 29. For part 28 see ref. [14]. 相似文献
108.
K Carlstr?m 《Canadian Metallurgical Quarterly》1997,94(32-33):2714-2715
109.
Summary Surface morphology and molecular arrangement have been recorded by atomic force microscopy (AFM) on polytetrafluoroethylene (PTFE) and on polycarbonate (PC) films. In a thin layer of PTFE deposited by rubbing polymer on hot glass substrate unidirectional orientation of polymer has been revealed. Individual polymer chains have been visualized. An interchain distance of .53 nm and several periodicities along the chain contours have been found-.44 nm, .62 nm and .82 nm-in accordance with a 13/6 helix.The monitoring of surface changes during thermal treatment of amorphous-bis-phenol A-PC film has been realized by AFM. Different types of surface morphology were revealed. Spherulites are formed during polymer crystallization. In most cases, however, numerous nanocrystallites appeared after thermal treatment. On their surfaces well-ordered atomic scale AFM images have been received. The arrangement of AFM patterns can be characterized by periodicities of .50 nm and .52 nm in the orthogonal directions. Polycarbonate oligomers-as the product of surface degradation-effectively might form the observed nanocrystallites.Prof. Dr. G. Zachmann zum 60. Geburtstag herzlichst gewidmetThese results were given by us first in a lecture in Baltimore, at the 5th ISPAC Symposium on May 31, 1991, and in a lecture in Santa Barbara, at the Nanoscope Users Meeting on June 25, 1991 相似文献
110.
N Schaap A Schattenberg B B?r F Preijers A Geurts van Kessel R van der Maazen T de Boo T de Witte 《Canadian Metallurgical Quarterly》1997,98(3):750-759
One hundred and eighty-one consecutive patients with standard-risk leukaemia were transplanted with HLA-identical sibling grafts depleted of lymphocytes using counter-flow centrifugation. In 116 patients, standard conditioning was intensified by the addition of anthracyclines. Multivariate analysis revealed significantly more acute GVHD > or = grade 2 and a trend towards more chronic GVHD in patients conditioned with the addition of anthracyclines. For all patients the risk for chronic GVHD, but not for acute GVHD increased with a higher number of T cells in the graft. The projected 5-year probability of relapse was significantly lower in the group of patients conditioned with anthracyclines; 26% versus 52% (P = 0.015). In multivariate analysis the addition of anthracyclines to the conditioning regimen was the only significant factor contributing to a lower probability of relapse. The projected 5-year probability of leukaemia-free survival [LFS] in the patients conditioned with and without the addition of anthracyclines was 56% and 36%, respectively (P = 0.004). In multivariate analysis the addition of anthracyclines to the conditioning regimen correlated significantly with a lower number of mixed chimaeras in patients at 6 and 12 months after BMT. Mixed chimaerism at 6 months after transplantation did not significantly correlate with a higher incidence of relapse in further follow-up. In contrast, mixed chimaerism at 12 months after BMT was significantly associated with higher relapse rate. We conclude that the addition of anthracyclines to the conditioning regimen improves outcome of BMT using T-cell-depleted grafts. 相似文献