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51.
Zusammenfassung Mikrokallusformationen lassen sich in nahezu allen Skelettabschnitten der Spongiosa nachweisen. Mikrokallus besteht aus Geflechtknochen, der sich an lokal überbelasteten Stellen in der Spongiosa bildet. Mit Hilfe einer speziellen Pr?parationstechnik wurden 26 skelettgesunde und 11 Wirbels?ulen von F?llen mit Osteoporose untersucht. Mikrokallusformationen finden sich bevorzugt bei Frauen ?lter als 45 Jahre in den unteren Wirbels?ulenabschnitten. Dabei hat die Mikroarchitektur der Spongiosa (TBPf) einen st?rkeren Einflu? auf die Anzahl der Mikrokalli, als individuelle Trabekelparameter (Tb.N, BV/TV und Tb.Th). Nur in 33 % der Formationen lassen sich Frakturspalten nachweisen. Mikrokallusformationen k?nnen nichtinvasive Knochenmassemessungen verf?lschen. Auch wenn Mikrokallusformationen Indikatoren für eine Instabilit?t der Spongiosa sind, tragen sie zur Knochenregeneration bei, und die Entstehung neuer Trabekel ist durch sie m?glich. Die Vorstellung, da? Osteoporose das Resultat einer verminderten Mikrokallusbildung ist, trifft nicht zu.   相似文献   
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A cross-sectional study of 8204 children was performed to investigate the prevalence of immunization against measles, mumps and rubella and possible determinants of immunization uptake. The study was approached from a Lewinian perspective on preventive behaviour. Seventy-one questions referring to the guardian of the child, his or her partner, the household and the child, as well as to immunization-related experiences and situational topics were asked. Two psychological variables were studied: health locus of control and subjective relevance concerning measles. The immunization rate was 77.7 percent [95 percent confidence interval 76.8-78.6]. Multiple logistic regression yielded the following odds ratios for non- uptake of measles immunization: natural health orientation 8.74 [6.72-11.37]; advice of paediatrician 6.02 [4.67-7.75]; dangerousness of measles 2.00 [1.53-2.60]; marital status 1.87 [1.31-2.51]; assessed reliability of vaccination 1.57 [1.23-2.01]; smoking 1.55 [1.21-1.98]; and number of siblings 1.55 [1.21- 1.98]. Parents or guardians of immunized children were more internal and assessed measles as more relevant than those of non- immunized children.  相似文献   
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The aims of this work were to measure the accuracy of one continuous speech recognition product and dependence on the speaker's gender and status as a native or nonnative English speaker, and evaluate the product's potential for routine use in transcribing radiology reports. IBM MedSpeak/Radiology software, version 1.1 was evaluated by 6 speakers. Two were nonnative English speakers, and 3 were men. Each speaker dictated a set of 12 reports. The reports included neurologic and body imaging examinations performed with 6 different modalities. The dictated and original report texts were compared, and error rates for overall, significant, and subtle significant errors were computed. Error rate dependence on modality, native English speaker status, and gender were evaluated by performing ttests. The overall error rate was 10.3 +/- 3.3%. No difference in accuracy between men and women was found; however, significant differences were seen for overall and significant errors when comparing native and nonnative English speakers (P = .009 and P = .008, respectively). The speech recognition software is approximately 90% accurate, and while practical implementation issues (rather than accuracy) currently limit routine use of this product throughout a radiology practice, application in niche areas such as the emergency room currently is being pursued. This methodology provides a convenient way to compare the initial accuracy of different speech recognition products, and changes in accuracy over time, in a detailed and sensitive manner.  相似文献   
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Mimotope and anti-idiotypic vaccines to induce an anti-IgE response   总被引:1,自引:0,他引:1  
We have defined epitopes on human IgE by screening different phage display random peptide libraries with a monoclonal anti-IgE antibody termed BSW17. The selected mimotopes and epitopes within the Cepsilon3 and Cepsilon4 region of IgE induced antibodies that were nonanaphylactogenic and had biological activity similar to BSW17. The chemically synthesized and KLH-coupled IgE epitopes or mimotopes were used to induce an anti-IgE response in rhesus monkeys. The immunized rhesus monkeys were subsequently protected in a PCA test when sensitized with human IgE and triggered with the corresponding allergen. Furthermore, using the same monoclonal anti-IgE antibody, we also generated an anti-idiotypic antibody that showed sequence homology with the IgE epitope in the Cepsilon3 domain. This anti-idiotypic antibody as well as the mimotopes were then used in a mouse model to induce orally an anti-IgE immune response. For this purpose mice were fed by intragastric gavages with bacteriophages displaying the small IgE-homologous structures. Orally immunized mice produced serum anti-IgE antibodies that were inhibited by BSW17 suggesting that it may be possible to induce a systemic anti-IgE response orally.  相似文献   
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This paper describes the development of a murine bank of monoclonal antibodies against Bordetella pertussis toxin, filamentous hemagglutinin (FHA), pili, lipopolysaccharide (LPS), or outer membrane proteins (OMPs). Subunits S1, S2, S3 of pertussis toxin (PT) bound immunoglobulins and glycoproteins such as fetuin and haptoglobin in an unspecific manner. The specificity of monoclonal antibodies towards subunits S1, S2, S3 or S4 of PT could be demonstrated by using purified immunoglobulins or their Fab2 fragments. A set of FHA-specific monoclonal antibodies could be differentiated on the basis of their binding to the various breakdown products present in FHA preparations. Pili-specific monoclonal antibodies reacted with either native pili or denatured pilin, and both demonstrated serotype specificity. Monoclonal antibodies to Bordetella pertussis OMPs were directed to either the virulent phase-regulated trypsin-sensitive, detergent-extractable OMPs 92 kDa, 32 kDa, and 30 kDa or the non-virulent phase-expressed, not-trypsin sensitive OMPs 38 kDa, 33kDa, and 18 kDa.  相似文献   
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