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71.
EH Schreiber 《Canadian Metallurgical Quarterly》1997,80(2):636-638
To examine whether group hypnosis would improve college students' achievement examination grades, including a midterm and final test of 30 educational psychology students who were hypnotized were compared with those of two control groups of 34 and 32 students. Analysis indicated for these intact classes the hypnotized group had a significantly higher mean score on final examination than those of the control groups, although differences in examination scores were nonsignificant at midterm. Suggestions for further research are made. 相似文献
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Voice disorders related to occupation and work environment are often observed in ENT consultations. Advising these patients requires not only the investigation of their vocal capacities but also knowledge about their vocal load. The patient will name extreme demands as the reason for vocal problems whereas the employer will want to know if the patient is capable of doing the work required of him. For an objective measurement of vocal load, a voice accumulator has been developed. This portable instrument records total speaking time and sound level over a period of several hours. The data can be transferred to a personal computer which analyses voiced time (s) between 60 and 112 dB(A)s. Thus, more precise and objective documentation of vocal demands in some professions can finally be obtained. With these results, it is possible to monitor vocal ability or disability during vocal rehabilitation. 相似文献
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B Frankenberger S Breitkopf E Albert S Scholz E Keller M Schattenkirchner EH Weiss H Kellner 《Canadian Metallurgical Quarterly》1997,24(5):899-903
OBJECTIVE: To evaluate the reproducibility and reliability of polymerase chain reaction (PCR) in HLA-B27 typing compared to the conventionally used microlymphocytotoxicity test (MLCT). To determine the HLA-B27 subtype frequencies (B*2701-B*2709) in patients with HLA-B27 associated disease and healthy persons using sequence specific oligonucleotides (SSO). METHODS: 398 consecutive patients were HLA-B27 typed by MLCT and PCR. Subtyping by SSO was performed in 142 patients with HLA-B27 associated disease [ankylosing spondylitis (AS) n = 38, reactive arthritis 44, undifferentiated spondyloarthropathy (uSpA) 45, psoriatic arthritis 15] and 125 healthy HLA-B27 controls. RESULTS: MLCT identified 61 HLA-B27 positive patients (15.3%); PCR identified 78 positive patients (19.6%). MLCT gave false negative results for 8 patients (2.0%) and false positives for a further 7 (1.8%). Only subtypes B*2702 and B*2705 were present in patients and controls. Overall frequencies of B*2702 in patients and controls were 14.1 and 9.6%, respectively. The B*2702 frequency was significantly (pcorr. < 0.04) higher in AS (23.7%) and lower in uSpA (6.7%) patients. CONCLUSION: HLA-B27 typing by PCR is reliable and reproducible and therefore recommended for routine typing. It overcomes the obstacles of serological typing, i.e., equivocal results and cross-reactivity. In addition, subtype frequencies (B*2702 and B*2705) are equally distributed among patients and controls, although subtype B*2702 seems to be more frequent in AS and less so in uSpA. 相似文献
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Human herpesvirus 8 (HHV-8) DNA sequences were examined in peripheral blood mononuclear cell (PBMC) DNA samples of 56 children, 15 healthy adults, and 10 renal transplant patients by the polymerase chain reaction (PCR). The PCR amplification was carried out using the published KS330(233) primer pairs to amplify HHV-8 DNA sequences. The PCR-amplified products were confirmed by Southern blot hybridization with radiolabeled 233 bp HHV-8 DNA fragment, which was cloned and sequenced from the PCR-amplified product of Kaposi's sarcoma tissue. Six PCR-amplified product of four children and two renal transplant patients were cloned and sequenced. HHV-8 DNA sequences were detected in 36 of 56 (64%) normal children, in 12 of 15 (80%) healthy adults, and in all 10 renal transplant patients by Southern blot hybridization of PCR-amplified products. Six PCR-amplified products were confirmed by sequencing. These results suggest that HHV-8 infection is prevalent in the Japanese population with infection occurring in early childhood. 相似文献
76.
The ribonucleoprotein (RNP) enzyme telomerase is required for replication of eukaryotic chromosomal termini. The RNA moiety of telomerase is essential for enzyme function and provides the template for telomeric DNA synthesis. However, the roles of its nontemplate domains have not been explored. Here we demonstrate that a novel interspecies telomerase RNA swap in vivo creates a functional but aberrant telomerase. Telomerase RNA from the ciliate Glaucoma chattoni was expressed in Tetrahymena thermophila cells. The telomerase RNAs from these two species have almost superimposable secondary structures. The template region base sequence is identical in the two RNAs, but elsewhere their sequences differ by 49%. This hybrid telomerase RNP was enzymatically active but added only short stretches of telomeric repeat tracts in vivo and in vitro. This new enzyme also had a strong, aberrant DNA cleavage activity in vitro. Thus, molecular interactions in the RNP involving nontemplate RNA domains affect specific aspects of telomerase enzyme function, raising the possibility that they may regulate telomerase activity. 相似文献
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The Escherichia coli RecA protein has served as a model for understanding protein-catalyzed homologous recombination, both in vitro and in vivo. Although RecA proteins have now been sequenced from over 60 different bacteria, almost all of our structural knowledge about RecA has come from studies of the E. coli protein. We have used electron microscopy and image analysis to examine three different structures formed by the RecA protein from the thermophilic bacterium Thermus aquaticus. This protein has previously been shown to catalyze an in vitro strand exchange reaction at an optimal temperature of about 60 degrees C. We show that the active filament formed by the T. aquaticus RecA on DNA in the presence of a nucleotide cofactor is extremely similar to the filament formed by the E. coli protein, including the extension of DNA to a 5.1-A rise per base pair within this filament. This parameter appears highly conserved through evolution, as it has been observed for the eukaryotic RecA analogs as well. We have also characterized bundles of filaments formed by the T. aquaticus RecA in the absence of both DNA and nucleotide cofactor, as well as hexameric rings of the protein formed under all conditions examined. The bundles display a very large plasticity of mass within the RecA filament, as well as showing a polymorphism in filament-filament contacts that may be important to understanding mutations that affect surface residues on the RecA filament. 相似文献