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61.
The Ilizarov method has broad applications for the generation of bone and soft tissue via an external fixator composed of small pins, tensional wires, rings, hinges and distractors. The success of the technique depends on adherence to Ilizarov's principles of tension-stress phenomenon: preservation of the tissues' blood supply, frequent distraction in small increments, and full function of the extremity. 相似文献
62.
EH Uhlenhuth PE Alexander GM Dempsey W Jones BS Coleman AM Swiontek 《Canadian Metallurgical Quarterly》1998,47(1-3):183-190
Heart sounds produce an incessant noise during lung sounds recordings. This noise severely contaminates the breath sounds signal and interferes in the analysis of lung sounds. In this paper, the use of a wavelet transform domain filtering technique as an adaptive de-noising tool, implemented in lung sounds analysis, is presented. The multiresolution representations of the signal, produced by wavelet transform, are used for signal structure extraction. In addition, the use of hard thresholding in the wavelet transform domain results in a separation of the nonstationary part of the input signal (heart sounds) from the stationary one (lung sounds). Thus, the location of the heart sound noise (1st and 2nd heart sound peaks) is automatically detected, without requiring any noise reference signal. Experimental results have shown that the implementation of this wavelet-based filter in lung sound analysis results in an efficient reduction of the superimposed heart sound noise, producing an almost noise-free output signal. Due to its simplicity and its fast implementation the method can easily be used in clinical medicine. 相似文献
63.
64.
Estimates of the prevalence of arthritis and selected musculoskeletal disorders in the United States 总被引:3,自引:0,他引:3
RC Lawrence CG Helmick FC Arnett RA Deyo DT Felson EH Giannini SP Heyse R Hirsch MC Hochberg GG Hunder MH Liang SR Pillemer VD Steen F Wolfe 《Canadian Metallurgical Quarterly》1998,41(5):778-799
OBJECTIVE: To provide a single source for the best available estimates of the national prevalence of arthritis in general and of selected musculoskeletal disorders (osteoarthritis, rheumatoid arthritis, juvenile rheumatoid arthritis, the spondylarthropathies, systemic lupus erythematosus, scleroderma, polymyalgia rheumatica/giant cell arteritis, gout, fibromyalgia, and low back pain). METHODS: The National Arthritis Data Workgroup reviewed data from available surveys, such as the National Health and Nutrition Examination Survey series. For overall national estimates, we used surveys based on representative samples. Because data based on national population samples are unavailable for most specific musculoskeletal conditions, we derived data from various smaller survey samples from defined populations. Prevalence estimates from these surveys were linked to 1990 US Bureau of the Census population data to calculate national estimates. We also estimated the expected frequency of arthritis in the year 2020. RESULTS: Current national estimates are provided, with important caveats regarding their interpretation, for self-reported arthritis and selected conditions. An estimated 15% (40 million) of Americans had some form of arthritis in 1995. By the year 2020, an estimated 18.2% (59.4 million) will be affected. CONCLUSION: Given the limitations of the data on which they are based, this report provides the best available prevalence estimates for arthritis and other rheumatic conditions overall, and for selected musculoskeletal disorders, in the US population. 相似文献
65.
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
66.
67.
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
68.
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
69.
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
70.
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