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排序方式: 共有494条查询结果,搜索用时 15 毫秒
1.
Long-term survivorship analysis of cruciate-sparing versus cruciate-sacrificing knee prostheses using meniscal bearings 总被引:6,自引:0,他引:6
A comprehensive, interchangeable, low-contact-stress, mobile-bearing knee prosthesis system was developed and used over a 12-year period with both cemented and cementless fixation. Individual components of the system included a bicruciate-retaining meniscal bearing, a posterior cruciate-retaining meniscal bearing, and a cruciate-sacrificing, rotating-platform tibial component mated to the same femoral and rotating patellar components. Survivorship analysis of each implant type was performed to identify specific failure modes and trends for long-term survival of the implants in a wide variety of primary knee arthroplasties. Clinically, there were 46 prostheses of the bicruciate type followed for up to 12 years, 57 prostheses of the posterior-cruciate type followed for up to six years, and 108 prostheses of the rotating-platform type followed for up to ten years. All knees in this study had rotating-bearing patellar prostheses. Cumulative survivorship analysis using an end point of implant revision or a poor knee score revealed a small early failure rate of each implant in the first three years, associated with technical positioning or undersizing errors. This study indicates a predictable long-term survival of both cruciate-retaining and cruciate-sacrificing mobile-bearing knee prostheses as well as rotating-bearing patellar prostheses when used in primary knee arthroplasties that minimized technical errors of insertion. 相似文献
2.
Hillmann JS; Mesgarzadeh M; Revesz G; Bonakdarpour A; Clancy M; Betz RR 《Radiology》1987,165(3):769-773
Proximal femoral focal deficiency, an uncommon congenital anomaly, necessitates early radiologic classification for surgical planning and treatment. Objective radiographic criteria, including femoral length index, acetabular depth index, acetabular angle index, and shape of the proximal femur were determined in 49 patients before cartilaginous ossification of the femoral capital epiphysis; final classification was based on follow-up radiographs or findings at arthrography or surgery. These parameters were analyzed to determine the accuracy and contributions of each in classification. Correct classification into one of three groups was possible in 86% of cases with use of three of the parameters: femoral length index, acetabular depth index, and shape of the proximal femur. The acetabular angle was found to contribute insignificantly to classification. Magnetic resonance imaging, used in only one case, depicted the nonossified cartilaginous femoral capital epiphysis, thus obviating the need for invasive diagnostic procedures and facilitating early classification. 相似文献
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6.
The New Jersey Low-Contact-Stress Knee Replacement System: biomechanical rationale and review of the first 123 cemented cases 总被引:1,自引:0,他引:1
F F Buechel M J Pappas 《Archives of orthopaedic and traumatic surgery. Archiv für orthop?dische und Unfall-Chirurgie》1986,105(4):197-204
A mobile-bearing element, metal-backed, interchangeable knee replacement system has been designed to combine low constraint forces with low contact stresses (LCS), allowing nearly normal joint articulation and loading as well as long-term wear resistance of the implants. The system is versatile, including a large number of component options in variable sizes, and it may be used in both primary and revision arthroplasties. The overall results in the first 123 cemented cases (97 patients) with 2- to 7-year follow-up (average 3.7 years) were good to excellent in 88.6%, fair in 3.3%, and poor in 8.1%. Fair and poor results were seen predominantly in multiply operated and implant revision cases. The best results were noted in primary cases, 97.4% of which had good to excellent results. There have been no mechanical implant failures and no meniscal bearing dislocations in this series. Pain relief and restoration of function have been very gratifying with this system. 相似文献
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8.
Life expectancy in British Marfan syndrome populations 总被引:2,自引:0,他引:2
JR Gray AB Bridges RR West L. McLeish AG Stuart JCS Dean MEM Porteous M. Boxer SJ Davies 《Clinical genetics》1998,54(2):124-128
A total of 206 patients with Marfan syndrome were ascertained throughout genetic clinics in Wales and Scotland during the period 1970–1990. There were 45 deaths representing 22% of the cohort. Mean age at death was 45.3 ± 16.5 years. 50% median cumulative survival in the total cohort (n = 206) was 53 years for males and 72 years for females. Multivariate analysis confirmed severity as the best independent indicator of survival. These findings and survival curves will assist in the counselling of British families and individuals with Marfan syndrome. 相似文献
9.
10.
Human MSH2 binds to trinucleotide repeat DNA structures associated with neurodegenerative diseases 总被引:5,自引:5,他引:5
The expansion of trinucleotide repeat sequences is associated with several
neurodegenerative diseases. The mechanism of this expansion is unknown but
may involve slipped-strand structures where adjacent rather than perfect
complementary sequences of a trinucleotide repeat become paired. Here, we
have studied the interaction of the human mismatch repair protein MSH2 with
slipped-strand structures formed from a triplet repeat sequence in order to
address the possible role of MSH2 in trinucleotide expansion. Genomic
clones of the myotonic dystrophy locus containing disease-relevant lengths
of (CTG)n x (CAG)n triplet repeats were examined. We have constructed two
types of slipped-strand structures by annealing complementary strands of
DNA containing: (i) equal numbers of trinucleotide repeats (homoduplex
slipped structures or S-DNA) or (ii) different numbers of repeats
(heteroduplex slipped intermediates or SI-DNA). SI-DNAs having an excess of
either CTG or CAG repeats were structurally distinct and could be separated
electrophoretically and studied individually. Using a band-shift assay, the
MSH2 was shown to bind to both S-DNA and SI-DNA in a structure- specific
manner. The affinity of MSH2 increased with the length of the repeat
sequence. Furthermore, MSH2 bound preferentially to looped-out CAG repeat
sequences, implicating a strand asymmetry in MSH2 recognition. Our results
are consistent with the idea that MSH2 may participate in trinucleotide
repeat expansion via its role in repair and/or recombination.
相似文献