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排序方式: 共有384条查询结果,搜索用时 15 毫秒
71.
Magnetic resonance imaging and discography in the diagnosis of disc degeneration. A comparative study of 50 discs 总被引:8,自引:0,他引:8
M J Gibson J Buckley R Mawhinney R C Mulholland B S Worthington 《The Journal of bone and joint surgery. British volume》1986,68(3):369-373
The lumbar spines of 22 patients were examined for disc degeneration by magnetic resonance imaging (MRI) and by discography. The results from 50 intervertebral discs visualised by both techniques were independently assessed and graded on a five-point scale from normality to gross degeneration and then compared. In 44 discs the results agreed. Of the six discs which gave differing results, four discrepancies were due to observer error and two to incorrect placement of the discographic needle. MRI was shown to be more accurate than discography in the diagnosis of disc degeneration. It has several major advantages, which should make it the investigation of choice. 相似文献
72.
Incomplete antigenic cross-reactivity between platelets and megakaryocytes: relevance to ITP 总被引:6,自引:2,他引:4
Immune thrombocytopenias are usually associated with normal or increased numbers of megakaryocytes in the marrow. Therefore, the mechanism(s) responsible for the destruction of circulating platelets may not affect megakaryocytes in the same way. One of the possibilities which could account for the differential effect on the cells would be the development of antibodies to components of platelet membranes which are not exposed on the surface of all megakaryocytes. To investigate this possibility, a rabbit antiserum specific for mouse platelets was tested against fresh and cultured mouse megakaryocytes by indirect immunofluorescence. This antiserum cross-reacted with 46% of fresh murine megakaryocytes and 54% of cultured megakaryocytes. Phase- contrast microscopy revealed the reacting megakaryocytes to be fully granulated with irregular contours and in the process of releasing platelets. Nonreactive megakaryocytes demonstrated smooth contours and lacked morphological evidence of thrombocytopoiesis. Electron microscopy showed that only in megakaryocytes (MK) with an irregular contour had the demarcation membrane system (DMS) reached continuity with the plasma membrane. Ultrastructural analysis of megakaryocytes from patients with ITP showed approximately 25% to 50% of megakaryocytes without evidence of injury, whereas 50% to 75% had extensive damage. In undamaged cells, platelet territories had not yet reached the peripheral zone. The DMS of damaged megakaryocytes opened to the exterior elaborating platelets. The observations suggested that some platelet antibodies react only with megakaryocytes which have reached the stage of thrombocytopoiesis. Relevant target antigens may not be exposed on all megakaryocytes before cytoplasmic fragmentation occurs. 相似文献
73.
Smith TP; Vlodaver Z; Darcy MD; Hunter DW; Castaneda-Zuniga WR; Amplatz K 《Radiology》1987,163(1):271-272
Three commercial vessel dilators and a dilator of an improved design were tested during percutaneous catheterization in 16 mongrel dogs to evaluate arterial damage produced with their use. The results indicate that, although all dilators often produce arterial damage, the improved design produced much less damage. In addition, lesions were less severe overall. The dilator has been safely and successfully used in patients for percutaneous vessel catheterization for the past 30 years at the authors' institution. 相似文献
74.
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76.
目的定期随访评价ISOLA器械治疗小儿脊柱侧凸.方法41例小儿脊柱侧凸患儿,特发性脊柱侧凸32例,神经肌肉性脊柱侧凸5例,其他类型的脊柱侧凸4例,术前、术中、术后均摄X线片,记录Cobb角,顶椎的移位及旋转,躯干偏离中线程度.结果Cobb角术前平均为66°,术后1年为36°,术后2年为36°.1年后,所有患儿的脊柱均完全融合.顶椎的偏离改善了14mm.躯干偏离改善了5mm.特发性脊柱侧凸患儿1年后有基本的正常活动.术后4例出现并发症,1例深部感染,1例骶尾部褥疮,1例横钩脱落,1例L3椎弓根螺丝钉脱落.结论目前有多种后路器械治疗小儿脊柱侧凸.严格掌握手术指征及ISOLA的原理,该术式能获得较为满意的疗效. 相似文献
77.
PD Scheffer-Marinus TP Links WD Reitsma NM Drayer 《Acta paediatrica (Oslo, Norway : 1992)》1999,88(4):384-388
This study was conducted to analyse the effect of childhood-onset diabetes mellitus on adult height. The height at time of diagnosis of 35 children with insulin-dependent diabetes mellitus (IDDM) was compared with growth reference data. Predictions of the adult height were made at the time of diagnosis using the target height and the Tanner-Whitehouse II method. The adult height was compared with both the predicted values and the height of healthy adults. The height at time of diagnosis of the prepubertal children was increased compared with growth reference data, in contrast to pubertal children who had normal heights. Only the prepubertal boys were taller at time of diagnosis. The adult height of the prepubertal patients was taller than growth reference data. The mean adult height in all patients did not differ significantly from the predicted heights. In conclusion, the increased height at the start of IDDM in prepubertal children persists until adulthood. 相似文献
78.
Effects of short-term hypoxia on platelet counts of mice 总被引:3,自引:0,他引:3
Recent studies have shown that long-term hypoxia causes decreased platelet counts in mice and short-term hypoxia increased platelet counts. In an attempt to explain the mechanism that increases platelet counts of mice after exposure to short-term hypoxia, we measured platelet counts, total circulating platelet counts (TCPC), total circulating platelet masses (TCPM), percentages of 35S incorporation, and platelet sizes. Platelet counts, as well as TCPC and TCPM of mice, increased after 1-3 days of hypoxia, but these values were decreased after 6-7 days of hypoxia. Although platelet counts were increased in hypoxic mice, the percentage 35S incorporation into platelets and platelet sizes did not show a concurrent increase. After 6 days of hypoxia, average platelet diameters began to increase as platelet counts decreased. Splenic release did not account for the increase in platelet counts of mice after short-term hypoxia. It seems possible, therefore, that megakaryocytes "shed" platelets into the circulation in response to hypoxia. The platelets that enter the circulation in response to short-term hypoxia are smaller and incorporate less 35S than platelets that are produced in response to acute thrombocytopenia. 相似文献
79.
Miller TP; Grogan TM; Dahlberg S; Spier CM; Braziel RM; Banks PM; Foucar K; Kjeldsberg CR; Levy N; Nathwani BN 《Blood》1994,83(6):1460-1466
The growth fraction of tumors from patients with non-Hodgkin's lymphomas (NHL) has been shown to correlate with survival in retrospective studies. The growth fraction can be evaluated using immunohistochemical techniques employing the Ki-67 monoclonal antibody (MoAb) that marks a nuclear protein present in cycling cells. The purpose of this study was to evaluate the clinical utility of the Ki-67 MoAb for predicting survival. Using a prospective trial design in a multi-institutional cooperative trials group, the proliferative index, clinical outcome, and statistical correlations were independently assessed for previously untreated patients with advanced stages of intermediate- and high-grade histologies of NHL treated on Southwest Oncology Group study (SWOG 8516, Intergroup 0067). The proportion of Ki- 67-positive cells was determined on snap-frozen thin tissue sections. A proliferative index of 80% or greater, as determined from prior retrospective studies, identified a group of patients (18%) who had a poor outcome. Overall survival was significantly reduced in these patients with a high Ki-67-associated proliferative index compared with those with a low proliferative index (P = .001). One-year survival estimates were 82% (low proliferative index) versus 18% (high proliferative index). A multivariate regression analysis incorporating commonly used clinical prognostic features confirmed the independent effect of proliferation on survival (relative risk estimate 5.9; 95% confidence interval, 2.2, 16.1). The Ki-67 MoAb identifies a group of patients with rapidly fatal NHL for whom currently available chemotherapy is inadequate. 相似文献
80.
Van den Ende CH; Vliet Vlieland TP; Munneke M; Hazes JM 《Rheumatology (Oxford, England)》1998,37(6):677-687
The aim of this systematic review was to determine the effectiveness of
dynamic exercise therapy in improving joint mobility, muscle strength,
aerobic capacity and daily functioning in patients with rheumatoid
arthritis (RA). In addition, possible unwanted effects such as an increase
in pain, disease activity and radiological progression were studied. A
computer-aided search of the MEDLINE, Embase and SCISEARCH databases was
performed to identify controlled trials on the effect of exercise therapy.
Randomized trials were selected on the effect of dynamic exercise therapy
in RA patients with an exercise programme fulfilling the following
criteria: (a) intensity level such that heart rates exceeded 60% of maximal
heart rate during at least 20 min; (b) exercise frequency > or = 2 a
week; and (c) duration of intervention > or = 6 weeks. Two blinded
reviewers independently selected eligible studies, rated the methodological
quality and extracted data. Six out of 30 identified controlled trials met
the inclusion criteria. Four of the six included studies fulfilled > or
= 7/10 methodological criteria. Because of heterogeneity in outcome
measures, data could not be pooled. The results suggest that dynamic
exercise therapy is effective in increasing aerobic capacity and muscle
strength. No detrimental effects on disease activity and pain were
observed. The effects of dynamic exercise therapy on functional ability and
radiological progression are unclear. It is concluded that dynamic exercise
therapy has a positive effect on physical capacity. Research on the
long-term effect of dynamic exercise therapy on radiological progression
and functional ability is needed.
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