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排序方式: 共有2065条查询结果,搜索用时 31 毫秒
1.
2.
Extensor mechanism complications following 281 knee arthroplasties that included patellar resurfacing, performed by two surgeons in one hospital over a 6-year period, were reviewed. The mean follow-up period was 42 months. There were 28 (10%) extensor mechanism complications: 3 quadriceps tendon ruptures, 5 patellar fractures, 4 patellar tendon ruptures, 11 recurring patellar subluxations, 4 cases of patellar pain, and 1 malrotated patella. Nine (3%) required further surgery. Surgical technique may have contributed to the tendon ruptures; patellar fractures occurred mainly in patients who had rheumatoid arthritis. Patients with patellar subluxation had abnormal preoperative valgus deformities of their knees and presented with this subluxation problem an average of 4 months after surgery, but it appeared to cause them less discomfort with time. Patellar resurfacing as part of a knee arthroplasty procedure is recommended but should be performed with care to the integrity and vasculature of the extensor mechanism. 相似文献
3.
T H Bourne D Jurkovic J Waterstone S Campbell W P Collins 《Ultrasound in obstetrics & gynecology》1991,1(1):53-59
Transvaginal ultrasonography with color flow mapping has been used to study changes in intrafollicular blood flow and morphology during follicular rupture and presumed ovulation in one human volunteer. Detailed monitoring started on day 11 of the menstrual cycle and the follicle began to rupture at 14.30 on day 13. This event was preceded by a defined rise and peak in the level of immunoreactive serum luteinizing hormone (LH) by 42 h and 17 h 20 min, respectively. Blood vessels were clearly visible in the inner ring of the follicle (the granulosa layer) at the time of the LH peak and part of the granulosa (probably containing the oocyte) started to detach before the follicle ruptured. The maximum value for the peak blood velocity in the inner vessels was observed 10 s after the start of follicular rupture and there was a concurrent increase in the impedance to blood flow, as reflected by the resistance index and the pulsatility index. The follicle took 14 min 29 s to empty and the corpus haemorrhagicum started to form about 1 min later. These preliminary data suggest that intrafollicular angiogenesis and changes in blood flow can be monitored by a relatively non-invasive technique. Changes in vascularity might be used to predict imminent ovulation and could possibly be identified or modified biochemically to help achieve or avoid a pregnancy. 相似文献
4.
S E Wilson W M Bourne P C O'Brien R F Brubaker 《American journal of ophthalmology》1988,106(3):270-278
Using a two-dimensional scanning fluorophotometer, we studied 50 subjects with symmetric ocular involvement of Fuchs' dystrophy without epithelial edema. Twenty-six subjects with confluent or nearly confluent cornea gutata with increased corneal thickness and 24 subjects with mild to moderate cornea guttata with normal corneal thickness were compared to normal control subjects. There were no statistically significant differences in endothelial permeability between the three groups. Corneal thickness was significantly increased in the subjects with confluent to nearly confluent guttae, however. These results suggest that endothelial pump function may be affected in subjects with advanced cornea guttata with stromal edema. 相似文献
5.
R W Arnold G B Stickler W M Bourne J F Mellinger 《Journal of pediatric ophthalmology and strabismus》1987,24(3):151-155
A case with ocular (corneal crystals and retinal pigment epithelial mottling), muscle (oropharyngeal and hand weakness and atrophy), and renal (proteinuria and hypertension) abnormalities is described. We believe that this represents a previously unrecognized syndrome. 相似文献
6.
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
7.
8.
R B Bourne H Bitar P R Andreae L M Martin J B Finlay F Marquis 《Canadian journal of surgery》1988,31(1):43-45
Absorbable sutures are initially equal or superior to nonabsorbable sutures in terms of tensile strength but are absorbed at variable rates by the action of hydrolysis. This study demonstrated that the in-vivo half-life tensile strength of the braided absorbable sutures polyglycolic acid (Dexon Plus) and polyglactin 910 (Vicryl) is 2 weeks, whereas those of the monofilament absorbable sutures polyglyconate (Maxon) and polydioxanone (PDS) are 3 and 6 weeks respectively. The addition of a single hitch or six knots reduced the in-vitro tensile strength by 30% to 35%. Polyglyconate (Maxon) suture demonstrated the best in-vitro knot security. 相似文献
9.
10.
T. K. Moroz J. B. Finlay C. H. Rorabeck R. B. Bourne 《Medical & biological engineering & computing》1988,26(3):271-276
Detailed data of the stability of external fixation devices are needed by the orthopaedic surgeon to predict successful healing
of a fracture. The stability (rigidity, yield and failure criteria) of four half-frame configurations (single, stacked, double
and delta) of the original Hoffmann and AO tubular frame have been analysed under four loading conditions: axial compression,
torsion, and both AP- and ML-bending. Overall the two systems' rigidities were the same between similar configurations. Both
systems' single half-frames were particularly weak; however, as the number of components (rods, pins, clamps, couplings) on
the frame increased, the rigidity of the frame increased. The difference in performance between the two systems lies in their
yield and failure characteristics. The AO system exhibited excellent failure criteria in all modes of loading, i.e. no configuration
failed within the test limits, whereas most Hoffman frames yielded and failed at low loads. 相似文献