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51.
AP McCormack H Niki P Kiser AF Tencer BJ Sangeorzan 《Canadian Metallurgical Quarterly》1998,19(7):452-461
The effect of two different methods of reconstruction of flatfoot deformity and the role of the posterior tibial tendon on the contact characteristics of the hindfoot joints were quantified using pressure-sensitive film. Each of 10 cadaver feet was loaded quasi-statically by an axial compressive force to simulate varying loads. First, a specimen was tested intact, then it was tested after sectioning the spring ligament and loading the specimen cyclically to create one type of flatfoot deformity. It was then tested again after reconstructing the deformity. Reconstructions used were the Dillwyn-Evans procedure (bone graft in osteotomy of the calcaneus) or the calcaneocuboid distraction arthrodesis (CCDA). We found that surgically produced flatfoot deformity altered mainly the talonavicular joint, by decreasing its contact area. The Dillwyn-Evans method had less effect on the talonavicular joint (altering 2 of 6 measured parameters) than the CCDA (3 of 6) and more effect on the anteriomedial facet (altering 3 of 6 parameters) than the CCDA (1 of 6). The Dillwyn-Evans method had more effect on the posterior facet (altering 2 of 6 measured parameters) than the CCDA (1 of 6). Function of the posterior tibial tendon had no effect on contact characteristics of the hindfoot joints after either type of reconstruction. These findings are based on measurements using a quasi-statically-loaded foot model at three selected positions, and results may be different with dynamic loading. 相似文献
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A total of 88 Fallopian tubes from 44 patients was examined with hysterosalpingo contrast sonography (HyCoSy), hysterosalpingogram (HSG), and laparoscopic chromopertubation (LC) in order to assess their relative accuracy for measuring tubal patency. HyCoSy was done by transvaginal ultrasound and the contrast was SH U 454 (Echovist). The flow of multiple fractions of the contrast medium through each Fallopian tube was observed in real time in appropriate imaging planes by means of a transvaginal probe. Compared with laparoscopic results, we found a sensitivity of 85.2%, a specificity of 85.2%, a positive predictive value (PPV) of 71.9%, a negative predictive value (NPV) of 92.9% and concordance (HyCoSy/LC) of 85.2%, while the corresponding values for HSG were sensitivity = 85.2%, specificity = 83.6%, PPV = 69.7%, NPV = 92.7% and concordance (HSG/LC) of 84.1%. Compared with HSG results, HyCoSy obtained a co-positivity of 66.7%, a co-negativity of 81.8% and a concordance of 76.1%. In conclusion, HyCoSy with SH U 454 proved to be a reliable and safe modality for evaluating tubal patency; it is suitable as an outpatient diagnostic procedure to be used before more invasive procedures. 相似文献
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Orthopaedic disorders in children differ in type from those in adults: most frequent are congenital anomalies and disorders of growth and development. The special nature and relative rarity of these conditions justify the separate development of this branch of the discipline. Fractures almost always heal normally after closed reduction and immobilization in a plaster cast; fractures close to epiphyseal discs and in joints require special attention. Slipping of the upper femoral epiphysis necessitates surgical fixation of the epiphysis. Benign bone tumours occur relatively often and mostly require no surgical intervention. The prognosis of solid malignant bone tumours has improved since the introduction of (neo)adjuvant chemotherapy and limb-sparing surgery. In case of difference in leg length, the length of both legs is predicted with the aid of roentgenological measurements. Inhibition of the growth of the longer leg gives rise to fewer complications than lengthening of the short leg. The essence of the treatment of growth disorders due to abnormal ossification of the cartilage is to monitor the natural repair process and to intervene if permanent malformation threatens. 相似文献
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Myoglobin (Mb) has been believed to be absent generally from mammalian smooth muscle tissue. Examination of human rectal, uterine, bladder, colon, small intestine, arterial, and venous smooth muscle by immunohistochemical techniques shows that each of these tissues is immunopositive for both smooth muscle myosin and human Mb. Mb-specific primers were used for the polymerase chain reaction to generate cDNA from smooth muscle tissues. Southern hybridization with a Mb-specific probe gave a very strong signal with the cDNA from rectum, weaker signals from small intestine and uterus, a faint signal from colon, and no signal from bladder tissue. High performance liquid chromatography analysis coupled with sequence determination has shown that contaminating heme-binding serum albumin as well as hemoglobin in extracts of smooth muscle seriously compromise any heme-based or spectrophotometric assay of Mb. Combined affinity and size exclusion chromatography, however, provide the necessary resolution. The cDNA-derived amino acid sequence of human smooth muscle Mb was found to be identical to that of Mb from striated muscle. 相似文献
57.
A pilot-study was carried out on ten Dutch goat farms to see whether there is a relationship between farm management factors and the occurrence of toxoplasmosis. Questionnaires were used to collect information about farm management factors and blood samples were taken to determine the prevalence of toxoplasmosis on these farms. The mean prevalence was 47% (range 5-90%). The presence of kittens on a farm was a risk factor for a higher prevalence of toxoplasmosis. 相似文献
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ML Nochomovitz AF Dimarco JT Mortimer NS Cherniack 《Canadian Metallurgical Quarterly》1983,127(3):325-329
We studied in 10 supine anesthetized dogs diaphragm contraction produced by electrical activation with intramuscular electrodes surgically implanted in the ventral surface of the diaphragm and compared this with activation of the ipsilateral phrenic nerve (C5, 6, and 7) before it entered the thorax. Repetitive 40-Hz pulse trains with supramaximal current stimulus were used after hyperventilation of the animals to apnea. A single intramuscular electrode within 1 to 2 cm of the site of phrenic nerve entry into the diaphragm produced a mean transdiaphragmatic pressure of 12.0 cm H2O +/- 0.97 SE and mean tidal volume of 0.27 L +/- 0.04 SE. Mean values observed with phrenic nerve stimulation were not statistically different, and both electrode systems produced equivalent outward abdominal motion and upper rib cage paradox, as monitored by inductive plethysmography. There was no difference in gas exchange during stimulation with a single hemidiaphragm electrode and mechanical ventilation compared at the same tidal volume and respiratory rate. Blockade of neuromuscular transmission with curare eliminated intramuscular and phrenic nerve stimulation proportionately, suggesting that activation of the diaphragm is dependent in both cases on the phrenic nerve. This technique does not entail manipulation of the phrenic nerve and may have clinical application as an alternative technique for diaphragm pacing. 相似文献