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991.
We measured broad-band ultrasound attenuation (BUA) in the calcaneum using the prototype Paediatric Contact Ultrasound Bone Analyser (CUBA) and total body bone mineral density (TBBMD) using dual-energy X-ray absorptiometry (DXA) (Hologic QDR-1000W) in 58, 7 17-year-old healthy children and adolescents. Calcaneal BUA was significantly related to TBBMD ( r = 0.74, p < 0.001), and both the calcaneal BUA and TBBMD were significantly correlated with age and body weight. We conclude that calcaneal BUA reflects bone mineral density (BMD) in healthy children and adolescents; however, BMD measured by CUBA appears to be less sensitive than that measured by DXA. Since BUA reflects structural properties of bone, as well as density, it may complement radiological techniques of bone density measurement in the assessment of paediatric conditions associated with fracture risk.  相似文献   
992.
Two very rare cases of splenic trauma following high translumbar aortography are described. Two types of clinical picture are observed : severe intraperitoneal hemorrhage, subcapsular and then intraperitoneal, from rupture of the spleen, and septic peritonitis following rupture of an intra- and perisplenic abscess. The authors review the frequency, mechanism, and prevention of complications following translumbar aortic puncture.  相似文献   
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Tumeh  SS; Benson  C; Nagel  JS; English  RJ; Holman  BL 《Radiology》1987,164(2):353-356
The roles of single-photon emission computed tomography (SPECT) and planar imaging with technetium-99m-labeled red blood cells in the diagnosis of cavernous hemangioma of the liver were evaluated. The study group consisted of 26 consecutive patients referred for evaluation of liver lesions. A total of 23 cavernous hemangiomas were found, all of which showed decreased or normal flow and delayed uptake of the radiotracer. SPECT demonstrated 13 hemangiomas that were not detected with planar imaging; both modalities demonstrated the other ten lesions. Lesions that were not cavernous hemangiomas showed either normal (n = 6) or increased (n = 4) flow; none had delayed increased uptake on either planar or SPECT images. SPECT with labeled red blood cells is an accurate method for the detection of cavernous hemangiomas of the liver and is more sensitive than planar imaging in depicting small lesions.  相似文献   
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This report describes the conversion of a murine pituitary thyrotropic tumor (MGH 101) to a pure alpha-subunit-secreting tumor (MGH 101A) during a 6-yr period of serial transplantation. MGH 101 was a thyrotropic tumor originating from a hypothyroid mouse pituitary, growing only in hypothyroid hosts, and secreting large quantities of intact TSH and free alpha-subunit. Between the fourth and ninth transplantation generations, tumor TSH secretion declined progressively by at least 500-fold, to undetectable levels. In contrast, tumor secretion of free alpha-subunit decreased only 10-fold, and has since remained stable for nine transplantation generations. During the conversion to pure alpha-subunit secretion, MGH 101A exhibited growth in euthyroid as well as hypothyroid hosts, and increased its growth rate 2 to 3-fold. In contrast, the conventional thyrotropic tumor TtT 97 has maintained its secretion of both intact TSH and free alpha-subunit, its dependence on a hypothyroid environment, and its slower growth rate for nine generations. Gel chromatography of the media from tumor cell cultures confirmed that MGH 101A secreted only the free alpha-subunit, whereas TtT 97 secreted immunoactive TSH, TSH beta, and free alpha-subunit which eluted as separate peaks. We conclude that a dependent thyrotropic tumor has spontaneously developed into a pure alpha-subunit-secreting tumor which is independent of host thyroid function for its growth and alpha-subunit production.  相似文献   
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