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121.
122.
Breast specimen radiography: evaluation of a compression device 总被引:1,自引:0,他引:1
The irregular shape and uneven tissue thickness of excised breast specimens makes radiographic evaluation difficult, especially when calcifications are not present. Xeroradiographs before and after compression of 20 separate excised breast specimens were compared, and 17 of the same specimens were compared after compression combined with immersion in water. Specimen compression improved visibility of the lesion on average in 88% of cases, and visibility was equal in 12%. Combined compression/immersion further improved visibility of the lesion on average in 37% of cases. More significantly, evaluation of the compressed specimen led to a change in interpretation of the radiographs in 45% of cases. Compression of the specimen in specimen radiography is recommended in all cases in which pre-biopsy localization is performed. 相似文献
123.
WA ARIFFIN S KARNANEEDI KE CHOO J NORMAH 《Journal of paediatrics and child health》1996,32(2):191-193
Between January 1985 and June 1992, the Paediatric Department of Hospital Universiti Sains Malaysia has diagnosed congenital dyserythropoietic anaemia in three children, two of whom were siblings. The age of onset ranged from 1 to 3 years. All of them became transfusion-dependent before the age of 4 months. One of them was successfully treated with bone marrow transplantation. 相似文献
124.
Pressure, or compressive, erosions of bone in various locations in patients with rheumatoid arthritis are described. Possible pathophysiologic mechanisms that account for the appearance and distribution of these erosions include osteopenia, soft-tissue laxity, soft-tissue pressure on bone, bone pressure on bone, and muscular forces. 相似文献
125.
L-Methylmalonyl-CoA mutase (MUT) is an adenosylcobalamin (AdoCbl)-
requiring mitochondrial matrix enzyme that catalyzes the isomerization of
L-methylmalonyl-CoA to succinyl-CoA. Inherited defects in the gene encoding
this enzyme result in the mut forms of methylmalonic acidemia. Expression
of mature human MUT cDNA in Escherichia coli at a post- induction
cultivation temperature of 12 degrees C, rather than 37 degrees C, led to
the folding of the majority of the synthesized protein to a soluble form,
with an activity of 0.2-0.3 U/mg protein in the cell-free extract, 10-15
times higher than that in human liver homogenate. Six missense mutations,
producing the amino acid changes G94V, Y231N, R369H, G623R, H678R and
G717V, were detected in MUT cDNA of patients suffering from the mut- form
of methylmalonic acidemia, resulting from defective AdoCbl binding. Two
(G623R and G717V) had been reported in other patients. Three (G94V, Y231N
and R369H) are the first changes in the NH2-terminal part of the enzyme
reported to cause the mut- phenotype. Enzymes with the mutations were
individually expressed, and their kinetic parameters were generally in
accord with published biochemical data from extracts of fibroblasts from
these patients. The mutations increased the K(m) for AdoCbl by 40- to
900-fold, while V(max) values varied from 0.2% to nearly 100% of that of
wild-type protein. In one case of a doubly heterozygous cell line, however,
neither of the constituent mutant enzymes had a K(m) corresponding to the
lower of the two estimated from the extract data. This finding may reflect
the natural occurrence of interallelic complementation in vivo in this cell
line.
相似文献
126.
Reference values for trabecular and cortical vertebral bone density in single and dual-energy quantitative computed tomography 总被引:4,自引:0,他引:4
W A Kalender D Felsenberg O Louis P Lopez E Klotz M Osteaux J Fraga 《European journal of radiology》1989,9(2):75-80
The validity of reference values for vertebral bone mineral density (BMD) reported in the literature has frequently been questioned. The introduction of dual-energy methods, new calibration systems, and automated image evaluation algorithms, has also made it necessary for us to re-evaluate BMD values in a normal population. We present patient selection criteria, CT measurement and evaluation protocols and results of single energy (SEQCT) and dual energy quantitative CT (DEQCT) for trabecular (tBMD) and cortical (cBMD) bone density in 135 males and 139 females. For SEQCT, tBMD loss rates of 1.7 and 1.8 mg/ml per year for males and females, respectively, were determined by linear regression. The respective DEQCT data show smaller decrements with age. Different statistical models for tBMD in females were tested; models based on a multiphase variation of tBMD yielded an improvement of the fit. For cBMD the percent rate of loss with age is much smaller than for tBMD; females showed a significantly higher loss rate than males, however. A comparison of our results with published data is included. 相似文献
127.
128.
One hundred two computed tomographic (CT) arthrograms of the shoulder were retrospectively reviewed and compared with conventional double-contrast arthrograms from 101 patients (24 females and 77 males aged 9-70 years). One- to 4-year follow-up was obtained in 84 patients, 40 of whom underwent open-shoulder surgery or arthroscopy. Morphology of the normal portions of each labrum was categorized according to length, width, and tip shape. Correlation between morphology and age was weak, but abnormal labra were more common in younger patients. Conventional radiography was more accurate for detecting bony glenoid margin fractures, but CT was more accurate for detecting Hill-Sach fractures. CT was also more reliable than conventional arthrography in the detection of rotator cuff tears. Hence, few if any conventional radiographs are necessary between contrast material injection and CT imaging. A reduction in the number of images obtained will result in decreased radiation dose, less cost, and shorter examination time without loss of diagnostic accuracy. 相似文献
129.
130.