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101.
The immunophenotypes of lymphoblasts from children with newly diagnosed T-cell acute lymphoid leukemia (T-ALL, n = 101) or T-cell non-Hodgkin lymphoma (T-NHL, n = 31) were analyzed to correlate stage of thymocyte differentiation with clinical features and outcome. The 67 boys and 34 girls with T-ALL were 1 month to 18 years old (median, 8 years) with leukocyte counts ranging from 2 to 810 x 10(9)/L (median, 55 x 10(9)/L). Eighteen of these patients were black, and 70 had a mediastinal mass. Twenty-six boys and five girls with a median age of 9 years (range, 1 to 20 years) had T-NHL. Seven of these patients were black, and 24 had a mediastinal mass. The distributions of thymocyte developmental stages (early [CD7+], intermediate [CD1+ and/or CD4+ and/or CD8+], and mature [CD3+]) in cases of T-ALL and T-NHL were significantly different: 34%, 43%, and 23% v 6%, 62%, and 32% (P = .02). A comparison of the patients' clinical features according to the maturational stage of thymocytes failed to disclose significant differences in the majority of characteristics studied. However, patients with mature-stage T-NHL, with or without the addition of subjects with mature-stage T-ALL, were less likely to have a mediastinal mass (P = .02 for both comparisons). Those with intermediate-stage T-cell malignancy (T-ALL and T-NHL combined) were the subgroup most likely to have a mediastinal mass (P = .01). Response to remission induction therapy was significantly worse in the T-ALL subgroup with an early-stage phenotype: a failure rate of 21% v 0% and 6% for the two more differentiated phenotypic subgroups (P = .007). Event-free survival was not affected by thymocyte maturational stage in cases of either T-ALL or T-NHL. Despite evidence of clinical heterogeneity among the maturational stages of T-cell malignancies in children, these developmental subdivisions do not appear to be critical determinants of outcome once remission is achieved. We conclude that such phenotypes need not be included in the stratification plans for clinical trials using common induction treatment.  相似文献   
102.
103.
Gelfand  DW; Chen  YM; Ott  DJ 《Radiology》1987,164(2):333-337
A systems approach was employed to improve results of the single-contrast barium enema examination for detection of colonic polyps. Improvements were made in each of the following areas: radiographic-fluoroscopic equipment, fluoroscopic-television images, screen-film combinations, barium suspensions, examination techniques, imaging sequences, and quality controls. Radiologic-endoscopic correlation was undertaken for 137 colonic polyps seen endoscopically in 91 patients. The average age of the patients was 69 years. The sensitivity of the single-contrast examination for detection of all polyps was 80%. Polyps 5-9 mm in size were detected with 66% sensitivity, while 94% of polyps 10 mm or larger were detected. The results indicate that the sensitivity of a suitably performed single-contrast barium enema examination may approach that of the double-contrast study for the detection of colonic polyps, even in an elderly and infirm patient population.  相似文献   
104.
Pathria  M; Sartoris  DJ; Resnick  D 《Radiology》1987,164(1):227-230
Sensitivity and specificity of lumbar spine radiography in the assessment of facet joint osteoarthritis were evaluated, with computed tomography (CT) as the standard. Two independent radiologists used a four-point scale to blindly grade facet joint osteoarthritis on oblique radiographs and transaxial CT scans obtained within an 8-month period in 50 consecutive patients with pain in the lower back. The L-3 to L-4, L-4 to L-5, and L-5 to S-1 facet joints were evaluated, and 68% appeared abnormal on CT scans, with 28% exhibiting moderate or severe disease. Interobserver agreement was high for conventional radiography (perfect agreement in 57% and agreement to within one grade in 39%) and still higher for CT (perfect in 63% and to within one grade in 35%). Receiver operating characteristic curve analysis indicated that oblique radiography was most accurate (55% sensitivity, 69% specificity) in distinguishing the presence from the absence of disease; in distinguishing absent or mild from moderate or severe disease, the specificity of oblique radiography was higher, at 94%, but its sensitivity was much lower, at 23%. Conventional radiography is a useful technique in screening for facet joint osteoarthritis but is insensitive compared with CT.  相似文献   
105.
Smythe  JS; Spring  FA; Gardner  B; Parsons  SF; Judson  PA; Anstee  DJ 《Blood》1995,85(10):2929-2936
This report describes the production and characterization of 13 rodent monoclonal antibodies to the human erythrocyte anion transport protein AE1 (syn. band 3). Eleven antibodies (4 murine and 7 rat) recognize epitopes dependent on the integrity of the third extracellular loop of the protein. Two antibodies (1 murine and 1 rat) recognize epitopes on the N-terminal cytoplasmic domain. Quantitative binding studies using radioiodinated IgG and Fab fragments of antibodies to extracellular epitopes on AE1 ranged from 77,000 to 313,000 (IgG) and from 241,000 to 772,000 (Fab) molecules bound at saturation. The results indicate that the epitopes recognized by different antibodies vary in their accessibility and suggest that there is heterogeneity in the organization of individual AE1 molecules in the red blood cell membrane. Quantitative binding studies on South East Asian ovalocytes using several antibodies to AE1 and an anti-Wrb show a marked reduction in the number of antibody molecules bound at saturation. These results are consistent with the existence of highly cooperative interactions between transmembrane domains of AE1 in normal erythrocytes and the disruption of these interactions in the variant AE1 found in South East Asian ovalocytes.  相似文献   
106.
107.
Visual development was studied in 10 very-low-birth-weight infants (less than 1500 g) with retinopathy of prematurity (ROP) stage 3+ who had been treated with cryocoagulation in both eyes. Binocular visual acuity (acuity cards method) and binocular visual fields (kinetic perimetry) were assessed repeatedly in the first year of life. At 12 months corrected age, visual acuity was normal in seven and impaired in three infants, who appeared to be severely myopic. Normal visual fields were found in eight infants at this age. The results indicate that cryotherapy in cases of ROP stage 3+ does not interfere with visual acuity development. The effect on visual field development needs further investigation.  相似文献   
108.
The effect of RU 486 (mifepristone), a potent antiprogestin, on the in-vitro fertilization of human oocytes was investigated. In 40 normal volunteer women requesting laparoscopic sterilization, follicle aspiration for oocyte recovery was attempted 34 h after the injection of 5000 i.u. human chorionic gonadotrophin (hCG). Twenty women were allocated to receive 100 mg RU 486 orally 1 h before the hCG injection, the remaining 20 women acted as controls. There was no significant difference in the cleavage rate of the oocytes after fertilization in vitro between the two groups (56% and 66% respectively). Also, the morphological characteristics of the cleaving oocytes and the concentrations of oestradiol, progesterone and androstenedione in the follicular fluid of the leading follicle did not differ significantly between the two groups. Since RU 486 was detected in substantial amounts in the follicular fluid specimens, these results suggest that progesterone is not critical for the final stages of human oocyte maturation.  相似文献   
109.
Association of imperforate anus and Hirschsprung's disease is rate, the incidence of both events occurring together would be one child out of every 25 million live births. A case of “cat-eye” syndrome with association of high imperforate anus and long segment Hirschsprung's disease is presented.  相似文献   
110.
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