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81.
Eleven high risk fetuses between 32 and 37 menstrual weeks gestational age were examined by magnetic resonance (MR) imaging. Serial obstetrical sonograms, birth weights, and serial postnatal examinations were obtained in all subjects. Sagittal MR spin echo images obtained using TR = 0.5 sec and TE = 28 msec were useful for assessing subcutaneous fat. Prospective estimates of fetal fat stores correlated with neonatal outcome better than sonographic measurements of fetal growth parameters or actual birth weight. MR appears to be a safe and useful technique that offers information complementary to obstetrical sonography when IUGR is suspected.  相似文献   
82.
Marrow harvesting from normal donors   总被引:4,自引:2,他引:4  
The experience at a single institution in harvesting marrow for allogeneic transplantation on 1,270 occasions from 1,160 normal donors is presented in detail, together with an analysis of all the donor complications. Four donors were less than 2 years old, and the youngest was 6 1/2 months. No special difficulties were encountered with these young donors. Hospitalization time was three days or less for 99% of the procedures. Six donors had life-threatening complications; three of a cardiopulmonary and two of an infectious nature, and one cerebrovascular embolic episode. Significant operative site morbidity, usually transient neuropathies, occurred in ten procedures. Ten percent of the donations were associated with transient postoperative fever of unknown origin. Increasing donor age was associated with a reduction of the cellularity of the marrow harvest. The use of stored autologous blood permitted the avoidance of blood bank transfusion in 81% of males, 69% of females, and 50% of children. It was concluded that the procedure was associated with a very low risk of complication, but that the involvement of normal donors in such an operation justifies stringent monitoring.  相似文献   
83.
From 1990 to 1993 we performed a prospective study of busulfan (16 mg/kg) and cyclophosphamide (120 mg/kg) in 30 patients with refractory anemia (RA) undergoing related (n = 17) or unrelated (n = 13) donor marrow transplantation. Nineteen patients survive disease free (63% 3- year actuarial disease-free survival [DFS]) and no patient relapsed. These results were compared to those of 38 historical controls with RA treated with cyclophosphamide and total body irradiation, of whom 22 are disease-free survivors and 1 relapsed. After correcting for significant variables between the two treatment groups, we found no statistically significant difference in outcome based on preparative regimen. Combining data from these 68 patients plus 2 additional patients with RA treated before 1993 with busulfan and cyclophosphamide, we identified four variables independently associated with improved survival: younger age, shorter disease duration, lower neutrophil count pretransplant, and lower hematocrit pretransplant. We also found that 15 patients 40 to 55 years of age had a 46% 3-year actuarial DFS and 26 patients receiving unrelated or mismatched related donor marrow had a 50% 3-year actuarial DFS. We conclude that there does not appear to be any significant difference in outcome based on preparative regimen in this patient population. In addition, allogeneic bone marrow transplantation may be a reasonable approach to therapy of RA early after diagnosis. However, whether early intervention with transplantation prolongs survival over that expected without transplantation cannot be ascertained with certainty from available data.  相似文献   
84.
Many human globin-chain mutants contain amino acid replacements that result from single base changes in the corresponding globin gene. Using recombinants, the coding sequences of each of the alpha-, beta-, Ggamma- , and Agamma-globin genes have now been determined. Those sequences of DNA that are cleaved by a number of specific restriction endonucleases have been identified and accurately positioned. Mutations at these sequences abolish the restriction site, and therefore, the pattern of DNA fragments containing hybridizing globin-gene sequences is altered compared to DNA from normal persons. This allows the identification of one of a pair of cross-hybridizing human globin-gene sequences, as is shown here for the two alpha-globin, the two gamma-globin, and the delta- and beta-globin genes.  相似文献   
85.
86.
Titelbaum  DS; Hayward  JC; Zimmerman  RA 《Radiology》1989,173(3):663-667
Studies of 23 pediatric patients with pachygyriclike changes (PLCs) examined with computed tomography (CT) and magnetic resonance (MR) imaging were reviewed to determine topographic patterns and correlate them with various clinical syndromes and degrees of neurologic impairment. Three types of topographic distributions were identified: unilateral, diffuse, and bilateral nondiffuse (of which eight of 10 showed frontotemporal predominance). PLCs were an isolated finding in seven patients, were associated with various congenital syndromes in nine patients, and were associated with congenital infection in seven patients, six of whom showed marked white matter abnormalities. Although most patients had severe developmental delay, three with nondiffuse PLCs had less severe impairment, permitting less required care.  相似文献   
87.
Sixty-five multiply transfused patients with severe aplastic anemia were given cyclophosphamide followed by grafts anemia were given cyclophosphamide followed by grafts from HLA-identical siblings. The effect of the administration of viable donor buffy coat cells following the marrow inoculum was evaluated with regard to graft rejection and survival. Results in 43 patients so treated are presented along with those in 22 concurrent patients given marrow alone. Most patients given buffy coat had positive in vitro tests of sensitization indicating a high risk for graft rejection, while all but one of the patients given marrow alone had negative tests. Thirty of the 43 (70%) patients given marrow and buffy coat are alive between 10 and 61 mo (median 36) after grafting; 4 died after graft rejection and 6 with acute or chronic graft-versus-host disease (GVHD). Eleven of the 22 (50%) patients given marrow alone are alive between 29 and 65 mo (median 52); 7 died after graft rejection and 3 with GVHD. The addition of buffy coat cell infusions to the marrow inoculum reduced the risk of rejection and increased survival in the currently reported transfused patients when compared to patients grafted before 1976. However, there was an increased risk of chronic GVHD. Recipients of marrow from female donors survived slightly better (73%) than recipients of male marrow (58%).  相似文献   
88.
89.
To validate the level of olfactory performance of children, we tested 825 volunteers, aged 4–17 years, with an abbreviated form of our pediatric odorant identification task. The test consisted of sniffing and identifying five odorants (baby powder, bubble gum, candy cane, licorice and peach). Mean olfactory scores increased as a function of age, reaching a plateau of about 94–95% correct at 8 years of age. In general, girls out–performed boys. Physicians require a test instrument such as the one we have devised to allow them to diagnose olfactory dysfunction in children. The present task is particularly applicable in screening large numbers of children in clinics or schools because it can be administered easily and rapidly. Adult subjects with olfactory dysfunction also performed poorly on this odorant identification task designed for children. Therefore, we expect that our odorant identification task will also detect children with severe olfactory dysfunction.  相似文献   
90.
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