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Brittenham GM  Nathan DG  Olivieri NF  Porter JB  Pippard M  Vichinsky EP  Weatherall DJ 《Blood》2003,101(12):5089-90; author reply 5090-1
  相似文献   
23.
Ten haemophilia centres in northern Europe have pooled data on 202 haemophilic children who were infected with HIV between 1979 and 1986. All cases were under 16 years of age on 1 July 1985. The age at infection ranged from 1-15 years. Thirty seven cases (18%) had progressed to AIDS by 1 July 1991 and 15 of these have died. Persistent generalised lymphadenopathy has been noted in 102 patients of whom 18 (17%) have developed AIDS. Twenty three of the remaining patients (23%) have not. CD4+ T cell counts have fallen steadily. Of 36 patients who have had shingles since seroconversion, 19 (53%) had counts below 0.2 x 10(9)/l. Thirty five out of 145 patients without shingles (24%) had similar values. The mean IgA concentration in patients with CD4+ T cell counts above 0.5 x 10(9)/l was 2.38 g/l, between 0.2 and 0.5 was 3.07 g/l, and in those with CD4+ T cell counts below 0.2 x 10(9)/l the mean IgA concentration was 4.58 g/l. Treatment patterns have altered between 1989 and 1991, with increased use of zidovudine in patients without AIDS and a marked increase in primary prophylaxis against pneumocystis pneumonia. This has been associated with a decline in the incidence of pneumocystis as an indicator disease in new AIDS cases from 56% in 1989 to 20% in 1991. These observations indicate that persistent generalised lymphadenopathy does not worsen the outlook, but shingles does. Rising IgA concentrations are markers for disease progression. Modern prophylactic regimens are delaying the onset of indicator disease, but CD4 values continue to fall steadily.  相似文献   
24.
PURPOSE: To compare the rates of perioperative morbidity of patients with sickle cell anemia who were randomly assigned to 2 preoperative transfusion regimens and to identify predisposing factors for perioperative complications. PATIENTS AND METHODS: Investigators at 36 centers enrolled 118 patients who were scheduled to have elective surgery and agreed to randomization between 2 preoperative transfusion regimens. Forty-seven subjects were enrolled but not randomized, including 20 who were not transfused before surgery. Perioperative management was based on a prescribed care plan. RESULTS: Tonsillectomy and/or adenoidectomy (TA) were performed on 136 persons, and 29 had myringotomy as their primary procedure. There were no differences in the frequency of complications between the randomized groups. The serious, non-transfusion complication rates for randomized patients were 32% (34 of 107) for TA and 36% (4 of 11) for myringotomy. A history of pulmonary disease was a predictor of postoperative sickle cell-related events for patients undergoing TA surgery. CONCLUSIONS: The more intensive transfusion regimen did not result in fewer perioperative complications. The high frequency of complications emphasizes the need for anticipatory management of persons undergoing TA. A history of pulmonary disease identifies patients at increased risk for sickle cell-related events after TA surgery. Patients undergoing myringotomy have a low frequency of sickle cell-related events but a significant frequency of other serious perioperative complications.  相似文献   
25.
Transneuronal degeneration of retinal ganglion cells was directly demonstrated in a patient who had unilateral removal of the striate cortex forty years prior to necropsy. For comparison, another case is presented showing anterograde transneuronal atrophy forty years after enucleation of one eye.  相似文献   
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An increasing number of Southeast Asian immigrants have come to North America. Physicians who care for this population should be aware of the high prevalence of hematologic disorders and develop an approach to their diagnosis and management. Malaria and the hematologic sequelae, glucose-6-phophate dehydrogenase deficiency, the thalassemia syndromes, Southeast Asian ovalocytosis, visceral leishmaniasis, HIV infection, and iron-deficiency anemia, all of which may pertain to these patients, are reviewed in this article.  相似文献   
28.
OBJECTIVES: To examine the body composition of children and adolescents with sickle cell disease (SCD) using bioelectrical impedance analysis and to determine if the impedance parameters resistance, reactance, and phase angle are able to distinguish between subjects with SCD and age- and gender matched controls. STUDY DESIGN: Total body resistance and reactance were obtained for a total of 53 subjects with SCD (27 male and 26 female) between 10 and 18 years of age and 49 control subjects (23 male and 26 female). The fat-free mass, body cell mass, phase angle, and capacitance were also determined. Group comparisons were made using the 2-sample t test. RESULTS: Male subjects with SCD had significantly lower fat-free mass (37.5 +/- 8.8 vs 43.9 +/- 12.3 kg, P =.04), body cell mass (17.4 +/- 4.3 vs 21.7 +/- 5.8 kg,P =.005), and body fat (3.7 +/- 2.6 vs 6.6 +/- 4.7 kg, P =.008) compared with controls. No significant differences in any body composition components were found for the female subjects. Both male and female subjects had significantly lower phase angle measurements (P <.001 and.006, respectively) than their respective controls, indicating possible alterations in cell membrane properties because of an imbalance in membrane composition or function. CONCLUSIONS: Bioelectrical impedance analysis can be used to determine body composition differences in children with SCD. The phase angle may provide a useful method to monitor the efficacy of therapeutic interventions in patients with SCD.  相似文献   
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Kinnison  ML; Powe  NR; Steinberg  EP 《Radiology》1989,170(2):381-389
The authors reviewed 100 randomized controlled trials (RCTs) conducted in humans to compare safety or efficacy of new low-osmolality contrast media (LOM) with that of high-osmolality contrast media (HOM). Findings of the 43 RCTs judged to be of the highest quality suggest that the efficacy of LOM in imaging is equal or superior to that of HOM for all routes of administration. Heat sensation occurred less often with LOM for all routes and pain occurred less often with LOM for intraarterial routes. No differences were seen in nephrotoxicity or in frequency of nausea, vomiting, urticaria, bronchospasm, laboratory test abnormalities, or neurologic events. Greater cardiovascular changes were seen with HOM, including increased or decreased heart rate, increased left ventricular end-diastolic pressure, decreased systolic pressure, and QT prolongation, depending on route of administration. To demonstrate whether a reduction in clinically significant adverse outcomes truly occurs with LOM, trials will need to enlist larger numbers of patients and employ appropriate outcome measures. Future trials should stratify patients according to their risk of adverse reactions to provide better information about benefits of LOM in low- versus high-risk patients.  相似文献   
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