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31.
Management of iron overload in the pediatric patient   总被引:2,自引:0,他引:2  
Iron overload is a major complication of long-term transfusion therapy. In the absence of treatment, the excessive iron causes diffuse organ damage, usually culminating in death from heart disease. Deferoxamine, an iron-chelating drug, removes tissue iron, prevents iron-induced organ dysfunction, and prolongs life. Proper administration of deferoxamine requires careful attention to dose, route and duration of administration, and compliance. Better chelators are needed but are unlikely to be available soon. Other methods for preventing or reducing iron accumulation involve alterations in the transfusion program or the blood product. Prevention of iron overload should improve the lives of patients with transfusion-dependent anemias and extend the usefulness of transfusion in chronic hematologic disorders.  相似文献   
32.
In this report, we examine the functional significance of the molecular microheterogeneity of alpha-fetoprotein (AFP). In doing so, we have taken the direct approach of purifying the naturally occurring isomeric forms of fetal-derived AFP using a preparative anion exchange column linked to an automated fast protein liquid chromatography (FPLC) system followed by parallel testing of each isolated molecular variant for in vitro immunoregulatory activity. The data obtained demonstrate the presence of seven distinct variants of AFP as defined by their retention volumes on FPLC elution profiles, by their pIs on analytical IEF gels, and by Western blot analysis. Molecular mass determination by SDS-PAGE showed each isomer to be equivalent in size to 69,000-dalton native unfractionated AFP molecules. All the immunosuppressive activity of AFP was localized to a single variant representing only 6% of the total composition of native AFP. The immunoregulating isomer termed AFP-1 was the least acidic of the seven isolated variants with a pI of 5.1 and displayed a sialic acid content of 1 mol/mol of protein. The inhibitory activity of AFP-1 could be readily measured on T cell-dependent antibody synthesis, Con A-induced stimulation of Lyt-1+23- thymocyte DNA synthesis, and lymphokine-activated NK cell activity. All other isomers were without effect in these test systems. The immunosuppressive AFP-1 isomer also displayed the strongest growth-promoting influence on cultured bone marrow lymphocytes. There was no correlation between functional activity and degree of expression of sialic acid residues on the AFP molecules. These findings demonstrate that the immunoregulating function of AFP is confined to a distinct and relatively small subpopulation of native AFP molecules and should therefore contribute to the resolution of outstanding questions regarding the structure/function relationship of this onco-fetal glycoprotein.  相似文献   
33.
To evaluate the use of pelvic ultrasonography in the diagnosis and management of female adolescents with pelvic inflammatory disease (PID), sonograms of 60 patients with PID were compared with those of 40 age-matched controls. Sonograms were evaluated for adnexal volume, adnexal adherence, uterine size, and the presence of cul-de-sac fluid. Eleven (19.3%) of the 57 patients with PID, in whom adequate sonograms were obtained, had tubo-ovarian abscesses; in seven of these patients, the abscesses were diagnosed ultrasonographically before suspected clinically. Even in those patients without tubo-ovarian abscesses, the mean (+/- SD) adnexal volume in the PID group was significantly larger than that of the control group (11.0 +/- 6.8 cm3 vs 5.2 +/- 2.7 cm,3 respectively). Adnexal adherence, uterine size, and the presence of cul-de-sac fluid were not useful in differentiating patients with PID from normal controls. Pelvic ultrasonography can be a useful adjunct in the diagnosis and management of PID in adolescents and may, in some instances, provide diagnoses in the absence of clinical findings.  相似文献   
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OBJECTIVES: To test a possible association between the educational level (EL), cognitive performance, and neuropsychiatric features in Parkinson disease (PD). BACKGROUND: An inverse association has been reported between EL and cognitive dysfunction in patients with senile dementia of Alzheimer type but it is yet unsettled whether education has a similar effect on cognition in PD. METHODS: Seventy-two PD patients (45 males, mean age 68.7+/-11.6 y) underwent a detailed neurologic examination, a battery of neuropsychologic tests, and questionnaires for the evaluation of psychosis, sleep disturbances, and depression. According to the number of educational years, patients were divided into 3 groups: low EL (0 to 8 y), (15 patients), intermediate EL (9 to 12 y) (28 patients), and high EL (>/=13 y) (29 patients). RESULTS: Patients with a higher EL had a better cognitive function and an association was found between the patients' EL and their scores in various neuropsychologic tests mainly those sensitive to frontal lobe dysfunction. Low education was associated with an increased risk for hallucinations and a trend for more depression, delusions, and sleep disturbances. CONCLUSIONS: The association between high educational attainment and the lower risk of cognitive dysfunction suggest that education might modulate cognitive performance in PD.  相似文献   
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37.
Cerebellar involvement in motor and non-motor sequence learning was examined with serial reaction time tasks (SRT). Our sample consisted of 8 children and adolescents who had undergone surgical removal of a benign posterior fossa tumor (PFT) during childhood. None of them had undergone chemotherapy or cranial radiation therapy (CRT). Ages ranged from 1-11 years at surgery and 9-17 years at testing. The children were tested not earlier than 2.5 years after surgery (M = 5.9 years), enabling brain plasticity and recovery of functions. Their performance was compared with a matched control sample. The PFT group was not impaired in the implicit learning of sequences, as reflected in their performance in blocks with a repeated sequence, both before and after a random block. However, in the perceptual task, their performance deteriorated more than that of the control group when a random block was introduced, suggesting that it was more difficult for the patients to respond flexibly or change their response set when encountering changing task demands. These results are in line with another study by our group on task switching with the same patients.  相似文献   
38.
Hemifacial hypertrophy (HFH) is rare and characterized by unilateral enlargement of the head and teeth. Hemifacial hypertrophy is classified as true HFH (THFH) with unilateral enlargement of the viscerocranium, and partial HFH (PHFH) in which not all structures are enlarged. We present a case of THFH and compare and contrast it with a case of PHFH. Hemifacial hypertrophy may cover a wide spectrum of defects or may involve only muscle or bone. Myohyperplasia, reported previously as a separate syndrome, may actually represent a forme fruste of PHFH or THFH. The PHFH patient lead a healthy, normal life without significant psychosocial problems and was reluctant to accept his deformity. Contrastingly, the THFH patient had significant social stigma and compromised health together with major aesthetic morbidity. Treatment planning in THFH is arduous and involves multiple modalities. Therefore, it is imperative to differentiate THFH and PHFH for better understanding and management of the condition.  相似文献   
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40.
Ciprofloxacin treatment of typhus   总被引:4,自引:0,他引:4  
M Eaton  M T Cohen  D R Shlim  B Innes 《JAMA》1989,262(6):772-773
  相似文献   
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