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41.
BACKGROUND: Clinical manifestations and course of sickle-cell anemia are variable. Knowledge about the factors, possibly geographic, that influence prognosis are still scanty. POPULATION AND METHODS: Data of hospitalization and management of children with sickle-cell disease were studied during two years (1992-1993) in the Pediatric Unit of Libreville Hospital. They concerned 205 admissions of 171 children and 131 outpatients. RESULTS: The main causes of hospitalization were: acute anemia (36 cases before the age of 5 years); painful crisis whose frequency increased with age (23% before 5 years, 35% between 5 and 10, 42% after 10 years); infections, essentially pulmonary occurring early, and bone infections at any age. Eight children died (because a complication of their disease). Among the 131 outpatients, half were detected because pyrexia, anemia and/or more often "hand-foot syndrome". More than 60% had hepatomegaly, one third still had splenomegaly after five years of age and more than one third was icteric. More than half children older than ten years had growth disorders. Mean hemoglobin level was 7 g/dL. 21 of the 83 tested children for HBsAg were positive and only one out of 79 was positive for HIV. CONCLUSIONS: Clinical manifestations and course of sickle-cell anemia in our patients are similar to those reported in Congolese children. Genetic and environmental factors may be responsible for differences with children from other, in particular French, cohorts.  相似文献   
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PURPOSE: To identify patients with lymphoma at risk for tumor lysis after chemotherapy. PATIENTS AND METHODS: The case records of 102 patients receiving combination chemotherapy for non-Hodgkin's lymphoma (intermediate to high-grade histology) were reviewed. Patients were considered to have "laboratory tumor lysis" if two of the following metabolic changes occurred within 4 days of treatment: a 25% increase in the serum phosphate, potassium, uric acid, or urea nitrogen concentrations, or a 25% decline in the serum calcium concentration. "Clinical tumor lysis" was defined as laboratory tumor lysis plus one of the following: a serum potassium level greater than 6 mmol/L, a creatinine level greater than 221 mumol/L, or a calcium level less than 1.5 mmol/L, the development of a life-threatening arrhythmia, or sudden death. RESULTS: Laboratory tumor lysis occurred in 42% of patients and clinical tumor lysis in 6%. There was no statistical difference in the frequency of either tumor lysis syndrome among lymphoma subgroups. Clinical tumor lysis occurred more frequently in patients with pretreatment renal insufficiency (serum creatinine level greater than 132 mumol/L) than in patients with normal renal function (36% versus 2%; p = 0.01). The development of azotemia correlated with high pretreatment serum lactate dehydrogenase concentrations (p < 0.01; r2 = 0.11). CONCLUSION: Clinically significant tumor lysis is a rare occurrence in patients with lymphoma when they are receiving allopurinol. However, tumor lysis can occur in patients with all types of moderate to high-grade non-Hodgkin's lymphoma. Patients with a high serum lactate dehydrogenase level or renal insufficiency are at increased risk for metabolic complications after chemotherapy and should be closely monitored.  相似文献   
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Disc disease is benign and not life threatening. Its long-term prognosis is uncertain, and spontaneous recoveries are common. The decision to perform surgery thus carries with it a heavy responsibility to provide safe treatment. "Good safe surgical technique" is essential, but it is much more than a well-rehearsed routine procedure. From preoperative evaluation to surgery to postoperative care, the surgeon must look ahead to problems that might arise. Where anticipated risks cannot be avoided, they should be minimized, and when adverse events occur, active recognition will lead to early and accurate management.  相似文献   
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When small, unilamellar lipid vesicles containing a high concentration of the fluorescent dye 6-carboxyfluorescein are incubated with either frog retinas or human lymphocytes, fluroescence distributes widely throughout each cell. Since "self-quenching" largely prevents the dye from fluorescing as long as it remains sequestered in vesicles, it is clear that a considerable amount of dye is released from the vesicles and diluted into the much larger volume of the cell.  相似文献   
45.
The existence of a psoriasis susceptibility locus, PSORS1 (HUGO/GDB-approved symbol), in or near the HLA region of chromosome 6 is strongly supported by a lod score analysis of HLA-B and psoriasis in 97 families from 16 published datasets. Families included in the dataset represent all the psoriasis families with usable HLA data that we could find in the published literature through May 1997. The recombination fraction between PSORS1 and HLA-B is estimated to be at or near 0.00, with a maximum two-point lod score of 23.7, assuming a dominant mode of inheritance with low (20%) penetrance at the PSORS1 locus. Although these families are geographically and ethnically diverse, there is no evidence for linkage heterogeneity at the HLA-linked locus in this analysis. We also conclude that the HLA-B17 allele, which is strongly associated with psoriasis, is unlikely itself to contribute directly to psoriasis susceptibility; rather, the HLA-B locus is probably tightly linked to the PSORS1 locus. Finally, we raise the possibility of a two-locus/heterogeneity model as one way to reconcile several findings in the literature.  相似文献   
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Gag gene mutants of human immunodeficiency virus type 1 (HIV-1) were analyzed for their potentials of inhibiting the replication of wild-type (wt) HIV-2, the second AIDS virus, in a single-round of viral replication. Of twenty-two HIV-1 gag mutants examined, seven were found to efficiently interfere with the replication of wt HIV-2. Some mutants, which can suppress the replication of wt HIV-1, did not show this inhibitory effect. These mutants were defective at the late phase of viral replication. A mutant designated NL-C1a was demonstrated to be very effective against the replication of HIV-1 and HIV-2 in monocytic cells as well as in lymphocytic cells.  相似文献   
48.
Increased mobilization of non-esterified fatty acids (NEFA) from visceral as opposed to peripheral fat depots can lead to metabolic disturbances because of the direct portal link between visceral fat and the liver. Compared with peripheral fat, visceral fat shows a decreased response to insulin. The mechanisms behind these site variations were investigated by comparing insulin action on NEFA metabolism with insulin receptor signal transduction through the insulin receptor substrate-1 (IRS-1) pathway in omental (visceral) and subcutaneous human fat obtained during elective surgery. Insulin inhibited lipolysis and stimulated NEFA re-esterification. This was counteracted by wortmannin, an inhibitor of phosphaditylinositol (PI) 3-kinase. The effects of insulin on antilipolysis and NEFA re-esterification were greatly reduced in omental fat cells. Insulin receptor binding capacity, mRNA and protein expression did not differ between the cell types. Insulin was four times more effective in stimulating tyrosine phosphorylation of the insulin receptor in subcutaneous fat cells (p < 0.001). Similarly, insulin was two to three times more effective in stimulating tyrosine phosphorylation of IRS-1 in subcutaneous fat cells (p < 0.01). This finding could be explained by finding that IRS-1 protein expression was reduced by 50 +/- 8% in omental fat cells (p < 0.01). In omental fat cells, maximum insulin-stimulated association of the p85 kDa subunit of PI 3-kinase to phosphotyrosine proteins and phosphotyrosine associated PI 3-kinase activity were both reduced by 50% (p < 0.05 or better). Thus, the ability of insulin to induce antilipolysis and stimulate NEFA re-esterification is reduced in visceral adipocytes. This reduction can be explained by reduced insulin receptor autophosphorylation and signal transduction through an IRS-1 associated PI 3-kinase pathway in visceral adipocytes.  相似文献   
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