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381.
OBJECTIVES: To assess the impact of HIV-related immunodeficiency and antiretroviral treatment on the occurrence and evolution of abnormal Papanicolaou tests. STUDY DESIGN: Cohort of 485 HIV-infected women with a known date of infection, enrolled during May 1993-April 1998 in 23 centres (gynaecology, infectious disease or STD clinics, or drug treatment centres) in 12 European countries; in 21 centres, follow-up was performed every 6 months (median follow-up: 2 years). METHODS: Human papillomavirus (HPV) was detected at inclusion by Southern blot and PCR. The prevalence of squamous intraepithelial lesions (SIL), the incidence of SIL and regression from low-grade SIL were studied according to CD4 count after controlling for HPV detection results. RESULTS: Compared with women with CD4 cell counts > 500 x 10(6)/l, women with CD4 cell counts < 200 x 10(6)/l had a twofold increase in both prevalence and incidence of SIL and in non-regression from untreated low-grade SIL; in addition, these women had a lower response rate to treatment of high-grade cervical intraepithelial neoplasia. The increase in SIL incidence associated with a low CD4 cell count was significant in women not receiving antiretroviral treatment (relative risk, CD4 cell count 200-499 x 10(6)/l, 1.9; CD4 cell count < 200 x 10(6)/l, 2.9; CD4 cell count > 500 x 10(6)/l, reference), whereas it was less marked and not statistically significant in treated women. CONCLUSIONS: Severe HIV-related immunodeficiency strongly increases the risk of occurrence of SIL; antiretroviral treatment may reduce this risk, probably by restoring or at least preserving immune function.  相似文献   
382.
Several life-threatening complications of the common disorder sickle cell disease require management with red blood cell transfusions and, hence, long-term iron-chelating therapy. The efficacy of the oral iron chelator 1,2-dimethyl-3-hydroxypyrid-4-one (L1) has not previously been determined in patients with sickle cell disease. We compared the efficacy of L1 to that of standard-dose subcutaneous deferoxamine in four regularly transfused patients with homozygous sickle cell disease, who had evidence of severe iron overload and a history of poor compliance with deferoxamine. Determination of 24-hour urinary iron excretion conducted over 5 days immediately after transfusion showed that the mean daily urinary iron excretion induced by L1 at 75 mg/kg/d (0.48 +/- 0.23 mg/kg) was equivalent to that induced by deferoxamine at 50 mg/kg/d (0.39 +/- 0.06 mg/kg). In two of three patients studied, a significant (P < .025) increase in mean daily urinary iron excretion was achieved when the dose of L1 was increased to 100 mg/kg/d. Total iron balance studies, which quantitated both urinary and stool iron excretion on L1 and deferoxamine, determined that mean total daily iron excretion induced by deferoxamine (0.88 +/- 0.05 mg/kg) was significantly greater (P < .05) than that induced by L1 (0.53 +/- 0.17 mg/kg), attributable to the significantly greater stool iron excretion during deferoxamine treatment (0.50 +/- 0.16 mg/kg/d) compared with that measured during L1 treatment (0.12 +/- 0.08 mg/kg/d, P < .01). Stool iron excretion accounted for a significantly greater percentage of total iron excretion during deferoxamine treatment (59% +/- 20%) than during L1 treatment (23% +/- 14%, P < .01). These iron balance studies are the first to compare total iron excretion induced by L1 with that achieved by deferoxamine. They demonstrate that the mean total daily iron excretion during L1 treatment (0.53 +/- 0.17 mg/kg) is sufficient to maintain net negative iron balance in most regularly transfused patients with sickle cell disease. Because long-term compliance with L1 has been shown previously to be superior to that with deferoxamine in patients with homozygous beta-thalassemia, the use of L1 should increase the long-term effectiveness of iron chelation in patients with sickle cell disease.  相似文献   
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Chromosome analysis was performed in a 34‐year‐old man who was phenotypically normal except for oligoasthenozoospermia. In this patient, analysis of GTG‐banded chromosomes showed in one chromosome 8 additional chromosomal material of unknown origin. To characterize the aberrant chromosome more precisely, a paint specific for chromosome region 8pter → 8p23.1 was generated by microdissection and degenerated oligonucleotide primed‐polymerase chain reaction (DOP‐PCR) and used as fluorescence in situ hybridization (FISH) paint. After reverse painting, hybridization signals were only found on the short arm of the two chromosomes 8, with an enlarged signal on the derivative chromosome 8. The duplication was characterized further with band‐specific FISH probes. We concluded that (part of) chromosome region 8p23.1 → p23.3 was duplicated. Chromosome analysis of the parents showed that the dup(8) was of maternal origin and that the fertile brother of the index patient also was a carrier of the chromosome aberration. There was no history of miscarriages. We suggest that duplication of region 8p23.1 → p23.3 can be regarded as euchromatic variant or duplication with no phenotypic effect. Am. J. Med Genet. 91:18–21, 2000. © 2000 Wiley‐Liss, Inc.  相似文献   
386.
Research is lacking on factors influencing nurses' decision-making directed at the diagnosis of pain in children and its related interventions This paper reports on two studies, namely a qualitative study and its replication, in which we explored factors influencing nurses' pain assessments and interventions in children Those factors found to influence nurses' decisions were medical diagnosis, child's expressions, age, and parents, and the nurses' knowledge, experience, attitude and workload Some of these factors seem to have more influence than others For example, the presence of a medical diagnosis seems to legitimate being in pain Furthermore, it is suggested that mainly vocal expressions, especially crying, influence nurses' decisions to administer analgesics Finally, nurses' negative views on non-narcotic analgesics were striking In this paper, the results of both studies and their relationship to information reported in the literature are further elaborated and discussed, and hypotheses on strength and direction of influence of factors on pain assessment and intervention are generated  相似文献   
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Troponin-T (cTnT) as a marker of myocardial damage is well established in adults, but not yet in children. cTnT was measured in 85 children (aged 1 day-204 months, mean 46 months). Twenty-five children were non-surgical patients, with possible myocardial damage suspected on clinical grounds. The other 60 patients had cardiac surgery leading to a defined myocardial damage. In these children, troponin-T (cTnT), creatine kinase activity (CK), creatine kinase-MB activity (CK-MB), and creatine kinase-MB-Mass (CK-MB-Mass) were measured preoperatively and 3–4 times during the first 55 postoperative h. Except in four children with probable preoperative myocardial damage, all troponin-T values were in the normal range (< 0.1 μig/1). All children with intracardiac surgery showed a postoperative increase in troponin-T. Children with extracardiac surgery of the great vessels showed no postoperative increase of troponin-T. For the assessment of myocardial damage, troponin-T was more specific and more sensitive than the other markers tested, troponin-T might significantly improve the diagnostic assessment of myocardial damage in children.  相似文献   
389.
Anti-a2 sera raised in a3 rabbits are shown to detect determinants on a2 molecules which are different from those detected by anti-a2 sera raised in a1 animals. The former determinants are occasionally observed at a low level in rabbits of the a1 allotype and at a high level in sera of Leporidae of different genera. The two types of anti-a2 sera are shown to compete for the same sterical region of the a2 molecules. All homogeneous a2 molecules which have been tested show both types of determinants.  相似文献   
390.
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