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1.
Recurrent chromosomal rearrangements involving the 11q23 region have been described in various hematologic malignancies. Among these rearrangements, translocations are the most common mechanism involving the mixed lineage leukemia gene (MLL). Few cases of insertion have been reported and, to our knowledge, none of them involved MLL and chromosome 1. We report a complex karyotype in a childhood acute myelomonocytic leukemia (AML M4) involving the 11q23 region with an insertion between chromosomes 1 and 11 in addition to a translocation between chromosomes 11 and 22. This translocation was clarified by fluorescence in situ hybridization (FISH) analysis: 46,XY,ins(1;11)(q22q23;q13q23),t(11;22)(q13;q11q12). This finding also underlines the complementary contribution of conventional cytogenetic and FISH analysis to detect karyotypic complex abnormalities.  相似文献   
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Placental inflammation and perinatal transmission of HIV-1   总被引:2,自引:0,他引:2  
The effect of placental membrane inflammation on mother-to-child transmission (MTCT) of HIV-1 is reported. Placentas from HIV-1-infected women were examined as part of a perinatal HIV-1 project in Mombasa, Kenya. Polymerase chain reaction analysis was used to test for HIV-1 in the infants at birth and at 6 weeks. The maternal HIV-1 seroprevalence was 13.3% (298 of 2,235). The overall rate of MTCT of HIV-1 was 25.4%; polymerase chain reaction analysis revealed that of the 201 infants 6.0% (12) were already HIV-1-positive at birth (intrauterine transmission) and 19.4% (39) were infected during the peripartum period or in early neonatal life (perinatal transmission). The prevalence of acute chorioamnionitis was 8.8%, that of deciduitis was 10.8%, and that of villitis was 1.6%. Acute chorioamnionitis was independently associated with peripartum HIV-1 transmission but not with in utero MTCT (17.9% vs. 6.7%, respectively; adjusted odds ratio, 3.9; 95% confidence interval, 1.2-12.5; p =.025). Other correlates of perinatal MTCT were presence of HIV in the genital tract and in the baby's oral cavity and a high maternal viral load in peripheral blood. The adjusted population attributable fraction of 12.8% (95% confidence interval, 1.5%-22.8%) indicated that approximately 3% of MTCT could be prevented if acute chorioamnionitis was eliminated. We suggest that further research on the role of antimicrobial treatment in the prevention of chorioamnionitis and the reduction of peripartum MTCT needs to be performed.  相似文献   
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Protein supplements are increasingly used by older people to maintain nutrition and prevent or treat loss of muscle function. Daily protein requirements in older people are in the range of 1.2 gm/kg/day or higher. Many older adults do not consume this much protein and are likely to benefit from higher consumption. Protein supplements are probably best taken twice daily, if possible soon after exercise, in doses that achieve protein intakes of 30 gm or more per episode. It is probably not important to give these supplements between meals, as we have shown no suppressive effects of 30 gm whey drinks, and little if any suppression of 70 gm given to older subjects at varying time intervals from meals. Many gastrointestinal mechanisms controlling food intake change with age, but their contributions to changes in responses to protein are not yet well understood. There may be benefits in giving the supplement with rather than between meals, to achieve protein intakes above the effective anabolic threshold with lower supplement doses, and have favourable effects on food-induced blood glucose increases in older people with, or at risk of developing, type 2 diabetes mellitus; combined protein and glucose drinks lower blood glucose compared with glucose alone in older people.  相似文献   
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Background and Aim: Little is known about the causes of overt obscure gastrointestinal bleeding (OGIB) in patients using anti‐thrombotic therapy. We aimed to describe video capsule endoscopy (VCE) findings and to identify factors associated with positive findings in these patients. Methods: We carried out a retrospective study of 56 patients who underwent VCE for evaluation of previous overt OGIB during anti‐thrombotic therapy. VCE studies were re‐evaluated by a gastroenterologist blinded to clinical details. Clinical data included in the multivariate analysis were sex, age, indication for and type of anti‐thrombotic therapy, hemodynamic instability on admission, type of blood loss, hemoglobin on admission, use of a proton pump inhibitor, NSAID use, time between bleeding episodes and VCE, and whether or not anti‐thrombotic therapy was resumed before the VCE study. Results: A probable cause for gastrointestinal bleeding was identified in 28 (50%) of the 56 studies. Angiodysplasia was found in 19 patients. Twenty‐two studies showed a possible cause in the small bowel. Multivariate logistic regression analysis showed that reinstitution of anti‐thrombotic therapy before VCE was carried out was the only independent predictor of positive VCE findings (OR: 8.61, 95% CI: 1.20–60.42, P = 0.032). Conclusions: Small intestinal angiodysplasia was the most common cause for overt OGIB. Reinstitution of withdrawn anti‐thrombotic drugs before the VCE examination was carried out was associated with positive VCE findings in multivariate analysis.  相似文献   
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Purpose

Chlorhexidine oral care is widely used in critically and non-critically ill hospitalized patients to maintain oral health. We investigated the effect of chlorhexidine oral care on mortality in a general hospitalized population.

Methods

In this single-center, retrospective, hospital-wide, observational cohort study we included adult hospitalized patients (2012–2014). Mortality associated with chlorhexidine oral care was assessed by logistic regression analysis. A threshold cumulative dose of 300 mg served as a dichotomic proxy for chlorhexidine exposure. We adjusted for demographics, diagnostic category, and risk of mortality expressed in four categories (minor, moderate, major, and extreme).

Results

The study cohort included 82,274 patients of which 11,133 (14%) received chlorhexidine oral care. Low-level exposure to chlorhexidine oral care (≤?300 mg) was associated with increased risk of death [odds ratio (OR) 2.61; 95% confidence interval (CI) 2.32–2.92]. This association was stronger among patients with a lower risk of death: OR 5.50 (95% CI 4.51–6.71) with minor/moderate risk, OR 2.33 (95% CI 1.96–2.78) with a major risk, and a not significant OR 1.13 (95% CI 0.90–1.41) with an extreme risk of mortality. Similar observations were made for high-level exposure (>?300 mg). No harmful effect was observed in ventilated and non-ventilated ICU patients. Increased risk of death was observed in patients who did not receive mechanical ventilation and were not admitted to ICUs. The adjusted number of patients needed to be exposed to result in one additional fatality case was 47.1 (95% CI 45.2–49.1).

Conclusions

These data argue against the indiscriminate widespread use of chlorhexidine oral care in hospitalized patients, in the absence of proven benefit in specific populations.
  相似文献   
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