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51.
We studied the aetiology of malnutrition in a cohort of 1511 children < 10 years old in Espiritu Santo, Vanuatu. Malnutrition was categorized using standard anthropometric criteria as: underweight [weight-for-age (WA) Z score < -2], wasting [weight-for-height (WH) Z < -2], or stunting [height-for-age (HA) Z < -2]. On multiple logistic regression analysis, the only factors significantly associated with wasting were age < 5 years [OR (95% CI) 1.8 (1.2-2.9), p = 0.01] and having suffered one or more episodes of clinical P. vivax malaria in the 6 months preceding nutritional assessment [OR 2.4 (1.3-4.4), p = 0.006]. The incidence of P. vivax infection was significantly higher during the 6 months preceding assessment in underweight vs. non-underweight children [incidence rate ratio (IRR) 2.6 (1.5-4.4), p < or = 0.0001). These groups had similar incidences of clinical P. falciparum infection during the same period [IRR 1.1 (0.57-2.1) p = 0.8] and of either species during the 6 months following assessment [IRR P. vivax 1.3 (0.9- 2.0) p = 0.2; IRR P. falciparum 1.3 (0.9-1.9) p = 0.2]. In these children, P. vivax malaria was a major predictor of acute malnutrition; P. falciparum was not. Wasting neither predisposed to nor protected against malaria of either species. Although P. vivax malaria is generally regarded as benign, it may produce considerable global mortality through malnutrition.   相似文献   
52.
The Concorde trial compared immediate (Imm) with deferred (Def) AZT monotherapy in asymptomatic HIV-positive participants. Haematological and immunological markers and weight were measured throughout, and correlated with clinical endpoints. Markers associated with disease progression (CD4 lymphocyte count and percentage, platelets, p24 antigen and beta 2 microglobulin favoured Imm: those associated with toxicity (haemoglobin, neutrophils and white cell count) favoured Def. CD8 and total lymphocyte count did not differ significantly between groups. In multivariate analysis, the combination of baseline CD4, p24 antigen and beta 2m was the best baseline predictor of disease. Including change in CD4 and beta 2m at 12 weeks, or changes over follow- up in these markers significantly improved the fit. Markers were also incorporated into the definition of 'clinical' endpoints. Hazard ratio estimates from end-points that included CD4 < 50 and CD4 < 25 were closest to those for AIDS or death alone, but added very few extra events. Use of other landmark CD4 counts (100 or greater) or relative decreases in counts (25% or more) increased the number of events, but overestimated the effect of immediate AZT. Although AZT had a beneficial effect on the surrogate markers of efficacy evaluated, these changes did not predict clinical outcome, nor could the markers be usefully incorporated into an endpoint definition.   相似文献   
53.
INTRODUCTION: Tissue factor (TF) has been implicated in coronary artery disease (CAD). High levels of circulating TF are found in patients with acute atherothrombotic events. Whether high serum TF levels predict risk of future CAD independent of known risk factors remains unknown. METHODS: We conducted a prospective case-control study nested in the European Prospective Investigation into Cancer and Nutrition (EPIC)-Norfolk population study. Cases (n=1037) were apparently healthy men and women, aged 45-79 years, who developed fatal or non-fatal CAD during follow-up. Controls (n=2005) were matched by age, sex, and enrolment time. Serum TF levels were measured using high-affinity antibodies. RESULTS: In men, median TF levels were not significant higher in cases than in controls (59.0 pg mL-1, range: 16.7-370.4 vs. 54.9 pg mL-1, range: 16.2-452.4). In women, median TF levels were not significant higher in controls than in cases (73.4 pg mL-1, range: 16.7-492.3 vs. 50.5 pg mL-1, range: 16.5-376.7). The incidence of smoking was about double in the lowest compared with the highest TF quartile. Correcting for sex, age, body mass index, smoking, diabetes, systolic blood pressure, low-density lipoprotein-cholesterol, high-density lipoprotein-cholesterol and C-reactive protein levels, the risk of future CAD was 1.05 (95% CI: 0.81-1.36) for people in the highest TF quartile, compared with those in the lowest (P-value for linearity=0.8). CONCLUSION: High levels of serum TF were not independently associated with an increased risk of future CAD in apparently healthy individuals.  相似文献   
54.
The biocompatibility of nine different white cell filters was examined by analysis of complement activation in plasma specimens obtained from blood components before and after filtration. Filters for both red cell (RBC) concentrates and platelet concentrates (PCs) were tested. It was found in all of the filters tested that the postfiltration levels of complement activation products were not higher than the prefiltration levels in RBC concentrates and PCs. One exception was the filtration of multiple PCs with Imugard IG-500, in which case a rise in C3 activation products was seen. Moreover, there was a significant rise in C3 activation products, but not the terminal complement complex, when plasma was filtered through Imugard E, which contrasted with results with the other filters. High initial and storage time-dependent levels, especially of C3 activation products, were observed in the PCs, probably due to their processing at room temperature. It can be concluded that the majority of the filters tested do not activate complement.  相似文献   
55.
BACKGROUND: Platelet concentrates prepared from whole blood are generally suspended in a standard volume of 50 to 60 mL of plasma and can be stored thus at 20 to 24 degrees C for up to 5 days. In vitro studies suggested that this plasma volume could be reduced to 30 to 35 mL without impairing platelet function. STUDY DESIGN AND METHODS: This study evaluated whether platelets stored for 5 days in a reduced volume (30-35 mL) of plasma maintained their in vivo viability, hemostatic function, and recovery in recipients. Paired autologous platelet survival studies were done in 20 adult volunteers to assess platelet viability. A rabbit ear bleeding-time model was used to compare the hemostatic effectiveness of human platelet concentrates stored for 5 days in the standard or reduced volume of plasma. Platelet recovery was compared in thrombocytopenic hospital patients. RESULTS: Paired platelet survival studies indicated no significant difference between the values in platelet concentrates stored for 5 days in the reduced volume of plasma and the values in those stored in the standard volume. In the animal model, there was no significant difference in the bleeding times achieved by either set of platelet concentrates. The platelet count increments in thrombocytopenic patients were measured. The platelet count increments in patients who received reduced-volume platelet concentrates were as good as the increments achieved in patients given standard-volume concentrates. CONCLUSION: The in vivo viability, recovery, and hemostatic function of platelets collected in polyvinylchloride plastic containers and stored in 30 to 35 mL of plasma for 5 days are maintained as well as those of platelets stored in 50 to 60 mL of plasma.  相似文献   
56.
BACKGROUND: Prolonged survival in pediatric patients with short bowel syndrome (SBS) is now possible because of parenteral nutrition and small bowel transplantation. We hypothesized that there may be important differences between adult patients who developed SBS during early childhood and those who develop this as adolescents. METHODS: Sixty-seven patients between the ages of 16 and 40 years were studied. Thirty patients developing SBS younger than 12 years comprised the pediatric group (PG), 37 developing SBS at age 13 to 25 constituted the adolescent group (AG). RESULTS: Midgut volvulus (n=11) was the most common cause in the PG followed by gastroschisis (n=5), intestinal atresia (n=5), and necrotizing enterocolitis (n=4). The most common cause of SBS in the AG was trauma (n=13), followed by tumors (n=7) and postoperative complications (n=5). A similar portion in each group had intestinal remnants less than 60 cm (69% vs. 58%), however, the PG was more likely to have a colon remnant (97% vs. 71%, P<0.05), and less likely to have an ostomy (7% vs. 47%, P<0.05). Patients in PG were followed significantly longer than AG (246+/-67 vs. 90+/-58 months, P<0.05). A similar portion of the patients require long-term parenteral nutrition (86% vs. 84%) or have undergone intestinal transplant (28% vs. 23%). Significantly more pediatric patients had negative height z scores when compared with the adolescents. CONCLUSIONS: Acknowledging the inherent biases created in defining the two groups, pediatric patients developing SBS early in life seem to be similar to those who develop SBS as adolescents with regards to long-term outcome, despite differences in origin and intestinal anatomy.  相似文献   
57.
Systemic sclerosis (SSc) is an autoimmune systemic disease characterized by small vessel involvement that leads to tissue ischemia and fibroblast stimulation resulting in accumulation of collagen (fibrosis) in the skin and internal organs. Lipomembranous panniculitis is a peculiar type of fat necrosis and has been reported with clinical conditions, commonly with peripheral vascular diseases. We describe a case of a 43‐year‐old woman with SSc manifestations, who presented with black scaly skin plaques, associated with thickening of the subcutaneous fat tissue, on the lateral surface of her thighs, her calves, gluteal area and lower abdomen. Biopsy revealed lipomembranous panniculitis. Lipomembranous changes have been seen in connective tissue disorders such as lupus profundus, morphea, systemic sclerosis and panniculitis associated with dermatomyositis, but rarely in thighs, calves, gluteal area and lower abdomen. Almeida MSTM, Lima SCB, Carvalho LL, Almeida JVM, Santos LG, Rolim JRA, Rocha TE. Panniculitis–An unusual cutaneous manifestation of systemic sclerosis.  相似文献   
58.
59.
Presence of an associated azygos lobe may cause problems during thoracotomy on the right side for esophageal atresia. Awareness of the anomaly allows its recognition and appropriate management.  相似文献   
60.
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