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31.
Williams TN; Maitland K; Phelps L; Bennett S; Peto TE; Viji J; Timothy R; Clegg JB; Weatherall DJ; Bowden DK 《QJM : monthly journal of the Association of Physicians》1997,90(12):751-757
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
32.
Walker AS; Peto TE; Babiker AG; Darbyshire JH 《QJM : monthly journal of the Association of Physicians》1998,91(6):423-438
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
33.
T. T. KELLER C. NAGEL H. TE VELTHUIS† V. E. A. GERDES N. J. WAREHAM‡ S. A. BINGHAM§ R. LUBEN¶ C. E. HACK P. H. REITSMA†† M. LEVI K. T. KHAW¶ S. M. BOEKHOLDT‡‡ 《Journal of thrombosis and haemostasis》2006,4(11):2391-2396
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
34.
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
35.
Platelet concentrates stored for 5 days in a reduced volume of plasma maintain hemostatic function and viability 总被引:2,自引:0,他引:2
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
36.
Schenkel LS Pavuluri MN Herbener ES Harral EM Sweeney JA 《Journal of the American Academy of Child and Adolescent Psychiatry》2007,46(8):1070-1079
OBJECTIVE: Past investigations indicate facial emotion-processing abnormalities in pediatric bipolar disorder (PBD) subjects. However, the extent to which these deficits represent state- and trait-related factors is unclear. We investigated facial affect processing in acutely ill and clinically stabilized children with PBD and matched healthy subjects. METHOD: Subjects (N = 86) consisted of unmedicated/acutely ill (n = 29) and medicated/clinically stabilized (n = 29) PBD youths and matched healthy subjects (n = 28) who completed tasks of facial affect identification and differentiation. RESULTS: Subjects with PBD, regardless of clinical and treatment status, showed marked impairments in the ability to correctly identify emotionally intense happy and sad facial expressions, with both groups tending to misjudge extreme facial expressions as being moderate to mild in intensity. However, when differentiating subtle variations of happy or sad expressions, only unmedicated/acutely ill PBD patients performed more poorly than healthy subjects. Younger age at onset was associated with more impaired emotion processing only in the PBD sample. PBD subjects with comorbid attention-deficit/hyperactivity disorder (ADHD) performed more poorly than subjects without ADHD when processing sad facial expressions, but not happy ones. CONCLUSIONS: This study found evidence of both state-of-illness and trait-related deficits in emotion processing in PBD. Treatments are needed to better reduce this impairment and to reduce its developmental impact on interpersonal functioning. 相似文献
37.
Herbener ES 《Schizophrenia bulletin》2008,34(5):875-887
Emotional memories play an important role in our day-to-day experience, informing many of our minute-to-minute decisions (eg, where to go for dinner, what are the likely consequences of not attending a meeting), as well as our long-term goal setting. Individuals with schizophrenia appear to be impaired in memory for emotional experiences, particularly over longer delay periods, which may contribute to deficits in goal-related behavior and symptoms of amotivation and anhedonia. This article reviews factors that are known to influence emotional memory in healthy subjects, applies these factors to results from emotional memory studies with individuals with schizophrenia, and then uses extant neurobiological models of emotional memory formation to develop hypotheses about biological processes that might particularly contribute to emotional memory impairment in schizophrenia. 相似文献
38.
39.
GABRIEL O. TE MD MARGARET J. HAMILTON MA FRANKLIN M. RIZER MD KIMBERLY A. SCHATZ MA PETER N. ARKIS MA HEATHER C. ROSE MA Made possible by a grant from the Warren Hearing Research Foundation. 《Otolaryngology--head and neck surgery》1996,115(6):508-512
A number of studies have demonstrated that cochlear implants provide an improved auditory signal and enhance the development of speech-perception and production skills for profoundly deaf children. However, exactly when these early speech skills begin to develop remains unclear. To explore this issue, we observed, for a 1-year period, four prelingually deaf children who underwent implantation consecutively within 1 month of each other, and we paid particular attention to the first few months of rehabilitation. We found immediate speech scores as early as the first day of implant tune-up. Speech production continued to improve rapidly throughout the first 4 months but exhibited a generally slower rate of progress in some of the speech-production skills at 1 year. We also found vowel-production skills to be the easiest to achieve, with word-pattern recognition and consonant voicing of intermediate difficulty. Consonant placing and manner of consonant production were the hardest skills to achieve. Results of speech-perception tests 1 year after implantation were markedly improved over preimplantation levels in three of the four children. These early speech changes stress the need for maximization of the capability of the cochlear implant by institution of immediate and intensive speech rehabilitation efforts for prelingually deaf children. (Otolaryngol Head Neck Surg 1996;115:508-12.) 相似文献
40.
PJ Smith ; TE Miller ; J Fraser ; JW Smith ; JR Svirbely ; S Rudmann ; PL Strohm ; M Kennedy 《Transfusion》1991,31(4):313-317
Four empirical studies were conducted for better understanding of the nature of problem-solving activities by medical technologists and medical technology students when performing antibody identification tasks. The results indicated the importance of strategies that ensure the collection of converging evidence, as these strategies protect against the fallibility of commonly used heuristics and against errors due to simple slips. The results also indicate that not only do students make significant numbers of errors, but so do practicing technologists. In one of the studies covering a 1-year period, for instance, a group of 16 technologists made a total of 41 errors in 1057 cases. On the basis of these findings, several alternatives are proposed to reduce errors. 相似文献