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1.
The aim of this study was to determine whether patients with sickle cell disease (SCD) in steady state had pulmonary abnormalities seen on high-resolution computed tomography (HRCT) and whether any abnormalities correlated with contemporaneously diagnosed lung function abnormalities. A subsidiary question was whether the results of a noninvasive measure of haemolysis (end-tidal carbon monoxide (ETCO) levels) correlated with pulmonary function abnormalities. Thirty three patients with SCD, median (range) age 36 yrs (17-67 yrs) were examined. The degree of lobar volume loss and ground-glass opacification and prominence of central vessels on HRCT were quantitatively assessed. Pulmonary function was assessed by measurements of lung volumes, spirometry, gas transfer and oxygen saturation. ETCO levels were measured using an end-tidal CO monitor. Forced expiratory volume in one second (FEV1), forced vital capacity and total lung capacity significantly correlated with HRCT findings, particularly lobar volume loss. ETCO levels significantly negatively correlated with FEV1, vital capacity measured using a plethysmograph, specific airway conductance and arterial oxygen saturation measured by pulse oxymetry. In conclusion, the present results suggest that high-resolution computed tomography noninvasive assessment of haemolysis might be useful to identify sickle cell disease patients with respiratory function impairment.  相似文献   
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Two (ATT) trinucleotide repeat polymorphisms have been identified in the tails of Alu repeat elements in intron 5 of the antithrombin gene. The frequency and distribution of allele sizes for the Alu 5 and Alu 8 tail polymorphisms have been defined in a sample Caucasian population. The Alu 5 polymorphism has two alleles while that of Alu 8 has 10 alleles with a heterozygosity of 0.83. These polymorphisms have been used in combination with four previously described polymorphisms within the antithrombin gene to construct antithrombin gene haplotypes in the sample Caucasian population. Twenty-two different haplotypes were observed, with the Alu 8 polymorphism being particularly useful in subdividing the core haplotype based on the previously identified polymorphisms. The haplotype data were used to investigate the origin of repeat mutations within the antithrombin locus. We compared the haplotypes associated the mutant antithrombin genes in five families with the mutation 2759C→T (L99F) and five families with the mutation 5381C→T (R129Stop). The mutation 2759C→T (L99F), which occurs within a non-CpG dinucleotide, was carried on a gene associated with an identical haplotype in each of the five families. The mutation 5381C→T (R129Stop), a single base substitution within a CpG dinucleotide, was associated with at least two different haplotypes. The findings suggest a founder effect in the five families sharing the 2759C→T (L99F) and at least two independent origins for the CpG dinucleotide mutation 5381C→T (Rl29Stop). © 1994 Wiley-Liss, Inc.  相似文献   
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In order to describe presumed paediatric malaria on a cell-immunological basis, the soluble receptors of IL-2 (sIL-2R) and tumour necrosis factor (sTNF-R55 and sTNF-R75) were quantified in highly exposed young Tanzanian children. Sera were obtained from 66 acute and 72 reported febrile patients during health post consultations and follow-ups and from 68 community controls. Levels of sIL-2R, sTNF-R55 and sTNF-R75 were significantly elevated during fever attacks, especially in very young children. Soluble TNF-R75 levels were most stable and those of sTNF-R55 least. Levels of sTNF-R55 were related to the magnitude of fever and thus appeared to reflect attack severity. Levels of sTNF-R75 were highly significantly associated with parasite density, indicating that this response is malaria-specific. The present study indicates that sTNF-R75 levels could become a useful immunological tool in malaria intervention studies, as they reflect changes in malaria-specific immune responses. Future studies should validate this potential in different endemic settings.  相似文献   
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The clonal DNA content of the cell populations of primary tumors and corresponding lymph node metastases was analysed by DNA flow cytometry in 48 patients with squamous cell carcinoma of the oral cavity. Three primary tumors were diploid, two associated with diploid metastases, one showing an aneuploid cell line in the secondary lesion. Fourty-five cases were aneuploid in both the primary tumors and in the synchronous metastases, all characterized by nearly identical DNA indices of the corresponding primary and secondary lesions. With few exceptions, aneuploidy formation appears to take place prior to dissemination of metastatic cells.  相似文献   
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Sleeping accidents are a particular risk for infants and young children as they lack an understanding of potentially dangerous situations and are unable to self-extricate. These situations may result in deaths from asphyxia. While safety campaigns have focused on the faulty design of cots that are available for sale, modification of cots at home represents another potential problem area. A 17-month-old girl was found dead with her head wedged between the top side rail of her cot and a broomstick, which had been attached in an attempt to raise the height of the cot side. Death was due to neck compression from head entrapment. This case demonstrates that infant and toddler safe sleeping programmes should alert carers to the potential dangers of structurally altering cots or beds. Home modifications may create dangerous gaps that could result in entrapment with lethal neck compression; such alterations should be carefully assessed and documented by forensic death scene investigators.  相似文献   
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All artemisinin-based combination therapies (ACTs), recommended by the World Health Organization, are 3-day regimens. A considerable level of non-compliance on ACTs has been reported from some countries. The study aimed to assess the therapeutic efficacy of single dose treatment with new generation ACT containing artemisinin plus naphthoquine. An oral single dose of eight tablets (400 mg of naphthoquine + 1000 mg artemisinin) of the combination drug was administered to adult uncomplicated falciparum malaria patients. Observations of fever, parasite clearance and reappearance, and other clinical manifestations were made on Days 0, 1, 2, 3, 7, 14, 21 and 28. Fifty-three adult falciparum positive cases, with fever or history of fever within the previous 24 h, were included in the final evaluation of the study. Mean fever clearance time, parasite clearance time were 18.2 ± 8.6 h and 34.6 ± 14.3 h, respectively. Adequate clinical and parasitological response was achieved in 52 cases, the rate being 98.1% (95% CI, 91.1-99.9). One patient was classified as late parasitological failure because of the reappearance of falciparum parasite on Day 14. The drug was well tolerated and no adverse reactions were detected in the patients. Since it is a single dose therapy, health workers can administer the drug as directly observed treatment.  相似文献   
10.

Objectives

Recent studies using advanced statistical methods to control for confounders have demonstrated an association between helicopter transport (HT) versus ground ambulance transport (GT) in terms of improved survival for adult trauma patients. The aim of this study was to apply a methodologically vigorous approach to determine if HT is associated with a survival benefit for when trauma patients are transported to a verified trauma center in a rural setting.

Methods

The ascertainment of trauma patients age ≥ 15 years (n = 469 cases) by HT and (n = 580 cases) by GT between 1999 and 2012 was restricted to the scene of injury in a rural area of 10 to 35 miles from the trauma center. The propensity score (PS) was determined using data including demographics, prehospital physiology, intubation, total prehospital time, and injury severity. The PS matching was performed with different calipers to select a higher percentage of matches of HT compared to GT patients. The outcome of interest was survival to discharge from hospital. Identical logistic regression analysis was done taking into account for each matched design to select an appropriate effect estimate and confidence interval (CI) controlling for initial vital signs in the emergency department, the need for urgent surgery, intensive care unit admission, and mechanical ventilation.

Results

Unadjusted mortalities for HT compared to GT were 7.7 and 5.3%, respectively (p > 0.05). The adjusted rates were 4.0% for HT and 7.6% for GT (p < 0.05). In a PS well‐matched data set, HT was associated with a 2.69‐fold increase in odds of survival compared to GT patients (adjusted odds ratio = 2.69; 95% CI = 1.21–5.97).

Conclusions

In a rural setting, we demonstrated improved survival associated with HT compared to GT for scene transportation of adult trauma patients to a verified Level II trauma center using an advanced methodologic approach, which included adjustment for transport distance. The implication of survival benefit to rural population is discussed. We recommend larger studies with multiple trauma systems need to be repeated using similar study methodology to substantiate our findings.  相似文献   
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