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31.
Psychiatric Quarterly - Our study systematically reviews articles about the prevalence of Post-traumatic Stress Disorder (PTSD) among children and adolescents, aiming to evaluate its prevalence...  相似文献   
32.
Background The immunological abnormalities that lead to the development of psoriasis suggest that these patients may be at increased risk for other inflammatory state which may enhance atherosclerosis. Objective To assess the presence of subclinical atherosclerosis in psoriatic patients who haven't associated traditional cardiovascular risk factors, and to correlate these findings with colour Doppler echocardiographic parameters. Methods The study included 80 patients with chronic psoriasis together with 50 age and sex matched healthy volunteers served as control group. Patients who had classic cardiovascular risk factors or had cardiovascular or cerebrovascular events were excluded. Carotid artery intima‐media thickness (IMT) and carotid plaques were measured in the carotid arteries by using high‐resolution B‐mode ultrasound. Also, echocardiographic study was performed using ultrasound imaging system in all cases and controls. Results Patients with psoriasis had increased carotid artery IMT compared with controls (means 0.9 ± 0.2 mm vs. 0.7 ± 0.1 mm; P < 0.001). Carotid IMT positively correlated with patients age, duration of the disease and severity of psoriasis. There was no significant difference in echocardiographic parameters in psoriatic patients compared with controls, also no significant correlation between carotid IMT and echocardiographic parameters were observed in psoriatic patients. Conclusion The increased carotid artery IMT in patients with chronic psoriasis suggesting that chronic psoriasis is associated with subclinical atherosclerosis with increased risk of cardiovascular disease. So, dermatologists should advice their patients to avoid traditional cardiovascular risk factors and to routinely checkup to reduce cardiovascular morbidity and mortality.  相似文献   
33.

Background

Fractures of acrylic resin dentures are a common occurrence in clinical dentistry. The denture may be fractured accidentally when dropped or while in service in the mouth due to flexural fatigue.

Objectives

The aim of this study was to compare the elastic modulus and the flexural strength between two heat-cured acrylic resins used in denture bases: a high-impact resin (Lucitone 199) and a traditional resin (Rodex).

Materials and methods

Rectangular strips of Lucitone 199 and Rodex (10 samples each) were fabricated and stored in artificial saliva at 37 °C for 2 weeks. The specimens were subjected to a three-point flexural test. The data were statistically analysed with Student’s t-test (p ⩽ .05).

Results

The high-impact acrylic resin had a lower elastic modulus (p = .000) and higher flexural strength (p = .001) compared to the traditional acrylic resin.

Conclusion

Within the limitations of this study, it can be concluded that the high-impact acrylic resin is a suitable denture base material for patients with clinical fracture of the acrylic denture.  相似文献   
34.
Among extracorporeal liver support devices, liver dialysis is cleared by the U.S. Food and Drug Administration to be used for the management of fulminant hepatic failure (FHF). The outcomes of patients following liver dialysis need to be clearly evaluated. Among the 25 patients with FHF admitted to the Liver ICU between May 2000 and November 2002, 12 underwent liver dialysis, including 6 men and 6 women, of mean age 32 years. The causes of FHF were identified as acetaminophen (n = 10), herbal medications (n = 1) and autoimmune disease (n = 1). At presentation, the mean total bilirubin was 9.35 mg/dL (range, 0 to 1.3), mean ALT 3015 U/L (range, 0 to 48), mean AST 3457 (range, 0 to 42), mean ammonia 98 micromol/L (range, 10 to 60) and mean INR 1.88. A control group including 13 patients (2 men and 11 women), of mean age 27.8 years mean total bilirubin 5.66, mean ALT 3494, mean AST 3528, mean ammonia 113 and mean INR 3, were not treated with liver dialysis, due to the lack of machine availability or physician's choice. The causes of FHF were acute hepatitis B (n = 1), acetaminophen (n = 10) or unknown (n = 2). There was no statistically significant difference in the baseline characteristics of the two groups (P >.05). Among the liver dialysis group, 1 patient died, 2 underwent OLTx, and 9 were discharged home. Among the control group; 4 patients died, 2 underwent OLTx, and 7 were discharged home. Preliminary results seem to support survival benefit among patients who underwent liver dialysis compared to non-liver dialysis; however, further randomized control trials are warranted to verify this observation.  相似文献   
35.
The objective of this work was to establish a new procedure for 228Ra determination of natural waters via preconcentration of radium on MnO2 and separation of its daughter, 228Ac, using Diphonix ion exchange resin. Following removal of potential interferences via passage through an initial Diphonix Resin column, the first daughter of 228Ra, 228Ac, is isolated by chromatographic separation via a second Diphonix column. A holding time of >30 h for 228Ac ingrowth in between the two column separations ensures secular equilibrium. Barium-133 is used as a yield tracer. Actinium-228 is eluted from the second Diphonix Resin with 5 ml 1 M 1-Hydroxyethane-1,1-diphosphonic acid (HEDPA) and quantified by addition of scintillation cocktail and LSC counting. Radium (and 133Ba) from the load and rinse solutions from the 2nd Diphonix column may be prepared for alpha spectrometry (for determination of 223Ra, 224Ra, and 226Ra) by BaSO4 microprecipitation and filtration. Decontamination tests indicate that U, Th, and Ra series nuclides do not interfere with these measurements, although high contents of 90Sr (90Y) require additional treatment for accurate measurement of 228Ra. Addition of stable Sr as a “hold back” carrier during the initial MnO2 preconcentration step was shown to remove most 90Sr interference.  相似文献   
36.
The predicted primary structure of the measles virus hemagglutinin   总被引:21,自引:0,他引:21  
The complete nucleotide sequence of cloned cDNAs corresponding to the full length of the mRNA encoding the measles virus hemagglutinin (H) protein has been determined. the mRNA contains a single large open reading frame which is capable of encoding a protein of 617 amino acids with a molecular mass of 69,250 Da. The deduced amino acid structure of the protein indicates that the only major hydrophobic region of sufficient length to anchor the molecule in membranes is located near the amino terminus. Comparison of the amino acid structure of the measles virus H protein with that of the hemagglutinin-neuraminidase (HN) molecules of Sendai virus and simian virus 5 (SV5) reveals little homology. However, 11 of the 13 cysteine residues found in the measles H protein can be aligned with cysteines in the Sendai virus HN protein in similar positions relative to one another. Five potential N-linked glycosylation sites are present in the measles H protein sequence. These are relatively closely grouped between amino acids residues 168 and 240 in the amino terminal half of the molecule. No obvious structural features are present in the measles H protein amino acid sequence which might explain the reported absence of neuraminidase activity associated with the molecule.  相似文献   
37.
38.
The study of Histocompatibility Locus Antigen (HLA) frequencies in 48 cases with congenital heart disease (CHD) in children in Cairo showed high incidence of A10. Cases with atrial septal defect have shown a significant association with A3 besides A10. There is also a significant association between B12-45 and right loop anomalies (Fallot's and pulmonary stenosis) together with A10. On the other hand, children with rheumatic heart disease have shown strong positive association with HLA group B8 and negative association with A28.  相似文献   
39.
A range of anorectal malformations with sacral bony abnormalities was found in members from three generations of two kindreds. The anorectal anomaly was low in all but one of the patients. Partial sacral agenesis was the main bony defect in one family, and meningomyelocele and spina bifida occulta were noted in the second. The inheritance pattern in these kinships is autosomal dominant. This may be a variant of caudal regression syndrome, which seems to be aetiologically heterogeneous.  相似文献   
40.
PURPOSETo evaluate the relationship among feeding arterial pressure, lesion size, and perfusion in cerebral cortex adjacent to cerebral arteriovenous malformations (AVMs).METHODSEleven patients with hemispheric AVMs underwent 99mTc hexamethyl-propyleneamine oxime single-photon emission CT before and after 1 g of acetazolamide was administered intravenously. AVM volume was estimated from MR dimensions and measured according to the method described by Pasqualin. Pressure measurements were obtained in arteries feeding the cortex adjacent to AVMs. Single-photon emission CT regions of interest were defined in cortex adjacent to the AVM and compared with contralateral regions using the Mountz method to estimate a baseline and dynamic (acetazolamide-challenged) perfusion defect volume.RESULTSEight of 11 patients had baseline perfusion defects, but these defects were unrelated to feeding artery pressures (y = -.06x + 9.92, r2 = .04) or the dynamic change in defect volume after acetazolamide administration (y = .01x + .02, r2 = .002). However, there was a correlation between AVM volume and the baseline defect volume (y = .75x - 1.9, r2 = .76). Five patients had increased defect volume after acetazolamide administration; 5 patients had either no change in or improvement of perfusion. Dynamic changes in defect volume were related to feeding artery pressures.CONCLUSIONPerilesional baseline perfusion defects appear to be related to lesion size and not to local arterial pressure. Cerebrovascular reserve generally was preserved, and perfusion defects appeared to be more pronounced with lower arterial pressures in feeding vessels. Although vasodilatory testing can unmask hemodynamic failure with severe local hypotension, baseline perfusion defects near the lesion and distant perfusion changes are more likely attributable to other causes such as mass-related or neurogenic changes.  相似文献   
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