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61.
CEDM is a recent development of digital mammography using the intra-venous injection of an iodinated contrast agent in conjunction with a mammography examination. Two techniques have been developed to perform CEDM examinations: the temporal subtraction technique with acquisition of high-energy images before and after contrast medium injection and the dual energy technique with acquisition of a pair of low and high-energy images only after contrast medium injection. The temporal subtraction technique offered the possibility to analyze the kinetic curve of enhancement of breast lesions, similarly to breast MRI. The dual energy technique do not provide information about the kinetic of tumor enhancement but allows the acquisition of multiples views of the same breast or bilateral examination and is less sensitive to patient motion than temporal CEDM. Initial clinical experience has shown the ability of CEDM to map the distribution of neovasculature induced by cancer using mammography. Moreover, previous studies have shown a superiority of MX+CEDM, either for the assessment of the probability of malignancy than for BIRADS assessment comparing to MX alone. The potential clinical applications are the clarification of mammographically equivocal lesions, the detection of occult lesions on standard mammography, particularly in dense breast, the determination of the extent of disease, the assessment of recurrent disease and the monitoring of the response to chemotherapy. CEDM should result in a simple way to enhance the detection and the characterization of breast lesions.  相似文献   
62.
The aim of this study was to evaluate the wear of denture teeth and their antagonists produced by two‐body and three‐body wear tests. Three types of denture teeth, namely feldspathic ceramic (FC), nano‐filled composite resin (NCR), and experimental acrylic resin teeth (AR), were tested. For each type two groups of eight upper premolars each were prepared. The first group was tested against cusps from the same material and the second group was tested against human enamel cusps. Each group was loaded with a total of 200,000 chewing cycles (two‐body wear 100,000 cycles and three‐body wear 100,000 cycles). Wear was analyzed by measuring the maximum depth and volume loss of the denture teeth using a laser scanner and by measuring the vertical loss of the antagonists using an optical macroscope. Statistically, there was no significant difference between the following combinations: FC–FC and NCR–NCR regarding the vertical and volume loss; and FC–enamel and NCR–enamel regarding the total vertical substance loss. The combinations AR–AR and AR–enamel showed higher wear values than the other combinations. For complete dentures, composite resin and ceramic teeth showed similar vertical and volume loss, whereas composite resin teeth seemed to be more suitable for partial dentures opposing natural teeth in terms of wear of teeth and antagonists.  相似文献   
63.
We have read with interest the article by Lu et al. entitled “Association of excessive mobile phone use during pregnancy with birth weight: an adjunct study in Kumamoto of Japan Environment and Children’s Study” published recently in the Environmental Health and Preventive Medicine. Although this paper addresses a very challenging issue, it has some shortcomings. Mortazavi et al. have previously studied the effects of ionizing and non-ionizing radiation on birth weight of newborns and found no statistical significant differences between the mean weight of newborns whose mothers had been exposed to electromagnetic fields (EMF) generated by mobile phones and those of non-exposed mothers. The study performed by Lu et al. cannot answer this very key question that whether ordinary use of mobile phone during pregnancy can lead to low birth weight. The origin of the controversy between the findings of these two studies and the shortcomings of the article by Lu et al. are discussed.  相似文献   
64.
Streptococcus mutans, a primary bacterium associated with dental caries, has four known clinical serotypes (c, e, fand k). Certain serotypes, the presence of multiple serotypes and strains with collagen‐binding proteins (CBP, Cnm and Cbm) have been linked with systemic disease. Evaluation of S mutans serotype distribution and caries association is needed in the United States. The purpose of this study was to evaluate the prevalence of S mutans serotypes from two cohorts of African‐American children in rural Alabama using three sample types (saliva, plaque and individual S mutans isolates) by PCR detection for association with caries. Detection of CBP was also performed by PCR. In total, 129 children were evaluated and overall prevalence of serotypes were: serotype c(98%), e(26%), f(7%) and k(52%). Serotype c was statistically associated with higher caries scores in older children (P < 0.001) and serotype k was statistically more likely in females (P = 0.004). Fourteen per cent of children had CBP. Thirteen S mutans isolates from five children tested positive for both CBP. This study is the first to report on the prevalence of S mutans serotypes in a US population using the PCR‐based approach. The frequency of serotype k in this study is the highest reported in any population, illustrating the need for further study to determine the prevalence of this clinically relevant serotype in the US. This is the first study to report S mutans isolates with both Cnm and Cbm in the same strain, and further analysis is needed to determine the clinical significance of these strains.  相似文献   
65.
Clinical Oral Investigations - Positive and negative influences on oral health are attributed to coffee consumption. The aim of the current study is to evaluate the association between coffee...  相似文献   
66.
67.
Lasers in Medical Science - In this experimental study, we aimed to evaluate the antibacterial and anti-biofilm effects of photodynamic therapy with a photosensitizer in conjunction with Gold...  相似文献   
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69.
Background: Ataxia telangiectasia (AT) is a primary immunodeficiency associated with recurrent infections. We aimed to investigate clinical and immunological classification in AT patients who suffer from a different spectrum of humoral immune defects.

Methods: AT patients were categorized according to the ability of class switching and patients with hyper IgM (HIgM) profile were defined as class switching defect (CSD).

Results: Serum immunoglobulin profile in 66 AT patients showed normal immunoglobulin level (22.8%), IgA deficiency (37.9%) and hypogammaglobulinemia (18.1%) in the majority of patients, while 21.2% had HIgM profile revealing CSD. CSD does not affect the frequency of infections, however, the frequency of lymphoproliferation (< 0.001), and autoimmunity (= 0.004) were significantly higher in this group. Neurologic symptoms in CSD patients are mild or appear after recurrent infections, therefore these patients were usually misdiagnosed as HIgM syndrome.

Conclusions: Although most of AT patients have reduced IgA levels or normal immunoglobulin levels, but a fraction of these patients may show CSD ensuing HIgM-profile. CSD poses affected individuals at higher risk of non-infectious complications.  相似文献   

70.
INTRODUCTION: Recent investigations have revealed that control of hyperglycaemia with insulin improves outcomes. The cornerstone of hyperglycaemia in critically ill patients is insulin resistance and it remains refractory to intensive insulin protocols. We designed this study to evaluate the efficacy and safety of a new intensive insulin therapy (IIT) protocol combined with metformin. METHODS: Twenty-one patients with systemic inflammatory response syndrome and a blood glucose level of >120 mg/dl admitted to an intensive care unit (ICU) were randomised to receive either intravenous infusion of IIT alone (n=11) or combined with metformin (IIT+MET; n=10) to maintain a blood glucose level (BGL) of 80-120 mg/dl. Blood samples were obtained at baseline and at 48 hours, 96 hours and 7 days after initiation of the study. Samples were analysed for interleukin-6 (IL-6), tumour necrosis factor alpha (TNF-alpha) and nitric oxide (NO) as inflammatory mediators; plasminogen activation inhibitor-1 (PAI-1) as a coagulation mediator; and thiobarbituric reactive substances (TBARS), total antioxidant power (TAP) and total thiol molecules (TTM) as oxidative stress parameters. RESULTS: The addition of metformin to the IIT protocol decreased insulin requirement and concentration of insulin and C-peptide. With both treatments at most time points, the mean plasma levels of IL-6, TNF-alpha, NO, PAI-1 and TBARS were found to be significantly lower compared with baseline. Antioxidant activity was increased in both arms with increasing TAP and TTM (P<0.05). There was no significant difference between the two groups regarding reported beneficial effects on these parameters. Therapeutic Intervention Scoring System-28 (TISS-28) score, an index of nursing workload and number of therapeutic interventions, decreased in the IIT+MET group (P<0.01). We did not observe any occurrence of hyperlactataemia or acidosis in the IIT+MET group. CONCLUSION: Metformin plus insulin appears to lower the incidence of insulin resistance, lower insulin requirement while maintaining blood glucose level control, and consequently lower the incidence of adverse effects related to high-dose insulin therapy, particularly hypoglycaemia, and also declined nursing workload. Both treatment protocols showed improvements in inflammatory cytokine levels. Further studies with larger sample sizes are warranted to determine the undiscovered facts of insulin-sensitising agents in critically ill patients.  相似文献   
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