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101.

Background  

Improving the quality of health care requires a range of evidence-based activities. Audit and feedback is commonly used as a quality improvement tool in the UK National Health Service [NHS]. We set out to assess whether current guidance and systematic review evidence can sufficiently inform practical decisions about how to use audit and feedback to improve quality of care.  相似文献   
102.
103.

Background  

To gain insight into factors that might affect results of future case-control studies, we performed an analysis of children with sepsis and purpura admitted to the paediatric intensive care unit (PICU) of Erasmus MC-Sophia Children's Hospital (Rotterdam, The Netherlands).  相似文献   
104.

Background:

Fluorosis is one of the common but major emerging areas of research in the tropics. It is considered endemic in 17 states of India. However, the Cuddalore district of Tamil Nadu is categorised as a fluorosis non-endemic area. But clinical cases of dental fluorosis were reported in the field practice area of Department of Community Medicine, Rajah Muthiah Medical College, Annamalai University, Chidambaram. Since dental fluorosis has been described as a biomarker of exposure to fluoride, we assessed the prevalence and severity of dental fluorosis among primary school children in the service area.

Materials and Methods:

Children studying in six primary schools of six villages in the field practice area of Rural Health Centre of Faculty of Medicine, Annamalai University, Chidambaram, were surveyed. Every child was clinically examined at the school by calibrated examiners with Dean''s fluorosis index recommended by WHO (1997). Chi-square test, Chi-square trend test and Spearman''s rank correlation coefficient test were used for statistical analysis.

Results:

Five hundred and twenty-five 5- to 12-year-old school children (255 boys and 270 girls) were surveyed. The overall dental fluorosis prevalence was found to be 31.4% in our study sample. Dental fluorosis increased with age P < 0.001, whereas gender difference was not statistically significant. Aesthetically objectionable dental fluorosis was found in 2.1% of the sample. Villages Senjicherry, Keezhaperambai and Kanagarapattu revealed a community fluorosis index (CFI) score of 0.43, 0.54 and 0.54 with 5.6%, 4.8% and 1.4% of objectionable dental fluorosis, respectively. Correlation between water fluoride content and CFI values in four villages was noted to be positively significant.

Conclusion:

Three out of six villages studied were in ‘borderline’ public health significance (CFI score 0.4-0.6). A well-designed epidemiological investigation can be undertaken to evaluate the risk factors associated with the condition in the study region.  相似文献   
105.

BACKGROUND.

Endometrial cytology sampling devices for direct uterine sampling have been shown in previous studies to be a reliable and relatively painless method for detecting endometrial lesions. The purpose of the current study was to determine the performance characteristics of endometrial cytology for the detection of malignancy and atypical hyperplasia using liquid‐based cytology specimens collected with the Tao brush sampler.

METHODS.

Brushings of the endometrial cavity were obtained from 139 hysterectomy specimens before routine histopathologic evaluation. Cytology specimens were fixed in PreservCyt and processed using ThinPrep technology. Cytology diagnoses were classified as nondiagnostic, negative, atypical, or positive for malignancy. Histopathologic findings were used as the gold standard for determining the performance characteristics of cytology.

RESULTS.

Histopathologic results from the 139 patients included 81 (58%) endometrial cancers, 7 (5%) complex hyperplasias with atypia, 2 (1%) complex hyperplasias without atypia, and 49 (35%) patients with benign histology. The number of specimens diagnosed cytologically as positive, atypical, negative, or nondiagnostic was 60 (43%), 40 (29%), 37 (27%), and 2 (1%) specimens, respectively. The overall sensitivity and specificity of cytology for detecting endometrial cancer and atypical hyperplasia were 95% and 66% when atypical cytology specimens were considered positive.

CONCLUSIONS.

The results of the current study indicate that direct endometrial sampling by liquid‐based endometrial cytology collected with the Tao brush sampler produces specimens that contain cellular material that may be identified as endometrial cancer or atypical hyperplasia. Both atypical and positive cytology diagnoses are indicators for triage to more specific methods of diagnosis. Cancer (Cancer Cytopathol) 2008. © 2008 American Cancer Society  相似文献   
106.

Background and purpose:

This study investigates the role of α2-adrenoceptor subtypes, α2A, α2B and α2C, on catecholamine synthesis and catabolism in the central nervous system of mice.

Experimental approach:

Activities of the main catecholamine synthetic and catabolic enzymes were determined in whole brains obtained from α2A-, α2B- and α2C-adrenoceptor knockout (KO) and C56Bl\7 wild-type (WT) mice.

Key results:

Although no significant differences were found in tyrosine hydroxylase activity and expression, brain tissue levels of 3,4-dihydroxyphenylalanine were threefold higher in α2A- and α2C-adrenoceptor KO mice. Brain tissue levels of dopamine and noradrenaline were significantly higher in α2A and α2CKOs compared with WT [WT: 2.8 ± 0.5, 1.1 ± 0.1; α2AKO: 6.9 ± 0.7, 1.9 ± 0.1; α2BKO: 2.3 ± 0.2, 1.0 ± 0.1; α2CKO: 4.6 ± 0.8, 1.5 ± 0.2 nmol·(g tissue)−1, for dopamine and noradrenaline respectively]. Aromatic L-amino acid decarboxylase activity was significantly higher in α2A and α2CKO [WT: 40 ± 1; α2A: 77 ± 2; α2B: 40 ± 1; α2C: 50 ± 1, maximum velocity (Vmax) in nmol·(mg protein)−1·h−1], but no significant differences were found in dopamine β-hydroxylase. Of the catabolic enzymes, catechol-O-methyltransferase enzyme activity was significantly higher in all three α2KO mice [WT: 2.0 ± 0.0; α2A: 2.4 ± 0.1; α2B: 2.2 ± 0.0; α2C: 2.2 ± 0.0 nmol·(mg protein)−1·h−1], but no significant differences were found in monoamine oxidase activity between all α2KOs and WT mice.

Conclusions and implications:

In mouse brain, deletion of α2A- or α2C-adrenoceptors increased cerebral aromatic L-amino acid decarboxylase activity and catecholamine tissue levels. Deletion of any α2-adrenoceptor subtypes resulted in increased activity of catechol-O-methyltransferase. Higher 3,4-dihydroxyphenylalanine tissue levels in α2A and α2CKO mice could be explained by increased 3,4-dihydroxyphenylalanine transport.  相似文献   
107.

Background and purpose:

Tecarfarin (ATI-5923) is a novel vitamin K epoxide reductase inhibitor that is metabolized by esterase (mainly human carboxylesterase 2) to a single major metabolite, ATI-5900, in rats, dogs and humans. Tecarfarin is not significantly metabolized by CYP450 enzymes. The objective of this study was to test and compare the efficacy of tecarfarin with that of warfarin, when administered either intravenously or once a day orally, to produce stable anticoagulation in beagle dogs.

Experimental approach:

Effects on coagulation were assessed by measuring the activity levels of Factor VII and Factor X and thromboplastin-induced coagulation times, reported as prothrombin time (PT).

Key results:

Continuous intravenous infusions and oral administration of tecarfarin and warfarin caused a dose-dependent decrease in activity of Factor VII and Factor X, and associated increase in PT. Intravenous fresh frozen canine plasma or subcutaneous vitamin K1 treatment reversed the anticoagulant effects of orally administered tecarfarin. Consistent with the inhibitory effects of amiodarone on CYP2C9, co-administration of amiodarone significantly increased the anticoagulation effect of warfarin and plasma warfarin concentrations. In contrast, amiodarone had no effect on the anticoagulation induced by tecarfarin or tecarfarin plasma concentrations in this model.

Conclusions and implications:

Overall, the data presented herein indicate that tecarfarin, via a vitamin K-dependent mechanism, causes changes in key parameters of haemostasis in beagle dogs that are consistent with effective anticoagulation. Compared to warfarin it has a decreased potential to interact metabolically with drugs that inhibit CYP450 enzymes and, therefore, may offer an improved safety profile for patients.  相似文献   
108.
To address concerns over the prevalence of silent (antibody-negative) infections among blood donors and high-risk populations, a combination of proviral amplification by polymerase chain reaction (PCR) and viral isolation by co-culture techniques was employed to resolve the human immunodeficiency virus type 1 (HIV-1) infection status of well-characterized groups of suspect blood donors and others identified in the blood bank setting. No silent infections were found in 65 follow-up samples from 26 persistently HIV-1-seroindeterminate blood donors, 16 persistently seronegative heterosexual partners of infected transfusion recipients, and 6 high-risk seronegative homosexual men identified through donor look-back investigations. In contrast, 21 seropositive controls tested positive. These results suggest a low prevalence of persistently silent infections in at-risk populations, even in high HIV prevalence regions. The PCR assay, with a co-detected internal positive control, and appropriate confirmatory algorithms, was found to be a useful direct assay to rule out infection, especially in concert with confirmatory virus isolation.  相似文献   
109.
110.
Objectives: To evaluate the clinical utility of the City University of New York sentence test in a cohort of post-lingually deafened cochlear implants recipients over time.

Methods: 117 post-lingually deafened, Australian English-speaking CI recipients aged between 23 and 98 years (M?=?66 years; SD?=?15.09) were recruited. CUNY sentence test scores in quiet were collated and analysed at two cut-offs, 95% and 100%, as ceiling scores.

Results: CUNY sentence scores ranged from 4% to 100% (M?=?86.75; SD?=?20.65), with 38.8% of participants scoring 95% and 16.5% of participants reaching the 100% scores. The percentage of participants reaching the 95% and 100% ceiling scores increased over time (6 and 12 months post-implantation).

The distribution of all post-operative CUNY test scores skewed to the right with 82% of test scores reaching above 90%.

Discussion: This study demonstrates that the CUNY test cannot be used as a valid tool to measure the speech perception skills of post-lingually deafened CI recipients over time. This may be overcome by using adaptive test protocols or linguistically, cognitively or contextually demanding test materials.

Conclusion: The high percentage of CI recipients achieving ceiling scores for the CUNY sentence test in quiet at 3 months post-implantation, questions the validity of using CUNY in CI assessment test battery and limits its application for use in longitudinal studies evaluating CI outcomes. Further studies are required to examine different methods to overcome this problem.  相似文献   
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