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Objective To determine the current eyecare behaviour of dentists and compare this against published standards concerning frequency of sight test intervals and eye protection.Design Postal questionnaire.Subjects and methods Four hundred dentists were selected at random for inclusion in the study from the UK 2004 Dentists Register. They were invited to complete a questionnaire that ascertained their gender and age, current eyesight status and method of correction, elapsed time interval since their last eyesight test and reason for attendance. In addition, the use and power of magnification was sought along with the adoption of protective eyewear. Responses were coded and placed in a relational database to facilitate interrogation and subsequent statistical analysis.Results The questionnaire return rate was 63% (247 and allowing for the seven questionnaires returned marked unknown at this address). Of these 158 were males and 81 female. The majority worked in general dental practice. Those with known eyesight deficiencies were statistically more likely (p <0.01) to attend for routine eye examination. Sixteen percent of respondents failed to attend for routine eye examination at least every two years. The mean age of those who had detected a change in their eyesight and sought examination was 43.59 (SD = 10.57) for males and 39.07 years (SD = 9.41) for females. This mirrored closely the mean age when the use of magnification was adopted (males = 42.39 (10.30), females = 40.33 (10.55)). The use of magnification was not universally adopted. Eye protection compliance was a low as 57% when using laboratory cutting equipment.Conclusions Although compliance with accepted recommendations for biannual eyesight testing was higher than that for the general population, not all dentists complied. The adoption of protective eyewear was patchy and exposed dentists to unnecessary risk.  相似文献   
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Variations of the nonrecombining Y‐chromosomal region were investigated in 159 unrelated Baltic‐speaking ethnic Latvians from four different geographic regions, using 28 biallelic markers and 12 short tandem repeats. Eleven different haplogroups (hgs) were detected in a regionally homogeneous Latvian population, among which N1c, R1a, and I1 cover more than 85% of its paternal lineages. When compared its closest geographic neighbors, the composition of the Latvian Y‐chromosomal gene pool was found to be very similar to those of Lithuanians and Estonians. Despite the comparable frequency distribution of hg N1c in Latvians and Lithuanians with the Finno‐Ugric‐speaking populations from the Eastern coast of the Baltic Sea, the observed differences in allelic variances of N1c haplotypes between these two groups are in concordance with the previously stated hypothesis of different dispersal ways of this lineage in the region. More than a third of Latvian paternal lineages belong specifically to a recently defined R1a‐M558 hg, indicating an influence from a common source within Eastern Slavic populations on the formation of the present‐day Latvian Y‐chromosome gene pool.  相似文献   
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The mycotoxin zearalenone (ZEN) is frequently contaminating animal feeds including feed used in aquaculture. In the present study, the effects of dietary exposure to ZEN on carp (Cyprinus carpio L.) were investigated. ZEN at three different concentrations (low dose: 332 µg kg−1, medium dose: 621 µg kg−1 and high dose: 797 µg kg−1 final feed, respectively) was administered to juvenile carp for four weeks. Additional groups received the mycotoxin for the same time period but were fed with the uncontaminated diet for two more weeks to examine the reversibility of the ZEN effects. No effects on growth were observed during the feeding trial, but effects on haematological parameters occurred. In addition, an influence on white blood cell counts was noted whereby granulocytes and monocytes were affected in fish treated with the medium and high dose ZEN diet. In muscle samples, marginal ZEN and α-zearalenol (α-ZEL) concentrations were detected. Furthermore, the genotoxic potential of ZEN was confirmed by analysing formation of micronuclei in erythrocytes. In contrast to previous reports on other fish species, estrogenic effects measured as vitellogenin concentrations in serum samples were not increased by dietary exposure to ZEN. This is probably due to the fact that ZEN is rapidly metabolized in carp.  相似文献   
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BackgroundEarly detection of mental retardation and other epilepsy-associated impairments is essential for successful medical and social care of children with epilepsy; the corresponding information for children in Croatia has not yet been known.Aims of the studyTo obtain the basic information of epilepsy-associated disability in preschool children, and fundamentals of their medical and social care.MethodsData about mental retardation and other associated impairments (motor, speech, seeing, hearing), antiepileptic drug therapy and diurnal residence were collected by means of questionnaires completed by physicians working in primary health care (PHPs). Only children (0–7 years) with active epilepsy confirmed previously by neuropaediatricians were included.ResultsA total of 37 PHPs provided the required data for 116 children. One or more impairments were found in 56% children; most frequent were motor impairments (47%), speech impairments (42%) and mental retardation (40%). The regular kindergarten attendance rate of children without impairment (33%) was not different from the children without epilepsy, but high proportion (76%) of children with impairment stayed with their families during weekdays. In this subgroup monotherapy was more rarely used (64% vs. 90% in children without impairment (p < 0.01)). Valproate was predominantly used (56%) in children with and without impairment; lamotrigine was more frequently used in the former subgroup (p < 0.01).ConclusionsExistence of associated impairments has significant impact on medical and social care in preschool children with epilepsy. These children need an early diagnosis and consecutive multidisciplinary care of their intellectual and body impairments, as well as problems in social development.  相似文献   
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INTRODUCTION: Brain natriuretic peptide (BNP) is produced by the ventricles of the heart and is a biomarker for heart failure. Several commercial assays are now available. We evaluated the performance characteristics of the ARCHITECT BNP assay. METHODS: We evaluated the limit of blank, limit of detection, linearity and imprecision. Method comparison studies were performed with 3 other automated BNP assays including the ADVIA Centaur, AxSYM, and UniCel DxI 800 methods. RESULTS: The mean LOB and LOD of the Architect assay were 3.5 and 5.8 ng/L, respectively. Imprecision studies yielded within run CVs of 1.1 to 5.1% and total CVs of 2.3 to 5.3% using human plasma based multi-constituent controls at concentrations of 92, 500, and 3500 ng/L. The maximum deviation from the target recovery for dilution linearity was 9.6%. Concordance with other BNP assays at a 100 ng/l cutoff was 91 to 98% and kappa statistics were 0.78 to 0.96. The mean difference between the Architect and Advia Centaur methods was positive. For the other methods, the mean difference with the Architect was negative. CONCLUSIONS: The Architect BNP assay shows good performance characteristics with total imprecision < or =5.3%. It agrees well with the Advia Centaur, AxSYM, and UniCel DxI BNP assays.  相似文献   
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Hypertension remains disproportionately high among Filipinos compared to other racial and ethnic minority populations, and little research on cardiovascular disease risk factors has been conducted among Filipino immigrants in the Northeastern part of the United States. To determine hypertension prevalence and risk factors among Filipino Americans in the New York City area, blood pressure and other clinical measurements were taken from a sample of Filipino Americans during 119 community health screenings conducted between 2006 and 2010. Additional socio-demographic and health-related characteristics were also collected via a cross-sectional survey. A total of 1,028 Filipino immigrants completed the survey and had clinical readings collected. Bivariate analyses and logistic regression were performed in order to predict and assess risk factors for hypertension among our sample. Fifty-three percent of individuals were hypertensive, and half of hypertensive individuals were uninsured. Logistic regression indicated that older age, male gender, living in the United States for over 5 years, a BMI greater than 23.0 kg/m2, an elevated glucose reading, a family history of hypertension, and fair or poor self-reported health status were predictors of hypertension. There is a great need to develop more effective community-based interventions in the Filipino community to address cardiovascular health disparities.  相似文献   
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Kamath S  Sahni S  Ranka S  Li J  Palta J 《Medical physics》2004,31(12):3314-3323
The multileaf travel range limitations on some linear accelerators require the splitting of a large intensity-modulated field into two or more adjacent abutting intensity-modulated subfields. The abutting subfields are then delivered as separate treatment fields. This workaround not only increases the treatment delivery time but it also increases the total monitor units (MU) delivered to the patient for a given prescribed dose. It is imperative that the cumulative intensity map of the subfields is exactly the same as the intensity map of the large field generated by the dose optimization algorithm, while satisfying hardware constraints of the delivery system. In this work, we describe field splitting algorithms that split a large intensity-modulated field into two or more intensity-modulated subfields with and without feathering, with optimal MU efficiency while satisfying the hardware constraints. Compared to a field splitting technique (without feathering) used in a commercial planning system, our field splitting algorithm (without feathering) shows a decrease in total MU of up to 26% on clinical cases and up to 63% on synthetic cases.  相似文献   
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