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排序方式: 共有1469条查询结果,搜索用时 15 毫秒
1.
A new case of pulmonary hemosiderosis with coeliac disease is reported. This is an extremely rare combination of which only nine instances have been published over the last 20 years. Three of the reported cases occurred in children. Apart from a marked predominance of males, the combination has no specific features. Firm evidence of a causal relationship between the two diseases is lacking but treatment with a gluten-free diet alone apparently had beneficial effects on the lung disease in two patients. Three pathogenic hypotheses are discussed herein: deposition of circulating immune complexes involving food allergens on the basement membrane of alveolar capillaries; reaction between antireticulin antibodies and an alveolar basement membrane antigen; or effect of adenovirus 12, a potential causative factor for celiac disease. Patients with idiopathic pulmonary hemosiderosis should routinely have tests for gluten intolerance, for instance a lactulose-mannitol intestinal permeability test. Lastly, other concomitant food allergies are reported. 相似文献
2.
Hayley S. Mountford Dorothy V. M. Bishop Paul A. Thompson Nuala H. Simpson Dianne F. Newbury 《American journal of medical genetics. Part C, Seminars in medical genetics》2020,184(2):256-266
Sex chromosome trisomies (SCTs) (XXX, XXY, and XYY karyotypes) are associated with an elevated risk of neurodevelopmental disorders. The range of severity of the phenotype is substantial. We considered whether this variable outcome was related to the presence of copy number variants (CNVs)—stretches of duplicated or deleted DNA. A sample of 125 children with an SCT were compared with 181 children of normal karyotype who had been given the same assessments. First, we compared the groups on measures of overall CNV burden: number of CNVs, total span of CNVs, and likely functional impact (probability of loss‐of‐function intolerance, pLI, summed over CNVs). Differences between groups were small relative to within‐group variance and not statistically significant on overall test. Next, we considered whether a measure of general neurodevelopmental impairment was predicted by pLI summed score, SCT versus comparison group, or the interaction between them. There was a substantial effect of SCT/comparison status but the pLI score was not predictive of outcomes in either group. We conclude that variable presence of CNVs is not a likely explanation for the wide phenotypic variation in children with SCTs. We discuss methodological challenges of testing whether CNVs are implicated in causing neurodevelopmental problems. 相似文献
3.
Alexander S. Graphodatsky Polina L. Perelman Natalya V. Sokolovskaya Violetta R. Beklemisheva Natalya A. Serdukova Gauthier Dobigny Stephen J. O’Brien Malcolm A. Ferguson-Smith Fengtang Yang 《Chromosome research》2008,16(1):129-143
Canid species (dogs and foxes) have highly rearranged karyotypes and thus represent a challenge for conventional comparative
cytogenetic studies. Among them, the domestic dog is one of the best-mapped species in mammals, constituting an ideal reference
genome for comparative genomic study. Here we report the results of genome-wide comparative mapping of dog chromosome-specific
probes onto chromosomes of the dhole, fennec fox, and gray fox, as well as the mapping of red fox chromosome-specific probes
onto chromosomes of the corsac fox. We also present an integrated comparative chromosome map between the species studied here
and all canids studied previously. The integrated map demonstrates an extensive conservation of whole chromosome arms across
different canid species. In addition, we have generated a comprehensive genome phylogeny for the Canidae on the basis of the
chromosome rearrangements revealed by comparative painting. This genome phylogeny has provided new insights into the karyotypic
relationships among the canids. Our results, together with published data, allow the formulation of a likely Canidae ancestral
karyotype (CAK, 2n = 82), and reveal that at least 6–24 chromosomal fission/fusion events are needed to convert the CAK karyotype
to that of the modern canids.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
4.
Dark ML Perelman LT Itzkan I Schaffer JL Field MS 《Physics in medicine and biology》2000,45(2):529-539
Knee meniscus is a hydrated tissue; it is a fibrocartilage of the knee joint composed primarily of water. We present results of interferometric surface monitoring by which we measure physical properties of human knee meniscal cartilage. The physical response of biological tissue to a short laser pulse is primarily thermomechanical. When the pulse is shorter than characteristic times (thermal diffusion time and acoustic relaxation time) stresses build and propagate as acoustic waves in the tissue. The tissue responds to the laser-induced stress by thermoelastic expansion. Solving the thermoelastic wave equation numerically predicts the correct laser-induced expansion. By comparing theory with experimental data, we can obtain the longitudinal speed of sound, the effective optical penetration depth and the Grüneisen coefficient. This study yields information about the laser tissue interaction and determines properties of the meniscus samples that could be used as diagnostic parameters. 相似文献
5.
Leah R. Ketcheson Erin E. Centeio Erin E. Snapp Hayley B. McKown Jeffrey J. Martin 《Disability and health journal》2021,14(1):100952
BackgroundChildren with intellectual and developmental disabilities (IDD) often experience increased barriers to engaging in physical activity (PA) which can stem from lack of gross motor function (GMF) development. Intervening on GMF at an early age can create better opportunities for children with IDD to engage in regular PA. In turn, increased PA can improve health outcomes and increase social skills.ObjectiveThe primary objective of this pilot study was to explore the effectiveness of a community-based GMF-focused PA intervention for improving overall motor skills and PA for children with IDD.MethodsAll study participants (n = 24) engaged in 10 weeks of programming for 1 h each week. A convenience sample was utilized.ResultsResults indicated no statistically significant changes pre to post for motor skill scores. However, a visual analysis of mean changes showed a consistent pattern of increased scores from pre to post on most skills. Additionally, we found that a change in participant locomotor skills significantly predicted change in Moderate to Vigorous Physical Activity (MVPA), F (1,11) = 5.16, Adj R2 = .26, p = .04.ConclusionsThese results suggest individualized attention on GMF may help to increase motor skills for children with IDD. This study adds to the small but growing amount of research examining the efficacy of community based adapted PA interventions. Further, study results should support continued exploration of effective approaches to address the motor delays experienced by children with IDD. 相似文献
6.
Jim Maas Garry Barton Vivienne Maskrey Hayley Pinto Richard Holland 《Drug and alcohol dependence》2013
Background
The cost of opiate substitution is usually considered lower in cost when methadone is used, as compared to that of buprenorphine, however the overall cost effectiveness of substitution programmes comparing the two drugs remains largely unknown.Methods
We evaluated the treatment cost and effectiveness of methadone and buprenorphine when used in an opiate substitution programme in Norfolk, UK. All programme costs, estimated from the perspective of the drug treatment clinic, were collected on 361 opiate-dependent participants over a six-month period. Total costs comprised medication (methadone or buprenorphine) costs, pharmacy supervision and dispensing costs, and drug service clinic costs. Effectiveness was measured in terms of (1) each programmes ability to retain participants in the programme for six months, and (2) the ability of the programme to accomplish complete abstinence from illicit opiate consumption.Results
Overall, mean medication-only costs of methadone were lower than that of buprenorphine, however, pharmacy and clinic costs were lower for the buprenorphine programme. The covariate-adjusted mean total cost of the two programmes was not significantly different. Mean six-month retention rates were higher on the methadone programme, therefore, the methadone programme “dominates” the buprenorphine programme as it was slightly more effective for the same cost. Conversely, when ability to stop taking illicit opiates concomitant with opiate substitution medication was considered, the buprenorphine programme was more effective with an additional cost of £903 per individual who stopped illicit opiate use.Conclusions
The provision of buprenorphine should be considered an appropriate treatment if cessation of illicit opiate use, concomitant with programme retention is considered an important outcome. 相似文献7.
8.
Yu Sun Hayley Reynolds Darren Wraith Scott Williams Mary E. Finnegan Catherine Mitchell Declan Murphy Martin A. Ebert Annette Haworth 《Australasian physical & engineering sciences in medicine / supported by the Australasian College of Physical Scientists in Medicine and the Australasian Association of Physical Sciences in Medicine》2017,40(1):39-49
The performance of a support vector machine (SVM) algorithm was investigated to predict prostate tumour location using multi-parametric MRI (mpMRI) data. The purpose was to obtain information of prostate tumour location for the implementation of bio-focused radiotherapy. In vivo mpMRI data were collected from 16 patients prior to radical prostatectomy. Sequences included T2-weighted imaging, diffusion-weighted imaging and dynamic contrast enhanced imaging. In vivo mpMRI was registered with ‘ground truth’ histology, using ex vivo MRI as an intermediate registration step to improve accuracy. Prostate contours were delineated by a radiation oncologist and tumours were annotated on histology by a pathologist. Five patients with minimal imaging artefacts were selected for this study. A Gaussian kernel SVM was trained and tested on different patient data subsets. Parameters were optimised using leave-oneout cross validation. Signal intensities of mpMRI were used as features and histology annotations as true labels. Prediction accuracy, as well as area under the curve (AUC) of the receiver operating characteristics (ROC) curve, were used to assess performance. Results demonstrated the prediction accuracy ranged from 70.4 to 87.1% and AUC of ROC ranged from 0.81 to 0.94. Additional investigations showed the apparent diffusion coefficient map from diffusion weighted imaging was the most important imaging modality for predicting tumour location. Future work will incorporate additional patient data into the framework to increase the sensitivity and specificity of the model, and will be extended to incorporate predictions of biological characteristics of the tumour which will be used in bio-focused radiotherapy optimisation. 相似文献
9.
10.