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Merritt JL Davis DM Pittelkow MR Babovic-Vuksanovic D 《American journal of medical genetics. Part A》2006,140(15):1669-1672
Acrochordons are frequently encountered benign skin lesions that may occasionally represent underlying pathology. Pancreatic islet-cell tumors are rare neoplasms and few cases have been described in patients with tuberous sclerosis complex (TSC). A 39-year-old man presenting in acute renal failure was referred to us for further diagnostic evaluation of coincidentally noted dysmorphic features. Physical examination revealed over 1,000 acrochordons in addition to findings meeting criteria for TSC. The diagnosis was confirmed by disclosure of mutation in the TSC2 gene. Further evaluation revealed pancreatic islet cell tumors. Acrochordons are a common skin lesion, but when presenting in an atypical manner or unusual number may be a sign of TSC and underlying occult pathology thereby warranting evaluation of TSC2. Additionally, mutations in TSC2 gene may be a risk factor for developing pancreatic islet-cell tumors. 相似文献
54.
Jonathan Ophir S. Kaisar Alam Brian S. Garra Faouzi Kallel Elisa E. Konofagou Thomas Krouskop Christopher R. B. Merritt Raffaella Righetti Remi Souchon Seshadri Srinivasan Tomy Varghese 《Journal of Medical Ultrasonics》2002,29(4):155-171
Elastography is a method that can ultimately generate several new kinds of images, called elastograms. As such, all the properties
of elastograms are different from the familiar properties of sonograms. While sonograms convey information related to the
local acoustic backscatter energy from tissue components, elastograms relate to its local strains, Young's moduli or Poisson's
ratios. In general, these elasticity parameters are not directly correlated with sonographic parameters, i.e. elastography
conveys new information about internal tissue structure and behavior under load that is not otherwise obtainable. In this
paper we summarize our work in the field of elastography over the past decade. We present some relevant background material
from the field of biomechanics. We then discuss the basic principles and limitations that are involved in the production of
elastograms of biological tissues. Results from biological tissues in vitro and in vivo are shown to demonstrate this point.
We conclude with some observations regarding the potential of elastography for medical diagnosis. 相似文献
55.
Roentgenographic evaluation of the augmented breast. 总被引:1,自引:0,他引:1
K P Douglas E I Bluth E R Sauter W M McKinnon R B Bergeron C R Merritt M A Sullivan J M Finley 《Southern medical journal》1991,84(1):49-54
We performed a retrospective study to determine the sensitivity of mammography in detecting breast cancer arising in women with augmented breasts. Of eight women with breast implants in whom breast cancer developed, six had mammograms before biopsy. Only two of the six cancers were identified mammographically (sensitivity = 33%), and one of these two was seen only in retrospect. In both cases, the mammographic findings suggested a benign rather than a malignant process. All eight women had a palpable mass and early disease, and all are clinically disease-free at present. The sensitivity of mammography in detecting palpable cancers in a control group of women without implants was 92% (118 of 128). For tumors of 2 cm or less, the sensitivity was 88% (58 of 66). These results suggest that the sensitivity of mammography in detecting breast cancer is decreased when implants are present. Further investigations are needed to determine the effects of prostheses on mammographic evaluations. 相似文献
56.
DNA binding to human leukocytes. Evidence for a receptor-mediated association, internalization, and degradation of DNA. 总被引:19,自引:5,他引:19 下载免费PDF全文
Previous studies have indicated that white blood cells possess DNA on their outer membranes. In this study we set out to determine whether exogenous DNA bound to cells in a fashion compatible with a ligand receptor union. Purified populations of white blood cells; neutrophils (polymorphonuclear leukocytes, PMN), adherent mononuclear cells (ADMC), rosetting lymphocytes (E+ cells), and nonrosetting lymphocytes (E- cells) were incubated with radiolabeled lambda phage DNA in increasing concentrations. Binding of [3H]DNA was a saturable process and was inhibited by excess cold DNA and prior trypsinization of the cells. Rate zonal density centrifugation of purified cell membrane preparations confirmed that DNA was binding to the outer cell surface. The dissociation constant for all four cell types was approximately 10(-9) M, and from 0.81 X 10(3) to 2.6 X 10(3) molecules of lambda phage DNA bound to each cell depending upon cell type. Binding was not competitively inhibited by RNA, polydeoxyadenylic acid-polydeoxythymidylic acid (poly [d(A).d(T)]), or mononucleotides. Sodium dodecyl sulfate (SDS) polyacrylamide gel electrophoresis (PAGE)-separated proteins from PMN, ADMC, E+, and E- cells were electrophoretically blotted onto nitrocellulose sheets; a probe of biotin-labeled DNA indicated a single species of DNA-binding molecule migrating in a position consistent with a molecular weight of 30,000. Isotopic and immunofluorescent studies indicate that DNA is internalized and degraded to oligonucleotides; this process is inhibited by cycloheximide. These results support the notion that there is a common binding site for DNA on white blood cells, that the stoichiometry of the association is compatible with a ligand receptor relationship, and that this apparent receptor is responsible for the endocytosis and degradation of exogenous DNA. 相似文献
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Rowena Merritt Sally Kendall Tamsyn Eida Fiona Dykes Rafael Pérez-Escamilla 《Maternal & child nutrition》2023,19(Z1):e13443
Breastfeeding is the most accessible and cost-effective activity available to public health and has been shown to be one of the most effective preventive measures mothers can take to protect their children's health. Despite the well-documented benefits, the UK has one of the lowest breastfeeding rates in the world. The Becoming Breastfeeding Friendly (BBF) toolkit was developed through highly structured technical and academic collaboration, led by Yale University. It provides an evidence-based process to help countries assess their breastfeeding status and readiness to scale up, and identifies concrete measures countries can take to sustainably increase breastfeeding rates, based on data-driven recommendations. BBF is grounded in the Breastfeeding Gear Model complex adaptive systems framework which is made up of eight simultaneous conditions that sustain breastfeeding. In 2018, a committee of multi-agency stakeholders implemented the BBF process in England, collecting evidence to score the ‘gear’ components of England's breastfeeding environment against 54 benchmarks. The Training and Programme Delivery gear received the highest score, attributable to existing learning outcomes for health professionals and practitioners, peer supporters and specialist services, although there is a need for greater coordination and integration. The lowest scores were given for Promotion and Coordination, Goals and Monitoring due to the lack of a dedicated national strategy for breastfeeding and poor sharing of localised strategies and programmes. The process generated clear recommendations highlighting the need for more robust routine infant feeding data collection and reporting, and the necessity for strengthening leadership, monitoring and oversight to scale up and sustain breastfeeding. 相似文献
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Illicit substance use, especially of inhalants, is a public health crisis during adolescence, particularly for maltreated youths. This study advances the literature by highlighting the prevalence of inhalant use among child welfare–involved adolescents. Using the National Survey of Child and Adolescent Well-Being (NSCAW) II data set, case-status factors, problem behaviors, deviant peers, delinquency, depression, and school peer engagement were inspected using logistic regression. Females, delinquency, deviant peers, problematic behaviors, and depression are positively related to inhalant use, whereas youth school peer engagement mitigates inhalant use. Attention to peer relationships and psychosocial risk factors is necessary for adolescents. 相似文献