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Two cases of unusual benign tumors of the neck are described, both of which were initially misdiagnosed on cytology as carcinomas. Fine-needle aspiration findings in each case demonstrated a pleomorphic population of cells including bizarre multi-nucleated giant cells, the latter raising the false impression of malignancy. However, on review the cytological appearances of the tumors, a pleomorphic lipoma and a carotid body tumor, were characteristic. the correct diagnosis in each case would have been made or suggested if the pathologist had been familiar with the cytologic features characteristic of the lesion and the differential diagnosis of the head and neck tumors. in addition, the point is made that adequate clinical information is essential for the pathologist if all relevant conditions are not to be missed in the differential diagnosis.  相似文献   
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Caenorhabditis elegans let-7, a founding member of the microRNA family, is predicted to bind to six sites in the 3'UTR of the mRNA of its target gene, lin-41, to down-regulate LIN-41. Here, we demonstrate that wild-type let-7 microRNA binds in vitro to RNA from the lin-41 3'UTR. This interaction is dependent on two conserved let-7 complementary sites (LCSs). A 27-nucleotide sequence between the LCSs is also necessary for down-regulation in vivo. LCS mutations compensatory to the lesion in let-7(n2853) can partially restore lin-41 3'UTR function in a let-7(n2853) background, providing the first experimental evidence for an animal miRNA binding directly to its validated target in vivo.  相似文献   
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PURPOSE: The melanoma cellular adhesion molecule, also known as MUC18, is highly expressed on several tumors, including bone sarcomas. The level of MUC18 expression has been found to correlate directly with tumor progression and metastatic potential. These observations have established MUC18 as a candidate mediator of tumor growth and metastasis, and suggest that blockade of MUC18 might be a potential target for immunotherapy against several MUC18-expressing tumors, including human bone sarcomas. EXPERIMENTAL DESIGN: To investigate whether blockade of MUC18 might be a potential target for immunotherapy against osteosarcoma, we have recently developed a fully human anti-MUC18 antibody, ABX-MA1. We studied the effect of ABX-MA1 on growth, adhesion, invasion, and metastasis of human osteosaroma cells both in vitro and in vivo. RESULTS: MUC18 was widely expressed on both osteosarcoma and Ewing's sarcoma cells. ABX-MA1 had no effect on the proliferation of osteosarcoma cells in vitro, nor did it significantly inhibit the growth of KRIB human osteosarcoma cells when they were orthotopically implanted into the tibias of nude mice. However, after 6 weeks, significantly fewer ABX-MA1-treated mice developed spontaneous pulmonary metastases than did IgG-treated control mice. Additionally, ABX-MA1 decreased the invasion of osteosarcoma cells through Matrigel-coated filters and disrupted homotypic adhesion between osteosarcoma cells and their heterotypic interaction with human vascular endothelial cells. CONCLUSIONS: Our findings demonstrate that MUC18 plays a central role in the metastasis of osteosarcoma and suggest that targeted inhibition of this antigen by ABX-MA1 may be a novel immunotherapeutic approach in the management of this tumor.  相似文献   
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The Effect of Area HMO Market Share on Cancer Screening   总被引:2,自引:1,他引:2       下载免费PDF全文
Objective. Managed care may have widespread impacts on health care delivery for all patients in the areas where they operate. We examine the relationship between area managed care activity and screening for breast, cervical, and prostate cancer among patients enrolled in more managed care plans and patients who are enrolled in less managed plans.
Data and Methods. Data on cancer screening from the 1996 Medical Expenditure Panel Survey (MEPS) were linked to data on health maintenance organization (HMO) and preferred provider organization (PPO) market share and HMO competition at the metropolitan statistical area (MSA) level. Logistic regression analysis was used to examine the relationship between area managed care prevalence and the use of mammography, clinical breast examination, Pap smear, and prostate cancer screening in the past two years, controlling for important covariates.
Results. Among all patients, increases in area-level HMO market share are associated with increases in the appropriate use of mammography, clinical breast exam, and Pap smear (OR for high relative to low managed care areas are 1.75, p <.01, for mammography, 1.58, p <.05, for clinical breast exam, and 1.71, p <.01, for Pap smear). In analyses of subgroups, the relationship is significant only for individuals who are enrolled in the nonmanaged plans; there is no relationship for individuals in more managed plans. No relationship is observed between area HMO market share and prostate cancer screening in any analysis. Neither the level of competition between area HMOs nor area PPO market share is associated with screening rates.
Conclusions. Area-level managed care activity can influence preventive care treatment patterns.  相似文献   
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ABSTRACT

Purpose/Aim: Cementogenesis is a critical step in periodontal tissue regeneration given the essential role of cementum in anchoring teeth to the alveolar bone. This study is designed to achieve integrated cementum formation on the root surfaces of human teeth using growth factor–releasing scaffolds with periodontal ligament stem/progenitor cells (PDLSCs). Materials and methods: Human PDLSCs were sorted by CD146 expression, and characterized using CFU-F assay and induced multi-lineage differentiation. Polycaprolactone scaffolds were fabricated using 3D printing, embedded with poly(lactic-co-glycolic acids) (PLGA) microspheres encapsulating connective tissue growth factor (CTGF), bone morphogenetic protein-2 (BMP-2), or bone morphogenetic protein-7 (BMP-7). After removing cementum on human tooth roots, PDLSC-seeded scaffolds were placed on the exposed dentin surface. After 6-week culture with cementogenic/osteogenic medium, cementum formation and integration were evaluated by histomorphometric analysis, immunofluorescence, and qRT-PCR. Results: Periodontal ligament (PDL) cells sorted by CD146 and single-cell clones show a superior clonogenecity and multipotency as compared with heterogeneous populations. After 6 weeks, all the growth factor–delivered groups showed resurfacing of dentin with a newly formed cementum-like layer as compared with control. BMP-2 and BMP-7 showed de novo formation of tissue layers significantly thicker than all the other groups, whereas CTGF and BMP-7 resulted in significantly improved integration on the dentin surface. The de novo mineralized tissue layer seen in BMP-7-treated samples expressed cementum matrix protein 1 (CEMP1). Consistently, BMP-7 showed a significant increase in CEMP1 mRNA expression. Conclusion: Our findings represent important progress in stem cell–based cementum regeneration as an essential part of periodontium regeneration.  相似文献   
17.
Recently, one of the world’s leading scientific and technical advisory groups, the U.S. President’s Council of Advisors on Science and Technology (or PCAST), published an assessment of the research supporting several forensic science procedures in regular use. PCAST was particularly interested in pattern recognition or comparison procedures, specifically: simple and mixed DNA profiles; bite marks; latent fingerprints; firearms; footwear; and hair analysis. In its report and recommendations PCAST emphasised the primacy of validation. In response, the Council of the Australian and New Zealand Forensic Science Society produced a short statement suggesting that the PCAST report has limited application to forensic science in Australia and New Zealand. This short commentary offers an alternative perspective.  相似文献   
18.
This study examined the efficacy of Collaborative & Proactive Solutions (CPS) in treating oppositional defiant disorder (ODD) in youth by comparing this novel treatment to Parent Management Training (PMT), a well-established treatment, and a waitlist control (WLC) group. One hundred thirty-four youth (ages 7–14, 61.9% male, 83.6% White) who fulfilled Diagnostic and Statistical Manual of Mental Disorders (4th ed.) criteria for ODD were randomized to CPS, PMT, or WLC groups. ODD was assessed with semistructured diagnostic interviews, clinical global severity and improvement ratings, and parent report measures. Assessments were completed pretreatment, posttreatment, and at 6 months following treatment. Responder and remitter analyses were undertaken using intent-to-treat mixed-models analyses. Chronological age, gender, and socioeconomic status as well as the presence of comorbid attention deficit/hyperactivity and anxiety disorders were examined as predictors of treatment outcome. Both treatment conditions were superior to the WLC condition but did not differ from one another in either our responder or remitter analyses. Approximately 50% of youth in both active treatments were diagnosis free and were judged to be much or very much improved at posttreatment, compared to 0% in the waitlist condition. Younger age and presence of an anxiety disorder predicted better treatment outcomes for both PMT and CPS. Treatment gains were maintained at 6-month follow-up. CPS proved to be equivalent to PMT and can be considered an evidence-based, alternative treatment for youth with ODD and their families.  相似文献   
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