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排序方式: 共有739条查询结果,搜索用时 15 毫秒
1.
Ying Qian Pedram Hamrah Florence Boisgerault Satoru Yamagami Sudhir Vora Gilles Benichou M Reza Dana 《Journal of interferon & cytokine research》2002,22(12):1217-1225
This study aimed to determine the effects of anti-CD154 on T cell cytokine profiles and ocular chemokine gene expression after high-risk corneal transplantation and to specifically determine if CD154 blockade is associated with a switch from a Th1 to a Th2 alloimmune response. Mice were used as recipients of syngeneic or multiple minor H or MHC antigen-mismatched corneal grafts. Recipient beds were neovascularized (high-risk). Hosts were randomized to receive either anti-CD154 antibody or control immunoglobulin (Ig) perioperatively. Two weeks after corneal transplantation, allospecific delayed-type hypersensitivity (DTH) was evaluated. Frequencies of interferon-gamma (IFN-gamma)-, interleukin-2 (IL-2)-, IL-4-, and IL-5-secreting T cells in the hosts were measured by enzyme-linked immunospot (ELISPOT) assay. Ocular chemokine gene expression in anti-CD154-treated and control hamster Ig-treated groups was determined using a multiprobe ribonuclease protection assay (RPA). Leukocyte infiltration of corneal grafts was evaluated microscopically. Anti-CD154-treated mice did not exhibit allospecific DTH. The frequencies of Th1 cytokine-producing but not Th2 cytokine-producing T cells were significantly reduced in anti-CD154-treated hosts. Postoperative mRNA levels of RANTES and macrophage inflammatory protein-1beta (MIP-1beta) in anti-CD154-treated eyes were substantially suppressed compared with hamster Ig-treated controls. Leukocyte infiltration was profoundly suppressed in grafts of anti-CD154-treated hosts. These data demonstrate that blockade of the CD40-CD154 costimulatory pathway after corneal transplantation inhibits Th1-mediated responses but does not induce a switch to a Th2-specific response. In addition, anti-CD154 therapy suppresses ocular chemokine gene expression and leukocytic infiltration into allografts. 相似文献
2.
Swartz MJ Batra SK Varshney GC Hollingsworth MA Yeo CJ Cameron JL Wilentz RE Hruban RH Argani P 《American journal of clinical pathology》2002,117(5):791-796
Pancreatic adenocarcinoma is believed to develop from histologically identifiable intraductal lesions known as pancreatic intraepithelial neoplasias (PanINs) that undergo a series of architectural, cytologic, and genetic changes, a progression model similar to the adenoma-carcinoma sequence in the colon. The apomucin MUC4 has been implicated in invasive pancreatic adenocarcinoma. MUC4 expression is not detectable at the RNA level in normal pancreas but is detectable at high levels in invasive pancreatic adenocarcinoma. We documented the pattern of expression of MUC4 in PanINs by studying a series of 71 PanIN lesions immunohistochemically using a new monoclonal antibody to MUC4. Five (17%) of 30 PanIN-1 lesions, 10 (36%) of 28 PanIN-2 lesions, 11 (85%) of 13 PanIN-3 lesions, and 25 (89%) of 28 invasive adenocarcinomas labeled with the MUC4 antibody used in the study. In addition, afew nonneoplastic lesions labeled with the MUC4 antibody, including reactive ducts in chronic pancreatitis, atrophic ducts filled with inspissated secretions, and ducts showing squamous metaplasia. Our data help establish the patterns of MUC4 expression in neoplastic precursors in the pancreas and add further support to the progression model for pancreatic adenocarcinoma. 相似文献
3.
Telomere lengths of translocation-associated and nontranslocation-associated sarcomas differ dramatically
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Montgomery E Argani P Hicks JL DeMarzo AM Meeker AK 《The American journal of pathology》2004,164(5):1523-1529
Sarcomas can be divided into those with specific translocations displaying monotonous cytomorphology, and those with complex karyotypes and marked cellular pleomorphism. Telomeres contain terminal DNA sequence repeats that maintain chromosomal stability. Telomeres shorten with cell division and may become dysfunctional leading to chromosomal instability. Using a fluorescence in situ hybridization/immunofluorescence method to assess telomere lengths in archival tissues we analyzed these two types of sarcomas using paraffin-embedded primary tumor specimens. Tissues from nine sarcomas with characteristic translocations (two synovial sarcomas, two alveolar rhabdomyosarcomas, two desmoplastic round cell tumors, and one each of infantile fibrosarcoma, myxoid liposarcoma, cellular congenital mesoblastic nephroma) and nine without (four malignant fibrous histiocytomas, two leiomyosarcomas, one pleomorphic rhabdomyosarcoma, one dedifferentiated chondrosarcoma, and one malignant peripheral nerve sheath tumor) were analyzed. In all (nine of nine) cases with specific translocations, which generally have few karyotypic abnormalities, telomere lengths were similar to or reduced compared to surrounding nonneoplastic tissues. In contrast, telomeres in cases lacking specific translocations, which generally contain complex karyotypes, were often found to be dramatically lengthened and heterogeneous. In addition to markedly elongated telomeres, seven of nine (78%) complex cases exhibited large brightly stained regions corresponding to a specific type of promyelocytic leukemia nuclear body found in immortalized cells that maintain telomeres in a telomerase-independent manner [alternative lengthening of telomeres (ALT) pathway]. This phenotype is unlike that of epithelial neoplasms that typically display complex karyotypes with abnormally short telomeres maintained by the enzyme telomerase. The discovery of heterogeneous telomere lengths and evidence of the ALT pathway in the majority of sarcomas with complex karyotypes supports the existence of a telomere maintenance pathway incapable of full karyotypic stabilization in pleomorphic sarcomas. These findings provide additional molecular-genetic evidence supporting the dichotomous grouping of sarcomas into those with characteristic signature translocations without extensive additional karyotypic abnormalities, and those without such signature translocations that typically display very complex karyotypes, and point to telomere dysfunction as a plausible contributor to the chromosomal aberrations found in complex sarcomas. 相似文献
4.
The V599E BRAF mutation is uncommon in biliary tract cancers. 总被引:1,自引:0,他引:1
David Goldenberg Eli Rosenbaum Pedram Argani Ignacio I Wistuba David Sidransky Paul J Thuluvath Manuel Hidalgo Joseph Califano Anirban Maitra 《Modern pathology》2004,17(11):1386-1391
Activating point mutations of the BRAF oncogene have been identified in several solid tumors, most commonly in cutaneous melanomas and papillary carcinomas of the thyroid. A specific point mutation--V599E--accounts for the overwhelming majority of these mutational events. We explored the frequency of the V599E BRAF mutation in biliary tract cancers. In all, 62 archival biliary tract cancers, including 15 gallbladder cancers, 15 extrahepatic, and 10 intrahepatic cholangiocarcinomas from the United States, and 22 gallbladder carcinomas from Chile were analyzed for the V599E mutation of the BRAF gene using three distinct methods: direct sequencing, a primer extension method (Mutector assay), and the highly sensitive quantitative Gap Ligase Chain Reaction. The common V599E mutation was not identified in any of the 62 biliary cancer samples using these three methods of detection. The V599E somatic mutation of the BRAF gene is absent in biliary tract cancers, at least in the two geographic populations (United States and Chile) examined. Activation of the RAS/RAF/MAP kinase pathway in biliary tract cancers is likely to be secondary to oncogenic RAS mutations, or due to mutations of the BRAF gene at nucleotide positions not explored in the current study. 相似文献
5.
OBJECTIVES: Portfolio theory has been suggested as a means to improve the risk-return characteristics of investments in health-care programs through diversification when costs and effects are uncertain. This approach is based on the assumption that the investment proportions are not subject to uncertainty and that the budget can be invested in toto in health-care programs. METHODS: In the present paper we develop an algorithm that accounts for the fact that investment proportions in health-care programs may be uncertain (due to the uncertainty associated with costs) and limited (due to the size of the programs). The initial budget allocation across programs may therefore be revised at the end of the investment period to cover the extra costs of some programs with the leftover budget of other programs in the portfolio. RESULTS: Once the total budget is equivalent to or exceeds the expected costs of the programs in the portfolio, the initial budget allocation policy does not impact the risk-return characteristics of the combined portfolio, i.e., there is no benefit from diversification anymore. CONCLUSION: The applicability of portfolio methods to improve the risk-return characteristics of investments in health care is limited to situations where the available budget is much smaller than the expected costs of the programs to be funded. 相似文献
6.
Review on the Oncology Practice in the Midst of COVID-19 Crisis: The Challenges and Solutions
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Pedram FadaviMohammad HoushyariAmir Shahram Yousefi Kashi Alireza Mosavi JarrahiFarnaz Roshanmehr Mohammad Ali BroomandSaleh SandoughdaranFarzad Taghizadeh-Hesary 《Asian Pacific journal of cancer prevention》2021,22(1):19-24
As of late 2019, the outbreak of novel coronavirus disease (COVID-19) –that started in China– has rapidly afflicted all over the world. The COVID-19 pandemic has challenged health-care facilities to provide optimal care. In this context, cancer care requires special attention because of its peculiar status by including patients who are commonly immunocompromised and treatments that are often highly toxic. In this review article, we have classified the main impacts of the COVID-19 pandemic on oncology practices –followed by their solutions– into ten categories, including impacts on (1) health care providers, (2) medical equipment, (3) access to medications, (4) treatment approaches, (5) patients’ referral, (6) patients’ accommodation, (7) patients’ psychological health, (8) cancer research, (9) tumor board meetings, and (10) economic income of cancer centers. The effective identification and management of all these challenges will improve the standards of cancer care over the viral pandemic and can be a practical paradigm for possible future crises. 相似文献
7.
8.
Christine T. Kovner Maja Djukic Jin Jun Jason Fletcher Farida K. Fatehi Carol S. Brewer 《Nursing outlook》2018,66(2):160-167
Background
The Institute of Medicine (IOM) report, The Future of Nursing, included recommendations to increase nurse diversity, the percent of nurses obtaining a bachelor’s degree, and inter-professional education.Purpose
The purpose of this paper is to report the progress toward achievement of these recommendations.Methods
We used a longitudinal, multi-state data from four cohorts of nurses newly licensed in 2004 to 2005, 2007 to 2008, 2010 to 2011, and 2014 to 2015 to examine and compare the trends.Finding
The percentage of males who became licensed increased, from 8.8% in 2004 to 2005 cohort to 13.6% in the 2014 to 2015 cohort. The percentage of white-non-Hispanic nurses who were licensed decreased from 78.9% in 2007 to 2008 to 73.8% in 2014 to 2015. These differences primarily reflect an increase in white-Hispanic nurses. More nurses are obtaining a bachelor’s degree as their first professional degree, from 36.6% in 2004 to 2005 cohort to 48.5% in 2014 to 2015 cohort. About 40% of the 2014 to 2015 cohort reported that they learned to work in inter-professional teams. Collegial nurse-physician relations had an upward positive trajectory over time increasing almost 7%.Discussion
The diversity and education of new nurses have increased, but are short of meeting the IOM recommendations. 相似文献9.
The concept of food addiction (FA) is a potentially important contributing factor to the development of obesity in the general population; however, little is known about the hormonal and dietary differences between obesity with and without FA. Therefore, the aim of our study was to explore potential biomarkers, including various hormones and neuropeptides, which regulate appetite and metabolism, and dietary components that could potentially differentiate obesity with and without FA. Of the 737 adults recruited from the general Newfoundland population, 58 food-addicted and non-food-addicted overweight/obese individuals (FAO, NFO) matched for age, sex, BMI and physical activity were selected. A total of 34 neuropeptides, gut hormones, pituitary polypeptide hormones and adipokines were measured in fasting serum. We found that the FAO group had lower levels of TSH, TNF-α and amylin, but higher levels of prolactin, as compared to NFO group. The total calorie intake (per kg body weight), the dietary intake of fat (per g/kg body weight, per BMI and per percentage of trunk fat) and the percent calorie intake from fat and carbohydrates (g/kg) was higher in the FAO group compared to the NFO group. The FAO subjects consumed more sugar, minerals (including sodium, potassium, calcium and selenium), fat and its components (such as saturated, monounsaturated and trans fat), omega 3 and 6, vitamin D and gamma-tocopherol compared to the NFO group. To our knowledge, this is the first study indicating possible differences in hormonal levels and micro-nutrient intakes between obese individuals classified with and without food addiction. The findings provide insights into the mechanisms by which FA could contribute to obesity. 相似文献
10.