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排序方式: 共有348条查询结果,搜索用时 15 毫秒
341.
Russell WB Fayers Tee S Lim Marek F Havlat 《Journal of Medical Imaging and Radiation Oncology》2016,60(5):693-695
We present a case of pulmonary sclerosing pneumocytoma (PSP) – (Formerly known as pulmonary sclerosing haemangioma) which was successfully treated with definitive radical external beam radiation therapy (EBRT). To our knowledge, such a treatment response has not been described in the literature. 相似文献
342.
The cell response to virus infection and virus perturbation of that response is dynamic and is reflected by changes in cell susceptibility to infection. In this study, we evaluated the response of human epithelial cells to sequential infections with human respiratory syncytial virus strains A2 and B to determine if a primary infection with one strain will impact the ability of cells to be infected with the second as a function of virus strain and time elapsed between the two exposures. Infected cells were visualized with fluorescent markers, and location of all cells in the tissue culture well were identified using imaging software. We employed tools from spatial statistics to investigate the likelihood of a cell being infected given its proximity to a cell infected with either the homologous or heterologous virus. We used point processes, K-functions, and simulation procedures designed to account for specific features of our data when assessing spatial associations. Our results suggest that intrinsic cell properties increase susceptibility of cells to infection, more so for RSV-B than for RSV-A. Further, we provide evidence that the primary infection can decrease susceptibility of cells to the heterologous challenge virus but only at the 16 h time point evaluated in this study. Our research effort highlights the merits of integrating empirical and statistical approaches to gain greater insight on in vitro dynamics of virus-host interactions. 相似文献
343.
Guthrie DM Pitman R Stolee P Strong G Poss J Tjam EY Bowman L Ashworth M Hirdes JP 《Journal of rehabilitation research and development》2011,48(5):545-554
This study assessed the reliability of the interRAI Community Health Assessment (interRAI CHA) and Deafblind Supplement (DbS). The interRAI CHA and DbS represents a multidimensional, standardized assessment instrument for use with adults (18 and older) who are deafblind. The interrater reliability of the instrument was tested through the completion of dual assessments with 44 individuals who were deafblind in the province of Ontario, Canada. Overall, nearly 50% of items had a kappa value of at least 0.60, indicating fair to substantial agreement for these items. Several items related to psychosocial well-being, mood, and sense of involvement had kappa scores of less than 0.40. However, among these items with low kappa values, most (78%) showed at least 70% agreement between the two assessors. The internal consistency of several health subscales, embedded within the assessment, was also very good and ranged from 0.63 to 0.93. The interRAI CHA and DbS represents a reliable instrument for assessing adults with deafblindness to better understand their needs, abilities, and preferences. 相似文献
344.
Bastiaan Evers Ewoud N Speksnijder Eva Schut Metamia Ciampricotti Matthew J Smalley Patrick WB Derksen Jos Jonkers Karin E de Visser 《The Journal of pathology》2010,220(1):34-44
The contribution of cancer cell‐intrinsic and ‐extrinsic factors to metastatic breast cancer is still poorly understood, hampering development of novel therapeutic strategies that decrease breast cancer mortality. Cre/loxP‐based conditional mouse models of breast cancer present unique opportunities to study sporadic tumour formation and progression in a controlled setting. Unfortunately, the generation of mouse strains carrying multiple mutant alleles needed for such studies is very time‐consuming. Moreover, conditional mouse tumour models do not permit independent manipulation of tumour cell‐intrinsic and ‐extrinsic factors. Although the latter can be achieved by cleared fat‐pad transplantation of mouse mammary epithelial cells (MMECs) from tumour suppressor gene (TSG) knockouts into wild‐type or mutant recipients, this procedure is not possible for mutations that cause embryonic lethality or preclude mammary gland development. Here we show that cleared fat‐pad transplantations with MMECs isolated from K14cre;Cdh1F/F; Trp53F/F mice expressing Cre recombinase under control of the cytokeratin‐14 promoter and carrying conditional null alleles for p53 and E‐cadherin (Cdh1) first resulted in the formation of phenotypically normal mammary glands, followed by the development of invasive metastatic mammary tumours. Tumour formation in the recipients mimicked tumour latency, spectrum, morphology, immunophenotype, and metastatic characteristics of the original mammary tumour model. This transplantation system, which can be expanded to other conditional TSG knockouts, permits independent genetic analysis of stromal factors and testing of additional cancer cell‐intrinsic mutations that would otherwise be embryonic lethal or require intensive breeding. Copyright © 2009 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd. 相似文献
345.
Understanding seasonal changes in age-related incidence of infections can be revealing for disentangling how host heterogeneities affect transmission and how to control the spread of infections between social groups. Seasonal forcing has been well documented in human childhood diseases but the mechanisms responsible for age-related transmission in free-living and socially structured animal populations are still poorly known. Here we studied the seasonal dynamics of Bordetella bronchiseptica in a free-living rabbit population over 5 years and discuss the possible mechanisms of infection. This bacterium has been isolated in livestock and wildlife where it causes respiratory infections that rapidly spread between individuals and persist as subclinical infections. Sera were collected from rabbits sampled monthly and examined using an ELISA. Findings revealed that B. bronchiseptica circulates in the rabbit population with annual prevalence ranging between 88% and 97%. Both seroprevalence and antibody optical density index exhibited 1-year cycles, indicating that disease outbreaks were seasonal and suggesting that long-lasting antibody protection was transient. Intra-annual dynamics showed a strong seasonal signature associated with the recruitment of naive offspring during the breeding period. Infection appeared to be mainly driven by mother-to-litter contacts rather than by interactions with other members of the community. By age 2 months, 65% of the kittens were seropositive. 相似文献
346.
本实验观察了MHDF对整体大鼠血流动力学和离体大鼠胸主动脉的作用。结果表明iv MHDF(3~12.8 mg/kg)能降低大鼠左心室±dp/dt_(max),V_(max),V_(pm)和LVSP,延长T-dp/dt_(max),减慢心率。MHDF还能舒张大鼠胸主动脉,ED_(50)为6.5×10~(-6)mol/L;非竞争拮抗NA和CaCl_2致主脉收缩,pD_2′为3.11±0.21和3.73±0.07;抑制高K~ 致主动脉收缩,IC_(50)为1.76×10~(-5)mol/L。提示MHDF对血管的作用与α受体阻断剂不同,而可能与钙拮抗有关。 相似文献
347.
Matthias Hoben Dr rer medic David B. Hogan MD Jeffrey W. Poss PhD Andrea Gruneir PhD Kim McGrail PhD Lauren E. Griffith PhD Stephanie A. Chamberlain PhD Carole A. Estabrooks PhD Colleen J. Maxwell PhD 《Journal of the American Geriatrics Society》2023,71(11):3467-3479
Background
While assisted living (AL) and nursing home (NHs) residents in share vulnerabilities, AL provides fewer staffing resources and services. Research has largely neglected AL, especially during the COVID-19 pandemic. Our study compared trends of practice-sensitive, risk-adjusted quality indicators between AL and NHs, and changes in these trends after the start of the pandemic.Methods
This repeated cross-sectional study used population-based resident data in Alberta, Canada. Using Resident Assessment Instrument data (01/2017–12/2021), we created quarterly cohorts, using each resident's latest assessment in each quarter. We applied validated inclusion/exclusion criteria and risk-adjustments to create nine quality indicators and their 95% confidence intervals (CIs): potentially inappropriate antipsychotic use, pain, depressive symptoms, total dependency in late-loss activities of daily living, physical restraint use, pressure ulcers, delirium, weight loss, urinary tract infections. Run charts compared quality indicators between AL and NHs over time and segmented regressions assessed whether these trends changed after the start of the pandemic.Results
Quarterly samples included 2015–2710 AL residents and 12,881–13,807 NH residents. Antipsychotic use (21%–26%), pain (20%–24%), and depressive symptoms (17%–25%) were most common in AL. In NHs, they were physical dependency (33%–36%), depressive symptoms (26%–32%), and antipsychotic use (17%–22%). Antipsychotic use and pain were consistently higher in AL. Depressive symptoms, physical dependency, physical restraint use, delirium, weight loss were consistently lower in AL. The most notable segmented regression findings were an increase in antipsychotic use during the pandemic in both settings (AL: change in slope = 0.6% [95% CI: 0.1%–1.0%], p = 0.0140; NHs: change in slope = 0.4% [95% CI: 0.3%–0.5%], p < 0.0001), and an increase in physical dependency in AL only (change in slope = 0.5% [95% CI: 0.1%–0.8%], p = 0.0222).Conclusions
QIs differed significantly between AL and NHs before and during the pandemic. Any changes implemented to address deficiencies in either setting need to account for these differences and require monitoring to assess their impact. 相似文献348.
Yuting Song PhD Sascha Bolt PhD Trina Thorne MN Peter Norton MD Jeff Poss PhD Fangfang Fu MS Janet Squires PhD Greta Cummings PhD Carole A. Estabrooks PhD 《Journal of the American Geriatrics Society》2023,71(11):3413-3423