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排序方式: 共有8160条查询结果,搜索用时 15 毫秒
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Efrem S. Lim Natalie M. Meinerz Blake Primi David Wang Robert L. Garcea 《Emerging infectious diseases》2014,20(9):1559-1561
STL polyomavirus (STLPyV) was recently identified in human specimens. To determine seropositivity for STLPyV, we developed an ELISA and screened patient samples from 2 US cities (Denver, Colorado [500]; St. Louis, Missouri [419]). Overall seropositivity was 68%–70%. The age-stratified data suggest that STLPyV infection is widespread and commonly acquired during childhood. 相似文献
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Mauro Loi Michael Frelinghuysen Natalie Desiree Klass Esther Oomen-De Hoop Patrick Vincent Granton Joachim Aerts Cornelis Verhoef Joost Nuyttens 《Clinical & experimental metastasis》2018,35(7):625-633
Stereotactic body radiotherapy (SBRT) has emerged as an effective option in oligo-metastatic cancer patients affected by lymph node metastases, but its use might be questioned due to risk of regional and distant dissemination through the lymph node chain. The primary aim of our study was to assess the loco-regional control following SBRT in this setting. Ninety-one patients undergoing SBRT for at least one lymph node metastasis from miscellaneous primary tumors were retrospectively evaluated for patterns of failure and toxicity. locoregional relapse-free survival (LRRFS) and distant metastasis-free survival (DMFS) at 4 years were 79 and 44%. Repeated use of local therapy after progression resulted in a median interval of 17 months until allocation to systemic therapy or supportive care. Forty-three percent of patients were alive at 4 years. Local failure, occurring in 15% of patients, was the only predictor of poor survival (HR: 3.06). Tumor diameter?≥?30 mm and urothelial primary tumor predicted for impaired local control (HR: 4.59 and 5.43, respectively). Metastases from pulmonary cancer showed a significant earlier distant dissemination (HR: 3.53). Only acute and late grade 1–2 toxicities were reported except for 1 case of G3 dysphagia. Loco-regional failure risk is low (18%) and justifies the use of local therapies for patients with oligometastatic disease. Durable disease remission can be achieved by iterative use of local approaches. Local control is correlated to improved OS. Diameter and primary tumor type may affect response to SBRT and risk for early metastatic dissemination. 相似文献
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ABSTRACT: BACKGROUND: The objective of this study was to conduct a systematic review with meta-analysis of studies assessing the association between living in an urban environment and the development of the Crohn's disease (CD) or ulcerative colitis (UC). METHODS: A systematic literature search of MEDLINE (1950-Oct. 2009) and EMBASE (1980-Oct. 2009) was conducted to identify studies investigating the relationship between urban environment and IBD. Cohort and case-control studies were analyzed using incidence rate ratio (IRR) or odds ratio (OR) with 95 % confidence intervals (CIs), respectively. Stratified and sensitivity analyses were performed to explore heterogeneity between studies and assess effects of study quality. RESULTS: The search strategy retrieved 6940 unique citations and 40 studies were selected for inclusion. Of these, 25 investigated the relationship between urban environment and UC and 30 investigated this relationship with CD. Included in our analysis were 7 case-control UC studies, 9 case-control CD studies, 18 cohort UC studies and 21 cohort CD studies. Based on a random effects model, the pooled IRRs for urban compared to rural environment for UC and CD studies were 1.17 (1.03, 1.32) and 1.42 (1.26, 1.60), respectively. These associations persisted across multiple stratified and sensitivity analyses exploring clinical and study quality factors. Heterogeneity was observed in the cohort studies for both UC and CD, whereas statistically significant heterogeneity was not observed for the case-control studies. CONCLUSIONS: A positive association between urban environment and both CD and UC was found. Heterogeneity may be explained by differences in study design and quality factors. 相似文献
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Applying terrestrial lidar for evaluation and calibration of airborne lidar-derived shrub biomass estimates in Arctic tundra 总被引:1,自引:0,他引:1
Heather E. Greaves Lee A. Vierling Jan U. H. Eitel Natalie T. Boelman Troy S. Magney Case M. Prager 《Remote sensing letters.》2017,8(2):175-184
Monitoring of climate-driven expansion of low-stature shrubs in Arctic tundra can be improved through application of high-resolution remote sensing. However, the destructive nature of harvest sampling that is usually performed for validation of these data is resource intensive and can limit future comparisons by destroying benchmark measurements. We compared aboveground shrub biomass estimates derived from terrestrial laser scanning (TLS) and airborne laser scanning (ALS) with the goal of determining whether TLS data can be used to accurately calibrate ALS estimates of shrub biomass in Arctic tundra. We used a leave-one-out cross-validation calibration of canopy volume against harvested shrub biomass to establish predictive relationships between TLS canopy volume and harvested shrub biomass, and between ALS canopy volume and TLS-derived shrub biomass estimates. TLS produced more accurate predictions of shrub biomass (R2 = 0.78; root mean square deviation [RMSD] = 102 g) than did ALS, but the accuracy of ALS-derived shrub biomass predictions was the same whether they were calibrated directly against harvest biomass or against TLS-derived estimates of biomass (R2 = 0.62; RMSD = 140 g). Our results suggest that once the initial TLS-harvest relationship is known, TLS can provide valid ground reference data for calibration of ALS-derived estimates of shrub biomass without the need for additional destructive harvest. 相似文献
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