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21.
Hemangioblastoma (HB) is uncommon, with only a few cases of hemangioblastoma with von Hippel-Lindau disease (VHL) located in cauda equina previously reported. We describe a case of hemangioblastoma misdiagnosed as nerve sheath tumour in the cauda equina. 相似文献
22.
扶正食疗方对化疗致骨髓抑制大鼠外周血细胞的影响 总被引:2,自引:0,他引:2
目的 观察扶正食疗方不同干预方法对化疗所致骨髓抑制模型大鼠外周血细胞的影响.方法 将112只SD大鼠随机分为空白组、模型组、低剂量食疗方预防组(低预防组)、高剂量食疗方预防组(高预防组)、低剂量食疗方治疗组(低治疗组)、高剂量食疗方治疗组(高治疗组)、高剂量当归补血汤拆方组(高拆1组)和高剂量猪蹄汤拆方组(高拆2组)8组.均以环磷酰胺腹腔注射建立骨髓抑制大鼠模型.空白组、模型组造模后均灌胃生理盐水;低预防组、高预防组均于造模前1周即开始灌胃低、高剂量归芪补血猪蹄汤;低治疗组、高治疗组均于造模后灌胃低、高剂量归芪补血猪蹄汤;高拆1组、高拆2组造模后分别灌高剂量当归补血汤和高剂量猪蹄汤.8组均灌胃至造模后14d结束.结果 造模后5d、15d,模型组、低预防组、高预防组、低治疗组、高治疗组、高拆1组和高拆2组与空白组体质量比较,差异有统计学意义(均P<0.05);造模后5d除低预防组外,对照组、高预防组与高、低治疗组白细胞显著高于模型组(均P<0.05).结论 归芪补血猪蹄汤预防和治疗性干预可提高骨髓抑制模型大鼠外周白细胞计数. 相似文献
23.
Jiang Bian Tianchen Lyu Alexander Loiacono Tonatiuh Mendoza Viramontes Gloria Lipori Yi Guo Yonghui Wu Mattia Prosperi Thomas J George Jr Christopher A Harle Elizabeth A Shenkman William Hogan 《J Am Med Inform Assoc》2020,27(12):1999
ObjectiveTo synthesize data quality (DQ) dimensions and assessment methods of real-world data, especially electronic health records, through a systematic scoping review and to assess the practice of DQ assessment in the national Patient-centered Clinical Research Network (PCORnet).Materials and MethodsWe started with 3 widely cited DQ literature—2 reviews from Chan et al (2010) and Weiskopf et al (2013a) and 1 DQ framework from Kahn et al (2016)—and expanded our review systematically to cover relevant articles published up to February 2020. We extracted DQ dimensions and assessment methods from these studies, mapped their relationships, and organized a synthesized summarization of existing DQ dimensions and assessment methods. We reviewed the data checks employed by the PCORnet and mapped them to the synthesized DQ dimensions and methods.ResultsWe analyzed a total of 3 reviews, 20 DQ frameworks, and 226 DQ studies and extracted 14 DQ dimensions and 10 assessment methods. We found that completeness, concordance, and correctness/accuracy were commonly assessed. Element presence, validity check, and conformance were commonly used DQ assessment methods and were the main focuses of the PCORnet data checks.DiscussionDefinitions of DQ dimensions and methods were not consistent in the literature, and the DQ assessment practice was not evenly distributed (eg, usability and ease-of-use were rarely discussed). Challenges in DQ assessments, given the complex and heterogeneous nature of real-world data, exist.ConclusionThe practice of DQ assessment is still limited in scope. Future work is warranted to generate understandable, executable, and reusable DQ measures. 相似文献
24.
Hong Xia MA Ruo Lin WANG Yi Fei NIE Jia SU Dong Xiao LI Yi LI Yan Hua DU Hai Yan WEI Xing Le LI Zhe WANG Bian Li XU Xue Yong HUANG 《Biomedical and environmental sciences : BES》2019,32(11):797-803
ObjectiveTo survey avian influenza A viruses (AIVs) in the environment and explore the reasons for the surge in human H7N9 cases.MethodsA total of 1,045 samples were collected from routine surveillance on poultry-related environments and 307 samples from human H7N9 cases-exposed environments in Henan from 2016 to 2017. The nucleic acids of influenza A (Flu A), H5, H7, and H9 subtypes were detected by real-time polymerase chain reaction.ResultsA total of 27 H7N9 cases were confirmed in Henan from 2016 to 2017, 24 had a history of live poultry exposure, and 15 had H7N9 virus detected in the related live poultry markets (LPMs). About 96% (264/275) Flu A positive-environmental samples were from LPMs. H9 was the main AIV subtype (10.05%) from routine surveillance sites with only 1 H7-positive sample, whereas 21.17% samples were H7-positive in H7N9 cases-exposed environments. Samples from H7N9 cases-exposed LPMs (47.56%) had much higher AIVs positive rates than those from routine surveillance sites (12.34%). The H7+H9 combination of mixed infection was 78.18% (43/55) of H7-positive samples and 41.34% (43/104) of H9-positive samples.ConclusionThe contamination status of AIVs in poultry-related environments is closely associated with the incidence of human infection caused by AIVs. Therefore, systematic surveillance of AIVs in LPMs in China is essential for the detection of novel reassortant viruses and their potential for interspecies transmission. 相似文献
25.
目的探讨以团队为基础的教学(team-based learning,TBL)联合以案例为基础的教学(case-based learning,CBL)在军人积极心理学教学中的应用效果。方法选取陆军军医大学校2017级临床医学专业100名本科生作为教学对象,随机分为TBL联合CBL教学组(n=50)和传统教学组(n=50)。通过基础理论知识及案例分析考核、问卷调查和心理测评等方式评估两种教学方法的教学效果。运用SPSS 19.0对结果进行t检验。结果TBL联合CBL教学组在理论知识得分(54.87±4.98)高于传统教学组(48.65±3.51);案例分析考核得分(36.84±2.73)也高于传统教学组(32.37±2.34);在心理测评结果中,TBL联合CBL教学组在SCL-90后测得分(143.31±43.62)低于传统教学组(149.89±46.96);ERC、GWB后测得分(48.76±5.37)、(107.87±15.56)均高于传统教学组(43.58±5.79)、(102.32±12.13)。此外,TBL联合CBL教学组学生对该教学满意率达95.83%(46/50)。结论TBL联合CBL教学在军人积极心理学教学中能取得良好的教学效果,提高学员的知识应用水平和心理调适能力,具有较好的可行性和适用性。 相似文献
26.
Wei Bian Christopher P. Hess Susan M. Chang Sarah J. Nelson Janine M. Lupo 《Neuroradiology》2014,56(2):91-96
Introduction
Cerebral microbleeds have been observed in normal-appearing brain tissue of patients with glioma years after receiving radiation therapy. The contrast of these paramagnetic lesions varies with field strength due to differences in the effects of susceptibility. The purpose of this study was to compare 3T and 7T MRI as platforms for detecting cerebral microbleeds in patients treated with radiotherapy using susceptibility-weighted imaging (SWI).Methods
SWI was performed with both 3T and 7T MR scanners on ten patients with glioma who had received prior radiotherapy. Imaging sequences were optimized to obtain data within a clinically acceptable scan time. Both T2*-weighted magnitude images and SWI data were reconstructed, minimum intensity projection was implemented, and microbleeds were manually identified. The number of microbleeds was counted and compared among datasets.Results
Significantly more microbleeds were identified on SWI than magnitude images at both 7T (p?=?0.002) and 3T (p?=?0.023). Seven-tesla SWI detected significantly more microbleeds than 3T SWI for seven out of ten patients who had tumors located remote from deep brain regions (p?=?0.016), but when the additional three patients with more inferior tumors were included, the difference was not significant.Conclusion
SWI is more sensitive for detecting microbleeds than magnitude images at both 3T and 7T. For areas without heightened susceptibility artifacts, 7T SWI is more sensitive to detecting radiation therapy-induced microbleeds than 3T SWI. Tumor location should be considered in conjunction with field strength when selecting the most appropriate strategy for imaging microbleeds. 相似文献27.
Digital Breast Tomosynthesis: A New Diagnostic Method for Mass‐Like Lesions in Dense Breasts 下载免费PDF全文
Tiantian Bian MS Qing Lin PhD Chunxiao Cui MS Lili Li MS Chunhua Qi MS Jie Fei MS Xiaohui Su MS 《The breast journal》2016,22(5):535-540
To compare the rates and accuracy of digital breast tomosynthesis (DBT) and 2D digital mammography (DM) for detecting and diagnosing mass‐like lesions in dense breasts. Mediolateral and craniocaudal images taken with DBT (affected breast) and DM (both breasts) of the dense breasts of 631 women were assessed independently using Breast Imaging Reporting and Data System (BI‐RADS) scores. Images were compared for detection and diagnostic accuracy for masses; sensitivity and specificity of diagnosis; false‐negative and recall rates; and clarity of display, particularly of margins and spicules. Histopathology was conducted via surgical biopsies of all patients. The detection and diagnostic accuracy rates of DBT images (84.3% and 82.3%, respectively) were significantly higher than that of DM (77.3% and 73.4%; p < 0.01, both). The sensitivity and specificity of DBT (68.1% and 95.2%) were higher than that of DM (58.8% and 86.7%), whereas the recall rate of DBT was lower (3.6% cf. 9.8%). The number of cases of benign circumscribed masses and malignant spiculated masses detected by DBT (172 and 182) was significantly higher than the number detected through DM (75 and 115; p < 0.01, both). Radiologists assigned higher BI‐RADS scores for probability of malignancy to DBT images than DM, to lesions proved malignant (p = 0.025); for benign cases, the methods were comparable (p = 0.065). Compared with DM, DBT yielded significantly higher rates of detection and diagnostic accuracy for benign and malignant masses, with greater sensitivity and specificity and lower recall rates. In addition, DBT images facilitated analysis of margins, and the rate of accuracy for judgments of malignancy probability was higher, as proved on biopsy. 相似文献
28.
Harry K.W. Kim Haikuo Bian James Aya-ay Amanda Garces Elise F. Morgan Shawn R. Gilbert 《BONE》2009,44(2):280-288
HIF-1α has been shown to be a central mediator of cellular response to hypoxia. The role it plays after ischemic injury to the immature femoral head is unknown. The purpose of this study was to determine the region of the femoral head affected by hypoxia following ischemic injury to the immature femoral head and to determine the site of HIF-1α activation and revascularization. We hypothesize that the epiphyseal cartilage, rather than the bony epiphysis, is the site of HIF-1α activation following ischemic osteonecrosis and that the epiphyseal cartilage plays an important role in the revascularization process.Materials and methodsFemoral head osteonecrosis was surgically induced in 56 immature pigs. Hypoxyprobe staining, cell viability assay, HIF-1α western blot, RT-qPCR of HIF-1α, VEGF, VEGFR2, and PECAM, and micro-CT assessments of microfil-infused femoral heads were performed.ResultsSevere hypoxia was present in the bony epiphysis and the lower part of the epiphyseal cartilage following ischemia. In the bony epiphysis, extensive cell death and tissue necrosis was observed with degradation of proteins and RNAs which precluded further analysis. In the epiphyseal cartilage, the loss of cell viability was limited to its deep layer with the remainder of the cartilage remaining viable. Furthermore, the cartilage from the ischemic side showed a significant increase in HIF-1α protein level and HIF-1α expression. VEGF expression in the cartilage was dramatically and significantly increased at 24 h, 2 and 4 weeks (p < 0.05 for all) with 5 to 10 fold increase being observed on the ischemic side compared to the normal side. PECAM and VEGFR2 expressions in the cartilage were both significantly decreased at 24 h but returned to the normal levels by 2 and 4 weeks, respectively. Micro-CT showed revascularization of the cartilage on the ischemic side with the vessel volume/total volume equaling the normal side by 4 weeks.ConclusionsAcute ischemic injury to the immature femoral head induced severe hypoxia and cell death in the bony epiphysis and the deep layer of the epiphyseal cartilage. Viable chondrocytes in the superficial layer of the epiphyseal cartilage showed HIF-1α activation and VEGF upregulation with subsequent revascularization occurring in the cartilage. 相似文献
29.
目的 探讨决策辅助方案在原发性开角型青光眼患者中的应用效果。方法 将100例原发性开角型青光眼患者按住院时间分为对照组与观察组各50例;对照组行常规护理,观察组在常规护理基础上实施决策辅助方案。分别于干预后(出院前)、出院后1、3个月评价干预效果。结果 干预后观察组决策困境得分显著低于对照组,决策准备得分显著高于对照组,出院后1、3个月药物依从性得分显著高于对照组,出院后3个月目标眼压达标率显著高于对照组(均P<0.05)。结论 决策辅助方案的应用可有效降低原发性开角型青光眼患者决策困境水平,提高决策准备度,增强用药依从性,从而提高目标眼压达标率。 相似文献
30.