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991.
目的介绍手术动力设备的电磁兼容测试方法,为多功能手术动力设备测试提供指引。方法通过对常见手术动力设备的不同功能逐一测试得出的结果进行比对,分析不同功能在同一检测项目中的差异。结果传导发射(Conduction Emission,CE)与负载引起的功率变化有关,辐射发射(Radiation Ernission,RE)与负载引起的功率变化无必然联系。静电放电(Electrostatic Discharge,ESD)与负载刀头到设备输入插口的插入损耗有关。结论可选择输入功率较大的负载进行CD和RE测试;电路原理不明确时,还可通过频谱仪预测判断后,选择出现最大幅值的负载进行RE测试;ESD测试选择插入损耗最小的负载测试;其余抗扰度项目可选取任一负载测试。 相似文献
992.
《Saudi Dental Journal》2022,34(5):385-389
PurposeThis work aimed to study the rate and quality of maturation of the mineral component of retained teeth 3.8, 4.8 and lower jaw fragment of a human in connective tissue dysplasia in different periods of postpartum ontogenesis.MethodsThe study involved 102 men (76 with connective tissue dysplasia and 26 without connective tissue dysplasia) divided into groups by age: 31–40, 41–50, 51–60 years. One tooth 3.8, 4.8 and a fragment of the alveolar part of the lower jaw in the projection of teeth 3.8, 4.8 0.5*0.5 cm in size were extracted from each examinee for medical indications.ResultsLow optical density values are observed at the age of 41–50 years, at the age of 51–60 years, indicating decreased mineral density and the presence of total areas of hypomineralization from the age 31–40 years in connective tissue dysplasia. At the age of 41–50, 51–60 years, at the boundary of connective tissue structures and periosteum, a pronounced sclerosis and deformation of delineation elements were observed; at the age of 31–40 years, the indicated changes were less pronounced. At the age of 31–40 years, the level of bone plate dissection has a local character, after 40 years, it has a generalized character.ConclusionProgressive osteoporosis of the mandible and incomplete amelogenesis are an obstacle to the correct and harmonious teething of the lower wisdom teeth after the age of 30. 相似文献
993.
《Nutrition, metabolism, and cardiovascular diseases : NMCD》2022,32(5):1165-1174
Background and aimsThe extent to which dietary patterns influence the risk of abnormal blood lipids throughout young adulthood remains unclear. The aim was to investigate whether early young adulthood dietary patterns predict the risk of abnormal blood lipids during later young adulthood.Methods and resultsWe used data from a long running birth cohort study in Australia. Western dietary pattern rich in meats, processed foods and high-fat dairy products and prudent pattern rich in fruit, vegetables, fish, nuts, whole grains and low-fat dairy products were derived using principal component analysis at the 21-year follow-up from dietary data obtained using a food frequency questionnaire. After 9-years, fasting blood samples of all participants were collected and their total, low-density lipoprotein (LDL) and high-density lipoprotein (HDL) cholesterols and triglyceride (TG) levels were measured. Abnormal blood lipids were based on clinical cut-offs for total, LDL and HDL cholesterols, and TG and relative distributions for total:HDL and TG:HDL cholesterols ratios. Log-binomial models were used to estimate risk of each outcome in relation to dietary patterns. Greater adherence to the Western pattern predicted increased risks of high LDL (RR: 1.47; 95%CI: 1.06, 2.03) and TG (1.90; 1.25, 2.86), and high ratios of total:HDL (1.48; 1.00, 2.19) and TG:HDL (1.78; 1.18, 2.70) cholesterols in fully adjusted models. Conversely, a prudent pattern predicted reduced risks of low HDL (0.58; 0.42, 0.78) and high TG (0.66; 0.47, 0.92) and high total:HDL (0.71; 0.51, 0.98) and TG:HDL (0.61; 0.45, 0.84) cholesterols ratios.ConclusionThis is the first prospective study to show greater adherence to unhealthy Western diet predicted increased risks of abnormal blood lipids, whereas healthy prudent diet predicted lower such risks in young adults. Addressing diets in early course may improve cardiovascular health of young adults. 相似文献
994.
Sho Tamai Masashi Kinoshita Hemragul Sabit Takuya Furuta Katsuyoshi Miyashita Kaori Yoshimura Taku Homma Kenichi Harada Mitsutoshi Nakada 《Neuropathology》2019,39(3):218-223
Glioblastoma (GBM) with primitive neuronal component (GBM‐PNC) is a rare GBM subtype recently categorized by the World Health Organization in the revised classification system of 2016. Extracranial metastases originating from GBM‐PNC are rare and metastasis to solid organs has never been reported. Herein, we present the first case of metastasis of GBM‐PNC to the lung. A 49‐year‐old man presenting with headache was diagnosed with multiple tumors adhering to the dura matter in the right temporal lobe. Despite surgery and chemoradiotherapy, 2 months after the initial therapy, the patient presented with CSF dissemination and lung metastases. The patient succumbed to the disease 12 months after the first surgery. We discuss the possibility that GBM‐PNC may constitute a subtype of glioma with particularly poor prognosis, tending to dissemination and metastasis. Our results suggest that a complementary regular inspection of the whole body via CT may be recommended for the follow‐up of patients with GBM‐ PNC. 相似文献
995.
996.
目的实现基于成像式光电容积描记技术(iPPG)的心率变异性非接触式测量,并探讨极短时分析的可行性。方法使用高速摄像机拍摄12名男性受试者人脸视频,通过感兴趣区域提取,独立成分分析等方法得到与脉搏相关的iPPG信号,并进行了心率变异性的极短时分析。结果与心电信号相比,心率变异性的部分时域和频域特征具有较高的准确性和相关性:NNVGR和RMSSD的相关性最好,均在0.98以上,SDNN相关性在0.9左右;频域特征中,VLF、LF、HF的相关性均在0.8以上,pLF、pHF、LFHFRatio的相关性较低,且个体差异较大。结论iPPG技术可用于心率变异性的准确测量和监测,对于非接触条件下生理信号监测具有重要意义。 相似文献
997.
《European journal of surgical oncology》2020,46(6):1080-1087
IntroductionRecent reports on gene expression profiling (GEP) show several genes associated with malignant progression of GIST. However, genes associated with malignant transformation have not been clarified. Here, we aimed to reveal distinct genes in aggressive malignant GIST, using comprehensive gene expression analysis.Materials and methodsWe investigated GEP obtained by microarrays for 43 gastric GISTs, which mostly harbored KIT and PDGFRA mutations and integrated clinicopathological risk information. RT-PCR and immunohistochemistry were performed for FZD7, a receptor of Wnt ligands.ResultsGEP divided 43 gastric GISTs into two clusters. A cluster included seven of eight high-risk GISTs (88%) in modified NIH classification and was defined as high-risk cluster; the other cluster was defined as low-risk cluster. The number of probes with over 3-fold changes between the two clusters was 1,177, in which probes corresponding to 16 oncogenes were included. Genes involved in the Wnt signaling pathway were the most abundant among the 16 oncogenes. Focusing on 73 Wnt signaling pathway genes of the 21,578 probes, 12 upregulated and 5 downregulated genes were found in the high-risk cluster. Major cascade genes promoting the Wnt/β-catenin signaling pathway, including WNT11, FZD family, and DVL2, were upregulated in the high-risk cluster. SNAI1, SNAI2, and BIRC5, which are activated by this pathway and increase cell proliferation, were also upregulated. These gene expression alterations were consistent in the positive direction of this pathway. GISTs in high-risk cluster strongly expressed FZD7.ConclusionWnt/β-catenin signaling pathway may play an important role in malignant transformation of indolent GIST. 相似文献
998.
999.
目的 建立指纹图谱和多指标定量与化学计量学相结合的湿热痹片质量评价方法。方法 采用Waters Symmetry C18色谱柱(250 mm×4.6 mm,5 μm),柱温30℃;检测波长分别为303 nm(检测桑皮苷A、桑皮苷F、桑辛素M)和270 nm(检测连翘酯苷B、连翘酯苷A、连翘苷、苍术素醇、白术内酯II、苍术素);流动相为乙腈-0.2%磷酸水溶液,梯度洗脱,体积流量1.0 mL/min。利用中药色谱指纹图谱相似度评价系统(2012.130723版)建立湿热痹片的HPLC指纹图谱,确定共有峰并进行相似度评价;并对桑皮苷A、桑皮苷F、桑辛素M、连翘酯苷B、连翘酯苷A、连翘苷、苍术素醇、白术内酯II、苍术素的含量测定方法进行方法学验证;基于指纹图谱共有峰峰面积测定结果,采用聚类分析和主成分分析等化学计量学方法对不同批次的湿热痹片进行质量评价。结果 湿热痹片HPLC指纹图谱确认了16个共有峰,指认9个共有峰,10批湿热痹片样品相似度均大于0.95,相似度良好;9种成分在各自的质量浓度范围内线性关系良好(r2 ≥ 0.999 1),平均加样回收率分别为98.87%、97.44%、97.94%、98.39%、100.13%、99.06%、96.80%、98.44%、99.15%,RSD分别为1.42%、1.17%、1.30%、0.91%、0.86%、1.23%、1.08%、1.37%、0.79%;10批次样品中桑皮苷A、桑皮苷F、桑辛素M、连翘酯苷B、连翘酯苷A、连翘苷、苍术素醇、白术内酯II、苍术素的质量浓度分别在0.192~0.289、0.057~0.095、0.113~0.158、0.309~0.375、1.537~1.916、0.478~0.596、0.049~0.072、0.279~0.354、0.629~0.759 mg/g。10批湿热痹片聚为2类;主成分1~6是影响湿热痹片质量评价的主要因子。结论 所建立的方法操作便捷、结果准确、重复性好,可用于湿热痹片的质量控制和评价。 相似文献
1000.
Colorectal adenocarcinoma with mucinous component: relation of MMP‐13, EGFR,and E‐cadherin expressions to clinicopathological features and prognosis
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Abd Al‐Rahman Mohammad Foda Amira Kamal El‐Hawary Azza Abdel Aziz 《APMIS : acta pathologica, microbiologica, et immunologica Scandinavica》2015,123(6):502-508
The aim of this study was to compare colorectal adenocarcinoma with mucinous component, ordinary adenocarcinoma (OA) and mucinous adenocarcinoma (MA) regarding clinicopathological parameters, survival, EGFR, MMP‐13, and E‐cadherin. We studied tumor tissue specimens from 28 patients with adenocarcinoma with mucinous component, 47 with OA, and 56 with MA, who underwent radical surgery from January 2007 to January 2012 at the Gastroenterology Centre, Mansoura University, Egypt. High density manual tissue microarrays were constructed and immunohistochemistry for EGFR, MMP‐13, and E‐cadherin was done. Colorectal adenocarcinoma with mucinous component (AWMC) was significantly associated with more perineural invasion, lower EGFR, and MMP‐13 expressions than OA, with no difference in E‐cadherin expression. Conversely, only microscopic abscess formation was significantly more with colorectal AWMC than MC with no difference in EGFR, MMP‐13 and E‐cadherin expression between both groups. Colorectal AWMC showed a better survival than MA with no difference with OA. In a univariate analysis, EGFR, MMP‐13, and E‐cadherin expressions did not show a significant impact on disease‐free or overall survival in patients with colorectal AWMC. Colorectal AWMC remains a vague entity that resembles OA in some clinicopathological and molecular respects as well as MA. 相似文献