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991.
Barbara Nasiowska Zdzisaw Bogdanowicz Pawe Bogusz Aneta Bombalska Zygmunt Mierczyk 《Materials》2022,15(1)
This paper presents the effect of deposited graphene oxide coating on fatigue life of austenitic steel 1.4541 at 20 °C, 100 °C, and 200 °C. The study showed a decrease in the fatigue life of samples with a deposited graphene oxide layer in comparison with reference samples at 20 °C and 100 °C. However, an increase in fatigue life of samples with a deposited graphene oxide layer in comparison with reference samples occurred at 200 °C. This relationship was observed for the nominal stress amplitude of 370 and 420 MPa. Measurements of temperature during the tensile failure of the sample and microfractographic analysis of fatigue fractures were performed. Tests have shown that graphene oxide deposited on the steel surface provides an insulating layer. A higher temperature of the samples with a deposited graphene oxide layer was observed during fracture compared to the reference samples. 相似文献
992.
广西藤茶中黄酮类成份的提取工艺研究 总被引:18,自引:0,他引:18
目的:提取分离藤(Ampelosis grossdentata)中的双氢杨梅树皮素(dihydromyricetin)和杨梅素(Myricetin)。方法:采用新的水提取和溶剂分离的方法,经化学和光谱鉴定确定结构。结果:提取产物经确证为双氢杨梅树皮素(dihydromyricetin)和杨梅素(Myricetin),平均收率分别为19.6%和0.51%。结论:该提取法经济、简便,易于操作并且提取率 相似文献
993.
Introduction: The emergence of severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) has evolved into a worldwide outbreak, with significant molecular evolution over time. Large-scale phylodynamic studies allow to map the virus spread and inform preventive strategies. Aim: This study investigates the extent of binational dispersal and dynamics of SARS-CoV-2 lineages between seven border provinces of the adjacent countries of Poland and Germany to reconstruct SARS-CoV-2 transmission networks. Methods: Following three pandemic waves from March 2020 to the end of May 2021, we analysed a dataset of 19,994 sequences divided into B.1.1.7|Alpha and non-Alpha lineage groups. We performed phylogeographic analyses using the discrete diffusion models to identify the pathways of virus spread. Results: Based on population dynamics inferences, in total, 673 lineage introductions (95% HPD interval 641–712) for non-Alpha and 618 (95% HPD interval 599–639) for B.1.1.7|Alpha were identified in the area. For non-Alpha lineages, 5.05% binational, 86.63% exclusively German, and 8.32% Polish clusters were found, with a higher frequency of international clustering observed for B.1.1.7|Alpha (13.11% for binational, 68.44% German and 18.45% Polish, p < 0.001). We identified key transmission hubs for the analysed lineages, namely Saxony, West Pomerania and Lower Silesia. Conclusions: Clustering patterns between Poland and Germany reflect the viral variant transmission dynamics at the international level in the borderline area. Tracing the spread of the virus between two adjacent large European countries may provide a basis for future intervention policies in cross-border cooperation efforts against the spread of the pandemics. 相似文献
994.
Objective To illustrate the use of percutaneous ultrasound-guided biopsy of the gastrointestinal tract in HIV-infected patients to obtain a tissue diagnosis.
Design The technique was used in relation to relevant clinical situations in which a diagnosis may have only been reached by open biopsy.
Method Three HIV-infected patients with suspected gastrointestinal tract lesions underwent percutaneous ultrasound-guided biopsy under local anaesthetic.
Results A tissue diagnosis was made in each case resulting in initiation or continuation of appropriate therapy and avoided the need for open biopsy under general anaesthetic.
Conclusion Although the number of patients undergoing the procedure in this series was small, the technique has so far been shown to be safe and effective with few complications. 相似文献
Design The technique was used in relation to relevant clinical situations in which a diagnosis may have only been reached by open biopsy.
Method Three HIV-infected patients with suspected gastrointestinal tract lesions underwent percutaneous ultrasound-guided biopsy under local anaesthetic.
Results A tissue diagnosis was made in each case resulting in initiation or continuation of appropriate therapy and avoided the need for open biopsy under general anaesthetic.
Conclusion Although the number of patients undergoing the procedure in this series was small, the technique has so far been shown to be safe and effective with few complications. 相似文献
995.
996.
Mirjam EJ van Beelen Tinneke MJ Beirens Mirjam K Struijk Paul den Hertog Anke Oenema Eduard F van Beeck Hein Raat 《BMC public health》2010,10(1):466
Background
Injuries in or around the home are the most important cause of death among children aged 0-4 years old. It is also a major source of morbidity and loss of quality of life. In order to reduce the number of injuries, the Consumer Safety Institute introduced the use of Safety Information Leaflets in the Netherlands to provide safety education to parents of children aged 0-4 years. Despite current safety education, necessary safety behaviours are still not taken by a large number of parents, causing unnecessary risk of injury among young children. In an earlier study an E-health module with internet-based, tailored safety information was developed and applied. It concerns an advice for parents on safety behaviours in their homes regarding their child. The aim of this study is to evaluate the effect of this safety information combined with personal counselling on parents' child safety behaviours. 相似文献997.
998.
Cornelia Knaak Ilse MJ Kant Florian Lammers-Lietz Claudia Spies Theo D Witkamp Georg Winterer Gunnar Lachmann Jeroen de Bresser 《International journal of medical sciences》2021,18(6):1332
BACKGROUND AND PURPOSE: Hyperglycemia can lead to an increased rate of apoptosis of microglial cells and to damaged neurons. The relation between hyperglycemia and cerebrovascular markers on MRI is unknown. Our aim was to study the association between intraoperative hyperglycemia and cerebrovascular markers.METHODS: In this further analysis of a subgroup investigation of the BIOCOG study, 65 older non-demented patients (median 72 years) were studied who underwent elective surgery of ≥ 60 minutes. Intraoperative blood glucose maximum was determined retrospectively in each patient. In these patients, preoperatively and at 3 months follow-up a MRI scan was performed and white matter hyperintensity (WMH) volume and shape, infarcts, and perfusion parameters were determined. Multivariable logistic regression analyses were performed to determine associations between preoperative cerebrovascular markers and occurrence of intraoperative hyperglycemia. Linear regression analyses were performed to assess the relation between intraoperative hyperglycemia and pre- to postoperative changes in WMH volume. Associations between intraoperative hyperglycemia and postoperative WMH volume at 3 months follow-up were also assessed by linear regression analyses.RESULTS: Eighteen patients showed intraoperative hyperglycemia (glucose maximum ≥ 150 mg/dL). A preoperative more smooth shape of periventricular and confluent WMH was related to the occurrence of intraoperative hyperglycemia [convexity: OR 33.318 (95 % CI (1.002 - 1107.950); p = 0.050]. Other preoperative cerebrovascular markers were not related to the occurrence of intraoperative hyperglycemia. Intraoperative hyperglycemia showed no relation with pre- to postoperative changes in WMH volume nor with postoperative WMH volume at 3 months follow-up.CONCLUSIONS: We found that a preoperative more smooth shape of periventricular and confluent WMH was related to the occurrence of intraoperative hyperglycemia. These findings may suggest that a similar underlying mechanism leads to a certain pattern of vascular brain abnormalities and an increased risk of hyperglycemia. 相似文献
999.
MJ Veness 《Journal of Medical Imaging and Radiation Oncology》1999,43(1):76-81
Tongue cancer involving the anterior tongue often presents at an early stage. The aetiology is strongly associated with smoking and alcohol abuse similar to other squamous cell carcinomas (SCC) of the head and neck (HN). Surgery and radiotherapy, either alone or together, offer the prospect of cure in the majority of patients. However, there remains a group of younger patients less than 40 years old for whom outcome is often poor. Presented here is the case of a 24-year-old woman who developed SCC of the anterior tongue. Despite treatment, loco-regional relapse occurred resulting in death. The literature identifies a distinct subgroup of younger patients who develop HN SCC, particularly of the oral cavity. The aetiology remains unclear. Recent studies have looked at the prognostic significance of various new non-clinico-pathological markers in HN SCC (including p53 tumour suppressor gene, cyclin D1 protein, Ki 67 antigen and tumour angiogenesis). The majority of these studies, as expected, have involved the typical HN patient (male, aged > 60 years old). However, the relevance of these studies is of likely importance to all patients diagnosed with HN SCC. The recent use of these non-clinical-pathological markers in HN SCC, including reference to such studies in younger patients, is discussed. The English literature during the past 30 years is reviewed with reference to the diagnosis of tongue SCC in younger patients. 相似文献
1000.
Margot H Uijterwaal Viola MJ Verhoef Peter JF Snijders 《Expert review of molecular diagnostics》2014,14(3):245-248
Several studies have shown that the human papilloma virus (HPV) test is a more sensitive and objective primary cervical cancer screening tool than cytology. Therefore, conversion of cytology into HPV screening (as is planned in The Netherlands and some other European regions) will result in a better protection against cervical cancer and high-grade precursor lesions. Moreover, offering self-sampling for HPV testing will increase screening attendance by re-attracting former non-attendees. However, triage of HPV positive women is necessary because the specificity of HPV testing is 2–4% lower than of cytology. Several triage strategies have been evaluated, of which two, with cytology testing included, are feasible and were recently recommended. As an alternative for cytology triage, objective, non-morphological disease markers are upcoming and so far have shown promising results. Finally, HPV testing can also contribute to a more efficient monitoring of women treated for high-grade cervical precursor lesions, permitting fewer follow-up visits. 相似文献