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31.
  • DNA is the sequence that codes for proteins.
  • Messenger RNA is transcribed from the DNA sequence of genes and translated into protein.
  • It can be difficult to predict how a change in the DNA sequence will affect messenger RNA and protein quantity and quality.
  • DNA translocation changes can cause the joining of sequences from two different genes or different parts of the same gene.
  • DNA sequencing is often used clinically to predict how DNA changes might affect proteins.
  • Alternatively, RNA sequencing can be used as a more direct measure of the effect of DNA changes on the protein products.
  • This sequencing is important for identifying changes in cancer that may indicate response to targeted therapy, prognosis, or diagnosis.
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总结1例外阴Paget’s病术后创面感染的护理体会,利用伤口评估三角工具对患者创面进行评估,通过使用液体伤口敷料联合银离子敷料控制感染,富血小板血浆技术促进伤口愈合,个体化健康教育提高患者治疗依从性的整体干预方案对伤口进行有效管理,结果显示伤口愈合效果良好。  相似文献   
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《Radiography》2022,28(2):454-459
IntroductionMR facilities must implement and maintain adequate screening and safety procedures to ensure safety during MR examinations. The aim of this study was to evaluate a multi-step MR safety screening process used at a 7T facility regarding incidence of different types of safety risks detected during the safety procedure.MethodsSubjects scheduled for an MR examination and having entered the 7T facility during 2016–2019 underwent a pre-defined multi-step MR safety screening process. Screening documentation of 1819 included subjects was reviewed, and risks identified during the different screening steps were compiled. These data were also related to documented decisions made by a 7T MR safety committee and reported MR safety incidents.ResultsPassive or active implants (n = 315) were identified in a screening form and/or an additional documented interview in 305 subjects. Additional information not previously self-reported by the subject, regarding implants necessitating safety decisions performed by the staff was revealed in the documented interview in 102 subjects (106 items). In total, the 7T MR safety committee documented a decision in 36 (2%) of the included subjects. All of these subjects were finally cleared for scanning.ConclusionA multi-step screening process allows a thorough MR screening of subjects, avoiding safety incidents. Different steps in the process allow awareness to rise and items to be detected that were missed in earlier steps.Implications for practiceSafety questions posed at a single timepoint during an MR screening process might not reveal all safety risks. Repetition and rephrasing of screening questions leads to increased detection of safety risks. This could be effectively mitigated by a multi-step screening process. A multi-disciplinary safety committee is efficient at short notice responding to unexpected safety issues.  相似文献   
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A male in his late 50s had been complaining of headaches and dizziness for 25 years. He also had episodes of losing consciousness, but had not sought treatment because of financial hardship. He was found in the ocean. Autopsy revealed foamy liquid leaking from his nose and mouth, and pleural effusions. The trachea and bronchi contained the same foamy liquid. The lungs were swollen and edematous, and leaked a large amount of foamy liquid. His cause of death was diagnosed as drowning. In the brain, the veins on the frontal lobe and the temporal pole, each on the right cerebral hemisphere, were dilated. A vascular lesion measuring 5 × 5 × 8 cm was found on the bottom of the right frontal lobe, and was located between the right middle cerebral artery and those veins. This vascular lesion extended to the brain parenchyma, and the basal ganglia of the right cerebrum was displaced outward and upward. The vascular lesions in the brain showed blood vessels of various sizes and shapes, and some of the vessel walls were thickened. The vascular lesion on the right frontal lobe was diagnosed as an arteriovenous malformation (AVM). According to the police investigation, the harbor where his body was found was a place he often came for fishing and walking. The possibility of suicide cannot be ruled out. Moreover, it was considered that his AVM might have rendered him unconscious, causing him to fall into the ocean.  相似文献   
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BackgroundGlioma accounts for most central nervous system tumors, and the degree of invasion and malignancy are higher in the recurrent glioma. Photodynamic therapy (PDT) is an effective strategy in glioma. This study aimed to explore the risk factors for re-recurrence after a second glioma surgery and the effects of PDT on re-recurrence.MethodsThis was a retrospective study in the Second Affiliated Hospital of Harbin Medical University in China, and 43 patients that received the secondary surgery for recurrent glioma were included. The Kaplan-Meier test and Cox proportional hazard method were used to analyze.ResultsThe total re-recurrence rate after the second surgery for recurrent glioma was 48.84%. When the age increased by 1, the risk of re-recurrence increased 1.065 times (95% CI 1.000–1.134, P = 0.049). High matrix metalloproteinase (MMP) 2 expression was associated with a significantly higher risk of re-recurrence than low MMP2 expression (HR = 25.550, 95% CI 3.190–204.650, P = 0.002). Pathological grades IV and III were associated with a significantly higher risk of re-recurrence than pathological grade II (HR = 17.121, 95% CI 2.345–124.986, P = 0.005; HR = 2863.470, 95% CI 100.697–81,427.197, P < 0.001). PDT decreased the risk of re-recurrence (HR = 25.550, 95% CI 3.190–204.650, P = 0.002) and increased survival time (HR = 3.611, 95% CI 1.012–12.888, P = 0.048).ConclusionThe age, MMP2 expression, and pathological grade are independent risk factors for re-recurrence after a second surgery for recurrent glioma. PDT during the second surgery decreased the risk of re-recurrence and increased survival time.  相似文献   
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A magnetic resonance imaging (MRI) sequence independent deep learning technique was developed and validated to generate synthetic computed tomography (sCT) scans for MR guided proton therapy. 47 meningioma patients previously undergoing proton therapy based on pencil beam scanning were divided into training (33), validation (6), and test (8) cohorts. T1, T2, and contrast enhanced T1 (T1CM) MRI sequences were used in combination with the planning CT (pCT) data to train a 3D U-Net architecture with ResNet-Blocks. A hyperparameter search was performed including two loss functions, two group sizes of normalisation, and depth of the network. Training outcome was compared between models trained for each individual MRI sequence and for all sequences combined. The performance was evaluated based on a metric and dosimetric analysis as well as spot difference maps. Furthermore, the influence of immobilisation masks that are not visible on MRIs was investigated. Based on the hyperparameter search, the final model was trained with fixed features per group for the group normalisation, six down-convolution steps, an input size of 128 × 192 × 192, and feature loss. For the test dataset for body/bone the mean absolute error (MAE) values were on average 79.8/216.3 Houndsfield unit (HU) when trained using T1 images, 71.1/186.1 HU for T2, and 82.9/236.4 HU for T1CM. The structural similarity metric (SSIM) ranged from 0.95 to 0.98 for all sequences. The investigated dose parameters of the target structures agreed within 1% between original proton treatment plans and plans recalculated on sCTs. The spot difference maps had peaks at ±0.2 cm and for 98% of all spots the difference was less than 1 cm. A novel MRI sequence independent sCT generator was developed, which suggests that the training phase of neural networks can be disengaged from specific MRI acquisition protocols. In contrast to previous studies, the patient cohort consisted exclusively of actual proton therapy patients (i.e. “real-world data”).  相似文献   
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