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1.
Background: Breast cancer (BC) is the most common malignant tumor in women, and its morbidity and mortality are increasing each year, due to the lack of specific clinical symptoms in the early stage of BC, and the lack of diagnostic methods for early breast cancer. Therefore, identifying an effective diagnostic method for early BC has become urgent. Materials and Methods: Breast lesions with a histological diagnosis that were examined by ultrasonic elastography (UE) in our department from June 2020 to December 2021 were reviewed. qRT-PCR was performed to measure the expression levels of miR-144-5p and miR-26b-5p in the plasma of patients with BC. The receiver operating characteristics (ROC) curve and area under the curve (AUC) were used to investigate the potential diagnostic value of miR- 144-5p, miR-26b-5p and the elastographic score in BC. Results: The ultrasonic elastography score(UES) was found to be significantly upregulated in BC compared with that in benign breast lesions, and the AUC, sensitivity and specificity were 0.809, 0.717 and 0.806 for distinguishing BC from benign breast lesions, respectively. miR-144-5p and miR-26b- 5p were found to be upregulated in the plasma of BC patients, and miR-144-5p+miR-26b-5p had 0.781 sensitivity and 0.780 specificity for the diagnosis of BC. Furthermore, we found that the diagnostic performance of miR-144-5p and miR-26b-5p combined with UES for BC had 0.913 sensitivity and 0.890 specificity. Conclusions: The combination of plasma miR-144-5p, miR-26b-5p and UES has a very high clinical application value for the early detection of BC.  相似文献   
2.
Background and aimsWe intended to investigate the predictors for bowel resection in infants with necrotizing enterocolitis (NEC). We further developed a scoring system for better predicting bowel resection.MethodsA total of 207 infants who underwent surgical management at Children's Hospital, Chongqing Medical University between April 2008 and December 2020 were identified for the following investigation. Bowel resection was reviewed among the infants who underwent the procedure. Potential parameters related to bowel resection were explored using a multiple logistic regression method, and then a scoring system was developed.ResultsAmong the 207 patients who underwent operative intervention that were reviewed, 109 infants underwent bowel resection. Multivariate logistic regression analysis showed that birth weight, hypotension, neutropenia, pneumoperitoneum, acidosis, and intestinal wall thickness were predictors related to the occurrence of bowel resection. A 6-point scoring system was further developed based on the obtained total coefficient, and the infants could be divided into low-, moderate- and high-risk groups according to cut values of 7 and 13.ConclusionThe results of this study demonstrated that severe NEC features and low birth weight were associated with bowel resection. The risk scoring system could accurately separate infants that were suspected to have bowel loss during surgery.  相似文献   
3.
In recent years, thermal ablation has played an increasingly important role in treating various tumors in the clinic. A practical thermochromic phantom model can provide a favorable platform for clinical thermotherapy training of young physicians or calibration and optimization of thermal devices without risk to animals or human participants. To date, many tissue-mimicking thermal phantoms have been developed and are well liked, especially the polyacrylamide gel (PAG)–based phantoms. This review summarizes the PAG-based phantoms in the field of thermotherapy, details their advantages and disadvantages and provides a direction for further optimization. The relevant physical parameters (such as electrical, acoustic, and thermal properties) of these phantoms are also presented in this review, which can assist operators in a deeper understanding of these phantoms and selection of the proper recipes for phantom fabrication.  相似文献   
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The interpretation of medical images is a challenging task, often complicated by the presence of artifacts, occlusions, limited contrast and more. Most notable is the case of chest radiography, where there is a high inter-rater variability in the detection and classification of abnormalities. This is largely due to inconclusive evidence in the data or subjective definitions of disease appearance. An additional example is the classification of anatomical views based on 2D Ultrasound images. Often, the anatomical context captured in a frame is not sufficient to recognize the underlying anatomy. Current machine learning solutions for these problems are typically limited to providing probabilistic predictions, relying on the capacity of underlying models to adapt to limited information and the high degree of label noise. In practice, however, this leads to overconfident systems with poor generalization on unseen data. To account for this, we propose a system that learns not only the probabilistic estimate for classification, but also an explicit uncertainty measure which captures the confidence of the system in the predicted output. We argue that this approach is essential to account for the inherent ambiguity characteristic of medical images from different radiologic exams including computed radiography, ultrasonography and magnetic resonance imaging. In our experiments we demonstrate that sample rejection based on the predicted uncertainty can significantly improve the ROC-AUC for various tasks, e.g., by 8% to 0.91 with an expected rejection rate of under 25% for the classification of different abnormalities in chest radiographs. In addition, we show that using uncertainty-driven bootstrapping to filter the training data, one can achieve a significant increase in robustness and accuracy. Finally, we present a multi-reader study showing that the predictive uncertainty is indicative of reader errors.  相似文献   
6.
PurposeTo provide means for calculating the dose received by various tissues of the patient, calculate lung shield, and verify received dose using a phantom as a tool for quality assurance for a planned Total Body Irradiation (TBI) procedure in radiotherapy.MethodUsing Microsoft Visual Basic, MATLAB, and Python, a program for Total Body Irradiation Calculation in Radiotherapy (TBICR) is constructed. It uses patient translation and beam zone method for total body irradiation calculations to compute the proper dose received by the patient and determine the lung shield thickness. There are three main user-friendly interfaces in the application. The first one allows the user to upload the TBI topography and estimate the distances needed for TBI calculations. The second one enables the user to count the number of beam zones needed for each point and estimate the effective area (Aeff) for each level. The third interface estimates the velocity required to deliver the relative dose depending on patient separation, Monitor Units (MU), couch speed and travel distance. It allows the user to compute the required lung shield thickness, read any patient's CT DICOM file and acquire dose in any distinct location using machine learning model to predict the dose.ResultsThe TBICR software has been successfully validated by reproducing all of the manual calculations in an exact and timely manner. TBICR generated more accurate results and confirmed the absorbed dose to patient through measurements on Anderson phantom.ConclusionsA computer program for the calculation of total body irradiation (TBI) is described in full. The dose received at each point on the patient, the calculation of lung shield and the determination of the velocity and time required for the couch movement are all made possible using the software. The ease of use, precision, data storage and printing are some important features of the present software.  相似文献   
7.
Genistein, an isoflavone in soybean products has potential cardio-protective effects and is used also as an alternative for estrogen therapy in postmenopausal women. However, results in this regard are inconsistent and also, not all risk factors related to cardiovascular supportive effects have been meta-analyzed. We searched PubMed, Scopus, ISI Web of Science, and Google Scholar from inception up to October 2020. Random-effects meta-analysis was used for data synthesis. The search included studies with information on genistein supplementation and lipid profile [triglycerides (TG), total cholesterol (TC),low-density lipoprotein (LDL-C), and high-density lipoprotein HDL-C)], systolic and diastolic blood pressure (SBP & DBP), body mass index [BMI] and body weight. Pooled results of studies showed that genistein intake significantly reduced TC [95%CI: -0.49(-0.80, -0.18); P=0.002)], LDL-C [95%CI: -0.60(-1.10, -0.10); P=0.018)] and SBP [95%CI: -0.52(-0.90, -0.14); P=0.007)]. DBP, HLD-C, TG, BMI, and body weight showed no meaningful improvement. Subgroup analysis showed that LDL-C and SBP were reduced more effectively in postmenopausal women with metabolic syndrome. Genistein intake more than 6 months showed a greater effect on lowering cholesterol -0.76(-1.27, -0.24), SBP [-0.39(-0.70, -0.08)] and DBP -0.40(-0.81, -0.00) and increasing TG and LDL-C. This meta-analysis provides consistent evidence that genistein intake reduces the CVD risk factors of TC, LDL-C, and SBP significantly.  相似文献   
8.
BackgroundThe Flex VP is a longitudinal micro-incision catheter approved for vessel prepping of femoropopliteal arteries and arteriovenous fistulas. In this study, we evaluated the presence of deep dissections (adventitia) using IVUS in patients undergoing Flex VP followed by angioplasty (PTA) versus PTA alone.Methods17 patients (20 limbs) with femoropopliteal artery (FP) disease were prospectively and consecutively included (10 limbs received PTA followed by 10 limbs that received FLEX VP microincision catheter treatment followed by adjunctive PTA). Dissections post PTA, FLEX VP and FLEX VP+ PTA were evaluated using intravascular ultrasound (iDissection classification) and angiographically (NHLBI classification) by core laboratory. The evaluated segment of the vessel was prespecified at 10 cm at the most severe lesion location. Statistical differences were analyzed between the 2 groups at each appropriate procedural point for dissections, minimal luminal diameter (MLD), minimal luminal area (MLA), and residual stenosis. Statistical significance was determined by a p-value <0.05.ResultsBaseline demographics and angiographic variables were similar between the PTA vs FLEX VP + PTA groups with the exception of more males (87.5 % vs 33.3 %, p = 0.0274) and longer treated length (median 300 mm vs 150 mm, p = 0.0240) in the FLEX VP + PTA group. Lesion length, chronic total occlusions, angiographic and IVUS evaluated segment length for dissections, calcium severity and final balloon pressures and inflation duration were all similar between the 2 groups. Angiographic dissections were similar between the 2 groups but the increase in severe dissections from index to post POBA on IVUS (involving the adventitia) were significantly more for PTA when compared to FLEX VP + PTA (0 to 12 and 0 to 1 respectively, p = 0.0353). Bailout stenting was statistically similar for PTA as compared to FLEX VP + PTA per core lab evaluation (50 % vs 20 %, p = 0.3498). Minimal luminal area (MLA) gain by IVUS was similar between the 2 groups following FLEX VP + PTA vs PTA (7.4 mm2 vs 6.5 mm2, p = 0.7250). No serious major adverse events occurred in either group.ConclusionVessel prepping with the FLEX VP + PTA vs PTA yielded lower rates of adventitial dissections as seen on IVUS. The long-term outcomes of these findings remain unclear.  相似文献   
9.
目的探讨多元化联合教学模式在超声引导下疼痛介入治疗教学中的应用效果。方法选择2018年1月至2020年12月在北京大学第三医院疼痛科进修的30名医师作为研究对象,将其分为对照组与观察组;对照组采用常规教学模式;观察组采用多元化联合教学模式,比较两组医师技能考核成绩、教学质量评分和满意度评分。结果观察组医师技能考核成绩优良率为93.3%,高于对照组的73.3%(P<0.05);观察组医师对基础理论知识掌握、临床思维能力的提高、学习兴趣的激发、疾病诊治能力的提高4个方面的评分均高于对照组(P<0.01)。结论多元化联合教学模式可促进超声引导下疼痛介入治疗技能的提高,有利于提高学员的综合临床能力。  相似文献   
10.
肉瘤样肾细胞癌在肾细胞癌中极少见,术前准确判定肾癌类型对于确定手术切除的程度很有帮助,对肾肉瘤样癌手术切除需扩大手术范围,且由于其倾向于转移,术前还需对转移性病灶进行评估。所以增强超声医师对肾肉瘤样癌的认识对其治疗有重要意义。  相似文献   
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