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find Author "YANG Dan" 8 results
  • Role of diffusion tensor imaging and resting-state functional magnetic resonance imaging in early diagnosis of cognitive impairment related to white matter lesions

    White matter lesion (WML) of presumed vascular origin is one of the common imaging manifestations of cerebral small vessel diseases, which is the main reason of cognitive impairment and even vascular dementia in the elderly. However, there is a lack of early and effective diagnostic methods currently. In recent years, studies of diffusion tensor imaging (DTI) and resting-state functional magnetic resonance imaging (rs-fMRI) have shown that cognitive impairment in patients with WMLs is associated with disrupted white matter microstructural and brain network connectivity. Therefore, it’s speculated that DTI and rs-fMRI can be effective in early imaging diagnosis of WMLs-related cognitive impairment. This article reviews the role and significance of DTI and rs-fMRI in WMLs-related cognitive impairment.

    Release date:2019-11-25 04:42 Export PDF Favorites Scan
  • Effect of Age and Method of Preparing Endometrium on the Pregnancy Rate of Frozen-Thawed Embryo Transfer in Treatment of Infertility

    【摘要】 目的 探讨不同年龄段和不同内膜准备方法对冻融胚胎移植(FET)妊娠率的影响。 方法 回顾性分析2007年3月-2009年8月107例患者131个FET周期,比较不同年龄段、不同内膜准备方法的妊娠情况。 结果 ①lt;29岁、30~34岁、≥35岁患者的周期临床妊娠率分别为45.28%、37.88%、33.33%,比较无统计学意义(Pgt;0.05)。②自然周期和激素替代周期内膜准备,两种方法患者平均年龄、平均移植胚胎数、胚胎评分及胚胎细胞数比较无统计学意义(Pgt;0.05),但自然周期的胚胎种植率及周期临床妊娠率均明显低于激素替代周期(16.78%比29.21%;29.51%比50.00%),比较有统计学意义(Plt;0.05)。 结论 患者年龄不影响FET周期临床妊娠率,激素替代周期内膜准备的FET胚胎种植率及周期临床妊娠率明显高于自然周期。【Abstract】 Objective To analyze the effect of age and method of preparing endometrium on the pregnancy rate of frozen-thawed embryo transfer (FET) among infertile women. Methods Retrospective analysis was made on 131 FET cycles in 107 patients from March 2007 to August 2009. The relationship between pregnancy rate of FET and following factors were analyzed: age, the method of preparing uterus endometrium. Results ①There was no significant difference in pregnancy rate of FET among <29, 30 - 34, and ≥35 years old patients (45.28%, 37.88%, and 33.33%, respectively) (Pgt;0.05). ②There was no significant difference in patients’ age, the average embryo amount, embryo score, the cell amount in every embryo between the FET with hormone replacement therapy (HRT) and the FET with natural cycle (NC). The embryo implantation rate and pregnancy rate of FET with NC were lower significantly than those of FET with HRT (16.78% vs 29.21%; 29.51% vs 50.00%) (P<0.05). Conclusion Age might not influence pregnancy rate of FET. FET with HRT has higher implantation rate and pregnancy rate than FET with NC.

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  • Study on the inverse problem of diffuse optical tomography based on improved stacked auto-encoder

    The inverse problem of diffuse optical tomography (DOT) is ill-posed. Traditional method cannot achieve high imaging accuracy and the calculation process is time-consuming, which restricts the clinical application of DOT. Therefore, a method based on stacked auto-encoder (SAE) was proposed and used for the DOT inverse problem. Firstly, a traditional SAE method is used to solved the inverse problem. Then, the output structure of SAE neural network is improved to a single output SAE, which reduce the burden on the neural network. Finally, the improved SAE method is used to compare with traditional SAE method and traditional levenberg-marquardt (LM) iterative method. The result shows that the average time to solve the inverse problem of the method proposed in this paper is only 1.67% of the LM method. The mean square error (MSE) value is 46.21% lower than the traditional iterative method, 61.53% lower than the traditional SAE method, and the image correlation coefficient(ICC) value is 4.03% higher than the traditional iterative method, 18.7% higher than the traditional SAE method and has good noise immunity under 3% noise conditions. The research results in this article prove that the improved SAE method has higher image quality and noise resistance than the traditional SAE method, and at the same time has a faster calculation speed than the traditional iterative method, which is conducive to the application of neural networks in DOT inverse problem calculation.

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  • Research on inversion method of intravascular blood flow velocity based on convolutional neural network

    Blood velocity inversion based on magnetoelectric effect is helpful for the development of daily monitoring of vascular stenosis, but the accuracy of blood velocity inversion and imaging resolution still need to be improved. Therefore, a convolutional neural network (CNN) based inversion imaging method for intravascular blood flow velocity was proposed in this paper. Firstly, unsupervised learning CNN is constructed to extract weight matrix representation information to preprocess voltage data. Then the preprocessing results are input to supervised learning CNN, and the blood flow velocity value is output by nonlinear mapping. Finally, angiographic images are obtained. In this paper, the validity of the proposed method is verified by constructing data set. The results show that the correlation coefficients of blood velocity inversion in vessel location and stenosis test are 0.884 4 and 0.972 1, respectively. The above research shows that the proposed method can effectively reduce the information loss during the inversion process and improve the inversion accuracy and imaging resolution, which is expected to assist clinical diagnosis.

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  • A case report of bone marrow smear and culture for the diagnosis of Talaromyces marneffei infection and literature review

    ObjectiveTo explore the clinical diagnosis and treatment of Talaromyces marneffei (TM) infection by bone marrow examination, and to clarify the important role and significance of bone marrow smear and pathogenic examination.MethodsRetrospective analysis was conducted on a case of disseminated TM infection that was clearly diagnosed through bone marrow related examination. Literature review of TM infection was conducted by retrieving relevant case reports at home and abroad from 1990 to 2018.ResultsThe patient was a 23-year-old man with recurrent cough and onset of fever, superficial lymph node enlargement in multiple parts of the body, no abnormal chest CT sign, and poor efficacy in anti-infection treatment. The patient developed progressive abdominal pain, accompanied by systemic papulosis, decreased consciousness, and progressive decline of blood cells. The patient underwent bone marrow puncture surgery in our hospital, and developed circulatory and respiratory failure half an hour after surgery. TM was confirmed bybone marrow smear and pathogenic culture. In the literature review, 2 855 cases of TM infection were retrieved, among which the majority of cases were confirmed through blood and bone marrow related examination. The positive rate of bone marrow culture was significantly higher than that of blood culture (72.4% and 66.8%, respectively, P=0.007). Compared with bone marrow culture, the misdiagnosis and missed diagnosis rate of bone marrow smear microscopy was 27.6%. Patients diagnosed with TM infection by bone marrow examination had the highest HIV positive rate (95.7%).ConclusionsThe examination of bone marrow cells and the culture are of great clinical significance for the diagnosis of TM infection. TM infection should be identified in patients suspected of HIV positive with fever, lymph node enlargement and abnormal blood routine.

    Release date:2019-05-23 04:40 Export PDF Favorites Scan
  • Analysis of sputum flora in patients with acute exacerbation of chronic obstructive pulmonary disease basing on metagenomic next generation sequencing

    Objective To analyze the difference of sputum flora between acute exacerbation and stable chronic obstructive pulmonary disease (COPD) patients basing on metagenomic next generation sequencing (mNGS), and its relationship with clinical indicators. The role of sputum flora of COPD patients in unexplained deterioration was explored, so as to find a targeted treatment plan. Methods From December 2021 to June 2022, 54 COPD patients who had a history of smoking were recruited, including 25 patients in stable COPD (SCOPD group) and 29 patients in acute exacerbation (AECOPD group). The sputum was collected and sequenced by mNGS, and the difference of sputum flora between the two groups was compared. Results Compared with SCOPD group, the evenness of sputum flora (Shannon index) in AECOPD group decreased significantly (P=0.019, Mann-Whitney U test). At the phylum level, the relative abundance of Fusobacteria in AECOPD group was significantly lower than that in SCOPD group (Z=–2.669, P=0.008). At genus level, compared with SCOPD group, the relative abundance of Fusobacterium and Haemophilus in AECOPD group decreased significantly (Z=–3.062, P=0.002; Z=–2.143, P=0.032), and the relative abundance of Granulicatella increased significantly (Z=–2.186, P=0.029). At species level, the relative abundance of sputum Haemophilus parainfluenzae, Moraxella catarrhalis and Haemophilus influenzae in AECOPD group was significantly lower than that in SCOPD group (Z=–2.230, P=0.026; Z=–2.125, P=0.034; Z=–2.099, P=0.036). At the time of acute exacerbation of COPD, the relative abundance of Gemella in sputum was positively correlated with forced expiratory volume in first second/forced vital capacity (FEV1/FVC) and body mass index (r=0.476, P=0.009; r=0.427, P=0.021), which was negatively correlated with nutrition risk screening 2002 (r=–0.570, P=0.001). The relative abundance of Neisseria and Neisseria subflava was negatively correlated with GOLD grade (r=–0.428, P=0.020; r=–0.455, P=0.013). The relative abundance of Rothia aeria was posotively correlated with C-reactive peotein (r=0.388, P=0.038). Conclusions There are significant differences of sputum flora in phylum, genus and species level between stable and acute exacerbation COPD patients. The evenness of sputum flora in COPD patients in acute exacerbation is significantly lower than that in patients in stable stage. Fusobacteria, Fusobacterium, Gemella and Nesseria (Neisseria subflava) may play a beneficial role in COPD, while Rothia aeria may be associated with COPD exacerbation.

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  • Effect of Mongolian medicine fumigation combined with sciatic nerve and rectal probe pelvic floor electrical stimulation on muscle spasticity of cervical spinal cord injury

    ObjectiveTo observe the effect of Mongolian medicine fumigation combined with sciatic nerve and rectal probe electrical stimulation on muscle spasticity of spinal cord injury.MethodsBetween January 2012 and January 2018, a total of 65 patients with muscle spasticity after spinal cord injury were randomly divided into two group: the observation group (32 cases) and the control group (33 cases). The patients in the observation group were treated with Mongolian medicine (Wu Wei Gan Lu-Decoction) fumigation combined with sciatic nerve and rectal probe electrical stimulation, while the patients in the control group were treated with medicine, physical therapy, and exercise therapy. Both two groups were treated for 8 weeks. The patients were scored with Ashworth Score, American Spinal Injury Association (ASIA) score, and Barthel Index before and after treatment.ResultsThe pre-treatment ASIA scores (light touch sensation, pain sensation, and muscle strength) and Barthel Index of the two groups were not statistically significant (P>0.05). The post-treatment ASIA scores and Barthel Index of both groups performed significantly better than the pre-treatment levels (P<0.05). The post-treatment ASIA muscle strength item was 58.55±10.83 in the observation group and 50.69±11.32 in the control group (P<0.05). The post-treatment Barthel Index was 74.22±11.53 in the observation group and 68.46±9.92 in the control group (P<0.05). The effective rate in the observation group was significantly better than that in the control group (84.4% vs. 60.6%, P<0.05). Conclusion Mongolian medicine fumigation combined with sciatic nerve and rectal probe electric stimulation could improve the muscle spasticity of spinal cord injury and patients’ ability of daily life effectively.

    Release date:2019-05-23 04:49 Export PDF Favorites Scan
  • Management experience of radiology department of West China Hospital of Sichuan University in fighting against coronavirus disease 2019

    Coronavirus disease 2019 that started in Wuhan, Hubei Province in December 2019, has spread rapidly across China. Radiography provides an important basis for clinical diagnosis of coronavirus disease 2019 and plays a crucial role in fighting against the epidemic. In the face of public health emergencies, how to quickly set up a team for accurate prevention and control in the first time and how to carry out radiological examination and diagnosis ina scientific, orderly, safe and efficient manner are the key measures to support the hospital in effectively responding to the epidemic. This paper summarized the innovative management experience of the radiology department of West China Hospital of Sichuan University in the prevention and control of nosocomial infection and discipline construction in the fight against the outbreak of coronavirus disease 2019.

    Release date:2020-04-23 06:56 Export PDF Favorites Scan
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