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111.
二维斑点追踪技术对糖尿病患者心脏舒缩功能的研究   总被引:1,自引:0,他引:1  
目的 运用二维斑点追踪技术(STI)评价糖尿病患者的心脏收缩和舒张功能.方法 对28例糖尿病无血管并发症(DM Ⅰ组),19例糖尿病合并血管并发症(DM Ⅱ组)及27例健康体健者(对照组)行常规二维超声,录取图像后导入EchoPAC分析软件,用斑点追踪技术对左室应变及扭转进行定量分析.结果 DM Ⅰ组及DM Ⅱ组与对照组比较,纵向应变和扭转角度峰值减小,扭转速度达峰时间缩短,解旋速度达峰时间延长、扭转速度峰值、解旋速度峰值及解旋率均减小,且随着并发症的出现差异更明显.结论 STI技术可以定量评价糖尿病患者的心脏收缩和舒张功能.  相似文献   
112.
Objective: To enrich small bioactive compounds from Mailuoning Injection factory effluene by polyether sulfoxide hollow fiber membrane. Methods: The retention rate of the common polymer (protein, tannin, starch, and pectin) and the permeability of the small molecule pharmacodynamic substance chlorogenic acid were the indicators, and the stop time and membrane type in ultrafiltration process were optimized. The temperature, pressure, and feed rate were investigated to determine the influence degree of each factor on the permeability and retention rate, and then the optimum process parameters of the ultrafiltration membrane process were optimized by using Box-Behnken design-response surface method. Results: The sequence of common polymer retention rate from high to low is: the influencing factor A (temperature), B (pressure), C (feed rate), and there was a negative correlation with the temperature. For the chlorogenic acid transmission rate, the influencing factor A (temperature) was larger than B (pressure), and C (feed rate) was lowest. There was a “∩” relationship between chlorogenic acid permeability and pressure at a certain temperature and rate. The results of optimized process were as follows: liquid temperature was 35 ℃, feed rate was 262 mL/min, and membrane pressure was 15.0 psi (1 psi = 6.895 kPa). The chlorogenic acid transmission rate was (91.470 ± 0.988)%, and polymer retention rate was (80.080 ± 2.296)%. The comprehensive score was (85.780 ± 1.641)% and RSD was 0.46%. There was a small difference between the two processes. Conclusion: Hollow fiber membrane, which is a sustainable and green resource utilization, has a good permeability for small bioactive compounds in wastewater, and has excellent retaining effect on common macromolecules. © 2019, Editorial Office of Chinese Traditional and Herbal Drugs. All right reserved.  相似文献   
113.
Previously unreported effects of tissue storage were recently observed in the authors' experimental magnetic resonance (MR) studies. To evaluate the effect of elapsed time after excision and storage temperature on tissue relaxation time measurements, tissue samples from the liver, pancreas, kidney, testis, spleen, and brain were obtained in rats. T1 and T2 were first measured within 5 minutes of excision, and between subsequent measurements, tubes were kept in a water bath at 40°C, at room temperature (28°C), or in an ice bath (4°C). Cellular and organellar integrity was assessed with electron microscopy and correlated with the MR findings. At 40°C (20-MHz spectrometer), the T1 of liver decreased from 280 msec ± 8 to 212 msec ± 10 during the first 60 minutes; the T1 of pancreas decreased from 276 msec ± 3 to 208 msec ± 2. Other tissues showed less than a 5% decrease in T1. T2 changes were smaller than T1 changes in all tissues. Electron microscopy of pancreatic acinar cells showed postmortem changes in mitochondria evolving over the first 60 minutes after death. Manganese loading experiments implicated mitochondrial manganese stores in the observed enhanced postmortem decrease in T1. This study calls into question reported relaxation time data for liver and pancreas. MR studies of excised tissues must account for time and temperature to prevent systematic experimental errors.  相似文献   
114.
Purpose. To assess the accuracy of different MR sequences for the detection of articular cartilage abnormalities in rheumatoid arthritis. Design and patients. Ten metacarpophalangeal joints and 10 metatarsophalangeal joints (specimens from arthritis patients undergoing ablative joint surgery) were examined with a fat-suppressed (FS) 3D FLASH, a FS 3D FISP, a FS 2D fast spin-echo T2-weighted, and a 2D FS spin-echo T1-weighted sequence. Each cartilage lesion and each cortical lesion was graded from 0 to 4 (modified Outerbridge staging system). Subsequently, the results of each sequence were compared with the macroscopic findings and statistically tested against each other. Results. The study shows that 3D gradient-echo sequences with fat suppression were best for imaging and grading of cartilage lesions in arthritis of the small joints of the hands and feet. Using 3D techniques, all grade 2, grade 3, and grade 4 lesions of cartilage or cortical bone were detected. Conclusion. FS 3D gradient-echo techniques were best for the detection and grading of hyaline cartilage and subchondral bone lesions in rheumatoid arthritis. MRI has a great potential as an objective method of evaluating cartilage damage and bone erosions in rheumatoid arthritis.  相似文献   
115.
孤独症谱系障碍(ASD)是一组以社交障碍为主的神经发育性疾病,患病率呈逐年增加的趋势,且未见特效疗法,为此早诊断、早干预尤为重要.近些年,通过眼动技术研究,发现ASD在生命早期便存在异常的注视模式,有望将此作为ASD早期检测和诊断的生物标志物.现从ASD儿童异常的眼动模式、研究范式、大脑相关区域的联系及面孔加工四个方面,对ASD儿童运用眼动技术的研究文献进行梳理总结,阐述最新研究成果.  相似文献   
116.
Schwannomatosis is characterized by multiple non-intradermal schwannomas with patients often presenting with a painful mass in their extremities. In this syndrome malignant transformation of schwannomas is rare in spite of their large size at presentation. Non-invasive measures of assessing the biological behavior of plexiform neurofibromas in neurofibromatosis type 1 such as positron emission tomography (PET), CT scanning and MRI are well characterized but little information has been published on the use of PET imaging in schwannomatosis. We report a unique clinical presentation portraying the use of PET imaging in schwannomatosis. A 27-year-old woman presented with multiple, rapidly growing, large and painful schwannomas confirmed to be related to a constitutional mutation in the SMARCB1 complex. Whole body PET/MRI revealed numerous PET-avid tumors suggestive of malignant peripheral nerve sheath tumors. Surgery was performed on multiple tumors and none of them had histologic evidence of malignant transformation. Overall, PET imaging may not be a reliable predictor of malignant transformation in schwannomatosis, tempering enthusiasm for surgical interventions for tumors not producing significant clinical signs or symptoms.  相似文献   
117.
目的探讨多排螺旋CT(MSCT)对气管憩室的诊断价值。方法选取分析68例气管憩室的临床及影像学资料。结果本组68例共发现气管憩室82个,其中59例为单发,9例为多发(≥2个),单发占86.76%,多发占13.24%,多发气管憩室中5例为2个憩室,3例为3个憩室,1例为4个憩室;本组气管憩室大小不等,其中最大直径44.00 mm,最小直径1.50 mm,平均直径为26(23~35)mm。82个气管憩室形状多样,圆形或类圆形(囊腔样)为62个,气泡样10个,烧瓶样6个,凹槽样2个,三角样2个;MSCT能显示气管憩室与气管为单一细管或多个管道相通,其中2例气管憩室合并感染,本组68例中有慢性支气管炎、肺气肿或慢性支气管炎合并肺气肿的病例共为38例,占55.88%。结论MSCT可以清晰显示气管憩室与气管的通道、气管憩室的部位、数量、形状和内容物等情况,对气管憩室的诊断有重要价值。  相似文献   
118.
郭玉婷  张雪峰 《武警医学》2022,33(9):764-768
目的 探讨人工辅助生殖技术(assisted reproductive technology, ART)及自然受孕孪生早产儿临床结局。方法 收集医院2015-01至2020-12出生的孪生早产儿,共计364例(182对),根据受孕方式不同分为ART组和自然受孕组,ART组孪生156例(78对),自然受孕组孪生208例(104对)。对两组孪生早产新生儿期并发症情况进行回顾性分析,收集母孕期一般情况、并发症、孪生早产儿出生时孕周、Apgar评分、孪生体重及体重差值、出生后合并呼吸窘迫综合征(respiratory distress syndrome, RDS)、新生儿宫内感染性肺炎、新生儿低血糖症、院内感染、应用呼吸支持情况、应用中心静脉置管(PICC和(或)UVC)、Ⅲ~Ⅳ度颅内出血、动脉导管未闭(≥3.0 mm)、支气管肺发育不良(bronchopulmonary dysplasia, BPD)、早产儿视网膜病变(retinopathy of prematurity, ROP)、住院天数、应用静脉营养时间等信息,比较两组之间的差异。结果 ART组产妇年龄大于35岁为26.3%,高于自然...  相似文献   
119.

Context

Laser treatment of benign prostatic obstruction (BPO) has become more prevalent in recent years. Although multiple surgical approaches exist, there is confusion about laser-tissue interaction, especially in terms of physical aspects and with respect to the optimal treatment modality.

Objective

To compare available laser systems with respect to physical fundamentals and to discuss the similarities and differences among introduced laser devices.

Evidence acquisition

The paper is based on the second expert meeting on the laser treatment of BPO organised by the European Association of Urology Section of Uro-Technology. A systematic literature search was also carried out to cover the topic of laser treatment of BPO extensively.

Evidence synthesis

The principles of generation of laser radiation, laser fibre construction, the types of energy emission, and laser-tissue interaction are discussed in detail for the laser systems used in the treatment of BPO. The most relevant laser systems are compared and their physical properties discussed in depth.

Conclusions

Laser treatment of BPO is gaining widespread acceptance. Detailed knowledge of the physical principles allows the surgeon to discriminate between available laser systems and their possible pitfalls to guarantee high safety levels for the patient.  相似文献   
120.
银以金属银、硝酸银、磺胺嘧啶银等多种形式应用于烧伤及多种细菌感染的治疗。随着抗生素的发现与应用,这些银复合物的应用显著下降。近年来,纳米技术因可调节金属尺寸至纳米级,使金属的化学、物理与光学性质有了极大的改变.纳米级的金属银成为一种潜在的抗菌剂。由于抗生素耐药性的发生,纳米银的应用具有广阔前景。  相似文献   
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