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李玉霞 《中国医学文摘.耳鼻咽喉科学》2021,(2):142-143,146
目的探讨磁共振结合高分辨率CT在中耳乳突炎患者术前评估中的临床应用。方法选取我院2018年11月~2020年12月接收患有中耳乳突炎的患者40例为研究对象,所有患者均采用磁共振以及高分辨率CT进行诊断检查,比较两组患者诊断后手术特征显示度。结果诊断后,磁共振联合高分辨率CT检查图像显示度高于单独使用磁共振或高分辨率CT诊断(P<0.05)。结论使用磁共振结合高分辨率CT对中耳乳突炎患者进行术前评估,显示度较高,提高诊断准确度,值得推广。 相似文献
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《中国现代医生》2020,58(7):44-46+50+封三
目的 探讨超高分辨率眼前节OCT在结膜增生性疾病诊断中的应用效果。方法 选取2017年1月~2018年12月浙江大学附属第一医院及北仑分院眼科门诊收治的150例(150眼)结膜增生性疾病患者作为研究组。另选同期在我院进行体检的结膜正常者80例(80眼)作为对照组。统计分析超高分辨率眼前节OCT在睑裂斑,翼状胬肉及鳞状上皮瘤等结膜增生性疾病中临床诊断与病理诊断的符合率。观察分析睑裂斑,翼状胬肉及鳞状上皮瘤等结膜增生性疾病的特征性表现。结果 150例(150眼)结膜增生患者临床诊断为睑裂斑患者30例(30眼),翼状胬肉患者100例(100眼),以及眼表鳞状细胞瘤的患者20例(20眼)。与病理学诊断相比,UHR-OCT诊断睑裂斑诊断符合率为100.00%(30/30),翼状胬肉诊断符合率100.00%(98/98),眼表鳞状细胞瘤诊断符合率为90.91%(20/22),经统计学处理,差异无统计学意义(P0.05)。睑裂斑患者图像特征:生长在角巩膜缘处停止,且角膜上未见隆起,与前弹力层间未见高反射信号,与巩膜间未见明显分界。翼状胬肉患者图像特征:结膜上皮厚度轻度增厚,上皮层表现为中等程度的高反射,角膜上皮与前弹力层间表现为较高程度的高反射信号。OSSN患者图像特征:结膜上皮增厚,呈高反射,结膜正常上皮与异常上皮转变突然,无过渡区域,深部组织间上皮内可见瘤变。结论 超高分辨率眼前节OCT在结膜增生性疾病的诊断中具有较高的准确性,且影像特征明显,具有广阔的临床应用前景。 相似文献
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目的利用UPLC-LTQ-Orbitrap-MS技术对刺果番荔枝叶的化学成分进行定性分析。方法采用Waters Acquity UPLC HSS T 3色谱柱(2.1 mm×100 mm,1.8μm),流动相为0.1%甲酸水(A)和乙腈(B)梯度洗脱,流速为0.3 mL/min,进样量2μL,在电喷雾正负离子模式下采集数据。经Reaxys数据库检索番荔枝属类化合物信息,通过质谱信息比对各化合物的m/z值、保留时间、质谱特征碎片等,并结合文献数据对鉴定的化合物进行验证。结果根据各化合物的特征裂解规律,从刺果番荔枝叶中共鉴定出45个化合物,包括16个生物碱类,14个番荔枝内酯类,7个黄酮类和8个其他类化合物,其中以番荔枝内酯类和生物碱类成分居多,与文献报道番荔枝内酯与生物碱类化合物是发挥抗癌的主要活性成分一致。结论利用UPLC-LTQ-Orbitrap-MS技术对刺果番荔枝叶中的化学成分进行了快速、准确的定性分析,为刺果番荔枝叶的提取分离与药效物质基础的研究提供依据。 相似文献
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目的 研究miR-200、miR-155及血管新生因子与原因不明复发性流产(unexplained recurrent spontaneousabortion,URSA)的相关性分析。 方法 选择2015年3月—2018年1月在青岛市妇女儿童医院妇产科就诊的URSA患者作为URSA组、要求终止妊娠的正常早孕患者作为对照组,检测绒毛组织中微小RNA(microRNA, miR)miR-200、miR-155、血管内皮生长因子(vascular endothelial growth factor,VEGF)、可溶性FMS样酪氨酸激酶1(soluble FMS like tyrosine kinase-1,sFlt-1)的表达量及血清中VEGF、sFlt-1的含量,对miR-200、miR-155靶向结合VEGF、sFlt-1进行生物信息学分析。 结果 URSA组的绒毛组织中miR-200(1.78±0.32 vs. 0.91±0.15)、sFlt-1(1.87±0.35 vs. 1.06±0.21)的相对表达量及血清中sFlt-1的含量[(12.39±2.31)ng/ml vs. (6.51±0.95)ng/ml]均高于对照组,差异有统计学意义(均P<0.05)。绒毛组织中miR-155相对表达量(0.60±0.10 vs. 0.93±0.16)、VEGF mRNA相对表达量(0.59±0.09 vs. 1.02±0.16)及蛋白表达量(0.62±0.07 vs. 1.04±0.18)、血清中VEGF的含量[(601.25±94.39)ng/ml vs. (935.12±132.47)ng/ml]低于对照组,差异有统计学意义(均P<0.05);URSA组患者绒毛组织中miR-200的表达量与血清中VEGF的含量、绒毛组织中VEGF的表达量均呈负相关,绒毛组织中miR-155的表达量与血清中sFlt-1的含量和绒毛组织中sFlt-1的表达量均呈负相关;miR-200、miR-155分别靶向结合VEGF、sFlt-1基因的3’UTR。 结论 miR-200表达增多、miR-155表达减少与URSA发生有关,miR-200靶向VEGF、miR-155靶向sFlt-1是介导该过程的可能机制。 相似文献
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Daisuke Ishii Daisuke Matsuzawa Shingo Matsuda Haruna Tomizawa-Shinohara Chihiro Sutoh Eiji Shimizu 《The International journal of neuroscience》2019,129(1):1-9
Adolescence is a vulnerable period for developing anxiety-related mental disorders such as post-traumatic stress disorder (PTSD), which requires a long-term course of therapy when a traumatic event has been experienced during childhood. However, the biological mechanism underlying these age-dependent characteristics remains unclear. In the present study, we used early adolescent, late adolescent and adult (4-, 8-, and 15-week old) male mice to examine age differences in fear memory, fear extinction, and spontaneous recovery of fear. We also measured the activation of extracellular signal-regulated kinase (ERK) 2 in the dorsal hippocampus (dHip) and the basolateral amygdala (BLA) following a spontaneous recovery test. Our major findings were as follows: (1) early adolescent and adult mice did not recover the fear response; only late adolescent mice recovered the fear response. (2) The ERK2 in the dHip was more activated after the spontaneous recovery test in late adolescent mice than in adult mice, and the ERK2 in the BLA was more activated after the spontaneous recovery test in adult mice than in late adolescent mice. These results suggest that there exists a unique period in which spontaneous recovery occurs and that these late adolescent behavioral signatures may be related to alteration in the ERK2 phosphorylation in the dHip and BLA. 相似文献
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Outcome of conservative treatment of primary vesicoureteral reflux in 87 Thai children in a single center 总被引:1,自引:0,他引:1
PRAYONG VACHVANICHSANONG PORNSAK DISSANEEWATE APIRADEE LIM ALAN GEATER 《International journal of urology》2006,13(11):1393-1397
AIM: To evaluate the outcome of primary vesicoureteral reflux (VUR) using conservative treatment. METHODS: Eighty-seven children with primary VUR who had been treated with a conservative medical regimen and monitored through a yearly cystogram were recruited for the study. The study was conducted at the Pediatric Nephrology Clinic in Songklanagarind Hospital, the major tertiary care center in southern Thailand. Statistical analyses using Kaplan-Meier survival curves, chi-squared test, Fisher's exact test and multivariate analysis with Cox regression were performed. RESULTS: The study group consisted of 41 boys and 46 girls, with a total of 133 VUR. The age of the boys was significantly lower than that of the girls (P < 0.001). Resolution of the low grades (grades I-III) of VUR was significantly more frequent than that of the high grades (grades IV-V) (68/95, 72%vs 14/38, 37%; P < 0.001). Using the Kaplan-Meier survival analysis and log-rank test, the resolutions of VUR in boys versus girls, and age <1 years versus >or=1 years were not significantly different (P = 0.2252 and 0.4756, respectively). Low-grade VUR and unilateral VUR had significantly higher probabilities of resolution than high-grade VUR and bilateral VUR, respectively (P = 0.0041 and 0.0467, respectively). Multivariate Cox regression analysis indicated that among low-grade VUR, boys and unilateral VUR had significantly higher probabilities of resolution. Among the high-grade VUR, neither sex nor laterality had a significant effect on the probabilities of VUR resolution. CONCLUSION: This study offers more evidence that children with low-grade VUR have a higher chance of reflux resolution if they are boys and have only unilateral VUR. There is still no good guide for resolution of reflux in children with high-grade VUR. 相似文献
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m. fox † r. sweis † t. wong † & a. anggiansah 《Neurogastroenterology and motility》2007,19(10):798-803
Oesophageal spasm presents with dysphagia and chest pain. Current treatments are limited by poor efficacy and side effects. Studies in health and oesophageal dysmotility show that sildenafil reduces peristaltic pressure and velocity; however the clinical efficacy and tolerability in symptomatic oesophageal spasm remains uncertain. We provided open-label sildenafil treatment to two patients with severe, treatment resistant symptoms associated with oesophageal spasm. The effects of sildenafil on oesophageal function and symptoms were documented by high resolution manometry (HRM). Patients were followed up to assess the efficacy of maintenance treatment with sildenafil b.i.d. HRM revealed focal and diffuse spasm in the smooth muscle oesophagus that were associated with symptoms in both cases, especially on swallowing solids. Lower oesophageal sphincter function was normal. A therapeutic trial of 25-50 mg sildenafil suppressed oesophageal contraction almost completely for water swallows; however effective, coordinated peristalsis returned with reduced frequency of spasm for solid swallows. Dysphagia and chest pain resolved during the therapeutic trial and efficacy was maintained on maintenance treatment with 25-50 mg sildenafil b.i.d. without troublesome side effects. This report shows that sildenafil can improve oesophageal function and relieve dysphagia and chest pain in patients with oesophageal spasm in whom other treatments have failed. 相似文献
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T Jaermann K P Pruessmann A Valavanis S Kollias P Boesiger 《Magnetic resonance in medicine》2006,55(2):335-342
Limited spatial resolution is a key obstacle to the study of brain white matter structure with diffusion tensor imaging (DTI). In its frequent implementation with single-excitation spin-echo echo-planar sequences, DTI's ability to resolve small structures is strongly restricted by T2 and T2* decay, B0 inhomogeneity, and limited signal-to-noise ratio (SNR). In this work the influence of sensitivity encoding (SENSE) on diffusion-weighted (DW) image properties is investigated. Computer simulations showed that the PSF becomes narrower with increasing SENSE reduction factors, R, enhancing the intrinsic resolution. After a brief theoretical discussion, we describe the estimation of SNR on a pixel-by-pixel basis as a function of R. The mean image SNR behavior is manifold: SENSE is capable of increasing SNR efficiency by reducing the echo time (TE). Each SNR(R) curve reveals a maximum that depends on the amount of partial Fourier encoding used. The overall best SNR efficiency for an eight-element head coil array and a b-factor of 1000 s/mm2 is achieved at R = 2.1 and partial Fourier encoding of 60%. In vivo tensor maps of volunteers and a patient, with an in-plane resolution of 0.78 x 0.78 mm2, are also presented to demonstrate the practical implementation of the parallel approach. 相似文献