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1.
目的 运用CT区分脾脏血管性病变与淋巴瘤。方法 回顾性分析20例经手术、穿刺病理学检查证实的脾脏病变的发病年龄、性别、脾脏指数、病变大小、数目、有无液化、钙化、强化幅度、强化方式等特征,并进行统计学分析。结果 20例脾脏病变中,11例血管性病变(6例海绵状血管瘤,3例窦岸细胞血管瘤,2例硬化性血管瘤样结节性转化),9例淋巴瘤;两组间发病年龄、病变大小、数目、有无液化、钙化等差异无统计学意义;两组间脾脏指数、动脉期强化幅度差异具有统计学意义(P<0.05)。5例海绵状血管瘤呈不均匀性强化,1例呈渐进性填充式强化,2例窦岸细胞血管瘤呈“雀斑征”,1例硬化性血管瘤样结节性转化呈“辐轮征”;9例淋巴瘤实质部分均呈均匀、轻中度强化。结论 脾脏血管性病变与淋巴瘤CT表现不同,CT有助于明确诊断。  相似文献   
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We report population prevalence rates of neural tube defects (NDT) and microcephaly (MIC) as well as levels of incorporated Cs137 by pregnant women in two areas of the Rivne Province of Ukraine, a northern half (Polissia) polluted by Chornobyl radiation and not‐Polissia areas. Monitoring of congenital malformations was conducted with adherence to methods adopted by a European surveillance network (EUROCAT). Incorporated Cs137 (Bq/kg) by pregnant women residing in the Polissia and not‐Polissia areas were obtained concurrently with prenatal ultrasound examinations. In Polissia, the incorporated Cs137 levels by pregnant women as well as the prevalence rates of NDTs and MIC are significantly higher than in not‐Polissia. In Polissia, the prevalence rates of NDTs and MIC are among the highest in Europe. The debate concerning the teratogenic impact of chronic exposures to low levels of ionizing radiation was re‐ignited by our 2010 report. Health agencies uphold the notion that exposure to Chornobyl radiation levels are too low to be teratogenic, which is inconsistent with our observations. Further investigations in Rivne by international teams can, we believe, contribute facts to the ongoing debate. Our monitoring system, experience and data can facilitate concurrent investigations of teratogenic risks from exposures to other sources of ionizing radiation, alcohol, folate, and zinc deficiencies, among other risk factors. Study of genomic impacts can likewise be undertaken.  相似文献   
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目的:探讨螺旋CT多时相扫描对肝细胞癌和血管瘤的鉴别诊断。材料和方法:对37例患者(肝癌16例,血管瘤21例)行螺旋CT平扫和增强扫描,分析其表现。结果:37例平扫均发现低密度灶。肝细胞癌在动脉期75%有显著增强,呈高密度,在门静脉期和延迟期则呈低密度;血管瘤54%动脉期有典型增强表现,门静脉期100%有增强,24%全部填充,延迟期91%为高密度或等密度。结论:肝细胞癌和血管瘤在螺旋CT多时相增强扫描中,各有其典型的CT表现,两者鉴别的关键是门静脉期。  相似文献   
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We propose a haphazard branching theory to support the concept of bronchopulmonary malinosculations, and we apply this theory to classify congenital bronchopulmonary vascular malformation (BPVM) based on the anatomical results we have found. Between January 1990 and December 1997, a total of 22 pediatric patients (10 male and 12 female), aged 2 days to 14 years (median, 19.6 months), with congenital BPVM were enrolled in this retrospective study. Study modalities include the clinical features and plain chest films (n = 22) plus at least two of the following: echocardiography (n = 13), barium esophagraphy (n = 2), bronchoscopy (n = 4), contrast bronchography (n = 8), high-resolution direct coronal CT (n = 1) and electron beam or ultrafast CT (n = 1) of the chest, MRI (n = 10), MRA (n = 1), contrast cineangiocardiography (n = 9), surgery (n = 11), or autopsy (n = 2). The salient clinical features were recurrent lung infections in 14 patients, acute respiratory distress in 13, associated cardiovascular malformations in 8, dextroversion in 7, congestive heart failure in 7, dextrocardia in 4, and complex congenital heart diseases in 4. There were abnormal openings (malinosculations) of the pulmonary airway in 20 patients: to an artery in 12, to a vein in 8, and to the lung parenchyma in 9. These 22 patients with congenital BPVM can be classified into bronchial malinosculation (10 cases), arterial malinosculation (2 cases), and bronchoarterial malinosculation (10 cases). Congenital BPVM can be classified in terms of bronchopulmonary malinosculation based upon a haphazard branching theory, in which abnormal communications between two independent systems (primitive foregut system and aortic-pulmonary arch system) occurred coincidentally rather than causally.  相似文献   
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三维超声对胎儿体表畸形的诊断价值   总被引:2,自引:0,他引:2  
目的:探讨三维超声成像在胎儿体表畸形诊断的临床价值。方法:利用三维超声仪对在我院进行产前检查的妊娠20~41周的3241例孕妇、共3277个胎儿进行二维及三维超声检查,统计并比较超声诊断与随访结果。结果:140例各种发育异常胎儿,其中体表畸形胎儿34例,二维超声诊断正确者21例,9例体表畸形胎儿二维超声检查不能作出明确诊断;三维超声进一步检查诊断正确者共30例;二维及三维超声检查误诊1例胎儿足内翻,生后证实正常,漏诊1例耳廓缺失、2例多指畸形,生后随访证实。三维超声对胎儿体表畸形检出的敏感性、特异性及准确性分别为90.91%、99.97%、99.88%;二维超声对胎儿体表畸形检出的敏感性、特异性及准确性分别为63.64%、99.97%、99.60%。结论:三维超声能直观显示胎儿体表结构,三维超声检查诊断胎儿体表畸形的敏感性、特异性及准确性高,是二维超声检查的重要补充,与二维超声联合应用,可提高胎儿体表畸形的检出率。  相似文献   
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Introduction Iniencephaly, a neural tube defect involving occiput and inion and combined with rachischisis of the cervical, thoracic spine, and retroflexion position of the head is a very rare congenital abnormality of the fetus–newborn with a 0.1–10 of 10,000 prevalence. This abnormality’s prognosis is thought to be dismal. This abnormality can be associated with other abnormalities such as anencephaly, encephalocele, hydrocephalus, cyclopia, absence of the mandible, cleft lip and palate, cardiovascular disorders, diaphragmatic hernia, renal abnormalities, overgrowth of the arms compared to the legs, and club food and gastrointestinal atresia. Discussion Most of the patients are dead born, and the others die in a few hours. There are only six previously documented long-term survivors. In our case, our patient with iniencephalic signs and findings is still living. She is 2 years old now. We think that this patient presents a mild form of iniencephaly.  相似文献   
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扩大经鼻蝶入路海绵窦的内镜解剖研究   总被引:1,自引:1,他引:0  
目的通过对扩大经鼻蝶窦入路的内镜解剖学研究,为临床应用提供形态学基础.方法在10具动脉灌注染料的成人尸头上模拟扩大经鼻蝶窦手术入路,测量海绵窦内重要结构与鞍底的距离.结果扩大经鼻蝶手术入路可清晰显示鞍底的骨膜、硬脑膜外层、海绵窦内侧壁,及海绵窦内的颈内动脉及其分支血管、动眼神经、滑车神经、展神经及视神经等结构.结论内镜下行扩大经鼻蝶手术入路可清晰显露海绵窦及其内的解剖结构,适用于鞍内病变侵犯海绵窦的外科治疗.  相似文献   
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