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991.
目的探讨2019新型冠状病毒肺炎(COVID-19)影像学表现。方法根据纳入标准和排除标准收集2020年1月20日至2月5日来自全国多家医院确诊COVID-19病例130例,按分布特点进行分型,分析其影像学特征。结果(1)分布:单侧14例(10.7%),双侧116例(89.3%);胸膜下型(102例78.4%),小叶核心型99例(76.1%),弥漫型8例(6.1%);(2)数目:单发病灶9例(6.9%),多发病灶113例(86.9%),弥漫8例(6.1%);(3)密度:仅为磨玻璃影(GGO)70例(53.8%),GGO与实变影兼有60例(46.2%);(3)伴随征象:血管增粗100例(76.9%),胸膜平行征98例(75.3%),"细网格征"100例(76.9%),"晕征"13例(10%),"反晕征"6例(4.6%),3例胸腔积液(2.3%),2例肺气囊(1.5%)。未见空洞。35患者行CT复查,21例(60%)好转,14例(40%)加重。结论COVID-19影像学特点主要以胸膜下及小叶核心分布为主,两者均可融合成片,重症者发展为双肺弥漫;最有价值的特征是"胸膜平行征";恢复期表现为边缘收缩的实变影,支气管扩张,胸膜下线或纤维条索影。 相似文献
992.
Feasibility of one‐step endoscopic metal stenting for distal malignant biliary obstruction
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995.
Oral Diseases (2012) 18 , 728–733 Background: The value of chairside adjunctive tests in the detection of oral potentially malignant disorders (OPMDs) remains uncertain. Objectives: To determine the effectiveness of toluidine blue in detecting leukoplakia and erythroplakia and its accuracy in identifying cases with oral epithelial dysplasia. Materials and Methods: Ninety‐two patients attending two oral medicine clinics in London, presenting with white and red patches of the oral mucosa, were investigated by the application of toluidine blue. Eighty‐two patients were clinically diagnosed as OPMDs and 10 were frictional keratoses. A surgical biopsy was performed to assess epithelial dysplasia. Results: Of 64 oral leukoplakias, 34 (53.1%) were positive for toluidine blue and among nine erythroplakias seven stained positive. Of 41 oral dysplasia cases, a little more than half of the lesions (n = 23) were stain positive, an estimated sensitivity of 56.1%. TBlue test had a higher sensitivity for detecting higher‐grade dysplastic lesions (5/8 moderate dysplasia, sensitivity 62.5%; 5/7 severe dysplasia; sensitivity 71.4%) compared with lower grades of dysplasia, but the differences were not significant (P = 0.60). Conclusions: We report here the utility of TBlue for the detection of oral leukoplakia and erythroplakia. The test has the potential to detect OPMDs and yielded a sensitivity of 56.1% and specificity of 56.9% to detect oral epithelial dysplasia. 相似文献
996.
肿瘤坏死因子(TNF)相关凋亡诱导配体(TRAIL)是 TNF 家族中继 TNF 和 Fas 抗原配体之后发现的又一重要的新成员,具有诱导肿瘤细胞、转化细胞等发生凋亡而对正常细胞无凋亡诱导作用的特点.自发现至今,因其对肿瘤细胞的选择性而被人们关注并逐渐发展成为靶向肿瘤治疗研究的热点.本文将对TRAIL的特性,TRAIL及其受体诱导凋亡的分子机制,以及TRAIL为靶点的基因治疗和作为抗肿瘤药物在各类肿瘤尤其是头颈部恶性肿瘤中的应用进展及前景展开综述. 相似文献
997.
目的 评价超声内镜(EUS)对胃癌患者术前TNM分期的准确性.方法 126例行外科手术治疗的胃癌患者,于术前1周行EUS和腹部螺旋CT检查,确定肿瘤浸润深度(T)、淋巴结转移(N)、远处转移(M)等分期情况,并与术后病理TNM分期进行对照,以评价EUS对TNM分期的准确性.数据处理采用配对x2检验.结果 与术后病理结果比较,EUS对胃癌T1、T2、T3、T4分期的准确率分别为84.6%、14/18、82.0%、85.7%;EUS对胃癌N0、N1、N2、N3分期的准确率分别为74.2%、75.0%、57.9%、5/17.螺旋CT对胃癌N0、N1、N2、N3分期的准确率分别为80.6%、75.0%、73.7%、12/17.EUS与螺旋CT对N0和N1分期判断的准确率接近,而对N2和N3分期的判断,螺旋CT较EUS有明显优势(x2=4.89,P=0.027;x2=13.88,P<0.01).对于胃癌远处转移M1分期的比较,EUS与螺旋CT的准确率分别为36.4%、95.5%,螺旋CT对M1的判断优于EUS(x2=7.90,P=0.001).结论 EUS对胃癌术前T分期具有较高的临床应用价值,而对淋巴结转移的N2、N3分期及远处转移的M分期的准确性有待提高.为获得较准确的术前TNM分期以指导治疗方案的选择,有必要联合螺旋CT检查. 相似文献
998.
The 5‐HT4 receptor levels in hippocampus correlates inversely with memory test performance in humans
Mette Ewers Haahr Patrick Fisher Klaus Holst Karine Madsen Christian Gaden Jensen Lisbeth Marner Szabols Lehel William Baaré Gitte Knudsen Steen Hasselbalch 《Human brain mapping》2013,34(11):3066-3074
The cerebral serotonin (5‐HT) system is involved in cognitive functions such as memory and learning and animal studies have repeatedly shown that stimulation of the 5‐HT type 4 receptor (5‐HT4R) facilitates memory and learning and further that the 5‐HT4R modulates cellular memory processes in hippocampus. However, any associations between memory functions and the expression of the 5‐HT4R in the human hippocampus have not been investigated. Using positron emission tomography with the tracer [11C]SB207145 and Reys Auditory Verbal Learning Test we aimed to examine the individual variation of the 5‐HT4R binding in hippocampus in relation to memory acquisition and consolidation in healthy young volunteers. We found significant, negative associations between the immediate recall scores and left and right hippocampal BPND, (p = 0.009 and p = 0.010 respectively) and between the right hippocampal BPND and delayed recall (p = 0.014). These findings provide evidence that the 5‐HT4R is associated with memory functions in the human hippocampus and potentially pharmacological stimulation of the receptor may improve episodic memory. Hum Brain Mapp 34:3066–3074, 2013. © 2012 Wiley Periodicals, Inc. 相似文献
999.
Primary malignant melanoma arising in the oesophagus is a rare condition with a dismal prognosis. The diagnosis is often made following surgical resection even though the endoscopic features may be pathognomonic. The classical treatment is oesophagectomy even though the advanced disease stage at the time of presentation and aggressive biological behaviour of the tumour usually results in a fatal outcome. We report the case of a male patient initially diagnosed with squamous oesophageal carcinoma and treated with conventional neo-adjuvant chemo-radiotherapy. Poor clinical and radiological response resulted in a review of the original histology confirming a diagnosis of primary malignant melanoma of the oesophagus. The subsequent alteration in management conferred the patient an improved quality of life. A short review of the literature on primary malignant melanoma of the oesophagus supplements this case report. 相似文献
1000.
P.E. Müller H.R. Dürr A. Nerlich C. Pellengahr M. Maier V. Jansson 《Acta chirurgica Belgica》2013,113(3):341-344
Malignant transformation of solitary enchondromas of the hand to secondary chondrosarcomas is extremely rare. We report a case of a recurrent chondromatous tumor of the hand that initially presented with the typical histology of a cellular enchondroma of the small tubular bones but with clinical and radiological signs of malignancy. After development of a single pulmonary metastasis of a chondromyxoid tumor a malignant transformation of the primary enchondroma of the hand must be assumed. 相似文献