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991.
目的:在大鼠血管钙化模型上,探讨醛固酮(aldosterone,Aldo)在血管钙化中的作用及其可能机制。方法:肌注维生素D3和灌胃尼古丁(VDN)诱导大鼠血管钙化,运用von Kossa染色、原子吸收测定钙含量、45Ca2+沉积及碱性磷酸酶(ALP)活性测定判断血管钙化程度,半定量RT-PCR方法测定骨桥蛋白(OPN)mRNA水平;放射免疫法测定血浆和血管组织血管紧张素Ⅱ(AngⅡ)和Aldo含量。结果:VDN处理组大鼠血管von Kossa染色见平滑肌细胞内和细胞间基质有大量棕黑色颗粒聚集;主动脉钙含量较对照组高5.8倍(P<0.01);血管组织45Ca2+聚积和ALP活性分别较对照组高3倍和2.5倍(P<0.01);血管OPN mRNA表达明显上调58%(P<0.01);AngⅡ和Aldo含量分别较对照组高58%和80%(P<0.01)。运用血管紧张素转换酶抑制剂(ACEI)和Aldo受体阻断剂可明显改善上述指标变化,与单纯VDN处理组大鼠相比较,VDN+captopril组主动脉钙含量、45Ca2+聚积及ALP活性分别较单纯钙化组低37%、59%和62%(均P<0.01)。而VDN+spironolactone组分别低32%、44%和60%(均P<0.01)。血管OPN mRNA水平亦较单纯钙化组低30%和29%(P<0.01)。结论:VDN诱导的血管钙化大鼠血管组织AngⅡ和Aldo生成增加,ACEI和Aldo受体阻断剂明显减轻血管钙化,提示Aldo促进血管钙化并参与钙化发生。 相似文献
992.
Dipinder S Keer Paul Jeon Mark R Borgaonkar Stefan Potoczny 《Journal canadien de gastroenterologie》2010,24(6):355-358
Cavitating mesenteric lymph node syndrome (CMLNS) is a rare complication of celiac disease. Globally, only 36 cases of CMLNS have been reported to date. The present article reports an incidence of its unique pathology and possible complications of celiac disease, followed by a review of the syndrome. A case involving a 51-year-old man with celiac disease who was referred to hospital because of a non-tender abdominal mass is described. Plain film x-ray of the abdomen revealed fine curvilinear calcifications in the left lower quadrant. A complex, cystic-appearing, lobulated mass with somewhat echogenic walls most consistent with calcifications was revealed on subsequent ultrasound (US) imaging. Colour Doppler imaging showed no evidence of vascularity within the lesion. Computed tomography (CT) imaging showed a thin rim of calcification in the walls of multiple cystic components. Enhanced magnetic resonance (MR) imaging revealed a mixed solid and cystic multiloculated mass, with fat-fluid layers originating from the root of the small bowel mesentery. A CT-guided biopsy was performed. The fine-needle aspirate revealed calcified matter with no associated cellular material. No malignant cells were seen; CMLNS was established as the diagnosis. To the authors’ knowledge, there are no previous reports in the literature describing the finding of rim calcification on US or MR imaging in the setting of CMLNS. CMLNS is an important diagnosis to consider, particularly in patients with a history of celiac disease. The finding of rim calcification on US in the setting of cavitating mesenteric adenopathy should prompt further diagnostic imaging studies such as CT or MR imaging. These may lead to additional pathology studies such as a CT-guided biopsy to further characterize the lesion at the cellular level, to investigate potential malignancy and to further guide follow-up and patient management. 相似文献
993.
目的:对超声检查在乳腺钙化性病变中的临床价值以及优势进行分析探究.方法:选取孝昌县第一人民医院2019年10月—2020年10月收治的100例疑似乳腺钙化性病变患者,所有患者均进行X线检查和B超检查.以手术后病理诊断结果为金标准,对比两种方法的诊断结果.结果:超声检查诊断特异度与X线检查对比差异无统计学意义(P>0.0... 相似文献
994.
Zubler C Mengiardi B Schmid MR Hodler J Jost B Pfirrmann CW 《European radiology》2007,17(6):1603-1610
The purpose was to assess the diagnostic performance of MR arthrography to diagnose calcific tendinitis of the shoulder and
to assess the reasons for diagnostic errors. Standard MR arthrograms of 22 patients with calcific tendinitis and 61 controls
were retrospectively analyzed by two independent and blinded radiologists. All cases were consecutively collected from a database.
Conventional radiographs were available in all cases serving as gold standard. The supraspinatus was involved in 16, the infraspinatus
in four and the subscapularis in two patients. All diagnostic errors were analyzed by two additional readers. Reader 1 correctly
detected 12 of the 22 shoulders with and 42 of the 61 shoulders without calcific tendinitis (sensitivity 0.55, specificity
0.66). The corresponding values for reader 2 were 13 of 22 and 40 of 61 cases (sensitivity 0.59, specificity 0.69). Inter-rater
agreement (kappa-value) was 0.42. Small size of the calcific deposits and isointensity compared to the surrounding tissue
were the most important reasons for false negative results. Normal hypointense areas within the supraspinatus tendon substance
and attachment were the main reason for false positive results. In conclusion, MR arthrography is insufficient in the diagnosis
of calcific tendinitis. Normal hypointense parts of the rotator cuff may mimic calcific deposits and calcifications may not
be detected when they are isointense compared to the rotator cuff. Therefore, MR imaging should not be interpreted without
corresponding radiographs. 相似文献
995.
目的研究环氧氯丙烷对去细胞生物瓣膜钙化的影响。方法采用去垢剂和胰蛋白酶消化制备的去细胞猪主动脉瓣膜支架作为对照组,用3%环氧氯丙烷处理24h的去细胞猪主动脉瓣膜支架作为实验组。将培养的人骨髓基质干细胞(hBMSCs)种植于去细胞支架上,分别行Western blot及原位杂交方法测定人骨髓基质干细胞分泌基质金属蛋白酶-2,9(MMP-2,9)的功能。结果人骨髓基质干细胞在实验组去细胞瓣膜表面生长良好,MMP-2,9的表达比对照组降低,有统计学意义(P〈0.05)。结论环氧氯丙烷处理的去细胞猪主动脉瓣膜支架,可以抑制人骨髓基质干细胞的MMP-2,9的表达,对防止去细胞猪主动脉瓣膜支架钙化的形成有一定作用。 相似文献
996.
周围型肺癌钙化的CT表现及鉴别诊断意义 总被引:1,自引:0,他引:1
目的 评价周围型肺癌钙化的CT征象及诊断意义。材料与方法 98例经CT检查并有病理证实的周围肺癌中,17例可见钙化。其中腺癌10例,鳞癌5例,肺光癌2例。用2-3mm薄层扫描评价的钙化征象。结果 肺癌钙化征象的CT形态有三种:(1)细点状钙化:12例,其中腺癌6例,鳞癌4例,肺泡癌2例。钙化呈细小点或沙粒状偏心分布。(2)斑片状钙化:3例,其中腺癌2例,鳞癌1例。钙化呈不规则斑片状,偏心分布。(3)结节状钙化:2例均为腺癌,1例为单发结节,另1例为多发结节。结论 CT上肺结节或肿块内出现钙化,尤其是细点状钙化不能作为排除肺癌的指征,而应结合其它CT征象才能作出鉴别诊断。 相似文献
997.
目的探讨钼靶X线对指导乳腺无肿块型簇状钙化离体标本术中病理取材的价值。方法65例常规钼靶X线乳腺摄影显示无明显肿块形成的簇状钙化灶且临床不能触及肿堍BI—RADS(乳腺影像报告和数据系统)分级为Ⅲ~Ⅳ级且病灶钙化范围小于2cm^2的患者,在麻醉下行病灶区域性切除,术中离体标本依靠钼靶X线摄影再次定位,以大头针针尖标示簇状钙化中心位置,指导病理医生取材并活检。结果65例离体标本共行69次钼靶X线摄影,65例病灶均能成功定位并准确获取病理标本,最终病理定性诊断。病理示乳腺癌21例(其中浸润性导管癌11例,早期浸润性导管癌6例,导管内原位癌4例),立即行相应手术治疗;导管增生性病变42例(普通型导管增生24例;平坦型上皮非典型增生9例;非典型导管增生6例,导管内乳头状瘤3例);纤维腺瘤2例。乳腺癌检出率为32.3%,诊断准确率100%。结论钼靶X线指导乳腺无肿块型簇状钙化术中病理标本取材,定位准确,诊断明确,能确定乳腺微小病变的性质,提高乳腺癌的诊断率。 相似文献
998.
颅咽管瘤钙化与骨化关系的研究 总被引:1,自引:1,他引:0
目的 通过对颅咽管瘤超微结构的研究,病理学及影像学资料的复习,探讨颅咽管瘤骨化特点及其形成机制. 方法 收集南方医科大学南方医院神经外科自2004年5月至2006年3月手术的颅咽管瘤标本54例,其中男31例;女23例.术后病理证实为成釉细胞型颅咽管瘤41例,鳞状细胞型颅咽管瘤13例.分析肿瘤标本的显微结构、组织类型、骨化的特征.透射电镜分析颅咽管瘤骨化的超微结构基础,结合手术及影像学资料,分析颅咽管瘤骨化及其与钙化的关系. 结果 成釉细胞型颅咽管瘤钙化情况:7例(-),11例(+),11例(++),12例(++++);鳞状细胞型颅咽管瘤钙化情况:13例(-).镜下可见蛋壳样钙化及大块钙化的颅咽管瘤存在骨化,而在鳞状细胞型颅咽管瘤、无钙化及砂粒样钙化的成釉细胞型颅咽管瘤标本中未见骨化的现象;骨化结构的分布与钙化的程度密切相关. 结论 颅咽管瘤骨化的发生与钙化程度存在密切的联系,钙化是颅咽管瘤骨化的基础,骨化的形成使原本没有生物学活性的钙化结构变成含有肿瘤细胞、肿瘤间质的复合体,为术后残留的钙化组织导致肿瘤复发提供了基础. 相似文献
999.
目的总结高频超声诊断乳腺疾病的经验。方法回顾性分析54例经手术病理证实的乳腺肿块的高频超声资料并加以总结。结果 32例恶性肿块,微钙化30例,占93.75%;粗钙化2例,占6.25%。22例良性肿块,微钙化4例,占18.18%;粗钙化13例,占59.09%;弧形钙化5例,占22.73%。结论超声检查可有效识别乳腺病变内的微钙化,特别是恶性病变,其对乳腺病变的诊断与鉴别诊断具有重要临床应用价值。 相似文献
1000.
Hizukuri A Nakayama R Nakako N Kawanaka H Takase H Yamamoto K Tsuruoka S 《Journal of digital imaging》2012,25(3):377-386
In a computer-aided diagnosis (CADx) scheme for evaluating the likelihood of malignancy of clustered microcalcifications on mammograms, it is necessary to segment individual calcifications correctly. The purpose of this study was to develop a computerized segmentation method for individual calcifications with various sizes while maintaining their shapes in the CADx schemes. Our database consisted of 96 magnification mammograms with 96 clustered microcalcifications. In our proposed method, a mammogram image was decomposed into horizontal subimages, vertical subimages, and diagonal subimages for a second difference at scales 1 to 4 by using a filter bank. The enhanced subimages for nodular components (NCs) and the enhanced subimages for both nodular and linear components (NLCs) were obtained from analysis of a Hessian matrix composed of the pixel values in those subimages for the second difference at each scale. At each pixel, eight objective features were given by pixel values in the subimages for NCs at scales 1 to 4 and the subimages for NLCs at scales 1 to 4. An artificial neural network with the eight objective features was employed to enhance calcifications on magnification mammograms. Calcifications were finally segmented by applying a gray-level thresholding technique to the enhanced image for calcifications. With the proposed method, a sensitivity of calcifications within clustered microcalcifications and the number of false positives per image were 96.5% (603/625) and 1.69, respectively. The average shape accuracy for segmented calcifications was also 91.4%. The proposed method with high sensitivity of calcifications while maintaining their shapes would be useful in the CADx schemes. 相似文献