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51.
目的探讨超声造影在伴有钙化的甲状腺结节诊断中的临床价值。方法对73例甲状腺良性结节和53例甲状腺恶性结节患者分别进二维超声和超声造影检查,比较良恶性结节微钙化、弱增强及不均匀增强的构成比,并比较超声造影时良恶性结节始增时间、达峰时间和峰值强度。结果伴有钙化的甲状腺恶性结节微钙化、弱增强及不均匀增强的构成比均高于良性结节(P0.05);超声造影恶性结节峰值强度低于良性结节(P0.05),良恶性结节始增时间、达峰时间差异无统计学意义(P0.05);超声造影对伴有钙化甲状腺结节良恶性诊断的敏感度、特异度、阳性预测值及阴性预测值均高于二维超声检查(P0.05)。结论超声造影可敏感、动态地观察甲状腺结节的增强特点,对伴有钙化的甲状腺结节的诊断具有较高的临床价值。 相似文献
52.
老年钙化瓣膜病的研究新进展 总被引:2,自引:0,他引:2
老年钙化瓣膜病可引起心脏瓣膜的狭窄和关闭不全,临床上以主动脉瓣和二尖瓣及其瓣环最常受累。它是引起老年人充血性心力衰竭、心律失常、晕厥和猝死的重要原因之一,也是老年人最常见的心脏瓣膜病变。该文就老年钙化瓣膜病的发病机制、危险因素等方面予以综述,从探讨中寻找治疗的新进展,如他汀类药物、肾素-血管紧张素系统抑制药物及抗骨质疏松药物的应用,并对经皮主动脉瓣膜置换术的新进展进行相关阐述。 相似文献
53.
目的 通过研究环氧氯丙烷(ECH)处理对瓣膜组织结构及表面性状的影响,探究ECH处理生物瓣膜后防钙化的机制。方法 通过测定ECH处理瓣膜组织的抗酶消化能力、茚三酮值、热皱缩温度,以及血浆蛋白吸附实验、血小板黏附实验评价ECH处理瓣膜组织的表面性状。结果 经ECH处理后,抗酶消化能力增加,茚三酮值下降,热皱缩温度升高(P〈0.01),且对血浆蛋白和血小板的黏附减少,表面性状改善。结论 ECH处理能够增加瓣膜组织的交联,且改善瓣膜的表面性状,是ECH处理瓣膜组织防钙化、防衰坏的机制之一。 相似文献
54.
Mauro Alini Yasumoto Matsui George R. Dodge A. Robin Poole 《Calcified tissue international》1992,50(4):327-335
Summary Calcification occurs in the extracellular matrix of the hypertrophic zone of the growth plate when the extra-cellular matrix volume is reduced to a minimum and alkaline phosphatase content is maximal. The present study shows that significant quantitative and qualitative changes occur in the composition and structure of macromolecules in the extracellular matrix before and during calcification in the proximal tibial growth plate of the bovine fetus. These were detected in part by using microchemical and microimmuno-chemical analyses of sequential transverse frozen sections at chemical analyses of sequential transverse frozen sections at defined sites throughout the growth plate. Concentrations of matrix molecules in the extracellular matrix have not previously been determined biochemically. They were measured per unit matrix volume by using combined immunochemical/chemical-histomorphometric analyses. The concentrations within the extracellular matrix of the C-propeptide of type II collagen, aggregating proteoglycan (aggrecan), and hyaluronic acid all progressively increased in the maturing and hypertrophic zones, being maximal (or near maximal) at the time of initiation of mineralization. These results for proteoglycan are contrary to some earlier reports of a loss of proteoglycan prior to mineralization which measured the tissue content of proteoglycan rather than that present in the extracellular matrix, the volume of which is progressively reduced as the growth plate matures. The C-propeptide data provides a quantitative confirmation of previous immunohistochemical studies. Total collagen concentration (measured as hydroxyproline) in the extracellular matrix initially increased through the proliferating and maturing zones but then rapidly decreased in the hypertrophic zone. Immunohistochemical studies revealed that this is associated with the unwinding of the triple helix of type II collagen (previously shown to result from cleavage) which starts in pericellular sites in the zone of maturation (when type X collagen is first synthesized) and then extends throughout the hypertrophic zone. The significance of these matrix changes in the development and mineralization of the growth plate is discussed. 相似文献
55.
56.
目的探讨钙化在非肿块型乳腺肿瘤X线诊断中的意义,提高对非肿块型乳腺良、恶性肿瘤的鉴别诊断水平。方法回顾性分析2008年11月至2011年3月期间四川大学华西医院经病理检查证实的X线片未见肿块的90例乳腺肿瘤患者的临床资料,其中乳腺良性肿瘤55例,乳腺癌35例,观察并记录钙化的形态、分布、总数、位置及乳腺局限性不对称致密。结果①乳腺良性疾病钙化形态多粗大(31例),多以散在分布为主(35例),且钙化总数较少,较少伴有乳腺局限性不对称致密影(7例),较少伴有同侧腋窝淋巴结的改变(2例)。②乳腺癌的钙化多以细砂样钙化为主(32例),颗粒细小,但钙化大小不一致,形态各异,其钙化的分布多呈簇样分布(24例),且恶性钙化的总数较多,多伴有乳腺局限性不对称致密影(24例),伴有腋窝淋巴结改变(10例)。两者钙化的形态、分布及总数的差异均有统计学意义(P<0.05)。结论良、恶性乳腺肿瘤的钙化各有特征,在早期乳腺肿瘤的鉴别诊断中有着重要的临床意义。 相似文献
57.
Kazuto Yamazaki MD Shoichi Ichimura Terence D Allen Tomoyuki Nakagawa 《Journal of bone and mineral metabolism》1989,7(3):6-17
Summary To analyze the mechanism of initiation of cell-mediated calcification in hard tussue and its relationship to the frequency
of gap junctions, enzymatically isolated cells from fetal rat calvaria cultured in collagen gels were observed ultrastructurally
over a time course. Calcification was observed at 2–3 weeks after the initiation of culture when the seeding cellularity and
the concentration of β-glycerophosphate were sufficiently high. In the collagen gels, round cells (R), spindle or stellate
cells (S), and fat cells (F) were characterised morphologically. The ultrastructural features of initial calcification could
be classified into 4 subtypes: 1) a large mass greater than 10 μm in diameter (Type I), 2) deposition associated with dead
R cells or matrix vesicles (Type II), 3) intracellular deposition (Type III), and 4) other than Types I–III (Type IV). Type
II was the most frequent (44.5%) and Type III was the least (6.8%). Gap junction was observed frequently between 1) R cells,
2) S cells, 3) between R cells and S cells. The frequency of gap junctions in collagen gels decreased statistically (X2-test; p<0.001), when calcification was initiated. This cell culture system can be regarded as a useful model to analyze the
initiation of cell mediated calcification in hard tissue. Gap junctions might function in cell communication and a decrease
in their numbers could lead to cell death and, subsequently to calcification. 相似文献
58.
59.
The first case of a ventrally exophytic pontine glioma with extensive and dense calcification is reported. A 10-year-old boy
presented with a generalized seizure. The skull radiogram and CT scan showed a dense area of calcification, revealed by MRI
as the core of a ventrally exophytic tumor. The pathologic diagnosis was fibrillary astrocytoma. 相似文献
60.
钼靶X线对乳腺浸润性导管癌与导管内癌钙化灶的研究 总被引:4,自引:0,他引:4
目的:探讨浸润性导管癌与导管内癌钙化的钼靶X线表现特点。方法:回顾性分析行乳腺钼靶X线检查并经手术及病理证实的135例乳腺浸润性导管癌患者与17例导管内癌患者。结果:135例浸润性导管癌患者中,72例(53.3%)可见钙化,其中钙化伴有肿块者63例(46.7%),钙化不伴肿块表现者9例(6.7%)。17例乳腺导管内癌中,14例(82.4%)可见钙化,钙化伴有肿块者3例(17.7%),钙化不伴肿块表现者11例(64.7%)。导管内癌钙化的发生率显著大于浸润性导管癌,浸润性导管癌钙化伴有肿块的发生率显著大于导管内癌。结论:仔细分析乳腺的钙化灶,对浸润性导管癌与导管内癌的诊断有一定的价值。 相似文献