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排序方式: 共有2870条查询结果,搜索用时 234 毫秒
31.
J. R. Sewell M.B.B. Chir. M.R.C.P. B. Liyanage M.B.B.S. M.R.C.P. F.R.C.R. B. M. Ansell M.D. F.R.C.P. 《Skeletal radiology》1978,3(3):137-143
A retrospective study of the radiographs and clinical records of 39 children with dermatomyositis, followed up at a referral centre for a mean period of eight years, revealed calcinosis in 29 children (18 giris, 11 boys). Clinical presentation of calcinosis was unpredictable and variable, ranging from four months to 12 years after onset of disease. Subcutaneous calcilication, often associated with subsequent ulceration of overlying skin, was observed more frequently than calcinosis in intermuscular fascial planes (29:7). Subcutaneous calcinosis was demonstrated most commonly about the knees and elbows and in the fingers and toes. Intermuscular calcinosis affected the fascial planes around the quadriceps, deltoid, biceps, and the gastrocnemius/soleus muscles.Calcinosis, predominantly of the subcutaneous lesions, regressed spontaneously in eight of 11 children where this could be assessed over a one to four year period. This high rate of spontaneous resolution must complicate evaluation of the efficacy of proposed anti-calcinotic treatments in juvenile dermatomyositis.While no apparent relationship was established between subcutaneous calcinosis, which was present in all 29 of the affected patients, and disease activity or severity, all seven children with the additional, extensive, and classical intermuscular fascial plane calcification developed this complication early and had severe disease.These findings are discussed in relation to previous studies. 相似文献
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基底节钙化与急性偏瘫综合征的关系 总被引:5,自引:1,他引:5
目的 探讨基底节钙化(BGC)与小儿急性偏瘫综合征(AHS)发病的关系。方法 对34例AHS病例有关,临床资料进行回顾性分析、总结。结果 39.4%AHS患儿有BGC,其中79.8%发病前10d内有明确轻微头部外伤史。临床表现为不同程度的一侧急性偏瘫,部分有惊厥发作,但无意识障碍,颅内压增高不明显。CT扫描显示在一侧或双侧基底节区点或片状钙化,其附近存在类圆形点或片状低密度灶。结论 BGC与外伤后AHS的发生有一定关系,故对年龄小于3岁、外伤后近期有偏瘫或惊厥发作患儿,应注意有BGC的可能。 相似文献
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目的 观察不同浓度的膦甲酸钠 (PFA)对高磷诱导的牛主动脉血管平滑肌细胞钙沉积和骨钙素 (OC)表达的影响。方法 用不同磷浓度 (正常磷Pi1.5mmol·L-1、高磷Pi2 0mmol·L-1)及含不同浓度膦甲酸钠的培养液 ,体外培养牛主动脉平滑肌细胞 ,观察血管平滑肌细胞钙沉积及骨钙素表达。用甲ο 酚酞络合酮方法测定钙含量 ,BCA法测定蛋白含量。培养上清液中骨钙素浓度用放射免疫法测定 ,用蛋白含量标化钙含量、骨钙素的浓度 ,RT PCR观察骨钙素mR NA的表达。结果 ①高磷组较正常磷组平滑肌细胞钙沉积增加 :细胞培养 6d后 ,高磷组 (77 187± 11 6 92 )mg·g-1Pro ,正常磷组 (2 5 76 8± 1 75 0 )mg·g-1Pro ,P <0 0 1;②膦甲酸钠能有效地抑制钙沉积 :培养 6d ,高磷 +PFA 1 0mmol·L-1组 (37 72 9± 5 899)mg·g-1Pro ,与高磷未干预组相比 ,P <0 0 1;③高磷组骨钙素表达明显增高。高磷组与正常磷组相比 ,培养上清液中骨钙素水平 :(1 5 0 3× 10 -2 ±2 6 0 1× 10 -3 )mg·g-1Pro对 (2 981× 10 -3 ± 8 382× 10 -4)mg·g-1Pro ,P <0 0 1;平滑肌细胞骨钙素mRNA表达 (OC/GAPDH) :1 886± 0 16 5对 0 75 2± 0 0 5 2 1,P <0 0 1;④膦甲酸钠能有效地抑制骨钙素的表达。高磷 +PFA 1 0mmol·L-1组与高磷组? 相似文献
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小儿腔隙性脑梗死的病因与CT分析 总被引:2,自引:0,他引:2
袁向东 《中国医师进修杂志》2006,29(3):30-31
目的探讨小儿腔隙性脑梗死的病因与CT表现。方法对43例腔隙性脑梗死的临床资料进行分析。结果(1)病因:头轻微外伤21例,上呼吸道感染8例,水痘2例,线粒体脑肌病(MELAS),烟雾病1例,系统性红斑狼疮1例,原因不明9例。(2)临床表现:偏瘫41例,失语5例,癫疒间10例,突发性耳聋2例。(3)CT:43例患儿发现51处病灶,其中15例患儿发现一侧或双侧基底节区点状或片状钙化,其附近存在类圆形点或片状低密度灶。(4)预后:40例患儿在12周内症状消失。结论小儿与成人引起腔隙性脑梗死病因不同,预后好。基底节钙化与外伤后急性偏瘫的发生有一定关系。 相似文献
36.
ObjectiveThe prognostic value of MAC severity is important not only because it shares a common risk factors with vascular atherosclerotic changes but also through increasing the cardiovascular morbidity and mortality. This study was conducted in order to evaluate association between severity of MAC and left sided echocardiographic abnormalities mainly left sided valvular abnormalities as well as left atrial systolic and diastolic functional abnormalities.MethodsWe prospectively obtained 12-leads electrocardiograms and transthoracic echocardiograms (TTE) on patients scheduled for non-emergent echocardiographic assessment at tertiary care hospital. MAC was graded as mild, moderate and severe. LA linear dimensions, LA filling and emptying volumes and left atrium ejection fraction were done specifically in addition to commonly measured TTE parameters.ResultsFrom the 80 patients considered for the study, 47 patients had mild MAC, 29 patients had moderate MAC and 4 patients had severe MAC. Valvular affection through echo-doppler assessment that included mainly mitral stenosis, mitral incompetence, aortic sclerosis as well as aortic incompetence showed a highly significant statistical difference (p-values 0.00, 0.00, 0.00 and 0.00 respectively). There was a highly significant statistical difference between patients with different degrees of MAC and LA linear dimension (p-value 0.00), all LA filling and emptying volumes as well as LA ejection fractions with the exception of LA passive emptying volume and LA passive ejection fraction was insignificant.ConclusionsThere is a direct proportionate relationship between severity of MAC and associated left sided valvular affection, increase LA linear dimension as well as lower overall LA function. 相似文献
37.
《Connective tissue research》2013,54(1-3):185-192
To investigate the mechanism of biological calcification in vitro a model system consisting of an acrylamide gel block (1×3×3 mm) and fetal bovine serum was developed. Mineral deposition was induced in gel blocks which were immersed in 300 μl of fetal bovine serum at 37°C for 7 days in a CO2 incubator. X-ray diffraction indicated that the mineral was hydroxyapatite with low crystallinity. Effects of the concentration of acrylamide gel, the partial pressure of CO2 and matrix proteins within the gel on the mineral formation were investigated. In the gel concentration range of 10–60%, the largest amount of crystal grew in 40% acrylamide gel, where the serum protein did not penetrate. With an increase in the partial pressure of CO2 the Ca content in the gel block increased, reached the highest level at about 3.5% CO2 and then began to decrease. In 40% gel and at 5% CO2 the mineral formation was enhanced by phosvitin, phosphophoryn, demineralized dentin powder and alkaline phosphatase. Mineral deposition occurred around the collagen fibers immobilized in 40% acrylamide gel. These results indicate that 1) a putatively serum-derived inhibitor of calcification with high-molecular weight was prevented from penetrating into the 40% acrylamide gels, 2) immobilized polyanionic proteins and alkaline phosphatase were able to increase mineral deposition and 3) the partial pressure of CO2 greatly influenced the mineral deposition. It was concluded that this gel system is useful to investigate the mechanism of biological calcification in vitro. 相似文献
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