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51.
甲状腺术后瘢痕组织是甲状腺局部分切除术后由于手术方式及缝线填充而形成的组织,甲状腺术后瘢痕组织形成及其发生发展过程同一般的组织损伤修复病理过程一样,为渐进老化阶段的结缔组织,其内小血管稀少,胶原纤维增多[1]。由于甲状腺术后瘢痕组织其质地较硬,活动性差,超声声像图上表现缺乏典型特征,与癌灶极其相似,因此鉴别较困难。本文将介绍超声对于甲状腺术后的随诊应用,分析甲状腺术后瘢痕组织的超声检查特点并着重介绍超声动态观察甲状腺术后瘢痕组织的应用及其发展前景。 相似文献
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B. Lundin M. L. Manco‐Johnson D. M. Ignas R. Moineddin V. S. Blanchette A. L. Dunn S. V. Gibikote S. N. Keshava R. Ljung M. J. Manco‐Johnson S. F. Miller G. E. Rivard A. S. Doria The International Prophylaxis Study Group 《Haemophilia》2012,18(6):962-970
Evaluation of prophylactic treatment of haemophilia requires sensitive methods. To design and test a new magnetic resonance imaging (MRI) scale for haemophilic arthropathy, two scales of a combined MRI scoring scheme were merged into a single scale which includes soft tissue and osteochondral subscores. Sixty‐one joint MRI's of 46 patients with haemophilia were evaluated by four radiologists using the new and older scales. Forty‐six of the joints were evaluated using two X‐ray scales. For all MRI scores, interreader agreement and correlations with X‐ray scores and lifetime number of haemarthroses were analysed. The interreader agreement intraclass correlation coefficient was 0.82, 0.89 and 0.88 for the soft tissue and osteochondral subscores and the total score, as evaluated according to the new MRI scale, compared to 0.80 and 0.89 as for the older scales. The total score and osteochondral subscore according to the new scale, as well as scores according to the older scales were correlated (P < 0.01) with number of haemarthroses (Spearman correlation 0.35–0.68) and with the X‐ray scores (Spearman correlation 0.40–0.76), but no correlation (P > 0.05) was found between the soft tissue subscore of the new MRI scale and the X‐ray scores. The new MRI scale is simpler to apply than the older and has similar reader reliability and correlation with lifetime number of haemarthroses, and by separating soft tissue and osteochondral changes it gives additional information. The new scale is useful for analyses of early and moderate stages of arthropathy, and may help to evaluate prophylactic haemophilia treatment. 相似文献
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Introduction
Postural dysfunction is one of the major features of idiopathic normal pressure hydrocephalus (iNPH). With computerized dynamic posturography (CDP) balance can be assessed objectively. The primary aim of this study was to describe the postural function in iNPH patients pre- and post-operatively in comparison with healthy individuals (HI) using CDP.Subjects and methods
Thirty-five patients (16 M, 19 F) with a mean age of 73 (range 49–81) with iNPH, and sixteen HI (7 M, 9 F) aged 73 (62–89) were included. iNPH patients were operated on with a ventriculo-peritoneal shunt. Patients and HI were tested regarding motor function, balance and cognition. CDP, EquiTest (NeuroCom International, Clackamas, OR), was performed before and three months after shunt surgery and twice in HI, with a three-month interval.Results
Pre-operatively, the 35 patients had poorer balance measured with the Sensory Organizing Test (SOT) score in every condition (p = 0.01 in SOT 1 and p < 0.001 in SOT 2–6) compared to the HI. The greatest difference was in test conditions measuring mainly vestibular function, where loss of balance (LOB) was frequent. Twenty patients were evaluated three months after shunt surgery and 18/20 (90%) of them were considered shunt responders, with a mean improvement of motor score of 26% (range 5–67%). There was an improvement post-operatively in the weighted composite SOT score (p < 0.05) but no significant change in any of the SOT conditions. LOB was not significantly reduced in any of the test conditions.Conclusion
CDP showed that the patients had a poorer balance than the HI. The greatest difference was in SOT 5–6, indicating that the postural disturbance is of primarily central vestibular origin. There was a slight improvement of balance post-operatively. 相似文献58.
摘要:目的 探讨白花蛇舌草-半枝莲药对组分对结肠腺癌Lovo细胞增殖、侵袭、迁移和凋亡的影响及作用机制。方法 将白花蛇舌草、半枝莲按质量1∶1进行3次煎煮,获得水提物,后取适量浸膏用石油醚回流脱脂,再以乙酸乙酯进行多次萃取,获得白花蛇舌草-半枝莲药对组分,并计算得率。实验分为对照组(正常培养Lovo细胞)、白花蛇舌草-半枝莲药对组分低剂量组(10 mg/L)、中剂量组(30 mg/L)及高剂量组(50 mg/L)。通过噻唑蓝比色法(MTT)检测各组细胞培养24、48、72 h后的增殖抑制率。各组细胞培养48 h后,流式细胞仪检测细胞周期分布;Transwell实验检测细胞侵袭能力;划痕实验检测细胞迁移能力;TUNEL法检测细胞凋亡情况;Western blot法检测Grb2相关结合蛋白1(Gab1)、血管内皮生长因子受体2(VEGFR-2)、磷脂酰肌醇3-激酶(PI3K)、苏氨酸激酶(Akt)、基质金属蛋白酶-9(MMP-9)、B淋巴细胞瘤-2基因(Bcl-2)、Bcl-2相关X蛋白(Bax)蛋白表达情况。结果 化学萃取后的白花蛇舌草-半枝莲药对中主要含有对羟基苯乙酮、野黄芩苷、木犀草素和芹菜素4种化合物,组分得率为0.61%。与对照组相比,低、中、高剂量组细胞增殖抑制率升高,G1期肿瘤细胞比例增加,细胞凋亡指数增高,侵袭细胞数和划痕闭合率明显减小(均P<0.05),细胞中Gab1、VEGFR-2、PI3K、Akt、MMP-9、Bcl-2蛋白表达降低,Bax表达升高(均P<0.05),且存在剂量依赖性。结论 白花蛇舌草-半枝莲药对组分可抑制结肠腺癌Lovo细胞的增殖,降低其迁移和侵袭能力,诱导细胞凋亡,其机制可能与抑制Gab1/VEGFR-2/PI3K/Akt信号通路活化有关。 相似文献
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Pneumothoraces are a possible sequela of chest trauma with potential morbidity and mortality if not recognized and treated promptly. A portable supine chest radiograph is frequently the first radiologic study performed in the setting of trauma. While large pneumothoraces can be readily recognized on these radiographs, smaller pneumothoraces are missed in up to 15 % of trauma patients. There are many radiographic signs of occult pneumothoraces, and we are presenting a new radiographic sign of occult pneumothorax. The floating cardiac fat pad sign occurs when pleural air collects anteriorly and superiorly in the most non-dependent portion of the chest lifting the pericardial fat pad off the diaphragm. Lung markings are still seen surrounding the pericardial fat pad due to the inflated lower lobe of the lung resting dependently. Rapid and accurate identification of pneumothoraces is critical but often difficult on chest radiographs. Although there are many existing radiographic signs for identification of pneumothorax, prospective identification of small pneumothoraces is still relatively poor. Here, we describe an additional sign which aides in the detection of pneumothoraces, the floating cardiac fat pad. When present, this should prompt further evaluation with chest CT or upright chest radiograph. 相似文献