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91.
92.
Intramuscular haemangiomas are benign soft tissue tumours that are more frequently seen in children and young adults. As they may be difficult to diagnose clinically, imaging has an important role in the detection, diagnosis and preoperative planning of these lesions. Haemangiomas of the extremities may be classified into capillary, cavernous, venous and mixed types, with or without an arteriovenous shunt, depending on the predominant vascular channels. Nonvascular components such as fat, smooth muscle, fibrous tissue and thrombus may also be present. This pictorial essay highlights the imaging features of intramuscular haemangiomas, with an emphasis on magnetic resonance imaging.  相似文献   
93.
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Nonobstructive Dysphagia in Reflux Esophagitis   总被引:2,自引:0,他引:2  
Dysphagia in the absence of organic esophageal stricture may occur in patients with reflux esophagitis. Although the exact mechanism of this "nonobstructive dysphagia" (NOD) is not known, it is believed to be related to transient segmental esophageal motor disorder. The goals of this study were to determine the frequency of NOD in patients with reflux esophagitis and correlate it with esophageal pH and motility changes. Sixty-three consecutive patients with symptoms of esophageal dysfunction were studied with endoscopy, infusion esophageal manometry, and 24-h ambulatory esophageal pH monitoring. Forty-seven had severe erosive esophagitis unresponsive to medical therapy; 16 with esophageal motility disorders were used as symptomatic controls. Twenty-eight of 63 patients studied experienced NOD during the 24-h pH study; 22 had esophagitis and six had esophageal dysmotility without esophagitis. NOD was noted with similar frequency in the two groups; 22/47 (46.8%) of patients with esophagitis and 6/16 (37.5%) with esophageal dysmotility experienced NOD during the period of study. NOD correlated with pH less than 4.0 in 88.6% of patients with esophagitis but in only 7% of patients with esophageal dysmotility (p less than 0.001). There was no difference in acid reflux patterns in esophagitis patients who experienced NOD (22/47), and in those who did not (25/47). There was no correlation between NOD and baseline esophageal motility abnormalities. In summary, 1) NOD is a common, intermittent symptom that occurred in up to 46.8% of esophagitis patients and 37.5% of symptomatic controls during the 24-h period of this study; 2) NOD correlates with esophageal pH less than 4.0 in patients with esophagitis and not in patients with esophageal dysmotility. These data strongly suggest that acid in the distal esophagus frequently triggers the sensation of dysphagia in esophagitis patients, but not in patients with esophageal motility disorders. Combined ambulatory intraesophageal motility and pH monitoring may further elucidate the mechanism of dysphagia in these patients.  相似文献   
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The change in transfer coefficient (Kco) with increasing heart rate during exercise was studied in 25 normal subjects and in 21 patients with pulmonary sarcoidosis. The slope of the Kco response against heart rate was found to be 0·0053 mmol min−1 kPa−1 l−1 per beat in the normal group but in many of the patients was two standard deviations or more below this normal slope, even when their routine function tests were normal. This response of Kco to exercise is a more sensitive index of changed function than more routine function tests in pulmonary sarcoidosis.  相似文献   
97.
Giant cell tumour of the tendon sheath is a soft tissue mass found occasionally in the hand. Its diagnosis can be readily made preoperatively if the characteristic MRI features are appreciated. This pictorial essay demonstrates and describes the imaging findings correlated with histopathological findings in a group of patients with proven giant cell tumour of the tendon sheath.  相似文献   
98.
Cervical spine trauma accounts for majority of spinal injuries, and approximately one‐third involve the craniocervical junction (CCJ). Due to its high sensitivity, magnetic resonance imaging (MRI) has become the standard tool for imaging suspected ligamentous injuries in an unstable spine and in patients with neurological deficits having a normal CT. The ligamentous anatomy of the CCJ is complex, and thorough knowledge is a prerequisite for accurate interpretation of the MRI findings. This pictorial essay aims to familiarise radiologists with the ligamentous anatomy, mechanisms of injury and MRI appearances of injuries in the cervical spine, with emphasis on the CCJ.  相似文献   
99.
目的:观察承载丸含药血清对甲基强的松龙预处理的MC3T3-E1成骨细胞L-钙通道电流的影响。方法:实验于2006-04/06在中国中医科学院望京医院药理实验室及吉林大学基础医学院生理教研室完成。①实验材料:MC3T3-E1(购于北京协和细胞中心);8个月龄SD大鼠10只,雌雄各半;中药制剂承载丸(由鹿角霜、肉苁蓉、续断、黄芪、当归、炙水蛭、杜仲、蛋衣、皂角刺、香附、乌药等21味中药组成);甲基强的松龙(批号H20040338,Pharmacia NV/SA生产)。②实验干预:成骨细胞(MC3T3-E1)传代培养。承载丸药粉60g,加水至200mL搅匀,取大鼠6只(雌雄各半),每只灌服2.5mL/d,灌服4d后动脉取血,制备含药血清。另取大鼠4只,同法灌服生理盐水,制成不含药血清。甲基强的松龙的浓度为1×10-5mol/L。③实验分组:将培养后的成骨细胞株分为4组:正常组(加入正常大鼠不含药血清)、模型组(加入正常大鼠不含药血清及甲基强的松龙)、承载丸低剂量组(加入甲基强的松龙及0.5mL承载丸含药血清)和承载丸高剂量组(加入甲基强的松龙及0.1mL承载丸含药血清)。④实验评估:24h后,用全细胞膜片钳技术记录每组10个细胞的L-钙通道电流,并测定其峰值电流。结果:①各组电流峰值测定结果:模型组峰值电流比正常组下降19.5%[(0.1839±0.0179),(0.2284±0.0209)nA,P<0.01];承载丸低剂量组和高剂量组比模型组分别升高37.4%和45.2%[(0.2526±0.0093),(0.2671±0.0120),(0.1839±0.0179)nA,P<0.01];承载丸高低剂量组相比差异有显著性意义(P<0.05)。②MG3T3E1细胞钙电流的特性分析:正常组,钙通道大约在-20mV时开放,最大峰值电流在 20~ 30mV,反转电位在 60~ 70mV。当在浴液中加入Co2 ,可阻断此电流的大部分电流成份,其峰值电流为(0.1050±0.0097)nA,而钙离子激活剂Bayk8644增加了此电流(0.3335±0.0323)nA。结论:①甲基强的松龙抑制成骨细胞L-钙通道电流。②承载丸含药血清可升高甲基强的松龙预处理的成骨细胞L-钙通道电流。  相似文献   
100.
目的:文章就骨髓间充质干细胞治疗脑梗死的应用研究进展及其治疗作用机制进行综述。资料来源:应用汁算机检索Medline1999-01/2006-11骨髓间充质干细胞相关细胞修复的文献,检索词"mesenchymal stemcells,cerebral ischemia,stroke"并限定文献语言种类为English。资料选择:对资料进行初审,选择包含骨髓间充质干细胞治疗脑缺血的基础研究文章,排除重复研究、综述类文献。资料提炼:纳人35篇符合标准的文献,对骨髓间质干细胞在脑梗死中的应用及其修复机制进行归纳。资料综合:①骨髓间充质干细胞具有高度的自我复制能力和多向分化潜能,可分化成多种细胞。骨髓间充质干细胞移植是近年来医学领域的研究热点,被用于脑梗死动物模型的治疗。②骨髓间充质干细胞对脑梗死动物模型具有较好的治疗作用。③骨髓间充质干细胞能够激活内源性的修复机制。④骨髓间充质干细胞移植后能够分泌大量营养因子从而发挥其神经保护和营养支持作用。结论:骨髓间充质干细胞对脑梗死具有较好的治疗作用,主要通过其移植后分泌大量营养因子从而发挥对脑梗死的治疗作用。  相似文献   
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