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61.
目的探讨黄芪注射液抗肝纤维化及对TGF-β1、Col-Ⅰ表达的影响。方法将35只SD大鼠随机分为正常对照组、CCl4诱导肝纤维化模型组和黄芪干预组。至造模第10周,处死所有大鼠,采用PV免疫组化方法检测Col-Ⅰ在各组肝组织中的表达,ELISA法检测TGF-β1在各组血清中的表达。结果经CCl4诱导成功建立大鼠肝纤维化模型,随着肝纤维化程度的进展,肝组织中Col-Ⅰ和血清中TGF-β1表达明显增强。在正常对照组、黄芪干预组和肝纤维化模型组肝组织中Col-Ⅰ表达的平均光密度值分别为0.298、0.315、0.503,模型组与前两组比较差异均有显著性(P〈0.01),而黄芪干预组与正常组肝组织比较差异无统计学意义(P〉0.05)。在正常对照组、黄芪干预组和肝纤维化模型组大鼠血清中TGF-β1表达含量分别为491.29pg/L、629.91pg/L、959.09pg/L,呈递增趋势。模型组与前两组比较差异均有显著性(P〈0.01),黄芪干预组与正常组比较其表达含量无显著差异(P〉0.05)。结论黄芪注射液可以显著抑制实验性肝纤维化大鼠模型的肝纤维化,这种抑制作用可能与抑制I型胶原蛋白及TGF-β1的表达有关。 相似文献
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63.
Intracranial abnormalities in infants treated with extracorporeal membrane oxygenation: imaging with US and CT 总被引:1,自引:0,他引:1
Findings at neuroimaging in 100 consecutive infants treated with extracorporeal membrane oxygenation (ECMO) are presented. Imaging in these infants consisted of pretreatment cranial ultrasonography (US), daily US studies while on ECMO, and follow-up cranial computed tomography (CT) after treatment. There were findings of abnormalities in 43 patients. Thirty had intracranial bleeding, often of unusual extent and distribution. Thirteen additional infants had nonhemorrhagic abnormalities alone. Bleeding considered to be major was seen in 12% of infants. Large parenchymal hemorrhages and infarcts, cerebellar hemorrhages, and diffuse edema were the most significant abnormalities, with a 50% mortality (eight of 16 patients). No lateralization was noted with respect to distribution of bleeding sites or areas of nonhemorrhagic abnormalities. US was a sensitive but imperfect screening tool for intracranial abnormalities. Abnormalities missed with US included peripheral and small parenchymal lesions, subarachnoid hemorrhage, cerebral atrophy, and sagittal sinus thrombosis. 相似文献
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66.
Peptic ulcer and gastric carcinoma: diagnosis with biphasic radiography compared with fiberoptic endoscopy 总被引:1,自引:0,他引:1
Shaw PC; van Romunde LK; Griffioen G; Janssens AR; Kreuning J; Eilers GA 《Radiology》1987,163(1):39-42
The diagnostic value of biphasic radiographic examination of the stomach and duodenum was compared with that of fiberoptic endoscopy in a prospective, blinded study of 385 patients with dyspepsia. This investigation was directed at gastric malignancies and peptic ulcers. Methodologically there is no absolute standard for a study of this kind because histologic examination is useful for detection of cancer but inadequate for ulcers. As an alternative, kappa indexes and the sensitivity and specificity, as derived by Hui and Walter, were calculated and compared. For the detection of gastric carcinoma, radiographic and endoscopic findings had almost perfect agreement beyond chance. For gastric ulcers, radiography and endoscopy had substantial agreement, which became perfect if small ulcers (less than 5 mm) were excluded. For duodenal ulcers, radiography had a lower sensitivity than endoscopy; this disagreement disappeared if small ulcers were excluded. Both methods have equal merit; choice of the initial diagnostic procedure will therefore depend on cost, discomfort to the patient, and risk of complications. 相似文献
67.
Parathyroid scintigraphy using a double-tracer (T1-201, Tc-99m) subtraction technique depicted 17 of 23 (74%) parathyroid adenomas in patients with and without previous neck operations. High-resolution (10-MHz) ultrasound (US) depicted 18 (78%) of these adenomas. Average tumor size depicted by US was 17 X 10 X 8 mm (excluding a giant adenoma) and 19 X 10 X 9 mm by scintigraphy. Alone, neither modality was particularly sensitive in the depiction of primary hyperplasia of the parathyroid glands, but combined techniques were more effective than the use of a single modality. With both US and T1-201 scintigraphy, only two of 23 cases of parathyroid adenoma in the neck were missed, and none of the eight cases of secondary hyperplasia were missed. In 11 patients who had previously undergone neck surgery, parathyroid tumors were identified in eight by either US or double-tracer scintigraphy. Preoperative parathyroid imaging with double-tracer scintigraphy and high-resolution US is suggested for patients with hyperparathyroidism, particularly in those patients who have had previous parathyroid surgery. 相似文献
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69.
Daniels DL; Czervionke LF; Millen SJ; Haberkamp TJ; Meyer GA; Hendrix LE; Mark LP; Williams AL; Haughton VM 《Radiology》1989,171(3):807-809
The authors evaluated magnetic resonance (MR) images obtained with intravenously administered gadolinium in ten patients who had facial paralysis and no facial nerve tumor. In patients with either Bell palsy (four patients) or facial paralysis after temporal bone surgery (six patients), intratemporal facial nerve enhancement was seen. Facial nerve enhancement on MR images proved to be a nonspecific finding. 相似文献
70.
PLS—紫外分光光度法同时测定复方阿斯匹林片中三组分含量 总被引:7,自引:0,他引:7
本文研究了复方阿斯匹林片中阿斯匹林、非那西丁和咖啡因含量同时测定的紫外分光光度法的最佳实验条件,并简述偏最小二乘法(PLS)在多组分同时测定中的基本原理和应用。三组分模拟试样回收率平均值的置信区间分别为100.1±0.23%,100.0±0.25%和100.1±0.33%(置信度95%)。PLS法是一种理想的多组分测定方法,计算速度较快,结果更准确可靠,尤其适用于成批试样的分析,为微机控制的紫外可见分光光度计提供了一种新方法。 相似文献