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991.
992.
Carrageenin pleurisy was induced in adrenalectomised (ADX) and sham-operated (SHO) rats. The magnitude and duration of inflammation, as estimated by fluid exudation and cell migration, was greatly increased (approximately doubled) in ADX rats compared with that in their SHO controls. The content of eicosanoids (6-keto-prostaglandin F1 alpha (6-keto-PGF 1 alpha), thromboxane B2 (TXB2), and leukotriene B4 (LTB4] in inflammatory exudates from ADX rats was significantly (2-4 fold) greater than that of their SHO controls. Resident macrophages obtained from ADX rats produced more eicosanoids per cell per unit time when stimulated in vitro with zymosan, than did cells from the SHO controls. Administration of glucocorticoids blocked the inflammatory response and reduced the release of eicosanoids both in vitro and in vivo in both groups of rats. These data are consistent with the notion that physiological amounts of glucocorticoids exert a tonic inhibitory action on phospholipase activity in normal animals and that the increased secretion of these hormones during the inflammatory response serves to check and control the development of inflammation.  相似文献   
993.
To study the pathological and histochemical characteristics of lesions in piglet livers infected with Taenia saginata asiatica (T. saginata asiatica) throughout the different stages, piglets were fed with eggs of T. saginata asiatica and raised in isolation in an animal center to establish the T. saginata asiatica infection model with normal piglets as control. The pathological changes in the piglet livers were observed after the infection using liver sections stained with hematoxylin and eosin. Histochemical methods were used to check the changes in lipid, glycogen and protein content in the liver. The data collected by image analysis were analyzed statistically with Statistical Package for the Social Science. The results show that T. saginata asiatica-exposed piglets were indeed infected. Inflammatory reactions began on the fourth day and progressed rapidly. Kupffer cell hyperplasia, hepatic hydropic degeneration and ballooning degeneration were found in the 10th–20th days after infection. Hepatic central veins and hepatic sinusoids were dilated and congested. Spotty necrosis occurred in some local liver tissues. In the 40th–60th days, granulomatous reactions and mild hepatocirrhosis were the main lesions. In the 70th–80th days, hepatocirrhosis and bile duct proliferation were observed in the liver. In the different stages, lipid drops were increased while glycogen and protein levels were decreased to some degree. There was a significant difference in metabolism between the infected group and the control group (P < 0.01). It is concluded that pigs are the favorable intermediate host of T. saginata asiatica and its infection can result in serious pathological and histochemical lesions in host organs. Translated from Journal of Guiyang Medical College, 2006, 31(4): 296–300 [译自: 贵阳医学院学报]  相似文献   
994.
CT血管成像对肝细胞癌合并肝动脉-门静脉分流的诊断价值   总被引:4,自引:0,他引:4  
目的探讨CT血管成像(CTA)对肝细胞癌(HCC)合并肝动脉-门静脉分流(APS)的诊断价值。方法127例HCC患者分别接受肝脏多层螺旋CT动态增强扫描和DSA检查,间隔时间3-15d。所有患者进行CTA检查,并以DSA为标准,对照分析CT动态增强扫描基础上进行CTA成像对APS的诊断价值。结果DSA证实52例(40.94%)HCC患者合并APS,中央型33例,周围型19例。CT横断面与横断面基础上结合CTA诊断APS的敏感度均为94.23%(49/52),特异度分别为84.00%(63/75)和97.33%(73/75),正确率分别为88.19%(112/127)和96.06%(122/127),阳性预测值分别为80.33%(49/61)和96.08%(49/51),阴性预测值分别为95.45%(63/66)和96.05%(73/76)。CTA排除了横断面CT对4例中央型APS和6例周围型APS的假阳性诊断。与DSA比较,多层螺旋CT对APS的分型符合率达88.46%(46/52),其中,中央型90.91%(30/33),周围型84.21%(16/19)。CTA还直观地显示23例重度分流中央型APS的供血动脉,其中19例为肝固有动脉分支,4例为胃十二指肠动脉分支。结论在多层螺旋CT动态增强扫描基础上进行CTA成像,能有效提高APS诊断的特异度和正确率。  相似文献   
995.
Immediate chairside replacement of an extracted anterior tooth may contribute to a patient's comfort, treatment acceptance, and expectations of treatment; however, fabrication of a custom restoration in the anterior region of the mouth may result in an esthetic compromise for patients during the fabrication period. Chairside tooth replacement is an excellent application of fiber-reinforced composite resin technology. This article presents an innovative, affordable chairside procedure in which Ribbond Multi-Purpose Bondable Reinforcement Ribbon is used to replace a single extracted anterior tooth using the patient's own tooth.  相似文献   
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A case of primary malignant melanoma in the mediastinum presenting as recurrent laryngeal nerve palsy is reported. Tissue biopsy at mediastinotomy yielded a diagnosis of malignant melanoma. The mass was fixed to the left aspect of the trachea and to the upper border of the left main bronchus and could not be removed surgically. Further extensive clinical and radiological investigations revealed no evidence of tumor elsewhere in the body.  相似文献   
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