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101.
102.
肉毒碱治疗TPN大鼠肝脂肪变性的研究   总被引:4,自引:1,他引:3  
Liang L  Luo S  Zheng J  Huang J 《中华外科杂志》1999,37(8):500-502,I033
目的 探讨在全胃肠外营养(TPN)中补充肉毒碱减轻肝脂肪变性的作用。方法 18只正常Wistar大鼠和19只肝硬化Wistar大鼠分别随机分为6组,A1组、A2组,自由进食和进水(各6只);B1组、B2组,TPN(分别6只、7只);C1组、 ,TPN加肉毒碱(各6只)。各组实验结束后测肝功能,肝脂肪及行肝脏的组织学检查。结果 TPN组肝内脂肪显著2,TPN+肉毒碱组肝内脂肪明显减少。结论 在TPN  相似文献   
103.
就《伤寒论》水气的涵义、致病特点、形成与发病、证治等方面进行了分析和探讨。认为:水气是一个病理概念,具有病理产物和致病因素的双重性,其本质是体内停蓄之水,其致病过程具有动而不居的特点;痰饮、水肿、湿痹皆是水气为患。水气的形成机制是阳虚,阳不制阴。治疗以“温药和之”为常法,振奋阳气以祛除水气;非尽以温药和之为变法,攻逐、清热、滋阴皆在其中。  相似文献   
104.
大鼠实验性视网膜光损伤中的视细胞凋亡   总被引:7,自引:1,他引:6  
目的 进一步探讨视网膜光损伤的发病机制。 方法 20只Wistar大鼠分为实验组、对照组,分别在光照后12,24,36小时摘除眼球,视网膜组织行HE染色和核苷酸末端转移酶介导的DUTP缺口翻译法(TdT-mediated dUTP nick end labelling method,TUNEL)标记凋亡细胞。 结果 光照后12小时,视杆细胞外节出现少量空泡变性;24小时后,外核层出现明显的细胞核破碎、浓染和DNA裂解;36小时后,视杆细胞内、外节溶解,外核层大量细胞核丢失。 结论 视细胞凋亡是大鼠实验性视网膜光损伤的重要机制之一。 (中华眼底病杂志, 1999, 15: 167-169)  相似文献   
105.
Acute toxic inhalation by irritant, and particularly oxidant, gases has until recently been considered to be no more complicated conceptually than a chemical burn of the epithelial surface. More recently, however, toxic inhalation has been appreciated to be a complex process involving biochemical, morphological and functional changes which are quantitatively similar, although inducible by different agents. Recent advances in pulmonary pathophysiology, inhalation toxicology, and particularly endothelial biology have clarified the events occurring at the moment of, and immediately following, exposure to oxidant gases. Studies of the pathophysiologic mechanisms associated with toxic inhalation by oxidant gases have been relatively static, however. Implications of recent findings in related fields illuminate the pathophysiology of toxic inhalation. Several principal speakers in this workshop are collaborating in an effort to develop a research facility for the study of toxic inhalation injury. This would be an international registry to serve as a teaching and research facility for documentation of cases of occupational and environmental toxic inhalation, considered as lung injury resulting from the inhalation of a toxic substance in a workplace setting or an uncontrolled release affecting residents of a community. The registry, as proposed, would encourage submissions by clinicians and institutions of a data set on each patient and on each incident; the registry would further encourage long-term follow-up of subjects and documentation of residual effects.Work presented at the 23rd Congress on Occupational and Environmental Health in the Chemical Industry (Medichem 1995) The Chemical Industry as a Global Citizen - Balancing Risks and Benefits, 19–22 September 1995, Massachusetts Institute of Technology, Cambridge, Massachusetts  相似文献   
106.
The purpose of this study was to determine the effects of vasoactive treatment with dopamine (DO), dopexamine (DX), and dobutamine (DOB) on hemodynamics, oxygen transport and hepatic venous oxygen saturation (SvhO2) after orthotopic liver transplantation (OLT). A pulmonary artery catheter was inserted into the right hepatic vein of 17 OLT patients. Timed infusion of DO, DX, and DOB was performed at the following rates: DO at 4 and 8 g/kg per minute, and DOB at 5 and 10 g/kg per minute. Hemodynamics, oxygen transport variables, and SvhO2 were assessed. Each catecholamine induced a significant increase in cardiac index, oxygen delivery, and SvhO2. Mean arterial pressure was increased during DO and DOB, but significantly reduced during DX. Each inotrope increased oxygen delivery in parallel with SvhO2, suggesting a corresponding increase in hepatic oxygen supply. Therefore, it appears that each vasoactive drug may be utilized in OLT patients to provide oxgen delivery without impairment of splanchnic oxygenation.  相似文献   
107.
The present report evaluates the efficacy and safety of percutaneous interstitial laser tissue ablation of the liver in nine New Zealand rabbits. A Nd: YAG laser was coupled to a quartz fibreoptic guide (600 m) with a flat tip. The fibre and a thermocouple were placed in the lumen of two Chiba needles (18G) and these were inserted into the liver 10 mm apart under ultrasound guidance. The laser was fired for 5 min at 1, 3 and 5 W power, respectively, in three groups of rabbits. There were no acute complications and all the rabbits except one survived until the established time of sacrifice. The procedure induced a cavity surrounded by a zone (about 10 mm) of coagulative necrosis. After 2 weeks a strong peripheral inflammatory response was evident and after 4 weeks a capsule of connective tissue enclosed the lesions. Our study seems to offer a safe and rapid technique producing a guaranteed kill radius for the treatment of small hepatic neoplasms. Correspondence to: C. M. Pacella  相似文献   
108.
By intra-adnexal injection of glucose in the rabbit embryo, we were able to stimulate all the anomalies associated with "Amniotic Disease". Since we were even able to obtain amniotic bands, this study provides an excellent experimental model of this disease. Resulting lesions occur early in development, corresponding to the first trimester of human gestation. All of the anomalies can ultimately be explained by the destruction of the most superficial cells: epiblastic cells of the embryo and the amnion, subjacent mesenchyme, and endothelial cells. The subsequent lack of interaction between these cells and the importance of the anatomical localizations of resulting hematomas can lead to the pathogenetic approach to this disease. In light of the present study, the disease appears to be caused by an external factor within the amniotic fluid. The exact nature of the destructive agent(s) remains a mystery in man.  相似文献   
109.
Age-dependent effects of technical pentachlorophenol (PCP) on male rat livers were investigated after a 15 day treatment with PCP, 30 mg/kg/d body weight. The liver tissues were investigated morphometrically at light and electron microscopical levels. Statistically significant alterations of nuclei and organelles of the hepatocytes were described.This work was supported by the Deutsche Forschungsgemeinschaft — Biologie des Alterns — Th 83/14  相似文献   
110.
Spontaneous portosystemic shunts are commonly found in cirrhotic patients. Not yet established is their role after orthotopic liver transplantation (OLTx), especially when an increase in portal pressure develops, as during early acute rejection. In this study, 34 cirrhotic patients in a series of 70 OLTx are considered. Each patient had preoperative angiographic assessment, and, in 21 (62%), large spontaneous portosystemic shunts were evident. In 12 cases the shunts were not affected by the surgical procedure and were present during the postoperative period; in 9 the hepatectomy itself involved interruption of the shunts. The patient population was divided into two groups: patients with postoperative shunts (n=12) and those without (n=22). The two groups were similar in age, sex, Child's stage, transplantation variables, and number and grade of rejection episodes. However, mean transaminases (AST) values in the first 2 weeks were significantly higher levels in shunt versus nonshunt patients (421±335 vs 183±126; P<0.025), and this was even more evident when rejection occurred (626±375 vs 195±129; P<0.001). Furthermore, during an acute rejection reaction, three cases showed a true steal phenomenon through the large reopened shunts with ischemic damage to the grafts. The data indicate a possible detrimental effect of the spontaneous shunts on graft perfusion and suggest the prophylactic surgical interruption of the residual shunts during the transplantation.  相似文献   
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