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71.
磁性明胶微球体内分布实验研究   总被引:11,自引:0,他引:11  
对磁性明胶微球进行了同位素标记。用γ-闪烁照相技术观察了磁性明胶微球在兔体内的分布。结果表明:靶部位的放射活性加磁场是未加磁场的15倍,而且施加磁场时间长和磁场强度大有利于磁性明胶微球定位于靶区。文中也介绍了自行设计的外加磁场装置。  相似文献   
72.
Patients with the syndrome of chronic daily headache often report migrainous symptoms and consequently are diagnosed as having a primary headache syndrome. We report two cases of idiopathic intracranial hypertension causing chronic daily headache with migrainous features in the absence of associated papilledema.  相似文献   
73.
康继超  魏树礼 《药学学报》1997,32(7):536-541
为制备能用于清除骨髓中癌细胞的磁性微球,首先合成了单分散、大粒径的多孔聚苯乙烯交联微球,借助微球多孔结构对其进行磁化。探讨了影响磁化效果的主要因素。为使其与单抗连接紧密,在微球表面聚合了一层聚丙烯醛膜,使其表面带上易与单抗反应的醛基。同时测定了所制微球的磁响应性。X-射线衍射证明磁性物质为γ-Fe2O3。  相似文献   
74.
Summary: Oral ofloxacin has been successfully used in our centres for the primary treatment of peritonitis complicating continous ambulatory peritoneal dialysis (CAPD). In view of the progressive rise in the resistance rate to ofloxacin among peritoneal bacterial isolates, a study was conducted to determine if oral ofloxacin remains a viable first line treatment for CAPD peritonitis in our centres and if the result can be improved by changing from an oral to an intraperitoneal (i.p.) route. In patients on three 2 L daily CAPD exchanges, ofloxacin given at the i.p. dosage of 200 mg loading followed by 25 mg/L of peritoneal dialysate achieved overnight trough peritoneal levels which are at least four times the minimal 90% inhibitory concentration (MIC90) of most bacterial pathogens without significant accumulation in the systemic circulation. This i.p. dosage was therefore chosen for the clinical study and the result was compared to that using ofloxacin given in the oral dosage of 400 mg loading followed by 300 mg once daily as maintenance. of all the recruited episodes, 35 were eligible for analysis. the overall primary cure rate including primary failures and relapses was 55.6% (10/18) in the oral treatment group and 70.6% (12/17) in the i.p. treatment group. the corresponding figures for gram positive bacterial (g +) infections were 36.4% and 50%, for gram negative bacterial (g -) infections were 66.7 and 80% and for culture negative infections were 75 and 80%. In culture positive cases, all treatment failures were due to resistant infections which were observed in 42.3% of all bacterial isolates, 47.1% of g + isolates and 33.3% of g - isolates. Due to the high background level of bacterial resistance among our CAPD population, ofloxacin monotherapy given either by the oral or the i.p. route can no longer be recommended for the primary treatment of CAPD peritonitis.  相似文献   
75.
Abstract A transjugular liver biopsy was performed on 60 patients. Specimens were successfully obtained from 57 (95%) patients. Specimens obtained from cirrhotic patients were frequently small-sized/fragmented. The wedge hepatic venous pressure and hepatic venous pressure gradient were higher in patients with small-sized/fragmented specimens than those with non-fragmented specimens (16.3 ± 6.4 vs 12.3 ± 4.9 and 10.9 ± 6.2 vs 7.3 ± 3.4 mmHg, P <0.05, respectively). During the same period of time, percutaneous liver biopsies were consecutively performed on 277 patients. The liver specimens by transjugular method were generally smaller (0.63±0.58 vs 1.50±0.86 cm, P <0.001) and more fragmented (63% vs 16%, P <0.01) than those obtained by percutaneous method. Biopsy specimens obtained for diagnosis by the former method were inadequate from 6 (10%) patients and by the latter route were inadequate from 7 (2%) patients. Subcapsular haematoma in one patient was associated with the transjugular liver biopsy. Minor complications occurred in three patients: neck haematoma in two and paroxysmal supraventricular tachycardia during the procedure in one. In comparison, percutaneous liver biopsy was followed by minor complications in 20 patients and major complications in four patients. It is concluded that transjugular liver biopsy is a safe, valuable and alternative procedure to obtain liver specimens, especially in patients who were contraindicated for percutaneous liver biopsy.  相似文献   
76.
Abstract The relationship between the severity of cirrhosis and systemic and hepatic haemodynamic values was evaluated in 193 patients with cirrhosis, most of whom were diagnosed with post-necrotic cirrhosis. It was found that the hepatic venous pressure gradient and cardiac output in Pugh's A patients (13.6 ± 4.8 mmHg and 6.2 ± 1.6 L/min, mean ± s.d.) were significantly lower than in both Pugh's B (16.8 ± 4.3 mmHg and 7.3 ± 2.1 L/min) and Pugh's C (18.8 ± 5.5 mmHg and 7.4 ± 2.3 L/min) patients ( P < 0.01), respectively. In contrast, the systemic vascular resistance in Pugh's A patients (1232 ± 369 dyn/s per cm5) was significantly higher than in both Pugh's B (1016 ± 345 dyn/s per cm5) and Pugh's C (935 ± 234 dyn/s per cm5) patients ( P < 0.01), respectively. Additionally, not only was there a positive correlation found between Pugh's score and cardiac output and hepatic venous pressure gradient, but a negative correlation was found between Pugh's score and systemic vascular resistance. It was also confirmed that the degree of portal hypertension and the hyperdynamic circulation were more severe in patients with ascites than in those without ascites. However, there were no statistically significant differences in hepatic venous pressure gradient among patients with F1, F2 and F3 esophageal varices (15.7 ± 4.0, 17.0 ± 4.8 and 18.0 ± 4.8 mmHg, respectively). It is concluded that in those patients with cirrhosis, the severity of cirrhosis is closely related to the degree of the hyperkinetic circulatory state and portal hypertension.  相似文献   
77.
Propranolol is used clinically as a prophylactic drug to prevent oesophageal variceal bleeding in cirrhotic patients with portal hypertension. Vascular hyporesponsiveness is a common characteristic of the portal hypertensive state. The present study aimed to investigate whether chronic administration of propranolol could improve vascular responsiveness in portal hypertensive rats. Portal hypertension was induced by partial portal vein ligation (PVL). Sham-operated rats served as controls. There were four study groups: PVL–propranolol group (portal hypertensive rats receiving propranolol), PVL–vehicle group (portal hypertensive rats receiving saline), sham–propranolol group (sham-operated rats receiving propranolol) and sham–vehicle group (sham-operated rats receiving saline). Propranolol (30 mg kg?1 day?1) or saline was given for 9 days via gastric gavage starting 1 day before ligation and thereafter. Then, the superior mesenteric artery was removed from each group for contractile study after haemodynamic measurement. In portal hypertensive rats, propranolol significantly alleviated the hyperdynamic state, including portal pressure, cardiac index and total peripheral resistance in the treated group compared with the vehicle group. The maximal contractile responses to KCl and vasopressin in mesenteric artery were significantly greater in the sham–vehicle group than in the PVL–vehicle group. Long-term propranolol treatment enhanced the contractile reactivity of mesenteric artery to KCl and vasopressin in PVL rats, and the contractile profiles were corrected towards those in sham-treated animals. In contrast, propranolol treatment decreased heart rate, mean arterial pressure and cardiac index but did not alter the contractile responsiveness of sham-operated rats These results showed that, in portal vein stenosed rats, long-term treatment with propranolol improved arterial contractile reactivity together with portal pressure reduction. The propranolol effect on vascular reactivity is probably related to haemodynamic improvement, instead of a direct contractile effect on the vasculature.  相似文献   
78.
阿克拉霉素A聚氰基丙烯酸异丁酯毫微粒的冻干针剂,能明显抑制体外培养人肝癌细胞株7703的生长,IC50为0.28μg·ml-1。在0.8μg·ml-1浓度时,克隆形成抑制率为90%,抑制作用有明显剂量依赖关系而未见明显时间依赖关系。静脉给药后,对常位移植人肝癌模型裸小鼠的抑瘤率为86.84%,肿瘤细胞增殖活性阳性率为20.83%。体内外均显示明显的抗肝癌活性,且体内抗肝癌活性比阿克拉霉素A冻干针剂强。  相似文献   
79.
80.
目的:从细胞水平,观察扶元起萎,养荣生肌的中药制剂肌萎灵注射液对原代培养鼠胚脊髓运动神经元的保护作用。方法:实验于2004-03/2005-03在解放军第三军医大学完成。实验分组:清洁级SD雌性孕鼠,孕期10~14d。应用密度梯度离心法分离鼠胚脊髓运动神经元进行原代培养,运动神经元培养72h后,按培养板及孔分为4.5μg/L肌萎灵组(肌萎灵注射液,含生药0.9g/mL)、9μg/L肌萎灵组、45μg/L肌萎灵组、力如太组(力如太R利鲁唑片,应用时经0.9%NaCl-0.01NHCl溶解)和对照组。实验处理:各组分别加入用新鲜培养基稀释为0.5%(终浓度4.5μg/L)、1%(终浓度9μg/L)、5%(终浓度45μg/L)的肌萎灵注射液,力如太组加入利鲁唑(终浓度10μmo/L),对照组加入等量新鲜培养基。实验评估:①共同培养3d用四甲基偶氮唑盐法观察其对细胞活力的影响,以吸光度表示。②采用NF-200免疫组织化学染色并进行图像分析,测定神经突起主干长度。结果:①培养的运动神经元活力状态比较:4.5,9,45μg/L肌萎灵组培养运动神经元活力显著增强,与对照组相比,差异有显著性意义(0.317±0.054,0.396±0.087,0.329±0.097,0.230±0.130,P<0.05)。力如太组细胞生长与对照组相比无显著差异(0.266±0.141,0.230±0.130,P>0.05)。②脊髓运动神经元突起生长情况结果:4.5μg/L肌萎灵组和9μg/L肌萎灵组可促进其生长,与对照组相比,差异有显著性意义[(315.96±32.32),(373.46±80.24),(159.71±48.95)μm,P<0.05]。结论:肌萎灵注射液可增强运动神经元活力,促进脊髓运动神经元突起的生长。  相似文献   
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