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91.
Frequency of pancreatitis after endoscopic retrograde cholangiopancreatography with iopromid or iotrolan: a randomized trial 总被引:1,自引:0,他引:1
Blood isotone contrast media is considered to be less toxic to vascular and pancreatic duct endothelium than high-osmolar
contrast media. In this study we assessed the impact of a low-osmolar contrast agent compared with a blood isotone product
on pancreatic damage induced by endoscopic retrograde cholangiopancreatography (ERCP) and endoscopic retrograde sphincterotomy
(EST). In a prospective trial 42 consecutive ERCP/EST patients were randomized to receive either iopromid, a low-osmolar non-ionic
contrast agent (770 mosmol/kg H2O), or iotrolan, a blood-isotone non-ionic product (320 mosmol/kg H2O). The endoscopies were performed by two experienced endoscopists. Forty patients were included in the study. Blood samples
were collected before and 40 min, 2, 4, 6 and 24 h after the endoscopic procedure. Samples were analysed for pancreatic serum
enzymes, acute-phase proteins and blood counts. A clinical pain score was investigated. Post-ERCP pancreatitis was diagnosed
in 2 patients in the iopromid group and in 5 patients in the iotrolan group. There was no significant difference between groups
in the time course of pancreatic serum enzymes, acute-phase proteins or in the pain score. Due to the small number of patients
in this study, only stronger differences caused by the two contrast media could have led to statistically significant results.
We did not observe statistically significant differences in comparing iotrolan and iopromid concerning ERCP/EST-induced pancreatic
damage.
Received: 26 February 1999; Revised: 14 May 1999; Accepted: 9 June 1999 相似文献
92.
Ensaculin interacts with various neurotransmitter systems (e.g., dopaminergic, serotoninergic, glutamatergic) and was originally designed for the treatment of dementia. In the present study Ensaculin was tested for its possible reduction of glutamate-induced hydroxyl free radical formation in vivo. The microdialysis experiment was carried out in non-anaesthetized Wistar rats, which were implanted with a microdialysis probe into the striatum. Salicylate (10 nmol/2 microl/min) was incorporated into the perfusion fluid to measure indirectly hydroxyl radicals indicated by 2,3-dihydroxybenzoic acid (DHBA) formation. After baseline recording, glutamate (100 or 500 nmol/2 microl/min) was perfused through the microdialysis probe (CMA 12, 4 mm, flow rate 2 microl/min). Ensaculin (0.1, 1 and 10 mg/kg), MK-801 (1 mg/kg) or saline was injected i.p. 20 min after the onset of glutamate perfusion (500 nmol/2 microl/min). Glutamate (100 nmol/2 microl/min) and (500 nmol/2 microl/min) perfusion produced a 2.6- and 17-fold increase of 2,3-DHBA, respectively. Treatment with Ensaculin (1 and 10 mg/kg i.p. ) significantly antagonized the formation of 2,3-DHBA, to values of 60.5% and 56.7% of control levels, respectively. In comparison, MK-801 attenuated 2,3-DHBA levels, to values of 65.8% compared to control values. Ensaculin may be useful in the treatment of neurodegenerative disorders associated with elevated hydroxyl free radicals and excitotoxicity. 相似文献
93.
The importance of free hydroxyl radicals to hypoxia preconditioning 总被引:14,自引:0,他引:14
Hypoxia preconditioning states that a sublethal hypoxia period will afford neuroprotection against a second harmful event. In our experiments, we carried out a procedure for the development of hypoxia preconditioning in adult male Wistar rats using hypoxic exposure (9% O(2); 91% N(2)) for 1 h. The protection against pentylenetetrazol (PTZ)-induced seizures was studied. For this, rats were tested by a single injection of PTZ (55 mg/kg i.p.) on days 1-21 after hypoxia exposure. The hypoxia exposure significantly prevented the development of acute PTZ convulsion at different times after hypoxia. The present study was designed to determine the effect of N-t-butyl-alpha-phenylnitrone (PBN), an electron-trapping agent and free radical scavenger, on hypoxia preconditioning against PTZ seizures 7 days after hypoxia exposure. PBN abolished the protective action of hypoxia exposure. The generation of free hydroxyl radicals in the brains of animals exposed to hypoxia was determined in a second experiment. For this purpose, the rats were i. p. pretreated with 30 mg/kg PBN and NaCl, respectively, 20 min before the start of hypoxia exposure. Forty-five minutes later the rats were i.p. injected with 300 mg/kg sodium salicylate and once again exposed to hypoxia for 15 min. Immediately after that the animals were decapitated and the free hydroxyl radicals and the salicylate content were estimated in the whole brain without cerebellum. Hypoxia preconditioned animals pretreated with NaCl showed a significantly higher extent of free hydroxyl radicals in the brain compared with PBN-injected preconditioned animals and with naive and sham exposed controls. The results pointed out that the generation of free reactive oxygen species under hypoxic conditions in the brain is involved in the development of the hypoxic preconditioning phenomenon. 相似文献
94.
Hyperbaric oxygenation induced tolerance against focal cerebral ischemia in mice is strain dependent 总被引:18,自引:0,他引:18
Prass K Wiegand F Schumann P Ahrens M Kapinya K Harms C Liao W Trendelenburg G Gertz K Moskowitz MA Knapp F Victorov IV Megow D Dirnagl U 《Brain research》2000,871(1):146-150
SV129 or C57BL/6 mice were exposed to hyperbaric oxygenation (HBO, 5 days, 1 h every day, 100% O(2) at 3 atm absolute). One day after the 5th HBO session focal cerebral ischemia was induced. In SV129 mice, HBO induced tolerance against permanent focal cerebral ischemia (n=42, mean infarct volume reduction 27%, P=0.001), but not against transient (30 or 60 min) focal cerebral ischemia. In the C57BL/6 strain of mice, HBO did not induce tolerance against focal cerebral ischemia, even when the duration of ischemia or the HBO protocol were modified. For the first time we demonstrate that HBO can induce tolerance to focal cerebral ischemia, but this effect is strain dependent. 相似文献
95.
OBJECTIVE: Release of oxygen free radicals occurs following cerebral ischemia. Studies show that oxygen free radicals mediate ischemic brain injury. CoQ10 is a potent free radical scavenger and may offset brain injury associated with reperfusion. We tested exogeneous CoQ10 as a neuroprotectant in rats following both global and focal ischemic insults. METHODS: Rats were subjected to either 4-vessel occlusion ischemia (4-VO, 10 min occlusion, 7-day survival) or middle cerebral artery occlusion (MCAO, 120 min-occlusion, 22.5 h survival). Regional cerebral blood flows (rCBF) and physiological variables such as blood pressure, pO2, pCO2, plasma glucose and hematocrit were monitored and measured in focal ischemia. The animals were randomized to receive treatments of either phosphate buffered saline (PBS) vehicle or CoQ10 following global or focal ischemia. Injection times were at the end of ischemia and 3 h later for both models of ischemia. Histological outcomes are expressed as a percentage of hippocampal CA(1) cell injury in global ischemia or percentage of cortical infarct over that of non-ischemic hemisphere in focal ischemia. RESULTS: In global ischemia, animals treated with PBS vehicle and CoQ10 had 86+/-5% (n=8) and 83+/-10% (n=8), respectively, of hippocampal CA(1) cell injury (P>0.05). The percentage of infarct volumes in animals following focal ischemia were 23+/-9% (control, n=10) and 25+/-9% (CoQ10, n=10). There were no temperature or physiological differences between the two treatment groups. CONCLUSION: Acute treatment with CoQ10 via intraperitoneal injection does not prevent neuronal injuries following global and focal ischemia. 相似文献
96.
Four patients harbouring a colloid cyst of the 3rd ventricle were operated on endoscopically. With the "classical" monoportal technique, through a precoronal burr hole only partial removal could be achieved in the first case. As the crucial point of the procedure is the safe dissection of the cyst from the thela chorioidea and from the internal cerebral veins, adequate control of the posterior rim of the foramen of Monro and the roof of the 3rd ventricle is mandatory. Accordingly in other three cases a CT-guided biportal endoscopic technique was applied, which permitted radical removal of the entire cyst with maximum safety. CT-guidance is essential for optimal planning after careful study of the individual anatomy. In this way the rigid scopes are moved exclusively along their own axes throughout the procedure, the resulting brain damage thereby being minimal. With regard to all circumstances of the procedure, the use of flexible endoscopes appears to be inappropriate and biportal endoscopy offers itself as the method of choice. 相似文献
97.
目的 探讨铅对分离的小鼠海马细胞内游离钙的影响及其及L型钙通道的作用。方法 采用低浓度胰蛋白酶消化法分离小鼠海马细胞 ,并以莹光指标剂 (Fura 2 )作Ca2 荧光探针 ,用双波长荧光法测定海马细胞 [Ca2 ] i。结果 铅可致分离的小鼠海马细胞 [Ca2 ] i 升高 [由静息时的 (2 0 3 4± 10 86)nmol L升至 (4 2 3 3± 19 2 6)nmol L] ,而不论胞外是否有钙 ;铅可抑制钾诱发海马细胞 [Ca2 ] i 升高 ,尼莫地平可加强这种抑制作用 ,而BayK864 4则可部分消除这种抑制作用。结论 铅可致分离的小鼠海马细胞 [Ca2 ] i 升高作用与胞内钙库释放有关 ;铅的抑制钾诱发海马细胞 [Ca2 ] i 升高作用与其抑制L型钙通道有关。 相似文献
98.
Neoadjuvant chemotherapy with cisplatin, aclacinomycin A, and mitomycin C for cervical adenocarcinoma – a preliminary study 总被引:3,自引:0,他引:3
T. Saito M. Takehara R. Lee T. Fujimoto M. Nishimura R. Tanaka E. Ito K. Adachi & R. Kudo 《International journal of gynecological cancer》2004,14(3):483-490
Between 1989 and 2002, 28 patients with locally advanced cervical adenocarcinoma (bulky IB-IIIB) were recruited for a pilot study aimed at evaluation of the effectiveness of neoadjuvant chemotherapy with cisplatin, aclacinomycin-A, and mitomycin-C (PAM), followed by radical surgery. This regimen was administrated intra-arterially or intravenously. In addition to patients treated with PAM, we retrospectively analyzed the prognoses of 26 patients in stage I and II, who had been treated between 1975 and 1981 with radical surgery with/without radiation therapy. Twenty-eight patients received PAM therapy as neoadjuvant chemotherapy, and 75.0% of the 16 intra-arterially infused patients showed a response, as did 66.7% of the 12 intravenously infused patients. There was a significant difference in the 5-year prognosis of stage II (PAM group, 72.9%; without-PAM group, 36.4%). The results suggest that, as the free space in the parametrium is widened by neoadjuvant chemotherapy with PAM, it is possible that the tumor could be completely resected by radical hysterectomy. Thus, neoadjuvant chemotherapy with PAM is expected to improve the survival rate of patients with advanced cervical adenocarcinoma by the preliminary study. However, the survival rates of stage II with lymph node metastasis in the without-PAM group seem low, and we must also consider that the various technologies to evaluate and treat the cervical adenocarcinomas, e.g. computed tomography, magnetic resonance imaging, and surgical equipments, had improved during 1989-2002 than was the scenario during 1975-1981, and these improvements contributed to better prognosis. A prospective-randomized study is needed to assess the value of this approach compared with standard management. 相似文献
99.
[目的]从缺血再灌注损伤的主要病理过程出发,研究了益肾补气活血法对脑缺血再灌注损伤的保护作用。[方法]用日龄62d的Wistar大鼠采用Warner方法做成脑缺血再灌注模型,平行观察假手术、盐水对照、益肾补气活血法对照3个组脑组织自由基和脑含水量的变化。[结果]益肾补气活血法中药组脑组织自由基和脑含水量明显低于盐水组。[结论]益肾补气活血法在一定程度上可以抑制自由基的产生及连锁反应的发生,促进神经细胞结构及功能的恢复,延缓神经细胞的坏死,具有治疗的多向性及疗效的准确性。 相似文献
100.
醒脑静注射液对脑缺血再灌注氧化损伤的实验研究 总被引:11,自引:0,他引:11
[目的]研究中药醒脑静注射液对沙土鼠急性脑缺血再灌注损伤的作用。[方法]采用沙土鼠双侧颈总动脉夹闭制作沙土鼠急性全脑缺血模型,观察干预性腹腔注射西药尼莫地平和中药醒脑静注射液对缺血再灌注急性期沙土鼠脑组织中MDA含量和SOD活力的影响。[结果]西药尼莫地平和醒脑静注射液均能显著提高脑缺血再灌注后SOD活力和降低MDA含量,醒脑静注射液疗效和西药尼莫地平无显著差异,而醒脑静大中小剂量组之间有较显著的差异,疗效随剂量的增加而增大。[结论]醒脑静注射液作为抗自由基损伤的中药和西药尼莫地平有相当的疗效。 相似文献