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991.
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
992.
993.
Kassner A Annesley DJ Zhu XP Li KL Kamaly-Asl ID Watson Y Jackson A 《Journal of magnetic resonance imaging : JMRI》2000,11(2):103-113
Dynamic susceptibility contrast-enhanced magnetic resonance (MR) imaging in tumors is restricted by relaxivity effects, which may obscure any abnormality of first-pass kinetics in the re-circulation phase. The purposes of this study were a) to document the magnitude of relaxivity effects with a variety of commonly used MR susceptibility imaging techniques; and b) to determine whether the re-circulation phase of the first-pass curve in tumors differs from that in normal tissue. We have confirmed that residual relaxivity effects can be eliminated from dynamic susceptibility contrast-enhanced data by several techniques. Application of these methods to enhancing vascular tumors allows detection of abnormalities in the re-circulation phase, which would otherwise be obscured. These abnormalities are independent of relative cerebral blood volume (rCBV) and presumably represent deviations from the predicted gamma variat flow pattern seen in normal tissues. We believe that the parameter rR described here provides an indicator of the chaotic nature of neovascular angiogenesis, which may be of benefit in diagnosis and management. 相似文献
994.
Artery and vein separation using susceptibility-dependent phase in contrast-enhanced MRA 总被引:6,自引:0,他引:6
Wang Y Yu Y Li D Bae KT Brown JJ Lin W Haacke EM 《Journal of magnetic resonance imaging : JMRI》2000,12(5):661-670
In magnetic resonance angiography, contrast agents are frequently used to help highlight arteries over background tissue. Unfortunately, enhancing veins hamper the visualization of arteries when data are collected over a long period of time after the arterial phase of the contrast agent. To overcome this problem, we have developed a novel imaging and postprocessing method that is capable of eliminating veins by utilizing the susceptibility difference between veins and surrounding tissue. This method was applied in the peripheral vasculature where the vessels are predominantly parallel to the main field and where the blood oxygen level-dependent effect is most pronounced. Results are presented for both long (15.8 msec) and short echo times (7.8 msec) and for sequential and centrally reordered acquisition schemes. The short echo scan approach appears to be the most promising, making it possible to obtain good suppression of the venous signal even when the timing is not perfect or when repeat scans are necessary. 相似文献
995.
Propofol (Diprivan(TM); AstraZeneca, Wilmington, DE) is a commonly used drug for the induction of general anesthesia in the ambulatory setting. With the availability of a new bisulfite-containing generic formulation of propofol, questions have arisen regarding its cost effectiveness and safety compared with Diprivan(TM). Two hundred healthy outpatients were randomly assigned, according to a double-blinded protocol, to receive either Diprivan(TM) or bisulfite-containing propofol 1.5 mg/kg IV as part of a standardized induction sequence. Maintenance of anesthesia consisted of either desflurane (4%-8% end-tidal) or sevoflurane (1%-2% end-tidal) in combination with a remifentanil infusion (0.125 microg x kg(-1) x min(-1) IV). Patient assessments included pain on injection, induction time, hemodynamic and bispectral electroencephalographic changes during induction, emergence time, and incidence of postoperative nausea and vomiting. The two propofol groups were comparable demographically, and the induction times and bispectral index values during the induction were also similar. However, the bisulfite-containing formulation was associated with less severe pain on injection (5% vs 11%), with fewer patients recalling pain on injection after surgery (38% vs. 51%, P<0.05). None of the patients manifested allergic-type reactions after the induction of anesthesia. The acquisition cost (average wholesale price in US dollars) of a 20-mL ampoule of Diprivan(TM) was $15 compared with $13 for the bisulfite-containing propofol formulation. Therefore, we concluded that the bisulfite-containing formulation of propofol is a cost-effective alternative to Diprivan(TM) for the induction of outpatient anesthesia. Implications: Bisulfite-containing propofol and Diprivan(TM) (AstraZeneca, Wilmington, DE) were similar with respect to their induction characteristics; however, the generic formulation was associated with a smaller incidence of injection pain. Assuming that the drug costs are similar, these data suggest that the bisulfite-containing formulation of propofol is a cost-effective alternative to Diprivan(TM). 相似文献
996.
The effects of ropivacaine on sodium currents in dorsal horn neurons of neonatal rats 总被引:1,自引:0,他引:1
We used a whole cell patch clamp technique to study the effects of ropivacaine on rat dorsal horn neurons. Under voltage clamp, ropivacaine (10-400 microM) produced a dose-dependent inhibition of sodium current. From a holding potential (V(h)) of -80 mV, sodium currents evoked by test pulses to 0 mV were inhibited by ropivacaine with a mean drug concentration required to produce 50% current inhibition (IC(50)) value of 117.3 microM, which was more than the value of the bupivacaine (IC(50) 53.7 microM). The inhibition effect of ropivacaine was also voltage-dependent. Current evoked from a V(h) of -60 mV was inhibited by ropivacaine with a mean IC(50) value of 74.3 microM, which was less than that obtained at the V(h) of -80 mV. The inhibition effect of ropivacaine on sodium current was use dependent. Repeated activation by a train of depolarizing pulses (5 Hz, 20 ms) increased the inhibitory effects of ropivacaine. The ratio amplitudes of the 20th to the first pulse were 91.2% and 71.1%, respectively, in the absence and presence of ropivacaine (50 microM). Ropivacaine also produced a significant hyperpolarizing shift of 11 mV in the steady-state inactivation curve of sodium current. The inhibition of ropivacaine on the sodium channel may contribute to the mechanism of action of local anesthetics during epidural and spinal anesthesia. 相似文献
997.
目的 通过对梅毒检测结果的分析,掌握出入境人员的梅毒感染情况,有针对性的进行梅毒的防治。方法 对24503名经天津口岸出入境的各类人员进行梅毒血清学检测,并对检测结果进行统计分析。结果 24503名出入境人员中共检出梅毒阳性39例,阳性率为1.59%o,分析发现各年份检出梅毒阳性率呈逐年递增的趋势,不同职业人群中船员的梅毒阳性率为2.01‰,远远高于其他人群的0.88‰。结论 出入境船员作为一个特殊人群,是梅毒感染的高危人群,需加强卫生保健意识,减少感染梅毒的机会,进一步说明梅毒血清学检测在国境口岸传染病监测中的重要性。 相似文献
998.
补骨方治疗膝骨性关节炎的疗效观察 总被引:7,自引:0,他引:7
目的 探讨应用补骨方治疗膝骨关节炎的疗效。方法 临床应用补骨方和芬必得治疗老年性膝骨性关节炎 6 0例 4周 ,并比较随访疗效。结果 治疗后两组患者症状平均分值、日常活动功能障碍平均分值和总评分平均分值较治疗后显著升高 ,膝关节临床症状明显减轻 ,关节功能显著改善 ,比较具有显著性差别 (P <0 0 1)。经统计学处理 ,两组膝关节日常生活活动评分治疗前后。两组临床资料没有显著差异 (P >0 0 5 ) ,具可比性。结论 补骨方能明显改善膝骨关节炎患者的临床症状和关节功能。 相似文献
999.
目的探讨临床上对非淋菌性尿道(宫颈)炎合并盆腔感染有效的治疗方法。方法将妇产科及性病科门诊确诊的非淋菌性尿道(宫颈)炎合并盆腔感染201例病人随机分为2组,治疗组采用头孢曲松纳加阿奇霉素治疗,对照组采用头孢曲松纳加口服美满霉素治疗。结果治疗组治愈率为80.95%,总有效率为97.14%;对照组治愈率为58.33%,总有效率为69.79%。两者的,临床治愈率及有效率有显著性的差异(P<0.005)。结论头孢曲松纳加阿奇霉素静脉给药治疗非淋菌性尿道(宫颈)炎合并盆腔感染取得良好的治疗效果,较头孢曲松纳加美满霉素效果有显著性提高。 相似文献
1000.