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41.
D R Robertson A G Renwick N D Wood N Cross B S Macklin J S Fleming D G Waller C F George 《British journal of clinical pharmacology》1990,29(1):47-53
1. Simultaneous radioisotopic (99Tc-DTPA) gastric emptying measurements and paracetamol pharmacokinetic studies were performed in eight healthy male volunteers with and without levodopa (125 mg orally). 2. In the absence of levodopa gamma camera imaging showed rapid mono or biexponential emptying in all subjects and the plasma concentration-time curves for paracetamol displayed a single major peak. 3. In the presence of levodopa the time to 90% emptying was prolonged from 32 +/- 24 min to 81 +/- 20 min (P less than 0.01). Gastric emptying was interrupted by a plateau phase in six subjects and this pattern of emptying was associated with double peaks in the plasma concentration-time curves of both levodopa and paracetamol. The time to the end of the plateau phase of emptying correlated with the time to the trough plasma concentrations of paracetamol and levodopa. 4. There was excellent agreement between the plasma concentration-time curves of levodopa and paracetamol, i.e. time to initial peak, r = 0.946, P less than 0.001; time to trough concentration r = 0.943, P less than 0.01; time to second peak r = 0.974, P less than 0.001. 5. The results indicate that levodopa inhibits gastric emptying and thus influences its own absorption. Temporary inhibition of gastric emptying by levodopa (or a metabolite) is the cause of the multiple plasma peaks commonly observed following oral levodopa. 相似文献
42.
老年肺炎患者免疫及机体的反应能力差,起病缓慢隐匿,缺乏典型症状与体征,并发病及伴发病多,治疗反应差,病死率高,诊断和治疗时均应考虑这些特点。 相似文献
43.
John DellaCroce Jessica Laursen Ramesh S Ayyala 《Ophthalmic surgery, lasers & imaging》2007,38(6):503-504
The authors report the occurrence and clinical course of serous retinal detachment following glaucoma surgery in three patients. Serous detachment resolved in all patients spontaneously following treatment with oral and topical steroids. 相似文献
44.
The major limitation in adult-to-adult living donor liver transplantation (LDLT) is an adequate graft size with special regard to the safety of the donor. Only 20% of the evaluated donors are suitable to donate the right liver, depending mainly on the critical remnant liver volume. We report 2 cases of adult-to-adult LDLT using dual grafts. In the first case we implanted a left lateral lobe together with a left lobe; in the second case we used a left lateral and a right lobe. Dual graft LDLT solves the problem of graft-size insufficiency and avoids critical right lobectomy in the donor. This procedure can be safely performed and opens up the possibility of LDLT to even more families in the Western world. 相似文献
45.
Actin-free Gc globulin: a rapidly assessed biomarker of organ dysfunction in acute liver failure and cirrhosis. 总被引:2,自引:0,他引:2
Charalambos G Antoniades Philip A Berry Matthew Bruce Timothy J S Cross Andrew J Portal Munther J Hussain William Bernal Julia A Wendon Diego Vergani 《Liver transplantation》2007,13(9):1254-1261
Reductions in serum levels of Gc globulin, a hepatically synthesized component of the extracellular actin scavenger system responsible for complexing circulating actin and attenuating intravascular microthrombus formation, are associated with poor outcome in acute liver failure. Clinically applicable assays of the important actin-free fraction (Af-Gc) have not been available until now. We measured actin-free Gc globulin levels with a novel, rapid assay in 61 cases of acute liver failure (ALF) and in 91 patients with cirrhosis (40 of whom were clinically unstable with extrahepatic organ dysfunction), and studied associations with liver dysfunction, extrahepatic organ dysfunction, indices of disseminated coagulation, and outcome. Reductions in Af-Gc levels mirrored hepatic dysfunction and organ dysfunction in both groups, and discriminated patients with poor prognosis from those with good prognosis in the ALF cohort. Levels were lowest in patients with ALF (10% of control values), but levels were also markedly reduced in both unstable (28%) and stable (44%) patients with cirrhosis. Associations with markers of disseminated intravascular coagulation were seen in both groups, most notably in the cirrhosis cohort, supporting a pathophysiological role for reduced Af-Gc in the evolution of organ dysfunction. In acetaminophen-induced ALF, Af-Gc identified patients with poor prognosis as well as did the Acute Physiology and Chronic Health Evaluation (APACHE II) score (area under the receiver operating characteristic curve, 0.7), and in cirrhosis, Af-Gc was an independent predictor of mortality by multifactorial analysis. In conclusion, the importance of Af-Gc reductions in the development of multiple organ dysfunction in ALF and cirrhosis is highlighted, probably resulting from reduced hepatic production and peripheral exhaustion of this arm of the extracellular actin scavenger system. 相似文献
46.
47.
控制性降压在临床麻醉中的应用进展 总被引:6,自引:0,他引:6
控制性低血压是指在某些手术麻醉期间,用药物等方法降低血压,以达到减少手术野出血,便于手术操作的一种方法,通常采用血管扩张剂,钙通道阻断剂及麻醉来控制血压,现就这一领域的研究进展作一综述。 相似文献
48.
本文应用“冷沉淀”法制备纤维组织粘合剂。对纤维组织粘合剂中主要成份和含量进行了测定,并测定了主要理化性质,建立了动物实验模型,观察了实验兔对纤维粘合剂的反应。 相似文献
49.
大剂量甲基强的松龙冲击治疗急性脊髓损伤疗效分析 总被引:12,自引:0,他引:12
目的研究大剂量甲基强的松龙(MP)治疗急性脊髓损伤的临床效果.方法对87例急性脊髓损伤患者进行回顾性研究,根据伤后时间并按自愿选择用药原则分为应用MP治疗组(MP组,45例)和未应用MP治疗组(对照组,42例),以ASIA分级标准进行分级,并比较疗效和并发症.结果两组患者在治疗前后感觉及运动功能均有明显改善(P<0.05).但MP组的感觉及运动功能恢复均优于对照组(P<0.05).MP治疗组中24h治疗组(A组)与48h治疗组(B组)并发症发生率比较无显著性差异(P>0.05),而MP组与对照组比较并发症的发生率明显增加,有显著性差异(P<0.05).结论早期应用MP大剂量冲击治疗急性脊髓损伤是一项有效措施,但会显著增加患者治疗中并发症的发生率. 相似文献
50.
Nicole Y. L. Oei Bernet M. Elzinga Oliver T. Wolf Michiel B. de Ruiter Jessica S. Damoiseaux Joost P. A. Kuijer Dick J. Veltman Philip Scheltens Serge A. R. B. Rombouts 《Brain imaging and behavior》2007,1(1-2):31-41
Glucocorticoids (GCs, cortisol in human) are associated with impairments in declarative memory retrieval. Brain regions hypothesized
to mediate these effects are the hippocampus and prefrontal cortex (PFC). Our aim was to use fMRI in localizing the effects
of GCs during declarative memory retrieval. Therefore, we tested memory retrieval in 21 young healthy males in a randomized
placebo-controlled crossover design. Participants encoded word lists containing neutral and emotional words 1 h prior to ingestion
of 20 mg hydrocortisone. Memory retrieval was tested using an old/new recognition paradigm in a rapid event-related design.
It was found that hydrocortisone decreased brain activity in both the hippocampus and PFC during successful retrieval of neutral
words. These observations are consistent with previous animal and human studies suggesting that glucocorticoids modulate both
hippocampal and prefrontal brain regions that are crucially involved in memory processing.
Electronic Supplementary Material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献