共查询到20条相似文献,搜索用时 15 毫秒
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C Sakuramoto 《Canadian Metallurgical Quarterly》1997,46(8):1130-1133
We evaluated the insertion characteristics and complications of a new spinal needle 26-gauge Atraucan (group A) compared with 27-gauge Whitacre (group W) in 100 patients undergoing orthopedic surgeries of the lower extremities. Spinal anesthesia was performed in the lateral decubitus position and 0.40-0.5% tetracaine 1.6-2.5 ml was injected through the L 3/4 or L 4/5 interspace. The tactile appreciation of dural presentation with the needle (dural click) was higher in group W (89.8%) than in group A (42.6%) which the back flow of cerebrospinal fluid was not recognized within three punctures was in 2 cases (4%) in group A and in 1 case (2%) in group W. In these 3 cases, spinal anesthesia was performed easily using 25-gauge Whitacre. In group A, the spinal needle could be inserted without using an introducer in 35 cases (70%). The incidence of the postoperative headache or back pain was low and postdural puncture headache (PDPH) did not occur in both groups. We conclude that 26-gauge Atraucan can be handled easily and useful for preventing PDPH. 相似文献
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A 17-residue peptide containing the caulimovirus-related "zinc finger' was prepared by solid-phase peptide synthesis. Fluorescence measurements showed that the tryptophan quantum yield was Zn(2+)-dependent, allowing a 1:1 a stoichiometry for the complex to be determined. The structure of the peptide was characterized using circular dichroic spectroscopy, which indicates that the peptide exhibits a random coiled conformation in the absence of zinc but appears to form an ordered structure in the presence of zinc. 相似文献
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Q Hogan 《Canadian Metallurgical Quarterly》1998,23(4):340-3; discussion 384-7
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Leukotriene A4 (LTA4) hydrolase is a bifunctional zinc metalloenzyme which catalyzes the final step in the biosynthesis of the proinflammatory leukotriene B4 and which also possesses a peptidase activity. From sequence comparisons with aminopeptidases, a tyrosine at position 383 in LTA4 hydrolase has been suggested as a possible catalytic amino acid. To explore the potential role of this amino acid in catalysis, we replaced the tyrosine residue with phenylalanine, histidine or glutamine residues by site-directed mutagenesis. The mutated cDNAs were expressed in Escherichia coli and the resulting recombinant proteins, named [Y383F]LTA4 hydrolase, [Y383H]LTA4 hydrolase and [Y383Q]LTA4 hydrolase, were purified to homogeneity to allow assays of both the epoxide hydrolase activity, i.e. the conversion of LTA4 into leukotriene B4, and the peptidase activity. None of the mutated proteins exhibited significant peptidase activities, all of them showing activities less than 0.3% that of the wild-type enzyme. The epoxide hydrolase activity was not affected to the same degree and corresponded to 11, 16 and 17% that of the unmutated enzyme for [Y383F]LTA4 hydrolase, [Y383H]LTA4 hydrolase and [Y383Q]LTA4 hydrolase, respectively. Kinetic analysis was performed with the mutant [Y383Q]LTA4 hydrolase, which revealed an approximately 10-fold increase in Km for leukotriene A4 compared to that for the unmutated enzyme. At high concentrations of substrate, the difference in enzyme velocity was only moderate, with Vmax values of 600 nmol.mg-1.min-1 and 1000 nmol.mg-1.min-1 for [Y383Q]LTA4 hydrolase and the wild-type enzyme, respectively. No such effect of substrate concentration could be observed on the peptidase activity. As a positive control, we exchanged a glycine residue in position 386 for an alanine residue, and the recombinant protein, [G386A]LTA4 hydrolase retained 19% and 77% of the peptidase and epoxide hydrolase activities, respectively. The results from this study are consistent with a role for Tyr383 in the peptidase reaction of LTA4 hydrolase, where it may act as a proton donor in a general base mechanism. However, our data do not allow a similar interpretation for the mechanism involved in the hydrolysis of LTA4 into LTB4. 相似文献
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SS Liu 《Canadian Metallurgical Quarterly》1998,23(4):344-6; discussion 384-7
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SS Liu RA Stevens J Vasquez TC Kao T Sheikh M Aasen K Frey 《Canadian Metallurgical Quarterly》1997,84(4):780-783
Epinephrine test doses may be administered during combined spinal-epidural anesthesia to determine intravascular placement of epidural catheters. This study was designed to determine systolic blood pressure (SBP) and heart rate (HR) responses to intravenous injection of epinephrine (15 microg) during spinal anesthesia. Twelve volunteers received three spinal anesthetics (lidocaine 100 mg, tetracaine 15 mg, and bupivacaine 15 mg) in a randomized, double blind, cross-over fashion. Epinephrine was administered prior to spinal anesthesia (control), 30 min after injection of spinal anesthesia, and at regression of sensory block to T-10. SBP was measured with a radial arterial catheter and HR with an electrocardiogram. Positive responses were defined as peak increase in SBP > or = 15 mm Hg or HR > or = 20 bpm after injection of epinephrine. Compared with control, peak SBP responses decreased by a mean of 12 mm Hg during spinal anesthesia with tetracaine and bupivacaine (P < 0.05). Peak HR responses decreased by 11 bpm during all three spinal anesthetics (P < 0.05). Incidences of detection of intravenous injection by positive SBP and HR responses ranged from 50% to 100% and were not significantly affected by spinal anesthesia. Spinal anesthesia reduces hemodynamic responses to intravenous epinephrine injection but is unlikely to reduce detection by positive SBP and HR criteria. 相似文献
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In this prospective study we investigated the efficacy of microcatheter spinal anaesthesia in comparison with a combined spinal-epidural technique in trauma patients. METHODS: After institutional approval 60 patients undergoing urgent lower-limb surgery randomly received either CSA (22 G Sprotte needle, 28 G nylon catheter) in group 1 or CSE (18 G Tuohy needle, 22 G epidural catheter and 25 G pencil-point needle) in group 2. An initial subarachnoid bolus of 2 ml of plain bupivacaine 0.5% was injected in both groups. Difficulties with the lumbar puncture or catheter insertion, the time required for performance of either technique and the onset of analgesia at T12 were documented. If analgesia did not reach T12 within 20 min, supplemental bupivacaine was injected either intrathecally or epidurally up to a maximum of 5 ml in the CSA group or 16 ml in the CSE group. RESULTS: The number of lumbar punctures (CSA: n = 1.8 +/- 1.5; CSE: n = 2.6 +/- 1.8; P = 0.05) and the incidence of technical problems (CSA: 13%, CSE: 47%; P = 0.012) was higher in the CSE group. In contrast to CSA, performance of CSE was more time consuming (CSA: 8 +/- 3 min, CSE: 15 +/- 8 min; P = 0.0003), and the total dose of local anaesthetics was higher in the CSE group (CSA: 3.2 +/- 1 ml, CSE: 9.7 +/- 5 ml; P < 0.0001). CONCLUSIONS: Because of the higher incidence of technical problems, more time was required for the performance of CSE. As a consequence, microcatheter CSA might be preferred over CSE in trauma patients. 相似文献
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J Butterworth 《Canadian Metallurgical Quarterly》1998,23(4):370-3; discussion 384-7
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D Fletcher K Samii A Bénichou D Fillette A Bertin M Germond D Laverdisse JM Mascaro E Normand Y Piroelle 《Canadian Metallurgical Quarterly》1995,43(5):497-499
The goal of this randomized, double blind and multicentric study was to compare the effects of midazolam (M) and placebo (P) administered by titration before puncture for spinal anaesthesia on the comfort of 211 patients scheduled for elective surgery after oral premedication with hydroxyzine. The administered dose of midazolam was 3.4 +/- 1.3 mg (mean +/- SD). Anxiety was nil in 92% of the patients of the M group and in 64% of the patients of the P group (p < 0.001) and memorization of the pain of the puncture was reported in 34% of the patients of the M group and in 66% of the patients of the P group (p < 0.001). However cooperation of the patient and easiness of the puncture were similar in both groups. In conclusion titrated sedation with midazolam before puncture for spinal anaesthesia increases the comfort of the patient. 相似文献
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We present the case of a parturient with moyamoya disease admitted to the hospital for elective cesarean section. Combined spinal and epidural technique was chosen because it allows better analgesia than epidural anesthesia and more hemodynamic stability than either general or spinal anesthesia. Ropivacaine was the local anesthetic of choice for the epidural portion because of the wide sensory-motor dissociation, thus preserving adequate respiration in the case of a high block. 相似文献
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The junction between double-lumen endotracheal tube (DLT) and anaesthetic circuit is of crucial importance to modern anaesthesiological management in thoracic surgery. We present a connector which allows for all the essential procedures, such as clinical control of DLT position, use of fiberoptic bronchoscope (FOB) to control or correct DLT position, application of differential lung ventilation patterns or simple suction manoeuvres by easy handling, minimal interference, and avoidance of disconnection or clamping. 相似文献