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101.
BACKGROUND: High-dose transarterial (TA) technique results in high effectiveness of the axillary block. The technique is fast and simple, but does not produce a satisfactory success rate when using the manufacturer's recommended dose of mepivacaine. The multiple nerve stimulation (MNS) technique requires more time and experience. This double-blind study compared effectiveness, safety and the time used to obtain an effective analgesia in 101 patients, having an axillary block by either TA or MNS techniques. METHODS: Mepivacaine with adrenaline (MEPA), 850 mg, was used for the initial block. Five millilitres of 1% solution was injected subcutaneously. In the TA group, 20 mL of 2% solution was injected deep to, and 20 mL superficial to the axillary artery. In the MNS group, four terminal motor nerves were electrolocated in the axilla, and injected with 10 mL each. Analgesia was assessed every 10 min and, when needed, supplemented after 30 min. The block was effective when analgesia was present in all sensory nerve areas distal to the elbow. RESULTS: The MNS group required median 11 min for block performance compared with 8 min for the TA group (P < 0.001). Latency of the initial block was shorter and the frequency of supplemental analgesia lower in the MNS group (median 10 min and 6%) than in the TA group (30 min and 36%, respectively), P < 0.001. All incomplete blocks were successfully supplemented. However, the total time to obtain an effective block was shorter in the MNS group (23 min) than in the TA group (37 min), P < 0.001. Two patients in each group had signs and symptoms of systemic toxicity, the most serious being atrial fibrillation and temporary loss of consciousness in a cardiovascularly medicated patient. The local adverse effects (intravascular injections and haematomas) were fewer in the MNS group, P < 0.001. CONCLUSION: The MNS technique of axillary block by four injections of 10 mL of 2% MEPA produces faster and more extensive block than the TA technique by two injections of 20 mL. Therefore, the MNS technique requires fewer supplementary blocks and results in faster patient readiness for surgery. However, high doses of MEPA may result in dangerous systemic toxic reactions.  相似文献   
102.
In this prospective randomised study, pruritus and pain were evaluated in patients undergoing abdominal surgery during which epidural fentanyl was administered. All patients had an epidural catheter inserted at the time of surgery. Epidural fentanyl 100 micrograms was administered intra-operatively and infused at a concentration of 2 micrograms.ml-1 for 48 h postoperatively. All patients received a standard anaesthetic and, in addition, the study group had a 20 mg bolus of tenoxicam intravenously, intra-operatively. Patients receiving tenoxicam demonstrated significantly lower pruritus and pain scores at 30 min, 2, 4, 8 and 24 h postoperatively as well as reduced pethidine requirements for breakthrough pain in the first 24 h. In conclusion, tenoxicam 20 mg significantly reduces the incidence and severity of postoperative pruritus in patients who received peri-operative epidural fentanyl. In addition, it significantly reduces pain and further analgesic requirements postoperatively.  相似文献   
103.
Summary We found that a receptor ligands differentially regulated the acetylcholine (ACh) neurotransmission in the rat brain. Acute administration of (+)-N-allylnormetazocine [(+)-SKF-10,047], a prototype 1 receptor ligand, and 1,3-di(2-tolyl)guanidine (DTG), a non-specific receptor ligand, increased the extracellular ACh level in the rat hippocampus. This increase of hippocampal extracellular ACh level elicited by (+)-SKF-10,047 was more potent than that elicited by DTG. On the other hand, the striatal extracellular ACh level was slightly affected by (+)-SKF-10,047. In addition, DTG did not affect the striatal extracellular ACh level. Our previous studies have shown that both (+)-SKF-10,047 and DTG increased the extracellular ACh level in the rat frontal cortex. Taking all these data into consideration, the regulation of ACh neurotransmission by receptor ligands are different depending upon the brain region.  相似文献   
104.
Summary Blood flow heterogeneity in normal myocardium may be caused by heterogeneous metabolic demand. We studied, from 80 tissue samples of the left ventricle (LV) of eight anesthetised, open-chest dogs (with prior -blockade (metoprolol) in four dogs), the radioactivity of201Thalliumchloride (201Tl), an indicator of blood flow, and of the fatty acid131-Iodine-heptadecanoic acid (131I-HDA), an indicator of metabolic demand, 3 min after intravenous injection. Global LV uptake (in percent of injected dose ×10–2, per g tissue; mean ±SD) was 4.94±0.71 for201Tl and 4.48±0.58 for131I-HDA in the dogs without -blockade, and 2.08±0.26 and 1.69±0.20, respectively, in dogs with -blockade (p<0.05). Beta-blockade thus decreased the fraction of cardiac output delivered to the LV, concurrently with a decreased heart rate and arterial blood pressure (p<0.05) and, thus, global metabolic demand and fatty acid uptake. Regional radioactivities per gram were normalized for mean LV radioactivities and heterogeneity was expressed as the coefficient of variation (CV). For pooled data (n=320) in dogs without -blockade, regional201Tl and131I-HDA radioactivities varied from a factor of 0.1 to 1.6 and 0.3 to 1.8 of mean radioactivities, with a CV of 22.9 and 19.4%, respectively, and correlated (r=0.77, p<0.005). For pooled data (n=320) in dogs with -blockade, regional201Tl and131I-HDA radioactivities varied from a factor of 0.2 to 1.5 and 0.2 to 1.6 of mean radioactivity and CV was 23.6% and 24.8%, respectively: r=0.92 (p<0.005). The endo/epi ratio for both radioactivities exceeded unity in each dog. In normal myocardium, blood flow and fatty acid uptake are thus heterogeneous, both transmurally and circumferentially, and matched, concomitantly with coupling of global blood flow to global metabolic demand and fatty acid uptake. This supports the idea that heterogeneous myocardial O2 supply reflects heterogeneous metabolic demand.  相似文献   
105.
Spinal and epidural anaesthesia were compared in 65 patients undergoing hip arthroplasty, with regard to the degree of sensory and motor blockade, cardiovascular effects, operating conditions, the dose of propofol required to produce satisfactory hypnosis, and complications. Epidural anaesthesia was successful in 30 patients using an initial dose of 15 ml of 0.5% bupivacaine, and spinal anaesthesia in 32 patients, using 4 ml 0.5% isobaric bupivacaine. The two techniques were similar with regard to the level of sensory blockade (T8), degree of hypotension and perioperative haemorrhage. Differences occurred in the degree of motor blockade (mean Bromage score of 1 in the spinal group vs 3.86 in the epidural group) (P less than 0.05), time to achieve maximal cephalad spread (13 min in the spinal group vs 21 min in the epidural group) (P less than 0.05) and the dose of propofol required to produce adequate hypnosis (1.95 mg.kg-1.hr-1 in the spinal group vs 2.89 mg.kg-1.hr-1 in the epidural group) (P less than 0.05). Only seven patients required urethral catheterization in this spinal group compared with 14 in the epidural group (P less than 0.05). Spinal anaesthesia also proved advantageous by providing better operating conditions for the surgeon, with a lower incidence of patient movement.  相似文献   
106.
Three cases are reported where continuous lumbosacral block was performed using a catheter through an epidural needle technique. Good unilateral lower limb surgical anaesthesia was achieved in all three cases with successful blockade of the lumbar and sacral plexuses. A 17-gauge Tuohy needle was positioned between the transverse processes of L4 and L5 and an epidural catheter inserted into the space between the quadratus lumborum and psoas muscles. Forty to seventy millilitres of local anaesthetic were injected and resulted in good surgical anaesthesia within 12-20 min. Radiographic studies in these patients confirmed placement of the catheter in close proximity to the lumbosacral plexus. Experience in a further 12 cases is also reported. There were no side-effects. The technique is successful and is recommended when unilateral lower limb anaesthetic is required and when spinal and epidural anaesthesia are contraindicated.  相似文献   
107.
The role of exposure to ambient air pollution has been a topic of interest as a potential risk factor for respiratory symptoms and asthma. We expected that the prevalence rates would vary in Norway between the capital, Oslo, the mountainous area Hallingdal and the industrial area Odda. Surveys were conducted in school children, aged 6-16 years, in; Oslo (n=2577), Hallingdal (n=1177) and Odda (n=831). The parent-reported prevalence of wheeze in past year was almost similar in Oslo (13. 1 (95% CI 11. 7-14. 5)) and Upper Hallingdal (14. 2 (13. 1–15. 3)), but lower in Odda (9. 0 (7. 0–11. 0)). The findings for severe respiratory symptoms were almost equal. The age patters within each area differed. The risk of wheeze ever (p < 0.001) and wheeze in past year (p=0.04) decreased with increasing age in Odda, while there was an increase in the risk of exercise induced wheeze in Oslo (p=0.02) and Hallingdal (p < 0.001). The lifetime prevalence of asthma was lowest in Odda (5. 4 (3. 8–7. 0)) compared to Oslo (9. 4 (8. 2–10. 6)) and Hallingdal (8. 5 (6. 8–10. 2)). There was a positive association between physical activity and wheeze in past year. The results do not support the hypothesis that respiratory morbidity is more common in urban than rural areas, age and physical activity can influence the prevalence rates of respiratory symptoms in school children.  相似文献   
108.
阿霉素脂质体淋巴管灌注的靶向效果   总被引:2,自引:0,他引:2  
目的:探讨阿霉素脂质体经淋巴管灌注后的体内动力学过程以及靶向效果。方法:将60只家兔随机分为阿霉素脂质体和阿霉素水溶液两组,从家兔足背淋巴管给药,采用高效液相色谱(HPLC)法检测给药后各时点外周血及腹膜后淋巴结中阿霉素药物浓度,并将摘取的淋巴结作病理检查。结果:水溶液组腹膜后淋巴结阿霉素峰浓度(Cmax)为46.81μg/g,药时曲线下面积(AUC)为31.86μg/dayg-1;而脂质体组阿霉素峰浓度为91.23μg/g,AUC为138.34μg/dayg-1。在外周血中脂质体组的峰浓度只有水溶液组的1/5。淋巴结病理检查结果表明,脂质体组的水肿、坏死、纤维化较水溶液组明显,而心肌病理反应较轻或不存在。结论:脂质体对淋巴结具有高度靶向性,阿霉素脂质体淋巴管灌注有可能成为治疗淋巴结转移的有效且副作用少的新方法。  相似文献   
109.
Purposes: The study evaluates prognostic factors for dissemination and survival in patients with local or regional recurrence of breast cancer. Furthermore, the aim was to define subgroups of patients at different risk of developing metastases in specific anatomical sites. Patients and methods: The study included 140 patients with isolated local or regional node recurrence, who entered a prospective study for staging of patients with first recurrence of breast cancer in the period 1983–85. The primary treatment was a simple mastectomy; node positive patients received adjuvant radiotherapy and chemotherapy or tamoxifen.If possible, the locoregional recurrence was treated with surgery and/or radiotherapy, otherwise by systemic therapy. Results: Median follow up was 10.4 years; 78 patients developed distant metastases (soft tissue, 32%; bone, 45%; viscera 40%). Median time to dissemination was 4.4 years, and the ten year dissemination rate was 72%. Median time to dissemination was 3.7 years for patients with recurrence in the regional nodes compared to 6.5 years for patients with chest wall recurrence only, p = 0.05. No specific time sequence (temporal pattern) was observed in the anatomical distribution of metastases, and the anatomical site of recurrence could not be predicted by any of the prognostic factors. At follow up, 93 patients had died. The median survival was 5.6 years and 30% were alive after 10 years. Forty-three of the 99 patients who received local therapy only did not develop metastases. Fifteen of these patients died without evidence of metastatic disease while 28 patients were still alive without distant recurrence after a median follow up time of 9.3 years (range, 6.5–11.9 years). Level of LDH and the number of positive regional nodes (NPOS) at primary diagnosis were significant independent prognostic factors for survival after recurrence. Conclusions: Approximately one third of the patients receiving local treatment only, were alive and without distant metastases up to ten years after locoregional recurrence, indicating that there is a subset of patients which may be long term survivors after local treatment only (surgery or radiotherapy). The duration of survival can be estimated by LDH and NPOS, but the model needs validation in a separate data set before clinical use.  相似文献   
110.
鼻窦炎患者鼻窦骨结构变异和鼻窦粘膜异常的CT扫描分析   总被引:2,自引:0,他引:2  
对109例临床疑为鼻窦炎患者的CT冠状扫描结果进行了分析,鼻窦粘膜异常改变者93例(85.3%),16例粘膜呈正常影像(14.7%),93例鼻窦粘膜异常改变者中,发现鼻窦骨结构变异60例(64.5%)。通过对鼻窦骨结构变异和鼻窦炎情况的观察分析,认为鼻窦骨结构变异可能是鼻窦炎致病因素之一。鼻窦粘膜异常以前组筛窦和上颌窦发生率最高,同时伴有窦口鼻道复合体粘膜异常,支持了鼻窦口引流障碍可以继发鼻窦炎的观点。作者认为采用鼻窦CT冠状扫描对判断鼻窦炎的病因和临床诊断具有重要意义。  相似文献   
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