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31.
Flow dynamics through spinal needles   总被引:2,自引:0,他引:2  
We examined the flow pattern produced when liquid dye was actively injected into a fluid medium at various flows through five different commonly used spinal needles. At all flows, the Whitacre-type needles produced a directional stream exiting at an angle from the longitudinal axis. At intermediate rates the stream developed tracks which disappeared at faster rates. The Quincke needle always produced an undeviated stream of dye and did not form tracks at any flow rate. When a perspex plate (representing the spinal cord) was interposed in front of the needle, the dispersion of dye was always unidirectional from the Whitacre needle and bidirectional from the Quincke needle. The dye adhered to the surface of the plate as a concentrated film at slow rates and at faster rates it dispersed turbulently for both types of needle.  相似文献   
32.
We report a case of abscess formation after epidural analgesia, a rare complication that developed in our patient 13 days after placement of a thoracic epidural catheter for patient controlled analgesia. Culture of the pus grew methicillin-resistant Staphylococcus aureus . Although early diagnosis and rapid management have been reported to yield a satisfactory outcome, the case we describe ended in severe sequelae.  相似文献   
33.
The effect of subhypnotic doses of propofol on intrathecal morphine-induced pruritus was studied in a prospective, randomly allocated, double-blind controlled trial. Fifty-eight women undergoing elective lower segment Caesarean section for a singleton fetus received spinal anaesthesia with 2.5 ml hyperbaric 0.5% bupivacaine and 0.2 mg of preservative-free morphine. They then received propofol 1 ml (10 mg) or Intralipid 1 ml (control group) intravenously after delivery. Pruritus was assessed using a five-point verbal rating scale at hourly intervals for 8 h. A second dose of their allocated treatment drug was administered at the first recording of significant pruritus. The pruritus score was reassessed after 5 min and the treatment was repeated if pruritus remained. There were no differences between the groups in the onset of pruritus or its successful treatment. No adverse side-effects were associated with this dose of propofol. There were no differences in the incidence of post-operative nausea and vomiting between the two groups. Subhypnotic propofol is not an effective treatment for intrathecal morphine-induced pruritus in women following Caesarean section.  相似文献   
34.
喉的解剖较复杂,从CT图象上分辨更为困难。木文通过比较尸体喉区的断层解剖标本,从4个不同的平面,描述了喉区各结构形态大小的变化,并讨论其分布特征,这将有助于临床CT的诊断。  相似文献   
35.
Long-term clinical and functional outcomes for patients undergoing foot and ankle amputations are not well documented. We attempted to document long-term outcomes for patients who required lower extremity amputations as a result of wounds suffered during wartime. For this study, 27 Iranian soldiers who had wounds requiring amputation of the foot and ankle were selected for follow-up. The participants' wartime medical records were reviewed, a clinical examination was performed, and each participant completed a questionnaire. Postamputation follow-up averaged 17.5 years. The most prevalent (66.6%) cause of injury was a land mine. The prevalences of different clinical symptoms reported by the amputees at the time of the last follow-up were as follows: 11 (40.7%) with phantom sensation, 6 (22.2%) with phantom pain, 12 (44.4%) with stump pain, 12 (44.4%) with back pain, 9 (33.3%) with contralateral knee pain, and 4 (14.8%) with ipsilateral knee pain; 20 (74%) reported treatment for psychological conditions. In regard to social conditions, 13 (48.1) were currently employed, or had been employed, for a number of years after the amputation; 26 (96%) had children, and all of the patients were married. The results of this observational study indicate that individuals have significant long-term pain and discomfort after war-related lower extremity amputation. Although all 27 (100%) of the amputees were able to maintain satisfactory family functioning, only 13 (48.1%) of the study participants were able to remain productively employed after undergoing amputation, and 20 (74%) reported long-term psychological problems in addition to their physical pain.  相似文献   
36.
37.
目的 探索单光子发射计算机断层扫描(SPECF)在脑外伤评估及预后方面的价值的依据。方法 28例中、重度颅脑损伤患者分别于伤后3天、10天及3~4周接受SPECF、CT检查及临床评定。3个月后所有患者行脑外伤综合征的临床测试,对首检SPECF显像阳性者复查SPECF,分析首检SPECF显像阳性者与损伤程度的关系,动态观察SPECF显像与预后的关系。结果 SPECF显像阳性与脑损伤程度有关,首检SPECF显像阳性提示预后良好,复查SPECF显像阳性提示多出现脑外伤综合征。对幕上损伤患者表现的小脑症状、体征可以做出合理的解释。结论 在中至重度颅脑损伤后SPECF显像与CT扫描比较更敏感,脑SPECF具有无创性、功能性及灵敏性高等特点,是脑外伤后功能评估、预后判断及临床研究的可靠方法。  相似文献   
38.
The majority of foot and ankle operations are performed on an outpatient basis and often under some form of regional anesthesia. In this prospective, randomized study of 51 patients undergoing elective unilateral forefoot procedures, we compared 2 different anesthetic techniques: the peripheral foot blockade and the popliteal sciatic nerve block. Variables assessed included the quality of surgical anesthesia, postoperative analgesia, and the incidence of postoperative complications. The anesthesia was classified as effective if it was the sole anesthetic technique for the forefoot surgery. We found successful results in both groups: 92% in the foot block group and 96% in the popliteal block group. Analysis of time required to perform the anesthetic procedure showed a significant difference between the 2 groups, with foot block being considerably faster (14.3 minutes vs 19.2 minutes for popliteal block) (P = .0078). Foot block patients demonstrated 10.96 hours of analgesia, whereas popliteal block patients exhibited 14.32 hours (P = .132). With a mean follow-up of 5.7 months, we did not find anesthesia-related complications in any of the patients. Both techniques showed a high level of safety and efficacy, with no significant difference detected between them. Our patients showed a high rate of satisfaction with both procedures (96% for foot block patients and 96.1% for popliteal block patients) and reported a good discharge disposition. These data show that both procedures are safe and effective anesthetic techniques and well suited to forefoot ambulatory surgery.  相似文献   
39.
跨越式发展是经济发展相对落后地区在借鉴和吸收先进国家和地区成功经验和优秀成果的基础上 ,通过技术和生产力的跨越、管理和制度的创新、产业结构的优化升级、经济运行质量的提升、速度和效益的并进 ,不平衡推进和超常规增长 ,最终实现经济整体跃升的一种新的发展模式。在国家宏观政策和市场机制的双重作用下 ,充分利用各种有利条件 ,努力实现区域经济跨越式发展已成为西部地区的必然选择。积极推进区域制度创新、技术创新和文化创新 ,构建西部区域经济跨越式发展的动力系统 ,既是西部区域经济跨越式发展的必由之路 ,也是西部地区当前面临的主要任务。在路径选择上必须把发挥比较优势和发挥后发优势有机结合起来 ,使二者相得益彰 ,从而走出一条具有西部特色的跨越式发展之路。  相似文献   
40.
解剖因素致单纯鼻源性头痛的鼻内镜手术   总被引:2,自引:0,他引:2  
目的 :探讨鼻内镜手术治疗解剖因素致单纯鼻源性头痛的方法和疗效。方法 :鼻内镜下切除或矫正鼻腔鼻窦区异常解剖结构。结果 :单一因素中鼻丘气房肥大 ,泡性中、上鼻甲及中隔偏曲分别为 7例、10例、12例 ,术后治愈率达 71.4 3%、6 0 .0 0 %、6 6 .6 7% ,合计治愈率达 6 5 .5 2 %。多因素者 4 4例 ,术后治愈率达38.6 4% ,与单一因素差异有显著性 (P <0 .0 2 5 )。患者治疗有效率达 10 0 %。结论 :鼻内镜手术是治疗解剖因素致单纯鼻源性头痛的有效方法之一 ,单一因素者疗效更佳。  相似文献   
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