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41.
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
42.
Dawn Stacey RN MScN CON Annette M. O'Connor RN PhD † Cathy DeGrasse RN MScN ‡ Shailendra Verma MD FRCP § 《Health expectations》2003,6(1):3-18
Objective To develop and evaluate the effectiveness of a breast cancer prevention decision aid for women aged 50 and older at higher risk of breast cancer. Design Pre‐test–post‐test study using decision aid alone and in combination with counselling. Setting Breast Cancer Risk Assessment Clinic. Participants Twenty‐seven women aged 50–69 with 1.66% or higher 5‐year risk of breast cancer. Intervention Self‐administered breast cancer prevention decision aid. Main outcome measures Acceptability; decisional conflict; knowledge; realistic expectations; choice predisposition; intention to improve life‐style practices; psychological distress; and satisfaction with preparation for consultation. Results The decision aid alone, or in combination with counselling, decreased some dimensions of decisional conflict, increased knowledge (P < 0.01), and created more realistic expectations (P < 0.01). The aid in combination with counselling, significantly reduced decisional conflict (P < 0.01) and psychological distress (P < 0.02), helped the uncertain become certain (P < 0.02), and increased intentions to adopt healthier life‐style practices (P < 0.03). Women rated the aid as acceptable, and both women and practitioners were satisfied with the effect it had on the counselling session. Conclusion The decision aid shows promise as a useful decision support tool. Further research should compare the effect of the decision aid in combination with counselling to counselling alone. 相似文献
43.
In order to compare an acceleromyograph (TOF-GuardTM ) with a mechanomyograph (Grass FT03), the dose–response relationship of rocuronium was simultaneously determined in both arms of 15 children aged 3–11 years during anaesthesia with thiopentone, alfentanil and nitrous oxide. Three subgroups of five children received rocuronium 120, 180 or 240 μg.kg−1 randomly. The effective doses to produce 50% and 95% depression of the first twitch of the train-of-four determined by acceleromyography were 206 and 337 μg.kg−1 , respectively, while these values determined by mechanomyography were 151 and 331 μg.kg−1 , respectively. The dose–response curve obtained by acceleromyography was steeper and shifted to the right compared with that obtained by mechanomyography (p < 0.0001). The difference between the effective dose producing 50% twitch depression determined by the two devices was highly significant (p < 0.0001). In 13 out of 15 children, the acceleromyograph control train-of-four ratio was significantly greater than unity. Although there was a good correlation ( r = 0.85) between simultaneous pairs of measurements of neuromuscular block, the acceleromyograph exhibited a bias of −25% relative to the mechanomyograph with wide limits of agreement (−62 to +12%). We conclude that acceleromyographic and mechanomyographic measurements should not be used interchangeably when determining the potency of muscle relaxants. 相似文献
44.
An epidural abscess due to resistant Staphylococcus aureus following epidural catheterisation 总被引:1,自引:0,他引:1
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
45.
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
46.
We have developed a computerized neuromuscular monitoring system (NMMS) using commercially available subsystems, i.e., computer
equipment, clinical nerve stimulator, force transducer, and strip-chart recorder. This NMMS was developed for acquisition
and analysis of data for research and teaching purposes. Computer analysis of the muscle response to stimulation allows graphic
and numeric presentation of the twitch response and calculated ratios. Since the system can store and recall data, research
data can be accessed for analysis and graphic presentation. An IBM PC/AT computer is used as the central controller and data
processor. The computer controls timing of the nerve stimulator output, initiates data acquisition, and adjusts the paper
speed of the strip chart recorder. The data processing functions include establishing control response values (when no neuromuscular
blockade is present), displaying force versus time and calculated data graphically and numerically, and storing these data
for further analysis. The general purpose nature of the computer and strip chart recording equipment allow modification of
the system primarily by changes in software. For example, new patterns of nerve stimulation, such as the posttetanic count,
can be programmed into the computer system along with appropriate data display and analysis routines. The NMMS has functioned
well in the operating room environment. We have had no episodes of electrocautery interference with the computer functions.
The automated features have enhanced the utility of the NMMS. The prime advantages of this system are (1) the ability to customize
its features by altering its controlling programs, (2) the ready availability of the hardware and software, (3) the general
purpose nature of the system, so that it is not limited to this one application, and (4) the adaptable nature of the system. 相似文献
47.
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49.
七种常见舌苔的细胞化学计量诊断研究 总被引:20,自引:0,他引:20
以117例常见舌苔上皮细胞内LDH、MDH、G-6-PDH、ACP、ANAE、-SH、RNA七种生物大分子物质的定量检测为基础,运用多元逐步回归方法建立正常薄白、虚寒薄白及白厚、薄黄、黄厚、花剥、光剥种舌苔的计量诊断模型,经临床回代检验,其敏感性、特异性、准确度、可用度分别为93.2%、81.4%、87.2%和75.7%。 相似文献
50.
Monoclonal antibodies to intermediate filament proteins: Diagnostic specificity in orbital pathology
Thomas D. Lindquist M.D. Ph.D. James C. Orcutt M.D. Ph.D. Allen M. Gown M.D. 《Survey of ophthalmology》1988,32(6):421-426
Intermediate filaments derived from different cell types are antigenically distinct. Monoclonal antibodies to human intermediate filament proteins can, therefore, be used as tissue-specific reagents capable of distinguishing cell type in poorly differentiated neoplasms. We report a case demonstrating the specificity of antiintermediate filament protein antibodies in establishing a difficult orbital diagnosis of esthesioneuroblastoma. 相似文献