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71.
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
72.
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
73.
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
74.
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
75.
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
76.
本文利用国产抗血小板膜糖蛋白单克隆抗体分别制备出抗人血小板膜糖蛋白(GPIb、GPⅡb及GPⅢa)的免疫金探针。以此探针检测了9例“刺参诱聚缺陷症”患者及2例血小板无力症患者血小板膜糖蛋白。结果表明“剌参诱聚缺陷症患者”其静息状态下血小板GPIb、GPⅡb正常,GPⅢa低于正常时照组(P<0.01)。经“剌参”刺激后,GPⅢa仍低于正常(P<O.01),而经ADP刺激后GPⅢa可恢复正常。血小板无力症患者其静息状态下GPIb正常,GPⅡb、GPⅢa、均低于正常(P<0.01)。经“刺参”、ADP刺激后GPⅢa、GPⅡb仍低于正常,(P<O.01)。 相似文献
77.
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
78.
79.
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
80.
In this study, large areas of goldfish telencephalon were ablated including rostral nucleus preopticus periventriculare (rNPP), and degenerating axons were traced by a modified Fink and Heimer procedure. The lesioning procedure ablated large regions of area dorsalis telencephali pars medialis, centralis, and dorsolateral complex; and completely removed area ventralis telencephali pars dorsalis, ventralis, and lateralis. In addition, the supracommissural nucleus and rNPP were lesioned specifically because both nuclei have been thought to be involved in courtship behavior and endocrine control of reproduction. This investigation demonstrated extensive fiber projections from telencephalic nuclei and/or rNPP to the hypothalamus. Lesioned telencephalon and/or rNPP projected bilaterally to nucleus preopticus and the suprachiasmatic nucleus and unilaterally to the following tuberal nuclei: nucleus anterior tuberis, and the lateral hypothalamic nucleus. A much larger fiber projection to the inferior lobe nuclei was also observed with a large contralateral as well as ipsilateral input. 相似文献