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991.
目的将微波辅助提取新技术应用于茯苓水溶性多糖的提取,寻求最佳提取工艺。方法采用均匀优化设计试验条件,以苯酚-硫酸法测定样品中多糖含量。对超声辅助提取和传统水提法比较,并对水解前后的微波提取多糖衍生物用毛细管电泳检测。结果最佳提取条件:时间为18min;固液比为1:50;微波占空比42%,此时提取率为2.792%。优于传统。结论微波辅助提取速度更快、提取效率更高;毛细管电泳检测表明微波提取茯苓多糖过程合理,能得到较理想的提取物。 相似文献
992.
Carl Ganter 《Magnetic resonance in medicine》2004,52(2):368-375
A previously developed eigenvector formalism is adapted to off-resonance in the transient response of quasiperiodic steady-state free precession (SSFP) sequences, including TrueFISP as a special case. The effective relaxation rates for essentially parallel and perpendicular deviations from the steady state are determined analytically in leading order perturbation theory. The latter are a known cause of oscillatory artifacts and therefore constitute the main target of a variety of preparation techniques. In addition, the former also play a dominating role in applications such as inversion recovery (IR) TrueFISP, which intentionally measure far away from the equilibrium. For both components, the approach toward equilibrium turns out to depend sensitively on field inhomogeneities, especially for smaller ratios of T2/T1. For the perpendicular deviations, the calculations show that--except very close to banding artifacts, where the steady-state signal is almost zero--field inhomogeneities additionally increase their effective relaxation rate almost as much as in the free induction decay (FID). The analytical results are tested against numerical simulation and MR measurements. 相似文献
993.
Magnetization prepared segmented acquisition requires a view order that maximizes signal contrast during the acquisition of the central portion of k-space. Steady state free precession (SSFP) acquisition further requires a view order that minimizes changes in phase-encoding gradients from one repetition to the next in order to minimize eddy current artifacts. In this article, optimal view ordering schemes satisfying these two requirements are formulated and applied to inversion prepared 3D SSFP contrast-enhanced MR angiography (MRA). Experiments on phantoms and pigs demonstrated improved background suppression and reduced image artifacts. 相似文献
994.
J Dissemond D Haberer T Franckson U Hillen 《Journal of the European Academy of Dermatology and Venereology》2004,18(5):611-613
The Van der Woude syndrome is a rare autosomal dominant developmental malformation usually associated with bilateral lower lip pits. These congenital lip pits appear clinically as a malformation in the vermilion border of the lip, with or without excretion. As a genetic defect has been identified as a microdeletion of chromosome bands 1q32-q41, genetic counselling of patients may be considered. A nonsense mutation in the interferon regulatory factor-6 (IRF-6) is discussed as a pathogenic relevant factor. Therapeutic intervention is generally not necessary, although surgical excision is especially indicated in patients with recurrent inflammation. Physicians should be aware of the Van der Woude syndrome because it has been reported to be associated with a variety of malformations or other congenital disorders. 相似文献
995.
Marjolein Gysels Rhidian Hughes Fiona Aspinal Julia M Addington-Hall Irene J Higginson 《International journal for quality in health care》2004,16(5):375-381
OBJECTIVE: To investigate the opinions of stakeholders (service commissioners and providers) on how performance data should be presented, in order to develop effective feedback methods to facilitate the use of these data in decision making. DESIGN: A qualitative analysis of semi-structured face-to-face and telephone interviews. League tables and fictional box plots were presented as an illustrative guide. The themes covered in the interviews were the effectiveness of these two feedback formats, their positive and negative characteristics, and ideas for new and improved feedback mechanisms. PARTICIPANTS: Thirty-six stakeholders representing a range of clinical and non-clinical roles within palliative care and the wider health care system across a variety of statutory and non-statutory organizations from London and the West Midlands. RESULTS: Box plots were received more positively than league tables, and qualitative information was considered more appropriate than pictorial feedback. Conventional methods such as league tables and box plots were judged to lack essential information on which important decisions could be based, such as additional contextual information and the methodological assumptions of the instrument. Both feedback methods were considered useful as an impetus to further discussion. There was a consensus that feedback should be constructive and able to be adapted to the organizational realities in which UK health services function. CONCLUSION: Qualitative research was viewed as the right evidence for gaining an understanding of the quality of end of life care. Stakeholders highlighted the importance of the lay perspective, which requires approaches that illuminate the subjective meanings of patient experience. 相似文献
996.
目的提高对梅毒诊断的灵敏性和特异性。方法运用PER扩增了梅毒螺旋体(Tp)的DNA多聚酶I基因(polA)的特异性片段,检测了该方法的特异性和灵敏性;用该方法检测了118例生殖器溃疡,同时用Tp PCR试剂盒和血清学方法平行检测同批病人的溃疡或血清标本。结果polA PCR只在扩增Tp时有特异性产物,灵敏性约为20个Tp拷贝;检测118例生殖器溃疡标本,用Tp PCR试剂盒为对照,polA PCR方法的特异性和灵敏性分别为96.8%和95.7%,两种PCR检验结果差异无显著性(x2=0.25,P>0.05);polA PCR方法与血清学方法对一期梅毒诊断结果差异有显著性(x2=4.45,P<0.05)。结论polA PCR方法高度敏感、特异,在一期梅毒诊断中优于血清学方法,可作为血清学方法的补充用于梅毒的诊断。 相似文献
997.
998.
常规医疗设备招标存在问题的思考和对策--决策学多属性效用理论的实践探索 总被引:1,自引:0,他引:1
通过对常规医疗设备招标存在问题的思考,采用决策学多属性效用理论作为一种对策方法,并在实际操作中进行了尝试探索,以取得更好的效果. 相似文献
999.
目的通过观察OSAS患者经过有效治疗前后HRV的变化,评价患者的心率变异性变化情况。方法对51例OSAS病人在有效治疗前后同步进行PSG检查及动态心电监测,统计其HRV的时阈指标SDNN、rMSSD及频阈指标LF、HF及LF/HF,采用SPSS/PC统计软件中配对样本t检验进行处理。结果SDNN、LF、LF/HF等指标在治疗前后的差异有显著性(p<0·05),rMSSD、HF的变化无显著性差异(p>0·05)。结论有效治疗OSAS可使植物神经系统的功能得到恢复,降低心脏事件发生的危险性。 相似文献
1000.
Hiroki Sakamoto Masayuki Kitano Takeshi Nishio Yoshifumi Takeyama Chikao Yasuda Masatoshi Kudo 《Digestive endoscopy》2006,18(3):206-211
Endosonography‐guided celiac plexus neurolysis (EUS‐CPN) safely and effectively relieves pain associated with intra‐abdominal malignancies when the neurolytic is accurately injected. We applied contrast medium to evaluate the ethanol injection sites in patients who received EUS‐CPN due to abdominal pain caused by malignancies. We injected, under the guidance of endoscopic ultrasonography (EUS), ethanol containing 10% contrast medium into the celiac plexus of patients with intra‐abdominal pain due to malignancies. Immediately after the endoscopic therapy, patients underwent computed tomography (CT) to confirm the injection site. Images of distribution of injected solutions were classified into three groups. Injected solution dispersed in unilateral and bilateral anterocrural space was defined as ‘unilateral injection’ or ‘bilateral injection’, respectively. Injected solution located out of the anterocrural space was defined as ‘inappropriate injection’. Pre‐ and postprocedure pain was assessed using a standard analog scale. Before and 2, 4, 8, 12, and 16 weeks after the procedure, pain scores were evaluated. From April 2003 to May 2005, 13 patients were enrolled in this study. Improvement of pain score in the ‘bilateral injection’ and ‘unilateral injection’ groups was significantly superior to the change in the ‘inappropriate injection’ group. Although EUS‐CPN was effective in eight of 13 patients (61.5%), additional EUS‐CPN to the ‘inappropriate injection group’ increased the response rate to 84.6%. Injection of ethanol to the anterocrural space by EUS‐CPN produced adequate pain relief. Immediate examination by CT for confirmation of injection sites after EUS‐CPN would increase the likelihood of induction of pain relief. 相似文献