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21.
目的 介绍一种简单实用的磁共振颅脑图像分割算法K 最近邻 (简称K NN)规则 ,并利用该算法对磁共振颅脑图像进行分割研究。方法 该方法是一个多步处理过程。首先利用边界跟踪法对磁共振颅脑图像进行预处理 ,剔除颅骨和肌肉等非脑组织 ,只保留大脑结构 ;然后利用K NN规则对大脑结构进行分割 ,从大脑结构中分别提取出白质 (WM)、灰质 (GM)和脑脊液 (CSF)。结果 分割算法在预处理步中能精确地分割出大脑结构 ,在K NN分割步中能很好地从大脑结构中分割出WM、GM和CSF。结论 该算法在磁共振颅脑图像的分割中简单实用 ,具有很强的鲁棒性和稳定性。 相似文献
22.
Interactive risk factors for treatment adherence in a chronic psychotic disorders population 总被引:4,自引:0,他引:4
This study identified the unique and primary contributions of several concurrent risk factors for poor adherence to treatment recommendations in a clinic population of individuals with chronic psychotic disorders, i.e. 48% had DSM-IV diagnoses of schizoaffective disorder, 38% had schizophrenia, paranoid type, 12% had schizophrenia, undifferentiated type, and 2% had affective disorder with psychotic features. The target cohort consisted of 87 consecutive admissions to a continuing day treatment program. As part of a services-oriented quality assurance program, clinical staff completed rating scales for all patients. These included the BASIS-32 rating scale, which consisted of the following five subscales: psychosis; depression/anxiety; impulsive/addictive behavior; relation to self and others; and daily living and role functioning, and the Working Alliance Inventory-short form (therapist version), which consisted of the following three subscales: goal; task; and bond. These data were used to identify risk factors that weaken a patient's adherence to medication and non-medication treatment during the first 2 weeks of treatment in the clinic. Medication treatment consisted of both typical and atypical neuroleptic medications, with most patients being on multiple medications. Correlational analyses suggested that many of the risk factor variables were significantly associated with poor treatment adherence. Regression analyses suggested that the degree of psychoticism was most strongly associated with poor adherence to medication treatment and that difficulties relating to self and others were the strongest predictor of poor adherence to non-medication treatment. A large-sample services research design such as this can begin to determine patterns of associations between previous identified risk factors and poor treatment adherence in individuals with chronic psychotic disorders. 相似文献
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24.
Medication error forms a major proportion of the errors in the medical system. Despite many studies of adverse drug events, there are no systematic ways of ensuring safety, or of assessing how safe a pharmaceutical system is. Risk assessment is required in hazardous industries such as nuclear power or oil and gas. Risk assessments involve identifying the defences and assessing their effectiveness and are relatively uncommon in clinical pharmacy , as opposed to reactive approaches involving incident analyses. Risk factors, that degrade barriers, can be identified and their effect measured. A risk assessment structure for pharmacy processes is proposed that can also be used to support incident investigation and analysis processes and provide a standard for audit. 相似文献
25.
Lee SH Huang JW Hung KY Leu LJ Kan YT Yang CS Chung Wu D Huang CL Chen PY Chen JS Chen WY 《Artificial organs》2000,24(11):841-844
A multicenter collaborative study was performed to investigate the prevalence of abnormal blood contents of 6 trace metals, copper (Cu), zinc (Zn), aluminum (Al), lead (Pb), cadmium (Cd), and mercury (Hg), in hemodialysis (HD) patients and to analyze their relationship with the medications, such as CaCO3, Ca acetate, Al containing phosphate-binding agents, 1,25-dihydroxy vitD3, 1-hydroxy vitD3, and erythropoietin (EPO), as well as hematocrit level, by chi-square statistics. From 6 medical centers in Taiwan, we included 456 patients in maintenance HD for more than 4 months for this study, and they had continued the previously mentioned medications for at least 3 months. Blood samples were collected before initiating HD, and atomic absorption spectrophotometry was used to measure plasma levels of Cu, Zn, and Al as well as whole blood levels of Pb, Cd, and Hg. Three hundred seventy-five (78%) of the HD patients had low plasma Zn levels, that is, <800 microg/L, and the mean (+/-SD) concentration was 705.8 (+/-128.23) microg/L in all subjects. One hundred forty-one (31%) of the HD patients had high plasma Al, that is, >50 microg/L, and the mean (+/-SD) was 44.30 (+/-28.28) microg/L in all subjects. Three hundred thirty-three (73%) of the dialysis patients had high Cd levels, that is, >2.5 microg/L, and the mean (+/-SD) was 3.32 (+/-1.49) microg/L in all subjects. The majority of HD patients had normal blood levels of Cu, PB, and Hg. Only 21 (4. 6%), 5 (1.1%), and 3 (0.06%) patients had elevated blood levels of Cu, Pb, and Hg, respectively. Their mean (+/-SD) blood concentration of Cu, Pb, and Hg were 1,049.78 (+/-233.25) microg/L, 7.45 (+/-3.95) microg/dL, and 3.17 (+/-25.56) microg/L, respectively. Three patients had elevated plasma Hg concentrations, that is, 546, 12.6, and 24.0 microg/L, respectively. In the 152 normal healthy age and sex matched control group, the blood levels of Al, Cd, and Pb were all significantly lower than the HD patients. However, the levels of Cu and Zn were higher in the control group. The Hg level was not significantly different in both groups. There was no statistical difference between patients with normal and abnormal blood levels of trace metals in various medications except Al containing phosphate binder. The Al containing phosphate binder users had significantly higher plasma Al levels (54.71 +/- 26.70 versus 41.15 +/- 28.03 microg/L, p < 0.001) and hematocrit levels (29.61 +/- 4.61 versus 27. 81 +/- 3.91, p < 0.0005). There was no statistical correlation between erythropoietin (EPO) dose and hematocrit level in these patients. In conclusion, the blood level of trace metals of these HD patients except Al was not related to their medications. However, caution must be exercised in interpreting this result as dose and duration of medication; efficiency of HD and water treatment may play an important role. Otherwise, environmental factors, diet, and the aging process may contribute to the trace metal burden in uremia. Thus, Zn and Cu are abundant in seafood, and Cd is abundant in contaminated plants such as rice. 相似文献
26.
邵雷 《针灸推拿医学(英文版)》2004,2(6):18-20
将36例糖尿病Ⅱ型患者分为西药组和针刺组,分别予降糖药物和针刺治疗.治疗前患者血糖、HbA1,各项心脏植物神经功能试验均异常.治疗1个月西药组血糖及HbA1显著下降,而其余各项指标均无显著变化.针刺组血糖HbA1无显著变化,但乏氏指数、立卧位心率差、30/15R-R期间比值、异常项目数均显著改善.说明针刺可以改善心脏植物神经功能. 相似文献
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28.
Prosopo-thoracopagus twins are united from the face down to the umbilicus, none with union in the brain but all with visceral
anomalies intermediate between those of cephalopagus and thoracopagus. In a review of over 1200 cases of conjoined twins reported
during the past 100 years, there were 14 that illustrate the continuum between cephalopagus and thoracopagus, including three
that were united only from the cervical region to the umbilicus. Classic cephalopagus twins are joined from the top of the
head to the umbilicus, sharing a single foregut as well as two relatively normal hearts, the “posterior” one often diminished.
Typical thoracopagus, however, are conjoined only from the upper thorax to the umbilicus, each twin with a normal foregut
but both sharing a single complex multiventricular heart. The intermediate cases shared either a single very abnormal heart
or two hearts united by double aortic arches, and all except one had a single foregut. It is these cases intermediate between
cephalopagus and thoracopagus which are the subject of this report.
Received September 11, 1996; accepted December 16, 1996 相似文献
29.
针刺治疗稳定性心绞痛30例体会 总被引:2,自引:0,他引:2
目的:比较针刺与药物治疗稳定性心绞痛的疗效差异。方法:随机选取稳定性心绞痛患者,分为针刺组30例、药物组2 2例,分别比较治疗后两组症状、心电图及硝酸甘油停减情况。结果:症状疗效方面:针刺组有效率为90 .0 0 %,药物组有效率为81 .82 %,两组比较有显著性差异(P <0 .0 5 )。心电图改善情况两组未见明显差异。硝酸甘油停减情况:针刺组停药率为2 3.3%,药物组停药率为1 8.2 %,两组比较无明显差异。结论:针刺具有明显改善稳定性心绞痛症状的功效。 相似文献
30.
目的:研究抗茵药使用中药物治疗错误(ME)的发生情况,探讨其防范重点。方法:药师深入中心ICU病房,通过调查病历、直接观察的方式发现抗茵药ME。结果:10个月研究期间共发现ME301次,其中可预防药物不良事件(ADE)19次(3.3%),潜在ADE94次(16.2%)。有潜在危害ME(可预防的ADE+潜在ADE)中有生命威胁6次(5.3%),严重88次(77.9%),明显19次(16.8%)。结论:抗茵药使用中ME经常发生,其中约1/3有潜在危害且往往带来严重后果,应该采取措施防范ME、特别是有潜在危害ME的发生。 相似文献