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21.
Data from analgesic clinical trials have characteristics such as ordered categorical longitudinal responses with repeated measures, delay of effect with respect to analgesic plasma concentration, and right-hand censoring of response due to remedication. In order to determine the concentration-effect relationship of such data, we propose convolving an empirical function for plasma concentration, in the form of broken lines which connect each pair of neighboring observations, with a monoexponential function, to generate effect site concentration Effect site concentration and time are used, simultaneously, as independent variables in the fit of the model for the logit of the probability of having a specific pain relief (PR) score at each time point pre-remedication, via maximum likelihood. Using corresponding effect site concentration, the probabilities of having specific PR scores post-remedication are predicted via the concentration-response relationship established. The overall (pre- and post-remedication) predictions and corresponding standard errors for the responses are then estimated. Inference of the PR scoring, using a posterior method, is proposed. An illustration using real data is used to demonstrate these methods.  相似文献   
22.
Design and use of internal receiver coils for magnetic resonance imaging   总被引:2,自引:0,他引:2  
This review describes coils for MRI that are inserted into the body through natural orifices. It covers the design and implementation of small internal receiver coils for use in the pelvis and gastrointestinal tract. Normal anatomy delineated by the high resolution obtained by using these coils and the appearances in a number of disease states for each clinical application are described.  相似文献   
23.
Even at an early stage, hepatocellular carcinoma (HCC) in patients with cirrhosis is often deemed unresectable because of limited liver reserve. In these circumstances, liver transplantation (LTx) offers some hope for palliation or cure. The results of LTx for selected cirrhotic patients with HCC were analysed. The outcomes were compared with those of patients who underwent LTx for other forms of hepatic malignancy and those who underwent LTx for non-malignant conditions. Four hundred and eighty LTx were performed in 441 patients between January 1986 and December 1998. Twenty-eight LTx recipients (25 males, 3 females) of mean age 51 (14 63) yr had cirrhosis and HCC. Twenty-seven patients had underlying predisposing conditions (11 had hepatitis B, 10 had hepatitis C, 2 had hepatitis B and C, 1 had haemochromatosis, 1 had autoimmune hepatitis, 1 had alcoholic cirrhosis and 1 had alpha-1 antitrypsin deficiency). In 22 patients, HCC was diagnosed pre-LTx, and in 6 patients, the cancers were discovered incidentally. The average tumour size and number were 2.8 (0.4-11.5) cm and 1.3 (1-4), respectively. Two patients with known HCC died during and shortly after the LTx operation. Of the other patients, 3 died; 1 died of HCC recurrence 18 months post-LTx, 1 died of graft failure from recurrent hepatitis C and 1 died of fungal sepsis. Twenty-three (82%) patients survived to 22.5 (0.5-96) months post-LTx without HCC recurrence and with 1- and 3-yr actuarial patient survival rates of 87 and 76%, respectively. Equivalent survival rates of patients who underwent LTx for other malignancies (n = 11) were 82 and 46% (p = NS), and for those who underwent LTx for benign causes (n = 402), they were 77 and 73% (p = NS). All 15 patients with known HCC, who met the selection criteria now in use, survived. LTx can result in prolonged. cancer-free survival in a good proportion of patients with cirrhosis and HCC, particularly when the cancers are incidental, or when diagnosed pre-LTx, conforming to established selection criteria. An active LTx programme for this group of patients is justified.  相似文献   
24.
晚期肺癌73例外科治疗分析   总被引:1,自引:0,他引:1  
目的 总结近9a实施的肺癌手术203例,其中属于Ⅲb或Ⅳ期的晚期肺癌73例,旨在讨论晚期肺癌的手术指征,手术操作要点。方法 行全肺切除18例(左肺15例,右肺3例),肺叶切除54例,肺癌切除后复发余肺切除1例,经心包内处理肺血管17例,合并民房部分切除2例;支气管成形术13敢管隆凸成形术1例。结果 除1例因急性呼吸功能衰竭导致死亡外,其余均临床治愈,术后生存率1a内为95%,1a以不足2a为80%  相似文献   
25.
Neuropathologic substrates of ischemic vascular dementia   总被引:19,自引:0,他引:19  
Ischemic vascular dementia (IVD) is a relatively uncommon entity, in the course of which multiple ischemic brain lesions result in progressive cognitive and memory impairment. Ischemic brain lesions may also aggravate the neuropsychologic deficit of Alzheimer disease (AD). In this review we summarize our experience based upon autopsy examination of the central nervous system in 20 patients (age range 68-92 years) enrolled in a longitudinal investigation of structural, neurochemical, functional neuroimaging, and neuropsychologic components of IVD, especially dementia associated with cerebral microvascular disease. While cystic infarcts were present in the CNS of 5 patients, the most commonly observed neuropathologic abnormalities were lacunar infarcts and microinfarcts--both types of lesion were encountered in over half of patients' brains. Evidence of (remote) hippocampal injury was found in 11/20 patients. Severe atherosclerosis and arterio/ arteriolosclerosis were both associated with the occurrence of multiple lacunar infarcts. Pronounced cerebral amyloid angiopathy (CAA) was noted in a single patient, who also showed other microscopic changes of severe AD. While fairly unusual as a nosologic entity, IVD appears to correlate with widespread small ischemic lesions distributed throughout the CNS. We furthermore propose an approach to quantifying the burden of ischemic vascular and parenchymal disease that may be associated with a dementia syndrome. A brief review of neuropathologic features of vascular dementia (both familial and sporadic) is presented.  相似文献   
26.
Primary graft dysfunction after liver transplantation   总被引:5,自引:0,他引:5  
  相似文献   
27.
28.
CT导引注射胶原酶治疗腰椎间盘突出症的临床研究   总被引:10,自引:2,他引:8       下载免费PDF全文
目的:探讨CT引导下椎间盘突出的髓核内和突出物表面注射胶原酶治疗椎间盘突出 的效果。方法:对90例椎间盘突出的患者在CT导引下分别于椎间盘突出的髓核内和突出物的表达注射胶原酶,所有患者随访3个月 ̄2年,其中30例行CT复查。结果:穿刺成功率100%,术后随访3个月 ̄2年,优良率为95.6%,29例CT随访突出物 部分缩小或消失(96.7%),本组无并发症。结论”腰椎间盘突出的髓核内和突出物的表面共  相似文献   
29.
Cheam EW  Chui PT 《Anaesthesia》2000,55(4):323-326
In a double-blind randomised study, we compared conditions during insertion of the laryngeal mask airway in 150 patients who received either fentanyl 1 microg.kg-1, mivacurium 0.04 mg.kg-1 or normal saline, before induction of anaesthesia with propofol 2 mg.kg-1. Insertion conditions, including mouth opening, swallowing, gagging or coughing, head or limb movement and ease of insertion, were each graded using a three-point scale. The median (interquartile range) summed insertion scores were more favourable with the use of fentanyl [8.0 (7.0-9.0)] and mivacurium [7.5 (6.8-8.3)] than with normal saline [9.0 (7.8-10.3); p < 0.01]. Fentanyl and mivacurium decreased swallowing and head or limb movement, and mivacurium improved mouth opening. Insertion conditions were similar between fentanyl and mivacurium, while both prolonged apnoea. Fentanyl and mivacurium are equally effective in facilitating insertion of the laryngeal mask airway following anaesthetic induction with propofol.  相似文献   
30.
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