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71.
Summary The radioligand binding characteristics of [3H]haloperidol (in the presence of spiperone, 25 nmolL–1) were investigated in rat and human cerebellar membranes.In both rat and human cerebellar membrane preparations saturation studies with [3H]haloperidol (non-specific binding defined by pentazocine, 10 molL–1) demonstrated high affinity saturable specific binding to a homogenous population of binding sites (rat, Bmax 6693 ± 1242 fmol mg–1 protein, pKD 8.33 ± 0.08; human, Bmax 2550 ± 437 fmol mg–1 protein, pKD 8.59 ± 0.11; mean ± SEM, n = 3–6). Competition studies employing a wide range of structurally diverse competing compounds displayed that the [3H]haloperidol binding site was pharmacologically similar in both preparations and comparable to sigma recognition sites previously identified in various tissues originating from different species. In addition, with reference to the potential subtypes of sigma recognition sites, the labelling of these sites by low nanomolar concentrations of [3H]haloperidol provides evidence that they belong to the sigma-1 recognition site subtype.The present findings suggest that the pharmacology of the rat and human cerebellar sigma recognition site are directly comparable and provides further supporting evidence towards the use of [3H]haloperidol radioligand binding studies in the rat to detect sigma receptor ligands with potential therapeutic activity. Send offprint requests to: N.M. Barnes at the above address  相似文献   
72.
A European approach for resource management and strategic planning has been implemented in the HOSCOM project of AIM by defining information standards needed across countries, as well as a methodology to measure resources and costs at the institutional and interinstitutional level. A Euro Health Data Base (EHDB) has been obtained in order to test data availability and comparability as well as to validate models through macrocomparisons using case-mix (DRG's, refined grouping, disease staging) and microcomparisons based on three diseases (cardiac valve replacement, diabetes mellitus and hip fracture). The EHDB's presently based on 274 164 medical record summaries sampled from 7 countries allowed us to build prototypes (using Clipper, Prolog and SQL) in order to export uniform aggregates in the different countries, with standard software tools for statistical comparisons. It showed the present feasibility of using case-mix based on the European Minimum Basic Data Set (MBDS) and the difficulty of obtaining uniform data on resources and costs other than length of stay across countries. Medical data confidentiality was assured but not yet population-based representativity. Given the present state of the EHDB, problems have been clearly identified in order to be solved by international research and development projects in the near future.  相似文献   
73.
Patients have a right to consider that any information about themselves will be regarded as confidential, but inadvertently, and, very occasionally deliberately, that confidence may be broken. Therefore the principles on which the computer system at The London Hospital is based rest on maintaining confidentiality but at the same time using the facilities unique to the computer to the fullest extent for the benefit of patients. The system is described in outline, and a note is added of occasions when it would be desirable to suppress information on a patient and the reasons for so doing.  相似文献   
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75.
OBJECTIVE: To determine the validity of a clinical diagnosis of probable or possible dementia with Lewy bodies (DLB) made using International Consensus criteria. BACKGROUND: Validation studies based on retrospective chart reviews of autopsy-confirmed cases have suggested that diagnostic specificity for DLB is acceptable but case detection rates as low as 0.22 have been suggested. METHODS: We evaluated the first 50 cases reaching neuropathologic autopsy in a cohort to which Consensus clinical diagnostic criteria for DLB, National Institute for Neurological and Communicative Disorders and Stroke-Alzheimer's Disease and Related Disorders Association criteria for AD, and National Institute of Neurological Disorders and Stroke-Association Internationale pour la Recherche et l'Enseignement en Neurosciences criteria for vascular dementia (VaD) had been prospectively applied. RESULTS: Twenty-six clinical diagnoses of DLB, 19 of AD, and 5 of VaD were made. At autopsy, 29 DLB cases, 15 AD, 5 VaD, and 1 progressive supranuclear palsy were identified. The sensitivity and specificity of a clinical diagnosis of probable DLB in this sample were 0.83 and 0.95. Of the five cases receiving a false-negative diagnosis of DLB, significant fluctuation was present in four but visual hallucinations and spontaneous motor features of parkinsonism were generally absent. Thirty-one percent of the DLB cases had additional vascular pathology and in two cases this contributed to a misdiagnosis of VaD. No correlations were found between the distribution of Lewy bodies and clinical features. CONCLUSION: The Consensus criteria for DLB performed as well in this prospective study as those for AD and VaD, with a diagnostic sensitivity substantially higher than that reported by previous retrospective studies. DLB occurs in the absence of extrapyramidal features and in the presence of comorbid cerebrovascular disease. Fluctuation is an important diagnostic indicator, reliable measures of which need to be developed further.  相似文献   
76.
A dose-response curve for intravenous morphine and vomiting was investigated in children having day-stay tonsillectomy. A retrospective chart review was performed for the 164 children fulfilling the inclusion criteria. Morphine (mean 0.09 mg/kg SD 0.05) was used in 108 children in the perioperative period and a further 56 children were given no opioid. Fifty-five of these 164 children vomited and 20 children required an overnight stay in hospital because of vomiting. The probability of vomiting or overnight stay in hospital was related to morphine dose (by logistic regression). The overall probability of vomiting after morphine 0.1 mg/kg was 50% and the probability of admission for vomiting with this dose was 10%. Pharmacodynamic parameter estimates for postoperative vomiting were P0 (the baseline probability of vomiting, with no opioid) 0.115, Pmax (the maximal probability of vomiting due to morphine) 0.997, ED50 (morphine dose that induces an effect equivalent to 50% of the logit Pmax) 0.18 mg/kg. Parameter estimates for overnight stay because of vomiting after morphine administration were P0 0.038, Pmax 0.999, ED50 0.369 mg/kg. Satisfactory postoperative analgesia in children has been reported with morphine 0.05 to 0.15 mg/kg. Doses above 0.1 mg/kg are associated with a greater than 50% incidence of vomiting. Our data suggests that lower doses of morphine are associated with a decreased incidence of emesis after tonsillectomy in children.  相似文献   
77.
 目的 研究Ewing’s肉瘤细胞系 (RM 82 )X 射线外照射后肿瘤坏死因子 (TNF α)和转化生长因子 (TGF β)mRNA表达水平的变化 ,探讨X 射线诱导内源性TNF α和TGF β产生的可能性及意义。 方法 应用实时荧光RT PCR ,检测接受不同剂量X 线照射 (2Gy ,5Gy ,10Gy ,2 0Gy ,30Gy ,4 0Gy)和受照后不同时间 (1h ,3h ,6h ,12h ,2 4h ,4 8h ,72h)。TNF α和TGF βmRNA表达水平的变化。 结果 RM 82细胞TNF αmRNA表达水平较外照射前显著升高。一方面受照后TNF αmRNA表达逐渐升高 ,照射剂量达 4 0Gy时TNF αmRNA表达水平达高峰 ,为正常对照组的 10 8倍 ;另一方面 ,照射后 3h后TNF αmRNA表达逐渐升高 ,6h达高峰 ,为正常对照组的 18倍。相反 ,TGF βmRNA表达水平X 射线照射前后无显著变化。结论 Ewing’s肉瘤细胞系 (RM 82 )接受X 线照射后TNF αmRNA表达明显升高 ,且呈现时间、剂量依赖性。放射治疗可诱导Ewing’s肉瘤细胞系 (RM 82...  相似文献   
78.
PURPOSE: As the number of pediatric cancer survivors increases, so does the number of survivors previously exposed to anthracyclines as part of their cancer therapy. Because screening is costly, some have suggested that health-related quality of life (HRQL) measures might be useful in focusing screening tests on those patients with cases most likely to display positive findings. This study reports on the predictive ability of HRQL measures to detect patients with abnormalities on serial cardiac testing. METHODS: Using 127 patients from the ACE-Inhibitor after Anthracycline (AAA) Trial, this study compared serial measures of the Short Form-36 (SF-36; for ages > 13 years) and Child Health Questionnaire-Child Form 87 (CHQ-CF87; for ages < or = 13 years) to serial cardiac performance tests including echocardiographic shortening fraction, left ventricular end systolic wall stress (LVESWS), LVESWS-index, and maximal cardiac index (MCI; a measure of cardiac output at peak exercise). RESULTS: Generally, there was no clinically or statistically significant correlation between any HRQL measure and any cardiac function measure except between MCI and vitality and physical functioning. For each of these measures, the correlation between MCI was statistically significant (P < .006), but each HRQL subscale could explain no more than 7% of the variation in MCI. HRQL measures were not predictive of any other cardiac function measure. CONCLUSION: HRQL measures should not be used in isolation as a screen for cardiac function abnormalities in patients exposed to anthracylines who already have a mild degree of ventricular dysfunction. Patient history appears to be no substitute for cardiac testing in this cohort.  相似文献   
79.
AIM: The aim of this study was to simplify the technique of ROLL and sentinel node biopsy without compromising tumour excision and sentinel node biopsy. METHODS: Twenty patients with impalpable primary invasive breast carcinoma underwent an injection of 99mTc-nanocolloid mixed with radiographic contrast medium Iohexol into the centre of the lesion under ultrasound or stereotactic guidance pre-operatively. No guidewire localisation was performed. Under general anaesthesia, a periareolar intradermal/subcutaneous injection of patent blue-V dye was performed. The sentinel node was identified by blue-stained lymphatics and node and a hot spot on the gamma probe. Surgical excision of the primary tumour was then carried out using the gamma probe. RESULTS: In eight of 20 cases an immediate re-excision was carried out and on histological assessment, all 20 patients were clear of invasive disease at the margins. In two patients, in situ disease was present at the margins and a further re-excision was therefore performed. The sentinel node was identified in all cases. In all, five of 20 patients were node positive on routine HE staining. In a further two patients, tumour cells were identified by immunohistochemistry with CAM5.2 antibody. Completion axillary clearance in six patients confirmed that the sentinel node was the only positive node. CONCLUSIONS: This modification of the previously described ROLL technique is feasible and safe and does not compromise tumour excision or sentinel node detection.  相似文献   
80.
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