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1.
Gestational trophoblastic neoplasia (GTN) patients are treated according to the eight-variable International Federation of Gynaecology and Obstetrics (FIGO) scoring system, that aims to predict first-line single-agent chemotherapy resistance. FIGO is imperfect with one-third of low-risk patients developing disease resistance to first-line single-agent chemotherapy. We aimed to generate simplified models that improve upon FIGO. Logistic regression (LR) and multilayer perceptron (MLP) modelling (n = 4191) generated six models (M1-6). M1, all eight FIGO variables (scored data); M2, all eight FIGO variables (scored and raw data); M3, nonimaging variables (scored data); M4, nonimaging variables (scored and raw data); M5, imaging variables (scored data); and M6, pretreatment hCG (raw data) + imaging variables (scored data). Performance was compared to FIGO using true and false positive rates, positive and negative predictive values, diagnostic odds ratio, receiver operating characteristic (ROC) curves, Bland-Altman calibration plots, decision curve analysis and contingency tables. M1-6 were calibrated and outperformed FIGO on true positive rate and positive predictive value. Using LR and MLP, M1, M2 and M4 generated small improvements to the ROC curve and decision curve analysis. M3, M5 and M6 matched FIGO or performed less well. Compared to FIGO, most (excluding LR M4 and MLP M5) had significant discordance in patient classification (McNemar's test P < .05); 55-112 undertreated, 46-206 overtreated. Statistical modelling yielded only small gains over FIGO performance, arising through recategorisation of treatment-resistant patients, with a significant proportion of under/overtreatment as the available data have been used a priori to allocate primary chemotherapy. Streamlining FIGO should now be the focus.  相似文献   
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1. The frequent occurrence of hypothalamo-pituitary dysfunction in patients with eating disorders as well as prior reports that nutritional and endocrine status influence pituitary morphology, led us to hypothesize that pituitary size and shape may be altered in patients with eating disorders. 2. Magnetic resonance imaging (MRI) does not use ionizing radiation and is currently one of the most feasible modalities available to study the pituitary gland in vivo. Using MRI, we have previously reported in a preliminary study that female patients with eating disorders had significantly smaller pituitary glands than controls. In addition MRI excluded any pituitary mass lesions. 3. In this report, we confirm our previous MRI findings and provide further evidence of pituitary abnormalities in an expanded sample of eating disorder patients. Preliminary data on pituitary volume estimates from MRI scans are provided for a subset of patients and controls.  相似文献   
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Thirty-one patients presenting as orbital optic nerve glioma have been reviewed with maximum follow-up of 14 years. Sixteen of these patients have been reported on previously and further follow-up is provided. Sixteen patients had a stable clinical course with little change over a period of up to 13.5 years. Neurofibromatosis was relatively common in this group (11/16). Fifteen patients had progressive enlargement of the tumour; the incidence of neurofibromatosis in this group was low (4/15). Eleven of these patients were explored neurosurgically and the optic nerve totally excised in 10 of them. The proximal cut end was normal in six patients and the chiasm has apparently remained free of tumour in all of them. We suggest a method of management of primary optic nerve tumours, both meningiomas and gliomas, in young patients.  相似文献   
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We examined binding to excitatory amino acid and inhibitory amino acid receptors in frozen hippocampal sections prepared from surgical specimens resected from 8 individuals with medically refractory temporal lobe epilepsy. The excitatory receptors studied included N-methyl-D-aspartate (NMDA), strychnine-insensitive glycine, phencyclidine, and quisqualate. The inhibitory receptors studied were gamma-aminobutyric acid type A (GABAA) and benzodiazepine. Excitatory and inhibitory amino acid receptor binding were differentially altered in the patients with temporal lobe epilepsy in comparison to 8 age-comparable autopsy control subjects, and changes in receptor binding were regionally selective in four areas. Binding to phencyclidine receptors associated with the NMDA channel was reduced by 35 to 70% in all regions in the hippocampi of the patients. In contrast, binding to the NMDA recognition site and its associated glycine modulatory site was elevated by 20 to 110% in the cornu ammonis (CA) 1 area and dentate gyrus of the hippocampus of the patients. Binding to these sites was unaffected in area CA4. Binding to the quisqualate-type excitatory amino acid receptor was unchanged in all regions except the stratum lacunosum moleculare CA1, where it was increased by 63%. GABAA and benzodiazepine receptor binding was reduced by 20 to 60% in CA1 and CA4, but unchanged in dentate gyrus. The data indicate that excitatory and inhibitory amino acid receptors are altered in the hippocampus of patients with temporal lobe epilepsy.  相似文献   
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OBJECTIVE: To assess the impact and cost-effectiveness of two information-based provider reminder interventions designed to improve self-care management and outcomes of heart failure (HF) patients. DATA SOURCES/STUDY SETTING: Interview and agency administrative data on 628 home care patients with a primary diagnosis of HF. STUDY DESIGN: Patients were treated by nurses randomly assigned to usual care or one of two intervention groups. The basic intervention was an e-mail to the patient's nurse highlighting six HF-specific clinical recommendations. The augmented intervention supplemented the initial nurse reminder with additional clinician and patient resources. DATA COLLECTION: Patient interviews were conducted 45 days post admission to measure self-management behaviors, HF-specific outcomes (Kansas City Cardiomyopathy Questionnaire-KCCQ), health-related quality of life (EuroQoL), and service use. PRINCIPAL FINDINGS: Both interventions improved the mean KCCQ summary score (15.3 and 12.9 percent, respectively) relative to usual care (p< or =.05). The basic intervention also yielded a higher EuroQoL score relative to usual care (p< or =.05). In addition, the interventions had a positive impact on medication knowledge, diet, and weight monitoring. The basic intervention was more cost-effective than the augmented intervention in improving clinical outcomes. CONCLUSIONS: This study demonstrates the positive impact of targeting evidence-based computer reminders to home health nurses to improve patient self-care behaviors, knowledge, and clinical outcomes. It also advances the field's limited understanding of the cost-effectiveness of selected strategies for translating research into practice.  相似文献   
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Recent New Labour policy for the ‘modernisation’ of Government places a good deal of emphasis on decentralisation. This emphasis is particularly marked in relation to the organisation of primary care. However, like hospitals and other National Health Service institutions, primary care trusts (PCTs) are subject to a substantial raft of centrally established performance targets and indicators, including those which contribute to the public award of between zero and three performance ‘stars’. This raises questions about the extent to which employees can exercise autonomy in the context of rigid top‐down directives. This paper presents findings from a study using participant observation and interviews to examine the impact of a training course aimed ostensibly at increasing employee autonomy in an English PCT. The suggestion is that attempts to make employees more autonomous can be seen as a strategy for increasing central control based upon the internalisation by the employees of centrally promulgated values. The attraction of such strategies is that they may be potentially more effective and less costly than alternative strategies of direct control. However, the study suggests that the outcome of attempts by such methods as programmes to increase employee autonomy may be very different from those intended.  相似文献   
9.
Technetium-99m RBC scintigraphy in the evaluation of small bowel leiomyoma   总被引:1,自引:0,他引:1  
Hypervascularity and persistent uptake were demonstrated in a small bowel leiomyoma not actively bleeding at the time of Tc-99m RBC scintigraphy. The potential value of Tc-99m RBC scanning in the evaluation of benign small bowel tumors is discussed.  相似文献   
10.
BACKGROUND: Vitiligo is the most common pigmentary disorder with a global incidence from 0.1% to 2% in different geographical areas. Histopathology and histochemistry have shown the reduction of melanocytes in achromic patches, but microscopic changes of lesional and non-lesional skin are still not completely understood. Reflectance confocal microscopy (RCM), based on the different light reflectance index of cutaneous structures, allowed in vivo, en face microscopic evaluation of superficial skin layers with a resolution similar to skin histology. AIM: The purpose of this study was to evaluate RCM features of lesional and non-lesional skin of vitiligo patients. Moreover, re-pigmented areas were taken into consideration in order to evaluate melanocyte response to ultraviolet B (UVB) radiation. SUBJECTS AND METHODS: Sixteen patients of different phototypes affected by active non-segmental vitiligo and 10 controls were enrolled in the study. In vivo skin imaging was done using a commercially available RCM (Lucid, Vivascope 1500. Re-pigmented areas from 6 to 16 patients (after UVB narrow-band therapy) were also examined. RESULTS: Vitiligo lesions showed the disappearance of the bright rings normally seen at the dermo-epidermal junction. Moreover, non-lesional skin of vitiligo patients showed unexpected changes as the presence of half-rings or scalloped border-like features of the bright papillary rings. In re-pigmented areas after UVB narrow band therapy, the presence of activated, dendritic melanocytes was seen. CONCLUSIONS: Considering our results, and following further studies, RCM clinical applications could be used in the therapeutic monitoring and evaluation of the evolution of vitiligo.  相似文献   
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