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21.
AIM: The aim of this retrospective study was to measure the accuracy of stereotactic guided 14 gauge core biopsy in distinguishing between benign and malignant causes of a mammographically detected stellate breast lesion and to assess the impact of the number of core samples taken on the sensitivity for detection of malignancy. MATERIALS AND METHODS: Seventy-two patients with mammographically detected stellate lesions of the breast formed the study group. All patients in the study group underwent multiple 14 gauge core biopsies using prone stereotactic breast biopsy equipment. The diagnostic accuracy of the technique was measured by retrospectively comparing the outcome with the core biopsy results. The result of each core sample was separately recorded to allow analysis of the effect of increasing the number of samples on accuracy. RESULTS: Nine of 72 (12%) did not have surgery. Forty of 72 (56%) had a benign surgical outcome and 23/72 (32%) a malignant surgical outcome [7/72 (10%) non-invasive, 16/72 (22%) invasive carcinoma]. The absolute sensitivity for multiple stereotactic guided core biopsies of stellate lesions for the detection of malignancy was 78% with a complete sensitivity of 100%. The sensitivity for the detection of invasive carcinoma was 94% (15 out of 16 patients). No statistically significant improvement in sensitivity was shown for multiple samples vs one sample, but in two patients, malignant tissue was only found in core samples 6-9, the first five cores showing atypia only. CONCLUSION: Multiple stereotactic guided 14 gauge core biopsies accurately distinguish malignant from benign causes of stellate breast lesions. When core biopsy histology is malignant, therapeutic surgery can be planned. When the core biopsy shows typical features of a benign radial scar, diagnostic surgical excision may not be required to confirm the diagnosis.Kirwan, S. E., (2000). Clinical Radiology55, 763-766.  相似文献   
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Dopamine-replacement strategies form the basis of most symptomatic treatments for Parkinson's disease. However, since long-term dopamine-replacement therapies are characterized by many side effects, most notably dyskinesia, the concept of a nondopaminergic therapy for Parkinson's disease has attracted great interest. To date, it has proved difficult to devise a nondopaminergic therapy with efficacy comparable to that of dopamine replacement. In animal models of Parkinson's disease, loss of striatal dopamine leads to enhanced excitation of striatal NR2B-containing NMDA receptors. This is responsible, in part at least, for generating parkinsonian symptoms. Here we demonstrate that, in the MPTP-lesioned marmoset, monotherapy with the NR2B-selective NMDA receptor antagonist, ifenprodil, administered de novo, has antiparkinsonian effects equivalent to those of l-DOPA (administered as its methyl ester form). In MPTP-lesioned marmosets, median mobility scores, following vehicle-treatment were 12.5/h (range 6-21), compared to 61/h (range 26-121) in normal, non-MPTP-lesioned animals. Following ifenprodil (10 mg/kg) treatment in MPTP-lesioned marmosets, the median mobility score was 66/h (range 34-93), and following l-DOPA (10 mg/kg i.p.) treatment 89/h (range 82-92). The data support the proposal that NR2B-selective NMDA receptor antagonists have potential as a nondopaminergic monotherapy for the treatment of parkinsonian symptoms when given de novo.  相似文献   
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Nash MS  Wood JP  Melena J  Osborne NN 《Brain research》2000,856(1-2):236-239
The effect of flupirtine on the loss of retinal ganglion cells following transient elevation of intraocular pressure (experimental ischaemia) or NMDA-induced excitotoxicity was studied. Ischaemia (60 min) or intravitreal injection of NMDA (20 nmol) caused a decrease in Thy-1 mRNA and Thy-1 immunoreactivity which are associated with ganglion cells. Administration of flupirtine counteracted these changes. Moreover, flupirtine dose-dependently inhibited NMDA-induced 45Ca(2+) influx into cultured cortical neurones and retinal pieces in vitro with maximal inhibition being observed at 200 microM. A similar concentration of flupirtine failed to inhibit kainate-stimulated calcium influx into cultured cortical neurones. In addition, flupirtine had no significant effect on [3H]nitrendipine or [3H]diltiazem binding to cortical membranes. The present studies are consistent with previous findings which suggested flupirtine to act as a NMDA antagonist by a mechanism that still remains to be clarified.  相似文献   
24.
We report our experience of using latissimus dorsi myocutaneous flaps after failed conservation for breast carcinoma. Twenty-nine patients were treated by two methods of reconstruction. Seventeen patients with central recurrent tumours and three patients with radiation necrosis of the breast were treated by total mastectomy and latissimus dorsi reconstitution with silicone implant. Nine patients underwent latissimus dorsi reconstruction with preservation of the nipple for recurrent peripheral tumours. After a mean follow up period of 20.2 months no local recurrences have been observed but a longer period of follow-up is necessary to evaluate the likely long term recurrence rate.  相似文献   
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The present study was undertaken to replicate an earlier experiment and to clarify which factors in this previous experiment (Nash, Johnson, & Tipton, 1979) were responsible for the obtained child-like behaviors of hypnotically regressed Ss. As in the previous study, 3 characteristics of the transitional object relationship (spontaneity, specificity, and intensity) were used as the primary criteria to investigate the effects of hypnotic age regression when Ss were regressed to age 3 and placed in 3 home situations. While in the previous study E suggested separation anxiety and isolation during the 3 home situations (mother-absent condition), the present study deleted all references to anxiety and isolation, and replaced them with suggestions of security and maternal proximity (mother-present condition). As expected, the mother-present versus mother-absent conditions led to similar hypnotized-simulating differences. In further accord with predictions, hypnotized Ss and simulating Ss requested a transitional object infrequently in the presence of mother. The importance of using dependent measures which index affective processes germane to interpersonal affect-laden experience is discussed.  相似文献   
28.
A summary of 3 papers of special interest to researchers and clinicians that appeared in the general scientific and medical literatures. All are robust, empirically grounded studies, however, each differs in its approach and design. These studies are exemplars of customizing design to the question asked and the opportunities afforded by setting. The first addresses delusions of alien control in the human brain; the second examines mechanisms accounting for the efficacy of hypnosis in the treatment of irritable bowel syndrome; the third is an extraordinarily clever empirically grounded N-of-1 case study tracking the behavioral treatment of a teenager with motor and vocal tics. Taken together, these three studies illustrate the variety of research designs that can be used to bring evidence to bear on important matters of theory and practice.  相似文献   
29.
Although clinicians typically possess considerable interest in research, especially about which interventions do and do not work, all too often they dismiss the notion that they themselves can make viable scientific contributions to the outcome literature. This derives from an unfortunate assumption that the only true experiment is a between-groups experiment. There is another form of true experiment that is perfectly compatible with real-world clinical practice: the single-case time-series design. Intensive and systematic tracking of one or a few patients over time can yield viable inferences about efficacy, effectiveness, and, under some circumstances, mechanism of change. This paper describes how clinicians working with hypnosis can carry out such research. The rationale and essential features of time-series studies are outlined; each design is illustrated with actual studies from the hypnosis literature; and new methods of statistical analysis, well within the statistical competence of practitioners, are described.  相似文献   
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