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Immediate reconstruction of more than 1000 breasts was performed on high-risk patients on whom a prophylactic mastectomy was done. The mastectomy removes as much breast tissue as possible while leaving sufficient skin, and possibly the nipple-areola complex, to enable immediate reconstruction. The creation of symmetrical, well-balanced muscle pockets for the implant is the most important factor in producing satisfactory results in these cases.  相似文献   
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An i.v. challenge dose of clomipramine (12.5 mg) was given to eight outpatients with major depression. The procedure facilitated the examination of all-night sleep and sleep-related neuroendocrine changes (cortisol, growth hormone, and prolactin). In comparison to baseline saline nights, the patients experienced a profound suppression of rapid eye movement (REM) sleep throughout the night with no rebound recovery in the second half of the night. Furthermore, REM-suppressing effects were noted on the following no-drug night. In contrast, little effect on delta wave sleep was found, except for increased consolidation of delta waves within stage 3 and 4 sleep. Delta sleep measures were significantly correlated with levels of cortisol and growth hormone.  相似文献   
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Ruggieri  PM; Laub  GA; Masaryk  TJ; Modic  MT 《Radiology》1989,171(3):785-791
The technique and feasibility of magnetic resonance (MR) angiography of intracranial vessels were studied in 35 healthy volunteers. Variations in image orientation, repetition time (TR), and flip angle were evaluated to determine their effects on flow-related enhancement. Gradient modifications--including echo time (TE), motion compensation, bandwidth, and field of view--were also studied in an effort to reduce motion-induced phase shifts. Results indicated that a FISP (fast imaging with steady precession) sequence with a TR of 50 msec, TE of 15 msec, velocity compensation in the read and section-select directions, acceleration compensation in the read direction, anisotropic volume, and a 1.25-mm partition thickness produced three-dimensional angiographic MR images that were accurate and reproducible in the depiction of the major intracranial vessels. Difficulties with field of view, persistent signal void secondary to higher-order motion, and spatial resolution remain major problems requiring additional study.  相似文献   
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Transcranial Magnetic Stimulation (TMS) induces electrical currents in the brain to stimulate neural tissue. This article reviews our present understanding of TMS methodology, focusing on its biophysical foundations. We concentrate on how the laws of electromagnetic induction apply to TMS; addressing issues such as the location, area (i.e., focality), depth, and mechanism of TMS. We also present a review of the present limitations and future potential of the technique.  相似文献   
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The danger management strategies of low‐income African American women who live in a public housing community characterized by chronic violence are examined. Based on qualitative interviews with 18 single mothers, we explored the violent community dangers with which women contend, the nature of this violence, the strategies used to deal with community violence, and their benefits and costs to family and community life. Findings show that multiple types of violence characterized life in the community and that this violence has specific physical locations, a particular set of actors, and a temporal rhythm. Women's responses to violence were nonconfrontational and family focused in nature. These efforts were effective in keeping women and their children safe, but did not reduce the prevalence of violence.  相似文献   
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Paediatric dacryocystorhinostomy   总被引:1,自引:0,他引:1  
Of 258 cases of dacryocystorhinostomy performed on children in the period September 1981 to September 1991, 130 were for simple, unresolved congenital nasolacrimal duct obstruction. Other indications for surgery included punctal agenesis, lacrimal fistula, post-traumatic and post-inflammatory canalicular obstruction. Of 177 children without canalicular pathology, 171 (96%) were relieved of symptoms with one operation, without canalicular intubation. Of 81 cases with canalicular disease, 55 of 70 (79%) who underwent DCR plus canalicular intubation, and 10 of 11 who underwent DCR plus Lester-Jones tube, were substantially improved with one operation. No child required peroperative or postoperative blood transfusion. Dacryocystorhinostomy in childhood, in experienced surgical hands, is a safe procedure, achieving relief of symptoms in most cases, particularly in the absence of canalicular disease.  相似文献   
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