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81.
The objective of this study was to determine the frequency and significance of the MR findings of incomplete shell collapse for detecting implant rupture in a series of surgically removed breast prostheses. MR images of 86 breast implants in 44 patients were studied retrospectively and correlated with surgical findings at explanation. MR findings included (a) complete shell collapse (linguine sign), 21 implants; (b) incomplete shell collapse (subcapsular line sign, teardrop sign, and keyhole sign), 33 implants; (c) radial folds, 31 implants; and (d) normal, 1 implant. The subcapsular line sign was seen in 26 implants, the teardrop sign was seen in 27 implants, and the keyhole sign was seen in 23 implants. At surgery, 48 implants were found to be ruptured and 38 were intact. The MR findings of ruptured implants showed signs of incomplete collapse in 52% (n = 25), linguine sign in 44% (n = 21), and radial folds in 4% (n = 2). The linguine sign perfectly predicted implant rupture, but sensitivity was low. Findings of incomplete shell collapse improved sensitivity and negative predictive values, and the subcapsular line sign produced a significant incremental increase in predictive ability. MRI signs of incomplete shell collapse were more common than the linguine sign in ruptured implants and are significant contributors to the high sensitivity and negative predictive values of MRI for evaluating implant integrity.  相似文献   
82.
ABSTRACT: For students progressing from sixth to eighth grade, an enhanced Alcohol Misuse Prevention Study (AMPS) curriculum that emphasized social pressure resistance training, peer support, and norm-setting was developed, implemented, and evaluated. Schools were randomly assigned within communities to curriculum or control groups. Students were pretested early in sixth grade before the intervention and posttested at the end of sixth, seventh, and eighth grades. Results indicated the curriculum was effective in increasing students' knowledge of curriculum material, and among the subgroup of students who had used alcohol unsupervised by adults before the pretest, in reducing the rate of increase of alcohol misuse. The findings result from a replication of the analytic approach used with the initial AMPS cohort data.  相似文献   
83.
The expression of sodium channel α-subunit isoforms in astrocytes in adult rat spinal cord and optic nerve was examined utilizing immunocytochemical methods with antibodies generated against conserved and subtype-specific sequences of the sodium channel. In adult rat spinal cord, astrocytes within the dorsal and ventral funiculi were immunolabelled with antibody SP20, which recognizes a conserved sequence within sodium channel types I, II, and III. In addition, astrocytes within these spinal cord white matter tracts were immunostained with antibody SP11-II, which recognizes sodium channel type II. Antibodies SP11-I and SP32-III, which are directed against subtype-specific sequences in sodium channel types I and III, respectively, did not label astrocytes in the dorsal and ventral funiculi of the spinal cord. In optic nerves, astrocytes were immunostained with antibody SP20. However, no detectable labelling of cells within the optic nerve was observed with antibodies SP11-I, SP11-II, and SP32-III. These observations demonstrate that sodium channel II is expressed by astrocytes in spinal cord white matter. Moreover, these data suggest that regional factors regulate the level of sodium channel isoform expression in astrocytes.  相似文献   
84.
Surgical treatment of colostomy complications   总被引:16,自引:0,他引:16  
One hundred and twenty-three patients (M:F, 0.9:1; mean age 62 years) underwent 156 operations between 1954 and 1984 for correction of late colostomy complications (stenosis 65 patients, prolapse 16 patients, paracolostomy hernia 42 patients). Sixty-three per cent of patients eventually had a good result but in some up to 5 operations were necessary. Local excision of scar tissue at the mucocutaneous junction was associated with a 61 per cent (43/71) success rate for relief of colostomy stenosis. Where local fixation failed to prevent recurrent colostomy prolapse (13/20, 65 per cent of local fixation operations), colectomy and ileostomy was the most effective second procedure (2/3, 67 per cent success rate). Where local repair of a paracolostomy hernia failed (15/32, 47 per cent of local operations), resiting of the stoma to the umbilicus or right side of the abdomen produced better results (3/7, 43 per cent success rate) than resiting to another trephine on the left side of the abdomen (2/14, 14 per cent success rate).  相似文献   
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This article distills key issues and controversies in the field of international disaster mental health. It offers perspectives from cross-cultural research and describes current controversies, including the appropriateness of bringing to bear Western structures of mental health and psychiatric diagnosis to non-Western settings. It reports early lessons learned from the field regarding what might best constitute assistance within a foreign culture and where to place emphasis. It recommends becoming involved within the relief establishment.  相似文献   
90.
We describe a unique gait phenomenon of bent knees in 9 patients with idiopathic Parkinson disease (mean age, 73.1 +/- 11.1 years), 3 of whom also manifested tiptoeing. The bent-knee posture appeared only during ambulation; in the recumbent position, full or nearly full extension was possible in all patients. The abnormality emerged after long-standing disease (6-23 years from onset) and failed to respond to dopaminergic treatment. Most of the patients also had bent spine (camptocormia). The pathogenesis of these phenomena are unknown, but they might represent a rare type of dystonia.  相似文献   
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