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21.
Nancy P. Caraway Gregg A. Staerkel Christina V. Fanning Datla G. Varma Raphael E. Pollock 《Diagnostic cytopathology》1994,11(3):255-261
The gross and microscopic appearances of aspirates from ten intramuscular myxomas are reported. The specimens were obtained from seven women and three men, ages 43 to 75, who had tumors involving the muscles of the thigh (7), upper arm (2), and forearm (1). Magnetic resonance (MR) imaging performed in six of the ten cases revealed well-defined, sharply demarcated tumors exhibiting low signal intensity relative to muscle on the T1-weighted images. The tumors were hyperintense to muscle on T2-weighted images. All aspirated tissues were clear, tenacious, and viscous. Smears contained few spindled and histiocytoid cells in an abundant mucoid background. Spindle cells demonstrated long cytoplasmic processes that in areas intertwined to form fibrillar tangles. Nuclei were oval to spindled with fine chromatin and inconspicuous nucleoli. Capillaries were sparse with simple (nonplexiform) branching. The differential diagnosis of myxoid lesions of the extremities includes benign entities such as myxoid schwannoma and neurofibroma, mesenchymal repair, and ganglion cyst, as well as malignant neoplasms such as myxoid liposarcoma, fibrosarcoma, malignant fibrous histiocytoma, and extraskeletal chondrosarcoma. The findings of this study revealed that, although the cytologic features were suggestive of intramuscular myxoma, a definitive diagnosis was often difficult, owing to scant cellularity and lack of distinctive cytologic features. The MR imaging findings may be utilized as an adjunct to the cytologic features to more confidently suggest a diagnosis of intramuscular myxoma. Diagn Cytopathol 1994;11:255–261. © 1994 Wiley-Liss, Inc. 相似文献
22.
Thorascopic coronary surgery has achieved great progress in the past few years. After computer-directed instrument systems were introduced, which enabled high precision and expanded mobility in close quarters, the limitations of conventional endoscopic instruments were largely overcome. Employing modern surgical telemanipulators and endoscopic stabilizers, entirely endoscopic myocardial revascularization of the anterior wall is being successfully performed during off-pump surgery. Longer operating times and conversion rates in about one-fifth of the patients due to technical and anatomical limitations still restrict the use of these new surgical techniques compared to conventional surgery. Development of further technologies and integration of video-assisted navigation systems will broaden the application of computer-assisted instrument systems in the near future. 相似文献
23.
Ernst Heinrich; Ohshima Hiroshi; Bartsch Helmut; Mohr Ulrich; Reichart Peter 《Carcinogenesis》1987,8(12):1843-1845
In order to evaluate the effect of concurrent administrationof areca nut and sodium nitrite, a long-term feeding study wasconducted with 120 Syrian hamsters. The animals were dividedinto four treatment groups, each consisting of 15 males and15 females, and received 2 g/kg diet of sodium nitrite (groupI), 20 g/kg diet of powdered areca nut (group II), 2 g/kg dietof sodium nitrite plus 20 g/kg diet of areca nut (group III)or powdered diet only (group IV) throughout their lifetime.Urine samples from all groups were analysed for N-nitrosonipecoticacid (NNIP), a major urinary metabolite of areca-nut-derivednitrosamines. NNIP was only detected in the urine of hamstersfed nitrite plus areca nut (concentration: 1.9±0.9 ng/mlurine), indicating that areca nut alkaloids underwent in vivonitrosation to form arecanut-specific nitrosamines. The totaltumour response was not significantly elevated in groups IIand III. Hamsters of group III had a markedly, but also insignificantlyhigher frequency of malignant tumours than those of the othergroups, with a statistically significant increase in malignantlymphomas in the males. Although limited by the low number ofanimals per group, these results indicate that exposure to nitritetogether with areca nut constituents appears to enhance therisk of developing malignancies. 相似文献
24.
Thirty cigarette smokers and 25 non-smoking controls, all men were evaluated by history, physical examination and simple spirometry. The history and physical examination were not of much use in predicting airflow obstruction. Forced mid-expiratory flow (FEF 25-75%) was abnormally low in 23 of the 30 subjects, while forced expiratory volume in 1 second (FEV1) and FEV1/FVC (forced vital capacity) were less sensitive. Thus simple spirometry is a useful screening tool to detect early airflow obstruction even when it is clinically undetectable. 相似文献
25.
Three-dimensional reconstruction in routine computerized tomography of the skull and spine. Experience based on 161 cases. 总被引:1,自引:0,他引:1
L Bonnier K Ayadi A Vasdev G Crouzet B Raphael 《Journal of neuroradiology. Journal de neuroradiologie》1991,18(3):250-266
Three-dimensional (3D) reconstruction in routine computerized tomography (CT) presupposes that the referring clinicians are motivated, software programs are of good quality, a second working console is available and manipulations are made by experienced persons. Maxillofacial surgery is the main, conventional indication, but the method is also used to plan the surgical treatment of craniofacial malformations and that of injuries and tumours. 3D reconstruction cannot replace a thorough analysis of the acquisition sections since its spatial definition is not as good as theirs. Without competing with pure research-work, a number of applications remain in the realm of speculative imaging, but it cannot be denied that 3D reconstruction has an interesting potential for teaching. 相似文献
26.
R A Mohr 《Health services management research》1994,7(2):79-90
A causal model of the institutionalization process is presented. Path analysis and logistic regression are performed on NHIS Longitudinal Study of Aging data. Based on initial analysis, the model is revised and re-evaluated. Convergent results support significance for four of five proposed predictors. Results are similar for men and women. Findings suggest unidentified factors are important to nursing home admission and that attention should be given to the process of decision-making that leads to admission. 相似文献
27.
28.
Preoperative evaluation of pulmonary risk factors 总被引:3,自引:0,他引:3
29.
Nimodipine treatment in poor-grade aneurysm patients. Results of a multicenter double-blind placebo-controlled trial 总被引:4,自引:0,他引:4
K C Petruk M West G Mohr B K Weir B G Benoit F Gentili L B Disney M I Khan M Grace R O Holness 《Journal of neurosurgery》1988,68(4):505-517
A multicenter, randomized placebo-controlled double-blind trial of nimodipine in poor-grade aneurysm patients was carried out in 17 Canadian hospitals. Of 188 patients enrolled in the trial, 32 were excluded for protocol violations and two were excluded due to statistical considerations, leaving 154 patients for valid outcome analysis. Nimodipine treatment was associated with a significantly better outcome (p less than 0.001): 21 (29.2%) of 72 nimodipine-treated patients had a good outcome at 3 months after subarachnoid hemorrhage (SAH) compared to eight (9.8%) of 82 placebo-treated patients. Delayed ischemic deficits from vasospasm alone were significantly less frequent in the nimodipine group (p less than 0.05) with permanent deficits occurring in five nimodipine-treated patients (6.9%) and in 22 placebo-treated patients (26.8%). Improvement in the good outcome rate and reduction in delayed ischemic deficits from vasospasm alone occurred in both Grade 3 and 4 patients, with no difference between nimodipine- and placebo-treated patients being found in Grade 5 patients. Repeat angiography after Day 4 was carried out in 124 patients. There was no significant difference in the incidence of moderate or severe diffuse spasm, which was seen in 64.3% of nimodipine-treated patients and 66.2% of placebo-treated patients. The authors conclude that nimodipine treatment in poor-grade patients with SAH results in an increase in the number of good outcomes and a reduction in the incidence of delayed neurological deterioration due to vasospasm. This effect occurs by a mechanism other than prevention of large-vessel spasm as visualized on angiography. 相似文献
30.