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941.
942.
943.
OBJECTIVES: To evaluate the accuracy of presumption of the primary sites of neck lymph node metastases based on fine needle aspiration cytology. STUDY DESIGN: Retrospective review of 133 cytologically diagnosed carcinomas with known primary sites and sufficient cellularity during a three-year period. Presumption of primary sites was carried out on randomized samples six months later. RESULTS: Some cytomorphologic characteristics are useful for presumption of primary sites, such as monolayered papillary fronds with intranuclear cytoplasmic inclusions in thyroid papillary carcinoma; large, polygonal, keratinized cells with a low nuclear/cytoplasmic ratio and anucleated squames in perioral cancers; and numerous naked nuclei, destroyed nuclei and marked lymphocytic infiltrates in nasopharyngeal cancer. The accuracy rate of presumption of primary sites was 100% (6/6) in thyroid papillary carcinoma, 83% (24/29) in perioral cancer and 77% (26/34) in nasopharyngeal cancer but low in other malignancies. CONCLUSION: Utilizing cytomorphologic characteristics, a presumption of primary sites of neck lymph node metastases could be achieved for the thyroid, perioral areas and nasopharynx. 相似文献
944.
JS Plotkin M Njoku CD Howell PC Kuo JW Lim JM Laurin ST Bartlett LB Johnson 《Canadian Metallurgical Quarterly》1997,3(4):468-470
The establishment of a new liver transplant program requires enormous planning and resources. Extensive negotiations must take place to ensure institutional and departmental commitments to obtain the proper equipment, personnel, and other resources. The formation of a well-trained multidisciplinary team of physicians and nurses becomes the next step. Finally, ample time must be provided to adequately deploy resources, lobby referring physicians, recruit patients, and troubleshoot problems as they arise. 相似文献
945.
946.
PURPOSE: The clinicopathologic findings in 45 adult Chinese patients with primary small-intestinal lymphoma (PSIL) are described and compared with those in Western countries and in underdeveloped nations. The efficacy of combination chemotherapy is also assessed. PATIENTS AND METHOD: Six patients had immunoproliferative small-intestinal disease (IPSID) indicated by the presence of alpha-heavy chain protein (alpha-CP) in body fluids or tumor tissues. Thirty-nine patients had non-IPSID, including one with postrenal transplant lymphoma. Thirty-three non-IPSID patients received a minimum of four cycles of combination chemotherapy with cyclophosphamide, doxorubicin, vincristine, and prednisolone (CHOP). RESULTS: All IPSID patients presented with the clinical and laboratory features of severe intestinal malabsorption, and all had diffuse lymphoplasmacytic infiltration in the mucosa of the small bowel. Lymphomas were localized mainly in the jejunum and mesenteric nodes. The histologic subtypes were diffuse large cell in two, immunoblastic in three, and diffuse mixed in one. All patients responded poorly to chemotherapy, with a median survival duration of 10.5 months. The common presenting symptoms of the 39 non-IPSID patients included abdominal pain (90%), weight loss (31%), abdominal mass (26%), obstruction (26%), and perforation (23%). Diffuse large-cell and immunoblastic lymphomas constituted 82% of cases. Four patients had stage IE, 19 stage II 1E, and 16 stage 112E disease according to the Musshoff's criteria; 22 had bulky tumors and 19 had multiple tumors. The tumors were completely resected in 14 patients. Of 33 patients treated with combination chemotherapy, 73% achieved a complete remission. With a median follow-up duration of 90 months, there have been four relapses, with only one at the primary tumor site. The overall 5-year survival and disease-free survival rates for non-IPSID patients who were treated with chemotherapy were 59% and 54%, respectively. CONCLUSION: Intensive chemotherapy produces long-term disease-free survival in locally advanced non-IPSID PSIL. 相似文献
947.
A computer-aided analysis system has been established to calculate the equivalent inductance and resistance matrices for three-dimensional multiconductor interconnection structures. Based on partial element equivalent circuit theory, the interconnection structures are first decomposed into many straight segments which are of circular or rectangular cross sections but can be in arbitrary orientation. The resistances and partial inductances between all these segments are calculated using analytical integration and quadrature formulae. They are assembled into the desired equivalent impedance matrix by general network theory. Illustrative examples include the analysis for nonuniformly coupled transmission lines and the calculation for skin-effect impedances of transmission lines and three-dimensional structures. The numerical results are in good agreement with the measurement data and results in the literature 相似文献
948.
TT Kuo 《Canadian Metallurgical Quarterly》1994,25(3):319-323
An anterior mediastinal tumor resected from a 54-year-old man without paraneoplastic symptoms was found to be an unusual biphasic thymic tumor composed of carcinoid tumor in sarcomatous stroma characterized by fibrosarcoma-like spindle cells with areas of chondroid and osseous differentiation. Immunohistochemical and ultrastructural studies verified that the tumor described was a carcinoid tumor with divergent sarcomatoid differentiation rather than a mixed carcinoid tumor and sarcoma. The chondroid and osseous differentiations observed were unique features. This tumor is rare and provides an opportunity for understanding tumors with divergent components. The sarcomatoid transformation of thymic carcinoid tumor might denote highly malignant clinical behavior as illustrated by this case. 相似文献
949.
950.
CT Wang S Kubota T Kakuda CC Kuo TL Hsu M Onuma 《Canadian Metallurgical Quarterly》1998,60(2):253-255
The aim of this preliminary study was to investigate sleep-wake rhythm in active, healthy elderly people residing in their usual habitat. The subjects were thirty-five male volunteers within an age range of 65-95 for 3-4 days. We measured the sleep-wake rhythm of the subjects with an Actillume which is a combined wrist activity monitor and illumination recorder. Analysis of the Actillume recording showed that 24 of the 35 subjects (69%) kept continuous activity indicating good maintenance of wakefulness with high light exposure. The mean mesor of sleep-wake rhythm, however, significantly decreased in the older subjects (aged 80-95; n=15). 相似文献