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61.
62.
邓天权 《生物医学工程学杂志》1991,8(4):299-304
本文提出并研究了一种新型的电磁热疗系统-H面号角环形相控阵系统。推导出了适应性广的理论公式。以肺部CT图为模型,用矩量法计算得到了胸腔横断面内电场分布及吸收功率分布的计算机数值结果。结果表明,在200MHz的电磁波辐射下,适当调节阵列各单元的相位,振幅和位置,肺部肿瘤可得到优化的选择性加热,从而达到最佳的热疗效果。 相似文献
63.
David C. Dahlin M.D. Franco Bertoni M.D. John W. Beabout M.D. Mario Campanacci M.D. 《Skeletal radiology》1984,12(4):263-269
In a review of cases of fibrous cartilaginous dysplasia of bone, five of fibrocartilaginous lesions were found to be different in clinical behavior and radiographic and morphologic features from the others. We have named these previously undescribed tumors fibrocartilaginous mesenchymomas with low-grade malignancy in the fibrous elements.Dr. Bertoni is a visiting surgical pathologist from the Servizio di Anatomia ed Istologia Patologica, Bologna, Italy 相似文献
64.
65.
Lisa M. Rooper Lester D. R. Thompson Jeffrey Gagan Bahram R. Oliai Ilan Weinreb Justin A. Bishop 《Head and neck pathology》2021,15(1):179
Intraductal carcinoma (IDC) is a rare salivary gland tumor that is considered analogous to ductal carcinoma in-situ of the breast, demonstrating a complex neoplastic epithelial proliferation surrounded by a continuous layer of presumed non-neoplastic myoepithelial cells. It is subcategorized into intercalated duct, apocrine, and hybrid subtypes based on morphologic and immunohistochemical features, with frequent NCOA4-RET and TRIM27-RET fusions, respectively, seen in intercalated duct and hybrid tumors. However, as an expanding clinicopathologic spectrum of IDC has been documented, controversy has emerged as to whether this tumor type is best defined by its intraductal growth pattern or distinctive molecular and immunophenotypic differentiation. Here, we further explore the nature of IDC by evaluating four cases that arose within intraparotid lymph nodes. These intercalated-duct phenotype tumors with diffuse S100 protein expression demonstrated a crowded and complex epithelial proliferation arranged in cystic, cribriform, and micropapillary architecture, surrounded by an intact myoepithelial cell layer, and were completely intranodal. Of two tumors with tissue available for molecular analysis, one demonstrated a NCOA4-RET fusion and one harbored a STRN-ALK fusion that is novel to IDC. Not only does the intranodal presence of IDC present a challenging differential diagnosis, but the complex nature of this proliferation within lymph node tissue raises questions as to whether the myoepithelial component of IDC is actually non-neoplastic in nature. Furthermore, identification of a STRN-ALK fusion expands the genetic spectrum of IDC and adds to evidence of an emerging role for ALK in salivary gland tumors. Further attention to the nature of the myoepithelial cells and documentation of alternate fusion events in IDC may inform continued discussion about its appropriate classification. 相似文献
66.
Bengi Balci Alp Yildiz Sezai Leventoğlu Bulent Mentes 《World journal of gastrointestinal surgery》2021,13(11):1327-1337
Retrorectal or presacral tumors are rare lesions located in the presacral area and considered as being derived from multiple embryological remnants. These tumors are classified as congenital, neurogenic, osseous, inflammatory, or miscellaneous. The most common among these are congenital benign lesions that present with non-specific symptoms, such as lower back pain and change in bowel habit. Although congenital and developmental tumors occur in younger patients, the median age of presentation is reported to be 45 years. Magnetic resonance imaging plays a crucial role in treatment management through accurate diagnosis of the lesion, the evaluation of invasion to adjacent structures, and the decision of appropriate surgical approach. The usefulness of preoperative biopsy is still debated; currently, it is only indicated for solid or heterogeneous tumors if it will alter the treatment management. Surgical resection with clear margins is considered the optimal treatment; described approaches are transabdominal, perineal, combined abdominoperineal, and minimally invasive. Benign retrorectal tumors have favorable long-term outcomes with a low incidence of recurrence, whereas malignant tumors have a potential for distant organ metastasis in addition to local recurrence. 相似文献
67.
国人男性椎管的测量与观察 总被引:2,自引:0,他引:2
本文对广西出土的113例男性干燥椎骨的椎孔,进行了矢径、横径的测量和形态观察。椎孔的矢、横径在壮族(30例),汉族(57例)间无显著差异(P>0.05)。在C_(3~6)椎骨水平,推管的矢径和形态与脊髓的外形不一致,矢径于该处形成生理性狭窄,以C_4处为最小(12.92mm)。除C_1外,椎管的形态可分为4型:Ⅰ型圆型;Ⅱ型三角型;Ⅲ型过渡型;Ⅳ型不整型。 C_(1,2)椎管的形状为圆型,向下至C_6,通过半圆形逐步过渡到三角形(C_6占81.31%);再向下至T_6,三角形通过蛤形和多边形又逐渐过渡为圆形(T_6占84.76%);再向下至L_5,又通过蛤形逐渐过渡为三角型(L_5占99%)。从L_3至L_5,三角形椎孔有逐步通过钟形向三叶形过渡的趋势。三叶形腰椎管占5.02%。本文结果支持Eisenstein的观点,认为三叶形结构是一种普通的、非病理性的现象,与年龄增长、骨赘或椎孔狭窄无关,这或许是一种正常的发育性变异。 相似文献
68.
I. G. Bogdanov V. T. Velichkov A. I. Gurevich P. G. Dalev Academician M. N. Kolosov V. P. Mal'kova I. B. Sorokina L. N. Khristova 《Bulletin of experimental biology and medicine》1977,84(6):1750-1753
The antitumor action of the substance blastolysin, the main components of which are glycopeptide fragments from the cell wall ofLactobacillus
bulgaricus, was studied. Blastolysin exhibits a specific antitumor effect against sarcoma S-180, leukemia P-388, plasmacytoma MOPC-315, adenocarcinoma AKATOL, melanosarcoma B-16, carcinoma LLC, and spontaneous tumors of mice. It has low toxicity, does not depress hematopoiesis, and in the character of its action on tumor tissue it differs essentially from known chemotherapeutic preparations.M. M. Shemyakin Institute of Bioorganic Chemistry, Academy of Sciences of the USSR, Moscow. Scientific-Production Laboratory of Biologically Active Substances, Sofia, Bulgaria. Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 84, No. 12, pp. 709–712, December, 1977. 相似文献
69.
Bernd Niederhagen N. Leipner S. Bergé J.-J. von Lindern T. Appel 《Mund-, Kiefer- und Gesichtschirurgie》2000,4(4):217-221
Problem: There is a lack of clear criteria for the use of MR and CT in the diagnosis of head and neck cancer – some of it
is even contradictory. The results of this study should lead to the establishment of more clear criteria. Patients: 165 patients
suffering from head and neck tumors were subjected to a total of 463 CT and 197 MRI examinations. Results: The CT and MRI
staging corresponded in 67% and 60% of the oropharynx tumors, respectively, with the clinical findings. In the case of oral
cavity tumors, the clinical TNM stages were identical with CT and MRI results in 50% and 43% of cases, respectively. In the
case of lymphatic node staging, the frequency of error was slightly higher using MRI, at 27%, compared with the CT rate of
22%. In the evaluation of cervical lymphatic nodes, CT proved to be more sensitive attaining 78% compared to the MRI rate
of 69%. Conclusion: The results provide clear indications as to the MRI and CT examinations. Primary preoperative screening
and post-therapeutic aftercare should be assessed using CT, as should lymphatic node diagnosis in the neck area. In the case
of special problems such as, for example, the relevant bone and periostium infiltration, MR should be considered as a supplementary
examination at a second stage.
相似文献
70.
后半规管阻塞前后豚鼠前庭及耳蜗功能的动态变化 总被引:6,自引:1,他引:5
目的 探讨机械性后半规管阻塞前后豚鼠前庭和耳蜗功能的动态变化。方法 采用20只豚鼠建立单侧后半规管阻塞的动物模型,观察手术前后眼震电图,听性脑干反应,耳声发射等变化。结果 术后第1天,第3天豚鼠正弦摆动刺激术侧眼震反应,明显减术,术后第5天起双侧眼震恢复正常。术后早期ABR阈值一度升高,第5天达高峰,ABR阈值平均升高4.5dB。DPOAE反应幅度无明显改变。结论 后半规管阻塞能选择性地消除后半规 相似文献