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排序方式: 共有797条查询结果,搜索用时 31 毫秒
1.
Intracranial circulation: pulse-sequence considerations in three- dimensional (volume) MR angiography 总被引:2,自引:0,他引:2
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
2.
Paediatric dacryocystorhinostomy 总被引:1,自引:0,他引:1
KN Hakin FRCS FRCOphth TJ Sullivan FRACO FRACS A Sharma FCOphth † RAN Welham FRCS FCOphth † 《Clinical & experimental ophthalmology》1994,22(4):231-235
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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Factors influencing women to undergo screening mammography 总被引:2,自引:0,他引:2
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Intrascrotal adenomatoid tumors 总被引:1,自引:0,他引:1
T L Tammela T J Karttunen H P M?k?r?inen P A Hellstr?m S I Mattila M J Kontturi 《The Journal of urology》1991,146(1):61-65
Adenomatoid tumors are regarded as uncommon neoplasms of the paratesticular tissues, probably of mesothelial origin. The majority of cases reported have involved the epididymis. We report our experience with 8 cases of testicular tumors and 11 of epididymal adenomatoid tumors during a 13-year period, and review the relevant literature. The incidence of adenomatoid tumors relative to all tumors in the testis was 6.9% (8 of 116), exceeding that of Leydig cell tumors, which were previously believed to be the most common benign testicular neoplasms. The adenomatoid tumors included 38% epididymal tumors (11 of 29). The clinical course of the tumors was benign, without recurrences. Local excision is regarded as the treatment of choice for epididymal and testicular adenomatoid tumors. 相似文献
7.
H Autio-Harmainen T Karttunen M Apaja-Sarkkinen K Dammert L Risteli 《The American journal of surgical pathology》1988,12(6):469-476
Immunohistochemical staining was used to demonstrate basement membrane (BM) laminin and type IV collagen in eight cases of Kaposi's sarcoma (KS). These KS were not associated with AIDS and represented different histological stages of the disease: patch (three cases), plaque (one case), and nodule (four cases). Nine cases of benign angiogenic lesions, five of blood vessel origin, and four of lymphatic vessel origin were also studied. An early event in vascular proliferation at the patch stage of KS was an intersection of dermal collagen bundles and the appearance of granular BM material around this space. With the increase of amount and linear arrangement of BM material, well-defined capillaries were formed. Two types of capillary were found in KS lesions. One showed morphological features of blood capillaries, with a round lumen; thick, continuous BM, and occasional pericytes in the wall. The other included irregularly shaped vessels with thin, often disrupted BMs; thus these capillaries morphologically resembled lymphatic capillaries. BM staining also clearly revealed the vascular nature of the nodular lesions of KS, which were composed of a network of slit-like spaces surrounded by BMs. The solid tumor cell areas were sparse; they were composed of spindle-shaped cells surrounded by thin, interrupted basal laminae. By using antibodies against human laminin and human type IV collagen, it was also possible to demonstrate thin, widely disrupted BMs subendothelially in normal dermal lymphatic capillaries. Typically, the BMs in lymphangiomas and lymphangiectasias were continuous and more clearly defined. 相似文献
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Aaro Leinonen Topi Siniluoto Markku Päivänsalo Ari Karttunen Matti I. Kairaluoma Ilkka Suramo 《European radiology》1993,3(3):213-218
Nineteen patients with 49 symptomatic non-neoplastic non-parasitic simple hepatic cysts were subjected to ultrasonographically guided percutaneous aspiration and temporary injection of 99% ethanol into the cyst. Small cysts were treated twice, the large ones three times at the same sitting. The volume of alcohol per injection varied from 20 to 100 ml, depending on the size of the cyst. A cure was usually achieved with one ethanol sclerotherapy treatment. Only minor side effects such as transient pain and temperature elevation occurred. Forty-seven of the 49 cysts could be treated adequately, and did not recur during a follow-up period af 12–40 months. The results indicate that aspiration an and ethanol sclerotherapy is the treatment of choice in patients with symptomatic non-neoplastic simple hepatic cysts or polycystic liver disease.
Correspondence to: A. Leinonen 相似文献