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61.
眼球孤立性脉络膜血管瘤的HR-MRI表现 总被引:4,自引:0,他引:4
目的 探讨眼球孤立性脉络膜血管瘤的高分辨率磁共振 (HR MRI)影像学特征 ,进一步提高诊断水平。资料与方法 回顾性分析诊断明确的孤立性脉络膜血管瘤 16例共计 17个病灶的位置、数目、形态、大小、MRI信号、强化情况、有无合并视网膜脱离及有无视神经和眼外侵犯等。所有病例均行HR MRI及增强扫描 ,部分病例行脂肪抑制。结果 17个病灶中的 16个呈扁丘状位于眼球内壁的后极。 15个病灶厚度 <5mm ,平均厚度为2 .9mm。病灶边缘清晰 ,T1WI上呈轻度高信号者 16个 ,T2 WI上呈等信号者 15个 ,增强扫描显著强化者有 12个。 3例合并视网膜脱离 ,在T2 WI上多呈等信号 ,T1WI上呈轻度高信号者 ,均无强化。无视神经及眼外侵犯病例。结论 94 %孤立性脉络膜血管瘤的HR MRI表现具有特征性 ,表现为位于眼球内壁后极的较小、基底较宽、边缘清晰的扁丘状病灶。其T1WI信号高于玻璃体 ,T2 WI信号等于玻璃体 ,增强扫描瘤体显著强化。明确其HR MRI影像学特征有助于临床与恶性葡萄膜黑色素瘤相鉴别 ,避免不必要的眼球摘除 相似文献
62.
ISAO HARA SATOKO HIKOSAKA HIROSHI ETO HIDEAKI MIYAKE YUJI YAMADA TOSHINORI SOEJIMA KAZURO SUGIMURA SADAO KAMIDONO 《International journal of urology》2004,11(8):678-682
We report on two cases of women with locally advanced squamous cell carcinoma of the urethra. Patient 1 also displayed regional lymph node metastasis. Treatment comprised combined radiotherapy to 60 Gy and chemotherapy with 5-fluorouracil and cisplatin. Complete response was obtained in both patients, including the inguinal lymph nodes of Patient 1. Patient 1 experienced recurrent inguinal lymph node metastasis on the contralateral side at 42 months after initial treatment, and the same treatment was performed followed by surgical excision. Both patients remain alive with no evidence of disease, at 12 months after recurrence in Patient 1, and at 27 months after treatment in Patient 2. 相似文献
63.
Kemal Yucesoy Iman Feiz-Erfan Robert F. Spetzler Patrick P. Han Stephen Coons 《Skull base》2004,14(3):169-173
A 42-year-old female presented with subarachnoid hemorrhage (SAH), presumably from a radiation-induced anterior communicating artery aneurysm. Six years earlier, she had undergone radiation treatment for an optic glioma that was diagnosed based on imaging criteria. The aneurysm was successfully clipped, and the optic glioma was biopsied to verify the diagnosis histologically. Radiation-induced cerebral aneurysms often manifest with a fatal SAH. These aneurysms typically develop in the field of radiation and are diagnosed a mean of 8.52 years after radiation. Rarely, the aneurysm sac thromboses spontaneously. Clipping or coiling of the aneurysm can be an effective treatment. 相似文献
64.
Effect of surface conditioning methods on the bond strength of luting cement to ceramics 总被引:9,自引:0,他引:9
OBJECTIVES: This study evaluated the effect of three different surface conditioning methods on the bond strength of a Bis-GMA based luting cement to six commercial dental ceramics. METHODS: Six disc shaped ceramic specimens (glass ceramics, glass infiltrated alumina, glass infiltrated zirconium dioxide reinforced alumina) were used for each test group yielding a total number of 216 specimens. The specimens in each group were randomly assigned to one of the each following treatment conditions: (1) hydrofluoric acid etching, (2) airborne particle abrasion, (3) tribochemical silica coating. The resin composite luting cement was bonded to the conditioned and silanized ceramics using polyethylene molds. All specimens were tested at dry and thermocycled (6.000, 5-55 degrees C, 30 s) conditions. The shear bond strength of luting cement to ceramics was measured in a universal testing machine (1 mm/min). RESULTS: In dry conditions, acid etched glass ceramics exhibited significantly higher results (26.4-29.4 MPa) than those of glass infiltrated alumina ceramics (5.3-18.1 MPa) or zirconium dioxide (8.1 MPa) (ANOVA, P<0.001). Silica coating with silanization increased the bond strength significantly for high-alumina ceramics (8.5-21.8 MPa) and glass infiltrated zirconium dioxide ceramic (17.4 MPa) compared to that of airborne particle abrasion (ANOVA, P<0.001). Thermocycling decreased the bond strengths significantly after all of the conditioning methods tested. SIGNIFICANCE: Bond strengths of the luting cement tested on the dental ceramics following surface conditioning methods varied in accordance with the ceramic types. Hydrofluoric acid gel was effective mostly on the ceramics having glassy matrix in their structures. Roughening the ceramic surfaces with air particle abrasion provided higher bond strengths for high-alumina ceramics and the values increased more significantly after silica coating/silanization. 相似文献
65.
66.
S. E. Greenwald C. E. Collino C. L. Berry 《Medical & biological engineering & computing》1988,26(5):497-502
An in vitro method for obtaining pressure/volume curves from the lungs of small animals is described. The excised lungs were
inflated and deflated with saline or air by a motor-driven syringe controlled by a microcomputer. The computer was programmed
to display the curves in real time, correcting when necessary for the compressibility of air in the system. Volume compliance
(K=dV/dP×1/V) was calculated by differentiating a polynomial fitted to the measured pressure/volume points. Repeatable curves
were obtained from mice aged 24h (body weight 1·3±0·14g (SD), residual lung volume 8·43±1·5 μl (SD). A nonlinear decrease
in differential compliance (K=dV/dP×1/V) with increasing strain was observed while the ratio Ksaline/Kair increased from 2·5 to 10 over the range of strains investigated (ε=1–5). The relative surface tension (calculated from the
difference between the pressures required to inflate the air and saline-filled organs to a given volume) increased exponentially
with increasing volume. We conclude that it is now possible to obtain reproducible pressure/volume curves for lungs with a
residual volume of less than 10 μl, from animals weighing approximately 1·5 g and, from these curves, estimate airway compliance
and surface tension. 相似文献
67.
5名电离辐射事故患者外周血T细胞T细胞抗原受体、T细胞分化抗原决定簇-3效应的研究 总被引:1,自引:0,他引:1
文中报道了5名事故性急性骨髓型放射病患者照后2.5和3.5年外周血T淋巴细胞T细胞受体(TCR)基因,TCR、T细胞分化抗原决定簇-3(CD_3)表达与TCR/CD_3复合物功能的辐射效应.发现5名患者于照后2.5年,2名(5.2Gy和2.4Gy,55岁)于照后3.5年外周血T细胞应答抗CD3单抗刺激而增殖的能力尚未完全恢复;经同时用IL-2和抗CD_3单抗刺激,增殖能力比单用抗CD_3单抗刺激有所增强;后2名的外周血TCR、CD_3阳性细胞百分率一直低于正常对照和其他患者;并见一患者出现DNA重排杂交带型.本文并从TCR/CD_3在介导T细胞抗原刺激反应中的作用,电离辐射对TCR/CD_3复合物的影响,后果和意义等方面进行了讨论. 相似文献
68.
Iodine-125 interstitial irradiation for cerebral gliomas 总被引:3,自引:0,他引:3
69.
70.
Dr C. J. Whitters T. W. Macfarlane D. Mackenzie H. Moseley R. Strang 《Lasers in medical science》1994,9(4):297-303
Pulsed Nd-YAG laser irradiation of bacteria has been suggested as a possible means of treating contaminated intra-oral sites
although relatively few studies have been conducted. In this investigation, the antimicrobial activity of a pulsed Nd-YAG
laser was assessed in vitro for a range of oral bacteria using several pulse energies and exposure durations. Pure cultures
of each organism were lased in saline suspensions followed by standard colony counting techniques for test and control samples.
Microbial inhibition was found to be organism-dependent and varied with energy dose and pulse energy. For all nine test species
120-mJ laser pulses proved more efficient than 80-mJ pulses, with 99.9% kills compared with around 90% kills after exposure
to 1800 pulses. These killing activity levels compare favourably with those achieved with other lasers in vitro. 相似文献