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排序方式: 共有470条查询结果,搜索用时 15 毫秒
71.
O Al‐Saeed M Ismail RP Athyal M Rudwan S Khafajee 《Journal of Medical Imaging and Radiation Oncology》2009,53(4):366-372
T1‐weighted fluid‐attenuated inversion recovery (FLAIR) sequence is a relatively new pulse sequence for intracranial MR imaging. This study was performed to compare the image quality of T1‐weighted FLAIR with the T1‐weighted FSE sequence. Twenty patients with brain lesions underwent T1‐weighted fast spin‐echo (FSE) and T1‐weighted FLAIR during the same imaging session. Four quantitative and three qualitative criteria were used to compare the two sequences after contrast. Two of four quantitative criteria pertained to lesion characteristics: lesion to white matter (WM) contrast‐to‐noise ratio (CNR) and lesion to cerebrospinal fluid (CSF) CNR, and two related to signals from normal tissue: grey matter to WM CNR and WM to CSF CNR. The three qualitative criteria were conspicuousness of the lesion, the presence of image artefacts and the overall image contrast. Both T1‐weighted FSE and FLAIR images were effective in demonstrating lesions. Image contrast was superior in T1‐weighted FLAIR images with significantly improved grey matter‐WM CNRs and CSF‐WM CNRs. The overall image contrast was judged to be superior on T1‐weighted FLAIR images compared with T1‐weighted FSE images by all neuroradiologists. Two of three reviewers considered that the FLAIR images had slightly increased imaging artefacts that, however, did not interfere with image interpretation. T1‐weighted FLAIR imaging provides improved lesion‐to‐background and grey to WM contrast‐to‐noise ratios. Superior conspicuity of lesions and overall image contrast is obtained in comparable acquisition times. These indicate an important role for T1‐weighted FLAIR in intracranial imaging and highlight its advantage over the more widely practiced T1‐weighted FSE sequence. 相似文献
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Human red cells (RBCs) were collected in CPDA-1 and then freeze-dried in lyoprotective solution. The lyophilized RBCs were then stored at -20 degrees C for 7 days. At the end of the storage period, the lyophilized RBCs were rehydrated and washed in dextrose saline. The washed, reconstituted, lyophilized RBCs were resuspended in final wash solutions of ADSOL, CPDA-1, or a special additive solution containing glucose, citrate, phosphate, adenine, and mannitol, and then they were stored at 4 degrees C for an additional 7 days. The main purpose of this study was to determine whether human RBCs can be lyophilized in such a manner that normal metabolic, rheologic, and cellular properties are maintained during rehydration and subsequent storage in standard blood bank preservative solutions. Our results show that reconstituted, lyophilized RBCs maintained levels of ATP, 2,3 DPG, lactate, and cellular properties that are equal to or better than those in control nonlyophilized RBCs stored for a comparable period in CPDA-1. Reconstituted, lyophilized RBCs stored at 4 degrees C after rehydration also show better maintenance of ATP, 2,3 DPG, and lactate than do control RBCs stored in the same preservative solutions for comparable periods. 相似文献
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目的:观察胸腰段椎弓根CT测量在椎弓根螺钉内固定中的作用,寻找一种个体化椎弓根螺钉置入的方法。方法:选择1999-02/2006-03河北工程大学附属医院收治的T12和/或L1段骨折患者59例,行螺旋CT检查及图像三维重建,重建结束后,得到胸腰段标本的三维图像,通过旋转和切割进行图像处理并测量,模拟出T11~L2的椎弓根形态,根据CT测量椎弓根的实际投照点进行调整,即横断面上椎弓根轴线与矢状位上椎弓根轴线的交点,在确定进钉点时选择下关节突为参照物,选用合适直径的螺钉进行植钉,植入螺钉后,连接棒或板系统。结果:262个椎弓根行植钉术,242个完全在椎弓根内,仅有20个螺钉穿透椎弓根皮质。术后平均随访16.1个月,均无临床并发症的发生,Frankel平均增加1.4级。术后有2例患者出现断钉(3枚),1例患者出现断棒,所植入的螺钉与机体生物相容性好,无不良反应的发生。结论:利用三维CT测量的数据辅助,严格按照个体化的椎弓根的轴线方向植钉,在置钉时应考虑到螺钉本身直径的因素,可以提高植钉的成功率。 相似文献
76.
TP Jain DN Srivastava RP Sahu S Thulkar S Sharma S Mittal V Dadhwal 《Journal of Medical Imaging and Radiation Oncology》2007,51(3):246-252
The aim of this study was to determine the effectiveness of uterine artery embolization (UAE) as a primary treatment method in treatment of symptomatic fibroids, whether there are any preembolization MRI characteristics of fibroid predictive of reduction in volume and assess reduction in uterine and dominant fibroid volumes using ultrasound (US) and MRI. Study was carried out in total of 32 patients aged 25–49 years (mean 40.9 years). Uterine and dominant fibroid volume were determined using US and MRI before UAE, MRI and US at 3 months and US alone at 6 and 12 months post‐UAE, supplemented by clinical evaluation at interval of 3, 6 and 12 months. Procedure was carried out through unilateral femoral puncture using poly vinyl alcohol (PVA) particles 355–500 μm in size. All 32 patients had successful procedures. Overall, 25 patients responded, giving a clinical success rate of 78.12%. Mean reduction in volume of uterus and fibroid was 33 and 59.7% and 48.9 and 75.5% on US at 3 and 12 months respectively, and 33.3 and 58.6% on MRI at 3 months. Volume reduction on US and MRI at 3 months was highly correlative. There was no statistical difference in size reduction in volume of fibroids, which were hypointense or hyperintense on T2‐weighted image (T2WI) on pre‐UAE MRI. Uterine artery embolization leads to good technical success and fibroid volume reduction. Ultrasound alone may be used for follow up of patients post‐UAE. Preprocedure signal characteristics on T2WI are not predictors of volume reduction after UAE. 相似文献
77.
敏定偶用于35岁以上妇女的疗效、安全性和周期控制 总被引:11,自引:0,他引:11
<正> 口服避孕药在投放市场之初,应用于各种年龄段的妇女。然而资料显示早期使用的高剂量口服避孕药会增加心肌梗塞的发病率;在1975年,美国食品药物管理局(FDA)不建议40岁以上的妇女服用避孕药,对30岁以上的吸烟妇女建议她们要么停止吸烟要么改换避孕方式。随着研究的进一步深入及低剂量口服避孕药的问市,已证实任何年龄的非吸烟 相似文献
78.
Storb R; Prentice RL; Banaji M; Witherspoon RP; Sullivan KM; Stewart P; Sanders JE; Mason M; Doney K; Deeg J; Clift RA; Buckner CD; Appelbaum FR; Thomas ED 《Blood》1983,61(4):672-675
The present study in patients with aplastic anemia was undertaken to determine whether exposure of recipients to donor blood products 24 hr before preparation with cyclophosphamide (1) enhanced the rate of sustained engraftment of marrow from HLA-identical siblings as suggested by animal experiments, (2) increased the rejection rate, in particular in transfused patients who may already have been exposed to donor antigens by blood products, or (3) was of no relevance to the outcome of transplantation of marrow from HLA-identical siblings. One- hundred fifty-five patients were studied, of whom 78 received blood products from the marrow donor 24 hr before cyclophosphamide and 77 did not. A binary logistic regression analysis was applied to the data, simultaneously considering five previously known risk factors for rejection. Results showed that preceding transfusion of donor blood products had neither a significant beneficial nor detrimental effect on the incidence of sustained engraftment. 相似文献
79.
Intravenous gammaglobulin treatment of chronic idiopathic thrombocytopenic purpura 总被引:11,自引:0,他引:11
Bussel JB; Kimberly RP; Inman RD; Schulman I; Cunningham-Rundles C; Cheung N; Smithwick EM; O'Malley J; Barandun S; Hilgartner MW 《Blood》1983,62(2):480-486
High-dose intravenous gammaglobulin (IVIgG) was given to 12 children and adults with chronic idiopathic thrombocytopenic purpura (ITP) to avoid splenectomy or because they either failed to respond to or required maintenance with high doses of steroids and/or immunosuppressives. The average platelet count increase to initial therapy was 239,500/microliters (range 23,000-790,000). A concomitant IgG Fc receptor blockade, measured by IgG-sensitized 51Cr-labeled autologous erythrocytes, was seen in 11 of 11 patients tested, both splenectomized and not splenectomized, lasting 3-4 wk. Six or more months after treatment, 2 children are in remission, 2 children and 2 adults are stable requiring no therapy with platelet counts of approximately 50,000 and 30,000, respectively, 3 children require maintenance IVIgG therapy at 2-10-wk intervals, and 1 child and 2 adults have become refractory to further IVIgG. Splenectomy was not performed in 4 children. Two adults were able to discontinue daily prednisone. The 3 patients who became unresponsive to Swiss Red Cross gamma-globulin (IgSRK) therapy did so in conjunction with a markedly elevated platelet-associated IgG and IgM. Serum IgM increased an average of 103 mg/dl after the IVIgG infusions. No significant side effects were seen. 相似文献
80.