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41.
Survivors of childhood acute lymphoblastic leukemia (ALL) treated with chemotherapy only are at risk for neurocognitive impairment. Regions of interest were identified a priori based on glucocorticoid receptor distribution, and sex‐stratified multivariable linear regression models were used to test associations between brain MRI morphology and total number of intrathecal injections, and serum concentration of dexamethasone and methotrexate. Compared with controls, ALL survivors have persistently smaller volumes in the bilateral cerebellum (P < 0.005), hippocampal subregions (P < 0.03), temporal lobe regions (P < 0.03), frontal lobe regions (P < 0.04), and parietal lobe regions (precuneus; P < 0.002). Long‐term problems with learning may be related to residual posttreatment brain differences.  相似文献   
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经皮椎体注入骨水泥治疗老年脊椎骨质疏松压缩性骨折   总被引:4,自引:0,他引:4  
目的:观察经皮椎体内注入骨水泥(聚甲基丙烯酸甲酯)治疗脊椎骨质疏松压缩性骨折的疗效。方法:自2005-06/2006-06吉林大学中日联谊医院骨科及大庆龙南医院骨科对35例40个椎体的骨质疏松压缩性骨折患者使用经皮椎体内注射骨水泥,行椎体成形术。成形材料:美国KYPHON公司生产的骨水泥,生产准许号:(GB/T19001-2000和YY/T0287-1996)。结果:35例患者均参加随访6个月。术后均未出现骨水泥外漏、脊髓或马尾神经损伤等并发症。35例患者中5例出现穿刺部位局部疼痛,服用镇痛药物后均缓解。疼痛完全消失25例,占71.4%;明显缓解8例,占22.6%;轻度缓解2例,占6.0%;无缓解0例。15例患者在术后72h内均能下床活动。术后未再发生压缩性骨折及疼痛。结论:经皮椎体注入骨水泥可以有效改善椎体骨质疏松压缩性骨折患者疼痛症状,随访6个月未出现充填剂不良性宿主反应,临床疗效较好。  相似文献   
43.
Amyloid involvement of the breast is infrequently reported and may have clinical and radiological features suspicious for a primary breast malignancy. We describe a case of amyloid of the breast in which asymptomatic mammographic findings were suspicious for locally recurrent disease in a patient with previously treated breast cancer.  相似文献   
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Serotonin causes a dose related (0.1-20 micrograms/kg i.v.) increase in mean arterial blood pressure (MAP) and heart rate in conscious sheep. Ketanserin (0.1 mg/kg per h i.v.) causes a decrease in blood pressure, and an increase in heart rate. In the presence of ketanserin, serotonin induced increases in MAP are attenuated, or abolished, but the increases in heart rate are enhanced. Ketanserin (10 mg/kg per h i.v.) attenuates or abolishes the increase in blood pressure induced by the alpha-adrenoceptor agonist phenylephrine in conscious sheep. When administered in the presence of the alpha-adrenoceptor antagonist prazosin, ketanserin (0.1 mg/kg per h i.v.) fails to induce a further hypotensive response. These data suggest that in the conscious sheep ketanserin exhibits predominantly alpha-adrenoceptor antagonism.  相似文献   
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SUMMARY 1. The effect of surgical denervation of the adrenal gland on ACTH-induced hypertension in the sheep has been examined. ACTH (80 iu/day) was administered for 5 days to eight sheep before and after bilateral surgical denervation of the adrenal.
2. In intact sheep, ACTH-induced hypertension is associated with a significant increase in cardiac output and heart rate. Adrenal denervation obtained by sectioning of the lumbar sympathetic and splanchnic nerves supplying the adrenal gland did not alter the magnitude or time course of the hypertension, or the increase in heart rate.
3. Adrenal denervation did not affect the increase in plasma sodium, the fall in plasma potassium, the initial urinary sodium retention, the increase in water turnover or the changes in blood corticosteroids which are seen during ACTH administration to intact sheep. However, in these adrenally denervated sheep ACTH treatment did not significantly change cardiac output.
4. This study suggests an important role for a factor or factors from the adrenal cortex in causing ACTH-induced hypertension.  相似文献   
49.
Vico  JJ; Larsen  CR 《Radiology》1979,131(3):636
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50.
SUMMARY BACKGROUND DATA: Previous studies have suggested a variety of factors that may affect the false negative (FN) rate for sentinel lymph node (SLN) biopsy in breast cancer. Because FN results are relatively rare, no prior studies have had sufficient sample size to allow detailed statistical analysis of factors predicting FN results. METHODS: Patients with clinical stage T1-2, N0 invasive breast cancer were enrolled in a prospective, multicenter study. All patients underwent SLN biopsy, followed by planned completion axillary dissection regardless of the SLN results, to assess the FN rate. SLN biopsy was performed using radioactive colloid injection in combination with isosulfan blue dye in 94% of cases. Dermal, subdermal, peritumoral, or subareolar radioactive colloid injection techniques were used at the discretion of each institution. Univariate and multivariate analyses were performed to identify factors associated with a FN result. RESULTS: SLNs were identified in 3870 of 4117 patients (94%). There were 1243 true positive, 2521 true negative, and 106 FN results. Age, histologic subtype, the number of non-SLN removed, tumor palpability, type of breast biopsy, and SLN injection technique were not significant factors. On multivariate analysis, tumor size <2.5 cm, upper outer quadrant tumor location, removal of only a single SLN, minimal surgeon experience, presence of a single positive axillary LN, and use of immunohistochemistry (IHC) for SLN analysis were independently associated with an increased risk of FN results. CONCLUSIONS: Surgeon experience, tumor size and location, and the number of SLN removed are preoperative and intraoperative factors that independently predict the risk of a FN result. In contrast to suggestions from other smaller studies, age does not affect the likelihood of a FN result; a lesser, rather than greater, number of positive axillary nodes was associated with an increased likelihood of a FN result; and IHC analysis of the SLN increases, rather than decreases, the risk of FN results.  相似文献   
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