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排序方式: 共有551条查询结果,搜索用时 15 毫秒
101.
目的:评价肾上腺外伤性血肿的CT检查的意义。方法:回顾分析了经临床随访证实6例肾上腺外伤性血肿的CT资料。结果:6例肾上腺外伤性血肿均发生于右侧,6例在外伤10d内行CT检查。CT平扫:表现为卵圆形、梭形块影。病灶最大径4.5 cm×2.0 cm,其中,高密度4例、等密度1例、低密度1例。CT值在24~62 Hu之间。增强扫描:病灶不强化,2例在血肿边缘可见强化的肾上腺,其外周可见等密度条索影;4例合并少量腹水;2例合并肝撕裂伤。结论:CT可以早期明确肾上腺外伤性血肿的诊断。对于腹部闭合性损伤患者应早期行CT检查,必要的增强扫描,对于肯定和/或排除肾上腺血肿的诊断有重要价值。 相似文献
102.
目的探讨硫酸锌对高脂喂养载脂蛋白E(ApoE)基因敲除小鼠血脂和氧化低密度脂蛋白(oxLDL)水平,及主动脉中基质金属蛋白酶9(MMP-9)和细胞分化抗原40(CD40)mRNA表达的影响。方法 AopE基因敲除小鼠连续14周喂饲高脂饲料,同时分别给予小鼠浓度为2.5、25 mmol/L硫酸锌水溶液作为低剂量组和高剂量组。测定小鼠血脂和oxLDL水平,并测定主动脉中MMP-9和CD40 mRNA表达水平。结果低剂量组和高剂量组小鼠血清中甘油三酯和oxLDL水平明显低于动脉粥样硬化(AS)模型组(P〈0.01)。低剂量组和高剂量组小鼠主动脉MMP-9 mRNA和CD40 mRNA水平与AS模型组没有差异。结论补充硫酸锌降低了AS模型动物的甘油三酯和oxLDL水平,具有潜在的抗AS作用,但对主动脉MMP-9和CD40 mRNA表达无影响。 相似文献
103.
目的为斜坡区肿瘤手术提供解剖资料。方法20例整颅,10例行水平切面,10例行正中矢状切面。测量切牙孔、前鼻棘、后鼻棘、枕骨大孔前端、枕髁前端、卵圆孔、破裂孔、颈动脉管外口及舌下神经管外口的内侧缘至咽结节的距离;测量卵圆孔、破裂孔、颈动脉管外口及舌下神经管外口的内侧缘至正中线的距离;测量枕骨基底部颅底外面的长径、枕骨大孔纵径(FML)、枕骨大孔前正中点与枕髁后缘连线垂直距离(AOCP)、枕髁轴径(OCA)、枕髁间距。结果切牙孔后缘、前鼻棘、后鼻棘、枕骨大孔前端、枕髁前端、卵圆孔、破裂孔、颈动脉管外口及舌下神经管外口的内侧缘至咽结节的距离分别为(mm):72.12±4.25、77.77±3.89、33.73±2.07、13.14±1.91、15.71±1.74、27.51±2.12、15.98±1.98、25.93±2.23、19.15±1.49。卵圆孔、破裂孔、颈动脉管及舌下神经管外口的内侧缘至中线的距离分别为:25.55±1.63、11.72±1.70、25.75±1.98、17.41±1.41。枕骨基底部颅底外面长径、FML、AOCP、OCA、枕髁间距分别为(mm):28.80±2.67、35.84±2.59、17.10±1.13、24.55±2.35、21.07±1.92。结论经口咽至斜坡区的手术入路中,开骨窗时安全范围是以咽结节为中心,以15mm为半径做斜坡磨除;也可以做矩形骨窗,即以咽结节为中心开一长(高)25mm×宽20mm的骨窗。 相似文献
104.
目的:研究低氧时小鼠肺组织中低氧诱导因子-1α(HIF-k)表达的变化。方法:实验用雄性小鼠,低氧仓浓度分别为10%、7%、5%。用免疫荧光组织化学技术及共聚焦显微术,检测小鼠在低氧条件下肺组织中HIF-1α表达的变化。结果:正常组小鼠肺组织HIF-1α无表达,低氧组HIF-1α表达增加,且随低氧时间的延长及低氧强度的增加而增强。结论:低氧可诱导小鼠肺组织中HIF-1α的表达增强,(HIF-k)可能参与肺组织细胞凋亡的发生。 相似文献
105.
Percutaneous angioplasty in clinical management of renovascular hypertension: initial and long-term results 总被引:1,自引:0,他引:1
Martin LG; Price RB; Casarella WJ; Sones PJ; Wells JO Jr; Zellmer RA; Chuang VP; Silbiger ML Jr; Berkman WA 《Radiology》1985,155(3):629-633
Between January 1980 and July 1983, percutaneous transluminal angioplasty was attempted on 137 stenotic renal arteries in 100 patients. At termination of follow-up studies (3-39 months, mean of 16 months), 70% of those treated for hypertension had benefited from the procedure. Stenosis secondary to fibromuscular dysplasia responded better than stenosis from arteriosclerosis (85% and 65% of the patients, respectively). Benefit was minimal for those with stenosis of the renal artery ostium or renal insufficiency. Determining levels of renal vein renin before angioplasty is helpful in selecting patients; following angioplasty, this has considerable significance in predicting the success of the procedure. 相似文献
106.
Thirty-three patients with a variety of disorders of the thoracic aorta (aneurysm, dissection, Marfan syndrome, coarctation/pseudocoarctation, L-transposition, and Takayasu disease) were evaluated with magnetic resonance (MR) imaging. MR imaging delineated the presence and extent of thoracic aortic aneurysms and showed the relationship of the aneurysm to arch vessels; it also demonstrated intimal flaps and individual lumina in types A and B aortic dissection. Dilation of the ascending aorta in Marfan syndrome and focal narrowing of the aorta in coarctation were well visualized. The anteroposterior and side-to-side relationships of the aorta and pulmonary artery in L-transposition were demonstrated, as were aortic wall thickening and branch vessel narrowing in Takayasu arteritis. Initial experience suggests that MR imaging may provide a noninvasive method for evaluating thoracic aortic disease. Limitations include inferior spatial resolution, occasional difficulty in imaging the entire region of interest in one section, lack of signal from calcifications, and inability to monitor critically ill patients. 相似文献
107.
Ocular and orbital lesions: surface coil MR imaging 总被引:1,自引:0,他引:1
Bilaniuk LT; Schenck JF; Zimmerman RA; Hart HR Jr; Foster TH; Edelstein WA; Goldberg HI; Grossman RI 《Radiology》1985,156(3):669-674
Nine lesions, four ocular (three melanomas, one hemangioma) and five orbital (two perioptic meningiomas, one hemangioma, one pseudotumor, one mucocele), were evaluated by magnetic resonance surface coil imaging at 1.5 T. Small ocular lesions with 3.9-4.5-mm-elevation were demonstrated. The use of two different pulse sequences resulted in separation of melanoma from adjacent retinal detachment. Contrast obtained between orbital lesions and the adjacent normal structures was better than that demonstrated with high-resolution computed tomography. 相似文献
108.
109.
110.
Transfusion-associated graft-versus-host disease: risk due to homozygous HLA haplotypes 总被引:11,自引:0,他引:11
BACKGROUND: Transfusion-associated graft-versus-host disease (TA-GVHD) may occur in transfusions of blood from HLA-homozygous persons to HLA- heterozygous persons who share a haplotype. STUDY DESIGN AND METHODS: Two mathematical models were developed to calculate the upper and lower limit of the associated risks in various populations using a combination of serology- and DNA sequence-based HLA haplotype frequencies. RESULTS: For nondirected transfusion, the range of the estimated risk in United States whites is 1 of 17,700 to 39,000 (1/6,900-48,500 in Germans; 1/1,600-7,900 in Japanese). The risk in directed donation between parents and children is increased at least 21- fold for US whites, 18-fold for Germans, and 11-fold for Japanese. CONCLUSION: For nondirected transfusions, the estimates of TA-GVHD risk derived in this model are lower than estimates of previously published models, are in better agreement with the clinical experience, and explain in part the observed discrepancy between TA-GVHD incidence in the United States and that in Japan. Most notably for US whites, the relative increase in risk in directed transfusion is larger than previously thought. 相似文献