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101.
Jaundice develops in many patients with liver metastases from colorectal adenocarcinoma during hepatic arterial infusion chemotherapy (HAIC). The usual cause is thought to be hepatotoxicity from the chemotherapeutic agent or biliary obstruction from progressive neoplastic disease. The authors evaluated the abdominal computed tomography and ultrasound examinations performed on 49 patients who were jaundiced during long-term HAIC. In only one patient was diffuse intrahepatic biliary dilatation caused by an obstructing mass in the porta. Two patients had metastatic hepatic lesions causing focal biliary obstruction. Intrahepatic dilatation without an obstructing mass occurred in 20 patients. Percutaneous or endoscopic cholangiograms were commonly interpreted prospectively as showing extrinsic compression by metastases, but no mass was confirmed on imaging studies. Seven patients had focal intrahepatic ductal dilatation from stricture without an associated mass. The remaining 19 patients had normal-caliber ducts; their jaundice was caused by chemical hepatitis. This series suggests that the most common causes of jaundice in these patients are chemical hepatitis and common bile duct stricture, complications of intraarterial chemotherapy, rather than neoplastic obstruction. Stricture formation may be confused with extrinsic compression on direct cholangiograms. 相似文献
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Di Chiro G; Girton ME; Frank JA; Dietz MJ; Gansow OA; Wright DC; Dwyer AJ 《Radiology》1986,160(1):221-222
Canine cerebrospinal fluid rhinorrhea, which occurs frequently in purebred beagles, was demonstrated in two dogs on magnetic resonance images after cisternal introduction of gadolinium-DTPA dimeglumine. 相似文献
104.
The ability of diagnostic intravenous digital subtraction angiography (IVDSA) to demonstrate the degree of renal artery stenosis was compared with that of intraarterial angiography in 45 patients with 92 arteries. Stenotic lesions on both IVDSA and intraarterial studies were classified as normal (0% stenosis), minor (less than 50%), low grade (50%-80%), and high grade (80%-99%). There was agreement about the degree of stenosis in 90% of the cases. IVDSA grading was correct in 94% of atheromatous lesions and in 56% of the fibromuscular dysplastic lesions. In the high-grade atheromatous lesions, the degree of stenosis was slightly overestimated on IVDSA studies in 22.5% of the cases. In fibromuscular dysplasia, stenosis was underestimated in 33% of the cases. 相似文献
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107.
H-2 effects on cell-cell interactions in the response to single non-H-2 alloantigens. II. H-2 D region control of H-7.1-specific stimulator function in mixed lymphocyte culture and susceptibility to lysis by H-7.1- specific cytotoxic cells 下载免费PDF全文
The relative immunogenicity of the H-7.1 alloantigen has been shown in a previous communication to be regulated by a gene in the D region of the mouse major histocompatibility (H-2) complex. The level of relative immunogenicity was inferred from survival times of H-7.1-incompatible skin grafts donated by donors with different H-2 haplotype origins of H-2D region genes. In this communication we report the results of an extension of these previous investigations into the possible role of H-2D region genes in controlling the capacity of H-7.1-incompatible lymphocytes to stimulate H-7.1-speciflc mixed lymphocyte culture proliferation and generation of cytotoxic effector cells. The results reported herein demonstrate that the H-2D genotype of H-7.1-incompatible stimulator cells determines the relative H-7.1-specific capacity of those lymphocytes to stimulate H-7.1-specific proliferation of in vivo primed responder T cells in secondary mixed lymphocyte culture. H-2D(b)-bearing, H-7.l-incompatible stimulators were significantly more effective in stimulating H-7.1-specific proliferation than H-2D(d)-bearing stimulators. As expected, H-2D(b), H-7.1-in-compatible stimulators were also more effective than H-2D(d) a stimulators in generating H-7.1- specific cytotoxic effector cells. Further, the susceptibility of (51)Cr- labeled, H-7.1-incompatible lymphoblast targets to H-7.1-specific lysis was similarly regulated by an H-2D gene. Reciprocal H-2 restriction (F(1) cells are capable of killing only the cells bearing the immunizing cell parental H-2 haplotype) observed by other investigators for cytolysis of non-H-2-incompatible targets was not observed. H-2D a-bearing, H-7.1- incompatible stimulators stimulated generation of cytotoxic effectors capable of detectably lysing H-2D(b) but not H-2D(a)-bearing, H-7.1- incompatible targets. The impact of these observations on the proposed models for H-2 restriction of non-H-2 histocompatibility antigen-specific cytolysis is discussed. 相似文献
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109.
个性化颅骨成形术中植入材料类型与颅骨缺损面积的关系 总被引:2,自引:0,他引:2
目的:分析个性化颅骨成形术中,植入材料类型与颅骨缺损面积的关系。
方法:选择解放军总医院第二附属医院神经外科2002-03/2005-01和河北省三河市医院神经外科2003-09/2005-04收治的资料齐全的计算机辅助设计颅骨成形术患者75例,分为嵌入性材料(骨水泥、硅橡胶)组40例,根据颅骨缺损面积又分为大面积(≥36cm2)组17例和小面积(〈36cm2)组23例;覆盖性材料(钛网)组35例,大面积组14例和小面积组21例。采用头颅CT超薄扫描(层厚1.5mm),三维重建,模拟缺损颅骨补片,应用激光快速成形技术,制作缺损颅骨及颅骨补片模型,患者认可后,根据患者的病情应用硅橡胶、骨水泥、钛网作为植入材料,进行手术植入。术后1周观察并发症:头痛、积液、松动。
结果:75例患者的补片与颅骨完整适配,塑形满意,术中无需修整,平均手术时间45min,83%(63/75)患者感到基本或完全恢复了原有容貌。手术并发症:嵌入性材料组头痛4例,积液10例,松动2例,共16例,其中大面积组13例,小面积组3例;覆盖性材料组头痛1例,积液2例,松动0例,共3例次,其中大面积组2例,小面积组1例。应用精确概率分析,两材料组之间手术并发症差异显著,两材料组颅骨缺损面积之间手术并发症差异显著,嵌入性材料大面积组与覆盖性材料大面积组之间手术并发症差异显著,嵌入性材料小面积组与覆盖性材料小面积组之间手术并发症无显著性差异。
结论:个性化设计的颅骨修补材料,能够最大限度的恢复患者外形,缩短手术时间,大面积的颅骨缺损应用钛网修补,小面积的应用钛网和嵌入性材料修补。根据患者颅骨缺损面积,选择不同植入材料,可以提高手术疗效,减少术后并发症。 相似文献
110.
Transfusion-associated graft-versus-host disease (TA-GVHD) may occur whenever immunologically competent allogeneic lymphocytes are transfused to an immunocompromised recipient. Irradiation of blood components eliminates the risk of TA-GVHD but may damage the cellular elements in the transfused component, particularly if the cells are stored for prolonged periods in the irradiated state. To study the effect of irradiation on long-term storage of red cells, AS-1 red cells from eight normal subjects were prepared on two occasions. On one occasion, the units were stored as standard AS-1 red cells for 42 days at 4 degrees C; on the other, they were exposed to 3000 cGy radiation within 4 hours of collection and then were stored as AS-1 red cells for 42 days at 4 degrees C. The donations were at least 12 weeks apart. Irradiated units demonstrated significant elevations in poststorage plasma hemoglobin (Hb) (623 +/- 206 vs. 429 +/- 194 g/dL [6230 +/- 2060 vs. 4290 +/- 1940 g/L], p less than 0.02) and plasma potassium (78 +/- 4 vs. 43 +/- 9 mEq/L [78 +/- 4 vs. 43 +/- 9 mmol/L], p less than 0.01) and significant decreases in red cell ATP (1.9 +/- 0.2 vs. 2.1 +/- 0.3 microM/g Hb, p less than 0.04) and 24-hour posttransfusion red cell recovery (68.5 vs. 78.4%, p less than 0.02), as compared to nonirradiated units. It can be concluded that irradiation with 3000 cGy damages red cells and that long-term storage in the irradiated state may enhance this damage. Red cells should not be stored for 42 days after irradiation with 3000 cGy. 相似文献