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41.
Suk Hee Heo Yong Yeon Jeong Sang Soo Shin Tae Woong Chung Heoung Keun Kang 《Korean journal of radiology》2007,8(2):180-183
We report an uncommon case of solitary, small hepatic angiosarcoma that was initially considered as a hemangioma. We present the imaging findings, with an emphasis on the initial and follow-up CT and MR findings, as well as report on the more suggestive findings of angiosarcoma than those of a hemangioma. 相似文献
42.
Thyroid-vitamin A interactions in chicks exposed to 3,4,3',4'-tetrachlorobiphenyl: influence of low dietary vitamin A and iodine 总被引:1,自引:0,他引:1
Poultry chicks receiving a low vitamin A semipurified diet and exposed to 3,4,3',4'-tetrachlorobiphenyl became hypothyroid in comparison with unexposed controls. Metabolic rate, total serum thyroxine, total serum triiodothyronine, and food intake decreased significantly while thyroid weight increased. Unexpectedly, growth rate was not affected on this diet. In the case of chicks receiving a low vitamin A--low iodine semipurified diet and exposed to the PCB congener, the hypothyroid response was apparently antagonized. Comparing exposed chicks with unexposed controls, metabolic rate and the proportion of free T3 (i.e., %T3 resin uptake) increased while total serum thyroxine and thyroid weight were unchanged. In addition, growth rate, food consumption, and serum retinol decreased on this diet. These results are interpreted to mean that growth rate may have been altered by circulating levels of retinol, and vitamin A insufficiency may predispose birds to the hypothyroid effects of PCBs. 相似文献
43.
44.
A case of a paraffinoma in the urinary bladder is presented. Plain radiography and intravenous urography showed a low attenuation filling defect in the urinary bladder, and CT demonstrated a lobulated fat-attenuation mass floating in the urinary bladder. 相似文献
45.
The relationship of the extrinsic blood supply to regeneration in graft reconstructed peripheral nerves 总被引:3,自引:0,他引:3
A F Cook H K Moon M P Lynn D Margolin E Z Browne 《British journal of plastic surgery》1988,41(3):298-304
Median nerves of rats were reconstructed with conventional or vascular nerve grafts. After 2, 3 and 4 weeks, Allen Video-Enhanced Contrast, Differential Interference Contrast (AVEC-DIC) microscopy revealed axonal transport in most preparations, with varying degrees of myelination. Radio-isotope tracer was measured in the nerve. Two and 4 week measurements revealed no difference between the graft types. At 3 weeks the vascular graft group exhibited transport along the entire length of the nerve in contrast to a relatively abbreviated path length in the conventional graft group. Nerve conduction velocities (NCV) were measured proximal to, within and distal to the grafts. Three week NCV showed no difference between the graft types. The 4 week NCV revealed normal values in the vascular graft group at points distal to and within the graft. Significant slowing was seen in the conventional grafts at both points. 相似文献
46.
Sonographic findings in 16 cases of Krukenberg tumor from gastric carcinoma were analyzed. The patients' ages ranged from 25 to 52 years (mean 42 years). The tumor involved both ovaries in 14 patients with asymmetrical masses in 9 of 14 cases. Ascites was noted in 15 cases. Echogenicity of the tumor varied from solid to predominantly cystic: solid in 8, mixed in 6, and predominantly cystic in 2 cases. Solid masses tended to be smaller than mixed or cystic masses. The primary gastric carcinoma had been diagnosed before emergence of the tumors in only 7 cases. The findings suggest that in relatively young patients with ovarian mass, particularly bilateral tumors, careful evaluation for gastrointestinal tract involvement should be done. 相似文献
47.
异氟醚控制性降压对颅内动脉瘤夹闭术血中S100B含量的影响 总被引:3,自引:1,他引:2
目的 测定颅内动脉瘤夹闭前后血中S1 0 0B蛋白含量 ,研究异氟醚控制性降压对脑功能的影响。方法 择期颅内动脉瘤夹闭术病人 30例 ,ASAⅠ~Ⅱ级 ,随机分为两组 :异氟醚降压组 (n=1 5 )和异氟醚非降压组 (n =1 5 )。非降压组术中吸入 1MAC异氟醚维持麻醉。降压组行异氟醚控制性降压 ,平均动脉压下降幅度 30 %~ 4 0 % ,夹闭动脉瘤后降低异氟醚吸入浓度 ,终止降压。分别于切皮前、动脉瘤夹闭后即刻、2、4h、术后第 1、2天取血测定S1 0 0B蛋白含量 ,并于术后 1周随访病人 ,记录有无术后神经系统并发症。结果 (1 )异氟醚降压后 30min平均动脉压由诱导前的 (95 2± 1 2 3)mmHg降至 (5 8 8± 5 4 )mmHg ,停止降压后 30min血压回升至 (75 1± 8 3)mmHg。降压后外周血管阻力及心肌收缩加速度下降 ,但心率及心输出量均无显著性变化 ;(2 )异氟醚降压组与非降压组间同一时间点血中S1 0 0B蛋白浓度无明显差异。降压组术后第 1天及第 2天血中S1 0 0B蛋白浓度均显著升高 (F =2 94 4 ,P =0 0 1 8)。结论 在颅内动脉瘤夹闭术中应用异氟醚控制性降压可能加重了术后脑损伤 ,不利于病人围麻醉期脑功能的保护 相似文献
48.
目的:探讨不同培养阶段骨髓基质干细胞成骨能力的变化及BMP-2对其成骨能力的影响。方法:培养兔骨髓基质干细胞,测定第3代和第18代细胞碱性磷酸酶及骨钙素活性;测定BMP-2对不同培养时间骨髓基质干细胞成骨能力的影响;测定rhBMP-2对细胞增殖的影响。结果:细胞传至第18代后,分泌的骨钙素(OC)水平及ALP活力明显降低,与第3代细胞相比,差异显著(P〈0.05)。第3代细胞在rhBMP-2的诱导下,分泌的OC水平及ALP活力在原基础上进一步升高,与对照组相比,差异显著(P〈0.05)。结第18代细胞在rhBMP-2的诱导下,分泌的OC水平及ALP活力在原基础上升高,与对照组相比,差异不显著(P〉0.05);随培养时间的延长,各组细胞数量均有所增加,rhBMP-2诱导组与对照组细胞无显著性差异(P〉0.05)。细胞的传代次数对细胞增殖无明显影响(P〉0.05)。结论:rhBMP-2对细胞增殖无影响。随着传代次数的增加,骨髓基质干细胞的成骨能力下降,rhBMP-2促进其成骨的能力亦下降。 相似文献
49.
Kyung‐Sub Moon Shin Jung Jae‐Hyuk Lee Tae‐Young Jung In‐Young Kim Soo‐Han Kim Sam‐Suk Kang 《Neuropathology》2006,26(2):141-146
We present a case of benign osteoblastoma of the occipital bone. Benign osteoblastoma is an uncommon primary bone tumor, which usually involves the vertebrae and the long bones. This tumor rarely develops in the calvaria, showing a preference for the temporal and frontal bones when it does. To the best of our knowledge, this case is only the eighth reported case of benign osteoblastoma confined to the occipital bone. A 20‐year‐old male presented with a mild tender mass lesion of the occipital area, just below the lambda. Plain X‐ray films and CT scans demonstrated an osteolytic mass surrounded by the sclerotic rim within the diploic space. MRI proved to be effective for the evaluation of the intracranial and intraosseous extensions of the tumor. However, it was very difficult to formulate a differential diagnosis against other osteoblastic tumors, or osteoid osteoma, in view of its radiological appearance. The final diagnosis was obtained by careful consideration of the histopathological characteristics of the tumor combined with its clinical and radiological features. Although generally regarded as benign, a complete resection is preferred over conventional curettage as this can guard against possible recurrence and malignant transformation. 相似文献
50.