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71.
A pseudotumor, giant regenerative nodule, or macroregenerative nodule is an unusual benign hepatic lesion in biliary atresia (BA) patients. This tumor may mimic malignant transformation and may preclude liver transplantation (LT). The clinical and imaging surveillance of patients after the Kasai procedure is therefore an important aspect of management of BA patients. Our objective is to report our experience and describe the incidence, imaging, and pathologic features of pseudotumors in BA patients awaiting LT. From August 1990 to December 2006, 133 LTs for BA were performed. Five (3.8%; 4 female, 1 male) patients were diagnosed with pseudotumor. The patients' records were reviewed. The diagnostic imaging modalities used were abdominal ultrasound (US), computed tomography (CT) scan, and magnetic resonance imaging (MRI). Histologic confirmation of the lesions was obtained in all cases. All underwent the Kasai operation in early infancy. Six of 7 lesions in 4 of 5 patients were demonstrated by pretransplant imaging. Two of 7 tumors were detected by US. Five of 7 lesions were detected by CT, and 5 of 7 lesions were demonstrated by MRI. In 1 patient, the lesion was not seen in the US, CT, or MRI but was found during surgery and confirmed by histology. An additional tumor was found incidentally during histologic examination in a patient previously diagnosed to have 2 tumors by CT and MRI. In another patient diagnosed to have 2 tumors on imaging, pathology revealed only a single tumor. In conclusion, although unusual, pseudotumor should be included in the differential diagnosis of liver masses in BA children.  相似文献   
72.
目的 探讨军人花粉症治疗的有效方法。方法 采用提高起始浓度和快速递增浓度 ,上臂外侧皮下注射的方法对 10 6位军人花粉症患者行快速免疫治疗 ,并对每一位患者治疗前后检测血清中总IgE和嗜酸细胞阳离子蛋白 (ECP)。 结果 治疗前后患者总IgE和ECP值有显著性差异。 10 6例患者经 1~ 3年随访复查 ,78例 2个以上发病季节未发作 ,或仅有轻微鼻痒、眼痒 ,18例症状减轻 ,发病时间缩短半月 ,10例症状无明显改善。显效 82例 ,有效 14例 ,无效 10例 ,总有效率为 90 .5 7%。结论 快速免疫治疗能使患者血清总IgE和ECP下降 ,对军人花粉症疗效好。  相似文献   
73.
Foreign bodies in the heart are a rare but serious form of cardiac injury. The objects usually are sharp pointed. Such as acupuncture needles,sewing needles, coat hangers, fragments of Kirschner wires, pins, etc. 1 We report a patient with a metallic pellet lodged in the heart, which was accurately diagnosed and successfully removed.  相似文献   
74.
目的:观察3种常用化疗药对正常大鼠血清胃泌素及D-木糖醇浓度的影响。方法:将动物随机分为4组,即对照组、ETX组、5-Fu组和THP组,检测胃泌素及D-木糖醇浓度等指标。结果:3组化疗组上述指标与对照组比较,差异有统计学意义(P〈0.05,P〈0.01)。结论:正常大鼠用ETX、5-Fu和THP,血清胃泌素及D-木糖醇浓度明显减低,从临床表现、胃肠功能方面提示3种常用化疗药可导致正常大鼠脾虚证的发生。  相似文献   
75.
OBJECTIVE: To evaluate the possibility and reliability of the hyoid-sternohyoid graft transfer in the correction of server subglottic laryngotracheal stenosis, and delineate the operation skills and clinical results. METHODS: Seven patients with severe subglottic stenosis underwent laryngotracheal reconstruction using the hyoid grafts with sternohyoid muscle flaps (HG-SHMF). Five of these patients had traumatic subglottic stenosis, one with scar tissue of unknown etiology arising in the subglottic region, another with tracheal narrowing caused by inhalation of hydrochloric acid. RESULTS: All seven patients were successfully decannulated with moderate good voice. The average time from reconstruction to decannulation was 15.4 months. The stent was endoscopically removed with a range of 3 to 22 months; the mean time required for stenting was 9.6 months. Two patients who received additional salvage reconstruction procedures because of graft or stent displacement were extubated with improved voices and satisfactory airway. CONCLUSIONS: The HG-SHMF transfer was a single-stage reconstruction, relatively simple procedure that can restore an adequate airway and a good voice. Patients undergoing laryngotracheal reconstruction with HG-SHMF must have regular, long-term follow-up since graft displacement and recurrent granulation tissue or scar reformation can cause restenosis after an initially successful surgery. This procedure should be used in a large number of patients to further test its reliability.  相似文献   
76.
A commercially available ADAC Pinnacle(3) radiation treatment planning system has been used to model electron beams from a Varian Clinac 2300C/D in the energy range of 6 to 22 MeV. Prior to clinical use, the dosimetric characteristics of the beams have to be modeled accurately. As a first step for beam modeling, a number of dose profile and depth dose measurements were taken at standard source-to-surface distance (SSD) of 100 cm. Dose profiles and depth dose measurements at extended SSDs up to 120 cm are important for ascertaining accuracy of the model, as well as their clinical usefulness in the treatment of some sites (e.g., head-and-neck tumors). Modeled and measured beam data were compared. Over 98% of comparison points (modeled vs. measured) at 100-cm SSD were within 2.5% or 2.5 mm. At 110 cm SSD, over 98% of compared points were within 4% or 4 mm, and at 120-cm SSD, over 98% of compared points were within 5% or 5 mm. Overall, more than 98% of compared points were within 4% or 4 mm. Better models were produced for lower energies (6 to 15 MeV) than higher energies (18 and 22 MeV). For 6, 9, 12, and 15 MeV, 89% of compared points were within 2% or 2 mm. For 18- and 22-MeV electron energies, 75% and 67%, respectively, were within 2% or 2 mm. These results are consistent with the recommendations of AAPM Task Group Report 53.  相似文献   
77.
Acute exposure to a neurotoxin, 3-nitropropionic acid (3-NPA), in rats results in an increase in total free fatty acid (FFA) concentration in selective brain regions. We investigated the effect of 3-NPA administration on the cerebral concentrations of FFA used as a marker of oxidative stress. Rats (n=3/group) were dosed subcutaneously (s.c.) either with a vehicle (phosphate buffer) or 3-NPA in phosphate buffer at 30 mg/kg body weight. Animals were sacrificed after 1, 2, 3, and 6 h of injection. Brains were then dissected into frontal cortex (FC), caudate nucleus (CN), and hippocampus (HIP). The concentration of total FFA increased from 130 to 300% within 1–2 h after 3-NPA injection in all brain regions when compared with the baseline level obtained from the control rats and taken as 100%. In CN, FFA returned to the baseline level within 3 h of treatment. However, in FC and HIP the concentration of FFA remained significantly elevated above the baseline until 6 h. The released FFA provide a substrate for free radicals formation. The results of this study suggest a role of oxidative stress in the mechanism of 3-NPA toxicity.  相似文献   
78.
用高速离心、分段盐析、亲和层析、超滤和阴离子交换层析法,从牛胎盘中分离纯化出一种肝细胞生长因子。结果表明,此因子的最终得率为0.005mg/g牛胎盘,其分子量约为99000u,它能强烈刺激原代培养大鼠肝细胞的DNA合成。提示利用自制的亲和层析凝胶,通过此提纯流程可以得到一种肝细胞生长因子。  相似文献   
79.
Background: The lack of depth perception and spatial orientation in video vision are the drawbacks of laparoscopic surgery. The advent of a three-dimensional camera system enables surgeons to regain binocular vision and may be advantageous in complex laparoscopic procedures. Methods: We prospectively studied two groups of surgeons (with and without experiences in laparoscopic surgery) who performed a designated standardized laparoscopic task using a two-dimensional camera system (Olympus OTV-S4) vs a three-dimensional camera system (Baxter-V. Mueller VS7700) and compared their time performances. Results: The results suggested that only experience in laparoscopic surgery had significant effect on individual's performance. We could not demonstrate any superiority of the 3D system over the 2D system. However, two-thirds of the surgeons commented that the depth perception did improve. Conclusions: With further refinement of the technology, the 3D system may improve its potential in laparoscopic surgery.  相似文献   
80.
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