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61.
To evaluate the possibility of radionuclide gene therapy and imaging in hepatocellular carcinoma cancer, we investigated the iodine accumulation of a human hepatocellular carcinoma cell line, SK-Hep1, by transfer of human sodium iodide symporter (hNIS) gene. By targeting NIS expression in SK-Hep1, we could also investigate whether these cells concentrate 99mTc-pertechnetate and 188Re-perrhenate as well as 125I in vitro and in vivo. METHODS: The hNIS gene was transfected to human hepatocellular carcinoma SK-Hep1 cell lines using lipofectamine plus reagent. The uptake and efflux of 125I, 99mTc-pertechnetate, and 188Re-perrhenate were measured in the transfected and parental cells. Biodistribution was studied in nude mice bearing SK-Hep1 and SK-Hep1-NIS at 10 and 30 min and at 1, 2, 6, 16, and 23 h after injection of 125I, 99mTc- pertechnetate, or 188Re-perrhenate. In tumor imaging studies, the nude mice were intravenously injected with 188Re-perrhenate and imaged with a gamma-camera equipped with a pinhole collimator at 30 and 60 min after injection. The survival rate (%) was determined by the clonogenic assay after 37 MBq/10 mL (1 mCi/10 mL) 131I and 188Re-perrhenate treatment. RESULTS: SK-Hep1-NIS, stably expressing the NIS gene, accumulated 125I up 150 times higher than that of SK-Hep1. Iodine uptake of SK-Hep1-NIS is completely blocked by perchlorate. NIS gene transfection into SK-Hep1 also resulted in 112- and 87-fold increases of 99mTc-pertechnetate and 188Re-perrhenate uptake, respectively. Iodide efflux from SK-Hep1-NIS was relatively slow, with only 10% released during the initial 5 min, and 60% remained at 25 min. In the biodistribution study using SK-Hep1-NIS-xenographed mice, the tumor uptake of 125I, 188Re-perrhenate, and 99mTc-pertechnetate was 68.0 +/- 15.0, 46.2 +/- 9.1, and 59.6 +/- 16.2 %ID/g (percentage injected dose per gram) at 2 h after injection, respectively. After 188Re-perrhenate injection in SK-Hep1 and SK-Hep1-NIS-xenographed nude mice, whole-body images clearly visualized the SK-Hep1-NIS tumor, whereas the control tumor was not visualized. The survival rate (%) of SK-Hep1-NIS was markedly reduced to 46.3% +/- 10.1% and 28.9% +/- 5.2% after 37 MBq/mL (1 mCi/10 mL) 131I and 188Re-perrhenate treatment compared with the survival rates of the parental cells. These results demonstrated that SK-Hep1-NIS could be selectively killed by the induced 131I and 188Re-perrhenate accumulation through NIS gene expression. CONCLUSION: NIS-based gene therapy using beta-emitting radionuclides has the potential to be used in hepatocellular carcinoma management.  相似文献   
62.
Objectives: Congenital tracheal stenosis is a rare disease. Various methods for treatment exist but there is still much debate as to the appropriate surgical procedure. We present our surgical experiences of patch tracheoplasty and slide tracheoplasty as viable methods for the treatment of congenital tracheal stenosis. Methods: From 1994 to 2002, 13 patients were diagnosed with congenital tracheal stenosis. Eight patients (7 symptomatic and 1 asymptomatic) had their stenosis corrected, three by means of pericardial patch tracheoplasty, four by slide tracheoplasty, and one by resection and anastomosis. Concomitant operations were performed on six patients to treat congenital cardiovascular disease. Five patients showing no significant symptoms did not undergo tracheal surgery and received only cardiac procedures. A retrospective review of the hospital course, complications, and long-term results was conducted. Results: Among the patch tracheoplasty group, every patient suffered from granulation tissue formation. One patient died of respiratory acidosis and one was hospitalized due to recurrent granulation tissue, which required frequent bronchoscopy. The third patient from this group is free of all symptoms. Among the slide tracheoplasty group, one patient died of anastomosis disruption. The three remaining patients are alive and well. The one patient who received resection and anastomosis is alive without symptoms. Conclusions: Surgical repair of long-segment congenital tracheal stenosis exhibited high mortality and morbidity rates. Every patient that underwent pericardial patch tracheoplasty suffered from troublesome granulation tissue. As slide tracheoplasty provided relatively good results in the short and mid-term follow-up periods, it seems to be a preferred method for the treatment of long-segment congenital tracheal stenosis.  相似文献   
63.
OBJECTIVE: To evaluate the usefulness of the TenElectrodes, a new stimulator for inching test, in the diagnosis and localization of ulnar neuropathy at the elbow (UNE). METHODS: Sixty-two ulnar nerves in 40 control subjects and 24 ulnar nerves in 23 patients with typical symptoms and signs of UNE were studied. The inching test of ulnar motor nerve using TenElectrodes was done along 8 cm across the elbow in the extended position. RESULTS: In the inching test of the control group, the mean segmental latency difference was 0.19+/-0.08 ms. Maximal latency difference over a 1 cm segment did not exceed 0.40 ms in any of the controls but exceeded 0.5 ms or more in all clinical UNE patients. In all UNE patients, the lesion sites were identified by the inching test using TenElectrodes: the retroepicondylar groove (54.2%), the humeroulnar arcade (29.2%), and dual compression (16.6%). CONCLUSIONS: TenElectrodes is a useful stimulator for the inching test in the diagnosis of UNE. The precise localization of compression was possible in all patients with UNE and the most common site was the retroepicondylar groove.  相似文献   
64.
应用多层螺旋CT多方位重建技术诊断急性阑尾炎的价值   总被引:29,自引:0,他引:29  
目的探讨多层螺旋CT多方位重建(MPVR)诊断急性阑尾炎的价值。方法2002年2月至2003年9月临床疑诊阑尾炎收治入院手术患者39例,术前均作了常规扫描和MPVR重建2种CT检查,术后31例确诊为阑尾炎,从阑尾充血、水肿至阑尾脓肿共分5级(正常阑尾为0级)。结果对照手术病理,MPVR重建诊断急性阑尾炎准确率872%,敏感度903%,特异度75%,阳性预测值933%,阴性预测值667%。常规CT检查诊断急性阑尾炎准确度385%,敏感度387%,特异度375%,阳性预测值706%,阴性预测值136%。28例确诊急性阑尾炎的MPVR重建片所示5种主要征象及出现频率如下阑尾肿大(管腔直径>6mm)(964%),阑尾结石(267%),回盲部肥厚(367%),阑尾周围炎(714%),脓肿(107%)。结论多层螺旋CTMPVR重建技术显著提高了CT对临床症状模棱两可、临床疑诊急性阑尾炎患者的术前诊断能力,并可减少重型阑尾炎病例的发生。  相似文献   
65.
66.
山东省医学影像研究所所长连世海副研究员是解放后我国自己培养的一代科学家之一,1945年参加革命,1953年毕业于山东医学院,1958年任山东省立医院放射科主任,副主任医师。  相似文献   
67.
68.
目的调查门诊患者中焦虑症的患病率以及共病抑郁症状的发生率。方法在我院精神科门诊、心理咨询门诊以及社区卫生服务中心内科门诊就诊的1106例患者作为研究对象,并做SAS、SDS、HAMA量表评定。结果1106例患者中,符合焦虑症诊断,且HAMA≥14分者共93例,患病率为8.41%。SDS标准分≥50共病抑郁症状的共43例,占46.23%。HAMA分值、SAS分值与SDS分值有显著性正相关。结论门诊中罹患焦虑症的患者焦虑程度越高,共病抑郁的可能性就越大。  相似文献   
69.
Osteogenesis is synergistically enhanced by the combined effect of complimentary factors. This study showed that Nell-1 and BMP-2 synergistically enhanced osteogenic differentiation of myoblasts and phosphorylated the JNK MAPK pathway. The findings are important because of the osteochondral specificity of Nell-1 signaling and the potential therapeutic effects of coordinated BMP-2 and Nell-1 delivery. INTRODUCTION: BMPs play an important role in the migration and proliferation of mesenchymal cells and have a unique ability to alter the differentiation of mesenchymal cells toward chondrogenic and osteogenic lineages. Signaling upstream of Cbfa1/Runx2, BMPs effects are not limited to cells of the osteoblast lineage. Thus, additional osteoblast-specific factors that could synergize with BMP-2 would be advantageous for bone regeneration procedures. NELL-1 (NEL-like molecule-1; NEL [a protein strongly expressed in neural tissue encoding epidermal growth factor like domain]) is a novel growth factor believed to preferentially target cells committed to the osteochondral lineage. MATERIALS AND METHODS: C2C12 myoblasts were transduced with AdLacZ, AdNell-1, AdBMP-2, or AdNell-1+AdBMP-2 overexpression viruses. Effects were studied by cell morphology, alkaline phosphatase activity, osteopontin production, and MAPK signaling. Additionally, in a nude mouse model, viruses were injected into leg muscles, and new bone formation was examined after 2 and 8 wk. RESULTS: C2C12 myoblasts co-transduced with AdNell-1+AdBMP-2 showed a synergistic effect on osteogenic differentiation as detected by alkaline phosphatase activity and osteopontin production. Nell-1 stimulation on AdNell-1 + AdBMP-2 preconditioned C2C12 cells revealed significant activation of the non-BMP-2 associated c-Jun N-terminal kinase (JNK) MAPK signaling pathway, but not the p38 or extracellular signal-regulated kinase (ERK1/2) MAPK pathways. Importantly Nell-1 alone did not induce osteogenic differentiation of myoblasts. In a nude mouse model, injection of AdNell-1 alone stimulated no bone formation within muscle; however, injection of AdNell-1+AdBMP-2 stimulated a synergistic increase in bone formation compared with AdBMP-2 alone. CONCLUSIONS: These findings are important because of the confirmed osteochondral specificity of Nell-1 signaling and the potential therapeutic effects of enhanced BMP-2 action with coordinated Nell-1 delivery.  相似文献   
70.
With the introduction of more potent immunosuppressive agents, rejection has decreased in simultaneous pancreas/kidney transplant (SPK) recipients. However, as a consequence, opportunistic infections have increased. The purpose of this report is to outline the course of SPK patients who developed polyomavirus-associated nephropathy (PVAN). A retrospective review of 146 consecutive SPK recipients from January 1, 1996 to December 31, 2002 was performed. Immunosuppression, rejection and development of PVAN were reviewed. Nine patients were identified. All received induction with either OKT3 or thymoglobulin. Immunosuppression included tacrolimus/cyclosporine, MMF/azathioprine and sirolimus/prednisone. Two patients were treated for kidney rejection prior to the diagnosis of PVAN. Time to diagnosis was an average of 359.3 days post-transplantation. Immunosuppression was decreased but five ultimately lost function. However, none developed pancreatic abnormalities as demonstrated by normal glucose and amylase. Two underwent renal retransplantation after PVAN diagnosis and both have normal kidney function. PVAN was the leading cause of renal loss in SPK patients in the first 2 years after transplantation and is a serious concern for SPK recipients. The pancreas, however, is spared from evidence of infection, and no pancreatic rejection occurred when immunosuppression was decreased.  相似文献   
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