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11.
目的 探讨骨显像在诊断儿童常见恶性实体瘤骨转移中的价值。方法 202例恶性实体瘤(淋巴瘤91例、神经母细胞瘤81例、横纹肌肉瘤20例、肾母细胞瘤10例)患儿行^99Tc^m-MDP全身骨显像,观察各自骨转移发生率、表现特征及好发部位。结果 202例患儿骨显像阳性者92例,占45.5%,其中单发病灶20例,多发病灶72例。好发部位为下肢骨骼和椎体。91例淋巴瘤骨显像阳性者38例,占41.8%,单发与多发性转移灶分别占28.9%与71.1%。肾脏受累15例,占16.5%;81例神经母细胞瘤阳性46例,占56.8%,单发与多发性转移灶分别占21,7%与78.3%。原发灶显影30例,占37.0%;20例横纹肌肉瘤阳性8例,占40,0%;10例肾母细胞瘤均未见骨骼转移。结论 骨显像对诊断儿童恶性实体瘤的骨转移有一定的价值,神经母细胞瘤的骨转移最常见,肾母细胞瘤极少发生骨骼浸润。^99Tc^m-MDP骨显像可显示恶性淋巴瘤的肾脏受累情况。  相似文献   
12.
The value of the Technetium-99m tin colloid (TTC) scan in thediagnosis of renal transplant rejection occurring more than1 month following transplantation was assessed. To our knowledge,use of this agent has not previously been reported. Gamma cameraimaging was performed on 15 occasions in 14 patients in whomplasma creatinine was rising and in three patients in whom renalfunction was stable. Both a qualitative and a quantitative assessmentof images was made. The radioactivity recorded over the graft at 12–16 mmpost injection was expressed as a percentage of that recordedat 0–4 min. In the nine patients in whom graft perfusionwas adequate to allow interpretation of the TTC scan and inwhom rejection was diagnosed by biopsy (six cases) or on clinicalgrounds (three cases), the index ranged from 45 to 153%. Intwo patients the graft was poorly perfused and the accumulationof TTC was predictably low despite the presence of rejection.In the seven patients with either a stable creatinine or withrising creatinine not due to rejection, the index ranged from5 to 43%. Previously reported studies have shown that sulphur colloidsmay be of value in diagnosing graft rejection. This study suggeststhat Tc99m tin colloid may be regarded as a suitable alternativescanning agent and that some simplification of data collectionand analysis can be achieved.  相似文献   
13.
对134Cs诱发体细胞和生殖细胞的畸变效应进行了比较研究。方法观察内污染不同放射性活度134Cs时诱发同体骨髓细胞和精原细胞染色体畸变的量效关系,以及同一放射性活度134Cs作用不同时间诱发上述两种细胞的染色体畸变产额。结果研究发现,134Cs内照射诱发的骨髓细胞染色体畸变产额显著高于精原细胞,而其诱发的染色体畸变类型均以染色单体型畸变为主。结论由不同放射性活度134Cs所诱发的染色体畸变产额而言,骨髓细胞要比精原细胞高出1.5~5倍。  相似文献   
14.
In contrast to conventional film angiography, the perfusion pattern of hepatic arterial chemotherapy was consistently visualized by DSA in 40 patients with implanted Infusaid pump or Port-A devices. Incomplete perfusion of a liver region by the cytotoxic agent was recognized by DSA as accurately as by nuclide scintigraphy. Furthermore, DSA appeared to be more sensitive in determining aberrantly perfused extrahepatic regions; this was especially true when there was a nonligated right hepatic artery. Specific details of vascular lesions and associated complicating events also could be satisfactorily analyzed by DSA only.  相似文献   
15.
对100例骨转移瘤进行了分析,阳性率63.7%,以胸部受累最多。讨论了其它方法报告不同的原因是检查时机、灵敏度、范围和方法不同所致。核素骨显像灵敏度高,检查范围大,是早期寻找骨转移、划分病期、引导病理活检和判断疗效的理想方法。随着(153)钐的应用,给骨转移瘤的治疗开辟了一个新途径。确认核素骨显像对转移性骨肿瘤的早期诊断和治疗均有较大的临床价值。  相似文献   
16.
Forty-nine patients were treated with either 3×75 MBq 89Sr or saline as placebo. Analysis of results 1 to 3 years after therapy revealed the ineffectiveness of 89Sr to relieve pain from metastases. Unexpectedly, a higher survival rate was found after Sr application (46% vs 4% after 2 years). Covariate analysis underlines the effect of 89Sr therapy on life expectation.  相似文献   
17.
We report a case of massive cerebrospinal fluid (CSF) leakage where the tracer injected intra-thecally for radionuclide cisternography was later visualized in the bowel as well as the nasopharynx. We discuss the potential implications of this finding in patients with CSF leaks. A brief review of the diagnosis of CSF leaks is included.  相似文献   
18.
It is generally accepted that the lung uptake of 67Ga in patients with pneumocystis carinii pneumonia (PCP) is diffuse and bilateral. Three cases of focal lung uptake of 67Ga in AIDS patients with PCP but without other opportunistic infection are described. While focal lung uptake is characteristic of opportunistic infections other than PCP, we wish to emphasize that focal uptake of gallium in the chest does not rule out PCP and may represent its earliest stage of presentation.  相似文献   
19.
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目的 探讨辅助检查在诊断亚急性甲状腺炎中的作用。方法 回顾分析372例亚急性甲状腺炎病人所做的各项辅助检查结果。结果 血沉,B超,彩色多普勒,甲状腺核素扫描,甲状腺吸^131I率测定,细针穿刺细胞学,TMA,TGA等项检查诊断本病的阳性率分别为93.75%,81.63%,95.62%,89.66%,69.70%,89.41%,13.46%和9.62%。T3,T4,TSH检查结果随着病程的进展变化较大。结论 血沉检查对诊断本病缺乏特异性;彩色多普勒,细针穿刺细胞学检查诊断率高,特异性强,是首选的检查手段;甲状腺核素扫描可以准确地反映甲状腺功能状态;检测血清中T3,T4,TSH水平可以协助诊断本病,判断疾病所处时期。  相似文献   
20.
Objectives It is known that, in fluorine-18 fluorodeoxyglucose Positron Emission Tomography (FDG PET) for the diagnosis of oral cancer, FDG uptake may vary even among different cases of the same squamous cell carcinoma. However, the details of this phenomenon have not yet been elucidated. In this study, we analyzed the relationship between histopathological findings in oral squamous cell cancer and PET findings on FDG uptake. Methods We examined 45 patients with oral squamous cell carcinoma who had undergone FDG PET before treatment. FDG uptake was assessed by a standardized uptake value (SUV) calculated according to the PET-measured tissue concentration of FDG, the administered dose of radionuclide, and the body weight of the patient. The relationship between the mean SUV and each of the following parameters was examined: histological grade of malignancy, degree of cell differentiation, size and/or local extent of the primary lesion, and cell density of the tumor. Results The mean SUV of FDG uptake did not depend on the histological grade of malignancy or on the degree of cell differentiation, but tended to be greater the larger the primary lesion. SUV also depended on cell density, increasing with the percentage of tumor parenchyma. Conclusions It is concluded that cancer cell density greatly influences the SUV of FDG, in that a tumor with fewer cellular elements in cancer tissue tends to become a false negative.  相似文献   
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