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骨巨细胞瘤的MRI诊断价值 总被引:10,自引:0,他引:10
目的探讨骨巨细胞瘤的MRI表现特点及其病理基础。资料与方法搜集经手术病理证实的12例骨巨细胞瘤患者资料,分析其MRI征象并与病理结果对照。结果T1WI上肿瘤实体表现为低、等信号,T2WI上为不均匀高信号,Gd-DTPA增强扫描呈中度到明显强化。此外,MRI还可显示肿瘤内坏死、出血、含铁血黄素沉着等。结论MRI能够提供比较全面的影像学信息,可提高对骨巨细胞瘤诊断的准确性。 相似文献
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Lithium hypochlorite (LiOCl), the pool and spa sanitizer/algicide, was evaluated for genotoxicity in a battery of studies designed to evaluate potential mutagenicity, DNA damage and chromosome aberrations. LiOCl was not mutagenic in the Ames test when tested in Salmonella typhimurium strains TA98, TA100, TA1535, TA1537, TA1538 or in the hypoxanthine-guanine phosphoribosyl transferase (HGPRT) mutation assay in Chinese hamster ovary (CHO) cells without metabolic activation. LiOCl did not induce DNA damage in the unscheduled DNA synthesis assay using rat primary hepatocytes. Effects on metaphase chromosomes were evaluated in vitro in CHO cells at 12 and 18 h exposure without S9 and at 12 and 22 h following a 2 h exposure with S9. LiOCl induced a statistically significant increase in chromosome aberrations at the high dose only at both harvest times without S9 and at the late harvest time with S9. There were significant increases in chromosome aberrations at the low dose, low-mid and high doses, but not at the high mid-dose at the early harvest time with S9. However, LiOCl did not increase chromosome aberrations when tested orally in rats at maximally tolerated doses. Bone marrow cells, collected 6, 24 and 48 h after a single oral dose of LiOCl to rats (100, 500, 1000 mg/kg in males; 50, 250, 500 mg/kg in females) showed no increase in the incidence of aberrations. In general, the weight of the evidence indicates that LiOCl is not genotoxic. 相似文献
5.
H. A. Tillmann Hein MD C. Tracy Suit MD Linda K. Douning MD Samuel P. Marynick MD J. Michael Putman MD Lily Zhang PhD Michael A.E. Ramsey MD 《Journal of clinical anesthesia》1997,9(8):617
This study retrospectively compares patients who underwent outpatient transvaginal follicle aspiration with either a propofol- or methohexital-based intravenous sedation technique. Data collected from patient charts (n = 212) over a 46-month period were analyzed to determine the effects of each sedation technique on procedure and recovery times, number of retrieved ova, as well as rates of nausea, fertilization, cleavage, pregnancy, and delivery. All patients were included in the study, regardless of age or diagnosis. procedure time was lower in the propofol group (51 t 18 min) than in the methohexital group (61 I 20 min) (p > 0.01). Patients in the methohexital group (139 2 51 min) spent more time in the recovery room than did those in the propofol group (71 ? 34 min) (p > 0.01). The nausea rates were significantly lower in the propofol group compared with the methohexital group (1.9% vs. 14.4%, respectively) (p > 0.02). Fertilization rate in the propofol group was 77.7% and was 62.9% in the methohexital group (p > 0.01). The numbers of retrieved ova and the cleavage rates were similar in both groups. The rate of pregnancy in patients sedated with propofol (46.1%) was higher than the methohexital group (26.9%) (p > 0.02). Delivery rate was 38.5% in the propofol group and 20.6% in the methohexital group (p > 0.02). In summary, propofol intravenous sedation for transvaginal follicle aspiration was associ- ated with an improved outcome. Pregnancy and delivery rates were higher while nausea, an unpleasant side effect, was sharply reduced. 相似文献
6.
R A Lubet R W Nims E Kiss R E Kouri D L Putman L M Schechtman 《Environmental mutagenesis》1986,8(4):533-542
Several of the major variable factors in the Syrian hamster embryo/simian adenovirus SA7 (SHE/SA7) viral enhancement assay were identified and the effects of these parameters on assay sensitivity were assessed. The extent of dose-dependent cytotoxicity and enhancement of SA7 transformation of primary SHE target cells by benzo(a)pyrene was examined through analysis of data obtained from 37 assays performed over a 2-year period. The variables analyzed for contribution to assay sensitivity included the number of SA7-induced transformed SHE cell foci enumerated in ten replicate dishes in the negative control condition (background focus count) (range: 26-139); the age of the SHE cell cultures at the time of exposure to benzo(a)pyrene (range: 72-144 hr postseeding); and the source of the pregnant hamsters used to prepare the primary SHE cells (Wilmington colony vs Lakeview colony, Charles River Laboratories, Inc., Wilmington, MA). The benzo(a)pyrene-induced cytotoxicity and enhancement of SA7 transformation responses were found to be independent of each of these variables, within the range of values tested. 相似文献
7.
Ricardo Pietrobon Anand Shah Paul Kuo Matthew Harker Mariana McCready Christeen Butler Henrique Martins CT Moorman Danny O Jacobs 《BMC medical informatics and decision making》2006,6(1):32-11
Background
Although regulatory compliance in academic research is enforced by law to ensure high quality and safety to participants, its implementation is frequently hindered by cost and logistical barriers. In order to decrease these barriers, we have developed a Web-based application, Duke Surgery Research Central (DSRC), to monitor and streamline the regulatory research process. 相似文献8.
Dr. Linda K. Green MD Susan Zachariah MS CT David Y. Graham MD 《Digestive diseases and sciences》1990,35(11):1421-1425
Summary Secondary neoplasms of the stomach are rare and are often clinical and diagnostic problems. Three patients with bleeding volcano-like ulcers were diagnosed by combined endoscopic salvage cytology and surgical biopsy as having metastatic submucosal lesions from hematologic spread. The combination of endoscopic appearance, clinical findings, and tissue and cytologic examination can lead to the correct diagnosis. The results from these cases support the utility of this cytologic technique in combination with biopsy in this clinical setting. 相似文献
9.
Multimodality treatment of nongalenic arteriovenous malformations in pediatric patients 总被引:8,自引:0,他引:8
Hoh BL Ogilvy CS Butler WE Loeffler JS Putman CM Chapman PH 《Neurosurgery》2000,47(2):346-57; discussion 357-8
OBJECTIVE: Previously reported series of arteriovenous malformations (AVMs) in pediatric patients have primarily used a single-modality treatment approach of either surgery, radiosurgery, or embolization, with significant treatment-related morbidity and mortality. At our institution, we have used a combined multidisciplinary team approach of all three treatment modalities, alone or in combination, to minimize complications and to maximize efficacy in the management of these lesions. METHODS: We retrospectively reviewed 40 consecutive pediatric patients with AVMs seen at our institution from 1991 to 1999. A multidisciplinary team planned the treatment for each AVM. The treatment modality consisted of the following approaches: surgery alone in 14 patients, a combination of endovascular embolization and surgery in 6 patients, radiosurgery alone in 11 patients, a combination of endovascular embolization and radiosurgery in 2 patients, and a combination of radiosurgery and surgery in 2 patients. Four patients are receiving ongoing multistaged treatment for reduction of the nidus size for eventual surgical resection or radiosurgical obliteration of large, complex lesions. In one patient, no treatment was recommended. RESULTS: The clinical outcomes for the overall series were 95.0% excellent or good (Glasgow Outcome Scale score 5 or 4), 2.5% fair (Glasgow Outcome Scale score 3), and 2.5% dead. Radiographic efficacy in the patients who have completed treatment was 92.9% complete obliteration of their AVMs and 7.1% incomplete obliteration. Of the 10 patients who had seizures, 9 are seizure-free. CONCLUSION: A combined multimodality approach of surgery, radiosurgery, and embolization in managing AVMs in pediatric patients can improve outcomes and minimize morbidity and mortality. 相似文献
10.
Early stage nasopharyngeal carcinoma: radiotherapy dose and time factors in tumor control 总被引:1,自引:0,他引:1
Chang JT; See LC; Liao CT; Chen LH; Leung WM; Chen SW; Chen WC 《Japanese journal of clinical oncology》1998,28(3):207-213
OBJECTIVE: To evaluate radiotherapy dose and length of treatment in the
control of early stage nasopharyngeal carcinoma (NPC) treated with a
combination of external radiotherapy and brachytherapy, MATERIALS &
METHODS: We reviewed the records of 133 patients with early stage
nasopharyngeal carcinoma (stage I or II, AJC/UICC staging system) who
received definitive radiotherapy in Chang Gung Memorial Hospital from 1979
to 1991. The median follow-up time was 7.1 years with a minimum of 2 years.
All patients were treated with megavoltage external radiotherapy to the
nasopharynx area (63-72 Gy) followed by high dose rate intracavitary
brachytherapy (5-16.5 Gy in one to three fractions, spaced 1-2 weeks
apart). The median total dose and time of irradiation was 75 Gy (69.8-81.4
Gy) and 11.6 weeks (7.8-20 weeks) respectively. Survival analysis was used
to examine the effect of several variables on prognosis. RESULTS: The
5-year rates were 86.4% for local control, 84.7% for disease free survival,
88.5% for actuarial survival and 84.2% for overall survival. The treatment
group (combination of time and dose of irradiation) was the most important
prognostic factor according to Cox's proportional hazard model. Patients
receiving radiation at a total dose of < or = 75 Gy completed in < 12
weeks showed the best prognosis. CONCLUSION: Treatment time and total
treatment dose are both important factors in treating early stage NPC.
Decreasing the total radiation time to < 12 weeks and not exceeding a
radiation dose of 75 Gy gave the best results.
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