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61.
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SB Grover N Midha M Gupta U Sharma VH Talib 《Journal of Medical Imaging and Radiation Oncology》2005,49(2):175-178
The clinical manifestations of chronic disseminated histoplasmosis are non-specific and resemble those of other chronic infections and malignancies. We report the radiographic, sonographic and contrast-enhanced CT appearances of histoplasmosis in an adult male with non-insulin dependent diabetes mellitus, who was HIV negative and presented with weight loss and pyrexia. Imaging studies simulated tuberculosis with mediastinal lymphadenopathy, bilateral fibrotic lung lesions, hepatomegaly and bilateral hypoattenuating adrenal enlargement, without clinical or laboratory evidence of hypoadrenalism. Computed tomography-guided fine-needle aspiration biopsy of adrenal glands revealed Histoplasma capsulatum. We report our experience to increase awareness of the imaging spectrum of disseminated histoplasmosis and its similarity to tuberculosis as, with increasing incidence of AIDS, the chances of these infections are likely to increase. Moreover, awareness of this entity is important because it is known that untreated disseminated histoplasmosis is fatal. 相似文献
64.
Needle biopsy of renal allografts: comparison of two techniques 总被引:2,自引:0,他引:2
Bogan ML; Kopecky KK; Kraft JL; Holladay AO; Filo RS; Leapman SB; Thomalla JV 《Radiology》1990,174(1):273-275
Two techniques for renal allograft biopsy were retrospectively evaluated to compare relative safety and efficacy. After ultrasound (US) localization of the kidney and biopsy with a hand-held 14-gauge cutting needle, an adequate specimen was obtained in 74 of 77 cases (96%). Major complications occurred in six of these 77 cases (8%). One hundred four biopsies were performed by using a smaller 18-gauge cutting needle with a spring-loaded biopsy "gun" and real-time US guidance. With this newer technique, specimens adequate for diagnosis were obtained in 99 biopsies (95%). There was a single major complication with this technique (1%). The 18-gauge needle with real-time US guidance yields comparably adequate specimens with a lower frequency of complications. 相似文献
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66.
Inaccuracies associated with the automated measurement of mean cell hemoglobin concentration in dehydrated cells 总被引:1,自引:0,他引:1
Because of discrepancies between electronically and manually measured values of mean cell hemoglobin concentration (MCHC) encountered in studies of pathologic red cells, we studied the effect of cell water content on MCHC measurements by both methods. A series of red cell samples with varying water contents (54%-164% normal) were prepared from normal cells using the antibiotic nystatin. MCHC was then measured, using the microhematocrit centrifuge and three different electronic cell counters in common laboratory use. For MCHC values above 36 g/dl as measured by the spun hematocrit method, all three electronic counters under estimmated the MCHC, with increasing error as the true MCHC increased. For MCHC values below 30 g/dl, the values from two conductivity based instruments agreed with those from the spun hematocrit method, whereas one instrument based on light scattering overestimated the MCHC. These results indicate that inaccuracies in the measured mean cell volume (MCV) of dehydrated or otherwise undeformable cells may lead to spurious values for MCHC when electronic cell counters are used. 相似文献
67.
人脂肪干细胞复合脱细胞软骨基质支架在生物反应器中构建组织工程软骨 总被引:5,自引:5,他引:5
目的:观察人脂肪干细胞复合脱细胞软骨基质支架在生物反应器中初步构建组织工程软骨的可行性。方法:实验于2005-04/2006-05在解放军总医院骨科研究所完成。脂肪组织和关节软骨均来自膝关节置换术中切除的组织,并经患者知情同意。关节软骨冻干后经粉碎机粉碎,过筛,选取25~38μm大小的软骨微粒。在样品中先加入2.5g/L胰蛋白酶,37℃消化24h,再加入1%Triton X-100震荡72h。将软骨微粒和蒸馏水按1∶3的比例混合后滴加在模板中,置入冷冻干燥机冻干后行紫外线交联。紫外线照射8h完成。最后经25kGy 60Co辐照灭菌完成支架制备。取膝关节置换术中切除的髌下脂肪垫,酶消法获得脂肪干细胞,扩增后复合于脱细胞软骨基质制成圆柱状三维支架上(细胞密度5×1010L-1),置于生物反应器中进行诱导培养,同时设静态培养组作为对照,3周后观测大体形态和组织学形态变化,同时进行组织化学(包括番红花O,阿利新蓝染色)和Ⅱ型胶原免疫组织化学分析。结果:生物反应器组诱导培养3周苏木精-伊红染色显示支架结构消失,只有中心区域残存少量支架结构;静态培养组支架结构尚存在,有少量基质分泌。番红花O染色显示生物反应器组细胞外有大量蛋白聚糖沉积,阿利新蓝染色表明有软骨特异性蛋白多糖的聚集;而静态培养组只有部分区域染色且淡于生物反应器组。Ⅰ型胶原免疫组化的结果显示,在生物反应器组细胞能够合成大量软骨细胞特异性胶原成分,而静态培养组呈弱阳性。结论:生物反应器培养明显促进了脂肪干细胞的增殖与软骨分化,是体外构建组织工程软骨的良好方法。 相似文献
68.
Background
Nasopharyngeal carcinoma (NPC) is a type of neoplasm that is highly prevalent in East Asia and Africa with Epstein-Barr virus (EBV), genetic, and dietary factors implicated as possible aetiologic factors. Previous studies suggested the association of certain cytokines with the invasion and metastatic properties of NPC. The present study examined the roles of EBV latent membrane protein-1 (LMP1), interleukin-6 (IL-6), interleukin-10 (IL-10), transforming growth factor-beta 1 (TGF-β1) and laminin in the regulation of matrix-metalloproteinases (MMPs) and vascular endothelial growth factor (VEGF) in NPC. The effects of these factors on bmi-1, an oncogene, and ngx6, a tumour suppressor gene, were also investigated. 相似文献69.
Paulsson AK McMullen KP Peiffer AM Hinson WH Kearns WT Johnson AJ Lesser GJ Ellis TL Tatter SB Debinski W Shaw EG Chan MD 《中国神经肿瘤杂志》2013,(1):52-52
PURPOSE: We investigate the patterns of failure in the treatment of glioblastoma(GBM) based on clinical target volume(CTV) margin size,dose delivered to the site of initial failure,and the use of temozolomide and intensity-modulated radiotherapy(IMRT).METHODS: Between August 2000 and May 2010,161 patients with GBM were treated with radiotherapy with or without concurrent temozolomide.Patients were treated with CTV expansions that ranged from 5 to 20 mm using a shrinking field technique.Patterns of failure and time to progression and overall survival were compared based on CTV margin,use of temozolomide,and use of IMRT.Kaplan Meier analysis was used to estimate survival times,and χ test was used for comparison of cohorts.RESULTS: For patients treated with 5-,10-,and 15-to 20-mm CTV,79%,77%,and 86% experienced failures in the 60 Gy volume,respectively.Forty-eight percent,55%,and 66% of patients with 5-,10-,and 15-to 20-mm CTV experienced failures in the 46 Gy volume,respectively.There was no statistical difference between patients treated with 5-,10-,15-to 20-mm margins with regard to 60 Gy failure(P=0.76),46 Gy failure(P=0.51),or marginal failure(P=0.73).Eighty percent of patients receiving temozolomide experienced failures in the 60 Gy volume.There was no increased likelihood of marginal failures in patients receiving IMRT(P =0.97).CONCLUSIONS: Modern treatment techniques including use of concurrent temozolmide,limited CTV margin size,and IMRT have not greatly changed the patterns of failure of GBM. 相似文献