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131.
目的 研究Ewing’s肉瘤细胞系 (RM 82 )X 射线外照射后肿瘤坏死因子 (TNF α)和转化生长因子 (TGF β)mRNA表达水平的变化 ,探讨X 射线诱导内源性TNF α和TGF β产生的可能性及意义。 方法 应用实时荧光RT PCR ,检测接受不同剂量X 线照射 (2Gy ,5Gy ,10Gy ,2 0Gy ,30Gy ,4 0Gy)和受照后不同时间 (1h ,3h ,6h ,12h ,2 4h ,4 8h ,72h)。TNF α和TGF βmRNA表达水平的变化。 结果 RM 82细胞TNF αmRNA表达水平较外照射前显著升高。一方面受照后TNF αmRNA表达逐渐升高 ,照射剂量达 4 0Gy时TNF αmRNA表达水平达高峰 ,为正常对照组的 10 8倍 ;另一方面 ,照射后 3h后TNF αmRNA表达逐渐升高 ,6h达高峰 ,为正常对照组的 18倍。相反 ,TGF βmRNA表达水平X 射线照射前后无显著变化。结论 Ewing’s肉瘤细胞系 (RM 82 )接受X 线照射后TNF αmRNA表达明显升高 ,且呈现时间、剂量依赖性。放射治疗可诱导Ewing’s肉瘤细胞系 (RM 82... 相似文献
132.
133.
Intracerebral clysis in a rat glioma model 总被引:4,自引:0,他引:4
Bruce JN Falavigna A Johnson JP Hall JS Birch BD Yoon JT Wu EX Fine RL Parsa AT 《Neurosurgery》2000,46(3):683-691
OBJECTIVE: Intracerebral clysis (ICC) is a new term we use to describe convection-enhanced microinfusion into the brain. This study establishes baseline parameters for preclinical, in vivo, drug investigations using ICC in a rat glioma model. METHODS: Intracranial pressure was measured, with an intraparenchymal fiber-optic catheter, in male Fischer rats 10, 15, 20, and 25 days after implantation of C6 glioma cells in the right frontal lobe (n = 80) and in control rats without tumor (n = 20), before and during ICC. A 25% albumin solution (100 microl) was infused through an intratumoral catheter at 0.5, 1.0, 2.0, 3.0, and 4.0 microl/min. Infusate distribution was assessed by infusion of fluorescein isothiocyanate-dextran (Mr 20,000), using the aforementioned parameters (n = 36). Brains were sectioned and photographed under ultraviolet light, and distribution was calculated by computer analysis (NIH Image for Macintosh). Safe effective drug distribution was demonstrated by measuring tumor sizes and apoptosis in animals treated with N,N'-bis(2-chloroethyl)-N-nitrosourea via ICC, compared with untreated controls. Magnetic resonance imaging noninvasively confirmed tumor growth before treatment. RESULTS: Intracranial pressure increased with tumor progression, from 5.5 mm Hg at baseline to 12.95 mm Hg on Day 25 after tumor cell implantation. Intracranial pressure during ICC ranged from 5 to 21 mm Hg and was correlated with increasing infusion volumes and increasing rates of infusion. No toxicity was observed, except at the higher ends of the tumor size and volume ranges. Fluorescein isothiocyanate-dextran distribution was greater with larger infusion volumes (30 microl versus 10 microl, n = 8, P < 0.05). No significant differences in distribution were observed when different infusion rates were compared while the volume was kept constant. At tolerated flow rates, the volumes of distribution were sufficient to promote adequate drug delivery to tumors. N,N'-Bis(2-chloroethyl)-N-nitrosourea treatment resulted in significant decreases in tumor size, compared with untreated controls. CONCLUSION: The C6 glioma model can be easily modified to study aspects of interstitial delivery via ICC and the application of ICC to the screening of potential antitumor agents for safety and efficacy. 相似文献
134.
To report our clinical experience on the use of oral erythromycin for the treatment of severe gastrointestinal dysmotility in preterm infants.
A case series study of seven preterm infants (six were very low birthweight) with severe intestinal dysmotility in a tertiary neonatal centre.
All responded favourably without adverse effects and tolerated full enteral feeding within 1–2 weeks of the commencement of the drug.
As prolonged total parenteral nutrition carries significant risk of complications, this therapy could be considered in selected preterm infants who fail to establish enteral feeding after an extended period, and in whom an anatomically obstructive lesion of the gastrointestinal tract has been excluded. Meanwhile, we would caution against the widespread implementation of this therapeutic approach until formal evaluation by randomized controlled trials have established the exact role of erythromycin, or its analogues, in the treatment of intestinal dysmotility in preterm infants. 相似文献
Methodology:
A case series study of seven preterm infants (six were very low birthweight) with severe intestinal dysmotility in a tertiary neonatal centre.
Results:
All responded favourably without adverse effects and tolerated full enteral feeding within 1–2 weeks of the commencement of the drug.
Conclusions:
As prolonged total parenteral nutrition carries significant risk of complications, this therapy could be considered in selected preterm infants who fail to establish enteral feeding after an extended period, and in whom an anatomically obstructive lesion of the gastrointestinal tract has been excluded. Meanwhile, we would caution against the widespread implementation of this therapeutic approach until formal evaluation by randomized controlled trials have established the exact role of erythromycin, or its analogues, in the treatment of intestinal dysmotility in preterm infants. 相似文献
135.
Robert L. Harris MD Geoffrey W. Cundiff MD James P. Theofrastous MD Haewon Yoon MD Richard C. Bump MD W.Allen Addison MD 《American journal of obstetrics and gynecology》1997,177(6):1367-1371
OBJECTIVE: Our goal was to evaluate the role of intraoperative cystoscopy during surgery for pelvic organ prolapse and urinary incontinence. STUDY DESIGN: Charts of 224 consecutive patients who had intraoperative cystoscopy performed after urogynecologic surgery were reviewed. RESULTS: Nine injuries occurred that were unsuspected before cystoscopy, for an incidence of 4%. Six ureteral ligations occurred, four after Burch cystourethropexy and two after vaginal culdoplasty. Intravesical sutures were noted after two Burch procedures, and another injury occurred with passage of fascia lata through the bladder during a pubovaginal sling procedure. Eight injuries were managed by removal and replacement of the suture or sling with only one requiring ureteroneocystotomy. When patients with injuries were compared with those without, there were no statistical differences in demographic or surgical parameters. CONCLUSIONS: The potential for damage to the lower urinary tract is significant with complex urogynecologic surgery. Because of the increased and delayed morbidity associated with unrecognized injury, intraoperative surveillance cystoscopy should be considered a part of all such procedures.(Am J Obstet Gynecol 1997;177:71) 相似文献
136.
137.
Yoon KH Ha HK Kim CG Roh BS Yun KJ Chae KM Lim JH Auh YH 《AJR. American journal of roentgenology》2000,175(4):1135-1139
OBJECTIVE. We describe the CT and pathologic features of malignant papillary neoplasms of the intrahepatic bile ducts in 15 patients. CONCLUSION. CT is a useful technique for revealing intraductal lesions, although the findings are nonspecific and variable. When intraductal masses or nodules are seen with localized dilatation of the intrahepatic bile ducts on CT scans, malignant papillary neoplasms of the intrahepatic bile ducts should be included in the differential diagnosis. 相似文献
138.
139.
Invasive middle ear cholesterol granuloma involving the basal turn of the cochlea with profound sensorineural hearing loss. 总被引:1,自引:0,他引:1
STUDY DESIGN: A retrospective surgical case review. SETTING: A tertiary-care, university teaching hospital. PATIENTS: The authors describe a unique case operated on for a middle ear cholesterol granuloma, which had invaded the cochlea and vestibule causing profound sensorineural deafness. INTERVENTIONS: Extended radical mastoidectomy and labyrinthectomy with musculofascial seal. RESULTS: Successful postoperative outcome with no recurrence seen after 2 years of follow up. CONCLUSION: To the authors' knowledge, this is the first reported case of a primary middle ear cholesterol granuloma with direct invasion into the cochlea. Such invasion of the otic capsule by cholesterol granulomas is rare and presents a diagnostic challenge to the attending otologist and radiologist. Salient points of the case history, pathogenesis, imaging studies, histopathology, and management are presented with a review of the current literature. 相似文献
140.
Myositis ossificans originating from the chest wall is extremely rare. We report a case of myositis ossificans occurring in a young woman with progressive painful swelling in the chest wall. Preoperative examination suggested a malignant neoplasm originating from soft tissue. Although rare, myositis ossificans is one of the potential causes of painful swelling in the chest wall, and can be mistaken for a malignant neoplasm. 相似文献