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91.
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
92.
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
93.
Sequential production and activation of matrix-metalloproteinase-9 (MMP-9) with breast cancer progression 总被引:10,自引:0,他引:10
Sun Young Rha Joo Hang Kim Jae Kyung Roh Kyong Sik Lee Jin Sik Min Byung Soo Kim Hyun Cheol Chung 《Breast cancer research and treatment》1997,43(2):175-181
The degradation of the basement membrane by matrix-metalloproteinase(MMP) and serine protease is a critical pointin tumor invasion and metastasis. We measured theactivity of MMP-9 from 28 normal, 12 benignand 126 breast cancer tissues using gelatin zymographywith an image analysis system. ProMMP-9 was expressedin 17.5% of the cancer patients compared to2.5% in 40 non-cancerous tissues (p=0.014).The mature form of MMP-9 (82 kD) wasexpressed only in T2–T4 stages. During the earlyphase of breast cancer (DCIS and T1 stage)progression, only production of proMMP-9 increased. However, asthe cancer grew or invaded skin (T2–T4), orwith lymphovascular permeation, both production and activation ofMMP-9 increased. In conclusion, proMMP-9 production was themain cause of increased MMP-9 activity during theearly phase, while both production and activation increasedin the late phase of breast cancer. 相似文献
94.
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
95.
Boo-Kyung Han Jung-Gi Im Hak Soo Kim Jin Mo Koo Hong Dae Kim Kyung Mo Yeon 《Korean journal of radiology》2000,1(3):127-134
Objective
To determine the extent to which thin-section and volumetric three-dimensional CT can depict airway reactivity to bronchostimulator, and to assess the effect of different airway sizes on the degree of reactivity.Materials and Methods
In eight dogs, thin-section CT scans were obtained before and after the administration of methacholine and ventolin. Cross-sectional areas of bronchi at multiple levels, as shown by axial CT, proximal airway volume as revealed by three-dimensional imaging, and peak airway pressure were measured. The significance of airway change induced by methacholine and ventolin, expressed by percentage changes in cross-sectional area, proximal airway volume, and peak airway pressure was statistically evaluated, as was correlation between the degree of airway reactivity and the area of airways.Results
Cross-sectional areas of the bronchi decreased significantly after the administration of methacholine, and scans obtained after a delay of 5 minutes showed that normalization was insufficient. Ventolin induced a significant increase in cross-sectional areas and an increase in proximal airway volume, while the effect of methacholine on the latter was the opposite. Peak airway pressure increased after the administration of methacholine, and after a 5-minute delay its level was near that of the control state. Ventolin, however, induced no significant decrease. The degree of airway reactivity did not correlate with airway size.Conclusion
Thin-section and volumetric spiral CT with three-dimensional reconstruction can demonstrate airway reactivity to bronchostimulator. The degree of reactivity did not correlate with airway size. 相似文献96.
97.
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
98.
Jung Sook Seo Kyung Mi Yang Jung Mi Kim Hyesun Min Chang Su Kim Betty J. Burri 《Nutrition Research》2004,24(12):959-968
This human study was conducted to evaluate the effect of chronic alcohol consumption on plasma concentrations of lipid and the antioxidative system in 44 Korean alcoholics and 45 age-, sex-, and nationality-matched nonalcoholic subjects. Plasma triacylglycerols and atherogenic index were higher in alcoholics than in control subjects. Plasma total cholesterol was not different among groups, but plasma high-density lipoprotein cholesterol was lower in alcoholics. There were positive correlations between ethanol consumption and plasma lipid peroxide and atherogenic index in all subjects; there were negative correlations between ethanol consumption and plasma high-density lipoprotein cholesterol in all subjects. There were no significant differences between alcoholics and control subjects in plasma concentrations of α-tocopherol, although plasma α-tocopherol/lipid tended to be lower in alcoholics. Plasma retinol was lower in alcoholics. These results suggest that chronic ethanol consumption can contribute to increased risk for vascular diseases in Korean alcoholics. 相似文献
99.
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
100.
The "High-Riding" superior pericardial recess: CT findings 总被引:3,自引:0,他引:3
Choi YW McAdams HP Jeon SC Seo HS Hahm CK 《AJR. American journal of roentgenology》2000,175(4):1025-1028
OBJECTIVE. We recently observed patients in whom the superior pericardial recess extended cephalad ("high-riding") into the right paratracheal region. In these patients, differentiation from mediastinal lymphadenopathy or mass was difficult. The purpose of this study was to assess the prevalence and CT features of the high-riding superior pericardial recess. CONCLUSION. Narrow-collimation CT with multiplanar reformations was useful for confidently diagnosing a high-riding superior pericardial recess and for distinguishing it from pathologic lesions. 相似文献