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This retrospective study investigated the effects of rituximab in 19 pediatric patients (15 girls and 4 boys) with chronic refractory symptomatic immune thrombocytopenic purpura (ITP). Patients received from 2 to 5 weekly infusions of rituximab (375 mg/m(2)); 15 patients were younger than 12 years when treated. The median follow-up time was 30 months (range, 9-43 months). The overall response rate was 68% (13/19 patients). Six responders relapsed at a median of 4.5 months (range, 3-8 months). Seven patients still displayed a platelet count >150,000/microL at a median of 33 months (range, 14-43 months) after rituximab treatment. Six of 15 patients treated with 4 or 5 weekly infusions and 1 of 4 patients treated with 2 or 3 infusions are still in remission. No difference was detected between splenectomized and nonsplenectomized patients. The duration of ITP disease at the time of treatment did not influence the response rate. Patients still in remission showed significantly lower levels of CD19+ cells after 4 and 6 months than nonresponding or relapsed patients (P < .05). No major infections were reported during follow-up. Our data show the efficacy and tolerability of rituximab in young children with refractory symptomatic ITP. Nonrelapsed patients showed a more prolonged B-cell depletion.  相似文献   
73.
MR angiography of the carotid arteries: parameters affecting image quality   总被引:1,自引:0,他引:1  
RATIONALE AND OBJECTIVES: This study was performed to evaluate the relationship between dose levels of contrast medium and image quality in magnetic resonance (MR) angiography of the carotid arteries with fluoroscopically monitored, manually triggered, elliptically ordered image acquisitions. MATERIALS AND METHODS: Twenty-five patients with clinical indications for angiography of the carotid arteries were examined with MR at 1.5 T by using a fluoroscopically monitored, manually triggered, elliptically ordered pulse sequence with the administration of one of three different volumes of gadolinium-based contrast medium. The signal intensities of the vessel lumen and the surrounding tissues were measured in single partitions at the origin of the common carotid artery, the carotid bifurcation, and the intracranial internal carotid arteries. The contrast-to-noise ratio in these regions of interest also was measured. Maximum intensity projection image quality was appraised for blurring, artifacts, venous enhancement, background suppression, and contrast medium distribution. RESULTS: No artifacts or venous enhancement was observed. The position of the fluoroscopic section affected the distribution of contrast medium along the vessel, as evidenced by the difference between the contrast-to-noise ratio at the origin of the common carotid artery and the ratio at the carotid bifurcation and the intracranial internal carotid arteries (P < .01). The contrast medium dose administered was strongly correlated with image quality (r = 0.90). CONCLUSION: Contrast medium dose is related to image quality in MR angiography of the carotid arteries performed with elliptical ordering, fluoroscopic monitoring, and manual triggering.  相似文献   
74.
Background: After open or laparoscopic Roux-en-Y gastric bypass (RYGBP) for morbid obesity, the bypassed stomach and duodenum are not readily available for radiological and endoscopic evaluation. Furthermore, little is known about the long-term physiologic and histologic changes that occur in the bypassed GI segments following these procedures. Many alternative radiological and endoscopic techniques have been described to access the distal gastric pouch and the duodenum after RYGBP. Apart from percutaneous gastrografin? studies, all these techniques require the insertion of a gastrostomy tube in the distal stomach. Methods: a new diagnostic method to access the bypassed segments by virtual CT gastroscopy (VG) was used in 5 morbidly obese patients who underwent laparoscopic RYGBP (LRYGBP). Results: All patients tolerated the procedure well, which appears safe and suitable for an outpatient setting.The virtual images offered an excellent intraluminal view of the stomach and duodenum. Conclusions: VG holds promise as the method of choice in the follow-up of LRYGB patients, having the potential to detect inflammatory changes and cancer in the excluded segments early.  相似文献   
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Study ObjectiveTo investigate whether diabetes, hypertension (HTN), and obesity can be considered risk factors for endometrial polyps (EPs) independently of age and menopausal status.DesignRetrospective analysis (Canadian Task Force classification III).SettingDepartment of Obstetrics and Gynecology of the University of Foggia, Italy.PatientsA total of 353 Caucasian women undergoing office hysteroscopy to assess abnormal uterine bleeding, infertility, cervical polyps, and abnormal sonographic patterns.InterventionsDemographic characteristics and data on diabetes, HTN, and menopausal status were collected and anthropometric parameters were analyzed. Vaginoscopic hysteroscopy was performed with a 5-mm continuous-flow operative office hysteroscope. When present, EPs were treated during the same procedure by means of 5-Fr scissors or electrode.Measurements and Main ResultsIn 134 (38%) of 353 cases, EPs were found. Univariable and multivariable analysis were performed to verify the presence of a statistically significant association among age, menopause, HTN, obesity, diabetes (independent variables), and the presence of EPs. Univariable logistic analysis showed a statistically significant association among age, menopause, HTN, obesity, and the presence of EPs. However, when multivariable logistic regression was performed, all the independent variables, except age, lost statistical significance (OR 1.05, 95% CI 1.02–1.07, p <.001).ConclusionAlthough it appears that EP is a disorder of aging, the significance of diabetes, HTN, and obesity, as well as menopause, on the development of EPs should be reconsidered.  相似文献   
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Gastric carcinoma is one of the most frequent malignancies in the world and its clinical behavior especially depends on the metastatic potential of the tumor.In particular,lymphatic metastasis is one of the main predictors of tumor recurrence and survival,and current pathological staging systems reflect the concept that lymphatic spread is the most relevant prognostic factor in patients undergoing curative resection.This is compounded by the observation that two-thirds of gastric cancer in the Western world...  相似文献   
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