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71.
On October 9-11, 2003, the third meeting of the White Matter Study Group of the International Society for Magnetic Resonance in Medicine was held in Venice, Italy. This article is the report of the meeting on how to use MRI in the diagnostic workup of multiple sclerosis (MS) and allied white matter disorders, and to define the nature and the extent of MS pathology in vivo. Both of these steps are central to the design of future treatment strategies aimed at limiting the functional consequences of the most disabling aspects of this disease.  相似文献   
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BACKGROUND: It is not clear if more intense surveillance is associated with improved survival after curative resection for cancer. In the context of a followup program after curative gastrectomy, recurrence and survival were investigated for patients presenting with either symptomatic or asymptomatic recurrence. STUDY DESIGN: A prospectively maintained gastric cancer database was used to identify all patients who underwent a curative (R0) gastrectomy from July 1985 to June 2000. Survival curves were generated for patients with either symptomatic or asymptomatic recurrence, and the prognostic variables associated with outcomes were identified. RESULTS: Of 1,172 patients who underwent a curative (R0) gastrectomy, 561 patients (48%) had documented recurrence and 382 patients had complete data about symptoms. Median time to recurrence was 10.8months for asymptomatic patients and 12.4months for symptomatic patients (p = NS). Median postrecurrence survival was 13.5months for asymptomatic patients and 4.8months for symptomatic patients (p < 0.01). Median disease-specific survival was 29.4months for asymptomatic patients and 21.6months for symptomatic patients (p < 0.05). Variables predictive of poor postrecurrence survival included symptomatic recurrence, advanced stage (III/IV), poor differentiation, short disease-free interval (<12months), and multiple sites of recurrence. CONCLUSIONS: Followup did not identify asymptomatic recurrence earlier than symptomatic recurrence. Patients with symptomatic recurrence have more aggressive disease with a shorter postrecurrence survival. The impact of detecting asymptomatic recurrence in the course of followup after curative gastrectomy could not be distinguished from the effects of four powerful biologic variables that also interact to govern outcomes.  相似文献   
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The management of mammary hypertrophy is a developing process. The common surgical options for reduction mammaplasty include amputation with free nipple graft as well as the bipedicled, inferior pedicle and vertical pedicle techniques. All techniques are used widely. Disadvantages of these procedures include nipple areola necrosis, insensitivity, hypopigmentation, and poor breast projection. Even with the standard modifications of the original techniques, the resultant breast and nipple may be wide and flat. The purpose of this study was to assess whether combined inferior pyramidal pedicle and superior glandular pedicle reduction mammaplasty can optimize nipple and breast projection. Attention will focus on the viability and sensation of the nipple areola complex. Nine patients with mammary hypertrophy were studied. The change in nipple position ranged from 7 to 13 cm. The amount of tissue removed from each breast ranged from 500 to 1150 g. Nipple/areola sensation was retained in all cases with the exception of one breast. Nipple/areola necrosis or hypopigmentation were not observed. Optimal central breast projection was maintained in all patients, and postoperative evaluation was carried out at 12 and 22 months. The patient satisfaction was very high.  相似文献   
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Mitral annular calcification and liquefaction necrosis of this lesion mimicking intracardiac tumor because of secondary hyperparathyriodism have been described in adult patients with chronic renal failure, but have not been reported in children. Chronic renal failure is one of the predisposing factors of this condition. We report the case of a 13-year-old patient with continuous ambulatory peritoneal dialysis with severe hyperparathyroidism who was found to have intracardiac and rib lesions considered to be brown tumors.  相似文献   
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The use of copper intrauterine contraceptive devices is currently limited to 2–3 years, mainly due to wire fragmentation, which was observed as early as after 8 months of use. In the resulting search for a long-lasting device, two new systems of duplex wire, with gold and platinum cores electrolytically coated with copper, were devised and studied. Initially, duplex wires and controls were exposed to physiological solution. Copper dissolution rate, and corrosion morphology were studied by weight-loss measurements and optical metallography. Similar systems were then surgically implanted in rat uteri for varying periods up to 26 weeks. Electron microanalysis of corrosion products in addition to weight-loss measurements and metallography was performed.The results showed that a uniform and ductile copper coating is obtainable by electroplating on gold and platinum wires. The rate of copper dissolution is similar to that of solid copper wire. No dissolution of gold and platinum in the controls or coated wires was detected by weight loss, metallography or atomic absorption measurements.Microanalysis of the deposits and corrosion products on the wires in the uterine environment showed the presence of compounds containing sulphur, chlorine, calcium and copper.The results of this study suggest that supplementing IUDs with copper-coated gold or platinum wires may result in significant prolongation of the life-span of the device by preventing uncontrolled loss of copper caused by wire fragmentation.  相似文献   
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Dilated perivascular spaces: hallmarks of mild traumatic brain injury   总被引:2,自引:0,他引:2  
BACKGROUND AND PURPOSE: Recent animal and human studies have shown an increased frequency of enlarged, high-convexity Virchow-Robin spaces (VRS) in several neurologic diseases, suggesting their role as neuroradiologic markers of inflammatory changes. The aim of this study was to determine the prevalence of high-convexity dilated VRS in mild traumatic brain injury (TBI). METHODS: T2-weighted, T1-weighted, fluid-attenuated inversion recovery, and T2*-weighted gradient-echo brain MR images were acquired in 24 patients with TBI (10 women, 14 men; mean age, 33.6; range, 18.1-50.8 years) and 17 age- and sex-matched healthy control subjects (nine women, eight men; mean age, 32.8; range, 18.4-47.8 years). The mean interval after TBI was 3.6 days (range, 1-9 days) in 15 patients and 3.7 years (range, 0.6-13.4 years) in nine patients. Axial T2-weighted images were used to identify dilated VRS and to measure CSF volume; T1-weighted images were used to measure brain volume. Dilated VRS were identified as punctuate areas with CSF-like signal intensity in the high-convexity white matter. RESULTS: Mean (+/- standard deviation) number of VRS was significantly higher in patients (7.1 +/- 4.6) than in controls (3.0 +/- 3.0, P = 0.002) [corrected] In controls, VRS were associated with age (R = 0.69, P < .001) whereas in patients, they neither correlated with brain and CSF volumes nor with age and the elapsed time from injury. CONCLUSION: Our results suggest that the increased number of dilated VRS is a radiologic marker of mild head injury that is readily detectable on T2-weighted images. Because their number does not vary with time from injury, VRS probably reflect early and permanent brain changes.  相似文献   
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