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Results of an examination of 39 patients are described and critically assessed. An analysis of the resolving power of the method of ultrasonic angiography in pathological formations of major vessels of the neck is given.  相似文献   
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OBJECTIVES: The aim was to assess the natural course of oral lichen lesions (OLL) among unselected, non-consulting individuals. SUBJECTS AND METHODS: A cohort of 327 subjects with OLL, confirmed in 1973-1974 during a population-based survey in two Swedish municipalities, was followed through January 2002 via record linkages with nationwide and essentially complete registers. A sample of 80 drawn from the 194 surviving subjects who still resided in the area in 1993-1995 was invited for interview and oral re-examination. RESULTS: At the end of follow-up, one case of oral cancer was detected, while 0.4 were expected. The overall mortality among subjects with OLL was not significantly different from that in the 15,817 OLL-free subjects who participated in the initial population based survey in 1973-1974. The lesion had disappeared in 14 (39%) of 36 re-examined subjects with white OLLs in 1973-1974, and four (11%) had transformed into red types. In the corresponding group of 19 with red forms initially, five (26%) had become lesion free and four (21%) had switched to white types. Although the cohort size does not permit firm conclusions regarding oral cancer risk, the natural course over up to 30 years appears to be benign in the great majority.  相似文献   
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PurposeTo analyze the electroclinical features, aetiology and outcome in patients with normal neurological examination and psychomotor development who presented seizures during a mild gastroenteritis (MG).Patients and methodsEvaluation of the clinical charts of 22 patients who were assessed in the Neurology Department, Hospital Nacional de Pediatría Prof. Dr. JP Garrahan between 1999 and 2007.ResultsTwelve patients were boys and 10 were girls, the age of onset ranged from 5 to 26 months, and the median age was 10 months. Rotavirus antigen test in stool was positive in 9 of 18 studied patients. The seizures were brief, focal with secondary generalization in 15 patients (68.5%), apparently generalized in 5 (22.5%) and focal in two (9%). Seven of the patients (35%) had more than one seizure in 24 h. The interictal EEG was normal in all patients. Neuroradiological studies were performed in 19 patients with a normal result. No patient was put on long-term treatment with antiepileptic drugs. Four patients had subsequent mild gastroenteritis and two of them presented convulsions during the disease. After between 12 and 67 months of follow-up, all patients had normal psychomotor development and neurological examination.ConclusionsIn this study we confirmed the association of benign infantile seizures (BIS) and MG with or without rotavirus. The identification of this entity allows avoiding unnecessary complementary studies and treatment with antiepileptic drugs.  相似文献   
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FDA’S Perspectives on Cardiovascular Devices   总被引:1,自引:0,他引:1  
The Food and Drug Administration (FDA) decision process for approving or clearing medical devices is often determined by a review of robust clinical data and extensive preclinical testing of the device. The mission statement for the Center for Devices and Radiological Health (CDRH) is to review the information provided by manufacturers so that it can promote and protect the health of the public by ensuring the safety and effectiveness of medical devices deemed appropriate for human use (Food, Drug & Cosmetic Act, §903(b)(1, 2(C)), December 31, 2004; accessed December 17, 2008 ). For high-risk devices, such as ventricular assist devices (VADs), mechanical heart valves, stents, cardiac resynchronization therapy (CRT) devices, pacemakers, and defibrillators, the determination is based on FDA’s review of extensive preclinical bench and animal testing followed by use of the device in a clinical trial in humans. These clinical trials allow the manufacturer to evaluate a device in the intended use population. FDA reviews the data from the clinical trial to determine if the device performed as predicted and the clinical benefits outweigh the risks. This article reviews the regulatory framework for different marketing applications related to cardiovascular devices and describes the process of obtaining approval to study a cardiovascular device in a U.S. clinical trial.  相似文献   
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Prior findings led us to hypothesize that West Nile virus (WNV) preferentially transports along motor axons instead of sensory axons. WNV is known to undergo axonal transport in cell culture and in infected hamsters to infect motor neurons in the spinal cord. To investigate this hypothesis, WNV was injected directly into the left sciatic nerve of hamsters. WNV envelope-staining in these hamsters was only observed in motor neurons of the ipsilateral ventral horn of the spinal cord, but not in the dorsal root ganglion (DRG). To evaluate the consequence of motor neuron infection by WNV, the authors inoculated wheat germ agglutinin—horseradish peroxidase (WGA-HRP) 9 days after WNV sciatic nerve injection, and stained the spinal cord and the DRG for HRP activity 3 days later. The degree of HRP-staining in DRG was the same in WNV- and sham-infected animals, but the HRP-staining in the motor neuron in the ventral horn was considerably less for WNV-infected hamsters. To investigate the mechanism of WNV transport, hamsters were treated with colchicine, an inhibitor of membranous microtubule-mediated transport. The intensity of the WNV-stained area in the spinal cord of colchicine-treated hamsters at 6 days after WNV infection were significantly reduced (P≤.05) compared to the placebo-treated hamsters. These data suggest that WNV is preferentially transported through the motor axons, but not the sensory axons, to subsequently infect motor neurons and cause motor weakness and paralysis.  相似文献   
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