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Neuroimaging in Pineal Tumors   总被引:4,自引:0,他引:4  
F Reis  MD  AV Faria  MD  PhD  VA Zanardi  MD  PhD  JR Menezes  MD  F Cendes  MD  PhD  LS Queiroz  MD  PhD 《Journal of neuroimaging》2006,16(1):52-58
BACKGROUND AND PURPOSE: The authors report radiological findings in 11 tumors in the pineal region, which were histologically diagnosed as germinomas, pineocytomas pineoblastomas, ependymomas, teratomas, and astrocytomas. METHODS: Computed tomography (CT) was performed in seven patients and magnetic resonance imaging (MRI) was performed in all patients. RESULTS: CT showed a solid or solid/cystic mass with variable contrast enhancement. MRI showed a heterogeneous mass, with hypointense signal on T1 and iso/hyperintense signal on T2-weighted images (WI) and gadolinium enhancement. Extension to adjacent structures occurred in five patients and spread through the cerebral spinal fluid (CSF) in two. CONCLUSIONS: Pineal region tumors have no pathognomonic imaging pattern. MRI and CT are complementary in diagnosis and are important to determine localization, extension, and meningeal spread.  相似文献   
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Public concern surrounding antibiotic contamination in food and food products has made it imperative to develop analytical methods for their detection. Polyclonal antibodies were used in the development of a surface plasmon resonance (SPR)-based inhibition immunoassay for cephalexin. A conjugate consisting of cephalexin-bovine serum albumin (BSA) was immobilized on the dextran gel surface of the sensor chip. Binding/regeneration studies of antibody to immobilized cephalexin were studied and dissociation of the antibody from the immobilized cephalexin was easily achieved with 10 mmol l-1 NaOH. Forty surface regeneration cycles were carried out and found to be reproducible with only a 7.4% decrease in binding over this number of regenerations. Model inhibition immunoassays for cephalexin were developed in PBS and spiked milk samples with detection ranges of 4.88 to 2,500 ng ml-1 and 244 to 3,906 pg ml-1, respectively.  相似文献   
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Myo-inositol transport in the central nervous system   总被引:18,自引:0,他引:18  
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Summary.  In July 1997 a lyssavirus was isolated in Denmark from a colony of Egyptian flying foxes (Rousettus aegyptiacus) originating from a Dutch zoo. Sequencing of a 400 nucleotides coding region of the nucleoprotein and of a major part of the G-protein ectodomain encoding region of the newly isolated virus, revealed a very high similarity with European Bat Lyssavirus subtype 1a (EBL-1a). For characterisation of the recently isolated lyssavirus in frugivorous zoo bats, 16 frugivorous bats (Rousettus aegyptiacus) of the same colony and 80 mice were experimentally infected with the Rousettus isolate or with a well defined EBL-1a strain isolated from a Dutch insectivorous bat (Eptesicus serotinus). Inoculation viruses were titrated in mice to determine LD50‘s of both isolates. Clinical signs of inoculated bats were recorded during 6 weeks. After showing neurological signs or at the end of the experimental infection all animals were euthanized. During the experimental infection sera and various tissues of inoculated bats were collected. Immunoassays, mouse inoculation tests (MIT) and polymerase chain reaction (PCR) were employed for detection of lyssavirus specific antibodies, antigen or RNA. Five bats inoculated with the Rousettus isolate and 2 bats inoculated with the Eptesicus isolate showed neurological signs. The remaining 9 bats survived and cleared the virus; at least under the detection limit of the used assays. Despite a much higher pathogenicity of the Rousettus isolate observed in mice, LD25’s in bats were quite the same for the 2 isolates. The pathogenicity of both isolates suggested that like many other mammals, Rousettus aegyptiacus bats could be victims of lyssavirus infection besides reservoir hosts of infectious EBL1a. There was no significant difference in detecting the different lyssavirus isolates in Rousettus aegyptiacus bats. An employed immunoperoxidase staining (IP) method was very useful for sensitive detection and localization of lyssavirus antigen in histologic preparates. Received July 26, 1999/Accepted February 18, 2000  相似文献   
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This multicentre, double-blind, randomised trial in 109 patients compared the efficacy and tolerance of the novel selective serotonin and noradrenaline reuptake inhibitor (SNRI) antidepressant milnacipran (50 mg twice daily, n=53) with the established tricyclic agent imipramine (75 mg twice daily, n=56) over a period of 6 weeks, in patients with major depression (Montgomery-Asberg depression rating score (MADRS) > or =25). Initiation of antidepressant medication was conducted during a 2-week period of hospitalisation, after a 3- to 7-day washout period. Concomitant psychiatric medication was limited to lorazepam, cyamemazine, chloral hydrate and long-term uncomplicated lithium therapy. Assessment for efficacy using the MADRS and Hamilton rating scales of depression, a visual analogue scale and global evaluation revealed both agents to be highly effective (P=0.0001) in this group of patients. Milnacipran was found to be of similar efficacy to imipramine. Tolerance, assessed by physiological and biochemical examinations with routine inventory and spontaneous report of adverse events, revealed a clear advantage for milnacipran. The incidence of anticholinergic events with milnacipran was about half that with imipramine and the overall incidence of adverse events by either reporting method was markedly lower with milnacipran than with imipramine. Furthermore, the patient drop-out rate with imipramine was double that experienced with milnacipran. Milnacipran appears to possess equal antidepressant efficacy to imipramine but with markedly superior tolerance. Therefore, milnacipran constitutes an important new treatment option in major depression.  相似文献   
9.
About 15% of the Dutch population has, in a more or lesser degree, complaints about bad breath. This is caused particularly by the anaerobic metabolism of a number of oral microorganisms, in which putrefaction occurs and volatile sulfur compounds will be formed. Some of these compounds are also possibly involved in the pathogenesis of periodontitis. A good oral hygiene is of primary importance to prevent halitosis and to reduce bad breath. Antiseptic mouth-waters can be helpful in the reduction of the bacterial metabolism. In addition, stimulation of the salivary secretion has a dual favourable effect, firstly because of its antimicrobial salivary proteins, and secondly by reduction of the retention of nutrients in the oral cavity.  相似文献   
10.
The clinical use of glass-ionomer increases, also for restorative goals. The longevity of glass ionomer restorations is among others determined by premature contact with saliva and by acid erosion. The adherence to the dental hard tissues may be increased by acid pretreatment. The longevity data presented here indicate that glass ionomer restorations do not last as long as amalgam restorations. In the deciduous teeth the material seems to be a more acceptable substitute for amalgam. The same holds true for restorations which are not submitted to stress, such as class V.  相似文献   
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