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Intraosseous lipomas are among the most uncommon bone tumors. They arise most often in the appendicular skeleton. There are very few reported cases of intraosseous lipomas within the skull bones. We report a case of intraosseous lipoma of the frontal bone with conventional radiography and CT findings.  相似文献   
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The involvement of glutamate mediated neurotoxicity in the pathogenesis of Alzheimer's disease is finding increasingly more acceptance in the scientific community. Central to this hypothesis is the assumption that in particular glutamate receptors of the N-methyl-D-aspartate (NMDA) type are overactivated in a tonic rather than a phasic manner. Such continuous mild activation leads under chronic conditions to neuronal damage. Moreover, one should consider that impairment of plasticity (learning) may result not only from neuronal damage per se but also from continuous activation of NMDA receptors. To investigate this possibility we tested whether overactivation of NMDA receptors using either non-toxic doses/concentrations of a direct NMDA agonist or through an indirect approach--decrease in magnesium concentration--produces deficits in plasticity. In fact NMDA both in vivo (passive avoidance test) and in vitro (LTP in CA1 region) impaired learning and synaptic plasticity. Under these conditions memantine which is an uncompetitive NMDA receptor antagonist with features of "improved magnesium" (voltage dependence, affinity) attenuated the deficit. The more direct proof that memantine can act as a surrogate for magnesium was obtained in LTP experiments under low magnesium conditions. In this case as well, impaired LTP was restored in the presence of therapeutically relevant concentrations of memantine (1 microM). In vivo, doses leading to similar brain/serum levels produce neuroprotection in animal models relevant for neurodegeneration in Alzheimer's disease such as neurotoxicity produced by inflammation in the NBM or beta-amyloid injection to the hippocampus. Hence, we postulate that if in Alzheimer's disease overactivation of NMDA receptors occurs indeed, memantine would be expected to improve both symptoms (cognition) and slow down disease progression because it takes over the physiological function of magnesium.  相似文献   
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The authors present two cases of necrotizing fasciitis (NF), one case of dermatomyositis and one case of posttraumatic muscle injury, which have similar magnetic resonance imaging findings in terms of skin, subcutaneous fat, superficial and deep fasciae and muscle involvement. These cases highlight the need for cautious interpretation of magnetic resonance imaging (MRI) findings, for they are nonspecific and the preoperative decision should be based mostly on the evolution of the clinical status.  相似文献   
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BackgroundFamilial adenomatous polyposis (OMIM #175100) and MUTYH-associated polyposis (OMIM #608456) are rare cancer-prone disorders characterized by hundreds of adenomatous polyps in the colon and rectum, which have a high probability of malignant transformation. Attenuated familial adenomatous polyposis is a variant of familial adenomatous polyposis, which is a term used for the condition in which patients have less than 100 colorectal polyps. Germline heterozygous Adenomatous polyposis coli (APC) and biallelic MUTYH (mutY DNA glycosylase) pathogenic variations are responsible for familial adenomatous polyposis and MUTYH-associated polyposis respectively. The aim of this study is to discuss the clinical manifestations of patients having pathogenic APC and MUTYH variations.MethodsWe included 27 probands who have more than 10 colonic polyps in this study. After evaluation of their clinical and family histories, the probands were screened for APC and MUTYH variations via next generation sequencing. The family members of the probands carrying pathogenic variations were screened via Sanger sequencing. ResultsAmong 27 probands, pathogenic APC and MUTYH variations were detected in 3 and 6 probands respectively. In the APC gene, 3 novel truncating variations (p.Leu360*, p.Leu1489Phefs*23, and p.Leu912*) were detected in 3 unrelated probands. In the MUTYH gene, only 2 distinct pathogenic variations were detected (p.Pro295Leu and p.Glu480del) in the homozygous or compound heterozygous state.ConclusionIn this study, molecular etiology was clarified in 9 familial polyposis patients. The p.Pro295Leu and p.Glu480del variations seem to be common in the Turkish population and may be considered as a first-step genetic test in Turkish familial polyposis patients showing autosomal recessive inheritance. However more studies are needed to reveal the exact frequency of these variations.  相似文献   
46.
Introduction: Chronic progressiveexternal ophthalmoplegia is characterisedby limitation of ocular motility in alldirections of gaze and ptosis.Innervational or myogenic factors wereclaimed to be responsible for thismotility disorder. The aim of thisstudy was toinvestigate the extraocular muscles inCPEO with computerized tomography in an attemptto distinguish extraocular musclemorphology caused by this disorderfrom that occurring in normal individuals.Methods: Eighteen orbits from 9patients diagnosed with CPEOwere included in the study. Axialand coronal scans were obtained for CTevaluation of extraocular muscles and thedimensions of extraocular muscles were measured.The control group consisted of40 orbits belonging to 20 individuals and,the results were compared with a student'st test.Results: The thickness (the verticaldimension of vertical recti and thehorizontal dimension of horizontal recti)of all rectus muscles wassignificantly decreased in comparison with the controlgroup, whereas the width (the horizontal dimensionof vertical recti and the verticaldimension of horizontal recti) was similar inboth the diseased and normal orbits.In all the rectus musclesof the diseased orbits,the normal fusiform shape was lost and the muscles appeared asthin bands.Discussion: The differentiation ofCPEO from other myogenic and neurogenicdisorders may present difficulty,and a cluster of criteria are required fora final diagnosis. CT has provento be a valuable tool in assessing extraocularmuscles [1, 2]. In this study, an extremeatrophy of all rectus muscles wasdemonstrated by means of CT. This diagnostic method mayconsequently contribute to a properdiagnosis of CPEO.  相似文献   
47.
Acupuncture, a method of traditional Chinese medicine that uses Back-Shu and Huatuo-Jiaji points, is especially effective for treating diseases of the visceral organs. Applying acupuncture on Back-Shu points affects visceral organs in many ways. For example, it dilates the bronchus, affects the heartbeat, stomach motility, urinary bladder contractions and so on. Acupuncture's effects can be explained as viscero-cutaneous, cutaneo-visceral, cutaneo-muscular, and viscero-muscular reflexes. Segmental dispersion of the sympathetic and parasympathetic systems is related to the location of Back-Shu points. Changes in visceral organs caused by application of acupuncture can be explained as modulation of the sympathetic and parasympathetic systems.  相似文献   
48.
Purpose: To investigate the effect of the cumulative exposure to estradiol (E2) during the follicular phase on IVF outcome. Methods: Patients were stimulated with recombinant FSH after GnRH agonist suppression and had a day 3-embryo transfer. Estrogen exposure was determined as the area under the curve (AUC) for serum E2 levels measured from the first day of stimulation through the day after hCG administration. Results: E2 AUC thresholds for 10th and 90th percentiles were 4704 pg/ml and 16338 pg/ml, respectively. The pregnancy and implantation rates were highest in the 10th–90th percentile group, and were statistically higher in this group than in the >90th percentile group (54.6% vs. 33.3% and 24.8% and 12.9%, respectively, for pregnancy and implantation rates, P < 0.05). Recovered mature oocytes, fertilization, and number and mean score of transferred embryos were similar. Conclusions: High cumulative E2 exposure during the follicular phase of IVF cycles has detrimental effects on implantation.  相似文献   
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