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34.
Oren N Gottfried Steven Chin H Christian Davidson William T Couldwell 《Skull base》2007,17(5):317-324
The authors present a case of amyloid infiltration involving the trigeminal nerve that mimicked a malignant cavernous sinus tumor with perineural tumor infiltration. A 64-year-old man presented with trigeminal nerve numbness. Imaging revealed a plaque-like enhancing lesion along the right lateral cavernous sinus extending anteriorly into Meckel's cave and involving the proximal V2 and V3 branches of the trigeminal nerve. The patient underwent an extradural frontotemporal craniotomy with middle fossa exposure of the cavernous sinus to diagnose and treat the presumed malignant cavernous sinus tumor. A reddish mass involving the lateral dural wall of the cavernous sinus was resected. The gasserian ganglion, V2, and V3, the latter of which was biopsied, were enlarged. Permanent histopathological studies showed microscopic eosinophilic, amorphous material, which stained positive for Congo red, and an absence of neoplastic cells. The final diagnosis was amyloidoma. Thus, amyloidomas can involve the trigeminal nerve or ganglia and should be considered in the differential diagnosis of a cavernous sinus lesion mimicking a tumor. Patients may have symptomatic improvement of trigeminal neuropathy with resection of the amyloidoma outside the nerve capsule that is compressing the nerve, while resection of the lesion from within the capsule may result in permanent trigeminal nerve dysfunction. 相似文献
35.
Jon Artun Faraj Behbehani Badreia Al-Jame Heidi Kerosuo 《American journal of orthodontics and dentofacial orthopedics》2005,128(3):347-352
INTRODUCTION: Incisor trauma is a significant clinical problem in children and adolescents. The purposes of this study were to report on the prevalence and severity of incisor trauma in a large population-based sample of adolescent Kuwaiti residents in the early permanent dentition, to determine the ages of and reasons for the injuries, and to test for any effects of sex, incisor occlusion, and lip coverage on the prevalence of incisor trauma. METHODS: Presence and type of traumatic injury were scored according to the National Institute of Dental Research index in a population-based sample of 795 girls and 788 boys with a mean age of 13.24 years (SD 0.42). RESULTS: Trauma prevalence was higher (P < .001) in boys (19.3%) than in girls (9.7%), and in the maxilla (13.6%) than in the mandible (1.5%). Most (77.3 %) of the affected subjects had only 1 injured tooth, and most (83.7%) of the traumatized teeth were maxillary central incisors. A total of 90.3% of the injuries were unrepaired enamel or enamel/dentin fractures. The major reasons for the injuries were falls and blows indoors (48.4%) or outdoors (41.6%). Nearly two-thirds (63.0%) of the traumas occurred at age 10 years or later. Mean overjet (OJ) was larger (3.9 v 3.0 mm, P < .01), and lip incompetence more frequent (12.7% v 7.3%, P < .01) among the subjects with injured maxillary incisors than among those without. Logistic regression showed that the odds of maxillary incisor trauma were 2.8 times higher in subjects with OJ between 6.5 and 9.0 mm, and 3.7 times higher in subjects with OJ > or = 9.5 mm than in subjects with OJ < or = 3.5 mm. CONCLUSIONS: Multiple logistic regression showed that the risk of maxillary incisor trauma was about 2 times higher in boys than in girls, and that the risk increased by 13% for every millimeter of increase in OJ. Lip competence was not included in the model. No associations were found between occlusion and mandibular incisor trauma. 相似文献
36.
Catherine Guette Christian Legros Guewen Tournois Max Goyffon Marie-Louise Célérier 《Toxicon》2006,47(6):640-649
In order to establish a venom fingerprint and a peptide profile of the Lasiodora parahybana tarantula venom gland, we used conventional methods such as reversed phase liquid chromatography coupled to an electrospray-ionisation hybrid quadrupole time of flight mass spectrometer (LC/ESI-QqTOFMS), matrix-assisted laser desorption/ionization time-of-flight-MS (MALDI-TOFMS) and direct study of L. parahybana venom by nanospray-ionization QqTOFMS (nanoESI-QqTOFMS) and a new technology for the direct analysis of fresh tissues using MALDI-TOFMS. The analysis of the crude venom allowed the characterization of specific juvenile and adult biomarkers. In situ MALDI analysis of L. parahybana venom gland sections revealed different peptide expression levels all along the gland and non-processed peptide precursors, demonstrating the power of the method for the dynamic investigation of peptide evolution in the venom gland of spiders. 相似文献
37.
Christian Waydhas Dieter Nast-Kolb Steffen Ruchholtz 《European journal of trauma and emergency surgery》2007,33(2):170-175
Abstract
Objective: To define the diagnostic accuracy of clinical examination in patients with impaired consciousness or endotracheal intubation
to detect pelvic ring fractures and to identify those with severe bleeding.
Methods: Included in this prospective data collection with retrolective data analysis were a consecutive series of blunt trauma victims
with either a Glasgow Coma Scale ≤ 13 or tracheal intubation. Clinical examination comprised testing for stability of the
iliac wings.
Results: From 784 subjects (injury severity score 23.3 ± 17.4) 93 patients (11.9%) were found to have a pelvic ring fracture. Clinical
instability of the pelvic ring was found in 42 patients. There was only one false positive. Fifty-two fractures could not
be identified by clinical examination, including nine fractures (17%) that required surgical fracture stabilization (sensitivity
of clinical examination 44.1%). Seventeen fractures (18.3%) were associated with a blood loss larger than 20% of circulating
blood volume. Sixteen of those were identified by clinical instability of the pelvic ring (sensitivity 94.1%, specificity
97.0%, positive predictive value 38.1%, negative predictive value 99.9%).
Conclusions: Clinical examination for stability of the pelvis in this selected group of patients missed a significant number of pelvic
ring fractures including fractures that require surgical stabilization. The finding of a clinically unstable identifies most
of the patients with the pelvic ring fracture being a major source of bleeding. A stable pelvis makes pelvic ring fracture
as being the source of bleeding quite unlikely. 相似文献
38.
Cytomegalovirus induces T-cell independent apoptosis in brain during immunodeficiency. 总被引:2,自引:0,他引:2
Jon D Reuter 《Journal of clinical virology》2005,32(3):218-223
BACKGROUND: Cytomegalovirus (CMV) is the most common opportunistic viral pathogen associated with HIV/AIDS or immunosuppressive therapy. Systemic pathology may be caused either through direct virus-mediated infection or by indirect mechanisms such as 'by-stander' apoptosis. CMV infection of the central nervous system (CNS) occurs late in disease progression and understanding of pathology in the brain is fundamental for selection of appropriate therapies. OBJECTIVES: Using a model of disseminated neurotropic CMV disease, these experiments are designed to identify cellular predilection of murine CMV (MCMV) within mature brain and to determine, if CMV induces apoptosis within CNS cells. STUDY DESIGN: Adult immunodeficient (SCID) and normal BALB/c mice were infected via the tail vein with 4.5 x 10(5)pfu recombinant MCMV expressing a green fluorescent protein reporter. Animals were perfused at various time periods from 3 to 35 days post inoculation and tissues were stained for MCMV, GFAP, NEU-N, MBP, TUNEL, and caspase-3. RESULTS: CMV infection within brain was observed in multiple, independent foci affecting several different cell types, including neurons, glial cells, meninges, ependymal cells, and cerebral vessels. Cellular changes included nuclear karyopyknosis and karyorrhexis, and associated meningitis, choroiditis, encephalitis, vasculitis, and necrosis. TUNEL and caspase-3 staining of brain-demonstrated apoptosis of nearby 'by-stander' meningial, glial, and neuronal cells, but only in immunodeficient mice lacking T- and B-lymphocytes. Generally, only large CMV infection foci were associated with apoptosis of non-infected adjacent cells. CONCLUSIONS: These results indicate that MCMV may cause both direct and indirect pathology to brain and that T-cell independent apoptosis of surrounding cells of the CNS may be an important mechanism of disease in the pathogenesis of neurotropic CMV. 相似文献
39.
Introduction
Planning human resources for health (HRH) is a complex process for policy-makers and, as a result, many countries worldwide swing from surplus to shortage. In-depth case studies can help appraising the challenges encountered and the solutions implemented. This paper has two objectives: to identify the key challenges in HRH planning in Belgium and to formulate recommendations for an effective HRH planning, on the basis of the Belgian case study and lessons drawn from an international benchmarking. 相似文献40.
Diseases like rotavirus afflict both upper- and lower-income countries, but most serious illnesses and deaths occur among the latter. It is a vital public health issue that vaccines for these types of global diseases can recover research and development (R&D) costs from high-priced markets quickly so that manufacturers can offer affordable prices to lower-income nations. Cost recovery depends on how high R&D costs are, and this study attempts to replace high, unverified estimates with lower, more verifiable estimates for two new vaccines, RotaTeq (Merck) and Rotarix (GlaxoSmithKline or GSK), based on detailed searches of public information and follow-up interviews with senior informants. We also offer a new perspective on “cost of capital” as a claim for recovery from public bodies. Our estimates suggest that companies can recover all fixed costs quickly from affluent markets and thus can offer these vaccines to lower-income countries at prices they can afford. Better vaccines are a shared project between companies and public health agencies; greater transparency and consistency in reporting of R&D costs is needed so that fair prices can be established. 相似文献