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1.
Society of Geriatric Cardiology 总被引:3,自引:0,他引:3
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Olfactory Neuroblastoma and Neuroendocrine Carcinoma of the Anterior Skull Base: Treatment Results at the M.D. Anderson Cancer Center 下载免费PDF全文
John R. Austin Hazel Cebrun Mathew M. Kershisnik Adel K. El-Naggar Adam S. Garden Franco DeMonte Lawrence E. Ginsberg Scott M. Lippman Helmuth Goepfert 《Skull base》1996,6(1):1-8
Updated information on the pathologic characterization and treatment of olfactory neurobiastoma (ON) and neuroendocrine carcinoma (NEC) diseases is presented. A series of patients with ON or NEC was evaluated and retrospectively staged using the UCLA system. The parameters evaluated were symptoms, age, sex, risk factor assessment, stage of disease, treatment, and clinical outcome. The median follow-up was 3 years (range, 18 months to 23 years). The predominant therapy (63%) for ON was combined surgery and radiotherapy. Surgery alone or in combination with ancillary treatment was used in 58% of patients with NEC. For the most receat years of the study, patients with NEC have been treated successfully with combined chemotherapy and radiotherapy. Seventy percent of the patients with ON and 75% of the patients with NEC were clinically free of disease during the defined follow-up period. Surgical therapy consisting of a craniofacial resection combined with postoperative radiotherapy has resulted in good local and long-term control of ON. Our experience indicates that combined chemoradiation is an appropriate therapeutic approach for NEC. 相似文献
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Said B Iskandar Mathew G Mathai Ryland P Byrd Thomas M Roy 《The Journal of asthma》2004,41(3):337-342
Asthma affects 5%-10% of adults in the United States. Older adults (> 65 years) with asthma have higher rates of fatal asthma than younger adults. The occurrence of a respiratory emergency, such as status asthmaticus, would seem likely to create a situation of cardiopulmonary dysfunction conducive to myocardial ischemia. However, multiple studies of fatal or near-fatal asthma have failed to incriminate myocardial infarction as a contributing factor. We report a patient without underlying coronary artery disease who sustained myocardial injury consistent with myocardial ischemia and infarction during status asthmaticus while receiving recommended treatment without intravenous sympathomimetics or theophylline. 相似文献
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New photosensitizers activated by longer wavelengths than 630 nm light used with Photofrin II are under evaluation by various groups for the treatment of malignancies. Any increase in tumour volume destroyed by these agents as compared to Photofrin II will be partly determined by tissue penetrance at the longer wavelengths. Attenuation coefficients were measured for various tissues at 630 nm and the more penetrative near infrared wavelength of 789 nm. A new model of light propagation in tissue is shown to be accurate for arbitrary ratios of absorption and scattering, by comparison with a rigorous solution to the transport equation. Absorption and transport scattering coefficients of tissues at 630 and 789 nm were obtained by fitting this model to optical attenuation measurements. In vitro tissues included bovine heart, kidney and tongue, pig liver and fat, and chicken muscle; in vivo tissues included Dunning R3327-AT and R3327-H tumours. The penetration depth was found to be 1.35-2.25 times greater at 789 than 630 nm, depending on tissue type. The greatest differences in penetration between the two wavelengths were in the highly pigmented tissues. These substantial increases in penetration in the infrared may be important in future applications of photodynamic therapy. 相似文献
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Adult zebrafish can completely regenerate their caudal fin following amputation. This complex process is initiated by the formation of an epithelial wound cap over the amputation site by 12 h post amputation (hpa). Once the cap is formed, mesenchymal cells proliferate and migrate from sites distal to the wound plane and accumulate under the epithelial cap forming the blastemal structure within 48 hpa. Blastemal cells proliferate and differentiate, replacing the amputated tissues, which are populated with angiogenic vessels and innervating nerves during the regenerative outgrowth phase which is completed around 14 days post amputation (dpa). Regenerative outgrowth does not occur in TCDD-exposed zebrafish. To identify the molecular pathways that are perturbed by TCDD exposure, male zebrafish were ip injected with 50 ng/g TCDD or vehicle and caudal fins were amputated. Regenerating fin tissue was collected at 1, 3, and 5 dpa for mRNA abundance analysis. Microarray analysis and quantitative real time PCR revealed that wound healing and regeneration alone altered the expression of nearly 900 genes by at least two-fold between 1 and 5 dpa. TCDD altered the abundance of 370 genes at least two-fold. Among these, several known aryl hydrocarbon responsive genes were identified in addition to several genes involved in extracellular matrix composition and metabolism. The profile of misexpressed genes is suggestive of impaired cellular differentiation and extracellular matrix composition potentially regulated by Sox9b. 相似文献
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The hydrolysis of phosphatidylinositol-4,5-bisphosphate (PIP2) by rat sciatic nerve cytosolic phosphoinositidase C [phosphoinositide-specific phospholipase C (PIC)] was studied at neutral pH and at ionic concentrations that approximate intracellular conditions. The principal water-soluble product formed was shown to be inositol trisphosphate by anion exchange chromatography. The maximum hydrolysis rate (2.5 nmol/min/mg protein) was achieved at less than 100 nM Ca2+. Hydrolysis was markedly increased to 15 nmol/min/mg protein by inclusion of K+ in the reaction mixture. In the presence of 200 mM K+, the optimum Ca2+ was increased to approximately 600 nM. Higher Ca2+ concentrations progressively inhibited PIP2 hydrolysis. Mg2+ also inhibited the reaction, but the presence of equimolar amounts of ATP and Mg2+ had no effect. Appreciable degradation of phosphatidylinositol-4-phosphate (PIP) also occurred in the nanomolar Ca2+ range, whereas breakdown of phosphatidylinositol (PI) required millimolar Ca2+. The presence of PIP but not PI inhibited PIP2 hydrolysis. Upon subcellular fractionation of nerve, more than 50% of recovered PIC activity was in the cytosol and about 20% was located in a myelin-enriched fraction. Using PIP2 as substrate, PIC activities in nerves from normal and streptozotocin-induced diabetic animals were not different. However, the myelin-associated enzyme from diabetic animals was more labile to freezing and thawing. 相似文献
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Santosh Isaac Poonnoose Raju P Manjooran John Mathew Pranatartiharan Ramachandran 《Journal of clinical neuroscience》2007,14(3):281-283
We report an unusual case of chronic subdural haematoma (CSH) associated with cerebrospinal fluid (CSF) rhinorrhoea emphasizing the importance of managing both conditions simultaneously. A 59- year-old man presented with watery discharge from the right nostril, of 2 months duration. MRI of the brain showed a CSH in the left fronto-parietal region with significant mass effect. There was an arachnoidocoele with a defect in the planum sphenoidale. He first underwent a burr hole evacuation of the CSH following which the CSF rhinorrhea did not subside, even with bed rest. Transnasal endoscopic closure of the CSF dural fistula was done. On the first post-operative day, he was disoriented and a CT scan showed a recollection of the subdural haematoma that required repeat evacuation. The patient was asymptomatic at discharge. To our knowledge this is the first reported case of CSF rhinorrhoea associated with CSH. Simultaneous closure of the CSF dural fistula at the time of evacuation of a coexisting CSH would be the optimal management. 相似文献