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11.
Neurofibrillary tangles are described in Guamanian and post-encephalitic forms of motor neuron discase (MND) but not in sporadic MND. We report the neuropathological findings in a 79-year-old man who died after a 1-year history of MND without extrapyramidal features or dementia. There was no family history of neurological disease and he had not visited Guam. The spinal cord showed loss of anterior horn cells, and skeletal muscle typical changes of denervation. The brain appeared macroscopically normal but histology revealed many neurofibrillary tangles, particularly in medial temporal lobe structures, insula, nucleus basalis, hippocampus, oculomotor nucleus, raphe nuclei and locus ceruleus. Neurofibrillary tangles were not seen in the primary motor cortex, which appeared histologically unremarkable. Occasional tangles were present in the substantia nigra and pontine nuclei. None were seen in the cerebellum, medulla or spinal cord. The tangles were argyrophilic, and, in sections stained with thioflavin-S, both the intracellular and the extracellular tangles fluoresced strongly under ultraviolet light. The intracellular neurofibrillary tangles reacted strongly with an antibody to tau protein, and only occasional tangles showed weak ubiquitin immunoreactivity. Scattered neuropil threads were present in the cortex in the areas of neurofibrillary tangle formation. No plaques were present in any part of the brain and no A4/ protein immunoreactivity was detected. Ultrastructural examination revealed Alzheimer-type neurofibrillary tangles composed of paired helical filaments. The present findings further extend the spectrum of diverse neurological disorders associated with neurofibrillary tangles. 相似文献
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Harley B Messinger Egilius LH Spierings Arnaud JP Vincent John Lebbink 《Cephalalgia : an international journal of headache》1991,11(1):13-18
In two headache questionnaire surveys we inquired about the occurrence of headache in the mothers, fathers, siblings and children of the respondents. In total, 633 people completed valid questionnaires, 260 in the first survey and 373 in the second. The hypothesis was that familial headache occurrence would be positively associated with headache frequency. In each survey, the regression of headache frequency on the number of parents having headache was highly significant. Neither sex nor the sibling and children variables were significant predictors. In the cross-tabulations of the parental occurrence of headache with headache frequency we saw a clear "break-point" between the "no headache" and the headache frequency categories studied. For the final analyses the dichotomy "headache/no headache" was related in fourfold tables to headache occurrence in the father and the mother separately, and to the number of headache parents. The positive associations were not simply due to the large number of migraine cases since they remained after removing the migraineurs. 相似文献
14.
Early stage nasopharyngeal carcinoma: radiotherapy dose and time factors in tumor control 总被引:1,自引:0,他引:1
Chang JT; See LC; Liao CT; Chen LH; Leung WM; Chen SW; Chen WC 《Japanese journal of clinical oncology》1998,28(3):207-213
OBJECTIVE: To evaluate radiotherapy dose and length of treatment in the
control of early stage nasopharyngeal carcinoma (NPC) treated with a
combination of external radiotherapy and brachytherapy, MATERIALS &
METHODS: We reviewed the records of 133 patients with early stage
nasopharyngeal carcinoma (stage I or II, AJC/UICC staging system) who
received definitive radiotherapy in Chang Gung Memorial Hospital from 1979
to 1991. The median follow-up time was 7.1 years with a minimum of 2 years.
All patients were treated with megavoltage external radiotherapy to the
nasopharynx area (63-72 Gy) followed by high dose rate intracavitary
brachytherapy (5-16.5 Gy in one to three fractions, spaced 1-2 weeks
apart). The median total dose and time of irradiation was 75 Gy (69.8-81.4
Gy) and 11.6 weeks (7.8-20 weeks) respectively. Survival analysis was used
to examine the effect of several variables on prognosis. RESULTS: The
5-year rates were 86.4% for local control, 84.7% for disease free survival,
88.5% for actuarial survival and 84.2% for overall survival. The treatment
group (combination of time and dose of irradiation) was the most important
prognostic factor according to Cox's proportional hazard model. Patients
receiving radiation at a total dose of < or = 75 Gy completed in < 12
weeks showed the best prognosis. CONCLUSION: Treatment time and total
treatment dose are both important factors in treating early stage NPC.
Decreasing the total radiation time to < 12 weeks and not exceeding a
radiation dose of 75 Gy gave the best results.
相似文献
15.
Holladay JT Piers PA Koranyi G van der Mooren M Norrby NE 《Journal of refractive surgery (Thorofare, N.J. : 1995)》2002,18(6):683-691
PURPOSE: The aim of this study was to design and evaluate in the laboratory a new intraocular lens (IOL) intended to provide superior ocular optical quality by reducing spherical aberration. METHODS: Corneal topography measurements were performed on 71 cataract patients using an Orbscan I. The measured corneal surface shapes were used to determine the wavefront aberration of each cornea. A model cornea was then designed to reproduce the measured average spherical aberration. This model cornea was used to design IOLs having a fixed amount of negative spherical aberration that partially compensates for the average positive spherical aberration of the cornea. Theoretical and physical eye models were used to assess the expected improvement in optical quality of an eye implanted with this lens. RESULTS: Measurements of optical quality provided evidence that if this modified prolate IOL was centered within 0.4 mm and tilted less than 7 degrees, it would exceed the optical performance of a conventional spherical IOL. This improvement occurred without an apparent loss in depth of focus. CONCLUSION: A new IOL with a prolate anterior surface, designed to partially compensate for the average spherical aberration of the cornea, is intended to improve the ocular optical quality of pseudophakic patients. 相似文献
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Blackett PR Blevins KS Quintana E Stoddart M Wang W Alaupovic P Lee ET 《Metabolism: clinical and experimental》2005,54(2):180-187
Because Native Americans are predisposed to obesity and type 2 diabetes associated with coronary artery disease, we assessed whether apoC-III bound to apoB-containing (LpB:C-III) and apoA-containing (LpA:C-III) lipoproteins, total apoC-III, apoB, and plasma lipids are associated with insulin resistance, body mass index (BMI), and waist circumference in Cherokee children and adolescents aged 5 to 19 years (n = 975). A cross-sectional analysis was done to determine associations of the lipoproteins with the homeostasis index (HOMA-IR) and BMI. When the data were grouped by quartiles for HOMA-IR and separated by three 5-year age groups (5-9, 10-14, and 15-19 years), the trend for LpB:C-III, triglyceride, and BMI z score to increase was significant for all age groups and both genders (P < .001). The trend to increase LpB:C-III with age was greater in boys (P < .0001) than in girls (P < .05) who tended to plateau after the age of 10 years. In contrast, the ratio of LpA:C-III to LpB:C-III decreased and the decrease was greater in boys (P < .0001) than girls (P < .01). Body mass index z score and waist circumference were correlated with LpB:C-III, triglyceride, apoB, and non-high-density lipoprotein cholesterol within each gender (P < .001). In multiple regression models, LpB:C-III, the dependent variable, was associated with HOMA-IR for both genders. We conclude that increases in LpB:C-III in childhood and adolescence are associated with insulin resistance and obesity supporting the need for prevention programs. 相似文献
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Daubeney PE Delany DJ Anderson RH Sandor GG Slavik Z Keeton BR Webber SA;United Kingdom Ireland Collaborative Study of Pulmonary Atresia with Intact Ventricular Septum 《Journal of the American College of Cardiology》2002,39(10):1670-1679
OBJECTIVES: We describe the morphologic variability in pulmonary atresia with intact ventricular septum (PAIVS) within a population-based study. BACKGROUND: An uncommon disease, PAIVS shows considerable morphologic heterogeneity. Clinical reports, based mostly on small samples of patients, may not reflect the true spectrum of pathology of this condition. We have studied the entire range of morphology in a prospective population-based study of patients over a five-year period (1991 to 1995). METHODS; As part of the United Kingdom and Ireland Collaborative Study of PAIVS, all 18 pediatric cardiac centers were visited by a single investigator. Morphologic features of each case were determined by direct review of the echocardiograms and angiocardiograms, from surgical and autopsy reports, and by review of pathology specimens where available. RESULTS: Among 183 live-born infants, atresia was valvar (membranous) in 74.7% and muscular in 25.3%. Muscular obliteration of the apical trabecular cavity, and in some cases its infundibulum, resulted in "bipartite" right ventricle (RV) in 33.6%, and a "unipartite" chamber in 7.7%. The remaining 58.7% had "tripartite" morphology. Coronary arterial abnormalities were identified in 45.8%, including arterial stenoses, interruptions and ectasia in 7.6%. Ebstein's malformation coexisted in 18 patients. Median tricuspid valvar size and RV inlet Z-scores were -5.2 and -5.1, respectively. CONCLUSIONS: This study provides unique data on the diverse pathology of PAIVS in an unselected population. This will help determine if published reports reflect the true spectrum of pathology of the condition. 相似文献
20.