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排序方式: 共有1605条查询结果,搜索用时 15 毫秒
1.
D Galasko T Saitoh Y Xia LJ Thal R Katzman LR Hill L Hansen 《Canadian Metallurgical Quarterly》1994,44(10):1950-1951
We determined apolipoprotein E (ApoE) genotypes in 122 autopsied demented patients. The frequency of the ApoE epsilon 4 allele was 39.6% in Alzheimer's disease (AD), 29.0% in the Lewy body variant of AD (LBV), and 6.25% in diffuse Lewy body disease. For AD and LBV patients, the epsilon 4 frequency was significantly higher than that reported in nondemented controls (10 to 15%). Therefore, LBV and AD share ApoE epsilon 4 as a genetic risk factor, providing further evidence that these conditions overlap. 相似文献
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Yield Stress and Microstructure of Set Yogurt Made from High Hydrostatic Pressure-Treated Full Fat Milk 总被引:1,自引:0,他引:1
F. Harte M. Amonte L. Luedecke B.G. Swanson G.V. Barbosa-Cánovas 《Journal of food science》2002,67(6):2245-2250
ABSTRACT: Set yogurts were prepared from fortified milk subjected to the following processes: (a) Thermal process (85C,°C,35 min), (b) High hydrostatic pressure process (193 or 676 MPa for 5 or 30 min), and (c) Nonprocessed milk (control). Yogurts from milk treated with 676 MPa for 30 min exhibited similar yield stress and water-holding capacity (WHC) to yogurts from heated milk. Transmission Electron Microscopy (TEM) micrographs exhibited small round casein micelle aggregates without appendages in yogurts from heated milk. Yogurts from milk treated with 193 MPa and untreated milk exhibited low yield stress, low WHC, and large clusters of coalesced micelles. Mechanisms for gel formation are discussed. 相似文献
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SA Cook RT Bronson LR Donahue N Ben-Arie MT Davisson 《Canadian Metallurgical Quarterly》1997,8(2):108-112
OBJECTIVE: To discuss the case of an 8-yr-old boy with an aneurysmal bone cyst of the right proximal humerus, including the features imaged on plain film radiography, computed tomography (CT), magnetic resonance imaging (MRI), including spin echo and fast field echo imaging. CLINICAL FEATURES: The patient suffered for 1 yr from intermittent but progressive pain in his right upper arm and shoulder area. There was no history of trauma or known systemic disease. There was decreased range of motion in abduction of the glenohumeral joint and pain on focal pressure along the deltoid muscle. A complete imaging evaluation consisting of plain film radiography, CT and MRI was performed, which revealed the classical imaging features of an aneurysmal bone cyst. An additional cystic lesion was detected by the MRI that was not appreciated on the plain films or CT. INTERVENTION AND OUTCOME: The patient was referred for biopsy to confirm the preliminary diagnosis of aneurysmal bone cyst. No treatment was instituted. CONCLUSION: Evaluation of aneurysmal bone cyst may be completed with CT scanning and more specifically with MRI MRI coronal T2, weighted images are advantageous for visualization of the main cystic lesion and any additional cysts. Fast field echo images show a better contrast between the cyst and bone marrow with extension of the cyst into the epiphysis as evident in this case. Follow-up studies revealed complete healing of the cyst with only residual densities in the humeral metaphyseal area. 相似文献
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Previous results, using a passive transfer assay, have shown that recrudescences of Plasmodium chabaudi chabaudi AS strain are antigenically different from the infecting parental population and also that the recrudescence appears to be a mix of antigenic types. This present study examines further these recrudescent populations using an indirect fluorescent antibody test on live, schizont-infected red blood cells. This analysis shows that ten clones derived from a recrudescence are all antigenically different from the parent population and that some are different from each other. The use of this method to examine the antigenic types of recrudescent clones after transmission through mosquitoes also demonstrates a resulting change in antigenicity. Such results showing a link between mosquito transmission and varying antigenicity may have important implications in terms of immunity and vaccine development. 相似文献
8.
H Lee KB Idler P Swanson JJ Aparicio KK Chin JP Lax M Nguyen T Mann G Leckie A Zanetti 《Canadian Metallurgical Quarterly》1993,196(1):57-69
Seven cardiac electrophysiology stimulators from four manufacturers (Biotronik, Bloom, Digitimer and Medtronic) in common current use are reviewed. The stimulators differ in the features provided and the design adopted to achieve these features. The number of output channels ranges from one to four, the number of extra-stimuli available ranges from two to six, and these can be delivered as a variety of sequences. Some of the stimulators (Digitimer and Bloom) are modular while others (Biotronik and Medtronic 532 series) are of an integrated design comprising a single physical unit. The design of the Medtronic EP-2 has both integrated and modular characteristics. The features of the stimulators associated with input, output, control and the user interface are specifically reviewed. The features are also compared against the published recommendations of the American Heart Association. In addition, a summary of stimulator user comments from a number of electrophysiology centres is presented. All of the stimulators fulfil, or are close to fulfilling, basic electrophysiological requirements, but some provide more complex facilities such as would be required by specialist centres. 相似文献
9.
Haemangiopericytoma of nose and paranasal sinuses is relatively uncommon tumour. It occurs in adults in sixth and seventh decades of life. In view of paucity of intranasal haemangiopericytoma old in Indian literature and young age of patient, we are reporting one case in 28-year-old female who presented with recurrent, profuse epistaxis. 相似文献
10.
LR Margraf 《Canadian Metallurgical Quarterly》1996,16(1):155-160
The prognostic value of p53 protein in tumor extracts as measured by ELISA was studied retrospectively in 228 non-small cell lung cancer (NSCLC) patients. The assay measures both wild-type and mutated p53. The specimens on which this study was performed have been used earlier to analyze the prognostic impact of components of the plasminogen activation system, which enabled an analysis of relationships between these components and p53 protein. The median of the p53 protein values in the 228 patients was 0.10 (range, 0-0.70) ng/mg protein. Survival analysis comparing patients with p53 levels below versus above the median showed no significant difference (P = 0.67). When analyzing the histological types, adenocarcinoma (n = 106), squamous cell carcinoma (n = 84), and large cell carcinoma of the lung (n = 38) separately, similarly, no significant differences in survival between patients having low versus high tumor p53 levels were found. When comparing levels of p53 protein in the three histological types, a significant difference (P < 0.0001) was found, with adenocarcinomas having the lowest levels. There was a weak positive correlation (r = 0.22) between p53 protein and plasminogen activator inhibitor type 1 (PAI-1). Multivariate analysis proved no impact of p53 on survival; tumor size, PAI-1, and lymph node involvement were the only variables with significant influence on survival. These data indicate that p53 protein quantitated with a sandwich ELISA in tumor extracts from NSCLC has no prognostic value, but the observed statistically significant difference of p53 protein content between histological subgroups may be related to differences in etiology and biology in different NSCLC subtypes. In addition, the weak association found between p53 protein and the independent prognostic marker PAI-1 could suggest yet undefined interactions in lung cancer. 相似文献