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21.
Single photon emission computed tomography using 99mTc-HM-PAO in the routine evaluation of Alzheimer's disease 总被引:1,自引:0,他引:1
T A Hurwitz W Ammann D Chu C Clark J Holden R Brownstone 《The Canadian journal of neurological sciences. Le journal canadien des sciences neurologiques》1991,18(1):59-62
Regional cerebral blood flow was studied in 7 patients with clinically suspected Alzheimer's disease and 10 normal controls by single photon computed emission tomography (SPECT) using HM-PAO. All patients with Alzheimer's disease and no controls had parietal lobe hypoperfusion which was usually bilateral. In patients with more severe dementia hypoperfusion extended into the frontal lobes. Parietal lobe hypoperfusion corresponds to parietal lobe degeneration which is the one of the first neocortical regions to show the typical degenerative changes of Alzheimer's disease. SPECT with HM-PAO is a non-invasive investigation available in most nuclear medicine departments and complements existing tests in the routine evaluation of patients presenting with dementia. 相似文献
22.
W W Huurman F S Jacobsen J C Anderson W K Chu 《The Journal of bone and joint surgery. American volume》1987,69(5):699-705
A simple, rapid, and accurate method for measuring limb-length discrepancies with computerized axial tomographic equipment is described. With this method less irradiation is delivered and some of the errors of computation are eliminated, compared with conventional methods. The costs of the technique are comparable with those of scanograms. The method is particularly applicable in the patient who has contracture of a joint. 相似文献
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24.
无创性动态血压(ABPM)能较客观地反映血压水平及其昼夜变化规律,对高血压病的诊断、指导用药、药物疗效的评定以及预后评估等均有较大价值。本文对ABPM的发展及临床应用等问题进行综述。 相似文献
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H. W. Chu S. Balzar J. Y. Westcott J. B. Trudeau Y. Sun D. J. Conrad S. E. Wenzel 《Clinical and experimental allergy》2002,32(11):1558-1565
BACKGROUND: Although 15(S)-hydroxyeicosatetraenoic acid (15(S)-HETE), a product of 15-lipoxygenase (15-LO), may be involved in mild to moderate asthma, little is known about its potential roles in severe asthma. OBJECTIVES: This study was performed to evaluate 15(S)-HETE levels in bronchoalveolar lavage fluid (BALF) from severe asthmatics with and without airway eosinophils and from the control groups. In addition, 15-LO protein expression was examined in endobronchial biopsy, while its expression and activation were evaluated in BAL cells. RESULTS: While 15(S)-HETE levels in BALF were significantly higher in all severe asthmatics than normal subjects, severe asthmatics with airway eosinophils had the highest levels compared with mild, moderate asthmatics and normal subjects. 15(S)-HETE levels were associated with tissue eosinophil numbers, sub-basement membrane thickness and BALF tissue inhibitor of metalloproteinase-1 levels, and were accompanied by increased 15-LO expression in bronchial epithelium. In addition, activation of 15-LO was suggested by the increased proportion of 15-LO in the cytoplasmic membrane of alveolar macrophages from severe asthmatics. CONCLUSION: The data suggest that severe asthmatics with persistent airway eosinophils manifest high levels of 15(S)-HETE in BALF, which may be associated with airway fibrosis. It is likely that 15-LO expression and activation by airway cells explain the increased 15(S)-HETE levels. 相似文献
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C E Chu A Cooke J B Stephenson J L Tolmie B Clarke W L Parry-Jones J M Connor M D Donaldson 《Archives of disease in childhood》1994,71(5):441-442
Thirty one patients with the putative diagnosis of Prader-Willi syndrome were reassessed clinically and by DNA analysis. Eleven patients were judged not to have Prader-Willi syndrome and 20 to have the condition. This was confirmed by DNA analysis in all but one case. The diagnosis of Prader-Willi syndrome, especially in early infancy, should be made with caution unless confirmed by molecular genetic studies. 相似文献
29.
There is a great deal of indirect, nonexperimental evidence that a pattern of earlier-stage disease at diagnosis has a better outcome. Increased early detection activities can change, these stage patterns while various biases and the question of generalizability need to be kept in mind in their interpretation. The indirect evidences of possible benefit from early detection activities includes an increase in the number of cases detected, a pattern of more early- and less advanced-stage cases, an increase in the overall site-specific survival rate, and a decrease in the case fatality rate. Unless these intermediate markers are favorable, it is unlikely that early detection will reduce mortality. In addition, one should also differentiate a reduced incidence or a change in treatment as a cause for reduced mortality. 相似文献
30.
The role of various subfamilies of rat hepatic cytochrome P450 in the oxidation of ethosuximide was evaluated by comparing ethosuximide clearance in control rats and those pretreated with relatively selective P450 inducers and/or inhibitors. Clotrimazole pretreatment increased ethosuximide clearance threefold (p less than 0.005). Dexamethasone increased ethosuximide clearance twofold (p less than 0.001), and the dexamethasone effect was completely abolished by a single dose of triacetyloleandomycin. These results suggest a prominent role for cytochrome P450IIIA in ethosuximide metabolism in the rat. Isoniazid increased ethosuximide clearance twofold (p less than 0.001), and this effect was abolished by a single dose of diallylsulfide, suggesting that ethosuximide is also processed by cytochrome P450IIE1 in rats. Phenobarbital pretreatment increased ethosuximide clearance 2-2.7 fold (p less than 0.001); an effect that was only partially reversed by orphenadrine, an inhibitor of cytochrome P450IIB/IIC enzymes. This suggests a quantitatively less important role for the IIB/IIC subfamilies in processing ethosuximide, since phenobarbital is an inducer of P450 subfamilies IIB, IIC, IIE, and IIIA. Neither the cytochrome P450IA inducer, beta-naphthoflavone, nor the inhibitor, alpha-naphthoflavone altered ethosuximide clearance. Ajmaline, an inhibitor of cytochrome P450IID, had no effect on ethosuximide clearance. Together, these findings suggest that ethosuximide is principally oxidized by cytochrome P450IIIA, and that cytochrome P450IIE may play an important role. Cytochromes P450IIB/C play less prominent roles in ethosuximide oxidation, and neither cytochrome P450IA nor cytochrome P450IID is involved. 相似文献