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991.
992.
The amount of connective tissue present, relative to the amount of parenchymal tissue, has been assessed in a random series of 200 livers from children dying from non-hepatic disease. The amount of connective tissue in the left liver is approximately twice that in the right liver. The connective tissue in both lobes progressively diminishes during childhood but at all times remains higher than that in adults.Increased amounts of connective tissue in the liver in children is probably non-specific and related to the degree and duration of shock and hypoxia in the immediate postnatal period. 相似文献
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997.
The major mechanism by which the serotonin neurotoxin 5,6-dihydroxytryptamine (5,6-DHT) expresses its neurodegenerative action may involve alkylation of biological nucleophiles by the electrophilic quinoid autoxidation products. To determine the relative importance of various sites on these autoxidation products toward alkylation we have rationally designed and synthesized 4-Me-5,6-DHT (16a), 7-Me-5,6-DHT (16b), and 4,7-Me2-5,6-DHT (16c). The indole nucleus of these analogues was constructed by the reductive cyclization of the corresponding 2, beta-dinitrostyrenes, and the aminoethyl side chain was introduced via gramine methiodides. Redox data showed that all the analogues are more readily oxidized compared to 5,6-DHT. The biological activity was evaluated in differentiated neuroblastoma N-2a cells in culture. The order of inhibitory potency, as determined by measuring the inhibition of incorporation of [3H]thymidine into DNA, was 16c much greater than 16a greater than 5,6-DHT approximately equal to 16b. The order of affinity (expressed as IC50 values in microM) for serotonergic uptake as determined by measuring their inhibition of [3H]-5-HT uptake was 5,6-DHT (4) greater than 16c (20) greater than 16a (23) greater than 16b (52). The results of these studies established that these rationally designed C-methylated analogues of 5,6-DHT are suitable probes for elucidating the molecular mechanism of action of 5,6-DHT. 相似文献
998.
Selective plane removal in limited angle tomographic imaging 总被引:1,自引:0,他引:1
A method of improving a planar image in limited angle tomography by removing blurred image information from selected out-of-focus planes is discussed. Focused tomosynthesized images rather than individual projections are used. The necessary equations for removing the information from either two or four adjacent planes, produced with a symmetrical, but otherwise arbitrary blurring function, are developed and specialized to the geometry of circular tomography. Results of a phantom experiment illustrating the technique are presented. 相似文献
999.
Prediction of early metastases in individual patients has been attempted by combined evaluation of a battery of recognised parameters such as blood vessel invasion (BVI) of tumor cells, Barr body frequency (BBF), plasminogen activator (PA), collagenase, estradiol receptors (ER), progesterone receptors (PgR), and peroxidase activity (PRA) in 18 malignant and 3 benign (control) breast tumors. Since breast tumor cells spread through the blood vessels, the cases were divided into BVI (+) and BVI (-) groups. Results show that in the former group, all the cases had poor prognosis and two even had distant metastases within one year. In BVI (-) group, 9 out of 12 appeared to have good prognosis. 相似文献
1000.
P. Ghosh 《Indian journal of otolaryngology and head and neck surgery》1985,37(2):67-68
A case of sub-total destruction of pinna is presented in this report in which reconstruction was done using costal cartilage and local skin flap with good result. 相似文献