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11.
The dbl oncogene was initially isolated from a human diffuse B-cell lymphoma. Antisera from mice bearing tumors induced by this oncogene specifically detected a protein of about 66 kDa (p66) in dbl transformants. dbl cDNA-selected poly(A)+ RNA isolated from a transfectant clone expressing p66 directed the in vitro synthesis of this protein, establishing that it is encoded by dbl. Subcellular localization studies revealed that p66 is a cytoplasmic protein distributed between cytosol and crude membrane fractions. Moreover, p66 was shown to be a phosphoprotein, with phosphorylation specific to serine residues. Our characterization of the dbl-encoded protein appears to distinguish this transforming gene product from those of other known oncogenes.  相似文献   
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Sixteen new compounds 2-methylamino substituted phenyl-3-substituted anilino 4 (3H) quinazolinones (3-18) were prepared. All the compounds were evaluated for their antiparkinsonian activity and compared with bromocriptine. Compounds 10,15 and 18 showed better activity. These compounds also bind with the dopamine receptors in striatal membrane preparations of rat brain.  相似文献   
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One hundred and five patients with discrete breast lumps were examined with a 10 MHz Doppler ultrasonic flowmeter. Doppler flow signals were analysed on an Angioscan spectrum analyser. Recordings from the opposite normal breast were taken as controls and signals from the two sides compared. In 23 patients signals from the normal breast could not be recorded and therefore results of the remaining 82 patients are reported. These included 39 patients with carcinoma, 20 with fibroadenoma, 12 with cyclical nodularity and 11 with cysts. Malignant lumps exhibited significantly higher peak systolic (S) and minimum diastolic frequencies (D) in comparison to the control breast. Fibroadenoma also had a higher S and D than those of the opposite normal breast. Signals over cysts and cyclical nodularity showed no significant difference from the recordings over the control side. Despite significantly higher systolic and diastolic frequencies in the cancer group in comparison to benign lumps and normal breast, considerable overlap in the values was seen between cancer and other groups. Therefore the patterns on 10 MHz Doppler sonography are not sufficiently specific to discriminate benign from malignant breast lumps.  相似文献   
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Adult worms of Acanthocheilonema viteae were found to be susceptible to the reactive oxygen intermediates (ROI) generated by the xanthine-xanthine oxidase (X-XO) system. The damage caused by this system was completely abolished by superoxide dismutase (SOD) and catalase but not by mannitol. The results, therefore, suggest that superoxide anions (O2-) and hydrogen peroxide (H2O2) alone or in combination might be toxic to the filariid. A. viteae exhibited the presence of an active enzyme system to protect itself against the oxidants. SOD and catalase were present in high levels of activities and appeared to constitute the major defence system. The role of glutathione peroxidase (GPx), on the other hand, seemed less important due to the weak activities of glutathione reductase (GR) and glucose-6-phosphate dehydrogenase (G6PDH). A. viteae also released SOD, catalase and GPx in the ambient medium, which appear useful in protecting the filariid against ROI generated by the host in the immediate surroundings of the parasite. Antifilarial agents, diethylcarbamazine (DEC) and 2,2'-dicarbomethoxylamino-5,5'-dibenzimidazolyl ketone (82/437) appreciably inhibited catalase and GPx of A. viteae. Inhibition of these enzymes appears to render the parasite prone to H2O2 toxicity leading to death. No adverse effect on antioxidant enzymes of liver, lungs and subcutaneous tissue of Mastomys natalensis recorded as a result of exposure to 82/437 suggests a non-toxic nature to the compound.  相似文献   
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A method is described for successfully establishing caecal amoebiasis in hamsters which were not fed and which were pretreated with 1 ml of magnesium sulphate every 24 hours for three days and then given 12 x 10(5) trophozoites of the HM-1 axenic strain or 18 x 10(5) trophozoites of the HK-9 axenic strain of Entamoeba histolytica by the oral route. All the animals developed diarrhoea within 24 hours of infection. When the animals were killed on the fifth day after infection the caecum was swollen and fused. Large macroscopic ulcers full of pus could be seen in the caecum. None of the control animals showed any of the changes mentioned above.  相似文献   
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Technical Quinalphos was administered po to pregnant rats through day 6-20 of gestation at doses of 0.5 or 1.5 mg/kg body weight. Quinalphos produced enzymatic changes in liver and serum of dams associated with mild pathomorphological changes in liver and brain. Fetotoxic effects were not observed at the tested dose levels as determined by total number of implantations, percentage resorption, live fetuses, crown rump length and fetal weight. A few insignificant skeletal deformities were noticed. A significant inhibition of acetylcholinesterase activity in fetal brain and placenta indicated possible transmigration of quinalphos from dams to fetuses.  相似文献   
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