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VP Strekalovski? 《Canadian Metallurgical Quarterly》1983,29(1):27-29
The rates of colonic tumor growth were studied on the basis of evaluation of the case histories of 19 cancer patients in whom dynamic endocolonoscopy had been carried out. In some cases, malignant tumors appeared in the colon within 12 months after previous colonoscopy. Tumors were under 2.0 cm in size and were not accompanied by any clinical symptoms. Repeated endoscopic examinations performed within a period of 1-3 years detected large tumors which caused the constriction of colonic lumen. Clinical symptoms developed in such patients approximately 1-4 months prior to tumor detection. It is concluded that although the rates of growth of colonic malignancies are rather high, tumorigenesis is preceded by a long-term stage of preclinical disease. 相似文献
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The effects of anemia during lead exposures were studied using an infant baboon animal model. When the hemoglobin concentration was reduced to less than 70% of normal, a marked blood lead increase was observed and the free erythrocyte porphyrin value, aminolevulinic acid dehydratase activity and reticulocyte counts increased. Special emphasis should be placed on nutritional effects in lead exposures. 相似文献
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A Seamster T Mead J Gislason K Jackson F Ruddy BD Pate 《Canadian Metallurgical Quarterly》1976,21(4):868-882
Fingerprint lifting tape has been applied to the lifting of firearms discharge residue from various surfaces. Lifting efficiencies from coarse fabric ranged from 30 to 70%. Use of the technique has been demonstrated in identifying a bullet hole and in measuring residue patterns on floor and firing hand surfaces. In hand lifts it has been shown that autoradiography alone does not uniquely distinguish the hand of someone who has fired a revolver from the hand of someone who has not. Neutron activation analysis of lifts from selected hand areas may, however, provide such a distinction. 相似文献
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II Gitel'zon VP Nefedov VV Mezhevikin VA Samo?lov IuV Kotlovski? 《Canadian Metallurgical Quarterly》1977,84(7):23-24
Hypoxemia (45-minute) influence in vivo on erythropoietic activity of the kidney, liver, spleen, and sternum was studied by normoxemic perfusion of the isolated organs. The erythropoietic activity proved to increase after 6-hour perfusion of the liver; this confirmed the participation of this organ in the extrarenal secretion of the erythropoietic factor. 相似文献
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IA Kostanyan EV Navolotskaya RI Nurieva VP Zav'ialov VM Lipkin 《Canadian Metallurgical Quarterly》1997,23(10):805-808
A specific interaction of [3H]Glu with T lymphocytes from the blood of healthy donors (Kd = 0.236 microM) was revealed and described. It was found that unlabeled quisqualate, a structural analogue of L-glutamic acid, and unlabeled dipeptides Ala-Glu, Glu-Ala, and Glu-Glu competitively inhibit the specific binding of [3H]Glu to T lymphocytes (with Ki 0.19, 2.4, 3.4, and 1.2 microM, respectively). Binding experiments with conjugates of labeled and unlabeled glutamic acid with dextran showed that the receptors of [3H]Glu are localized on the outer surface of the plasma membrane of T lymphocytes. 相似文献