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981.
Lymphocyte response in patients with head and neck cancer: effect of clinical stage and radiotherapy
VK Jenkins P Ray HN Ellis CM Griffiths RR Perry MH Olson 《Canadian Metallurgical Quarterly》1976,102(10):596-600
Ffty-three patients with head and neck cancer tested before radiation treatment to determine numbers of blood lymphocytes and immunologic responses to mitogens of lymphocytes in whole-blood cultures had mean values that were 19% to 26% less than values for healthy individuals. Thirty patients whose disease was in stages III or IV had values similar to those in 23 patients whose disease was in stages I or II. Values for 45 patients tested at end of radiotherapy decreased to about 50% of pretreatment values; however, patients with advanced lesions experienced greater decreases (to 24% to 50%) than patients with localized lesions (to 71% to 84%). Patients with advanced lesions usually received radiation to larger areas than patients with localized lesions; therefore, the extent of decline in laboratory values was most likely dependent on volume of tissue treated. 相似文献
982.
983.
1. The simultaneous effects of an intravenous glucose infusion on plasma urea, glucose and alanine kinetics were investigated in normal post-absorptive man. 2. The primed constant intravenous infusion of compounds labelled with stable isotopes, [15N2]urea, [6-2H]glucose and [3-13C]alanine, was used. 3. The rate of appearance of glucose and urea in the plasma was rapidly reduced by the 17.7 mumol min-1 kg-1 glucose infusion. 4. In contrast, during the glucose infusion there was an increased rate of appearance of alanine in the plasma, and an increased percentage of glucose carbon atoms derived from alanine. 5. Reduced production of glucose and urea during the glucose infusion was not due to decreased gluconeogenesis from alanine. 相似文献
984.
985.
GB Park PE Erdtmansky RR Brown MP Kullberg J Edelson 《Canadian Metallurgical Quarterly》1980,69(5):603-605
A GLC method, employing a nitrogen-phosphorus-sensitive detector, is described for the analysis of mepivacaine, bupivacaine, etidocaine, lidocaine, and tetracaine in biological fluids. The method is simple, reliable, and sensitive, with a practical limit of sensitivity of approximately 2.5 ng/ml, well below therapeutic plasma levels. Extensive start-up procedures and sample preparation are not required. 相似文献
986.
MJ Tonkon RR Miller AN DeMaria LA Vismara EA Amsterdam DT Mason 《Canadian Metallurgical Quarterly》1977,62(3):339-346
Peripheral blood lymphocytes from patients with all stages of untreated Hodgkin's disease and from normal healthy adults were shown to synthesize and release ferritin in vitro. Ferritin synthesis was confirmed by immunoelectrophoresis, double immunodiffusion and autoradiography. Hodgkin's disease lymphocytes synthesized ferritin 4.2 times faster and released it 2.4 times faster than did normal lymphocytes, whereas total protein synthesis was faster in normal lymphocytes. Patients with nodular sclerosis and perhaps those with absence of fever had the highest synthetic rates; however no relationship was observed between relative rates of lymphocyte ferritin synthesis and sex, age, anatomical stage and presence of splenic or hepatic involvement by tumor. Addition of iron to normal human lymphocytes produced little or no change in ferritin synthesis. These data indicate that part of the intracellular ferritin detected in peripheral blood lymphocytes from patients with Hodgkin's disease and from normal individuals resulted from de novo synthesis rather than from uptake and storage of serum ferritin, and suggests that elevated ferritin levels detected in the serum and tumor tissue of Hodgkin's disease patients originate from lymphocytes. 相似文献
987.
988.
A template DNA from phage lambdah80dlacp5 coding for the in vitro synthesis of beta-galactosidase was used to study the effect of DNA methylation by the alkylating agent, dimethyl sulfate (DMS). Increasing the levels of DMS up to 50 mM concentration in the incubation medium led to an increase of DNA methylation. When incubated for 10 min at 37 degrees C, 3-4% Of nucleotides were methylated. The increase was linear to about 0.6% nucleotide methylation level. A higher yield was obtained at 37 degrees C incubation temperature than at 20 degrees C. Methylation of lambdah80dlacp5 DNA alone without methylation of other factors in the incubation mixture caused inhibition of the synthesis of beta-galactosidase in vitro. Increasing levels of DNA methylation caused greater inhibition of the newly synthesized enzyme activity. Total protein and RNA synthesis was inhibited by the methylated DNA to a much lesser extent than the inhibition of enzyme activity. When the level of nucleotide methylation was 0.74%, only 2% of enzyme activity remained, but total protein and RNA synthetic activities were found to be 72% and 44%, respectively. 相似文献
989.
990.