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991.
Alkaline phosphatase activity of rat serum was reduced 50% by fasting the animal for 24 hours. Diabetes, induced by alloxan or streptozotocin, increased serum alkaline phosphatase 3- to 5-fold in fed rats and the elevated activity was reduced by insulin administration. In the absence of insulin, fasting alone was able to reduce the serum alkaline phosphatase of diabetic rats to control values. The elevated serum isozyme was found to be of intestinal origin by the use of appropriate inhibitors and electrophoretic mobility following neuraminidase treatment. It is concluded that food intake, particularly the hyperphagia of diabetes, plays a major role in regulating the concentration of intestine and serum alkaline phosphatase in the rat.  相似文献   
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Translation of polyadenylated mRNA of Chlamydomonas reinhardtii in a cell-free wheat germ system resulted in the synthesis of numerous discrete polypeptides. Among them was a species with molecular weight 20,000 that was immunoprecipitated specifically by antibodies raised against the authentic small subunit (16,500 daltons) of ribulose-1,5-bisphosphate carboxylase [3-phospho-D-glycerate carboxy-lyase(dimerizing), EC 4.1.1.39]. Since the immunoprecipitated polypeptide has a larger molecular weight by approximately 3500 than the small subunit (S) it was identified as a putative biosynthetic precursor (pS). Post-translational conversion of pS by a specific endoprotease yielded two detectable products: one apparently identical in size to S and the other, a small peptide, presumably representing the remainder of pS. The endoprotease requires sulfhydryl groups for its activity and is present in a C. reinhardtii postribosomal supernatant as well as in a free polysome fraction. The latter could account for the observation that completion of nascent chains in free polysomes yielded S but not pS. We propose that pS is an extrachloroplastic form of S and that the small peptide portion plays a role in the transfer of S into the chloroplast.  相似文献   
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A total of 1,394 patients with non-Hodgkin's lymphoma were treated at the Princess Margaret Hospital between January 1, 1967 and December 31, 1978. Overall actuarial survival of 525 patients with nodular lymphomas was 40% at 12 years; survival of patients with localized (Stage I & III) nodular lymphomas treated with radical radiation therapy was 58%. Significant prognostic factors defined by multivariate analysis included patient's age, stage, histology, tumor bulk, and presence of B symptoms. By combining prognostic factors we have identified distinct prognostic groups within the overall population. Patients with Stage I & II disease, small or medium bulk, less than 70 years of age achieved 92% 12 year actuarial survival and a 73% relapse-free rate in 12 years of follow-up. These patients represent groups highly curable with irradiation.  相似文献   
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Studies were made in urine obtained from people attending for routine measurement of blood pressure in a screening programme. Subjects with diastolic blood pressure between 95 and 109 mm Hg excreted significantly more sodium than the group with diastolic blood pressure below 90 mm Hg. Urine volumes, potassium excretion and creatinine excretion did not differ significantly between the groups.  相似文献   
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