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971.
Summary A malformed male newborn with partial trisomy for the distal part of the long arm chromosome 14 (14q2314qter) is described. This anomaly arose as a segregation product of a balanced t(14q-, 11q+), translocation in the father.  相似文献   
972.
Spontaneously hypertensive rats (SHR) have basal levels of plasma renin activity (PRA) lower than the ones observed in normal Sprague Dawley rats. Three beta blocking agents are orally administered to unanesthetized spontaneously hypertensive and normotensive rats. Propranolol and S 464 reduce PRA in spontaneously hypertensive and normotensive control rats. Pindolol do not lower PRA in normotensive rats but increases levels of PRA in spontaneously hypertensive rats. These results are discussed.  相似文献   
973.
Overlapping of the VP2-VP3 gene and the VP1 gene in the SV40 genome.   总被引:14,自引:0,他引:14  
The nucleotide sequence of the SV40 Hind E fragment has been determined mainly by the partial chemical degradation procedure of Maxam and Gilbert (1977). The sequence of the strand with the same polarity as the late messenger RNA shows only one open reading frame for translation. Considering that VP3 corresponds to the carbosyl terminal part of VP2, and considering various evidence which indicates that the SV40 Hind E segment is part of the amino acid sequence of VP2-VP3. It continues clockwise in Hind K, where it terminates with a UAA signal. The latter is located 110 nucleotides beyond the initiation signal for the major structural protein VP1 (Fiers et al., 1975; Van de Voorde et al., 1976). Hence this small overlapping region of the genome codes for the synthesis of three different proteins in two different reading frames. The deduced amino acid sequence covers a major part of the vp3 poly peptide, and the amino acid composition is in good agreement with published values (Greenaway and Levine, 1973).  相似文献   
974.
975.
Fructose metabolism in four Pseudomonas species   总被引:1,自引:0,他引:1  
1. ATP-Dependent phosphorylation of fructose could not be detected in extracts of fructose-grown cells of Pseudomonas extorquens strain 16, Pseudomonas 3A2, Pseudomonas acidovorans and Pseudomonas fluorescens. Instead, phosphorylation of fructose to fructose-1-phosphate was found to occur when cell-free extracts were incubated with fructose and phosphoenolpyruvate. Such an activity could not be detected in cell-free extracts of succinate-grown cells. 2. High levels of 1-phosphofructokinase were found in extracts of the above organisms when growth on fructose. 3. Mutants of Pseudomonas extorquens strain 16 lacking 1-phosphofructokinase were unable to grow on fructose. Revertants to growth on fructose had regained the capacity to synthesize this enzyme, indicating its necessary involvement in fructose metabolism. 4. A survey has been carried out of enzymes involved in carbohydrate metabolism in the species listed above.  相似文献   
976.
Investigation of about 50 Senecio species has afforded many new substances, in addition to known compounds. Present in these plants are 23 fura  相似文献   
977.
Summary Immunostaining of thin serial paraffin sections has shown that somatostatin is present in the same parafollicular cells as calcitonin in the adult rat thyroid gland. The number of cells containing both peptides is much smaller than the number containing calcitonin but not somatostatin.  相似文献   
978.
Escherichia coli nucleoids were visualized in a compact, highly supercoiled conformation at 1 M NaCl. After the salt concentration was lowered to 0.15 M NaCl, the nucleoids uncoiled in beaded fibers in which RNA-mediated structural domains could be distinguished.  相似文献   
979.
980.
Brain tissue pH was measured in cats at normocapnia hypocapnia, hypercapnia, and death from anoxia using a pH sensitive fluorescent indicator (umbelliferone) with both molecular and ionic fluorophors. A ratio analysis of the indicator's calibrated 450 nm fluorescent tissue washout curves from 340 and 370 nm excitation permitted direct determinations using a nomogram. Possible errors in these measurements related to differential quenching, absorption, and changes in the redox state of the indicator were investigated in vitro and in vivo for brain tissue and blood. In animals with preserved autoregulation, brain pH varied linearly with arterial pH (art pH 7.0, brain pH 6.98: art pH 7.4, brain pH 7.24). Brain pH at death fell to 6.68. An analysis of the indicator clearance curves suggests these measurements reflect a component of the intracellular space and the lipid solubility of the indicator suggests this is a membranous component.  相似文献   
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