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91.
Edwin B. Smith 《Brittonia》1983,35(2):164-169
92.
93.
Metabolic acidosis produces a phosphaturia which is independent of parathyroid hormone or dietary phosphorus intake. To study the underlying mechanism, inorganic phosphate (Pi) and glucose transport were studied in brush-border membrane vesicles prepared from the renal cortex of parathyroidectomized rats gavaged for three days with either 7.5 ml of 1.6% NaCl (control) or 1.5% NH4Cl (acidosis). At killing, blood pH and plasma bicarbonate were and , respectively, in control and () and () in acidotic rats. Serum Pi was similar in both groups, while 24 h urine Pi excretion was higher in the acidotic group (). Peak sodium-dependent uptake of Pi, measured after 1.5 min of incubation, was higher in controls than acidotic rats ( vs. protein, ), whereas peak glucose uptake at 1.5 min was not significantly different between the groups. Equilibrium values for Pi and glucose uptake were similar in the two groups. for Pi uptake in the control and acidotic animals were not different, 0.036 and 0.040 mM, respectively. By contrast, was higher in controls than in the acidotic group, 3.13 vs. 1.15 nmol/mg protein per 15 s. These results suggest that metabolic acidosis directly inhibits Pi uptake by the brush border of the proximal tubule by decreasing the availability of Pi carriers of the renal brush-border membrane. 相似文献
94.
Three photosynthetic enzymes were characterised in extractsfrom leaves and aerial roots of Aranda Christine 130.The enzymes from both tissues were similar in activity and kineticproperties. Grana-containing chloroplasts were found in rootcells of Vanda suauis. Thus components crucial to photosynthesisare present in aerial roots of these leafy orchids. (Received March 22, 1983; Accepted July 7, 1983) 相似文献
95.
B. Edwin Blaisdell 《Journal of molecular evolution》1983,19(2):122-133
Summary Coding sequences of eucaryotic nuclear DNA were characterized by an excess of short runs and a deficit of long runs of weak
and of strong hydrogen bonding bases; non-coding sequences by a deficit of short runs and an excess of long runs, in the same
of purines and of pyrimidines. The conservation of these attributes across DNA sequences coding for proteins of widely different
function, across widely different eucaryotic species for the same protein and across related genes that diverged a long time
ago and that now show large differences in base and, if coding, amino acid sequence suggested that these attributes have survival
value. It was concluded that these attributes constitute probalistic constraints on th primary structure (base sequence) of
both coding and non-coding DNA. 相似文献
96.
Mycoplasma, in particular species laidlawii and gallisepticum, are found to have a very small, low frequency conductivity as would be predicted by the dielectric model for bacteria and their apparent lack of cell wall structure. Membrane capacitance values for the two organisms are both about 0.9 μF/cm2, although electron micrographs show that the membrane of M. gallisepticum is 20-40 A thicker than that of M. laidlawii. 相似文献
97.
D G Davis T R Lindstrom N H Mock J J Baldassare S Charache R T Jones C Ho 《Journal of molecular biology》1971,60(1):101-111
98.
99.
Population dynamics of microfilarial production and eosinophilic levels in slow lorises infected with Breinlia sergenti, Petter (Filarioidea: Dipetalonematidae). International Journal for Parsitology 4: 383388. Observations have been made on microfilarial and eosinophilic levels in slow lorises infected with Breinlia sergenti. Animals given a single inoculation of 100-150 infective larvae exhibited three different patterns of microfilaraemia while superinfected animals showed enhanced microfilarial levels. It appeared that the number of inoculations as well as the interval between inocula are important factors in enhancing microfilarial levels. Two different types of incubation periods were seen, one at 100-120 days and the other at 200 days. The eosinophilic levels were investigated in some of the animals and an attempt was made to correlate these levels with the microfilaraemia. Cortisone injection appeared to promote a vigorous eosinophilia in some of the infected animals tested. 相似文献
100.
Edwin B. Smith 《Brittonia》1973,25(2):200-208
On the basis of morphological, hybridization, genetic, and field studies, it is proposed thatCoreopsis saxicola Alex. be reduced to varietal rank asC. grandiflora var. saxicola. 相似文献