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81.
J Calam  R J Unwin  J Singh  S Dorudi  W S Peart 《Peptides》1984,5(2):441-443
VIP containing nerves are present in the kidney and plasma VIP levels are elevated in cardiac failure and severe liver disease. We studied the effects of intravenous VIP; 6 pmol kg-1 min-1 on 6 normal subjects and 3 patients with liver disease. In normal subjects VIP produced flushing and significant rises in heart rate and pulse pressure but the clearance rates of paraaminohippurate and creatinine did not change significantly. Urine flow fell to about 1/3 and the rate of excretion of electrolytes (except phosphate) fell to about a half of control values. Plasma renin activity rose about 3-fold and there were significant rises in haematocrit and the plasma concentrations of solids, calcium and phosphate. The patients with liver disease responded similarly. Elevated plasma VIP could contribute to salt and water retention in disease states.  相似文献   
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Summary Cross-compatibility of species in section Arachis Krap. et Greg. nom. nud., and chromosome pairing and pollen fertility in their interspecific F1 hybrids were studied to further understand the phylogenetic relationships among these species. Except those with A. batizocoi Krap. et Greg. nom. nud., hybrids between diploid species have near normal bivalent frequency (9.1–9.8) and moderate to high pollen fertility (60–91%). Hybrids between A. batizocoi and other species have low bivalent frequency (5.2–6.9) and very low pollen fertility (3–7%). These results confirm the earlier separation of these species into two groups based on karyomorphology and Mahalanobis D2 calculated on arm ratios. These studies also provide a picture of relative affinities between A. batizocoi, the lone member of one cluster, and the other species, and among the rest of the species. They also indicate that the basic chromosome complement in the two groups of species is the same. Chromosome pairing in triploid hybrids, (A. hypogaea L. X diploid wild species), suggests that A. batizocoi is the closest diploid relative of A. hypogaea. It is closer to A. hypogaea subspecies fastigiata Waldron than to A. hypogaea subspecies hypogaea Krap. et. Rig. Other diploid species of the section Arachis are equidistant from A. hypogaea, and have the same genome which has strong homology to one of the genomes of A. hypogaea. Based on the present results, the two tetraploid species, A. monticola Krap. et Rig. and A. hypogaea can be recognised as two forms of the same species. Breeding implications have been discussed in the light of chromosome behaviour observed in hybrids of A. hypogaea X diploid species, and on the presumptions that A. hypogaea has an AABB genomic constitution, and that among the diploid species, the B genome is present in A. batizocoi while the A genome is common to the other diploid species of section Arachis.Submitted as Journal Article No. 328 by the International Crops Research Institute for the Semi-Arid Tropics (ICRISAT)  相似文献   
84.
Prolific shoot bud differentiation was induced in callus and suspension cultures of hypocotyl origin in Brassica campestris cv. Yellow Sarson on MS medium supplemented with K (13.9–23.2 M) or BA (13.3–22.1 M). Plantlets were obtained by rooting the in vitro differentiated shoots. Histological studies revealed a unique mode of meristemoid formation.Abbreviations MS Murashige and Skoog (1962) - 2,4-D 2,4-dichlorophenoxyacetic acid - BA Benzyladenine - IAA Indole-3-acetic acid - IBA Indolebutyric acid - K Kinetin - NAA Naphthalene acetic acid  相似文献   
85.
86.
In nonamended soil, vegetative growth and sporulation ofFusarium spp. were higher in the rhizosphere than in the soil. Sporulation was favoured by young plants and decreased with increasing plant age. Amendments with low C/N oil-cakes enhanced vegetative growth and sporulation in root-free soil. The extent of stimulation varied with the nature of organic matter used and the stage of its deoomposition. Sporulation was suppressed by castor cake and sawdust with urea amendments. Rhizosphere cf pea altered the effect of different amendments.  相似文献   
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1. ATP-dependent proton translocation and ATP-dependent quenching of the fluorescence of 9-aminoacridine were measured in inside-out vesicles derived from a cytochrome-deficient mutant of Escherichia coli. 2. ATP-dependent quenching of fluorescence was inhibited by nigericin gramicidin, NH4Cl, and carbonylcyanide-m-chlorophenylhydrazone. Inhibition was also produced by the ATPase inhibitors N,N'-dicyclohexylcarbodimide (DCCD) and diphenyl phosphorazidate (DPA), and by the respiratory chain inhibitors piericidin A, 2-heptyl-4-hydroxyquinoline N-oxide, and An2+. The inhibition of ATP-dependent fluorescence quenching by the ionophores, uncouplers, and respiratory chain inhibitors was not due to an effect on ATPase activity which was insensitive to these agents. 3. By use of the ATPase inhibitors DCCD and DPA, or by replacing ATP with GTP, ITP and CTP, a correlation between the ATPase activity and the rate of ATP-dependent membrane energization, as measured by fluorescence quenching, was obtained.  相似文献   
90.
Summary The concentration, uptake and element use efficiency of N, P and K in one C3 annual (Polypogon monspeliensis) and two C4 (Echinochloa colonum, an annual, andDichathium annulatum, a perennial) grasses were determined during winter and summer seasons in monocultures raised in field plots at three moisture levels,viz. full, half and one-fourth of field capacity. At each moisture regime the plants were clipped thrice at moderate and severe levels corresponding to 40 and 80% of live green. The concentration of these elements was characteristic of the growth habit of these plants;e.g. the build up of concentration was maximum in leaf of the annuals while it was comparable in crown and leaf of Dichanthium. The N level was maximum in Polypogon. The nutrient use effiency was comparable in the two annuals and maximum K and N use were obtained in Polypogon and Dichanthium, respectively.  相似文献   
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