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1.
Rats treated with chlorpromazine (CPZ) (1 mg/kg/day i.p.) experienced a marked decline in cerebral insulin levels (0.057 +/- 0.01 ng/g wet weight) with respect to a control group (0.38 +/- 0.05 ng/g wet weight), while rats given D-amphetamine bitartrate (AMPH) chronically (20 mg/kg/day p.o.) showed a rise in cerebral insulin (0.55 +/- 0.04 ng/g wet weight). Combined treatment with both drugs at the same dosages produced lower cerebral insulin levels (0.46 +/- 0.10 ng/g wet weight) than in the AMPH animals. In the groups of rats treated with CPZ and with AMPH + CPZ, there was a slight elevation in serum insulin levels. Serum glucose values did not vary. 相似文献
2.
S Sonnino D Acquotti G Fronza L Cantù V Chigorno M Pitto G Kirschner G Tettamanti 《Chemistry and physics of lipids》1988,46(3):181-191
N-Glycolylneuraminic acid containing GM1, GM1(NeuGc), was prepared by semisynthetic procedure. The procedure makes use of GM1 ganglioside deacetylated at the level of sialic acid residue (deAc-GM1) and of 1,3-dioxalan-2,4-dione. DeAc-GM1 is prepared from GM1 by alkaline hydrolysis in the presence of tetramethylammonium hydroxide and the glycolylating compound by reaction of glycolic acid with phosgene in dioxane, followed by cyclization under vacuum. Mass spectrometric and nuclear magnetic resonance spectroscopy analyses clearly indicated the presence, in the neosynthesized ganglioside of a glycolic group in the sialic acid residue. Laser-light scattering measurements show that GM1(NeuGc) aggregates in aqueous media being present in solution as micelles with a molecular weight of 576,000 and a hydrodynamic radius of 62.4 A as determined at 25 degrees C. GM1(NeuGc) promotes neurite outgrowth in N-2a cells to a similar degree as GM1(NeuAc), but shows different behaviour under treatment with sialidase from Arthrobacter ureafaciens. 相似文献
3.
F Rivas D García-Cruz H Rivera M L Plascencia R M González J M Cantú 《Annales de génétique》1985,28(2):113-115
A 2 4/12-year-old girl whith a de novo 46,XX,-22 + der(22), t(19;22)(q13.2;p11) karyotype is described. From this and other eight similar cases previously published, a typical phenotype in distal 19q trisomy is concluded. 相似文献
4.
Forty nine eczematous infants who were still solely and exclusively breast fed and who had never received anything but breast milk were studied for evidence of sensitisation to foods. Thirty four similar infants without eczema formed a control group. The eczematous infants were divided into three groups according to clinical criteria: (1) definite atopic eczema; (2) possible atopic eczema; (3) atopic eczema unlikely. Twenty three infants showed cutaneous hypersensitivity to foods, usually egg and cows'' milk. Seven of 14 infants in group 1 and nine of 20 in group 2 were sensitised compared with four of 15 in group 3 and three of 34 controls (p less than 0.01). Ovalbumin was detected in breast milk from 14 of 19 mothers tested after ingestion of egg, the concentrations being the same for mothers feeding eczematous and normal infants. Breast fed babies developing eczema may be sensitised by foods eaten by their mothers. 相似文献
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6.
Thirty seven breast fed infants with eczema were studied to see whether changes in their mothers'' diets affected their skin condition. Nineteen mothers and babies took part in a double blind crossover trial of exclusion of egg and cows'' milk, and 18 took part in open exclusion of 11 foods followed by double blind challenge to those mothers whose infants seemed to respond. Babies were examined at the beginning and end of each dietary period, and the extent and severity of the rash were given a numerical score. The eczema improved in six infants when their mothers avoided egg and cows'' milk and worsened again when these were reintroduced. Two infants suffered gastrointestinal reactions after maternal ingestion of egg and cows'' milk, one developing colitis. Maternal dietary exclusion seems to benefit some breast fed babies with eczema. 相似文献
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9.
The phylogeny of Greya Busck (Lepidoptera: Prodoxidae) was inferred from
nucleotide sequence variation across a 765-bp region in the cytochrome
oxidase I and II genes of the mitochondrial genome. Most parsimonious
relationships of 25 haplotypes from 16 Greya species and two outgroup
genera (Tetragma and Prodoxus) showed substantial congruence with the
species relationships indicated by morphological variation. Differences
between mitochondrial and morphological trees were found primarily in the
positions of two species, G. variabilis and G. pectinifera, and in the
branching order of the three major species groups in the genus. Conflicts
between the data sets were examined by comparing levels of homoplasy in
characters supporting alternative hypotheses. The phylogeny of Greya
species suggests that host-plant association at the family level and larval
feeding mode are conservative characters. Transition/transversion ratios
estimated by reconstruction of nucleotide substitutions on the phylogeny
had a range of 2.0-9.3, when different subsets of the phylogeny were used.
The decline of this ratio with the increase in maximum sequence divergence
among taxa indicates that transitions are masked by transversions along
deeper internodes or long branches of the phylogeny. Among transitions,
substitutions of A-->G and T-->C outnumbered their reciprocal
substitutions by 2-6 times, presumably because of the approximately 4:1
(77%) A+T-bias in nucleotide base composition. Of all transversions,
73%-80% were A<-->T substitutions, 85% of which occurred at third
positions of codons; these estimates did not decrease with an increase in
maximum sequence divergence of taxa included in the analysis. The high
frequency of A<-->T substitutions is either a reflection or an
explanation of the 92% A+T bias at third codon positions.
相似文献
10.
A new paleoenvironmental proxy, Eucampia Index, was used to trace the Late Pleistocene oscillations of winter ice extent at ODP Leg 119, Site 745B (59° 35.71 S and 85° 51.60 E) on the Kerguelen Plateau. The index is calculated as the ratio of winter terminal to intercalary valves of the diatom Eucampia antarctica sensu lato. During the early Brunhes the winter sea-ice edge was positioned south from Site 745. It started expanding northward, closer to the site location soon after 0.4 Ma and progressed in a manner of a several wide oscillations. For approximately the last 0.1 Ma the winter sea-ice edge oscillated less and retained similar range of oscillations. The ice edge oscillated in periods which correspond closely to that of Milankovitch oscillations of Earth obliquity, although the significance of individual periods appears to vary in time. 相似文献