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1.
The computer program HYLAS generates from a standard DNA lettersequence a three-dimensional space curve (H curve) which embodiesthe entire information content of the original nucleotide sequence.The program can display H curves either as two-dimensional (frontand side view) projections or as stereo-pair images. The curvescan be marked at specific nucleotide locations, annotated, rotatedfor observation from any viewing angle, and manipulated forconvenient side-by-side comparisons. Unlike the cumbersome lettersequences, H curves can be drastically condensed in size withoutlosing their ability to reflect the global nucleotide-distributionpattern of the entire DNA sequence. Often, biologically importantloci can be visually identified on the H curves. HYLAS is writtenin FORTRAN with separate mainframe (IBM- VM/CMS) and microcomputer(MS-DOS) versions. It uses the Tektronix-TCS library of graphicsubroutines. Received on October 24, 1988; accepted on July 15, 1989  相似文献   
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Pregnant rats were treated on day 11 of pregnancy with 0.62, 1.25, 2.5 or 5.0 mg of isoxazole per 100 g of body weight (bw) (Experiment I) or with 2.5 mg of isoxazole per 100 g of bw (Experiment II). In Experiment I animals were anaesthetized with pentobarbital at 48 hr. In experiment II animals were similarly anaesthetized at 0, 12, 24, or 48 hr following administration of isoxazole. Blood was collected separately from the ovary or from the uterus via a thin cannula which was inserted into the utero-ovarian vein. Blood was also collected from the vena cava inferior. The concentrations of progesterone (P), 17 beta-oestradiol (E2), and corticosterone were measured in blood samples by RIA. All of the animals exhibited reduced rates of ovarian venous blood flow and rates of P secretion when pregnancy was terminated by isoxazole (2.5 mg/100 g bw or greater). The concentration of P was found to be correspondingly reduced by 90% in ovarian venous blood and by 50% in peripheral blood, relative to the controls. After isoxazole had been administered, the rate of P secretion and also the concentration of P in peripheral blood continued to decrease rapidly and to remain at low levels for at least 48 hr. By contrast, the concentration of corticosterone in peripheral blood decreased during the first 12 hr but then it returned to the control levels by 48 hr. The ovarian secretion rate of E2 and the concentration of E2 in peripheral blood remained unchanged during the same 48 hr period.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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To elucidate the position of the peptide bond in glutamyl-taurine this dipeptide was extracted from calf brain synaptic vesicles and subjected to paper electrophoresis. It was analyzed further in an automatic amino acid analyzer prior and subsequent to acid hydrolysis. Both alpha- and gamma-forms were found to be present in approximately equal amounts.  相似文献   
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At the international tournament in 1982 in Moscow and Tashkent 254 leading footballers of the world from 10 national young combined teams have been undergone an anthropological examination. In all the persons examined main total body dimensions, fat mass in per cent and somatotype after B. Hint and J. Carter have been determined. The leading footballers of the world are of more than middle height and tall, the body mass is proportional to its length, the fat mass values are not great. Their specific somatotype is well-balanced mesomorphic and ectomesomorphic types. The average somatotype of the footballers examined can be presented as 1.7-5.6-2.6. The data obtained can be used when selecting and complexing national combined teams with perspective sportsmen.  相似文献   
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The omega-conotoxins from the venom of fish-hunting cone snails are probably the most useful of presently available ligands for neuronal Ca channels from vertebrates. Two of these peptide toxins, omega-conotoxins MVIIA and MVIIB from the venom of Conus magus, were purified. The amino acid sequences show significant differences from omega-conotoxins from Conus geographus. Total synthesis of omega-conotoxin MVIIA was achieved, and biologically active radiolabeled toxin was produced by iodination. Although omega-conotoxins from C. geographus (GVIA) and C. magus (MVIIA) appear to compete for the same sites in mammalian brain, in amphibian brain the high-affinity binding of omega-conotoxin MVIIA has narrower specificity. In this system, it is demonstrated that a combination of two omega-conotoxins can be used for biochemically defining receptor subtypes and suggested that these correspond to subtypes of neuronal Ca2+ channels.  相似文献   
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A main problem in the vegetative propagation of ornamental plants in vitro is the epigenetic instability of cells removed from their organized environment. With calluses of leaf explants of Kalanchoe blossfeldiana Poelln., cv. Yucatan, the role of plant growth regulators (PGRs) in the occurrence of fasciation was studied.In various combinations of auxins and cytokinins, the auxin 2,4-D (2,4-dichlorophenoxyacetic acid) gave only deformed, inseparable shoot primordia. The most rapid callus induction with regeneration of well-developed sprouts was obtained with the natural IAA (indoleacetic acid) and Z (zeatin).As a first symptom of fasciation, aberration in decussate phyllotaxis can be observed. At increasing concentrations of IAA + Z, this symptom gradually decreased but fasciation proper increased. The optimum concentration was at 1 M for both PGRs. Reduction of exposure to the PGRs from six to three weeks reduced the epigenetic instability.  相似文献   
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