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81.
Storage proteins of the seeds (cotyledons) of the South-American speciesPhaseolus caracalla were compared by means of immunoelectrophoretic methods with other representatives of the genusPhaseolus. These proteins most resemble the proteins of the co-called tropical group (i.e. Ph. atropurpureus, Ph. geophilus, Ph. bracteatus, Ph. semierectus) and least the so-called American endemites (Ph. vulgaris, Ph. coccineus, Ph. acutifolius, Ph. lunatus), the main globulin of which is of a completely different specificity. The proteins ofPh. caracalla are less similar to the group of the so-called Asiatic species (Ph. aureus, Ph. calcaratus, Ph. angularis, Ph. aconitifolius, Ph. trilobus) including the analyzed representatives ofVigna sinensis; their main globulin is only partly similar to that ofPh. caracalla. Some considerations on the relationship ofPh. caracalla with the so-called tropical species is presented.  相似文献   
82.
Summary In an attempt to stimulate fetal cells in the maternal blood to mitotic division, peripheral blood lymphocytes were cultured from ten primiparous women and six multiparous women. In the case of the ten primiparous women, PWM was used to stimulate lymphocytes in 3- and 7-day cultures made at the 16th, 20th, 24th, and 28th week of gestation. Altogether, 10565 mitoses were analyzed after quinacrine staining of cells from five mothers who each subsequently gave birth to a male infant, and not a single XY mitosis was found.In the case of the multiparous women, lymphocyte cultures, with PHA or LPS as mitogen and MLC, were initiated between the 13th and 20th week of pregnancy. Four of the mothers were pregnant with a male child, and two with a female child. From cultures of each of the four mothers expecting a boy, a total of 9721 mitoses were analyzed after quinacrine staining, and not a single XY mitosis was found. However, one XY cell was found in the culture from one of the two women who delivered a girl. The XY mitosis probably originated from a pregnancy 8 months earlier which terminated in a male infant.In an attempt to culture and obtain good chromosome preparations from small numbers of cells, it was shown that a good mitotic response and good chromosome preparations could be obtained from as few as 6000 lymphocytes.  相似文献   
83.
Summary Spontaneous mutants (146) of Escherichia coli K-12 were selected that were resistant to inhibition of growth by 1.2 mM L-valine (Valr). The Valr isolates, containing acetohydroxy acid synthase resistant to feedback inhibition by L-valine (AHASr), were classed according to cotransduction of the mutation with leu. Several mutations resulting in an AHASr phenotype were found to be cotransducible with glyA. However, no mutations causing a Valr phenotype were linked to ilv. AHAS activity was more closely examined in representatives of three classes of mutants with Valr linked to leu, labeled ilv-660, ilv-661, and ilv-662. The ilvE503 allele in E. coli K-12, known to cause a two- to three-fold derepression of AHAS, was found to affect regulation of synthesis of both valine-sensitive AHAS (AHASs) and AHASr in the mutants containing ilv-660 and ilv-661, whereas it affected repression of AHASs, only, in the mutant containing ilv-662. Further, both AHASs and AHASr in the ilv-661 mutant were repressed by valine, whereas valine did not repress AHASr synthesis in the strain carrying ilv-660 and only partially repressed AHASr in the strain carrying ilv-662. Unexpectedly, AHASr synthesis in strains carrying ilv-660 or ilv-662 was repressible by leucine. The ilv-660 locus appears to be similar in position to ilvH and encodes a product that confers valine-sensitivity upon AHAS activity in the wild-type E. coli K-12. The ilv-660 and ilv-662 loci may normally encode products that influence both the feedback sensitivity of AHAS and control of AHAS biosynthesis.  相似文献   
84.
Wood samples, infested by fungi during storage, were shown to contain, besides the known 5-methyl-mellein, additional (3R)-8-hydroxy-3-methyl-3,4-dihydroisocoumarins substituted by 7-methyl, 5-formyl, 5-carboxy, 5-hydroxy, 5-methoxy, 6-methoxy-5-methyl and 6,7-dimethoxy-5-methyl groups, as well as 6-formyl-7-hydroxy-5-methoxy-4-methylphthalide. Several 2-methylchromanones were synthesized in order to show that this class of compounds can be distinguished from 3-methyl-3,4-dihydroisocoumarins by MS.  相似文献   
85.
Eva Diel  Hans-Jürgen Stan 《Planta》1978,142(3):321-328
A chromatographic procedure for the purification of two lipoxygenase isoenzymes (linoleate: O2 oxidoreductase, EC 1.13.11.12.) from soybean is described. The procedure for the purification of isoenzyme L-1 includes optimalized extraction, ammonium sulfate fractionation, heat treatment and gradient elution from a CM-Sephadex C-50 column. The purification of L-2 includes ammonium sulfate fractionation, gelfiltration on Sephadex G-150 and gradient elution from a DEAE-cellulose column. Both isoenzymes L-1 and L-2 appear homogeneous after Disc-PAGE. The isoelectric points are 5.6 for L-1 and 5.8 for L-2. Molecular weights are estimated as 100,000 for L-1 as well as L-2 applying three different methods. Both isoenzymes contain 0.9 mol iron per mol protien. The estimated turn over numbers are 8,200 mol linoleate per mol enzyme and min for L-1 and 3,100 for L-2. Amino acid compositions determined after acid hydrolysis show marked differences between L-1 and L-2, particularly with respect to the amino acids Lys, Phe, Ser, Gly and Leu. L-1 posesses a total of 9 cysteine molecules, 6 of which are present as disulfide bonds. L-2 posesses a total of 8 cysteine molecules with only one disulfide bond.These results have been presented in part at the 13th ISF Congress in Marseille on 2nd September 1976  相似文献   
86.
The maximum activities of 6-phosphofructokinase and oxoglutarate dehydrogenase in muscle provide quantitative indices of the maximum capacities of anaerobic glycolysis and the Krebs cycle (i.e. the aerobic capacity) respectively. These activities were measured in red, white, and cardiac muscle of birds and the rat. The activities in the white pectoral muscle of the domestic fowl suggest that the Krebs cycle plus electron transfer could provide only about 1% of the rate of ATP production provided by anaerobic glycolysis whereas in pigeon pectoral muscle the predicted maximal rates from the two processes are similar. In contrast to domestic-fowl pectoral muscle, the white rat muscle, epitrochlearis, contains a significant activity of oxoglutarate dehydrogenase, which indicates that the Krebs cycle could provide about 12% of the maximum rate of ATP formation. This may be explained by a higher proportion of type-I and -IIA fibres in the rat muscle compared to the avian muscle. In the aerobic muscles of the rat the maximum activities of carnitine palmitoyl transferase indicate that fatty-acid oxidation could provide a high rate of ATP formation.  相似文献   
87.
Callus was induced from mature leaf lamina, petiole, stem, and main and branch root of Panax ginseng and maintained under different nutrient and light conditions. Heterogenous callus cultures differentiated organoids and/or embryoids. Embryoids that arose from callus cultures of leaf origin germinated into shoots. The occurrence of the early stages of different regenerated structures was proved on histological level.  相似文献   
88.
A new homeobox-leucine zipper gene from Arabidopsis thaliana   总被引:3,自引:0,他引:3  
We have isolated a homeobox-containing gene from Arabidopsis thaliana using a degenerate oligonucleotide probe corresponding to the most conserved region of the homeodomain. This strategy has been used previously to isolate homeobox-containing genes from Caenorhabditis, and recently from A. thaliana. The Arabidopsis genes have an unusual structure in that they have a leucine zipper motif adjacent to the carboxy terminal region of the homeo domain, a feature not found in homeobox-containing genes isolated from animals. We report the isolation and primary structure of a new member of this Arabidopsis homeobox-leucine zipper gene family. This new member has the homeodomain and leucine-zipper motif similar to the two genes previously identified, but differs from these genes in the part corresponding to the carboxy terminus of the polypeptide, as well as in size and isoelectric point of the protein.  相似文献   
89.
Summary T-cell cultures derived from the blood of 14 patients with solid tumors were propagated with T-cell growth factor (TCGF). The cultures were initiated from lymphocytes exposed to autologous tumor-biopsy cells. TCGF was added either immediately or 3–10 days later. In the former culture type the cell yield on day 7 was considerably higher. The cytotoxic potential of the cultured cells was assayed on two occasions, between days 7 and 10 and between weeks 5 and 8. Cells of all but two cultures had the potential to lyse autologous tumor-biopsy cells.On the population level, cytotoxicity was specific for autologous tumor in those cultures that were driven to growth with TCGF after the 3rd day. These lymphocytes did not lyse allogeneic tumor-biopsy cells. In contrast, all five cultures initiated in the presence of TCGF exhibited a broader cytotoxic potential, i.e., in addition to the stimulator autologous-tumor cells, they also lysed other targets. Another difference between the two culture types was their behavior toward K562. Tested on the 7th day they all lysed K562; however, this function declined in strength or disappeared later in the cultures exposed to TCGF after the 3rd day.Reexposure of the lymphocytes to autologous tumor-biopsy cells after 2 weeks of culture period, but not on the 7th day, induced DNA synthesis. This secondary response was specific inasmuch as allogeneic tumor cells had little or no effect.One of the autotumor restimulated cultures was tested for cytotoxic potential. It increased against the autologous but not against other tumors or K562 cells.  相似文献   
90.
Karyotypically XY individuals of the C57BL/6J-YPOS mouse stock develop as females or hermaphrodites, but never as normal males. The aberrant sexual development results from the interaction of the C57BL/6J genetic background with the M. poschiavinus-derived Y chromosome. XY females from this stock were assayed for H-Y antigen. By the criteria of skin-grafting, the cell-mediated lympholysis test, and the popliteal lymph node assay, these XY females are antigenically indistinguishable from normal C57BL/6 males. Implications for the hypothesis that H-Y antigen induces formation of the mammalian testis are discussed.  相似文献   
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