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1.
Phenylacetic, 3-phenylpropionic, -hydroxyphenylacetic and 3 (-hydroxyphenyl) propionic acids together with the series of C2 to C6 saturated fatty acids previously reported in the anal sac secretion of the red fox () are identified as constituents of the anal sac secretion of the lion (Panthera leo). All these compounds are also observed in the anal sac secretion of the red fox using gas chromatography. The aerobic microflora of red fox and domestic dog () anal sac secretion samples invariably consisted predominantly of and . The hypothesis that the secretion volatiles so far identified may be microbiologically produced is examined. 相似文献
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Two hundred fifty-one ovine embryos were frozen in different levels of glycerol (1.0, 1.4, 2.0 or 2.8M) and thawed into one of four sucrose levels (0, 0.25, 1.0 or 2.0M) to determine the optimal glycerol-sucrose combination for one-step, in-straw thawing. Sucrose was toxic at low glycerol levels and mandatory at high levels. The 1.0M sucrose level with either 1.4 or 2.0M glycerol was optimal for one-step cryoprotectant removal. 相似文献
4.
Resistance to the cytolytic action of lymphotoxin and tumor necrosis factor coincides with the presence of gap junctions uniting target cells 总被引:3,自引:0,他引:3
W H Fletcher W W Shiu T A Ishida D L Haviland C F Ware 《Journal of immunology (Baltimore, Md. : 1950)》1987,139(3):956-962
The resistance of target cells to the cytolytic action of lymphotoxin (LT) and recombinant tumor necrosis factor (rTNF) has been investigated by using clonally derived cell lines with defined gap junction-mediated, intercellular communication properties. Gap junction-competent Chinese hamster ovary cells are normally insensitive to the action of LT/TNF. However, treatment with 12-o-tetradecanoylphorbol-13-acetate, which promotes the loss of gap junctions, or culturing at low cell density to reduce intercellular contacts, significantly increased their sensitivity to LT/TNF. The LT/TNF-sensitive murine CL-1D and L929 cell lines, which in normal culture conditions are unable to form gap junctions, were not changed in their susceptibility to LT/TNF after treatment with phorbol ester or low culture density. However, the formation of gap junctions by CL-1D can be promoted by treatment with 8-bromo-cyclic adenosine monophosphate (1 mM), and this treatment completely suppressed the ability of LT and rTNF to kill CL-1D. Additionally, the LA25-normal rat kidney cell line, which is infected with a temperature-sensitive mutant of Rous sarcoma virus (LA25), is gap junction-competent and resistant to the effects of LT at the restrictive temperature (39 degrees C). However, when shifted to the permissive temperature (33 degrees C), LA25-normal rat kidney cells express the pp60v-src viral gene product, lose their ability to form gap junctions, and become sensitive to the lytic activity of LT. The results demonstrate that the expression of the retroviral pp60v-src, a tyrosine protein kinase, is sufficient to render cells susceptible to the lytic effects of LT and rTNF. Collectively, these experiments demonstrate a strong correlation between the resistance of target cells to the action of LT/TNF and their ability to cooperate metabolically through gap junctions. The results do not completely exclude the possibility that other mechanisms, such as LT receptor modulation, are also occurring under these experimental conditions. These data also suggest that a possible physiologic function of the stable cytotoxic lymphokines is to induce cytolysis/cytostasis of cells that have lost gap junctional contact, such as those in the process of mitosis or metastasis that have separated from the main tissue mass. 相似文献
5.
Nucleotide sequence of a cDNA for a member of the human 90-kDa heat-shock protein family 总被引:20,自引:0,他引:20
This paper describes the isolation and sequence of a human cDNA homologous to a class of proteins commonly referred to as 90-kDa heat-shock proteins. The complete nucleotide sequence of 2563 bp and the deduced amino acid sequence are presented. A single long open reading frame encodes a protein of 83,303 Da, the amino acid composition of which correlates well with that determined for the human 90-kDa heat-shock or 'stress' protein [Welch, W.J. and Feramisco, J.R., J. Biol. Chem. 257 (1982) 14949-14959]. Moreover, sequence analysis of this gene reveals extensive homology with the Drosophila 83-kDa and yeast 90-kDa heat-shock proteins. A comparison of the translated product of the human cDNA to the published yeast 90-kDa heat-shock protein reveals more than 60% homology at both the nucleotide and amino acid levels. Several regions of 50 aa or more show greater than 90% identity. This cDNA also hybridizes with an RNA species which increases upon heat shock of HeLa cells. 相似文献
6.
The malmö polymorphism of coagulation factor IX, an immunologic polymorphism due to dimorphism of residue 148 that is in linkage disequilibrium with two other F.IX polymorphisms 下载免费PDF全文
John B. Graham Dennis B. Lubahn Susan T. Lord Julie Kirshtein Inga Marie Nilsson Anders Wallmark Rolf Ljung L. D. Frazier Jerry L. Ware Shu Wah Lin Darrell W. Stafford John Bosco 《American journal of human genetics》1988,42(4):573-580
A mouse monoclonal antibody (MAB 9.9) to coagulation factor IX (F.IX) detects a polymorphism in the plasma of normal people. Its epitope has been narrowed down to <6 amino acids in the activation peptide of the X-linked F.IX protein. The activation peptide contains a dimorphism—Thr:Ala—at position 148 of the protein. Using synthetic oligonucleotides, we have demonstrated that (1) the F.IX which reacts with 9.9 has Thr at position 148 and (2) that which does not has Ala. Positive reactors (148thr) are designated Malmö A, and negative reactors (148ala) are designated Malmö B. The plasma levels of AA women are indistinguishable from those of A men, and both B men and BB women are null against MAB 9.9. The plasma level of Malmö A in AB women is approximately half that of AA women, and “lyonization” is clearly operating in the heterozygotes. The dimorphism is in strong linkage disequilibrium with two other intragenic RFLPs, TaqI and XmnI. Furthermore, intragenic crossing-over—including double crossing-over—appears to have occurred between the three sites. Seven of the eight possible haplotypes have been identified, five in men and two others in women. The immunoassay that identifies ~50% of the AB women in the pool of Malmö A females with 95% confidence identifies men unambiguously as A or B. The assay would be very useful for population-genetic studies of the Malmö epitope if the studies were limited to men. 相似文献
7.
Z. Dave Sharp Anna Meriwether Jerry Ware M. Donald Cave 《Biochemical genetics》1986,24(11-12):911-923
An analysis of a 29-kilobase nontranscribed spacer fragment in the ribosomal DNA (rDNA) of the house cricket, Acheta domesticus, revealed a highly repetitious structure. A total of eight EcoRI repeats of three different size classes measuring 259, 420, and 508 base pairs (bp) was mapped to a region 2 kilobases (kb) from the 18 S coding region. The repeats were oriented in a nonrandom manner and had sequences homologous to DNA located immediately adjacent to the repetitive array. DNA sequence analysis showed that the repetitive region was composed of smaller direct repeats 66, 67, and 383 bp in length. There was minor length heterogeneity of the chromosomal restriction fragments containing the entire array, indicating that a variable number of EcoRI repeats is a minor contributor to the total repeat-unit length heterogeneity. Immediately upstream from the EcoRI array there is a 17-kb region composed of 50 to 60 subrepeat elements recognized by a variety of restriction endonucleases. A subcloned SmaI repeat from the array was not homologous to any other part of the rDNA repeat unit or other chromosomal DNA. There was little length heterogeneity in restriction fragments containing the chromosomal 17-kb repetitions region. Immediately upstream from the 17-Kb region there is a 4.1-kb segment with sequences homologous to the EcoRI repeats. 相似文献
8.
K. Bondari K. W. Washburn G. O. Ware 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1985,71(2):153-158
Summary Two experiments were conducted simultaneously to determine (1) if fast-growing fingerlings of channel catfish, Ictalurus punctatus, could be identified by simple visual selection of body size and (2) if initial size advantages influenced subsequent growth and carcass traits of divergently selected channel catfish. Exp. 1 included large (L), medium (M), and small (S) fingerling sizes from each of the control (C), selected upward (+) and selected downward (–) lines for body weight. Exp. 2 included all fmgerlings of the same size (25±5 g) from the 3 lines. Catfish from the L size-class, within each full-sib family in each line, were consistently heavier and longer than M and S size-classes throughout the 53-week experimental period. Fingerlings from the M size-class were also superior in growth to those from the S size-class. Catfish from the + line exceeded those from the C and –lines in body weight and total length at the conclusion of Exp. 1 but not in Exp. 2. This was attributed to the selection of equal size fmgerlings in Exp. 2 which may have excluded fingerlings with the best growth potential from the + body weight line. Results of the two experiments combined indicated that one generation of divergent selection has created genetic differences among lines of channel catfish.Supported by State and Hatch funds allocated to the Georgia Agricultural Experiment Station 相似文献
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Joy L. Ware Andrew P. Lieberman Karen S. Webb 《Cancer immunology, immunotherapy : CII》1986,21(1):58-62
Summary The human prostate tumor subline 1-LN-PC-3-1A (1-LN) is reproducibly metastatic in adult athymic nude mice. Cells surviving a brief in vitro exposure to ethyl methanesulfonate (EMS) exhibited a profound decrease in capacity for experimental lung metastasis in nude mice. Thirty days after EMS treatment, 1×106 uncloned EMS-treated 1-LN cells (1-LN-EMS-10) were injected IV into groups of 6 to 8-week-old male athymic nude mice (BALB/cAnBOM). A median of 8.5 colonies/lung was observed among 20 1-LN-EMS-10-injected mice, which was significantly different from the median of 51 colonies/lung produced among 14 1-LN-injected mice (P=0.0002). This altered phenotype remained stable during 150 days of continuous culture. However, the 1-LN-EMS-10 cells were tumorigenic in 10/10 nude mice injected SC. Single lung tumor colonies recovered from 1-LN-EMS-10-injected mice and reinjected IV into nude mice produced medians of 32–63 colonies/lung. The altered metastatic phenotype resulting from treatment of 1-LN with EMS was reversed by exposure to a noncytotoxic dose of 5-azacytidine, but unaffected by a second exposure to EMS. Collectively these data demonstrate that the metastatic phenotype of these human tumor cells in athymic nude mice can be heritably altered by in vitro exposure to EMS and 5-azacytidine. Analysis of the mechanisms underlying these phenotypic changes may provide insight into parts of the complex process of tumor cell evolution. 相似文献