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261.
The effect of collection technique, anticoagulant, pH, glucose, and temperature on in vitro granulocyte function were studied after 24 hr of storage in the liquid state. Collection by CL did not adversely affect granulocyte function, however, cells collected by FL had accelerated loss of bactericidal activity and chemotactic response. Citrate anticoagulants provided better maintenance of bacteridical activity, NBT reduction, and chemotactic response than heparin, EDTA, and ion-exchange anticoagulants. Chemiluminescence was well maintained when the initial pH of the preservative solution (CPD plasma) was between 6.5 and 8.0 but maintenance of chemotaxis required pH of 7.0–7.5. Glucose concentrations of 80–1000 mg/dl provided adequate maintenance of chemiluminescence and chemotaxis. Bacterial killing was well maintained by storage at either 1–6 or 20–24 °C. Storage at 1–6 °C caused decreased chemotaxis, decreased ability of granulocytes to adhere and spread on a foreign surface, and a decreased intravascular recovery and shortened half-life after transfusion. Although short-term liquid storage may be practical, at present, granulocytes should be transfused as soon as possible after collection. 相似文献
262.
Barbara R. Hough-Evans Marcelo Jacobs-Lorena Michael R. Cummings Roy J. Britten Eric H. Davidson 《Genetics》1980,95(1):81-94
Comparative measurements are presented of the sequence complexity of the RNA stored in the eggs of two dipteran flies, Musca domestica and Drosophila melanogaster. The genome of Musca is about five times the size of the Drosophila genome and contains about 3.6 times as much single-copy sequence. As shown earlier, the interspersion of repetitive and single-copy sequence is of the short-period form in Musca, and is of the long-period form in Drosophila. The egg RNA complexities were determined by hybridization of excess RNA with radioactively labeled single-copy DNA. Complexity is expressed as the length (in nucleotides) of diverse single-copy sequence represented in the RNA. The complexity of the RNA of the Musca egg is about 2.4 x 107 nucleotides, and that of the Drosophila egg is about 1.2 x 107 nucleotides. The RNA of the Musca egg is similar to or very slightly lower in complexity than that of other egg RNAs, e.g., those of Xenopus and sea urchin. Compared to all previously measured egg RNAs, Drosophila egg RNA is low in sequence complexity. 相似文献
263.
Detection of the Viral Sarcoma Gene Product in Cells Infected with Various Strains of Avian Sarcoma Virus and of a Related Protein in Uninfected Chicken Cells 下载免费PDF全文
Joan S. Brugge Marc S. Collett Aleem Siddiqui Barbara Marczynska F. Deinhardt R. L. Erikson 《Journal of virology》1979,29(3):1196-1203
Genetic analyses have defined a single gene (src) as that portion of the avian sarcoma virus (ASV) genome which encodes the protein directly responsible for ASV-induced neoplastic transformation. We have recently identified the polypeptide product of the src gene of the Schmidt-Ruppin (SR) strain of ASV, a 60,000-dalton phosphoprotein designated pp60(src), and have further determined that pp60(src) acts as a protein kinase. Essential to the identification and characterization of the pp60(src) protein of SR-ASV was the use of serum (TBR serum) from rabbits bearing SR-ASV-induced tumors. TBR serum was, however, strain specific, recognizing pp60(src) from SR-ASV-transformed cells only. We report here that sera from marmosets bearing tumors induced by the Bryan or SR strains of ASV (TBM sera) contain antibody which precipitates the transforming gene product from cells transformed by the SR, Bryan, Prague, or Bratislava strains of ASV. In contrast, rabbits bearing tumors induced by either the Bratislava or Bryan strains of ASV, or hamsters with SR-ASV-induced tumors did not produce antibody to pp60(src) from any strain of ASV. The 60,000-dalton polypeptides immunoprecipitated with TBM serum from cells transformed by each of the above virus strains are phosphoproteins. One-dimensional peptide mapping by limited proteolysis revealed that the pp60(src) proteins are structurally very similar, but not identical. Furthermore, all of the viral pp60(src) proteins have an associated phosphotransferase activity. In addition to detecting the viral src proteins, TBM serum was able to immunoprecipitate an antigenically related protein from normal uninfected avian cells. 相似文献
264.
A M Morselli E Roda A Roda C Sama R Aldini G Mazzella D Festi F Bazzoli E Sarti L Barbara 《Bollettino della Società italiana di biologia sperimentale》1979,55(15):1527-1533
A multicompartmental model was applied to the study of the plasmatic and biliary kinetics of the 14C-Cholic acid intravenously injected into a baboon in normal and cholestatic condition. For the evaluation of transfer rates FORTAN IV procedures were used, utilizing Powell method. The degree of fitting was: in normal condition in serum 7% for free and 35% for conjugated Cholic acid, while in bile 5% and 4% respectively; in serum in cholestatic condition 7% for free and 12% for conjugates. The high degree of fitting and reliable estimation of transfer rates suggest that the multicompartmental model applied represents most likely the physio-pathological conditions studied. 相似文献
265.
Head movements of different species of walking beetles elicited by rotating stripe patterns have been investigated. They are of the usual type in contrast to an inverted nystagmus reported forTenebrio molitor in similar experimental situations. Reexamination of theTenebrio records revealed that the sign of the stimulus was interchanged by a mistake while plotting the results. Thus, the head nystagmus inTenebrio is also of the usual type, consisting of a smooth pursuit head movement followed by a faster returning phase. 相似文献
266.
267.
One-GHz microwave (MW) irradiation at a power density of 5 mW/cm2 was combined with methotrexate (MTX) in an attempt to treat more effectively central nervous system (CNS) L1210 leukemia in DBA/2J mice. When mice with CNS leukemia were treated with the combination of MW and MTX, there was no improvement in survival compared with a group of animals treated with MTX alone; however, the group that received MTX before the MW exposure had a significantly reduced survival time compared with the group treated with MTX alone or with the group to which MTX was administered after MW. 相似文献
268.
269.
270.
Peter Albersheim Arthur R. Ayers Barbara S. Valent Jürgen Ebel Michael Hahn Jack Wolpert Russell Carlson 《Journal of cellular biochemistry》1977,6(4):599-616
Plants are resistant to almost all of the microorganisms with which they come in contact. In response to invasion by a fungus, bacterium, or a virus, many plants produce low molecular weight compounds, phytoalexins, which inhibit the growth of microorganisms. Phytoalexins are produced whether or not the invading microorganism is a pathogen. The production of phytoalexins appears to be a widespread mechanism by which plants attempt to defend themselves against pests. Molecules of microbial origin which trigger phytoalexin accumulation in plants are called elicitors. Structural polysaccharides from the mycelial walls of several fungi elicit phytoalexin accumlation in plants. Approximately 10 ng of the polysaccharide elicits the accumulation in plants of more than sufficient amounts of phytoalexin to stop the growth of microorganisms in vitro. The best characterized elicitors have been demonstrated to be β-1,3-glucans with branches to the 6 position of some of the glucosyl residues. Oligosaccharides, produced by partial acid hydrolysis of the mycelial wall glucans, are exceptionally active elicitors. The smallest oligosaccharide which is still an effective elicitor is composed of about 8 sugar residues. Bacteria also elicit phytoalexin accumulation in plants, but the Rhizobium symbionts of legumes presumably have a mechanism which allows them to avoid either eliciting phytoalexin accumulation or the effects of the phytoalexins if they are accumulated. The lectins of legumes bind to the lipopolysaccharides of their symbiont, but not of their non-symbiont, Rhizobium. It is not known whether the lectin-lipopolysaccharide interaction is involved with the establishment of symbiosis. However, evidence will be presented that suggests that lectins are, in fact, enzymes capable of modifying the structurs of the lipopolysaccharides of their symbiont, but not of their non-symbiont, Rhizobium. It will also be shown that the lipopolysaccharides isolated from different Rhizobium species and from different strains of individual Rhizobium species have different sugar compositions. Thus, the different strains of a single Rhizobium species are as different from one another as the different species of Salmonella and other gram-negative bacteria. This conclusion is substantiated by experiments demonstrating that antibodies to the lipopolysaccharide from a single Rhizobium strain can differentiate that strain from other strains of the same species as well as from other Rhizobium species. The role in symbiosis of the strain-specific O-antigens is unknown. 相似文献