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961.
Genetic diversity and differentiation of indica and japonica rice detected by RFLP analysis 总被引:4,自引:0,他引:4
Qifa Zhang M. A. Saghai Maroof T. Y. Lu B. Z. Shen 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1992,83(4):495-499
Summary Genetic diversity and differentiation in indica and japonica groups of the cultivated rice (Oryza sativa L.) were studied by assaying DNA restriction fragment length polymorphisms of 12 indica and 14 japonica rice lines digested with three restriction endonucleases. A total of 49 probes were selected to represent the entire RFLP map at intervals of 20–30 cM. It was shown that 95 of the 145 possible probe/enzyme combinations, involving 43 probes and all three enzymes, detected restriction fragment length variation, and the degree of polymorphism varied greatly from one probe/enzyme combination to another. These results demonstrate that indica rice is genetically more diverse than japonica type. Significant differentiation between the two rice groups was detected by 33 probes representing 11 of the 12 rice chromosomes. It was deduced that the processes leading to differentiation involved a combination of molecular events that include base substitutions and insertion/deletions. 相似文献
962.
Tomomasa Watanabe Yuka Sakai Shigeki Miyawaki Atsuko Shimizu Osamu Koiwai Kyoko Ohno 《Biochemical genetics》1991,29(7-8):325-335
The mouselpr gene, which is an autosomal recessive gene causing autoimmune disease with features of human systemic lupus erythematosus and eventually death from severe immune-complex glomerulonephritis, has been mapped on chromosome 19. To determine its exact chromosomal location, a three-point backcross was carried out by mating (MRL/MpJ-lpr/lpr × MOL-MIT)F1 × MRL/MpJ-lpr/lpr using the genesLy-44 (lymphocyte differentiation antigen-44) andTdt (terminal deoxynucleotidyl transferase) as markers. The following order of genes is proposed, with the distances between genes given in parentheses: centromere-Ly-44 (19.3 cM)-lpr (6.1 cM)-Tdt-telomere. TheLy-44
a
andTdt
a
alleles are found in all laboratory strains and in the wild Western European subspecies,domesticus andbrevirostris. In contrast, theLy-44
b
andTdt
b
alleles are found in some Asian subspecies, Chinese mice of wild origin,yamashinai andmolossinus. Furthermore the thirdTdt allele,Tdt
c
, is detected incastaneus.Some of the data in this study were previously presented at the 4th Mouse Gene Mapping Workshop, Annapolis, Maryland, in November 1990. 相似文献
963.
964.
Sequential Monte Carlo p-values 总被引:4,自引:0,他引:4
965.
M. Mazor M. Harel S. Levsky E. Dunkelblum 《Entomologia Experimentalis et Applicata》1991,60(2):167-172
Capillary gas chromatography indicated the presence of (Z)-7-dodecenyl alcohol and (Z)-7-dodecenyl acetate in the abdominal tip extracts of female Cornutiplusia circumflexa (L.) (Lepidoptera: Noctuidae: Plusiinae) moths. Gas chromatography combined with mass spectrometry and dimethyl disulfide derivatization confirmed the structure of these two principal pheromone components. In a flight-tunnel bioassay, a 5:1 blend of alcohol and acetate elicited the complete courtship sequence by males. The response was comparable to that evoked by a live virgin female, but males spent significantly longer time at calling females than at the synthetic source. The 5:1 blend was also attractive to male C. circumflexa in the field, as indicated by catches in traps baited with this mixture. (Z)-7-dodecenyl alcohol alone was slightly attractive whereas (Z)-7-dodecenyl acetate alone was completely inactive. C. circumflexa is the first reported Plusiinae species which utilizes (Z)-7-dodecenyl alcohol as the major pheromone component. 相似文献
966.
967.
Evaluation of nongenotoxic and genotoxic factors modulating the frequency of micronucleated erythrocytes in the peripheral blood of mice 总被引:3,自引:0,他引:3
The hematological micronucleus test is regarded as an indicator of the clastogenic effect of chemicals and acute cytogenetic damage. The test can be carried out in red blood cells of the bone marrow and of the spleen, as well as in peripheral erythrocytes. We have determined the precise background values of micronucleated red blood cells for the peripheral blood of BALB/c, DBA/2, and NMRI mice. Bleeding, phenylhydrazine-induced hemolysis, and splenectomy generated an increase of micronucleated erythrocytes in the peripheral blood of mice. Our data thus demonstrate that such factors should be taken into consideration when the micronucleus test is used for screening the genotoxic potential of chemicals. Furthermore, the micronucleus-inducing effect of cyclophosphamide was studied in normal and splenectomized mice and, in addition, a comparison of the sensitivity of the micronucleus test was carried out in peripheral blood and bone marrow after cyclophosphamide treatment. Our data demonstrate that the kinetics of micronucleus formation were similar in normal and in splenectomized mice in which the micronucleus levels had returned to normal. The comparison of micronucleus formation in bone marrow and peripheral blood after cyclophosphamide treatment revealed the generation of similar quantities of micronucleated red blood cells in both tissues. The physiological mechanisms of micronucleus formation and removal and the potential role of chemically induced spleen damage during this process are discussed; the usefulness of the peripheral micronucleus test as a simple, rapid, and animal-saving modification of the standard bone marrow test is evaluated.Abbreviations CP
cyclophosphamide
- MN
micronuclei
- MNCE
micronucleated normochromatic erythrocytes
- MNPCE
micronucleated polychromatic erythrocytes
- MNRBC
micronucleated red blood cells
- NCE
normochromatic erythrocytes
- PCE
polychromatic erythrocytes 相似文献
968.
Blaithin A. McMahon Jay L. Koyner Tessa Novick Steve Menez Robert A. Moran Bonnie E. Lonze 《Biomarkers》2018,23(1):61-69
Objectives and methods: The Furosemide Stress Test (FST) is a novel dynamic assessment of tubular function that has been shown in preliminary studies to predict patients who will progress to advanced stage acute kidney injury, including those who receive renal replacement therapy (RRT). The aim of this study is to investigate if the urinary response to a single intraoperative dose of intravenous furosemide predicts delayed graft function (DGF) in patients undergoing deceased donor kidney transplant.Results: On an adjusted multiple logistic regression, a single 100?mg dose of intraoperative furosemide after the anastomosis of the renal vessels (FST) predicted the need for RRT at 2 and 6?h post kidney transplantation (KT). Recipient urinary output was measured at 2 and 6?h post furosemide administration. In receiver-operating characteristic (ROC) analysis, the FST predicted DGF with an area-under-the curve of 0.85 at an optimal urinary output cut-off of <600 mls at 6?h with a sensitivity of and a specificity of 83% and 74%, respectively.Conclusions: The FST is a predictor of DGF post kidney transplant and has the potential to identify patients requiring RRT early after KT. 相似文献
969.
Jeremy W. Schroeder Ponlkrit Yeesin Lyle A. Simmons 《Critical reviews in biochemistry and molecular biology》2018,53(1):29-48
Mutations in an organism’s genome can arise spontaneously, that is, in the absence of exogenous stress and prior to selection. Mutations are often neutral or deleterious to individual fitness but can also provide genetic diversity driving evolution. Mutagenesis in bacteria contributes to the already serious and growing problem of antibiotic resistance. However, the negative impacts of spontaneous mutagenesis on human health are not limited to bacterial antibiotic resistance. Spontaneous mutations also underlie tumorigenesis and evolution of drug resistance. To better understand the causes of genetic change and how they may be manipulated in order to curb antibiotic resistance or the development of cancer, we must acquire a mechanistic understanding of the major sources of mutagenesis. Bacterial systems are particularly well-suited to studying mutagenesis because of their fast growth rate and the panoply of available experimental tools, but efforts to understand mutagenic mechanisms can be complicated by the experimental system employed. Here, we review our current understanding of mutagenic mechanisms in bacteria and describe the methods used to study mutagenesis in bacterial systems. 相似文献
970.
Prevalence of Helicobacter pylori among Alaskans: Factors associated with infection and comparison of urea breath test and anti‐Helicobacter pylori IgG antibodies 下载免费PDF全文
Karen M. Miernyk Lisa R. Bulkow Benjamin D. Gold Michael G. Bruce Debby H. Hurlburt Patricia M. Griffin David L. Swerdlow Kim Cook Thomas W. Hennessy Alan J. Parkinson 《Helicobacter》2018,23(3)