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31.
T. C. Hsu Edward J. Shillitoe Lorraine M. Cherry Qi Lin Stimson P. Schantz Cynthia Furlong 《In vitro cellular & developmental biology. Plant》1990,26(1):80-84
Summary Forty lymphoblastoid (lymphoid) lines were established from 42 volunteer blood donors, including healthy individuals and patients
with head and neck carcinomas. Each peripheral blood sample was split into two portions, one for the establishment of a lymphoid
line and the other for short-term culture, which was used to estimate bleomycin sensitivity by cytogenetic procedures. Twenty
lymphoid lines were selected at random to compare bleomycin sensitivity with data obtained from short-term lymphocyte cultures.
In each set, bleomycin sensitivity of lymphoid cells was similar to that of the lymphocytes. The lymphoid lines, which can
be propagated for an unlimited supply of relatively homogeneous cellular material, will be useful for a variety of future
investigations.
This investigation was supported by grants from the John S. Dunn Foundation, Houston, TX, the Esther Knispel Fund administered
by The University of Texas M. D. Anderson Cancer Center, Houston, TX, and Department of Health and Human Services PHS grant
DE 07007. 相似文献
32.
五种野生稻叶绿体DNA多态性研究 总被引:7,自引:0,他引:7
对野生稻 5个种的18个材料的叶绿体DNA(cpDNA)进行了EcoRI的RFLP分析。
结果显示,共有10种酶切模式,不同种野生稻的cpDNA的RFLP类型都不同,而且在其中一些
种内也有变化,尤以O.rufipogon的种内多态性最为显著,并主要与地理来源有关。本研究还在O.punctata的材料中发现一种以往的分析都不曾描述过的多态性模式。通过对结果的分析,探讨了不同种类野生稻的叶绿体基因组之间以及它们与核基因组之间的进化关系。
Abstract:The polymorphisms of chloroplast DNA from 18 materials of 5 wild rice species were investigated using RFLP analysis.10 restriction patterns were obtained from the analysis of these materials.Different species had different of its RFLP patterns chloroplast DNA,and the polymorphisms existed even with species,especially in O.rufipogon varieties of different geographical origins.In O.punctata a new type of rice chloroplast DNA restriction pattern was discovered which had not been reported before.According to the results obtained,the evolutionary relationships among chlorplast genomes,and between chloroplast and nuclear genomes in different wild rice are discussed. 相似文献
33.
34.
R. Kapila M. S. Negi P. This M. Delseny P. S. Srivastava M. Lakshmikumaran 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1996,93(7):1123-1129
The 459-bp HindIII (pBN-4) and the 1732-bp Eco RI (pBNE8) fragments from the Brassica nigra genome were cloned and shown to be members of a dispersed repeat family. Of the three major diploid Brassica species, the repeat pBN-4 was found to be highly specific for the B. nigra genome. The family also hybridized to Sinapis arvensis showing that B. nigra had a closer relationship with the S. arvensis genome than with B. oleracea or B. campestris. The clone pBNE8 showed homology to a number of tRNA species indicating that this family of repeats may have originated from a tRNA sequence. The species-specific 459-bp repeat pBN-4 was localized on the B. nigra chromosomes using monosomic addition lines. In addition to the localization of pBN-4, the chromosomal distribution of two other species-specific repeats, pBN34 and pBNBH35 (reported earlier), was studied. The dispersed repeats pBN-4 and pBNBH35 were found to be present on all of the chromosomes, whereas the tandem repeat pBN34 was localized on two chromosomes. 相似文献
35.
Y. -C. Yang N. A. Tuleen G. E. Hart 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1996,92(5):591-598
Analyses of RFLPs, isozymes, morphological markers and chromosome pairing were used to isolate 12 Triticum aestivum cv Chinese Spring (genomes A, B, and D)-T. peregrinum (genomes Sv and Uv) disomic chromosome addition lines. The evidence obtained indicates that each of the 12 lines contains an intact pair of T. peregrinum chromosomes. One monosomic addition line, believed to contain an intact 6Sv chromosome, was also isolated. A CS-7Uv chromosome addition line was not obtained. Syntenic relationships in common with the standard Triticeae arrangement were found for five of the seven Sv genome chromosomes. The exceptions were 4Sv and 7Sv. A reciprocal translocation exists between 4S1 and 7S1 in T. longissimum and evidence was obtained that the same translocation exists in T. peregrinum. In contrast, evidence for syntenic relationships in common with the standard Triticeae arrangements were found for only one Uv chromosome of T. peregrinum.; namely, chromosome 2Uv. All other Uv genome chromosomes are involved in at least one translocation, and the same translocations were found in the U genome of T. umbellulatum. Evidence was also obtained indicating that the centromeric regions of 4U and 4Uv are homoeologous to the centromeric regions of Triticeae homoeologous group-6 chromosomes, that the centromeric regions of 6U and 6Uv are homoeologous to the centromeric regions of group-4 chromosomes, and that 4U and 4Uv are more closely related overall to Triticeae homoeologous group-6 chromosomes than they are to group-4 chromosomes. 相似文献
36.
一个恢复力受单基因控制的水稻CMS育性回复突变体 总被引:3,自引:0,他引:3
利用 ̄(60)Co-γ射线对具有印尼水田谷细胞质的籼稻细胞质雄性不育系Ⅱ-32A干种子进行诱变处理,获得了一育性回复突变体T24。育性基因未纯合的突变体分离出可育株和完全不育株,比例为3∶1;其与Ⅱ-32A和珍汕97A测交,F1代分离出1∶1的可育株和不育株。育性稳定株系与Ⅱ-32A和珍汕97A杂交,F2分离成3∶1的可育株和不育株。表明其育性回复是由一对基因显性突变所致。这一突变体对不育系的育性恢复机制不同于明恢63、20964等恢复系,后者表现为两对显性恢复基因作用。未观察到T24与亲本Ⅱ-32A除育性以外的其他性状的差异,因而两者构成育性恢复基因的近等基因系。本文还对不育系育性回复类型和T24的理论意义与育种价值进行了讨论。 相似文献
37.
Roberto MacChiarelli Luca Bondioli Laura Censi Margarita Kristoff Hernaez Loretana Salvadei Alessandra Sperduti 《American journal of physical anthropology》1994,95(1):77-83
Little attention has been devoted to assessing the reproducibility of (paleo)pathological observations. Harris lines (HL) are among the markers most used to determine chronology of stresses suffered during growth. Nevertheless, their scoring entails remarkable methodological difficulty. Bone sections (S) and radiographs (R) of 29 adult tibiae of archeological provenance (medieval) were scored for HL by five observers. At regular intervals of time, each observer gave two independent counts on both series. Results show a) a substantial interobserver disagreement of HL estimates for both sectional and radiographic records, and b) a high level of intraobserver error. © 1994 Wiley-Liss, Inc. 相似文献
38.
Konieczny and Ausubel have described a technique whereby Arabidopsis thaliana loci can be rapidly mapped to one of the ten chromosome arms using a small number of F2 progeny from crosses between the ecotypes Landsberg erecta and Columbia. The technique involves the use of 18 co-dominant, cleaved amplified polymorphic sequence (CAPS) markers which are evenly distributed throughout the Arabidopsis genome. We have mapped these 18 markers using recombinant inbred (RI) lines generated in our laboratory. These data enable a better integration of loci mapped relative to the CAPS markers into the restriction fragment length polymorphism (RFLP) map generated using Arabidopsis RI lines. 相似文献
39.
Virk D. S. Brar J. S. 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1993,87(1-2):106-112
Four near-isonuclear polycytoplasmic versions of 81A and two of Pb 402A male-sterile lines of pearl millet (Pennisetum typhoides) were used in factorial matings with five inbred male testers in different combinations in three sets. The cytoplasmic differences were studied for several agronomic traits using mean values and general combining effects (gca) of male-sterile lines, and specific combining ability effects of hybrids. The fertility/ sterility behaviour of different male-sterile lines in crosses with common male parents was also studied. Significant differences among near-isonuclear polycytoplasmic lines were observed in mean values for a few traits such as plant height, leaf length and peduncle length, but the differences for combining ability were more pronounced. The A3 cytoplasm was a better general combiner than the A2 cytoplasm for grain yield and both A2 and A3 cytoplasms were better general combiners for leaf length and peduncle length. In addition, superiority of A3 cytoplasm for gca was observed for plant height and ear characters over the A2 cytoplasm in set II. A differential behaviour of cytoplasms, both in combination with a common pollinator and across pollinators, was observed for several traits. The results provide evidence for the distinctiveness of different cytoplasmic sources in pearl millet and for the influence of cytoplasmic factors on the phenotypic expression of nuclear genes. A diversification of male sterility sources in the breeding of pearl millet hybrids is suggested. 相似文献
40.
S. Wright-Perkins M. R. Daniel C. Walker 《In vitro cellular & developmental biology. Animal》1994,30(7):450-459
Summary This study investigates the characteristics of two human cell lines—1PT and 1PT VARIANT A—both derived from the same histologically
undifferentiated, neuroendocrine positive, non-small cell lung carcinoma (NSCLC) and capable of growth in unsupplemented serum-free
minimum essential medium. In stationary culture, the cells of both lines grew both attached to a plastic substratum and in
suspension; the 1PT VARIANT A line formed three-dimensional clusters of loosely adherent cells. The cell lines differed in
their DNA content, the 1PT having 1.44 times and the 1PT VARIANT A having 2.39 times the normal human diploid DNA content.
Chromosome counts supported this observation, the ploidy of the 1PT and VARIANT A lines being 1.11 and 1.64, respectively.
On transmission electron microscopy the cells of both lines had dense core granules and immature desmosomes, whereas only
the 1PT VARIANT A line had mucin granules. Both lines formed, in nude mice, tumors that, like the original tumor from which
they were derived, were histologically undifferentiated and showed local invasion. The original tumor and both lines had demonstrable
neuroendocrine markers. Cytokeratins were apparent in the tumor but not the cell lines, and neurofilaments were present in
the cell lines only. Staining for epithelial membrane antigen, neural cell adhesion molecule, and desmoplakin differentiated
between the two lines. These lines provide a useful model for the investigation of the biology of the neuroendocrine positive
subgroup of NSCLC, which is clinically important because of the possible responsiveness of these tumors to chemotherapy. 相似文献