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排序方式: 共有1512条查询结果,搜索用时 46 毫秒
41.
Summary A patient with acute lymphoblastic leukemia (ALL) whose cells had L3 (Burkitt-type) morphology was found to have a variant translocation t(2;8)(p13;q24), that has been reported only in Burkitt lymphomas. This observation provides additional evidence for a close association of particular karyotypic abnormalities with both Burkitt-type ALL and Burkitt lymphoma. 相似文献
42.
The Porella liverworts contain abundant sesquiterpenes. ent-Biocyclogermacrene, three ent-aromadendrenes, a unique hydrocarbon, α-pinguisene and two drimane type sesquiterpenes were obtained together with the intensly pungent component, tadeonal, from P. vernicosa and P. gracillima. P. macroloba contained the same sesquiterpenes except for the absence of ent-bicyclogermacrene and the ent-aromadendrenes. The fragrant odor of P. perrottetiana was composed of α-pinene and camphor. 相似文献
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45.
Fumio Sawada Yasuhiko Miyauchi Hiroshi Tanaka Shinji Matsumoto 《Biochemical and biophysical research communications》1982,104(2):657-663
A novel method for the preparation of intact chromatin from the slime mold which retains the property of RNA synthesis is described. Preparations from G2-cells were highly active, while those from metaphase-cells were inactive. The plasmodial cells were disrupted by gentle homogenization on a polyethylene sieve in a neutral isotonic sucrose medium containing Mg++, deoxycholate and EGTA, a Ca++-chelating agent. The nuclei were lysed in a hypotonic buffer without use of EDTA and chromatin was precipitated by centrifugation after addition of Mg++. 相似文献
46.
Kohei Kawashima Eiji Watanabe Ken-ichi Isobe Michinori Ogura Ei-ichi Nagura Kazumasa Yamada Itsuro Sobue Kenji Mizoguchi Yasuhiko Ito Yoshiyuki Nagai Izumi Nakashima 《Cellular immunology》1982,67(2):279-286
During the course of immunization of (C3H × DBA/2)F1 mice (genotype H-2k/b) with L cell (H-2k/k)/L1210 leukemia cell (H-2d/d) hybrids and L1210 leukemia cells, some of them produced a good titer of anti-self-H-2 (H-2d) antibodies. Antigens recognized by this anti-self-H-2 antiserum were shown to be controlled by the H-2K-IA-IB-IJ-IE subregions of the H-2d but not H-2k nor H-2b haplotypes of parental as well as F1 origins and to have a tissue distribution identical to that of class 1 H-2 (H-2K/D) antigens. 相似文献
47.
J Nakura T Miki K Nishikawa Y Takemoto K Kamino S Takai K Hayashi T Ogihara 《Endocrinologia japonica》1990,37(5):615-618
Early prenatal diagnosis of 21-hydroxylase (21-OHase) deficiency would enable treatment to be done to protect the fetus from masculinization and/or life-threatening adrenal crisis at birth. We report here the prenatal diagnosis of 21-OHase deficiency with human complement component C4 cDNA to probe DNA from chorionic villi at 10 weeks of gestation. Southern analysis with human C4 cDNA identified TaqI restriction fragment length polymorphisms (RFLPs) in the family. Family analysis with these RELPs showed that the fetus was not affected at greater than 99% probability, because the frequency of recombination between the 21-OHase B gene and the C4 gene would be extremely low. 相似文献
48.
Hiroaki Nakayama Koji Nakayama Ritsuko Nakayama Yasuhiko Kato 《Archives of microbiology》1982,131(4):308-312
Hydrophobic and charge-charge interactions of Salmonella typhimirium and Serratia marcescens were determined and related to their content of fimbriae and lipopolysaccharide (LPS). The cell surface structures were characterized with hydrophobic interaction chromatography (HIC), electrostatic interaction chromatography (ESIC) and particle electrophoresis measurements. The degree of interaction at the air-water interface was tested using a monolayered lipid film applied to an aqueous surface. The cell surface hydrophobicity of S. typhimurium in the presence of fimbriae was less in smooth than in rought bacteria. Examination of a series of rough mutants of S. typhimurium indicates that reduction of the O-side chain and core oligosaccharides was correlated with increased cell hydrophobicity. The enrichment factors at the air-water interface were significantly higher for fimbriated than for non-fimbriated S. typhimurium cells. Fimbriated S. marcescens cells were less hydrophobic and adhered to a lesser degree at the air-water surface than non-fimbriated counterparts. Electrophoretic measurements and adsorption to ion exchangers gives different information about the surface charge of bacteria. The latter technique gives the interaction between localized charged surfaces.Abbreviations HIC
hydrophobic interaction chromatography
- ESIC
electrostatic interaction chromatography
- LPS
lipopolysaccharide
- PBS
phosphate buffered saline solution 相似文献
49.
Biological and biochemical studies of African green monkey lymphotropic papovavirus. 总被引:12,自引:10,他引:2
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The growth of African green monkey lymphotropic papovavirus (LPV) in human lymphoblastoid cell line BJA-B was found to be slow and inefficient due to the accumulation of defective particles. An analysis of molecularly cloned LPV DNAs showed that 3 of 19 clones had DNAs that were longer (5.1 kilobases) than the DNAs of the other clones. The 5.1-kilobase DNA was infectious for BJA-B cells, whereas the shorter (4.8-kilobase) molecules were defective. Unlike the wild-type virus, stocks of LPV made from cloned, infectious DNAs were homogeneous and had higher titers. Using stocks of nondefective LPV, we investigated other biological properties. LPV replication in another human B-lymphoblastoid cell line was observed. The virus did not cause tumors when it was inoculated into newborn hamsters. Serological surveys of human and nonhuman primate sera indicated that virtually all primates, including humans, show evidence of infection by viruses antigenically related to LPV. 相似文献
50.
Yoshinori Asakawa Masao Toyota Reiji Takeda Claude Suire Tsunematsu Takemoto 《Phytochemistry》1981,20(4):725-728
Riccardia species (Metzgeriales) contain various types of sesquiterpenes. R. jackii produces ent-selinane-, ent-aromadendrane-and ent-bicyclogermacrane-type sesquiterpenes together with (R)-cuparene and α-barbatene. Aneura pinguis (= Riccardia pinguis) is chemically quite different from R. multifida and R. jackii. The former produces a large amount of pinguisone. R. multifida contains 6-(3-methyl-2-butenyl)-indole and (+)-β-elemene as the major components. Pallavicinia longispina (Dilaenaceae; Metzgeriales) produces mainly spathulenol. The chiral properties of the sesquiterpenes isolated from R. jackii are quite similar to those of red algae, Laurencia species. 相似文献