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排序方式: 共有250条查询结果,搜索用时 9 毫秒
241.
P E Sudbery M A Gleeson R A Veale A M Ledeboer M C Zoetmulder 《Biochemical Society transactions》1988,16(6):1081-1083
The advantages of Hansenula polymorpha as a new yeast expression system are discussed in terms of the powerful and regulatable methanol oxidase promoter and the organism's ability to grow on cheap carbon sources. The development of techniques for conventional genetic analysis is described. A total of 218 mutants have been assigned to 62 complementation groups, three genes have been found to be linked forming the first linkage group in this organism. Methods for molecular transformation have been developed allowing the expression of heterologous genes. The disruptive integration and expression of the neomycin phosphotransferase is described. 相似文献
242.
243.
244.
245.
Neuropeptide Y, PYY, and PP (200 pmol) alter intraluminal pressure in the duodenum and colon of rats following their administration into the thoracic (T8-T10) region of the spinal cord. Neuropeptide Y decreases the tone of the duodenum and the colon following intrathecal (T8-T10) administration prior to an increase in tone to baseline or greater. There is no effect on intraluminal pressure of either the duodenum or the colon following intrathecal administration of NPY or PP into the lumbar (L4-L5) region of the spinal cord. Following intrathecal (T8-T10) administration of PYY and PP, increases in intraduodenal pressures are observed (+2.1 and +3.0 mmHg from saline baseline). Phasic contractions of the duodenum are increased following intrathecal administration of PYY into the thoracic spinal cord of rats. Neuropeptide Y, PYY, and PP increase intracolonic pressure +2.2, +3.3, and +3.7 mmHg from saline baseline, respectively. Phasic contractions of the colon are increased following PP intrathecal thoracic administration. Responsiveness of the duodenum or colon to the different ligands of the PP-fold peptide family in the absence of alpha-adrenergic blockade did not vary. The increases in intraluminal pressure of the duodenum and colon following intrathecal administration of the PP-fold peptides are attenuated by both alpha-1 adrenergic (prazosin) and alpha-2 adrenergic (yohimbine) blockade. There is a difference in responsiveness of the colon between the ligands of the PP-fold family in the presence of the alpha-2 adrenergic blockade. The findings of this study indicate that duodenal and colonic motility are modulated by the PP-fold peptides at thoracic spinal sites via alteration of sympathetic outflow. 相似文献
246.
The toxicity of gonococci [strain BS4 (agar)] for human peripheral blood polymorphonuclear phagocytes, infected in vitro, was assessed by light microscopic examination of Giemsa stained cell deposits of polymorphonuclear phagocytes which had ingested these bacteria. The cytotoxicity elicited by viable gonococci, assessed by percentage lysis and concomitant reduction in the number of polymorphonuclear phagocytes increased as the ratio of gonococci to phagocytes in the original suspension mixture was raised. Pretreatment of viable gonococci with antiserum raised to whole organisms increased the cytotoxic effect produced by the organisms. Killed (heat or UV irradiation) gonococci caused little or no cytotoxicity, even when the organisms were pretreated with specific antiserum. Hence, the lysis of polymorphonuclear phagocytes appears to be caused by a factor or factors produced by viable gonococci and not by LPS per se. 相似文献
247.
194 cord blood samples were studied in both a fluorimetric assay and an electrophoresis method for Gal-1-PUT. From this the expected live birth incidence was 1:37000. The New Zealand neonatal screening programme has detected 5 cases in 223326 live births--an apparent incidence of 1:44600. The Beutler testing of dried blood spots collected on filter paper cards is a satisfactory method of detecting galactosaemia in the neonate. 相似文献
248.
The nucleotide sequence data reported in this paper have been submitted to the GenBank nucleotide sequence database and have been assigned the accession numbers M77670 (DRB1
*
AB3), M77671 (DRB1
*
AB4), MM77672 (DRB1
*
AB2), MM77673 (DRB1*A01), M81670 (DRB1*0410), and M81700 (DRB1
*
0411). 相似文献
249.
The molecular organization of the beta-globin complex of the deer mouse, Peromyscus maniculatus 总被引:1,自引:0,他引:1
Padgett RW; Loeb DD; Snyder LR; Edgell MH; Hutchison CA d 《Molecular biology and evolution》1987,4(1):30-45
Recombinant DNA clones have been isolated that contain 80 kb of the
beta-globin complex from the deer mouse, Peromyscus maniculatus.
Comparisons of this complex with that from the laboratory mouse, Mus
domesticus (with an order 5'-Hbby, Hbb-bhO, Hbb-bhl, Hbb-bh2, Hbb-bh3,
Hbb-bl, Hbb-b2 3') highlight organizational trends in the beta-globin
complex since the two species diverged. Unlike other mammals studied thus
far, the deer mouse possesses three adult genes. Partial sequence analysis
indicates that each of the three adult genes is intact and hence may be
functional. Hybridization of one of the two Mus pseudogenes, Hbb-bh3, to
genomic blots from Peromyscus reveals that it has a homologous counterpart
in Peromyscus. Homologous genes to the two gamma-like Mus genes, Hbb-bhO
and Hbb-bhl, are also found in Peromyscus. The strong hybridization between
the Hbb-bhl genes and significant nucleotide similarity between the Hbb-bhO
genes suggest that both pairs are important for the ontogeny of these mice
although no known product has been identified for the Hbb-bhO genes. The
presence of Hbb-bhO and Hbb-bhl in Peromyscus suggests that the duplication
that created this related gene set occurred before the two lineages
diverged. A single gene for Hbb-y has been isolated from Peromyscus. The
adult region in Peromyscus has undergone significant divergence from the
same region in Mus, having three rather than two adult genes, the
acquisition of at least 15 kb of extra DNA relative to Mus, and possibly
the loss of the Hbb-bh2 pseudogene. The nonadult region of the complex, in
contrast, contains the same set of genes apparently distributed over the
same amount of DNA as in the Mus beta- globin complex. This observation
suggests that the embryonic region of the complex is more evolutionarily
stable than the adult region.
相似文献
250.
Infection of subcutaneusly implanted chambers in guinea pigs conferred immunity against homologous infection of other chambers in the same animals. However, attempts to immunize guinea pigs by subcutaneous injection of filtered fluid from infected chambers, or with small doses of formalin-killed, chamber gonococci were not successful. Thus, neither organisms grown in vivo nor their extracellular products appeared to be exceptionally immunogenic. In immunizing tests with different isolates of gonococci adapted to growth in guinea-pig chambers, cross-immunity to chamber infection with low challenge doses was detected only between two of six isolates. The killing of gonococci in chambers of immunized animals, which occurred only after homologous challenge or with the heterologous strain showing cross-immunity, was not due primarily to humoral factors in the chamber fluid but probably to an enhanced effectiveness of phagocytosis. The serum of immunized animals was bactericidal for homologous strains and for the strain showing cross-immunity but not for strains showing no cross-immunity. Hence, serum bactericidal activity might be a useful indicator for investigating the specificity of immunity produced by different gonococcal strains. 相似文献