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171.
Summary Recombination of an inherited pericentric inversion of chromosome 20 has given rise to a child with partial trisomy 20p. To our knowledge no previous familial inversions of this chromosome have been described in the literature. 相似文献
172.
Oligomycin sensitivity conferral protein (OSCP), factor 6 (F6), and ATPase inhibitor protein are all components of the ATP synthase complex of bovine mitochondria. They are encoded in nuclear DNA. Complementary DNA clones encoding the precursors of these proteins have been isolated from a bovine library by using mixtures of synthetic oligonucleotides as hybridization probes, and their DNA sequences have been determined. The deduced protein sequences show that the OSCP, F6, and inhibitor proteins have N-terminal presequences of 23, 32, and 25 amino acids, respectively. These presequences are not present in the mature proteins. It is assumed that they serve to direct the proteins into the mitochondrial matrix. The cDNA clones have also been employed as hybridization probes to investigate the genetic complexity of the three proteins in cows and humans. These experiments indicate that the bovine and human inhibitor and bovine F6 proteins are encoded by single genes but suggest the possibility of the presence in both species of more than one gene (or pseudogenes) for the OSCP. 相似文献
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C57BL/6 nude beige mice (B6 nubq; no T cell, no NK activity) were used as recipients for the adoptive transfer of thymocytes from B6 gld mice (generalized lymphoproliferative disease) which are a model of systemic lupus erythematous. The [gld----nubg] chimeras showed several similarities with gld control mice including the T cell disorders (lymphoproliferation and Con A-response deficiency of splenocytes) and B cell disorders (hyperglobulinemia and elevated anti-single-stranded DNA antibody titers). This suggests that the gld lymphoproliferative disorder has a thymic origin (and does not result from an abnormally extrathymic T cell development) and that the gld T cells have an essential role for the emergence of the disorders of both the T and B cells. 相似文献
177.
Prostaglandin (PG) stimulates female spawning behavior in goldfish and in some other teleosts in which female reproductive behaviors consist of postovulatory oviposition acts. This study examined the effects of PG on female sexual behavior in a teleost fish, Cichlasoma bimaculatum, in which female reproductive behaviors involve both preovulatory courtship and substrate cleaning behaviors, and post-ovulatory oviposition behavior. In females of established pairs, PGF2 alpha injection (5 micrograms, im) at any stage of the spawning cycle, or in the parental phase, rapidly induced substrate cleaning which soon merged into oviposition behavior (without egg release). These results support a role for PG in oviposition behavior of Cichlasoma. However, indomethacin (1 mg, ip), a PG synthesis inhibitor, did not block oviposition in ovulated females which had begun to spawn. Indomethacin may not have lowered PG levels sufficiently. Alternatively, as shown by J.J. Polder (1971, Neth. J. Zool. 21, 265), oviposition behavior may be induced or maintained by other factors associated with the spawning situation. 相似文献
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