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Sonoko Ogawa John D. Gordan Julia Taylor Dennis Lubahn Kenneth Korach Donald W. Pfaff 《Hormones and behavior》1996,30(4):487-494
Effects of gene products on reproductive behavior which are relatively direct include those of the estrogen receptor and progesterone receptor. For example, work with estrogen receptor-deficient (ERKO) female mice has extended previous evidence contributing to the neurochemical analysis of lordosis behavior. On the other hand, sex differences in behavior present a classic example of indirect effects of genes on behavior. Work with ERKO male mice shows the necessity of ER gene expression for normal masculinization of the brain. In particular, behavioral assay results distinguish apparent motivational performance of ERKO males from male mating reflexes: the former is similar to that of wild-type males in important respects, while the latter are deficient in ERKO males. The present paper first reviews a small number of clear genetic contributions to reproductive behaviors, and then reports one experiment pertinent to the interpretation of the behavioral status of ERKO male mice. 相似文献
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Fine mapping of the Autosomal Dominant Split Hand/Split Foot Locus on Chromosome 7, Band q21.3-q22.1 总被引:6,自引:3,他引:3 下载免费PDF全文
Stephen W. Scherer Parvoneh Poorkaj Todd Allen Julia Kim Dorrit Geshuri Mark Nunes Sylvia Soder Karen Stephens Roberta A. Pagon Michael A. Patton Mary Anne Berg Tim Donlon Horacio Rivera R. A. Pfeiffer Kenji Naritomi Helen Hughes Maurizio Genuardi Fiorella Gurrieri Giovanni Neri Everett Lovrein Ellen Magenis Lap-Chee Tsui James P. Evans 《American journal of human genetics》1994,55(1):12-20
Split hand/split foot (SHFD) is a human developmental defect characterized by missing digits, fusion of remaining digits, and a deep median cleft in the hands and feet. Cytogenetic studies of deletions and translocations associated with this disorder have indicated that an autosomal dominant split hand/split foot locus (gene SHFD1) maps to 7q21-q22. To characterize the SHFD1 locus, somatic cell hybrid lines were constructed from cytogenetically abnormal individuals with SHFD. Molecular analysis resulted in the localization of 93 DNA markers to one of 10 intervals surrounding the SHFD1 locus. The translocation breakpoints in four SHFD patients were encompassed by the smallest region of overlap among the SHFD-associated deletions. The order of DNA markers in the SHFD1 critical region has been defined as PON–D7S812–SHFD1–D7S811–ASNS. One DNA marker, D7S811, detected altered restriction enzyme fragments in three patients with translocations when examined by pulsed-field gel electro-phoresis (PFGE). These data map SHFD1, a gene that is crucial for human limb differentiation, to a small interval in the q21.3-q22.1 region of human chromosome 7. 相似文献
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Research Notes on Avian Biology 1994: Selected Contributions from the 21st International Ornithological CongressMorphology and Physiology: Orientation
Subject: Navigation and orientation 相似文献28.
Julia F. Morton 《Economic botany》1994,48(3):259-270
Lantana, or red sage (lantana camara, Verbenaceae) is an aromatic shrub with rough, opposite or whorled leaves and four-angled, prickly or smooth stems, showy heads of small flowers (usually pink-and-yellow changing to red-and-orange) and dark-blue or blackish fruits. Native from tropical America north to lower Texas and southern Georgia, the bird-distributed plant has become naturalized in the Caribbean area, the Pacific islands, Australia, New Zealand, South Africa and southern Asia. Hundreds of cultivars are grown as ornamentals in temperate climates. In warm regions, L. camara is a pest in farms, pastures and forests, providing breeding places for diseases, detrimental animals and insects, including the tsetse fly. Of 29 named races in Australia, 19 are toxic or gravely pestiferous. Active principles are the triterpenes lantadene A and B. Ingestion of 340-453 g of leaves causes liver and kidney damage, photosensitization, intestinal hemorrhage, paralysis of the gall bladder, and death in 1-4 days in horses, cattle and sheep (not goats). Ripe fruits are edible, but green, unripe fruits have caused illness and one known fatality in children in Florida. Leaves and roots are popular folk remedies. Stems are used as toothbrushes, and the leaves for polishing wood. Prickly races are grown as protective hedges around forest dwellings. 相似文献
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The HLA class II sequences included in this compilation are taken from publications listed in the papers: Nomenclature for factors of the HLA system, 1989, Nomenclature for factors of the HLA system, 1990, and Nomenclature for factors of the HLA system, 1991 (WHO Nomenclature Committee 1990, 1991, 1992). Where discrepancies have arisen between reported sequences, the original authors have been contacted where possible, and necessary amendments to published sequences have been incorporated into this alignment. Future sequencing may identify errors in this list, and we would welcome any evidence that helps to maintain the accuracy of this compilation. In the sequence alignments, identity between residues is indicated by a hyphen (-), an unavailable sequence is indicated by an asterisk (*), and gaps in the sequence are inserted to maintain the alignment between different alleles showing variation in amino acid number.
Correspondence to: S. G. E. Marsh. 相似文献
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Addition of polyamines or their analogs to newly confluent LLC-PK1 cells resulted in down-regulation of Na+-glucose transport (symport) activity. Polyamines prevented the induction of this symporter by the differentiation inducer hexamethylene bisacetamide (HMBA) but did not influence induction by the phosphodiesterase inhibitor 3-isobutyl-1-methylxanthine (IBMX). Partial depletion of endogenous polyamines after addition of α -difluoromethylornithine (DFMO) resulted in a 4 to 5-fold increase in symporter expression. Symporter induction by either HMBA or DFMO was inhibited by the protein kinase inhibitor H-7 but H-7 did not affect symporter induction by IBMX. Changes in symporter activity were accompanied by changes in levels of the 75 kD symporter subunit detected by Western blot. Cultures exposed to HMBA exhibited reduced levels of ornithine decarboxylase activity. Our results suggest that induction of symporter expression by HMBA may be mediated in part by its effects on polymine metabolism, and point to parallel roles of polyamines and cyclic AMP in regulating the expression of this physiologically important renal transport system. © 1993 Wiley-Liss, Inc. 相似文献