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Rolando Campos Argelia Garrido Ricardo Guerra Alfonso Valenzuela 《Free radical research》1990,10(4):259-264
Reperfusion of rat kidney submitted to temporal ischaemia induces a decrease in glutathione content. Lipid peroxidation is not detected in kidney homogenates but microsomes obtained after periods of reperfusion longer than 60 minutes show increased malondialdehyde values correlated with high oxygen consumption and superoxide free radical generation. Microsomes obtained from kidneys submitted to 15 or 60 minutes of reperfusion are resistant to NADPH-induced lipid peroxidation but after 120 minutes of reperfusion an increased lipid peroxidative response is observed. Although the mechanism of the protection found in microsomes against the induction of oxidative stress in the first 60 minutes of reperfusion is unknown, it is postulated that this subcellular fraction plays an important role in the oxidative stress observed after longer periods of reperfusion. 相似文献
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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
36.
A new taxonomic treatment is proposed for thePottia starckeana species complex. The peristome development is not considered to be a useful feature to separate the taxa. On the basis of spore morphology only two species are accepted:P. starckeana, with spores wavy in outline, andP. davalliana, with variously-shaped and developed processes on the spores.Pottia starckeana var.brachyoda is reduced to synonymy withP. starckeana; P. conica andP. commutata are treated as synonyms ofP. davalliana. The speciesP. mutica, P. affinis, P. salina, P. microphylla, P. texana, andP. arizonica (included var.mucronulata) are considered taxa of doubtful affinity, as they have spore features intermediate between the two spore types established for the group. The identity ofP. appertii andP. recurvifolia has not been elucidated because the type material has been destroyed. 相似文献
37.
Analyses of cooling rates in one Adélie and one Humboldt penguin yielded calculated thermal conductance values of 0.1040
and 0.1672 W(kg °C)-1, respectively. We review the methods used to calculate penguin surface area, an important component in calculating conductance
values, and suggest that, in comparative studies of thermal balance, the use of body mass is a better estimator of body size
than surface area. Using previously published data on penguin species, we found a significant model to predict thermal conductance
from body mass according to: log C= log 0.1083−0.474 log M, where C is minimal specific thermal conductance in W(kg °C)-1 and M is body mass in kilograms.
Received: 13 June 1995/Accepted: 11 March 1996 相似文献
38.
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
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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
39.
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40.
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