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91.
92.
Johanna Lass-Hennemann Christian E. Deuter Linn K. Kuehl André Schulz Terry D. Blumenthal Hartmut Schachinger 《Proceedings. Biological sciences / The Royal Society》2010,277(1691):2175-2183
Although humans usually prefer mates that resemble themselves, mating preferences can vary with context. Stress has been shown to alter mating preferences in animals, but the effects of stress on human mating preferences are unknown. Here, we investigated whether stress alters men''s preference for self-resembling mates. Participants first underwent a cold-pressor test (stress induction) or a control procedure. Then, participants viewed either neutral pictures or pictures of erotic female nudes whose facial characteristics were computer-modified to resemble either the participant or another participant, or were not modified, while startle eyeblink responses were elicited by noise probes. Erotic pictures were rated as being pleasant, and reduced startle magnitude compared with neutral pictures. In the control group, startle magnitude was smaller during foreground presentation of photographs of self-resembling female nudes compared with other-resembling female nudes and non-manipulated female nudes, indicating a higher approach motivation to self-resembling mates. In the stress group, startle magnitude was larger during foreground presentation of self-resembling female nudes compared with other-resembling female nudes and non-manipulated female nudes, indicating a higher approach motivation to dissimilar mates. Our findings show that stress affects human mating preferences: unstressed individuals showed the expected preference for similar mates, but stressed individuals seem to prefer dissimilar mates. 相似文献
93.
Arun Goyal 《FEMS microbiology letters》1989,61(1-2):145-148
Abstract When Dunaliella tertiolecta cells are subjected to a dilution stress (hypoosmotic shock) the intracellular glycerol is metabolised biochemically, but it does not leak into the medium. However, Dunaliella cells have a certain 'threshold' to withstanding a hypoosmotic shock beyond which cell damage occurs and then glycerol is leaked into the medium. Both in the light or the dark, the glycerol metabolism was inhibited by micromolar concentration of carbonylcyanide m - chlorophenyl - hydrazone (CCCP) suggesting that the required ATP for the glycerol dissimilation is dependent upon an energized membrane, and most of which can be supplied through the oxidative phosphorylation. 相似文献
94.
Maize pyruvate decarboxylase mRNA is induced anaerobically 总被引:13,自引:0,他引:13
Philip M. Kelley 《Plant molecular biology》1989,13(2):213-222
A cDNA was identified using an oligonucleotide designed by comparing the sequences of bacterial and yeast pyruvate decarboxylase. The sequence of the cDNA identified by the oligonucleotide contained an open reading frame that encoded a protein of 65 kDa that was similar in sequence to bacterial and yeast pyruvate decarboxylase. This protein was selectively precipitated by an antiserum specific for maize PDC. Northern-blot analysis shows that PDC mRNA is anaerobically induced. Southern-blot analysis of maize genomic DNA indicated that the maize PDC gene has a single or low copy number. 相似文献
95.
96.
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98.
GREGOR HASLER 《World psychiatry》2010,9(3):155-161
Due to the clinical and etiological heterogeneity of major depressive disorder,
it has been difficult to elucidate its pathophysiology. Current neurobiological
theories with the most valid empirical foundation and the highest clinical
relevance are reviewed with respect to their strengths and weaknesses. The
selected theories are based on studies investigating psychosocial stress and
stress hormones, neurotransmitters such as serotonin, norepinephrine, dopamine,
glutamate and gamma-aminobutyric acid (GABA), neurocircuitry, neurotrophic
factors, and circadian rhythms. Because all theories of depression apply to
only some types of depressed patients but not others, and because depressive
pathophysiology may vary considerably across the course of illness, the current
extant knowledge argues against a unified hypothesis of depression. As a consequence,
antidepressant treatments, including psychological and biological approaches,
should be tailored for individual patients and disease states. Individual
depression hypotheses based on neurobiological knowledge are discussed in
terms of their interest to both clinicians in daily practice and clinical
researchers developing novel therapies. 相似文献
99.
100.
Lisa Clayton Christopher Hiley Simon Davies Richard D'souza Peter Jones Richard Strange Geoffrey Aber 《Free radical research》1992,17(4):271-278
The sensitivity of isolated glomeruli from normotensive (Wistar-Kyoto, WKY) and spontaneously hypertensive (SHR) strains to oxidant stress was studied by determining the incidence of pyknosis, karyohexis and karyolysis after incubation with different concentrations of hydrogen peroxide (H2O2) (4.7 × 10-9-10-3 M). Even though the proportion of glomeruli containing nuclei that demonstrated these features increased progressively with increasing concentrations of H2O2, the number of severely damaged glomeruli was relatively small even at concentrations of 4.7 × 10-3 M.
Examination of the surface epithelial cells of glomeruli using scanning electron microscopy revealed no evidence of disturbance of the macroscopic or podocyte structure or, of increased blebbing after H2O2-treatment. These data suggest damage to nuclei is an early result of ROS stress on glomeruli.
Preincubation of WKY glomeruli with captopril or lisinopril resulted in a significant drop in the proportion of WKY glomeruli demonstrating structural damage after oxidant stress. In contrast, preincubation of SHR glomeruli with lisinopril had no effect on oxidant-induced changes in the morphology of SHR glomeruli, whereas captopril effected a significant increase in the proportion of glomeruli demonstrating damage at all concentrations of H2O2. 相似文献
Examination of the surface epithelial cells of glomeruli using scanning electron microscopy revealed no evidence of disturbance of the macroscopic or podocyte structure or, of increased blebbing after H2O2-treatment. These data suggest damage to nuclei is an early result of ROS stress on glomeruli.
Preincubation of WKY glomeruli with captopril or lisinopril resulted in a significant drop in the proportion of WKY glomeruli demonstrating structural damage after oxidant stress. In contrast, preincubation of SHR glomeruli with lisinopril had no effect on oxidant-induced changes in the morphology of SHR glomeruli, whereas captopril effected a significant increase in the proportion of glomeruli demonstrating damage at all concentrations of H2O2. 相似文献