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A Mueller H Binder S Cupisti I Hoffmann M W Beckmann R Dittrich 《Hormones et métabolisme》2006,38(3):183-187
We studied hormonal changes resulting from long-term treatment with gonadotropin-releasing hormone agonist and 17beta estradiol valerate in 40 healthy middle-aged male-to-female transsexuals over a period of two years. All of the participants received injections of 3.8 mg goserelin acetate every four weeks in combination with 6 mg oral 17beta estradiol valerate per day for cross-sex hormone treatment for male-to-female transsexuals. There was a significant reduction in the levels of serum luteinizing hormone and follicle-stimulating hormone to the hypogonadal stage. Mean testosterone levels decreased by 97% to 0.52 and 0.59 nmol/l after 12 months and 24 months, respectively. There was a significant reduction in dehydroepiandrosterone sulfate by 37% after 12 months and 43% after 24 months, and androstendione by 29% after 12 months and 27% after 24 months, respectively. Cortisol levels were reduced by 43% and 50%, respectively. Estrogen levels were significantly increased from 77.51 to 677 after 12 months and 661 pmol/l after 24 months. Sex hormone-binding globulin and corticoid-binding globulin levels were significantly increased after 12 and 24 months. There was a significant decrease in all measured androgen fractions and cortisol during long-term treatment with gonadotropin-releasing hormone agonist and 17beta estradiol valerate. Apart from suppression of testicular hormone production, one possible interpretation is that treatment with long-term gonadotropin-releasing hormone agonist and 17beta estradiol valerate influences adrenal hormone levels in healthy middle-aged male-to-female transsexuals. Cortisol serum levels may be decreased due to estrogen-induced increase in corticoid-binding globulin. 相似文献
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This study investigated the effects of long-term cyproterone-acetate (CA) treatment on the hypothalamus-pituitary-adrenal axis and further on the release of prolactin and growth hormone. Thirty-one male-to-female transsexuals, treated at least 3 months either with 100 mg CA alone or in combination with 50 micrograms ethinyloestradiol (EO)/day, were studied. In all of them the cortisol response to 250 micrograms Synacthen administration was comparable to that measured in controls. Six subjects treated with CA alone (group I) and six subjects treated with CA + EO (group II) underwent an insulin-hypoglycemia test. Seven eugonadal men served as controls. Compared with control values: in two subjects of group I and one subject of group II a low cortisol response was found. The mean growth hormone response was found to be lower in both groups, whereas the mean prolactin response was lower in group I. 相似文献
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Estimating the ecological status and change of riparian zones in Andalusia assessed by multi-temporal AVHHR datasets 总被引:1,自引:0,他引:1
Following the European Commission's Water Framework Directive all surface waters in EU's Member States must reach a good status by 2015. The evaluation of this status will be partly based on ecological criteria, such as the hydro-morphological quality criteria which also evaluate the structure and condition of the riparian zone. Riparian zones with undisturbed or nearly undisturbed condition are given high-ecological status. The agri-environmental measures in the EU promote an extensive use of land to protect the farmed environment and its biodiversity. Recent studies in Andalusia and elsewhere suggest that extensification leads to riparian zones with higher ecological status compared to intensively used areas. We suggest that extensification and thus better ecological status of the riparian zone can be partly approximated by the amount of vegetation permanently present on the area. For this the so-called permanent vegetation fraction was derived from a multi-temporal advanced very high-resolution radiometer (AVHRR) dataset and was used (1) to classify the ecological status of the riparian zone into two classes, favourable and unfavourable, and (2) to assess the effect of agricultural practices on these areas. The classification was validated by field observations in the Guadalquivir river basin while detailed information on farming practices helped to assess the effect of agriculture on the riparian zone. The assessment was carried out in olive land cover because erosion control in olive cultivations is the most widely implemented measure in Andalusia. Results suggest that the remotely sensed permanent vegetation fraction is a good indicator of the favourable and unfavourable ecological status of the riparian zone. Furthermore, extensification of agricultural practices expressed in terms of increasing permanent vegetation cover was shown to have positive effect on the riparian zone as opposed to areas where no measures were implemented. 相似文献
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Background
Details of functional speciation within gene families can be difficult to identify using standard multiple sequence alignment (MSA) methods. The evolutionary trace (ET) was developed as a visualization tool to combine MSA, phylogenetic and structural data for identification of functional sites in proteins. The method has been successful in extracting evolutionary details of functional surfaces in a number of biological systems and modifications of the method are useful in creating hypotheses about the function of previously unannotated genes. We wish to facilitate the graphical interpretation of disparate data types through the creation of flexible software implementations. 相似文献6.
Haley A. Nolen Justin Xavier Moore Joel B. Rodgers Henry E. Wang Lauren A. Walter 《The Yale journal of biology and medicine》2016,89(2):131-142
Despite historical gender bias against female physicians, few studies have investigated patients’ physician gender preference in the emergency department (ED) setting. We sought to determine if there is an association between ED patient demographics and physician gender preference. We surveyed patients presenting to an ED to determine association between patient demographics and patient physician gender preference for five ED situations: 1) ‘routine’ visit, 2) emergency visit, 3) ‘sensitive’ medical visit, 4) minor surgical/‘procedural’ visit, and 5) ‘bad news’ delivery. A total of 200 ED patients were surveyed. The majority of ED patients reported no physician gender preference for ‘routine’ visits (89.5 percent), ‘emergent’ visits (89 percent), ‘sensitive’ medical visits (59 percent), ‘procedural’ visits (89 percent) or when receiving ‘bad news’ (82 percent). In the setting of ‘routine’ visits and ‘sensitive’ medical visits, there was a propensity for same-sex physician preference. 相似文献
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Epele ME 《Culture, medicine and psychiatry》2002,26(1):33-54
In this article I propose that genderinequality promotes – directly or indirectly –vulnerability to HIV as a consequence of amultidimensional violence (structural, symbolicand physical) experienced by injection drugusing (IDU) women in The Mission District (SanFrancisco). Given the female subordinated positionstipulated by the street ideology, I analyzehow drug dependence afforded by precariousstrategies of subsistence places IDU womenunder multiple dangers and threats. In thissetting, unequal gender relations are part of acomplex system of transactions in the streeteconomy and a way to reduce or increase theeveryday violence. Facing multiple dangers andrisks, some women adopt a subordinatedposition, some try to negotiate the conditionsof the exchanges and the others resist theexploitation. Finally, everyday violence under conditions ofgender inequality and scarcity of resourcesimposes a logic defined by the challenge ofsurvival under the threat of immediate dangers,which transform HIV into a secondary risk. 相似文献
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What role does personality play in the pervasive gender gap in entrepreneurship across the globe? This two-study analysis focuses on self-employment in the working population and underlying gender differences in personality characteristics, thereby considering both single trait dimensions as well as a holistic, configural personality approach. Applying the five-factor model of personality, Study 1, our main study, investigates mediation models in the prediction of self-employment status utilizing self-reported personality data from large-scaled longitudinal datasets collected in the U.S., Germany, the U.K., and Australia (total N = 28,762). Study 2 analyzes (observer-rated) Big Five data collected in 51 cultures (total N = 12,156) to take a more global perspective and to explore the pancultural universality of gender differences in entrepreneurial personality characteristics. Across the four countries investigated in Study 1, none of the major five dimension of personality turned out as a consistent and robust mediator. In contrast, the holistic, configural approach yielded consistent and robust mediation results. Across the four countries, males scored higher on an entrepreneurship-prone personality profile, which in turn predicted self-employment status. These results suggest that gender differences in the intra-individual configuration of personality traits contribute to the gender gap in entrepreneurship across the globe. With the restriction of limited representativeness, the data from Study 2 suggest that the gender difference in the entrepreneurship-prone personality profile (males score higher) is widespread across many cultures, but may not exist in all. The results are discussed with an emphasis on implications for research and practice, which a particular focus on the need for more complex models that incorporate the role of personality. 相似文献
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Traci Ardren 《American anthropologist》2001,103(2):552-553
Manifesting Power: Gender and the Interpretation of Power in Archaeology. Tracy L. Sweety. ed. New York: Routledge, 1999.210 pp. 相似文献
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Kevin McGrath 《American anthropologist》2000,102(2):417-417
Splitting the Difference: Gender and Myth in Ancient Greece and India. Wendy Doniger. Chicago, EL: University of Chicago Press, 1999. 376 pp. 相似文献
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Janet M. Box-Steffensmeier Raphael C. Cunha Roumen A. Varbanov Yee Shwen Hoh Margaret L. Knisley Mary Alice Holmes 《PloS one》2015,10(11)
Background
Recruitment and retention of talent is central to the research performance of universities. Existing research shows that, while men are more likely than women to be promoted at the different stages of the academic career, no such difference is found when it comes to faculty retention rates. Current research on faculty retention, however, focuses on careers in science, technology, engineering, and mathematics (STEM). We extend this line of inquiry to the social sciences.Methods
We follow 2,218 tenure-track assistant professors hired since 1990 in seven social science disciplines at nineteen U.S. universities from time of hire to time of departure. We also track their time to promotion to associate and full professor. Using survival analysis, we examine gender differences in time to departure and time to promotion. Our methods account for censoring and unobserved heterogeneity, as well as effect heterogeneity across disciplines and cohorts.Results
We find no statistically significant differences between genders in faculty retention. However, we do find that men are more likely to be granted tenure than women. When it comes to promotion to full professor, the results are less conclusive, as the effect of gender is sensitive to model specification.Conclusions
The results corroborate previous findings about gender patterns in faculty retention and promotion. They suggest that advances have been made when it comes to gender equality in retention and promotion, but important differences still persist. 相似文献13.
Iturin A is a lipopeptide extracted from strains of Bacillus subtilis. Seven peptide residues form a cycle closed by a β-amino acid carrying a hydrophobic tail. This compound is an antifungal and induces the formation of conducting pores in black lipid membranes. Two-dimensional 1H-nmr was used for investigating its conformation in pyridine. A complete set of nuclear Overhauser effects (NOEs) was obtained from which interproton distances were deduced in a rather broad range of 2.2–4.2 Å. A special procedure was then used to optimize simultaneously experimental parameters and intramolecular energy calculated by semiempirical methods. A model of the conformation is proposed for the backbone for which there is an excellent coherence between NOEs, coupling constants, and intramolecular energy. The conformations of Asn, Gln, and Ser side chains appear to be much more flexible because of their interactions with the solvent. From this picture, iturin A seems to have a rather stiff ring surrounded by mobile side chains. Further studies of this lipopeptide and of other members of the family should enable us to approach some structure–activity relationships for this class of antibiotics. 相似文献
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Damselflies provide a classic example of female colour polymorphism. Usually, one female morph resembles the blue male colour
(andromorph) while one, or more, female morphs are seen as typically female (gynomorph). Damselfly species fall in two distinct
groups with respect to recent developments in mimicry theory: in some species females are perfect, they match male colouration
and black patterning, and in other species they are supposed to be imperfect mimics, only matching male colouration. However,
the underlying assumption of one female morph looking male-like is mostly based on human vision. Therefore we investigated
the black patterning and colour of the three female morphs in Coenagrion puella, an imperfect mimic, using image analysis. In C. puella the blue female morph is perceived as male-like. We found that the black patterning of such females cannot be distinguished
from the other female morphs, and is clearly different from males. Furthermore, the blue colour of andromorph females differs
from the blue colour of males. Intriguingly, however, the red content did not differ between blue males and females. 相似文献
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MARÍA ELENA GARCÍA 《American anthropologist》2006,108(3):569-570
Natives Making Nation: Gender, Indigeneity, and the State in the Andes. Andrew Canessa, ed. Tucson: University of Arizona Press, 2005. 201 pp. 相似文献
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Phosphorylation-induced torsion-angle strain in the active center of HPr, detected by NMR and restrained molecular dynamics refinement.
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N. A. Van Nuland J. A. Wiersma D. Van Der Spoel B. L. De Groot R. M. Scheek G. T. Robillard 《Protein science : a publication of the Protein Society》1996,5(3):442-446
The structure of the phosphorylated form of the histidine-containing phosphocarrier protein HPr from Escherichia coli has been solved by NMR and compared with that of unphosphorylated HPr. The structural changes that occur upon phosphorylation of His 15, monitored by changes in NOE patterns, 3JNHH alpha-coupling constants, and chemical shifts, are limited to the region around the phosphorylation site. The His15 backbone torsion angles become strained upon phosphorylation. The release of this strain during the phosphoryl-transfer to Enzyme II facilitates the transport of carbohydrates across the membrane. From an X-ray study of Streptococcus faecalis HPr (Jia Z, Vandonselaar M, Quail JW, Delbaere LTJ, 1993, Nature 361:94-97), it was proposed that the observed torsion-angle strain at residue 16 in unphosphorylated S. faecalis HPr has a role to play in the protein's phosphocarrier function. The model predicts that this strain is released upon phosphorylation. Our observations on E. coli HPr in solution, which shows strain only after phosphorylation, and the fact that all other HPrs studied thus far in their unphosphorylated forms show no strain either, led us to investigate the possibility that the crystal environment causes the strain in S. faecalis HPr. A 1-ns molecular dynamics simulation of S. faecalis HPr, under conditions that mimic the crystal environment, confirms the observations from the X-ray study, including the torsion-angle strain at residue 16. The strain disappeared, however, when S. faecalis HPr was simulated in a water environment, resulting in an active site configuration virtually the same as that observed in all other unphosphorylated HPrs. This indicates that the torsion-angle strain at Ala 16 in S. faecalis HPr is a result of crystal contacts or conditions and does not play a role in the phosphorylation-dephosphorylation cycle. 相似文献
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Martin Rössler 《American anthropologist》2000,102(1):200-201
Struggling with Development: The Politics of Hunger and Gender in the Philippines. Lynn M. Kwiatkowski. Boulder, CO: Westview Press. 1998. 350 pp. 相似文献